Nonconventional method for drying of Pseudomonas aeruginosa and its comparison with conventional methods - Umashankar, K.,; Chandralekha, A.; Dandavate, T.,; Tavanandi, H. A.; Raghavarao, K. S. M. S. (Drying Technology, 2018)
In this study, preparation of dried cultures of Pseudomonas aeruginosa using nonconventional drying method, namely, low-temperature low-humidity (LTLH) drying was investigated. The effect of carrier materials (whey protein, corn starch, and trehalose) was examined one at a time and also in combinations (to explore the synergistic effect). The results were compared with those obtained using spray drying and freeze drying in terms of cell survival and dry cell powder yield. The powder samples were analyzed also for morphology, flowability, particle size, and moisture content. In LTLH drying, good cell survival was observed along with high powder yield when compared with that in spray drying. Corn starch showed the highest cell survival (91%) and powder yield (94%, w/w) among the carrier materials employed besides resulting in good cell survival (65%) even after a storage period of 6 months.
Keywords: cell survival; Encapsulation; freeze drying; Low-temperature low-humidity (LTLH) drying; Pseudomonas aeruginosa; spray drying

Non-isothermal analysis of extrusion film casting using multi-mode Phan-Thien Tanner constitutive equation and comparison with experiments - Chougale, Sanket; Rokade, Dhammaraj; Bhattacharjee, Tanushree; Pol, Harshawardhan; Dhadwal, Renu (Rheologica Acta, 2018)
Extrusion film casting (EFC) is an industrially important process which produces thousands of tons of polymer films, sheets, and coating used for various industrial as well as household applications. In this paper, we focus on an instability which occurs during certain polymer processing operations operating under predominantly elongational flow, such as extrusion film casting and fiber spinning. This instability, called the draw resonance, occurs in the form of sustained periodic fluctuations in the film dimensions. It appears when the process goes beyond the critical line speed of the EFC process. In this work, a conventional linear stability analysis is carried out for nonisothermal EFC process to determine the onset of the draw resonance. The polymer rheology is modeled by the Phan-Thien Tanner (PTT) multi-mode constitutive equation. For the implementation, a conventional shooting method approach is used. Extrusion film casting experiments were also carried out using a conventional linear low-density polyethylene (LLDPE) by varying process parameters such as draw ratio and aspect ratio, to observe the effect on the stability of the process. Linear stability analysis results under non-isothermal conditions are compared and validated with existing results from literature and with our own experimental data. This work displays the effect of multiple relaxation modes as well as the temperature influence on the stability of EFC process. Finally, results also indicate that the temperature highly affects the stability of the EFC process and cannot be ignored from modeling of EFC process.
Keywords: Deborah number; Draw resonance; Film extrusion; Multi-mode; Nonisothermal; stability

Novel synthesis of immobilized bronsted- acidic ionic liquid: application in lignin depolymerization - Singh, Sandip K.; Dhepe, Paresh L. (Chemistryselect, 2018)
Designing of efficient catalyst for the valorization of lignin is a topic of long neglect due to intrinsic properties of lignin. We show designing of an efficient, stable and recyclable Immobilized-Bronsted acidic ionic liquid (I-BAIL), which was further used as a solid acid catalyst for the depolymerization of lignin. The synthesized I-BAIL catalyst with sulfonic acid (-SO3H) groups was found to be stable until 250 degrees C and has 42.2 wt.% loading of BAIL anchored on silica framework. The detailed characterization (elemental, Thermogravimetric analysis, Fourier transformation-infrared, Nuclear magnetic resonance) of catalyst disclosed formation of strong covalent bond between Si and carbon of BAIL, which in turn is responsible for achieving a stable catalyst. The catalyst could successfully depolymerize range of lignin substrates with high molecular weight (60000 Dalton) at 200(degrees)C in 1 h to achieve 90% yield of tetrahydrofuran soluble products with good mass balance. The formation of products and correlation of products with lignin was achieved with the help of Nuclear magnetic resonance, gel permeation chromatography, gas chromatography, gas chromatography-mass spectrometry, high performance liquid chromatography etc.

Nutritional quality and antioxidant activity of wheatgrass (Triticum aestivum) unwrap by proteome profiling and DPPH and FRAP assays - Parit, Santosh B.; Dawkar, Vishal V.; Tanpure, Rahul S.; Pai, Sandeep R.; Chougale, Ashok D. (Journal of Food Science, 2018)
Precious contribution of plants in the field of medicine is very well known. Wheat (Triticum aestivum) seeds and seedlings are an important source of food and feed due to the presence of various health-promoting compounds. Proteomic analysis of three seed developmental stages (0, 8, and 16 days after germination [DAG]) of wheat was carried out using liquid chromatography-mass spectrometry. A total of 297 proteins were identified and their functional annotation revealed that a majority of them were involved in preventing many diseases, oxidative stress, primary metabolism, storage, and energy related mechanisms. Particularly to mention, peroxidases, superoxide dismutases, and cytochromes are abundantly present in wheatgrass. In the ferric-reducing antioxidant power assay, antioxidant activity was increased by 1.55 times after 16 DAG as compared to 0 DAG, however it was decreased after 8 DAG. The antioxidant activity of the plant extracts by DPPH had an increasing trend after all the three time points. The percent radical scavenging activity of extract by DPPH was 15, 22, and 30 after 0, 8, and 16 DAG, respectively. Observations obtained revealed that antioxidant power of the plants is directly proportional to the age of seedlings. Data attained on wheatgrass showing that it can be a strong antioxidant agent due to its free radical scavenging activity and could be used in stress and nourishing human health. Practical ApplicationWheatgrass contains minerals, phytochemicals, active enzymes, and vitamins that can be easily absorbed. The consumption of wheatgrass juice can give better health benefits. Information about beneficial properties of wheat grass juice is clearly mentioned in this work.Proteins found in wheatgrass are known to be involved in preventing many diseases, oxidative stress, primary metabolism, storage, and energy-related mechanisms. Results of this work revealed that Triticum aestivum seedlings can act as an antioxidant agent due to their free radical scavenging activity and can be constructive to control or treat many health complications. From all these results we believed that wheatgrass can be used for the nourishment of humans.
Keywords: Antioxidant; LC-MSE; peroxidase; proteomics; Triticum aestivum; wheatgrass

One pot conversion of furfural to 2-methylfuran in the presence of PtCo bimetallic catalyst - Dohade, M.G.; Dhepe, P. L. (Clean Technologies and Environmental Policy, 2018)
Biomass-derived furfural (FAL) is the platform chemical for synthesis of various value-added chemicals and fuels. One of the FAL-derived chemicals, i.e., 2-methylfuran (2-MF), is the potential biofuel due to its attractive chemical and physical properties. Various methods are reported for conversion of FAL to 2-MF which are operated at high temperature and high H2 pressure. In present work, one pot catalytic method was developed in batch mode process for conversion of FAL to 2-MF. Reactions are carried out in the presence of PtCo/C bimetallic catalyst under 0.5–1 MPa H2 pressure. Monometallic and bimetallic catalysts with different Pt and Co loading were prepared by wet impregnation method, and catalysts were characterized by transmission electron microscopy, BET surface area, X-ray photoelectron spectroscopy, X-ray diffraction and inductive coupled plasma atomic emission spectroscopy techniques. 59% 2-MF yield was achieved at 180 °C and lower (0.5 MPa) H2 pressure.
Keywords: 2-Methylfuran; Bimetallic catalyst; Co-impregnation; furfural; Hydrodeoxygenation; Hydrogenation

One pot synthesis and biological evaluation of some new pyridine-3,5-dicarbonitrile derivatives - Joshi, Hitendra; Shah, Nirav; Sakar, Dhiman; Desai, N. C.; Jadeja, Krunalsinh A. (ChemistrySelect, 2018)
We have developed eco-friendly route for the synthesis of title compounds by using simple compounds like aromatic aldehydes, malononitrile, 4-bromothiophenol and NaHCO3. In continuation to this, a series of pyridine-3,5-dicarbonitriles were synthesized with excellent yields and assessed for their invitro antitubercular and antimicrobial activity. The results of the antimicrobial study showed potent antimicrobial activity as compared to the standard drugs (Chloramphenicol and Griseofulvin). It was noticed that the presence of electron donating groups significantly increases the antibacterial activity of the newly synthesized compounds. The title compounds further evaluated for antitubercular activity and from the promising results, they were found to possess significant biological activity against M. tuberculosis.
Keywords: 3; 4-Arylpyridine; 5-dicarbonitriles; Antimicrobial; Antitubercular; Catalyst

Organocatalytic asymmetric cascade reaction of gamma-substituted deconjugated butenolides with o-formyl-beta-nitrostyrene - Deepake, Siddharth K.; Lanjewar, Atul B.; Thatikonda, Thanusha; Gonnade, Rajesh G.; Das, Utpal (ChemistrySelect, 2018)
An efficient chemo-, diastereo- and enantio-selective cascade synthesis of functionalized indanols bearing four contiguous stereogenic centres has been developed via the reaction of beta,gamma-butenolides with o-formyl-beta-nitrostyrenes in the presence of bi-functional hydrogen-bonding catalyst. Indanol derivatives containing gamma,gamma-disubstituted butenolides were obtained in good yields and with moderate to high enantioselectivities/diastereoselectivities.
Keywords: butenolides; Cascade reaction; Enantioselectivity; Indanol; organocatalysis

Oxidative NHC catalysis for the generation of imidoyl azoliums: synthesis of benzoxazoles - Patra, Atanu; James, Anjima; Das, Tamal Kanti; Biju, Akkattu T. (Journal of Organic Chemistry, 2018)
N-Fleterocyclic carbene (NHC)-catalyzed intramolecular cyclization of aldimines generated from 2-amino phenols and aromatic aldehydes leading to the synthesis of 2-arylbenzoxazoles under mild conditions is presented. The reaction proceeds via the generation of the aza-Breslow intermediates from imines and NHC, which under oxidative conditions form the key imidoyl azoliums and a subsequent intramolecular cyclization furnishes the product. The reaction tolerates a broad range of functional groups, and the products are formed in generally good yields.

pH- and time-resolved in situ SAXS study of self-assembled twisted ribbons formed by elaidic acid sophorolipids - Dhasaiyan, Prabhu; Prevost, Sylvain; Baccile, Niki; Prasad, Bhagavatula L. V. (Langmuir, 2018)
Conditions that favor the helical structure formation in structurally similar sophorolipids (SLs), that is, elaidic acid SLs (having a trans double bond between the C9 and C10 positions of the alkyl chain) and stearic acid SLs (no double bond), are presented here. The helical self-assembled structures formed by elaidic acid SLs were independent of pH and also were mediated by a micellar intermediate. On the other hand, the stearic acid SLs formed helical structures under low pH condition only. Astonishingly, the formation routes were found to be different, albeit the molecular geometry of both SLs is similar. Even if a conclusive mechanistic understanding must await further work, our studies strongly point out that the noncovalent weak interactions in elaidic acid SLs are able to overcome the electrostatic repulsions of the sophorolipid carboxylate groups at basic pH and facilitating the formation of helical structures. On the other hand, the hydrophobic interactions in stearic acid SLs endow the helical structures with extra stability, making them less vulnerable to dissolution upon heating.

pH dependent sophorolipid assemblies and their influence on gelation of silk fibroin protein - Dubey, Parul; Kumar, Sugam; Ravindranathan, Sapna; Vasudevan, Sahana; Aswal, Vinod K.; Rajamohanan, Pattuparambil R.; Nisal, Anuya; Prabhune, Asmita (Materials Chemistry and Physics, 2018)
Sophorolipid (SL), a bio-derived surfactant is an excellent gelling agent for natural fibrous protein, silk fibroin (SF) leading to potential biomedical applications. Interaction of SF with SL has been shown to accelerate the formation of hydrogel with the rate being dependent on the form of SL used. Here, we examine the effect of pH on SL-SF interaction and gel formation by employing rheology, fluorescence spectroscopy, SANS and NMR. The results indicate that the size of SL assemblies decrease as pH increases from acidic to alkaline and significantly impacts the association of SL and SF. The association of SF and SL is mainly via hydrophobic interactions, with the SL molecules forming bead like structures along the SF chain. The increased charge on the acidic form of SL at higher pH results in greater repulsion between acidic SL molecules, which are bound to the hydrophobic sites of SF, leading to rapid chain unfolding and subsequent gelation. (C) 2017 Elsevier B.V. All rights reserved.
Keywords: Assemblies; Nuclear magnetic resonance spectroscopy; pH; Silk fibroin; Small angle neutron scattering; Sophorolipid

Pharmaceutical standardization and physicochemical characterization of traditional ayurvedic marine drug: incinerated conch shell (shankha bhasma) - Chavan, Sandeep; Tayade, Sonali; Gupta, Vidya; Deshmukh, Vineeta; Sardeshmukh, Sadanand (Marine Drugs, 2018)
Natural resources such as plants, animals and minerals have always been used by mankind to develop drugs and marine world is no exception. Marine by-products like conches, pearls, mother of pearl shells, corals and so forth have been used by traditional Ayurvedic practitioners for centuries. The unique methods of these preparations are scientifically designed to eliminate unwanted impurities and convert them into bioavailable form. In this study, Conch (Xanchus pyrum) was used as a marine resource of calcium carbonate and was converted pharmaceutically from its aragonite form to calcite. All the steps of preparations and changes in the properties therein were documented and validated. Further, traditional as well as modern analytical tools were used to study its physical and chemical characters to develop a monograph. The physical characterization included particle size, X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA) and Fourier Transform Infra-red (FTIR). Metal composition and heavy metal limits were determined using Inductively Coupled Plasma Optical Emission Spectrometry (ICPOES). This study revealed the rearrangement of aragonite crystals into calcite form by grinding, trituration with aloe vera juice and incineration under controlled conditions. Moreover, the finished product was found to be devoid of organic matrix that is nacre. This study creates a foundation for the development of a master formula for commonly used Shankha Bhasma in Ayurvedic medicines.

Phenazine-containing poly(phenylenevinylene): a new polymer with impressive field emission properties - Chhatre, Shraddha; Ichake, Amol; Harpale, Kashmira; Patil, Sumati; Deshpande, Aparna; More, Mahendra; Wadgaonkar, Prakash P. (Journal of Polymer Research, 2018)
Phenazine-containing poly(phenylenevinylene) (P(PHN-PV)) was synthesized using Wittig-Horner polycondensation of the appropriately designed monomers viz. 5,10-dioctyl-5,10-dihydrophenazine-2,7-dicarbaldehyde and tetraethyl ((2,5-bis((2-ethylhexyl) oxy)-1,4 phenylene) bis(methylene)) bis(phosphonate). The design embraces the specific motivation of incorporating the nitrogen-containing heterocycle viz. .phenazine in poly(phenylenevinylene) backbone. P(PHN-PV) exhibited reversible redox properties. In the field emission measurements performed on the film of P(F'HN-PV), the turn-on field was observed to be 1.93 V/mu m for the current density of 10 mu A/cm(2). The maximum current density of similar to 4.87 mA/cm(2) was achieved at the applied field of 3.84 V/mu m. The emission current showed impressive stability for 6 h at a constant current of 1 mu A (current density of about 20 mu A/cm(2)). These results emphasize the role of phenazine heterocycle with lone pair of electrons on nitrogen in lowering the oxidation onset and in turn reduction of the turn-on voltage.
Keywords: field emission; Phenazine; Poly(phenylenevinylene)

Polysulfide-triggered fluorescent indicator suitable for super-resolution microscopy and application in imaging - Hoskere, Anila A.; Sreedharan, Sreejesh; Ali, Firoj; Smythe, Carl G.; Thomas, Jim A.; Das, Amitava (Chemical Communications, 2018)
A new physiologically benign and cell membrane permeable BODIPY based molecular probe, MB-S-n, specifically senses intracellular hydrogen polysulfides (H2Sn, n > 1) localized in the endoplasmic reticulum. This reagent is suitable for mapping the intracellular distribution of H2Sn by wide-field as well as super-resolution Structured Illumination Microscopy (SIM).

Prediction of coal ash fusion temperatures using computational intelligence based models - Tambe, S.S.; Naniwadekar, M.; Tiwary, S.; Mukherjee, A.; Das, T. B. (International Journal of Coal Science and Technology, 2018)
In the coal-based combustion and gasification processes, the mineral matter contained in the coal (predominantly oxides), is left as an incombustible residue, termed ash. Commonly, ash deposits are formed on the heat absorbing surfaces of the exposed equipment of the combustion/gasification processes. These deposits lead to the occurrence of slagging or fouling and, consequently, reduced process efficiency. The ash fusion temperatures (AFTs) signify the temperature range over which the ash deposits are formed on the heat absorbing surfaces of the process equipment. Thus, for designing and operating the coal-based processes, it is important to have mathematical models predicting accurately the four types of AFTs namely initial deformation temperature, softening temperature, hemispherical temperature, and flow temperature. Several linear/nonlinear models with varying prediction accuracies and complexities are available for the AFT prediction. Their principal drawback is their applicability to the coals originating from a limited number of geographical regions. Accordingly, this study presents computational intelligence (CI) based nonlinear models to predict the four AFTs using the oxide composition of the coal ash as the model input. The CI methods used in the modeling are genetic programming (GP), artificial neural networks, and support vector regression. The notable features of this study are that the models with a better AFT prediction and generalization performance, a wider application potential, and reduced complexity, have been developed. Among the CI-based models, GP and MLP based models have yielded overall improved performance in predicting all four AFTs.

Preparation of metal oxide supported catalysts and their utilization for understanding the effect of a support on the catalytic activity - Seth, Jhumur; Dubey, Prashant; Chaudhari, Vijay R.; Prasad, Bhagavatula L. V. (New Journal of Chemistry, 2018)
A convenient way of anchoring transition metal nanoparticles (palladium, platinum, rhodium and ruthenium) onto metal oxide supports (magnesium oxide and zirconium oxide) by means of a modified sol-gel technique is demonstrated. Use of toluene dispersed, ligand protected pre-synthesized nanoparticles during sol-gel synthesis delivered size-controlled, spatially distributed, well-adhered transition metal nanoparticles (MNPs) on metal oxide supports. The catalytic activities of these supported nanoparticles were tested for the p-nitro phenol reduction reaction. It was observed that the reaction kinetics were crucially dependent on the catalyst support and MNP size. The influence of the magnesium oxide and zirconium oxide supports towards the catalytic performance of the anchored transition MNPs was probed using cyclic voltammetry and the differences in the same were attributed to the support-induced modification in the electronic properties of the MNPs. Our results indicated that magnesium oxide is a better support than zirconium oxide.

Proteomic study of endothelial dysfunction induced by Ages and its possible role in diabetic cardiovascular complications - Banarjee, Reema; Sharma, Akshay; Bai, Shakuntala; Deshmukh, Arati; Kulkarni, Mahesh J. (Journal of Proteomics, 2018)
Endothelial dysfunction is one of the primary steps in the development of diabetes associated cardiovascular diseases. Hyperglycemic condition in diabetes promotes accumulation of advanced glycation end products (AGEs) in the plasma, that interact with the receptor for AGEs (RAGE) present on the endothelial cells and negatively affect their function. Using Human umbilical vascular endothelial cells (HUVECs) in culture, the effect of glycated human serum albumin on global proteomic changes was studied by SWATH-MS, a label free quantitative proteomic approach. Out of the 1860 proteins identified, 161 showed higher abundance while 123 showed lesser abundance in cells treated with glycated HSA. Bioinformatic analysis revealed that the differentially regulated proteins were involved in various processes such as apoptosis, oxidative stress etc. that are associated with endothelial dysfunction. Furthermore, the iRegulon analysis and immunofuorescence studies indicated that several of the differentially regulated proteins were transcriptionally regulated by NF-kappa B, that is downstream to AGE-RAGE axis. Some of the important differentially regulated proteins include ICAM1, vWF, PAI-1 that affect important endothelial functions like cell adhesion and blood coagulation. qPCR analysis showed an increase in expression of the AGE receptor RAGE along with other genes involved in endothelial function. AGE treatment to HUVEC cells led to increased oxidative stress and apoptosis. This is the first proteomics study that provides insight into proteomic changes downstream to AGE-RAGE axis leading to endothelial dysfunction and predisposing to cardiovascular complications. Significance: Cardiovascular disease (CVD) is a major pathological outcome in diabetic patients and it is important to address ways that target its development before the onset. Elevated plasma AGEs in diabetes can affect endothelial function and can continue to show their effects even after blood glucose levels are back to normal. Since endothelial dysfunction acts as one of the initiating factors for the development of CVD, understanding how AGEs affect the endothelial cell proteome to cause dysfunction will provide insight into the mechanisms involved and aid designing new therapeutic approaches.

Pt - g-C3N4 - (Au/TiO2): electronically integrated nanocomposite for solar hydrogen generation - Devaraji, Perumal; Gopinath, Chinnakonda S. (International Journal of Hydrogen Energy, 2018)
A potential nanocomposite photocatalyst was designed by integrating Pt nanoclusters (co catalyst and electron sink) with graphitic carbon nitride (g-C3N4 (gcn)) (charge diffusion) and 0.5 wt % Au containing Au-TiO2 (AuT) (plasmonic on semiconductor) for solar water splitting (SWS). Variety of Pt-gcn-AuTiO2 compositions has been evaluated for SWS under one sun conditions. Complexity of the photocatalyst was increased systematically from Au-TiO2, gcn-TiO2 to Pt-gcn-Au-TiO2 to explore the influence of different combinations. Electronic integration of charge separation/diffusion component (gcn) with light absorbing sensitizer components (Au and gcn), and co-catalyst (Pt) seems to be the critical factor to improve hydrogen yield (HY) or overall efficiency. Although addition of gcn increase the HY of composites, there is no SWS activity observed on bare TiO2 or gcn. Au or Pt on gcn enhances the charge separation effectively and interface between Au and/or Pt with gcn works as the Schottky barrier. A monodispersion of Au over TiO2 and Pt nanoclusters over gcn/AuTiO2 composite lead to the maximum solar hydrogen yield (1.52 mmol/h g) with an apparent quantum yield (AQY) of 7.5%. Photoelectron and photoluminescence spectral studies confirm the electron transfer from Au to gcn, and Au and/or gcn to titania. A thorough physico-chemical investigation of various composites underscores the electronic integration aspects of the nanocomposite towards storage of electrons in the Pt co-catalyst and hence an effective charge separation and an increase in AQY. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Keywords: Electronic integration; Photocatalysis; Schottky barrier; Solar hydrogen; water splitting

Rational design of coumarin derivatives as antituberculosis agents - Mali, Hemlata M.; Sabale, Sandip S.; Degani, Mariam S.; Borkute, Rachana; Choudhari, Amit S.; Sarkar, Dhiman; Krishna, Vagolu Siva; Sriram, Dharmarajan (Future Medicinal Chemistry, 2018)
A series of coumarin derivatives was designed as potential antituberculosis agents. Results: The compounds were screened against active and dormant Mycobacterium tuberculosis (Mtb). Compounds 3k and 3n were found to have the most promising activity against replicating MtbH37Rv exhibiting minimum inhibitory concentration of 4.63 and 9.75 mu M respectively. The compounds were also effective against dormant MtbH37Rv exhibiting more potency than the standard drugs, isoniazid and rifampicin. The compounds were found to be non-cytotoxic against human cell lines. Conclusion: This study provides promising antituberculosis agents that are effective against replicating as well as dormant Mtb and can thus act as potential leads for further development.

Reaction engineering for continuous production of silver nanoparticles - Deshpande, Javdeep B.; Kulkarni, Amol A. (Chemical Engineering & Technology, 2018)
A scalable process for the production of silver nanoparticles that allows for complete conversion of the limiting reactant is analyzed in detail. The kinetics of silver nanoparticle synthesis using citrate reduction are investigated and used for development of a reaction engineering model to facilitate the reactor design. The effect of temperature, pH, concentration and mixing (axial dispersion) on the rates of nucleation and growth are analyzed quantitatively. An approach that considers reaction kinetics coupled with quality of dispersion is developed for reactor design as well as selection of reactor configurations for the synthesis of specific particle sizes. The developed approach has been applied for continuous production of 10-L suspension silver nanoparticles with very narrow particle size distribution.
Keywords: kinetics; particle size distribution; rate constant; Reactor design; Silver nanoparticle production

Repeated photoporation with graphene quantum dots enables homogeneous labeling of live cells with extrinsic markers for fluorescence microscopy - Liu, Jing; Xiong, Ranhua; Brans, Toon; Lippens, Saskia; Parthoens, Eef; Zanacchi, Francesca Cella; Magrassi, Raffaella; Singh, Santosh K.; Kurungot, Sreekumar; Szunerits, Sabine; Bove, Hannelore; Ameloot, Marcel; et al. (Light-Science & Applications, 2018)
In the replacement of genetic probes, there is increasing interest in labeling living cells with high-quality extrinsic labels, which avoid over-expression artifacts and are available in a wide spectral range. This calls for a broadly applicable technology that can deliver such labels unambiguously to the cytosol of living cells. Here, we demonstrate that nanoparticle-sensitized photoporation can be used to this end as an emerging intracellular delivery technique. We replace the traditionally used gold nanoparticles with graphene nanoparticles as photothermal sensitizers to permeabilize the cell membrane upon laser irradiation. We demonstrate that the enhanced thermal stability of graphene quantum dots allows the formation of multiple vapor nanobubbles upon irradiation with short laser pulses, allowing the delivery of a variety of extrinsic cell labels efficiently and homogeneously into live cells. We demonstrate high-quality time-lapse imaging with confocal, total internal reflection fluorescence (TIRF), and Airyscan super-resolution microscopy. As the entire procedure is readily compatible with fluorescence (super resolution) microscopy, photoporation with graphene quantum dots has the potential to become the long-awaited generic platform for controlled intracellular delivery of fluorescent labels for live-cell imaging.

Sensitizing with short conjugated molecules: multimodal anchoring on ZnO nanoparticles for enhanced electron transfer characteristics, stability and H-2 evolution - George, Leena; Sappati, Subrahmanyam; Ghosh, Prasenjit; Devi, R. Nandini (Catalysis Today, 2018)
Sensitizing semiconductors with organic dyes is usually employed to improve efficiency of semiconductors towards visible light absorption and charge transport. However, till date most of the dyes are either noble metal based with complex and expensive synthesis procedure or have a very narrow absorption band. Further the photostability of the dyes is another important issue. In this work we have studied, using a combination of photophysical and computational methods, ZnO nanoparticles sensitized with transition metal free, cheap and easy to synthesize azoquinoline dye that has been designed to have multiple chelating sites, viz., carboxylic group and hydroxyl imine group as a photocatalyst for water splitting activity. We find that the presence of multiple chelating sites facilitates dual mode of anchoring on ZnO nanoparticles, which leads to enhanced photostability and H-2 generation of the composite. This is attributed to the incorporation of resonance features in the dye that increases electron transfer between ZnO and dye in contrast to the charge accumulation and photo degradation observed in non-conjugated and single site anchoring counterparts. Electron transfer from ZnO to dye under UV light and reverse in visible light could be identified experimentally. Such simple designing aspects can aid in identifying better catalysts for photocatalytic water splitting.

Silk cocoon as counter - electrode substrate in dye - sensitized solar cells - Sudhakar, Vediappan; Das, Chayanika; Krishnamoorthy, Kothandam (ChemistrySelect, 2018)
Electrodes are vital components of energy conversion devices such as dye sensitized solar cells (DSSCs). The widely used electrodes consist of fluorine doped tin oxide (FTO) and platinum. We were interested in identifying a substrate that is available from natural resources and exhibit performance comparable to that of Pt coated FTO (Pt-FTO). Silk fibers are naturally available and they are mechanically stable. The woven silk fibers are known as silk cocoons (SCs) that structurally resemble widely used carbon paper electrodes. To impart conductivity to the insulating SCs, metal film was coated by an electroless metal plating procedure using polyphenols from green tea. The metal coated SCs were conformaly coated with a conjugated polymer and these electrodes were used as flexible electrodes in DSSCs. The flexible electrode based DSSCs exhibited a power conversion efficiency of 7.2% which is comparable to that of the DSSCs with rigid Pt-FTO based devices (7.4%).
Keywords: counter electrode; PEDOT-G-SCs; Recombination; Silk cocoons (SCs)

Silk fibroin micro-particle scaffolds with superior compression modulus and slow bioresorption for effective bone regeneration - Nisal, Anuya; Sayyad, Raeesa; Dhavale, Prachi; Khude, Bhakti; Deshpande, Rucha; Mapare, Vidhyashri; Shukla, Swati; Venugopalan, Premnath (Scientific Reports, 2018)
Silk fibroin (SF), a natural polymer produced by Bombyx mori silkworms, has been extensively explored to prepare porous scaffolds for tissue engineering applications. Here, we demonstrate, a scaffold made of SF, which exhibits compression modulus comparable to natural cancellous bone while retaining the appropriate porosities and interconnected pore architecture. The scaffolds also exhibit high resistance to in-vitro proteolytic degradation due to the dominant beta sheet conformation of the SF protein. Additionally, the scaffolds are prepared using a simple method of microparticle aggregation. We also demonstrate, for the first time, a method to prepare SF micro-particles using a Hexafluoroisopropanol-Methanol solvent-coagulant combination. SF microparticles obtained using this method are monodisperse, spherical, non-porous and extremely crystalline. These micro-particles have been further aggregated together to form a 3D scaffold. The aggregation is achieved by random packing of these microparticles and fusing them together using a dilute SF solution. Preliminary in-vitro cell culture and in-vivo implantation studies demonstrate that the scaffolds are biocompatible and they exhibit the appropriate early markers, making them promising candidates for bone regeneration.

Single pot selective hydrogenation of furfural to 2-methylfuran over carbon supported iridium catalysts - Date, Nandan S.; Hengne, Amol M.; Huang, K-W.; Chikate, Rajeev C.; Rode, Chandrashekhar V. (Green Chemistry, 2018)
Various iridium supported carbon catalysts were prepared and screened for the direct hydrogenation of furfural (FFR) to 2-methyl furan (2-MF). Amongst these, 5% Ir/C showed excellent results with complete FFR conversion and highest selectivity of 95% to 2-MF at a very low H-2 pressure of 100 psig. Metallic (Ir degrees) and oxide (IrO2) phases of Ir catalyzed the first step hydrogenation involving FFR to FAL and subsequent hydrogenation to 2-MF, respectively. This was confirmed by XPS analysis and some control experiments. At a low temperature of 140 degrees C, almost equal selectivities of FAL (42%) and 2-MF (43%) were observed, while the higher temperature (220 degrees C) favored selective hydrodeoxygenation. At optimized temperature, 2-MF was formed selectively while higher pressure and higher catalyst loading favored ring hydrogenation of furfural rather than side chain hydrogenation. With the combination of several control experimental results and detailed catalyst characterization, a plausible reaction pathway has been proposed for the selective formation of 2-MF. The selectivity to various other products in FFR hydrogenation can be manipulated by tailoring the reaction conditions over the same catalyst.

Single-pot reductive rearrangement of furfural to cyclopentanone over silica-supported Pd catalysts - Date, Nandan S.; Kondawar, Sharda E.; Chikate, Rajeev C.; Rode, Chandrashekhar V. (ACS Omega, 2018)
Direct one-pot hydrogenation of furfural (FFR) to cyclopentanone (CPO) was investigated over different silica-supported Pd catalysts. Among these, 4% Pd on fumed silica (4%Pd/f-SiO2) showed remarkable results, achieving almost 98% furfural (FFR) conversion with similar to 89% selectivity and 87% yield to cyclopentanone at 165 degrees C and 500 psig H-2 pressure. More interestingly, the fumed-silica-supported catalyst tuned the selectivity toward the rearrangement product, i.e, cyclopentanone, whereas all of the other supports were found to give ring hydrogenation as well as side chain hydrogenation products due to their parent Bronsted acidity and specific support properties. X-ray diffraction data revealed the presence of different phases of the face-centered cubic lattice of metallic Pd along with lowest crystallite size of 15.6 nm in the case of the silica-supported Pd catalyst. However, Pd particle size was found to be in the range of 5-13 nm with even dispersion over the silica support, confirmed by high-resolution transmission electron microscopy analysis. While studying the effect of reaction parameters, it was observed that lower temperature gave low furfural conversion of 58% with only 51% CPO selectivity.. Similarly, higher H-2 pressure lowered CPO selectivity with subsequent increase in 2-methyl furan and ring hydrogenation product 2-methyl furan and 2-methyl tetrahydrofuran. Thus, as per the requirement, the product selectivity can be tuned by varying the type of support and/or the reaction parameters suitably. With the help of several control experiments and the characterization data, a plausible reaction pathway was proposed for the selective formation of cyclopentanone.

Specific stereoisomeric conformations determine the drug potency of cladosporin scaffold against malarial parasite - Das, Pronay; Babbar, Palak; Malhotra, Nipun; Sharma, Manmohan; Jachak, Goraknath R.; Gonnade, Rajesh G.; Shanmugam, Dhanasekaran; Harlos, Karl; Yogavel, Manickam; Sharma, Amit; Reddy, D. Srinivasa (Journal of Medicinal Chemistry, 2018)
The dependence of drug potency on diastereomeric configurations is a key facet. Using a novel general divergent synthetic route for a three-chiral center antimalarial natural product cladosporin, we built its complete library of stereoisomers (cladologs) and assessed their inhibitory potential using parasite-, enzyme-, and structure-based assays. We show that potency is manifest via tetrahyropyran ring conformations that are housed in the ribose binding pocket of parasite lysyl tRNA synthetase (KRS). Strikingly, drug potency between top and worst enantiomers varied 500-fold, and structures of KRS-cladolog complexes reveal that alterations at C3 and C10 are detrimental to drug potency whereas changes at C3 are sensed by rotameric flipping of glutamate 332. Given that scores of antimalarial and anti-infective drugs contain chiral centers, this work provides a new foundation for focusing on inhibitor stereochemistry as a facet of antimicrobial drug development.

Spreading dynamics of superposed liquid drops on a spinning disk - Sahoo, Subhadarshinee; Orpe, Ashish V.; Doshi, Pankaj (Physics of Fluids, 2018)
We have experimentally studied simultaneous spreading of superposed drops of two Newtonian liquids on top of a horizontal spinning disk using the flow visualization technique. An inner drop of high surface tension liquid is placed centrally on the disk followed by a drop of outer liquid (lower surface tension) placed exactly above that. The disk is then rotated at a desired speed for a range of volume ratios of two liquids. Such an arrangement of two superposed liquid drops does not affect the spreading behavior of the outer liquid but influences that of the inner liquid significantly. The drop spreads to a larger extent and breaks into more fingers (Nf) as compared to the case where the same liquid is spreading in the absence of outer liquid. The experimentally observed number of fingers is compared with the prediction using available theory for single liquid. It is found that the theory over-predicts the value of Nf for the inner liquid while it is covered by an outer liquid. We provide a theoretical justification for this observation using linear stability analysis. Our analysis demonstrates that for small but finite surface tension ratio of the two liquids, the presence of the outer interface reduces the value of the most unstable wave number which is equivalent to the decrease in the number of fingers observed experimentally. Finally, sustained rotation of the disk leads to the formation of droplets at the tip of the fingers traveling outwards. Published by AIP Publishing.

Steering the ester and gamma-valerolactone selectivities in levulinic acid hydrogenation - Kasar, Gayatri B.; Date, Nandan S.; Bhosale, P. N.; Rode, Chandrashekhar V. (Energy Fuels, 2018)
Both alkyl esters and γ-valerolactone (GVL) derived from levulinic acid (LA) have applications as renewable transportation fuel/fuel additives. Non-noble metal cobalt supported on La2O3 catalyst was developed for efficient cascade LA hydrogenation to GVL via esterification. LA hydrogenation in methanol alone yielded methyl levulinate (MeLA) as a major product along with 43% of GVL. Interestingly, hydrogenation in water gave almost complete selectivity to GVL; nevertheless, it was associated with significant metal leaching. Suppression of metal leaching and enhancement in selectivity to GVL could be achieved by a methanol/water (95:5) solvent system. XRD analysis of La2O3-supported catalysts evidenced the characteristic peaks of a mixture of La2O3 and La(OH)3 phases. Basicity, as well as acidity, of the catalyst as determined by CO2 and NH3 TPD was due to these La2O3, Co–La, and La(OH)3 phases which played an important role in directing the product selectivity in levulinic acid hydrogenation. At the low temperature of 160 °C, almost equal selectivities of MeLA (47%) and GVL (43%) were observed, while higher temperature (200 °C) favored further hydrogenation of MeLA to GVL (75%). Similarly, with an increase in reaction time to 9 h, the GVL selectivity achieved was as high as 80%. The selectivity to MeLA and GVL in LA hydrogenation over Co/La2O3 catalyst can be altered by suitably adjusting the reaction conditions.

Streptomyces sp metabolite(s) promotes Bax mediated intrinsic apoptosis and autophagy involving inhibition of mTOR pathway in cervical cancer cell lines - Dan, Vipin Mohan; Muralikrishnan, Balaji; Sanawar, Rahul; Vinodh, J. S.; Burkul, Bhushan Bapusaheb; Srinivas, Kalanghad Puthankalam; Lekshmi, Asha; Pradeep, N. S.; Dastager, Syed G.; Santhakumari, B.; Santhoshkumar, Thankayyan R.; Kumar, R. Ajay; et al. (Scientific Reports, 2018)
In cervical cancer, the association between HPV infection and dysregulation of phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway (PI3K/AKT/mTOR pathway) places mTOR as an attractive therapeutic target. The failure of current treatment modalities in advanced stages of this cancer and drawbacks of already available mTOR inhibitors demand for novel drug candidates. In the present study we identified the presence of a mTOR inhibitor in an active fraction of the ethyl acetate extract of Streptomyces sp OA293. The metabolites(s) in the active fraction completely inhibited mTORC1 and thereby suppressed activation of both of its downstream targets, 4E-BP1 and P70S6k, in cervical cancer cells. In addition, it also stalled Akt activation via inhibition of mTORC2. The mechanism of mTOR inhibition detailed in our study overcomes significant drawbacks of well known mTOR inhibitors such as rapamycin and rapalogs. The active fraction induced autophagy and Bax mediated apoptosis suggesting that mTOR inhibition resulted in programmed cell death of cancer cells. The molecular weight determination of the components in active fraction confirmed the absence of any previously known natural mTOR inhibitor. This is the first report of complete mTOR complex inhibition by a product derived from microbial source.

Structural and functional analysis of UGT92G6 suggests an evolutionary link between mono- and disaccharide glycoside-forming transferases - Huang, Fong-Chin; Giri, Ashok; Daniilidis, Melina; Sun, Guangxin; Härtl, Katja; Hoffmann, Thomas; Schwab, Wilfried (Plant and Cell Physiology, 2018)
Glycosylation mediated by UDP-dependent glycosyltransferase (UGT) is one of the most common reactions for the biosynthesis of small molecule glycosides. As glycosides have various biological roles, we characterized UGT genes from grapevine (Vitis vinifera). In silico analysis of VvUGT genes that were highly expressed in leaves identified UGT92G6 which showed sequence similarity to both monosaccharide and disaccharide glucoside-forming transferases. The recombinant UGT92G6 glucosylated phenolics, among them caffeic acid, carvacrol, eugenol and raspberry ketone, and also accepted geranyl glucoside and citronellyl glucoside. Thus, UGT92G6 formed mono- and diglucosides in vitro from distinct compounds. The enzyme specificity constant Vmax/Km ratios indicated that UGT92G6 exhibited the highest specificity towards caffeic acid, producing almost equal amounts of the 3- and 4-O-glucoside. Transient overexpression of UGT92G6 in Nicotiana benthamiana leaves confirmed the production of caffeoyl glucoside; however, the level of geranyl diglucoside was not elevated upon overexpression of UGT92G6, even after co-expression of genes encoding geraniol synthase and geraniol UGT to provide sufficient precursor. Comparative sequence and 3-D structure analysis identified a sequence motif characteristic for monoglucoside-forming UGTs in UGT92G6, suggesting an evolutionary link between mono- and disaccharide glycoside UGTs. Thus, UGT92G6 functions as a mono- and diglucosyltransferase in vitro, but acts as a caffeoyl glucoside UGT in N. benthamiana.

Structural and magnetic properties of La2Ni1-xCoxMnO6 compounds - Pramanik, Debabrata; Mukherjee, S.; Dan, Shovan; Nandy, A.; Pradhan, S. K.; Dasgupta, Papri; Poddar, Asok; Mukherjee, Manabendra; Manjunath, B.; Joy, P. A. (Materials Research Bulletin, 2018)
Single phase monoclinic La2Ni1-xMnO6 (x = 0.2, 0.4, 0.8) compounds, henceforth, referred as LNCxMO (x = 0.2, 0.4, 0.8) have been prepared by Sol-gel technique. The structural study and redox titration suggest that the samples are both La and O deficient. The generated atomic models using Rietveld refined structural parameters show octahedral distortion In the double perovskite structure. X-ray photoelectron spectroscopy (XPS) study has been used to determine the predominant valence states of Ni, Mn and Co ions. LNCxMO (x = 0.2, 0.4) are found to be Heisenberg ferromagnets whereas LNC0.8MO is a phase segregated system. In LNC0.4MO and LNO0.8MO, at temperatures above T-c, chi(-1)(T) curve shows the characteristics of Griffiths phase. The study of ac susceptibility and Isothermal remanent magnetization (IRM) discard the possibility of any glassy state at low temperatures. The antiphase boundaries (APBs), antisite disorders (ASDs) and oxygen vacancies play important roles in this system.

Structural characterization and magnetic properties of undoped and copper-doped cobalt ferrite nanoparticles prepared by the octanoate coprecipitation route at very low dopant concentrations - Kamta Tedjieukeng, H.M.; Tsobnang, P.K.; Fomekong, R.L.; Etape, E.P.; Joy, P.A.; Delcorte, A.; Lambi, J.N. (RSC Advances, 2018)
Nanoparticles of undoped and copper-doped cobalt ferrite Co1−xCuxFe2O4 at very low dopant concentrations (x = 0; 0.02; 0.04; 0.06; 0.08) were successfully synthesized by pyrolysis of the corresponding hetero metal octanoate precursors obtained via coprecipitation using the octanoate ligand as precipitating agent. The precursors were then characterized by FTIR, ICP-AES and TG-DTA analyses and the results reveal the formation of a copper-cobalt-iron hydroxooctanoate represented by the formula [Co1−xCuxFe2(C8H15O2)6(OH)2·2H2O]. The decomposition products obtained upon pyrolysis in air at 400 °C for 3 h were characterized by FTIR, XRD, SEM, TEM, XPS and VSM analyses. FTIR and XRD analyses showed the formation of a single phase mixed spinel ferrite while TEM analysis showed that the particles have a spherical shape with a mean size of 20 nm and form spherical agglomerates with sizes reaching 500 nm in some cases as the SEM images show. The chemical states of the metallic species in the samples were revealed by XPS to be Cu2+, Co2+ and Fe3+. These results combined with XRD confirmed the mixed spinel structure, Co1−xCuxFe2O4 in which Cu2+ ions substitute Co2+ ions in tetrahedral sites for x lower than 0.06 and in octahedral sites for x between 0.06 and 0.08. Magnetic parameters such as saturation magnetization (Ms), coercivity (Hc), remanent magnetization (Mr), magnetocrystalline anisotropy constant (K) and reduced magnetization (Mr/Ms), obtained from magnetic hysteresis loops measured at room temperature, are in agreement with this mixed spinel structure and also indicate that these materials are ferromagnetic and could be good candidates for applications in biomedicine and in microwave devices.

Study the effect of impact angle on slurry erosion wear of four different ductile materials - Nandre, Bhushan D.; Desale, Girish R. (Materials Today: Proceedings, 2018)
The test rig fabricated for the present work has an ability to study the effect of orientation angle of erosion wear. The particles of Indian Standard sand (Quartz) selected as erodent for the present investigation because it is the most widely occurs in natural slurries. Experimental investigations on erosion behavior of ductile materials AISI SS304, AA 6063, Copper and Brass have been carried out using solid-water mixtures of the above erodent. The erosion wear due to solid-liquid mixture of IS Sand and tap water at different impact angles shows typical ductile erosion behavior for the selected materials. The maximum erosion is observed at 22.5° angle for AISI SS 304, 45o for AA 6063, 22.5o for Copper and 30o for Brass. The minimum erosion is observed at 90o orientation angle for all the materials. The eroded specimens were examined under the Scanning Electron Microscope (SEM) at minimum and maximum wear orientation angles. The SEM micrographs of eroded specimens depict the mechanism of material removal.
Keywords: AA 6063; AISI SS304; brass; Copper; Quart; SEM; Slurry erosion

Substituent‐induced deformed ni–porphyrin as an electrocatalyst for the electrochemical conversion of water into dioxygen - Krishna, J. V. S.; Krishna, Narra Vamsi; Singh, Santosh K.; Shaw, Pankaj K.; Dhavale, Vishal M.; Vardhaman, Anil Kumar; Giribabu, Lingamallu (European Journal of Inorganic Chemistry, 2018)
The electrochemical water oxidation ability of complexes 5,15‐diphenylporphinatonickel(II) (A) and 5,15‐bis(3,5‐di‐tert‐butylphenyl)porphinatonickel(II) (B) in the oxygen evolution reaction (OER) have been investigated in an alkaline medium. Complex B was found to be kinetically and thermodynamically more active than complex A. The overpotential and Tafel slope of complex B are lower than those of complex A by 30 mV and around 45 mV/decade, respectively, which supports the higher activity of B. Moreover, stability tests endorse the sustainability of both samples under alkaline conditions. It has been found that the 3,5‐di‐tert‐butylphenyl substituent in B plays a decisive role in achieving a better OER onset potential and current than that obtained with A, which is a result of the modulation of the structural parameters of B. Furthermore, the measured OER activities of A and B have been correlated with their molecular arrangement as well as differences in their bonding characteristics and dipole moments. For further insight, the obtained results have been confirmed by a theoretical study.

Sucrose capped gold nanoparticles as a plasmonic chemical sensor based on non-covalent interactions: application for selective detection of vitamins B-1 and B-6 in brown and white rice food samples - Shrivas, Kamlesh; Nirmalkar, Nidhi; Thakur, Santosh Singh; Deb, Manas Kanti; Shinde, Sandip S.; Shankar, Ravi (Food Chemistry, 2018)
We report simple and selective method for detection of vitamins B-1 and B-6 in brown and white rice samples using localized surface plasmon resonance (LSPR) of sucrose capped gold nanoparticles (AuNPs) as a chemical sensor colorimetrically. Here, detection is based on the color change of AuNPs from pink to blue followed by a red shift of LSPR absorption band in UV-vis region with the addition of vitamins B-1 and B-6 into the NPs solution. A good linear range was observed in the range of 25-1000 ngmL(-1) with detection limit of 8 ngmL(-1) for B-1 and 50-1000 ngmL(-1) with detection limit of 15 ngmL(-1) for vitamins B-6. The employment of AuNPs for detection of B-1 and B-6 vitamins in rice food samples showed remarkable abilities in terms of the simplicity, low cost, stability, reproducibility and sensitivity.

Synthesis and biological evaluation of novel triazole-biscoumarin conjugates as potential antitubercular and anti-oxidant agents - Danne, Ashruba B. (Research on Chemical Intermediates, 2018)
The synthesis of a new series of triazole-biscoumarin conjugates by using a molecular hybridization approach is described. The newly synthesized compounds 6a–k were evaluated for their in vitro antitubercular activity against active and dormant Mtb H37Ra and anti-oxidant activity against DPPH radical scavenging. Molecular docking simulations for the antitubercular activity showed that the conjugates 6a–k bind in the pocket of the DprE1 enzyme. Most of the conjugates displayed good antitubercular activity against both the active and dormant Mtb H37Ra strain. The compound 6h displayed very good antitubercular activity against dormant Mtb H37Ra with an IC50 value of 1.44 μg/mL. Most of the synthesized conjugates exhibit excellent anti-oxidant activity with an IC50 of less than the standard BHT. Compound 6b is the most active among all the conjugates with an IC50 value of 08.17 ± 0.11 μg/mL. The molecular docking study shows good agreement between the observed antitubercular activity and the binding affinity.
Keywords: 1; 2; 3-triazoles; Anti-oxidant activity; Antitubercular activity; Biscoumarins; Molecular docking

Synthesis, biological evaluation, and molecular docking study of pyridine clubbed 1,3,4-oxadiazoles as potential antituberculars - Desai, N. C. (Synthetic Communications, 2018)
A series of pyridine clubbed 1,3,4-oxadiazole derivatives were efficiently synthesized, characterized by standard spectral techniques and evaluated for their in vitro antitubercular activity against Mycobacterium tuberculosis (MTB) H37Ra and Mycobacterium bovis BCG in active and dormant state using an established methods. Compounds 5a, 5m, and 5t were identified as the most active compounds against MTB. Molecular docking was performed against MTB enoyl-ACP (CoA) reductase (FabI/ENR/InhA) enzyme to predict the binding modes and affinity. The theoretical predictions from molecular docking could establish a link between the observed biological activity and the binding affinity shedding light into specific bonded and non-bonded interactions influencing the activity. The active compounds were studied for cytotoxicity against three cell lines and were found to be non-cytotoxic. Specificity of these compounds was checked by screening them for their antibacterial activity against four bacterial strains.
Keywords: antibacterial activity; antituberculosis activity; cytotoxicity activity

Synthesis of novel alpha-aminophosphonate derivatives, biological evaluation as potent antiproliferative agents and molecular docking - Deshmukh, Satish U. (ChemistrySelect, 2018)
A series of novel fluorine containing α‐aminophosphonate derivatives (4 a–4 q) were synthesized in excellent yield and high purity. All these novel Fluorinated α‐aminophosphonate compounds were screened for antiproliferative and apoptosis activity on human non small cell lung carcinoma cells (A549) and human skin melanoma cells (SK‐MEL‐2). Compounds 4 a, 4 b, 4 c, 4 f, 4 i, 4 j and 4 m were found to be more active antiproliferative agent against A549 and SK‐MEL‐2 cells with IC50 value 0.22 to 1.25 μM. Molecular docking study related to binding affinity and binding mode analysis showed that synthesized compounds had potential to inhibit human Topoisomerase IIa enzyme system. Flow cytometric study showed some of these derivatives also induced cell apoptosis and arrest cell cycle at G1 and at G2/M phase. Overall, this study provides future perspective of lead candidate for the future anticancer drug discovery initiatives.

Systematic synthesis of a 6-component organic-salt alloy of naftopidil, and pentanary, quaternary and ternary multicomponent crystals - Dandela, Rambabu; Tothadi, Srinu; Marelli, Udaya Kiran; Nangia, Ashwini (IUCrJ, 2018)
The single-crystal X-ray structure of a 6-component organic-salt alloy (hexanary) of naftopidil (1) (an active pharmaceutical ingredient) with benzoic acid (2) and four different hydroxy-substituted benzoic acids, i.e. salicylic acid (3), 2,3-dihydroxybenzoic acid (4), 2,4-dihydroxybenzoic acid (5) and 2,6-dihydroxybenzoic acid (6), is reported. The hexanary assembly originates from the observation that the binary salts of naftopidil with the above acids are isostructural. In addition to the 6-component solid, we also describe five 5-component, ten 4-component, and ten 3-component organic-salt alloys of naftopidil (1) with carboxylic acids (2)-(6). These alloys were obtained from different combinations of the acids with the drug. The synthetic design of the multicomponent organic alloys is based on the rationale of geometrical factors (shape and size) and chemical interactions (hydrogen bonds). The common supramolecular synthon in all these crystal structures was the cyclic N+ - H center dot center dot center dot O- and O-H center dot center dot center dot O hydrogen-bonded motif of R-2(2) (9) graph set between the 2-hydroxyammonium group of naftopidil and the carboxylate anion. This ionic synthon is strong and robust, directing the isostructural assembly of naftopidil with up to five different carboxylic acids in the crystal structure together with the lower-level multicomponent adducts. Solution crystallization by slow evaporation provided the multicomponent organic salts and alloys which were characterized by a combination of single-crystal X-ray diffraction, powder X-ray diffraction, NMR and differential scanning calorimetry techniques.

Thermal conductivity studies on magnetite nanofluids coated with short-chain and long-chain fatty acid surfactants - Lenin, R.; Dadwal, A.; Joy, P. A. (Bulletin of Materials Science, 2018)
The effect of the length of surfactant molecules on the surface of the nanoparticles on the thermal conductivity of nanofluids is studied. Magnetite (Fe3O4) nanoparticles of comparable sizes are stabilized with short-chain capric acid (C9H19COOH) and long-chain stearic acid (C17H35COOH) molecules. Thermal conductivity of the two surfactant-coated magnetite nanoparticles dispersed in toluene is measured as a function of the concentration of the particles in the fluids and in the presence of a magnetic field. Studies showed that the critical concentration for thermal conductivity enhancement is lower for stearic-acid-coated fluid as compared with the capric-acid-coated fluid. Comparable enhancement in the thermal conductivity is observed at higher concentrations of the particles. Relatively larger enhancement in the thermal conductivity is observed for the capric-acid-coated fluid in a magnetic field. The difference in the enhancement in the thermal conductivity, depending on the chain length of the surfactant, is explained in terms of the inter-particle magnetic interactions and formation of clusters.

Ti-doped Pd-Au catalysts for one-pot hydrogenation and ring opening of furfural - Date, Nandan Shreehari; La Parola, Valeria; Rode, Chandrashekhar Vasant; Testa, Maria Luisa (Catalysts, 2018)
Pd-Au bimetallic catalysts with different Pd/Au atomic ratios, supported on ordered structured silica (Hexagonal mesoporous silica-HMS, or Santa Barbara Amorphous-15-SBA-15) were evaluated for one-pot hydrogenation of furfural to 1,2-pentanediol. The surface and structural properties of the catalysts were deeply investigated by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), N-2 adsorption isotherms (BET), Infrared spectroscopy (IR), and acid capacity measurements. XPS studies revealed that Ti doped supports had higher dispersion of the active phase, particularly in the case of Pd-Au materials in which Ti played an important role in stabilizing the metallic species. Among the various process conditions studied, such as temperature (160 degrees C), catalyst amount (10% w/w), and reaction time (5 h), H-2 pressure (500 psi) was found to improve the 1,2-pentanediol selectivity. The SBA silica bimetallic Ti-doped system showed the best performance in terms of stability and reusability, after multiple cycles. Under specific reaction conditions, the synergism between Pd-Au alloy and Ti doping of the support allowed the ring opening pathway towards the formation of 1,2-pentanediol in furfural hydrogenation.
Keywords: Bimetallic catalyst; furfural; Hydrogenation; ring-opening

Total synthesis of an anticancer natural product (+/-)-peharmaline A and its analogues - Kulkarni, Akshay S.; Shingare, Rahul D.; Dandela, Rambabu; Reddy, D. Srinivasa (European Journal of Organic Chemistry, 2018)
First total synthesis of a rare beta-carboline-vasicinone hybrid alkaloid (+/-)-peharmaline A has been accomplished in just 3 steps starting from known compounds. Stereoselective Pictet-Spengler reaction to nitrogenated tertiary carbon center and one-pot construction of the tricyclic skeleton of vasicinone are the highlights of present synthesis. We have also synthesized structurally close analogues of the natural product by following the developed route.

Total synthesis of notoryne - Senapati, Sibadatta; Das, Shyamsundar; Ramana, Chepuri V. (Journal of Organic Chemistry, 2018)
The structure of notoryne comprises a halogenated 2,2'-bifuranyl moiety along with a terminal cis-enyne unit. In this work, we document the first total synthesis of notoryne, confirming its assigned relative and absolute configurations. The devised route comprises a glucose diacetonide-derived chiral pool intermediate as the starting point and 5-endo bromo-etherification for making the key bis-furan unit, anomeric C-allylation, as well as a relay cross-metathesis to install the cis-enyne unit.

Total synthesis of (+)-trans- dihydronarciclasine from (+)-7-azabicyclo[2.2.1]heptanone - Pandey, Ganesh; Fernandes, Rushil; Dey, Debasis; Majumder, Binoy (Tetrahedron, 2018)
A concise asymmetric total synthesis of Amaryllidaceae alkaloid (+)-trans-dihydronarciclasine is accomplished starting from optically pure 7-azabicyclo[2.2.1]heptanone scaffold in 13 linear steps. Key features of the strategy include substrate-directed stereoselective installation of the trans B-C ring junction and regioselective Wacker-type internal olefin oxidation to provide a rapid access to all hydroxyl functionalities over the key cyclohexane ring in a stereocontrolled manner. (C) 2018 Elsevier Ltd. All rights reserved.

Tracking HOCl concentrations across cellular organelles in real time using a super resolution microscopy probe - Ali, Firoj; Aute, Sunil; Sreedharan, Sreejesh; Anila, H. A.; Saeed, Hiwa K.; Smythe, Carl G.; Thomas, Jim A.; Das, Amitava (Chemical Communications, 2018)
BODIPY derivative, SF-1, exclusively shows a fluorescence ON response to HOCl and images endogenously generated HOCl in RAW 264.7 macrophages. Widefield and super resolution structured illumination microscopy images confirm localization in the Golgi complex and lysosomes, and hence specifically detects HOCl generated in these organelles. SF-1 is compatible with 3D-SIM imaging of individual cells.

Transition-metal-catalyzed reactions involving arynes - Dhokale, Ranjeet A.; Mhaske, Santosh B. (Synthesis-Stuttgart, 2018)
The plethora of transformations attainable by the transition-metal-catalyzed reactions of arynes has found immense contemporary interest in the scientific community. This review highlights the scope and importance of transition-metal-catalyzed aryne reactions in the field of synthetic organic chemistry reported to date. It covers transformations achieved by the combination of arynes and various transition metals, which provide a facile access to a biaryl motif, fused polycyclic aromatic compounds, different novel carbocycles, various heterocycles, and complex natural products. 1 Introduction 2 Insertion of Arynes 3 Annulation of Arynes 4 Cycloaddition of Arynes 5 Multicomponent Reactions of Arynes 6 Miscellaneous Reactions of Arynes 7 Total Synthesis of Natural Products Using Arynes 8 Conclusion
Keywords: annulation; arynes; Cycloaddition; Insertion; multicomponent; Natural products; Transition Metal

Triazole-diindolylmethane conjugates as new antitubercular agents: synthesis, bioevaluation, and molecular docking - Danne, Ashruba B.; Choudhari, Amit S.; Chakraborty, Shakti; Sarkar, Dhiman; Khedkar, Vijay M.; Shingate, Bapurao B. (MedChemComm, 2018)
We describe the synthesis of novel triazole-incorporated diindolylmethanes (DIMs) using a molecular hybridization approach. The in vitro antitubercular activity of the DIMs against Mycobacterium tuberculosis H37Ra (ATCC 25177) was tested in the active and dormant state. Among all the synthesized conjugates, the compounds 6b, 6f, 6l, 6n, 6q, 6r, and 6s displayed good antitubercular activity against both the active and dormant Mtb H37Ra strain. The compound 6l exhibited good antitubercular activity against dormant Mtb H37Ra with an IC50 value of 1 g mL(-1) and IC90 (MIC) value of 3 g mL(-1). The compounds 6b, 6l, and 6r displayed good antitubercular activity against active Mtb H37Ra with IC50 values of 2.19, 1.52, and 0.22 g mL(-1), respectively. The compounds 6b, 6h, 6l, and 6s displayed more than 70% inhibition against the Gram-positive Bacillus subtilus strain at 3 g mL(-1). The molecular docking study showed the binding modes of the titled compounds in the active site of the DprE1 enzyme and assisted with elucidating a structural basis for the inhibition of Mycobacteria.

Tris-hydroxymethylaminomethane (THAM): An efficient organocatalyst in diversity-oriented and environmentally benign synthesis of spirochromenes - Khot, Supriya S.; Anbhule, Prashant V.; Desai, Uday V.; Wadgaonkar, Prakash P. (Comptes Rendus Chimie, 2018)
Tris-hydroxymethylaminomethane has been demonstrated to be an efficient organocatalyst in diversity-oriented synthesis of medicinally prevalent spirochromenes by one-pot, three-component reactions between isatins, malononitrile, and enolizable CH acids like dimedone, 4-hydroxycoumarin, 4-hydroxy-N-methylquinolin-2-one, or in situ generated 2-methylpyrazolon-2-one. Biodegradability and extremely low cost of the catalyst are the noteworthy features of this chromatography-free protocol.
Keywords: green chemistry; Multicomponent synthesis; organocatalysis; Spirochromenes; Tris-hydroxymethylaminomethane

Tuning of terahertz resonances of pyridyl benzamide derivatives by electronegative atom substitution - Dash, Jyotirmayee (Journal of Infrared, Millimeter, and Terahertz Waves, 2018)
N-(pyridin-2-yl) benzamide (Ph2AP)-based organic molecules with prominent terahertz (THz) signatures (less than 5 THz) have been synthesized. The THz resonances are tuned by substituting the most electronegative atom, fluorine, at ortho (2F-Ph2AP), meta (3F-Ph2AP), and para (4F-Ph2AP) positions in a Ph2AP molecule. Substitution of fluorine helps in varying the charge distribution of the atoms forming hydrogen bond and hence strength of the hydrogen bond is varied which helps in tuning the THz resonances. The tuning of lower THz resonances of 2F-Ph2AP, 3F-Ph2AP, and 4F-Ph2AP has been explained in terms of compliance constant (relaxed force constant). Four-molecule cluster simulations have been carried out using Gaussian09 software to calculate the compliance constant of the hydrogen bonds. Crystal structure simulations of the above molecules using CRYSTAL14 software have been carried out to understand the origin of THz resonances. It has been observed that THz resonances are shifted to higher frequencies with stronger hydrogen bonds. The study shows that 3F-Ph2AP and 4F-Ph2AP have higher hydrogen bond strength and hence the THz resonances originating due to stretching of intermolecular hydrogen bonds have been shifted to higher frequencies compared to 2F-Ph2AP. The methodology presented here will help in designing novel organic molecules by substituting various electronegative atoms in order to achieve prominent THz resonances.
Keywords: Compliance constant; Density functional theory; Ph2AP molecule; Terahertz spectroscopy

Tuning the dimensionality of layered Srn+1Tin−xNixO3n+1 perovskite structures for improved activity in syngas generation - Dama, Srikanth (Journal of Catalysis, 2018)
Interest in perovskite type oxides is growing due to their versatile catalytic applications. A series of Ruddlesden-Popper (RP) type layered perovskite oxides Srn+1Tin−xNixO3n+1 were prepared and evaluated for their catalytic activity in steam reforming, CO2 reforming and bi-reforming of methane. These materials, prepared through citrate gel method were characterized to understand their structure and Ni reducibility. Substitution of Ni in RP phases was established through refinement of XRD powder pattern. During methane reforming, the catalytic activity increased with the order of RP phase of SrTi1−xNixO3−δ (n = ∞). TPR results show variation in Ni reducibility with the order of RP phase, while TPD-O2 study helped to estimate oxygen vacancies. These vacancies seem to influence catalytic activity during methane reforming. Transient pulse experiments show that CO2 dissociates over oxygen vacancies to give CO and oxygen, with later replenishing lattice oxygen in SrTi0.8Ni0.2O3−δ (n = ∞) phases. Highly labile oxygen vacancies generated in the bulk of SrTi0.8Ni0.2O3−δ must be migrating to the surface, helping in the removal of coke formed. Characterization of catalysts after reaction helped in better understanding of coke precursors.
Keywords: Dry reforming; NickelSyngas; Ruddlesden-Popper (RP) perovskites; Steam reforming

Twelve-armed hexaphenylbenzene-based giant supramolecular framework for entrapping guest molecules - Madhu, Suresh; Gonnade, Rajesh G.; Das, Tamal; Vanka, Kumar; Sanjayan, Gangadhar J. (ChemPlusChem, 2018)
Host-guest chemistry is a functional model in supramolecular chemistry for understanding specific process occurring in biological systems. Herein, we describe a rationally designed giant multiarmed hexaphenylbenzene (HPB)-based supramolecular frameworks which encapsulate a variety of guest molecules in the voids of their crystal lattice through the cooperative interplay of multivalency, noncovalent forces and backbone rigidity. In this connection, pseudo-axially substituted twelve-armed hexaphenylbenzene was synthesized and its molecular entrapping nature was studied by varying number of H-bond donor-acceptor sites in the arms. The per-methyl esterified HPB acted as a cavitand to include nonpolar and polar aprotic guests in its crystal structure via C-H center dot center dot center dot pi, C-H center dot center dot center dot O and C-H center dot center dot center dot N interactions. The corresponding amidated HPB showed unprecedented inclusion of ammonia and segregation of the guest molecules according to their polarity in the lattice. Furthermore, this molecular entrapping system has been used to obtain the crystal structure of a hitherto unproven 2-azaallenium intermediate, which had been proposed to be involved in aminomethylation of activated arenes.

Two stereocentered HKR of anti-β,β′-diphenylpropanoxirane and anti-3-phenylethyloxiranes catalysed by Co(III)(salen)-OAc complex: enantioselective synthesis of (+)-sertraline and (+)-naproxen - Kamble, Rohit B. (New Journal of Chemistry, 2018)
The Co(III)(salen)OAc-catalyzed two stereocentered hydrolytic kinetic resolution (HKR) of anti-β,β′-diphenylmethyloxirane and anti-3-phenylethyloxiranes affords the corresponding anti-1,2-diols and oxiranes in high enantiomeric excess. The synthetic potential of this methodology is demonstrated by the enantioselective synthesis of (+)-sertraline, an antidepressant drug, and (+)-naproxen, an anti-inflammatory drug.

Ultrasound assisted synthesis of 4-(Benzyloxy)-N-(3-chloro-2-(substitutedphenyl)-4-oxoazetidin-1-yl) benzamide as challenging anti-tubercular scaffold - Nimbalkar, Urja D.; Seijas, Julio A.; Borkute, Rachna; Damale, Manoj G.; Sangshetti, Jaiprakash N.; Sarkar, Dhiman; Nikalje, Anna Pratima G. (Molecules, 2018)
A series of ten novel derivatives of 4-(benzyloxy)-N-(3-chloro-2-(substituted phenyl)-4-oxoazetidin-1-yl) benzamide 6a-j were synthesized in good yield from the key compound 4-(benzyloxy)-N-(substituted benzylidene) benzo hydrazide, called Schiff `s bases 5a-j, by Staudinger reaction ([2 + 2] ketene-imine cycloaddition reaction) with chloro acetyl chloride in the presence of catalyst tri ethylamine and solvent dimethyl formamide (DMF), by using ultra-sonication as one of the green chemistry tools. All the synthesised compounds were evaluated for in vitro anti-tubercular activity against Mycobacterium tuberculosis (MTB) and most of them showed promising activity with an IC50 value of less than 1 mu g/mL. To establish the safety, all the synthesized compounds were further tested for cytotoxicity against the human cancer cell line HeLa and all 6a-j compounds were found to be non-cytotoxic in nature. The molecular docking study was carried out with essential enzyme InhA (FabI/ENR) of Mycobacterium responsible for cell wall synthesis which suggests that 6a and 6e are the most active derivatives of the series. The theoretical evaluation of cell permeability based on Lipinski's rule of five has helped to rationalize the biological results and hence the synthesized azetidinone derivatives 6a-j were also analyzed for physicochemical evaluation that is, absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties and the results showed that all the derivatives could comply with essential features required for a potential lead in the anti-tubercular drug discovery process.
Keywords: ADMET study; anti-tubercular screening; azetidinone; cytotoxicity study; green chemistry; Molecular docking; ultra-sonication

Understanding conformational dynamics of complex lipid mixtures relevant to biology - Friedman, Ran; Khalid, Syma; Aponte-Santamaria, Camilo; Arutyunova, Elena; Becker, Marlon; Boyd, Kevin J.; Christensen, Mikkel; Coimbra, Joao T. S.; Concilio, Simona; Daday, Csaba; van Eerden, Floris J.; Fernandes, Pedro A.; et al. (Journal of membrane biology, 2018)
This is a perspective article entitled "Frontiers in computational biophysics: understanding conformational dynamics of complex lipid mixtures relevant to biology" which is following a CECAM meeting with the same name.

Understanding interactions between lignin and ionic liquids with experimental and theoretical studies during catalytic depolymerisation - Singh, Sandip Kumar; Banerjee, Subhrashis; Vanka, Kumar; Dhepe, Paresh Laxmikant (Catalysis Today, 2018)
Compared to H2SO4, Bronsted acidic ionic liquid (BAIL, [C3SO3HMIM][HSO4]) catalyzed depolymerization of lignin yielded higher concentration of low molecular weight products under mild conditions (120 degrees C) as proven by GC and GC-MS. To comprehend this disparity in catalytic activity among H2SO4 and BAIL (at similar H+ concentration), experimental techniques [1D(H-1) NMR, 2D(N-15/H-1 HMBC) NMR and RAMAN] have been employed. Based on these studies, it has been proven that the transfer of electron density from substrate to the electron deficient imidazolium ring via formation of hydrogen bond between -OH/OCH3 (substrate) and -N1C2H2N3-(cation) is possible, while the anion plays an important role. Further, density functional theory (DFT) calculations also corroborated this fact by showing a change in the bond angle and decrease in bond length (C-2-H-2 in imidazole), due to the presence of weak and strong hydrogen bonding between the substrate and IL.

Untapped bacterial diversity and metabolic potential within Unkeshwar hot springs, India - Mehetre, Gajanan T. (Archives of Microbiology, 2018)
Hot springs support diverse and interesting groups of microorganisms adapted to extreme conditions and gaining attention in biotechnological applications. However, due to limitations of cultivation methods, a majority of such extremophiles remain uncultivated and unexplored. The advent of multiple cultivation conditions and specialized culture media could possibly aid to access the unexplored microbial portion of hot springs. In the present study, different media and isolation strategies were applied to isolate hitherto unexplored bacterial taxa in the water samples collected from Unkeshwar hot springs, India. Molecular, phylogenetic and predictive functional characterization of the isolated bacterial population was done using 16S rRNA sequencing coupled with Tax4Fun tools. Furthermore, representative isolates were screened for important enzymes (cellulase, xylanase, amylase, and protease) and heavy metal tolerance (chromium, arsenic) properties. A total of 454 bacterial isolates obtained were mapped into 57 unique bacterial genera and 4 different bacterial phyla. Interestingly, 37 genera not previously isolated from Indian hot springs, were isolated for the first time in the present study. However, most of these genera (23 out of 37) were reported only in metagenomics studies from Indian and global hot springs. Furthermore, around 14 genera not previously cultivated and not detected in metagenomics studies of hot springs are documented here. The metabolic potential was ascertained by determining the abundance of specific genes using in silico based Tax4Fun tool, which identified around 315 metabolic pathways for metabolism of carbohydrates, synthesis of secondary metabolites and degradation of xenobiotic compounds. Bioprospection study revealed that 33 and 25 bacterial genera were positive for enzyme production and resistance to the heavy metals, respectively. The present study revealed the advantages of cultivation methods using a comprehensive multiple isolation approach for exploring untapped and unique bacterial diversity, and also utilities for various biotechnological and environmental applications.
Keywords: Bacterial diversity; Bioprospecting; Cultivation; Heavy metals; Untapped

Water induced morphological transformation of a poly(aryl ether) dendron amphiphile: helical fibers to nanorods, as light-harvesting antenna systems - Maity, Arunava; Dey, Ananta; Gangopadhyay, Monalisa; Das, Amitava (Nanoscale, 2018)
Self-assembly of suitable molecular building blocks is an efficient and convenient approach to generate nanomaterials with various morphologies and functions. Moreover, understanding the nature of molecules and controlling factors of their self-assembly process is crucial in fundamental aspects of molecular self-assembly which provide insights into the design of new assemblies with functional nano-architectures. To this end, the present study reports water induced self-assembled multifaceted morphology formation and the plausible pathway of the morphology transformation of a single poly(aryl ether) dendron amphiphile 1(D). In THF, 1(D) self-assembles into helical fibers. However, with an increase in the water fraction in its THF solution, the morphology changes to nanorods through an intermediate scroll-up pathway of exfoliated fibers. The nanorod formation and transformation of 1(D) are investigated using various microscopy and spectroscopy techniques, which indicate that it has highly ordered multilayered arrays of 1(D) molecules. Finally, these multilayered arrays of 1(D) nanorods are exploited for constructing a model light-harvesting system via the incorporation of small quantities of two newly designed BODIPY based molecules as energy acceptors and 1(D) as an antenna chromophore.

Water mediated proton conductance in a hydrogen-bonded Ni(II)-bipyridine-glycoluril chloride self-assembled framework - Tayade, Sakharam B.; Bhat, Satish S.; Illathvalappil, Rajith; Dhavale, Vishal M.; Kawade,Vitthal A.; Kumbhar, Avinash S.; Kurungot, Sreekumar; Näther, Christian (CrystEngComm, 2018)
Proton conducting properties have been investigated in a new Ni(II)-based hydrogen-bonded porous framework synthesized using a urea-fused bipyridine-glycoluril (BPG) tecton. This hydrogen-bonded self-assembled structure encapsulates water molecules in the channels with hydrogen-bonding networks which exhibits a significant temperature dependent proton conductance of 1.5 × 10−4 S cm−1 at 95 °C and 95% RH with a low activation energy (Ea) of 0.54 eV, implying a Grotthuss proton hopping mechanism mediated by hydrogen-bonded water molecules in the channels. In addition, this framework exhibited a very high water uptake under humid conditions. A continuous array of water molecules and chloride ions embedded in the highly hydrophilic porous channels of the hydrogen-bonded framework acts as the proton conducting medium.

WRKY1 acts as a key component improving resistance against Alternaria solani in wild tomato, Solanum arcanum Peralta - Shinde, Balkrishna A.; Dholakia, Bhushan B.; Hussain, Khalid; Aharoni, Asaph; Giri, Ashok P.; Kamble, Avinash C. (Plant Biotechnology Journal, 2018)
Early blight (EB), caused by Alternaria solani, is a major threat to global tomato production. In comparison with cultivated tomato (Solanum lycopersicum), a wild relative, S.arcanum exhibits strong resistance against EB. However, molecular cascades operating during EB resistance in wild or cultivated tomato plants are largely obscure. Here, we provide novel insight into spatio-temporal molecular events in S.arcanum against A.solani. Transcriptome and co-expression analysis presented 33-WRKYs as promising candidates of which 12 SaWRKYs displayed differential expression patterns in resistant and susceptible accessions during EB disease progression. Among these, SaWRKY1 exhibited induced expression with significant modulation in xyloglucan endotrans hydrolase 5 (XTH5) and MYB2 expressions that correlated with the disease phenotypes. Electro-mobility shift assay confirmed physical interaction of recombinant SaWRKY1 to SaXTH5 and SaMYB2 promoters. Comparative WRKY1 promoter analysis between resistant and susceptible plants revealed the presence of crucial motifs for defence mechanism exclusively in resistant accession. Additionally, many defence-related genes displayed significant expression variations in both the accessions. Further, WRKY1 overexpressing transgenic plants exhibited higher levels of EB resistance while RNAi silencing lines had increased susceptibility to A.solani with altered expression of XTH5 and MYB2. Overall, these findings demonstrate the positive influence of WRKY1 in improving EB resistance in wild tomato and this could be further utilized as a potential target through genetic engineering to augment protection against A.solani in crop plants.
Keywords: Alternaria solani; early blight; Solanum arcanum; Tomato; WRKY1; XTH5

1,6-Conjugate-addition-induced [2+1] annulation of para-quinone methides and pyrazolones: synthesis of bis-spiro compounds with contiguous quaternary spiro-centers - Kale, Someshwar B.; Jori, Popat K.; Thatikonda, Thanusha; Gonnade, Rajesh G.; Das, Utpal (Organic Letters, 2019)
A diastereoselective formal 1,6-conjugate-addition-mediated [2 + 1] annulation reaction using p-quinone methides and pyrazolones has been described. The corresponding bis-spiro[cyclohexadienone-cyclopropane-pyrazolone] compounds were obtained in very good yield under mild reaction conditions.

Adsorptive removal of chromium(VI) using spherical resorcinol-formaldehyde beads prepared by inverse suspension polymerization - Mulani, Khudbudin; Patil, Vishwanath; Chavan, Nayaku; Donde, Kamini (Journal of Polymer Research, 2019)
The spherical cross-linked beaded polymers were prepared by condensation of resorcinol and formaldehyde in presence of tri-ethylamine by inverse suspension polymerization technique. The m-cresol, aniline, urea and thiourea were used as co-monomer and polyethylene glycol (PEG 400) was used as porogen. Paraffin oil was used as non-aqueous suspension agent. The polymeric spherical beads were prepared using various types of comonomers exhibiting range of particle size 77.62 to 158.84m at 90 degrees C and 300rpm for 4h. The resulting beads were analyzed by elemental analysis, particle size analysis and scanning electron microscope (SEM). The synthesized beads were used for the removal of Cr(VI) from aqueous solutions. A simple and sensitive solid phase extraction procedure was used for the determination of chromium at trace level by spectrophotometric method using 1,5-diphenylcarbazide reagent. The adsorption of Cr(VI) on the resorcinol-formaldehyde beads was monitored by energy-dispersive X-ray spectroscopy (EDX) analysis. The metal adsorption parameters such as contact time, pH, metal ion concentration and adsorbent dose were investigated. For Cr(VI), the maximum adsorption capacity was about 99% at pH2 for the resorcinol-formaldehyde beads obtained.
Keywords: adsorption kinetics; Beads; Chromium (VI); Formaldehyde; Inverse suspension; Resorcinol

Adsorptive removal of strontium(II) using macroporous poly(AGE-co-EGDMA) beads modified with resorcin[4]arene - Mulani, K.; Patil, V.; Chavan, N.; Donde, K. (Bulletin of Materials Science, 2019)
Adsorption behaviour of strontium(II) on macroporous poly(allyl glycidyl methacrylate-co-ethylene glycol dimethacrylate) [poly(AGE-co-EGDMA)] beads modified with resorcin[4]arene was studied using macroporous cross-linked [poly(AGE-co-EGDMA)] beads. The macroporous crosslinked [poly(AGE-co-EGDMA)] beads were synthesized by suspension polymerization techniques, followed by functionalization with amino derivatives of resorcin[4]arene. The poly(AGE-co-EGDMA) beads were characterized by FTIR, 1H and 13C-NMR, elemental analysis and particle-size analysis. The surface morphology of beads was studied by scanning electron microscopy. The functionalized poly(AGE-co-EGDMA) beads were used as adsorbents for strontium removal. The crucial factors including the effect of pH, time, initial concentration of metal ions and adsorbent dose were investigated to optimize the maximum adsorption efficiency of Sr(II). The equilibrium data of strontium(II) ions adsorbed on functionalized poly(AGE-co-EGDMA) beads were analysed by pseudo-first- and pseudo-second-order kinetic models. The pseudo-second-order kinetic model indicated that strontium was adsorbed by chemisorption.
Keywords: Adsorption; AGE-EGDMA beads; resorcin[4]arene; Sr(II)

AgQDs employing black box synthetic strategy: photocatalytic and biological behavior - Pansare, Amol V.; Shedge, Amol A.; Chhatre, Shraddha Y.; Das, Debabrata; Murkute, Punam; Pansare, Shubham V.; Nagarkar, Amit A.; Patil, Vishwnath R.; Chakrabarti, S. (Journal of Luminescence, 2019)
This investigation relates FRET, photocatalytic and a biological study of AgQDs which found to be dependent on particle size and capping agent used. Surface of AgQDs was one of the most important factors that govern its activity. AgQDs with BSA binding was systematically studied by fluorescence quenching and electrostatic interaction. AgQDs mainly interacted to site II of BSA, binding distance r evaluated according to the FRET theory and was 4.6 nm for AgQDs, which suggested transfer of energy (non-radioactive) between surface modified AgQDs and biological molecule BSA. The photocatalytic activity of AgQDs for the appreciable degradation of erythrosine dye using Ultraviolet-B light was investigated. AgQDs showed specific antibacterial activity against E. coli bacterial stain. Quantum dots displayed a pronounced and specific activity causing > 50% growth of COLO-205 and MCF-7 human cancer Cells at concentrations < 10(-7 )M. Hence, present black box synthetic protocol of AgQDs could be life science application.
Keywords: AgQDs; Black box; COLO-205; Photocatalytic

Allenoate prenucleophiles: a triply diastereoselective approach to beta-hydroxy esters containing all-carbon alpha-quaternary centers - Maki, Samantha L.; Maity, Pradip; Dougherty, Shannon; Johns, Jennifer; Lepore, Salvatore D. (Organic Letters, 2019)
Allenyl esters activated by titanium(IV) underwent additions to a wide range of aldehydes in high regio- and diastereoselectivities leading to products containing an all carbon quaternary center bearing an alpha-vinyl group that was installed with high selectivity for the Z-geometry. An aldol product was also converted to an indanone offering a new route to this important compound class. Product triple diastereoselectivity has been rationalized using a concerted transition-state model.

Alpha-Angelica lactone in a new role: facile access to N-Aryl tetrahydroisoquinolinones and isoindolinones via organocatalytic alpha-CH2 oxygenation - Thatikonda, Thanusha; Deepake, Siddharth K.; Das, Utpal (Organic Letters, 2019)
A method for the direct oxidation of various N-aryl tetrahydroisoquinolines and isoindolines to the corresponding lactams using alpha-angelica lactone as a catalyst was developed. The utility of the method was further demonstrated by synthesis of indoprofen and indobufen.

Altering the O/C ratio of lignin derived monomers without sacrificing atom efficiency - Singh, Dheerendra; Dhepe, Paresh L. (ChemistrySelect, 2019)
Synthesis of platform and fuel grade chemicals from lignin without losing atom efficiency and lowering O/C ratio is a challenge in a bio-refinery concept. In this work, we report solid acid catalysed alkylation of lignin derived variety of monomers such as guaiacol, veretrole, phenol, anisole, and catechol using numerous alcohols as alkylating agents. Results elaborate that the type of acidity and structure of catalyst play important role in achieving higher dialkylated products (DAP). With 85% conversion of guaiacol, 30.9% DAP formation was achieved at 250 degrees C within 2 h. A unique substrate adsorption study on the catalyst surface and effect of solubility of substrates on the activity of catalyst is evaluated. Catalyst was observed to be recyclable with marginal loss in the activity due to handling error.
Keywords: Alcohols; Alkylation; lignin; Monomers; solid acid catalyst; Up-gradation

Alternative synthesis of the CNS stimulant Prolintane - Mujahid, M.; Korpe, G. V.; Deshmukh, S. P.; Bhadange, S. G.; Muthukrishnan, M. (Arkivoc, 2019)
An alternative synthesis of prolintane, a CNS stimulant, is reported using commercially available allyl benzene in good overall yield (32.3%). The key transformations include epoxidation, Grignard reaction, Mitsunobu and reduction protocols.

Amino acid amide based ionic liquid as an efficient organo-catalyst for solvent-free knoevenagel condensation at room temperature - Burate, Pralhad A.; Javle, Balasaheb R.; Desale, Pranjal H.; Kinage, Anil K. (Catalysis Letters, 2019)
Ionic liquids of amino acid amide were synthesized and used as an efficient catalyst for solvent-free Knoevenagel condensation. Synthesized ionic liquids are an environmentally benign, inexpensive, metal free and plays the dual role of solvent as well as an efficient catalyst for Knoevenagel condensation. A wide range of aliphatic, aromatic and heteroaromatic aldehydes easily undergo condensation with malononitrile and ethyl cyanoacetate. The reaction proceeds at room temperature without using any organic solvent and is very fast with good to excellent yield. Additionally, the catalyst is easily separable and recyclable without loss of activity. [GRAPHICS] .
Keywords: Acrylonitrile; Amino acid amide; Cyanoacrylate; Ionic liquid; Knoevenagel condensation; Solvent-free

Aromatic polyesters containing pendant azido groups: synthesis, characterization, chemical modification and thermal cross-linking - Nagane, Samadhan S.; Verma, Savita; Tawade, V, Bhausaheb; Sane, Prakash S.; Dhanmane, Sushilkumar A.; Wadgaonkar, Prakash P. (European Polymer Journal, 2019)
A partially bio-based bisphenol containing pendant azido group viz., 4,4'-(5-azidopentane-2,2-diyl) diphenol (AZBPA) was synthesized starting from 4,4'-bis (4-hydroxyphenyl) pentanoic acid. AZBPA was reacted with isophthaloyl chloride (IPC), terephthaloyl chloride (TPC) and a mixture of IPC/TPC (50:50 mol%) by phase transfer-catalyzed interfacial polycondensation route to obtain aromatic polyesters containing pendant azido groups. Copolyesters containing pendant azido groups were also synthesized by polycondensation of different molar proportions of AZBPA and commercially available 4,4'-(1-phenylethane-1,1-diyl) diphenol (BPA-AP) with IPC. Inherent viscosities and number average molecular weights of (co)polyesters were in the range 0.85-1.64 dL/g and 58,900-190,400, respectively, indicating the formation of reasonably high molecular weight polymers. Tough, transparent, and flexible films could be cast from chloroform solutions of these polyesters. X-Ray diffraction analysis showed that (co)polyesters were amorphous in nature. (Co)polyesters were characterized using FT-IR, H-1 NMR spectroscopy, XRD, TGA and DSC analysis. The chemical modification of a representative copolyester containing pendant azido groups was carried out quantitatively using copper-catalyzed azide-alkyne cycloaddition (CuAAC) with two alkynes viz., phenyl acetylene (PA) and ethynyl-4-nitrobenzene (ENB). Additionally, (co)polyesters containing pendant azido groups were thermally cross-linked (170 degrees C/12 h) leading to the formation of network structures based on azide to nitrene decomposition and subsequent reactions on polyester backbone. The selected cross-linked polyesters were characterized by stress-strain measurements. The cross-linked polymers exhibited higher tensile strength and Young's modulus and lower % elongation at break compared to corresponding pristine polyesters containing pendant azido groups.
Keywords: Aromatic polyester; Chemical modification; Click chemistry; Pendant azido group; Thermal cross-linking

Azadirachtin-A from azadirachta indica impacts multiple biological targets in cotton bollworm helicoverpa armigera - Dawkar, Vishal V.; Barage, Sagar H.; Barbole, Ranjit S.; Fatangare, Amol; Grimalt, Susana; Haldar, Saikat; Heckel, David G.; Gupta, Vidya S.; Thulasiram, Hirekodathakallu V.; Svatos, Ales.; Giri, Ashok P. (ACS Omega, 2019)
Azadirachtin-A (AzaA) from the Indian neem tree (Azadirachta indica) has insecticidal properties; however, its molecular mechanism remains elusive. The ``targeted and nontargeted proteomic profiling'', metabolomics, matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) imaging, gene expression, and in silico analysis provided clues about its action on Helicoverpa armigera. Fourth instar H. armigera larvae fed on AzaA-based diet (AzaD) suffered from significant mortality, growth retardation, reduced larval mass, complications in molting, and prolonged development. Furthermore, death of AzaD-fed larvae was observed with various phenotypes like bursting, blackening, and half-molting. Liquid chromatography-mass spectrometry (LC-MS) data showed limited catabolic processing of ingested AzaA and dramatic alternations of primary metabolism in H. armigera. MALDI-TOF imaging indicated the presence of AzaA in midgut of H. armigera. In the gut, out of 79 proteins identified, 34 were upregulated, which were related to digestion, immunity, energy production, and apoptosis mechanism. On the other hand, 45 proteins were downregulated, including those from carbohydrate metabolism, lipid metabolism, and energy transfer. In the hemolymph, 21 upregulated proteins were reported to be involved in immunity, RNA processing, and mRNA-directed protein synthesis, while 7 downregulated proteins were implicated in energy transfer, hydrolysis, lipid metabolism, defense mechanisms, and amino acid storage-related functions. Subsequently, six target proteins were identified using labeled AzaA that interacted with whole insect proteins. In silico analysis suggests that AzaA could be efficiently accommodated in the hydrophobic pocket of juvenile hormone esterase and showed strong interaction with active site residues, indicating plausible targets of AzaA in H. armigera. Quantitative polymerase chain reaction analysis suggested differential gene expression patterns and partly corroborated the proteomic results. Overall, data suggest that AzaA generally targets more than one protein in H. armigera and hence could be a potent biopesticide.

Bifunctional oxygen reduction and evolution activity in brownmillerites Ca2Fe(1- x)CoxO5 - Thundiyil, S.; Kurungot, S.; Devi, R. N. (ACS Omega, 2019)
State-of-the-art catalysts for oxygen reduction and evolution reactions (ORR and OER), which form the basis of advanced fuel cell applications, are based on noble metals such as Pt and Ir. However, high cost and scarcity of noble metals have led to an increased demand of earth-abundant metal oxide catalysts, especially for bifunctional activity in ORR and OER. The fact that Pt and Ir or C, the cost-effective alternatives suggested, do not display satisfactory bifunctional activity has also helped in turning the interest to metal oxides which are stable under both ORR and OER conditions. Brownmillerite A2B2O5 type oxides are promising as bifunctional oxygen electrocatalysts because of intrinsic structural features, viz., oxygen vacancy and catalytic activity of the B-site transition metal. In this study, Co-doped Ca2Fe2O5 compounds are synthesized by the solid state method and structurally analyzed by Rietveld refinement of powder X-ray diffraction data. The compound Ca2Fe2O5, crystallizing in the Pcmn space group has alternative FeO4 tetrahedral and FeO6 octahedral layers. Its Co-doped analogue, Ca2Fe1.75Co0.25O5, also crystallizes in the same space group with both tetrahedral and octahedral Fe positions substituted with Co. However, Ca2FeCoO5 in the Pbcm space group shows interlayer ordering with Co-rich octahedra connected to Fe-rich tetrahedra and vice versa. Oxygen bifunctional activities of these catalysts are monitored by rotating disc electrode and rotating ring disc electrode techniques in alkaline media. A close analysis of the ORR and OER was conducted through comparison of various parameters such as onset potential, current density, halfwave potential, and other kinetic parameters, which suggests that the presence of Co in the B site aids in achieving better bifunctional activity and bulk conductivity. In addition, Co(II)/Co(III) redox systems and their comparative concentrations also play a decisive role in enhancing the activity.

Bioactivities and molecular networking-based elucidation of metabolites of potent actinobacterial strains isolated from the Unkeshwar geothermal springs in India - Mehetre, Gajanan T.; Vinodh, J. S.; Burkul, Bhushan B.; Desai, D.; Santhakumari, B.; Dharne, Mahesh S.; Dastager, Syed G (RSC Advances, 2019)
The bioactive potential of Actinobacteria endemic to hot springs has rarely been investigated. This study highlights the cultivable diversity and bioactivities of Actinobacteria associated with the Unkeshwar hot springs, India. Potent strains were evaluated for their biosynthetic potentials and metabolite analysis was performed using effective dereplication molecular networking tools. A total of 86 actinobacterial strains were isolated and grouped into 21 distinct genera, based on 16S rRNA gene sequence analysis. These strains included rare members such as Micromonospora, Marmoricola, Actinomadura, Cellulomonas, Cellulosimicrobium, Janibacter, Rothia, Barrentisimonas, Dietzia and Glycomyces. In antimicrobial screening, Micromonospora sp. strain GH99 and Streptomyces sp. strain GH176 were found to be potent antimicrobial strains. The metabolic extracts of these strains exhibited strong antimicrobial activity against Staphylococcus epidermidis (NCIM 2493), Shigella flexneri (NCIM 5265), Klebsiella pneumonia (NCIM 2098), and Salmonella abony (NCIM 2257). The extracts also displayed strong anti-biofilm and anticancer activities against Pseudomonas aeruginosa (NCIM 5029), Acinetobacter junii (NCIM 5188) and breast cancer cell line MCF7, respectively. Both strains also tested positive for the presence of the PKS biosynthetic gene cluster in their genomes. To effectively delineate the secondary metabolites, the extracts were subjected to MS/MS-guided molecular networking analysis. Structurally diverse compounds including the polyketides 22-dehydroxymethyl-kijanolide (GH99 strain) and Abyssomicin I (GH176 strain) were detected in the extracts. Interestingly, Brevianamide F was detected in the extract of Micromonospora, which has previously been mostly found in fungal species. Other compounds such as cyclic tripeptides, Cyclo(l-Pro-d-Ile) and Cyclo(d-Pro-l-Phe), were also identified in this strain. In summary, for the first time, we explored the diversity of Actinobacteria and evaluated their bioactive potential from the Unkeshwar hot springs. The potent strains isolated in the study could be useful in drug discovery programs.

Biochemical and molecular aspects of dimorphism in fungi - Pathan, Ejaj K.; Ghormade, Vandana; Panmei, Redeemson; Deshpande, Mukund V. (Advancing Frontiers in Mycology & Mycotechnology, 2019)
Most of the eukaryotic differentiation processes are unidirectional. However, fungi have the ability to grow reversibly as unicellular yeast (Y) or as filamentous hypha (H) in response to the specific strain-dependent environmental stimuli. Such a phenomenon known as “dimorphism” is not limited to a specific class of fungi. Most of the plant, human, and insect pathogenic fungi show Y-H and reversible morphogenesis, associated with their saprophytic to pathogenic change, for survival and proliferation in the host. In this chapter, we have described the factors stimulating dimorphism, the signal transduction pathways induced by these stimuli, changes in the gene/protein expression patterns due to a cascade of these signals, and, finally, translation of this genotypic effect into phenotypic change, i.e., the morphological outcome. The process of fungal differentiation and formation of tumor cells follow the same regulatory series of events, involving cAMP, MAP, and RAS kinase cascades. Therefore, the molecules inhibiting Y-H transition in fungi can be explored for their anticancer potential.

Biodegradation of mixed polycyclic aromatic hydrocarbons by pure and mixed cultures of biosurfactant producing thermophilic and thermo-tolerant bacteria - Mehetre, Gajanan T.; Dastager, Syed G.; Dharne, Mahesh S. (Science of the Total Environment, 2019)
Applicability of thermophilic and thereto-tolerant microorganisms for biodegradation of polycyclic aromatic hydrocarbons (PAHs) with low water solubility is an interesting strategy for improving the biodegradation efficiency. In this study, we evaluated utility of thermophilic and thermo-tolerant bacteria isolated from Unkeshwar hot spring (India) for biodegradation of four different PAHs. Water samples were enriched in mineral salt medium (MSM) containing a mixture of four PAHs compounds (anthracene: ANT, fluorene: FLU, phenanthrenc: PHE and pyrene: PYR) at 37 degrees C and 50 degrees C. After growth based screening, four potent strains obtained which were identified as Aeribacillus pallidus (UCPS2), Bacillus axarquiensis (UCPD1), Bacillus siamensis (GHP76) and Bacillus subtilis subsp. inaquosorum (U277) based on the 16S rRNA gene sequence analysis. Degradation of mixed PAH compounds was evaluated by pure as well as mixed cultures under shake flask conditions using MSM supplemented with 200 mg/L concentration of PAHs (50 mg/L of each compound) for 15 days at 37 degrees C and 50 degrees C. A relatively higher degradation of ANT (92% - 96%), FLU (83% - 86%), PHE (16% - 54%) and PYR (51% - 71%) was achieved at 50 degrees C by Aeribacillus sp. (UCPS2) and mixed culture. Furthermore, crude oil was used as a substrate to study the degradation of same PAHs using these organisms which also revealed with similar results with the higher degradation at 50 degrees C. Interestingly, PAH-degrading strains were also positive for biosurfactant production. Biosurfactants were identified as the variants of surfactins (lipopeptide biosurfactants) based on analytical tools and phylogenetic analysis of the surfactin genes. Overall, this study has shown that hot spring microbes may have a potential for PAHs degradation and also biosurfactant production at a higher temperature, which could provide a novel perspective for removal of PAHs residues from oil contaminated sites. (C) 2019 Elsevier B.V. All rights reserved.
Keywords: Biodegradation; Biosurfactants; Crude oil; Mixed culture; PAHs; Thermophiles

Biodegradation of squalene and n-hexadecane by Gordonia amicalis HS-11 with concomitant formation of biosurfactant and carotenoids - Sowani, Harshada; Deshpande, Ashish; Gupta, Vidya; Kulkarni, Mohan; Zinjarde, Smita (International Biodeterioration & Biodegradation, 2019)
Gordonia amicalis HS-11 has been enriched from a hydrocarbon contaminated tropical soil sample. The ability of this organism to utilize a triterpenic polyunsaturated hydrocarbon, squalene (2,6,10,15,19,23-hexamethyl-6,6,10,14,18,20-tetracosahexane) and the model saturated hydrocarbon n-hexadecane is described here. The isolate degraded squalene and n-hexadecane (79 +/- 3.02 and 96 +/- 4.11%, respectively) after eight days of incubation. The isolate produced an extracellular biosurfactant that reduced surface tension from 69 +/- 2.83 to 40 +/- 1.63 and 35 +/- 2.34 mN m(-1) with squalene and n-hexadecane as carbon sources, respectively, after 6 days. The Actinomycete cleaved squalene to geranylacetone and famesyl acetaldehyde that were further utilized for supporting growth. n-Hexadecane was degraded via monoterminal oxidation and activities of important enzymes (alkane hydroxylase and alcohol dehydrogenase) were highest (215 +/- 8.76 and 169 +/- 6.02 units mg(-1) protein, respectively) after four days. Cells grown on squalene were short and with n-hexadecane there were clumps of longer cells. Squalene and n-hexadecane-grown cell surfaces were smooth possibly due to extracellular surface active compounds. While growing on hydrophobic substrates, some cells were seen adhering to droplets and others were in the free form. The culture was able to simultaneously degrade hydrocarbons and produce two commercially relevant value-added products. The yield of the extracellular biosurfactant on n-hexadecane was 480 mg l(-1) and cells grown on squalene and n-hexadecane also yielded carotenoids (2.3 +/- 0.14 and 2.9 +/- 0.10 mg g(-1) dry cell weight, respectively). This is the first report on the utilization of squalene by Gordonia.
Keywords: Aerobic biodegradation; Carotenoids; Catabolic pathways; Emulsifier; Gordonia amicalis HS-11

Biopolymer/glycopolypeptide-blended scaffolds: synthesis, characterization and cellular interactions - Dhaware, Vinita; Diaz, David Diaz; Sen Gupta, Sayam (Chemistry-An Asian Journal, 2019)
Three-dimensional (3D) scaffolds formed from natural biopolymers gelatin and chitosan that are chemically modified by galactose have shown improved hepatocyte adhesion, spheroid geometry and functions of the hepatocytes. Galactose specifically binds to the hepatocytes via the asialoglycoprotein receptor (ASGPR) and an increase in galactose density further improves the hepatocyte proliferation and functions. In this work, we aimed to increase the galactose density within the biopolymeric scaffold by physically blending the biopolymers chitosan and gelatin with an amphiphlic beta-galactose polypeptide (PPO-GP). PPO-GP, is a di-block copolymer with PPO and beta-galactose polypeptide, exhibits lower critical solution temperature and is entrapped within the scaffold through hydrophobic interactions. The uniform distribution of PPO-GP within the scaffold was confirmed by fluorescence microscopy. SEM and mechanical testing of the hybrid scaffolds indicated pore size, inter connectivity and compression modulus similar to the scaffolds made from 100 % biopolymer. The presence of the PPO-GP on the surface of the scaffold was tested monitoring the interaction of an analogous mannose containing PPO-GP scaffold and the mannose binding lectin Con-A. In vitro cell culture experiments with HepG2 cells were performed on GLN-GP and CTS-GP and their cellular response was compared with GLN and CTS scaffolds for a period of seven days. Within three days of culture the Hep G2 cells formed multicellular spheroids on GLN-GP and CTS-GP more efficiently than on the GLN and CTS scaffolds. The multicellular spheroids were also found to infiltrate more in GLN-GP and CTS-GP scaffolds and able to maintain their round morphology as observed by live/dead and SEM imaging.
Keywords: adhesion; Aggregates; Cellular infiltration; Spheroids

Bioprospecting of fungal entomo- and myco-pathogens - Pathan, E. K.; Patil, A. V.; Deshpande, M. V. (Advancing Frontiers in Mycology & Mycotechnology, 2019)
The pest and pathogen control in the field using fungi and their metabolites has indeed gone beyond ‘proof of concept’. However, in view of the performances of these biocontrol fungi in the fields, moreover, acceptability by the end users regarding cost-effectiveness, shelf life, intellectual property rights (IPR), the additional roles, and possible applications are being explored. Dual pathogenicity, viz. entomopathogenesis and mycoparasitism, has added the advantage of wide-spectrum biocontrol in single-crop system. In addition to plant protection, these fungi can promote plant growth. Further, in integrated pest management, the bioremediation of pesticide residues, if any, can also be achieved by these organisms. For value addition, use of cuticle-degrading and mycolytic enzymes produced as killing components can be explored in food, detergent, organic synthesis, and pharmaceutical industries. While exploring the additional applications, the safety to beneficial insects and fungi, biodiversity, and humans, in general, is also addressed.

Biosynthesized Co-doped TiO2 nanoparticles based anode for lithium-ion battery application and investigating the influence of dopant concentrations on its performance - Kashale, A. A.; Rasal, A. S.; Kamble, G. P.; Ingole, V. H.; Dwivedi, P. K.; Rajoba, S. J.; Jadhav, L. D.; Ling, Y. C.; Chang, J. Y.; Ghule, A. V. (Composites Part B: Engineering, 2019)
TiO2 is a good alternative anode material for lithium-ion battery application because of its incomparable high structural stability and safety during the charge/discharge cycles. However, the low intrinsic conductivity of TiO2 has been a limiting factor affecting its cycling and rate capability performance. Here in this work, we present Co-doped TiO2 nanoparticles based anode with good reversibility, cycling stability and rate capability performance for its envisaged application in lithium-ion battery. The Co-doped TiO2 nanoparticles with different Co concentrations (3%, 5%, and 7%) are synthesized using simple and economic biomediated green approach, wherein TiCl4 and Co precursors are allowed to react in Bengal gram bean extract containing biomolecules which act as natural capping agents to control the size of nanoparticles. Among the pure TiO2 and different Co-doped TiO2 samples, the 7% Co-doped TiO2 anode show the highest capacity of 167 mAh g−1 (88.3%) after 100 cycles at the 0.5C current density. The Co-doped TiO2 shows higher and stable coulombic efficiency up to 100 GCD cycles indicating good reversibility. Based on the results, it is expected that the Co-doped TiO2 nanoparticles might be contributing to the enhanced electronic conductivity providing an efficient pathway for fast electron transfer.

Boron-conjugated pyrenes as fluorescence-based molecular probes and security markers - Wakchaure, Vivek Chandrakant; Das, Tamal; Babu, Sukumaran Santhosh (ChemPlusChem, 2019)
Boron-embedded aromatic hydrocarbons are a class of molecules known for their distinct electronic and/or optoelectronic properties and are thus suitable for many potential applications. Among those, boronic ester and acid containing molecules have been widely used for sensing and molecular recognition applications, respectively. We compared the sensing and molecular recognition properties of two boron-containing pyrene derivatives for fluoride and glucose sensing applications. The presence of four boronate ester groups enabled fluoride ion sensing at the mu M level. The boronic acid derivative is very selective towards glucose compared to other saccharides. Furthermore, we used the mechano-responsive fluorescence changes and self-assembly of these derivatives, respectively, for fluorescence-based inkless and ink (water)-based writing in invisible security labeling applications.
Keywords: boron; carbohydrates; mechanoluminescence; pyrene; sensors

Catalytic hydrogenation products of aromatic and aliphatic dicarboxylic acids - Shinde, Sunil; Deshpande, Raj M. (Asian Journal of Chemistry, 2019)
Hydrogenation of aromatic dicarboxylic acids gave 100 % selectivity to respective cyclohexane dicarboxylic acid with 5 % Pd/C catalyst. 5 % Ru/C catalyst was observed to give over hydrogenation products at 493 K and at lower temperature (453 K) the selectivity for cyclohexane dicarboxylic acids was increased. Hydrogenation of phthalic acid with Ru-Sn/Al2O3 catalyst was observed to give phthalide instead of 1,2-benzene dimethanol or 2-hydroxy methyl benzoic acid. Ru-Sn/Al2O3 catalyst selectively hydrogenated the carboxylic group of cyclohexane dicarboxylic acids to give cyclohexane dimethanol. Use of proper catalysts and reaction conditions resulted in desired products.

Characterization of novel acidic and thermostable phytase secreting Streptomyces sp. (NCIM 5533) for plant growth promoting characteristics - Puppala, K. R.; Bhavsar, K.; Sonalkar, V.; Khire, J. M.; Dharne, M. S. (Biocatalysis and Agricultural Biotechnology, 2019)
Successful agricultural practices in acidic and arid region soils are still challenging worldwide. We investigated Actinomycete strain obtained from soil, which was found to produce extracellular phytase having the optimum pH, temperature of 2.5 and 70 °C, respectively and Plant growth promoting (PGP) attributes. These abilities of the phytase make it novel as compared to other Streptomyces derived phytases. Strain was also evaluated for physiological traits such as salinity, temperature, and pH followed by morphological and molecular identification. The Streptomyces sp. strain (NCIM 5533) displayed additional PGP traits such as indole-3-acetic acid (IAA), ammonia and phosphate solubilization activity. A significant increment in Tomato plant (Solanum lycopersicum) root, shoot and as well as total height in bioassays at laboratory scale and green house level and its ability to colonize roots substantiated its potency as a true plant growth promoting rhizobacteria (PGPR). To our knowledge this is the first report of Streptomyces sp. having the ability to produce acidic and thermostable phytase as well as PGP traits showing enhanced plant growth could have implications in soils having acidic nature and also in arid region.

Chiral separation of styrene oxides supported by enantiomeric tetrahedral neutral Pd(II) cages - Rajasekar, Prabhakaran; Pandey, Swechchha; Ferrara, Joseph D.; Del Campo, Mark; Le Magueres, Pierre; Boomishankar, Ramamoorthy (Inorganic Chemistry, 2019)
The separation of enantiomers is of considerable importance in the preparation of the compounds of biological interests, catalysis, and drug development. Here, we report a novel enantioseparation of styrene epoxides (SOs) resolved in the presence of a pair of enantio-enriched tetrahedral cages. Chiral neutral cages of formula [(Pd3X*)(4)(C6O4Cl2)(6)] ([X*](3-) = RRR-or SSS-[PO(N(*CH(CH3)Ph)(3)](3)) are constructed from Pcl, building units supported by tris(imido)phosphate trianions and chloranilate linkers. These cages exhibit considerable enantioselective separation capabilities toward a series of styrene epoxides via a crystallization inclusion method. A highest enantiomeric excess (ee) value of up to 80% is achieved for the (R)-4-fluorostyrene oxide.

Comparative study of a class of mean field theories of the glass transition - Saha, Indranil; Nandi, Manoj Kumar; Dasgupta, Chandan; Bhattacharyya, Sarika Maitra (Journal of Statistical Mechanics-Theory and Experiment, 2019)
In a recently developed microscopic mean field theory, we have shown that the dynamics of a system, when described only in terms of its pair structure, can predict the correct dynamical transition temperature. Further, the theory predicted the difference in dynamics of two systems (the Lennard-Jones and the Weeks-Chandler-Andersen) despite them having quite similar structures. This is in contrast to the Schweizer-Saltzman (SS) formalism which predicted the dynamics of these two systems to be similar. The two theories although similar in spirit have certain differences. Here we present a comparative study of these two formalism to find the origin of the difference in their predictive power. We show that not only the dynamics in the potential energy surface, as described by our earlier study, but also that in the free energy surface, like in the SS theory, can predict the correct dynamical transition temperature. Even an approximate one component version of our theory, similar to the system used in the SS theory, can predict the transition temperature reasonably well. Interestingly, we show here that despite the above mentioned shortcomings the SS theory can actually predict the correct transition temperatures. Thus microscopic mean field theories of this class which express dynamics in terms of the pair structure of the liquid while being unable to predict the actual dynamics of the system are successful in predicting the correct dynamical transition temperature.
Keywords: aging; etc); glasses (colloidal; glassy dynamics; mode coupling theory; Polymer; slow relaxation

Concise formal synthesis of (-)-(6R,11R,14R)-colletallol via D-proline catalysed alpha-aminooxylation-Wittig olefination strategy - Dey, Soumen; Gadakh, Sunita; Sudalai, Arumugam (Indian Journal of Chemistry Section B-Organic Chemistry Including Medicinal Chemistry, 2019)
An efficient enantioselective formal synthesis of marine macrolide (-)-(6R,11R,14R)-colletallol has been achieved starting from commercially available raw materials. The key reactions include the D-proline catalyzed a-aminooxylation of aldehyde followed by Horner-Wardsworth-Emmons olefination in a sequential fashion to give the macrolide key intermediate 5 in high enantiomeric purity (97% ee) and high overall yield (32%).
Keywords: alpha-aminoxylation; Asymmetric synthesis; Enantioselectivity; Natural products; organocatalysis

Conversion of curved assemblies into two dimensional sheets - Deshmukh, Gunvant; Krishnamoorthy, Kothandam (Nanoscale, 2019)
The design and preparation of organic two dimensional (O2D) sheets and their conversion to curved nanostructures is in its infancy. To convert a flat structure into a curved structure, the molecule must have multiple interaction possibilities and an in-built twist. The conjugated small molecule iso-Indigo (i-Indigo) comprises two phenyl rings that are twisted (the dihedral angle is 15 degrees) at the junction. The i-Indigo has been connected with moieties that impart hydrogen bonding and van der Waals interactions. Due to the presence of the cloud in i-Indigo, - interactions are also present in the molecule. While all three interactions are in operation, rings and toroids are formed. Upon addition of hydrogen bonding competing solvents, the rings and toroids unravel to form O2D sheets. Control molecules that don't have hydrogen bonding moieties and - interactions form random assemblies. Please note that the rings, toroids and O2D sheets are formed in a single solvent by simple dissolution, unlike previous approaches that involve multiple steps and solvents.

Covalent organic frameworks: chemistry beyond the structure - Kandambeth, Sharath; Dey, Kaushik; Banerjee, Rahul (Journal of the American Chemical Society, 2019)
Covalent organic frameworks (COFs) represent a new field of rapidly growing chemical research that takes direct inspiration from diverse covalent bonds existing between atoms. The success of linking atoms in two and three dimensions to construct extended framework structures moved the chemistry of COFs beyond the structures to methodologies, highlighting the possibility of prospective applications. Although structure to property relation in COFs has led to fascinating properties, chemical stability, processability and scalability were some of the important challenges that needed to be overcome for their successful implementation. In this Perspective, we take a closer look at the growth of COFs from mere supramolecular structures to potential industrializable materials.

Covalent self-assembly in two dimensions: connecting covalent organic framework nanospheres into crystalline and porous thin films - Sasmal, Himadri Sekhar; Halder, Arjun; Kunjattu, Shebeeb; Dey, Kaushik; Nadol, Athulya; Ajithkumar, Thalasseril G.; Bedadur, Prachiti Ravindra; Banerjee, Rahul (Journal of the American Chemical Society, 2019)
Insolubility of covalent organic frameworks (COFs) in organic solvents is one of the major obstacles for the potential application of these extended networks such as drug delivery, sensing, optoelectronics, and semiconductor device fabrication. The present work proposes a unique way to make uniform, solution-processable, crystalline, and porous COF nanospheres directly from the homogeneous solution of amine and aldehyde via spatial and temporal control of the nucleation and growth. This strategy of direct nucleation simultaneously showcases the caliber to tune the size of the COF nanospheres from 25 to 570 nm. We have also demonstrated the concept of mesoscale covalent self-assembly of those solution-processable COF nanospheres in the liquid-liquid interface (DCM-water bilayer) for the very first time, transmuting them into self-standing COF thin films with long-range ordered arrangements in two dimensions. The crystalline and porous (with TpAzo showing highest S-BET of 1932 m(2) g(-1)) free-standing COF thin films could be fabricated in a wide range of thicknesses from as low as 21 nm to as high as 630 nm. Both beta-ketoenamine (TpAzo, TpDPP) and imine (TpOMeAzo, TpOMeDPP) linked COF thin films have been synthesized via mesoscale covalent self-assembly of the solution-processable COF nanospheres illustrating the generality of this eloquent methodology. Further, the solution processability has been tested and utilized to cast COF thin films uniformly in the inner and outer surface of an alumina hollow fiber membrane. The COF thin film-alumina hollow fiber membrane composites have showcased promising selective molecular separation of He and O-2, He and CO2, and He and N-2.

Crystal engineering: an outlook for the future - Nangia, Ashwini K.; Desiraju, Gautam R. (Angewandte Chemie-International Edition, 2019)
Crystal Engineering has traditionally dealt with molecular crystals. It is the understanding of intermolecular interactions in the context of crystal packing and in the utilization of such understanding in the design of new solids with desired physical and chemical properties. We outline here five areas which come under the umbrella of Crystal Engineering and where we feel that a proper planning of research efforts could lead to higher dividends for science together with greater returns for humankind. We touch on themes and domains where science funding and translation efforts could be directed in the current climate of a society that increasingly expects applications and utility products from science and technology. The five topics are: 1)pharmaceutical solids; 2)industrial solid state reactions; 3)mechanical properties with practical applications; 4)MOFs and COFs framework solids; 5)new materials for solar energy harvesting and advanced polymers.
Keywords: crystal engineering; metal-organic frameworks; pharmaceutical solids; solar energy; solid-state reactions

Cyclic tetrapeptides from nature and design: a review of synthetic methodologies, structure, and function - Sarojini, Vijayalekshmi; Cameron, Alan J.; Varnava, Kyriakos G.; Denny, William A.; Sanjayan, Gangadhar (Chemical Reviews, 2019)
Small cyclic peptides possess a wide range of biological properties and unique structures that make them attractive to scientists working in a range of areas from medicinal to materials chemistry. However, cyclic tetrapeptides (CTPs), which are important members of this family, are notoriously difficult to synthesize. Various synthetic methodologies have been developed that enable access to natural product CTPs and their rationally designed synthetic analogues having novel molecular structures. These methodologies include the use of reversible protecting groups such as pseudoprolines that restrict conformational freedom, ring contraction strategies, on-resin cyclization approaches, and optimization of coupling reagents and reaction conditions such as temperature and dilution factors. Several fundamental studies have documented the impacts of amino acid configurations, N-alkylation, and steric bulk on both synthetic success and ensuing conformations. Carefully executed retrosynthetic ring dissection and the unique structural features of the linear precursor sequences that result from the ring dissection are crucial for the success of the cyclization step. Other factors that influence the outcome of the cyclization step include reaction temperature, solvent, reagents used as well as dilution levels. The purpose of this review is to highlight the current state of affairs on naturally occurring and rationally designed cyclic tetrapeptides, including strategies investigated for their syntheses in the literature, the conformations adopted by these molecules, and specific examples of their function. Using selected examples from the literature, an in-depth discussion of the synthetic techniques and reaction parameters applied for the successful syntheses of 12-, 13-, and 14-membered natural product CTPs and their novel analogues are presented, with particular focus on the cyclization step. Selected examples of the three-dimensional structures of cyclic tetrapeptides studied by NMR, and X-ray crystallography are also included.

Data on metabolic profiling of spongy tissue disorder in Mangifera indica cv. Alphonso - Oak, P. S.; Deshpande, A. B.; Pujari, K. H.; Prabhudesai, S. S.; Giri, A. P.; Gupta, V. S. (Data in Brief, 2019)
Data in this article presents aroma volatiles and fatty acids composition of mesocarp specific malady namely spongy tissue disorder in Mangifera indica cv. Alphonso. Quantitative changes in various aroma volatile compound classes as well as saturated and unsaturated fatty acids in spongy tissue vis-à-vis healthy mesocarp have been analyzed throughout the development of the disorder. Statistical data analysis correlates the dynamic changes in the aroma volatiles composition to that of the modulation in the fatty acids profile.

Depolymerization of lignin using a solid base catalyst - Chaudhary, Richa; Dhepe, Paresh L. (Energy & Fuels, 2019)
Lignin extraction from lignocellulosic biomass has attracted considerable attention for an alternative production of sustainable fuels and chemicals. We report the lignin isolation from coconut coir using Klason, organosolv, and soda methods and the depolymerization of isolated lignin to value-added chemicals using a solid base catalyst. The yield of isolated lignin by the Klason method was found to be about 4 to 6 times higher than that by other methods. The structure of isolated Klason lignin (CC-KL), organosolv lignin (CC-ORGL), and soda lignin (CC-SL) was studied using attenuated total reflection (ATR), NMR, microanalysis, and so forth. The monomer molecular formula derived from microanalysis suggested that coir lignin is rich in guaiacyl units. ATR and C-13 NMR clearly indicate that CC-ORGL contains more C-C bonds compared to CC-KL and CC-SL. Subsequently, these isolated lignins were depolymerized over a solid base catalyst (NaX) under atmospheric pressure. CC-SL shows a high yield of aromatic products (28%) compared to CC-ORGL and CC-KL. In order to develop a sustainable future technology, one-pot depolymerization of coconut coir was performed which resulted in a high yield (64%) of aromatic products.

Descriptors to predict dye-sensitized semiconductor based photocatalyst for hydrogen evolution reaction - Sappati, Subrahmanyam; George, Leena; Swamy, Vincent Paul; Devi, R. Nandini; Ghosh, Prasenjit (ChemCatChem, 2019)
Discovering efficient photocatalysts for hydrogen production from water splitting is highly desirable. Computational studies can help in rational designing of such catalysts through high throughput screening of materials. However, for that purpose one needs to identify descriptors that not only connects material properties with their functionality but are easy and inexpensive to compute. Using a combination of density functional theory based calculations and experiments we show two descriptors, namely, charge injection efficiency and electron hole separation, that can be used for in silico design of new and efficient dye-sensitized-semiconductor composites as catalysts for hydrogen evolution reaction.
Keywords: charge injection; descriptor; dye-sensitized semiconductors; electron-hole separation; H-2 evolution

Design and synthesis of aromatic polyesters bearing pendant clickable maleimide groups - Nagane, Samadhan S.; Kuhire, Sachin S.; Jadhav, Uday A.; Dhanmane, Sushilkumar A.; Wadgaonkar, Prakash P. (Journal of Polymer Science Part A-Polymer Chemistry, 2019)
A bisphenol bearing pendant maleimide group, namely, N-maleimidoethyl-3, 3-bis(4-hydroxyphenyl)-1-isobenzopyrrolidone (PPH-MA) was synthesized starting from phenolphthalein. Aromatic (co)polyesters bearing pendant maleimide groups were synthesized from PPH-MA and aromatic diacid chlorides, namely, isophthaloyl chloride (IPC), terephthaloyl chloride (TPC), and 50:50 mol % mixture of IPC and TPC by low temperature solution polycondensation technique. Copolyesters were also synthesized by polycondensation of different molar proportions of PPH-MA and bisphenol A with IPC. Inherent viscosities and number-average molecular weights of aromatic (co)polyesters were in the range of 0.52-0.97 dL/g and 20,200-32,800 g/mol, respectively indicating formation of medium to reasonably high-molecular-weight polymers. C-13 NMR spectral analysis of copolyesters revealed the formation of random copolymers. The 10% weight loss temperature of (co)polyesters was found in the range 470-484 degrees C, indicating their good thermal stability. A selected aromatic polyester bearing pendant maleimide groups was chemically modified via thiol-maleimide Michael addition reaction with two representative thiol compounds, namely, 4-chlorothiophenol and 1-adamantanethiol to yield post-modified polymers in a quantitative manner. Additionally, it was demonstrated that polyester containing pendant maleimide groups could be used to form insoluble crosslinked gel in the presence of a multifunctional thiol crosslinker. (c) 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 630-640
Keywords: crosslinking; maleimide group; modification; polyesters; thiol-maleimide

Designing multifunctional MOFs using an inorganic motif [Cu3(μ3-OH)(μ-Pyz)] as SBU and their properties - Akhtar, S.; Bala, S.; De, A.; Das, K. S.; Adhikary, A.; Jyotsna, S.; Poddar, P.; Mondal, R. (Crystal Growth & Design, 2019)
In a continuation of our interest in pyrazole-based multifunctional metal-organic frameworks (MOFs), we report herein the construction of a series of Cu(II) MOFs using pyrazole and various 5-substituted isophthalic acids. The central theme is to generate MOFs using the crystal engineering strategy of spacer and node; however, for the node we have introduced a well-known inorganic motif, a [Cu-3(mu(3)-OH)(mu-Pyz)(3)] unit. The appearance of the SBU in five MOFs confirms the robustness and reproducibility of the motif with some interesting structures of various dimensionality ranging from 1D helical and 2D herringbone grid to a complex 3D framework. The deployment of bent acids brings chirality via helicity in the system, as further confirmed by solid-state CD spectra. A detailed investigation of the porous MOFs reveals their importance as zeolite analogues for environment remediation. MOF-1-MOF-5 show some interesting photodegradation of harmful organic dyes. MOF-4 and MOF-5 show impressive selective CO2 gas sorption properties. Furthermore, magnetic properties associated with the trinuclear and hexanuclear SBUs of MOF-1 and MOF-3-MOF-5 have also been investigated.

Detection of toxic metal ions Pb2+ in water using SiO2@Au core-shell nanostructures: A simple technique for water quality monitoring - Daware, Krishna; Kasture, Manasi; Kalubarme, Ramchandra; Shinde, Rakesh; Patil, Kashinath; Suzuki, Norihiro; Terashima, Chiaki; Gosavi, Suresh; Fujishim, Akira (Chemical Physics Letters, 2019)
The present paper demonstrates a development of simple, sensitive and selective optical probe for detection of Pb2+ ions in water using monodispersed silica-gold core-shell nanostructures (SiO2@Au NSs). Structural and elemental analysis confirms the phase purity of nanostructures. The SPR studies for SiO2 @Au NSs reveals, linear dynamic range for Pb2+ ions detection, in the concentration range of 100 ppb to 2 ppm, with detection limit of 100 ppb, which is 5 times higher than AuNPs. Cross sensitivity study confirm its selectivity towards Pb2+ ions over other metal ions. XPS analysis shows the interaction of Pb2+ ions with core-shell NPs.

Development and evaluation of taxon-specific primers for the selected Caudovirales taxa - Newase, Sandeep K.; Gupta, Alka; Dastager, Syed G.; Kapadnis, Balu P.; Shashidhar, Ravindranath (Virus Research, 2019)
The phage taxonomy is primarily based on the morphology derived from Transmission Electron Microscopic (TEM) studies. TEM based characterization is authentic and accepted by scientific community. However, TEM based identification is expensive and time consuming. After the phage isolation, before analysis TEM, a DNA based rapid method could be introduced. The DNA based method could dramatically reduce the number of samples analyzed by TEM and thereby increase the speed and reduce the cost of identification. In the present work, four environmental phage isolates were identified based on TEM studies and genome size. The identification of these four phages was validated using DNA based method. The taxon-specific DNA markers were identified through multiple sequence alignments. The primers were designed at conserved genes (DNA polymerase or integrase) of 4 different phage taxa viz. family Ackermannviridae, genus Jerseyvirus, genus T4virus, and genus P22virus. These primers were evaluated using both in vitro and in silico approach for the amplification of the target taxons. Majority of the primer sets were found to amplify member species of the targeted taxa in vitro. In In silico analysis, six primer sets intended for identification of family Ackermannviridae showed positive amplification of >= 86.7% classified species. Further, the primers targeting the genus Jerseyvirus and T4virus showed the amplification of 53.8% and >= 84.6% species, respectively. The present work is a case study performed to explore the possibility of use of taxon-specific primers for identification and taxonomic studies of newly isolated phages to supplement the TEM.
Keywords: Bacteriophage; DNA markers; Pcr; Primers; Taxonomy; TEM

Development of low-cost plant probiotic formulations of functional endophytes for sustainable cultivation of Coleus forskohlii - Mastan, Anthati; Rane, Digeshwar; Dastager, Syed; VivekBabu, C. S. (Microbiological Research, 2019)
Deployment of plant endophytes at field level is reported to make an impact on agricultural crop productivity; development and deployment of suitable crop specific plant probiotics in a suitable delivery matrix is a value-added task. In our study, we attempted to develop bioformulations of native, fungal endophytes of Coleus forskohlii to improve plant yield using two different carrier-based materials (talc and wheat bran). Initially, fungal endophytes (RF1, SF1, and SF2) were grown on sterilized wheat bran under solid state condition and their growth kinetics and pattern were analyzed by ergosterol content and scanning electron microscope, respectively. 10-day-grown fungal endophytic cultures were used for the development of two types of formulations (wheat bran and talc-based formulations) and tested for their efficacy on host plant, C. forskohlii under field conditions. Interestingly, application of wheat bran-based endophytic formulations significantly (p < 0.01) enhanced plant height (12-29%), number of branches (51-63%), root biomass (26-33%), photosynthetic pigments (32-101%), and forskolin content (35-56%) compared to talc-based formulations under field conditions. Shelf life of endophytes (RF1, SF1, and SF2) in both formulations revealed spore viability in wheat bran-based formulations for 6 months storage period as compared to talc-based formulations. Overall, the present investigation envisages developing plant probiotic bioformulations of functional endophytes of C. forskohlii to enhance root biomass and in planta forskolin content.

Devising chemically robust and cationic Ni(II)-MOF with nitrogen-rich micropores for moisture-tolerant CO2 capture: highly regenerative and ultrafast colorimetric sensor for TNP and multiple Oxo-anions in water with theoretical revelation - Goswami, Ranadip; Seal, Nilanjan; Dash, Soumya Ranjan; Tyagi, Anshu; Neogi, Subhadip (ACS Applied Materials & Interfaces, 2019)
Metal-organic frameworks (MOFs) show distinctive superiority for carbon dioxide (CO2) capture and luminescent sensing of toxic pollutants over other materials where combination of both of these properties together with improvement of hydrolytic stability and pore functionality is critical to environmental remediation applications. The Ni(II) framework [Ni-2(mu 2OH)(azdc)(tpim)](NO3)center dot 6DMA center dot 6MeOH (CSMCRI-3) (tpim = 44'4(2)-(1H-imidazole-245-triyl)tripyridine H(2)azdc = azobenzene-44'-dicarboxylic acid DMA = dimethylacetamide CSMCRI = Central Salt & Marine Chemicals Research Institute) encompassing cationic [Ni-2(mu(2)-OH)(CO2)(2)] SBUs is solvothermally synthesized from nitrogen-rich and highly fluorescent organic struts. The noninterpenetrated structure containing free nitrogen atom affixed microporous channels is stable in diverse organic solvents and weakly basic and acidic aqueous solutions. The activated MOF (3a) exhibits strong CO2-framework interaction and extremely selective CO2 adsorption over N-2 (292.5) and CH4 (11.7). Importantly water vapor exposure does not affect the surface area and/or multiple CO2 uptake-release cycles signifying potential of the porous structure for long-term use under humid conditions. Aqueous-phase sensing studies illustrate extremely specific and ultrafast detection of explosive 246-trinitrophenol (TNP) via remarkable fluorescence quenching (K-SV = 1.3 x 10 (5) M-1) with a 0.25 ppm limit of detection (LOD). Furthermore 3a serves as unique luminescent probe for highly discriminative and quick responsive detection of three noxious oxo-anions (Cr2O7 (2-) CrO4 (2-) MnO4-) in water via noteworthy turn-off responses and extreme low LODs (Cr2O7 (2-) 0.9; CrO4 (2-) 0.29; MnO4- 0.25 ppm). It is imperative to stress the outstanding reusability of the MOF toward multicyclic sensing of all four major water contaminants alongside visible colorimetric changes upon individual analyte detection. Mechanistic insights in light of the electron transfer route together with density functional theory calculations portray the influence of pore functionalization in framework-analyte interactions including alternation in energy levels where varying degrees of contribution of energy transfer explicitly authenticates high quenching of the material.
Keywords: chemically robust cationic MOF; DFT calculation; fast responsive detection; humid CO2 capture; TNP and oxo-anion sensing

Dicationic liquid mediated synthesis of tetrazoloquinolinyl methoxy phenyl 4-thiazolidinones and their antibacterial and antitubercular evaluation - Deshmukh, A. R.; Dhumal, S. T.; Nawale, L. U.; Khedkar, V. M.; Sarkar, D.; Mane, R. A. (Synthetic Communications, 2019)
In a search of new potentially active antitubercular agents here we have synthesized 3-substituted phenyl-2-(4-(tetrazolo[1,5-a]quinolin-4-ylmethoxy)phenyl)thiazolidin-4-ones (8a–l) and evaluated their antibacterial, particularly antitubercular activity. These have been conveniently synthesized by performing one–pot cyclocondensation of 4-(tetrazolo[1,5-a]quinolin-4-ylmethoxy)benzaldehyde, anilines and mercaptoacetic acid in dicationic ionic liquid, (3-methyl-1-[3-(methyl-1H-imidazolium-1-yl)propyl]-1H-imidazolium dibromide [C3(MIM)2–2Br]) and obtained excellent yields of (8a–l). 4-Thiazolidinones (8a–l) were thoroughly characterized by their spectral analyses. These compounds have been screened for their in vitro antitubercular activity against Mycobacterium tuberculosis H37Ra and Mycobacterium bovis (BCG). The compounds 8a, 8c, and 8e exhibited notable in vitro antitubercular activity compare to the reference, Rifampicin. Molecular docking study has also been performed to know the binding mode of these analogs in to the active site of DprE1 enzyme. The synthesized compounds were also evaluated for their in vitro antibacterial activity and amongst them compound 8k has shown moderate activity against both gram-negative and gram-positive bacterial strains.

Direct thermal polymerization approach to N-rich holey carbon nitride nanosheets and their promising photocatalytic H-2 evolution and charge-storage activities - Antil, Bindu; Kumar, Lakshya; Reddy, K. P.; Gopinath, C. S.; Deka, Sasanka (ACS Sustainable Chemistry & Engineering, 2019)
Energy conversion and energy storage are two crucial challenges in green chemistry that have attracted tremendous attention for the last several decades. In this work, we have addressed both issues by synthesizing nitrogen-rich, few-layer-thick holey graphitic carbon nitride (g-C3N4) nanosheets by a simple, novel, direct thermal polymerization method, which is found to be very good in photocatalytic H-2 evolution reaction (energy-conversion) and charge-storage supercapacitor (energy-storage) applications. This as-synthesized conjugated polymer semiconductor (obtained stoichiometry C3N4.8) with unique structural and morphological advantages exhibits superior photocatalytic water splitting activity to H-2 evolution (2 620 mu mol h(-1) g(-1)) without the help of any cocatalysts under visible light in the presence of 20% triethanolamine (TEOA). The calculated apparent quantum yield is 8.5% at 427 nm, and the rate of photocatalytic hydrogen generation remained constant for nine consecutive catalytic cycles (9 h photocatalysis). The present material also shows electrochemical double layer capacitor (EDLC) behavior in alkaline electrolyte, where a symmetric coin cell device consisting of this electrode material without any large area support or conductive filler delivers high specific capacitance (275 F g(-1)), energy density (30 Wh kg(-1)), and power density (6651 W kg(-1)), and the supercapacitor cell can retain >98% capacitance efficiency up to 10 000 measured cycles at various current densities.
Keywords: g-C3N4; Hydrogen evolution; nanosheets; Photocatalyst; supercapacitor; water splitting

Distribution and bioprospecting potential of actinobacteria from Indian mangrove ecosystems - Manikkam, Radhakrishnan; Pati, Premalata; Thangavel, Shanmugasundaram; Venugopal, Gopikrishnan; Joseph, Jerrine; Ramasamy, Balagurunathan; Dastager, Syed G. (Microbial Diversity in Ecosystem Sustainability and Biotechnological Applications, 2019)
Actinobacteria are the ecologically and economically important prokaryotes with the unprecedented ability to produce novel metabolites. They are widely distributed in nature due to their physiological and metabolic versatility. Actinobacteria from marine ecosystem are recognized as a promising source for novel bioactive metabolites. Notably, mangroves are the most fertile and productive marine ecosystem due to their ecophysiological conditions and vast microbial diversity. At the global level, there are many novel actinobacteria which have been reported from mangrove ecosystems and also explored for their bioprospecting potential. However, in India, microbiologists have explored actinobacteria from selected mangrove ecosystems for the past five decades with special reference to culturable diversity and antimicrobial, antimycobacterial, anticancer, and enzymatic activities. So far, around 22 rare actinobacterial genera have been reported from the Indian mangrove ecosystems. However, several other novel actinobacteria with promising bioprospecting potential are yet to be explored. Hence, research on actinobacteria in the Indian mangrove ecosystem is still in its infancy. This chapter will describe the exploratory research work carried out on the importance, diversity, antimicrobial and enzymatic activity, biodegradation, and nanotechnological potency of actinobacteria from the Indian mangrove ecosystems. This chapter will enable researchers to identify the gaps to be bridged for further research on Indian mangrove actinobacteria and exploit their potential to the maximum benefit to mankind.

Draft genome sequence of freshwater-derived streptomyces sp. strain BPSDS2, isolated from damte stream, northeast India - Zothanpuia; Passari, Ajit Kumar; Deka, Vinay; Rajput, Lakshmi P. M.; Priya, Purbajyoti; Dharne, Mahesh; Dastager, Syed; Mathew, Oommen K.; Hashem, Abeer; Abd_ Allah, Elsayed Fathi; Singh, Bhim Pratap (American Society for Microbiology, 2019)
We report the draft genome sequence of Streptomyces sp. strain BPSDS2, isolated from freshwater sediments in Northeast India. The draft genome has a size of 8.27 Mb and 7,559 protein-coding sequences.

Efficient and cost effective synthesis of acetamides catalyzed by calcium chloride - Sangole, M. T.; Thorat, S. M.; Shirsath, S.; Deshmukh, S. P.; Muthukrishnan, M.; Mujahid, M. (Indian Journal of Chemistry Section B-Organic Chemistry Including Medicinal Chemistry, 2019)
CaCl2 has been found to be an efficient and cost effective catalyst for the rapid synthesis of acetamides in high yields. The use of stoichiometric quantities of acetic anhydride under solvent free conditions without any additional chromatographic purifications makes this protocol a safe alternative to the existing methods.
Keywords: Acetamide; acetylation; Acylation; Amine; CaCl2

Electrocatalysis of oxygen reduction reaction on shape-controlled pt and pd nanoparticles-importance of surface cleanliness and reconstruction - Devivaraprasad, Ruttala; Nalajala, Naresh; Bera, Bapi; Neergat, Manoj (Frontiers in Chemistry, 2019)
Shape-controlled precious metal nanoparticles have attracted significant research interest in the recent past due to their fundamental and scientific importance. Because of their crystallographic-orientation-dependent properties, these metal nanoparticles have tremendous implications in electrocatalysis. This review aims to discuss the strategies for synthesis of shape-controlled platinum (Pt) and palladium (Pd) nanoparticles and procedures for the surfactant removal, without compromising their surface structural integrity. In particular, the electrocatalysis of oxygen reduction reaction (ORR) on shape-controlled nanoparticles (Pt and Pd) is discussed and the results are analyzed in the context of that reported with single crystal electrodes. Accepted theories on the stability of precious metal nanoparticle surfaces under electrochemical conditions are revisited. Dissolution, reconstruction, and comprehensive views on the factors that contribute to the loss of electrochemically active surface area (ESA) of nanoparticles leading to an inevitable decrease in ORR activity are presented. The contribution of adsorbed electrolyte anions, in-situ generated adsorbates and contaminants toward the ESA reduction are also discussed. Methods for the revival of activity of surfaces contaminated with adsorbed impurities without perturbing the surface structure and its implications to electrocatalysis are reviewed.
Keywords: Adsorption; Dissolution; oxygen reduction reaction; Palladium; platinum; reconstruction; shape-control; surface cleaning

Electron crystallography - Blake, Alexander J.; de Boissieu, Marc; Nangia, Ashwini (IUCRJ, 2019)

Embedding S=1/2 Kagome-like lattice in reduced graphene oxide - Gupta, Kriti; Jha, Plawan Kumar; Dadwal, Arun; Debnath, Anil K.; Jaiswal, Ishan; Rana, Shammi; Joy, Pattayil A.; Ballav, Nirmalya (Journal of Physical Chemistry Letters, 2019)
An elegant platform to explore frustrated magnetism is the kagome spin lattice. In this work, clinoatacamite, a naturally occurring S = 1/2 kagome-like antiferromagnetic insulator, is synthesized in water at ambient pressure for the first time from a cuprous chloride (CuCl) precursor whereby Cu(I) was spontaneously oxidized to Cu(II) in the form of clinoatacamite [Cu-2(OH)(3)Cl] with a simultaneous reduction of graphene oxide (GO) to reduced graphene oxide (rGO) in one pot. A stable nanocomposite of phase-pure clinoatacamite nanocrystals embedded in the rGO matrix was isolated. The clinoatacamite-rGO nanocomposite was determined to be magnetically active with a markedly enhanced coercive field of similar to 2500 Oe at S K as well as electronically active with a conductivity value of similar to 200 S.m(-1) at 300 K. Our results illustrate an avenue of combining exotic magnetic and electronic lattices without impeding their individual characteristics and synergistically generating a new class of magnetic semiconductors.

Enhancing epi-cedrol production in escherichia coli by fusion expression of farnesyl pyrophosphate synthase and epi-cedrol synthase - Navale, Govinda R; Sharma, Poojadevi; Said, Madhukar S; Ramkumar, Sudha; Dharne, Mahesh S; Thulasiram, H., V; Shinde, Sandip S (Engineering in Life Science, 2019)
Terpene synthase catalyses acyclic diphosphate farnesyl diphosphate into desired sesquiterpenes. In this study, a fusion enzyme was constructed by linking Santalum album farnesyl pyrophosphate synthase (SaFPPS) individually with terpene synthase and Artemisia annua Epi-cedrol synthase (AaECS). The stop codon at the N-terminus of SaFPPS was removed and replaced by a short peptide (GSGGS) to introduce a linker between the two open reading frames. This fusion clone was expressed in Escherichia coli Rosseta DE3 cells. The fusion enzyme FPPS-ECS produced sesquiterpene 8-epi-cedrol from substrates isopentenyl pyrophosphate and dimethylallyl pyrophosphate through sequential reactions. The K-m values for FPPS-ECS for isopentyl diphosphate was 4.71 mu M. The fusion enzyme carried out the efficient conversion of IPP to epi-cedrol, in comparison to single enzymes SaFPPS and AaECS when combined together in enzyme assay over time. Further, the recombinant E. coli BL21 strain harbouring fusion plasmid successfully produced epi-cedrol in fermentation medium. The strain having fusion plasmid (pET32a-FPPS-ECS) produced 1.084 +/- 0.09 mg/L epi-cedrol, while the strain harbouring mixed plasmid (pRSETB-FPPS and pET28a-ECS) showed 1.002 +/- 0.07 mg/L titre in fermentation medium by overexpression and MEP pathway utilization. Structural analysis was done by I-TASSER server and docking was done by AutoDock Vina software, which suggested that secondary structure of the N- C terminal domain and their relative positions to functional domains of the fusion enzyme was greatly significant to the catalytic properties of the fusion enzymatic complex than individual enzymes.

Estrogen receptor activation in response to Azadirachtin A stimulates osteoblast differentiation and bone formation in mice - Kushwaha, Priyanka; Ahmad, Naseer; Dhar, V. Yogeshwar; Verma, Ashwni; Haldar, Saikat; Mulani, Fayaj A.; Trivedi, Prabodh K.; Mishra, Prabhat R.; Thulasiram, V. Hirekodathakallu; Trivedi, Ritu (Journal of Cellular Physiology, 2019)
The positive effectsof the sex hormone in sustaining bone homeostasis areexercised by maintaining the equilibrium betweencell activity and apoptosis. In this regard, the importance of estrogen receptors in maintaining the bone is that it is anattractive drug target,if devoid of known side effects. In this study, we show that a natural pure compound Azadirachtin A (Aza A) isolated from Azadirachta indica binds selectively to a site in the estrogen receptor, identifying itself to bea selective tissue modifier. Using computational and medicinal chemistry, we show that Aza A binds potentially and selectively to estrogen receptor-alpha (ER alpha) as compared with ER beta. This preferential binding of Aza A to ER alpha with good pharmacokinetic distribution in the body forms metabolites, showing that it is well absorbed. In in vivo estrogen deficiency models for osteoporosis, Aza A at a much lower dose enhances new bone formation at both sites of the trabecular and cortical bone with increased bone strength and presentswith no hyperplastic effect in the uterus.
Keywords: ALP; Gene expression; micro-CT; mineralization; osteoblast cells

Experimental investigation on performance of helical spring lock washer under different operating conditions - Wagh, Hemant Krishnarao; Desale, Girish R. (Journal of Failure Analysis and Prevention, 2019)
In mechanical systems, emphasis has been given to the selection and health monitoring of both bolt and nut in the bolted joint assembly; less attention has been given to the performance of spring washers due to tightening torque, usage duration and reuse. In the present experimental investigation, the load–deflection characteristics of helical spring lock (HSL) washer during compressive loading and unloading are determined using newly designed and developed test rig. Also, the load–deflection characteristics of the HSL washers are examined for reuse cycles. Additionally, the effect of compressive loading and unloading on the reaction load within elastic limit is determined. Further, the loss of helix height due to compressive loading and its effect on strain energy is examined. The tests have evidenced of loss of helix height and strain energy of HSL washer due to compressive loading which deteriorates its functionality in further usage.

Fine-tuning of Terahertz resonances in hydrogen-bonded organic molecular complexes - Dash, Jyotirmayee; Ray, Shaumik; Devi, Nirmala; Basutkar, Nitin; Ambade, Ashootosh V.; Pesala, Bala (Journal of Molecular Structure, 2019)
Novel organic molecular complexes have been designed and synthesized to obtain prominent Terahertz (THz) resonances in the low-frequency region. Intermolecular hydrogen bonds give rise to low-frequency THz resonances and hence binary organic molecular complexes of pyridyl alkylamide/benzamide (DAP) and hexyl thymine (C6THY) with multiple strong intermolecular hydrogen bonds (N-H–-O and N-H–-N) are designed and synthesized. THz resonances of the complexes are fine-tuned by varying the number of benzene rings in the DAP moiety (PrDAP + C6THY, PrPhDAP + C6THY and PhDAP + C6THY). DFT simulation studies of two molecule clusters have been carried out to understand the origin of low-frequency THz resonances. It has been observed that the lowest THz resonances (< 2 THz) originate due to translation/rotation of the whole crystal structure and the resonances from 2 to 4 THz are mainly due to intermolecular hydrogen bond bending/stretching vibrations. In order to understand the individual hydrogen bond strengths, compliance constants, which are inverse of the force constants are calculated and Natural Bond Orbital (NBO) analysis has been carried out. Comparison of the experimental THz spectra of different complexes shows that there is a small but tunable variation in THz resonances from one complex to another. Tuning of THz resonances has potential applications in designing THz tags, which can be used in various anti-counterfeiting applications such as currency notes, pharmaceutical tablets. (C) 2019 Elsevier B.V. All rights reserved.
Keywords: Compliance constant; Natural bond orbital analysis; Organic molecular complex; Terahertz spectroscopy

Flower bud proteome reveals modulation of sex-biased proteins potentially associated with sex expression and modification in dioecious Coccinia grandis - Devani, Ravi Suresh; Chirmade, Tejas; Sinha, Sangram; Bendahmane, Abdelhafid; Dholakia, Bhushan B.; Banerjee, Anjan Kumar; Banerjee, Jayeeta (BMC Plant Biology, 2019)
BackgroundDioecy is an important sexual system wherein, male and female flowers are borne on separate unisexual plants. Knowledge of sex-related differences can enhance our understanding in molecular and developmental processes leading to unisexual flower development. Coccinia grandis is a dioecious species belonging to Cucurbitaceae, a family well-known for diverse sexual forms. Male and female plants have 22A+XY and 22A+XX chromosomes, respectively. Previously, we have reported a gynomonoecious form (22A+XX) of C. grandis bearing morphologically hermaphrodite flowers (GyM-H) and female flowers (GyM-F). Also, we have showed that foliar spray of AgNO3 on female plant induces morphologically hermaphrodite bud development (Ag-H) despite the absence of Y-chromosome.ResultsTo identify sex-related differences, total proteomes from male, female, GyM-H and Ag-H flower buds at early and middle stages of development were analysed by label-free proteomics. Protein search against the cucumber protein sequences (Phytozome) as well as in silico translated C. grandis flower bud transcriptome database, resulted in the identification of 2426 and 3385 proteins (FDR <= 1%), respectively. The latter database was chosen for further analysis as it led to the detection of higher number of proteins. Identified proteins were annotated using BLAST2GO pipeline. SWATH-MS-based comparative abundance analysis between Female_Early_vs_Male_Early, Ag_Early_vs_Female_Early, GyM-H_Middle_vs_Male_Middle and Ag_Middle_vs_ Male_Middle led to the identification of 650, 1108, 905 and 805 differentially expressed proteins, respectively, at fold change >= 1.5 and P <= 0.05. Ethylene biosynthesis-related candidates as highlighted in protein interaction network were upregulated in female buds compared to male buds. AgNO3 treatment on female plant induced proteins related to pollen development in Ag-H buds. Additionally, a few proteins governing pollen germination and tube growth were highly enriched in male buds compared to Ag-H and GyM-H buds.ConclusionOverall, current proteomic analysis provides insights in the identification of key proteins governing dioecy and unisexual flower development in cucurbitaceae, the second largest horticultural family in terms of economic importance. Also, our results suggest that the ethylene-mediated stamen inhibition might be conserved in dioecious C. grandis similar to its monoecious cucurbit relatives. Further, male-biased proteins associated with pollen germination and tube growth identified here can help in understanding pollen fertility.
Keywords: Coccinia grandis; Dioecy; Pollen fertility; proteomics; Sex modification; Stamen arrest

Fluorogenic BODIPY molecular rotor as an apoptosis marker - Ashokkumar, Pichandi; Ashoka, Anila Hoskere; Collot, Mayeul; Das, Amitava; Klymchenko, Andrey S. (Chemical Communications, 2019)
Based on a BODIPY molecular rotor and a zinc-dipicolylamine receptor, we designed a fluorogenic probe for the detection of apoptosis. Being poorly emissive in solution and with healthy cells, it selectively binds phosphatidylserine of early apoptotic cells and internalizes into late apoptotic cells, lighting up its green fluorescence.

Formic-acid-induced using recyclable-ionic liquids as catalysts for lignin conversion into aromatic co-products - Singh, Sandip K.; Dhepe, Paresh L. (Waste and Biomass Valorization, 2019)
Lignin has been widely named as a sustainable and renewable bioresource of energy, fuels, chemicals and materials, particularly phenolic chemicals production on Earth. These bio-derived compounds are in great potential need of biorefinery to valorize complete plant biomass. Lignin depolymerization showed a great promise approach to convert into low molecular aromatic products. In this report, high molecular weight (54,000 Da) lignin depolymerization into maximum yields (87%), (>= 95 +/- 6% mass balance) using a formic acid along with dual (-SO3H) functionalized imidazole-based recyclable (4 times) Bronsted acidic ionic liquids (BAILs) as catalysts have been investigated in H2O-CH3OH (1:5, v/v) at 120 degrees C for 1 h. The structural correlations between the lignin and aromatic products were studied by bulk (CHNS, GPC, etc.) and molecular (UV-Vis, FT-IR, NMR (1D/2D) levels experimental techniques. Additionally, the identification of aromatic products was carried out by applying HPLC, GC and GC-MS techniques. Graphic Addition of a formic acid into Bronsted acidic ionic liquids improved the catalytic efficiency significantly for lignin depolymerization into 87% low molecular weight aromatic products. [GRAPHICS] .
Keywords: Bulk and molecular levels analysis; depolymerization; Dual functionalized ionic liquids; Formic acid; lignin

Friction-mediated flow and jamming in a two-dimensional silo with two exit orifices - Orpe, Ashish V.; Doshi, Pankaj (Physical Review E, 2019)
We show that the interparticle friction coefficient significantly influences the flow and jamming behavior of granular materials exiting through the orifice of a two-dimensional silo in the presence of another orifice located in its vicinity. The fluctuations emanating from a continuous flow through a larger orifice results in an intermittent flow through the smaller orifice consisting of sequential jamming and flowing events. The mean time duration of jammed and flow events, respectively, increase and decrease monotonically with increasing interparticle friction coefficient. The frequency of unjamming instances (n(u)), however, shows a nonmonotonic behavior comprising an increase followed by a decrease with increasing friction coefficient. The decrease on either side of the maximum, then, represents a system moving progressively towards a permanently jammed or a permanently flowing state. The overall behavior shows a systematic dependence on the interorifice distance, which determines the strength of the fluctuations reaching the smaller orifice leading to unjamming instances. The probability distributions of jamming and flowing times are nearly similar for different combinations of friction coefficients and interorifice distances studied and, respectively, exhibit exponential and power-law tails.

Glycerol acetylation considering competing dimerization - Soares, Andre V. -H.; Kale, Sumeet S.; Armbruster, Udo; Passos, Fabio B.; Umbarkar, Shubhangi B.; Dongare, Mohan K.; Martin, Andreas (International Journal of Chemical Kinetics, 2019)
Glycerol acetylation is a very interesting reaction for studies of consecutive kinetics. In this short communication, we present a pseudo-homogeneous model for the synthesis of triacetyl glycerol from the reaction of glycerol and acetic acid over strongly acidic Amberlyst-15 and Amberlyst-70 catalysts, considering a dimerization of diacetyl glycerol (DAG) into diglycerol tetraacetate as a parallel reaction and compare the results with a model without side reactions. The best fits were obtained for apparent zeroth-order dimerization and first-order consecutive reactions in the presence of acetic acid in excess and with removal of water. An adaptation was made for DAG. The proposed model shows that the formation of DAG is faster than the consumption of glycerol, which could be an explanation for the occurrence of DAG dimerization instead of other parallel reactions in acetylation.
Keywords: apparent kinetics; diacetyl glycerol dimerization; glycerol acetylation

Hierarchical K/LTL zeolite as solid base for aqueous phase hydrogenation of xylose to xylitol - Tangale N. P.; Niphadkar, P. S.; Joshi, P. N.; Dhepe, P. L. (Microporous and Mesoporous Materials, 2019)
Post-synthesis modification by alkali treatment was employed for the synthesis of hierarchical K/LTL zeolites with varying degree of mesoporosity. For the alkali treatment, the concentration of aqueous KOH solution was changed from 0.3 to 2.8 M keeping the quantity per gram of zeolite fixed. The influence of the alkali concentration on the chemical composition, powder XRD crystallinity, morphology, basicity, and the textural properties of resultant hierarchical zeolites was investigated. Variation in the concentration of KOH solution was found to control the degree of preferential desilication with the preserved structural fingerprint of K/LTL zeolite. As a result, the generation of mesoporosity was observed along with 1) the decrease in the Si/Al ratio and percentage relative crystallinity, and 2) an increase in BET surface area and mesopore volume. 27Al MAS-NMR results showed that all the aluminum atoms present in the tetrahedral coordination after alkali treatment, which provides an elegant approach for significantly increasing the basic sites in the hierarchical zeolites. As a heterogeneous catalyst, the hierarchical K/LTL zeolites demonstrated the improved performance in the hydrogenation of xylose to xylitol as compared to the parent K/LTL zeolite. The different process parameters were assessed in order to maximize the hydrogenation activity. Among all the hierarchical zeolites, the enhanced catalytic activity was shown by the hierarchical K/LTL prepared by using 1.5 M KOH solution when it is used along with the 3.5 wt% platinum loaded γ-Al2O3 catalyst. This optimum activity may be attributed to the higher surface area, accessible basic sites, nano-sized Pt on γ-Al2O3, and the development of substantial intracrystalline mesoporosity for the enhanced molecular diffusion of reactant to and from the hierarchical zeolite with better-preserved crystallinity.

High-energy flexible supercapacitor-synergistic effects of polyhydroquinone and RuO2 center dot xH(2)O with microsized, few-layered, self-supportive exfoliated-graphite sheets - Muniraj, Vedi Kuyil Azhagan; Dwivedi, Pravin Kumari; Tamhane, Parikshit Shivaji; Szunerits, Sabine; Boukherroub, Rabah; Shelke, Manjusha Vilas (ACS Applied Materials & Interfaces, 2019)
An effective and straightforward route for tailoring the self-supporting, exfoliated flexible graphite substrate (E-FGS) using electrochemical anodization is proposed. E-FGS has essential features of highly exfoliated, few-layered, two-dimensional graphite sheets with the size of several tens of micrometers, interconnected along the axis of the substrate surface. The novel hierarchical porous structural morphology of E-FGS enables large active sites for efficient electrolyte ion and charge transport when used as electrode material for a supercapacitor. In order to effectively utilize this promising E-FGS electrode for energy storage purpose, a ternary composite is further synthesized with pseudocapacitive polyhydroquinone (PHQ) and hydrous RuO2 (hRO). hRO is synthesized via a sol-gel route, while electropolymerization is utilized for the electrodeposition of PHQ over E-FGS. Ultimately, the fabricated self-supporting E-FGS-based flexible supercapacitor is capable of delivering areal specific capacitance values as high as 378 mF cm(-2) at a current density of 1 mA cm(-2). Addition of the pseudocapacitive component to the E-FGS texture leads to similar to 10 times increase of the electrochemical charge storage capability. The imposition of mechanical forces to this flexible supercapacitor device results in trivial changes in electrochemical properties and is still capable of retaining 91% of the initial specific capacitance after 10 000 cycles. Alongside, the fabricated symmetrical solid-state flexible device exhibited a high energy density of 8.4 mu Wh cm(-2). The excellent performance along with the ease of synthesis and fabrication process of the flexible solid-state supercapacitor device using PHQ/hRO/E-FGS holds promise for large-scale production.
Keywords: graphite exfoliation; polyhydroquinone; ruthenium oxide; solid-state flexible supercapacitor; Ternary Composite

Highly efficient Pt-MoOx/ZrO2 catalyst for green diesel production - Janampelli, Sagar; Darbha, Srinivas (Catalysis Communications, 2019)
Bimetallic Pt-MoOx supported on ZrO2 exhibits higher catalytic activity than known catalysts for converting fatty acids into green diesel at as low as 200 degrees C. A change in selectivity from decarboxylation/decarbonylation to hydrodeoxygenation and enhancement in the deoxygenation activity of Pt were observed when MoOx was also present in the catalyst composition. In X-ray photoelectron spectra, Pt 4f lines of 4Pt-8MoO(x)/ZrO2 occurred at lower binding energies than those for 4Pt/ZrO2. Part of Mo was reduced from +6 to +5 oxidation state in the presence of Pt. There seems to exist some electronic interaction between the support and metal, making 4Pt-8MoO(x)/ZrO2 a highly efficient and selective deoxygenation catalyst.
Keywords: Bimetallic catalyst; Biofuel; Deoxygenation of fatty acids; Green Diesel; Hydrocarbons; Supported platinum catalyst

Highly efficient rhodium-phosphite catalyzed hydroformylation of camphene and other terpenes - Pagar, N. S.; Deshpande, R. M. (Asian Journal of Chemistry, 2019)

Hydrocarbon chain-length dependence of solvation dynamics in alcohol-based deep eutectic solvents: a two-dimensional infrared spectroscopic investigation - Chatterjee, Srijan; Ghosh, Deborin; Haldar, Tapas; Deb, Pranab; Sakpal, Sushil S.; Deshmukh, Samadhan H.; Kashid, Somnath M.; Bagchi, Sayan (Journal of Physical Chemistry B, 2019)
Deep eutectic solvents (DESs) have gained popularity in recent years as an environmentally benign, inexpensive alternative to organic solvents for diverse applications in chemistry and biology. Among them, alcohol-based DESs serve as useful media in various applications due to their significantly low viscosity as compared to other DESs. Despite their importance as media, little is known how their solvation dynamics change as a function of the hydrocarbon chain length of the alcohol constituent. In order to obtain insights into the chain-length dependence of the solvation dynamics, we have performed two-dimensional infrared spectroscopy on three alcohol-based DESs by systematically varying the hydrocarbon chain length. The results reveal that the solvent dynamics slows down monotonically with an increase in the chain length. This increase in the dynamic timescales also shows a strong correlation with the concomitant increase in the viscosity of DESs. In addition, we have performed molecular dynamics simulations to compare with the experimental results, thereby testing the capacity of simulations to determine the amplitudes and timescales of the structural fluctuations on fast timescales under thermal equilibrium conditions.

Hydrodeoxygenation of vegetable oils and fatty acids over different group VIII metal catalysts for producing biofuels - Janampelli, Sagar; Darbha, Srinivas (Catalysis Surveys From Asia, 2019)
Energy security and environment protection are two important aspects of sustainable development. Biofuels are renewable and carbon neutral. They are suitable replacement for conventional fossil derived transport fuels. Their use leads to sustainable development. Among several technological options, catalytic hydrodeoxygenation of vegetable oils leading to diesel-range hydrocarbons is the most attractive approach for producing biofuels. The green diesel, thus produced, could be blended with petro-diesel or used as standalone fuel in the conventional diesel engines. Our research group has been active in developing efficient solid catalysts for hydroprocessing of vegetable oils. This account presents some of our efforts using supported group VIII metals and the importance of electronic contact between metal and support on the catalytic activity and hydrodeoxygenation selectivity in hydroprocessing of vegetable oils.
Keywords: biofuels; Catalysis over group VIII metals; Deoxygenation; Hydroprocessing; Renewable diesel

Hydrogen bond assisted photoinduced intramolecular electron transfer and proton coupled electron transfer in an ultrafast time domain using a ruthenium-anthraquinone dyad - Dey, Ananta; Dana, Jayanta; Aute, Sunil; Das, Amitava; Ghosh, Hirendra N. (Photochemical & Photobiological Sciences, 2019)
Quinones play a significant role as primary electron acceptors in the natural photosynthetic system of photosystem II, and their reduction is known to be facilitated by hydrogen-bond donors or protonation. In this study, a ruthenium(ii) polypyridyl complex 1 coupled to an anthraquinone (AQ) functionality through a rigid imidazole (Im) spacer has been synthesized to examine the effect of H-bonding on both the thermal and photoinduced electron transfer reactions. The anthraquinone moiety of complex 1 is fused to a benzi-imidazole system bearing C & xe001;(OMIDLINE)-M-AQ HORIZONTAL ELLIPSISHNIm based H-bonding at one side of the anthraquinone moiety so that intramolecular hydrogen bonding from the imidazole group to the nearby quinone carbonyl can occur. The hydrogen bond formation involving the semiquinone radical anion produced through the photoinduced reduction process in Ru-im-AQ and the imidazole proton in complex 1 resulted in a significant positive shift of one electron reduction potential of complex 1. The kinetics for the formation of the charge-separated states was explored by using femtosecond transient absorption spectroscopy. Hydrogen bonding between water and the reduced anthraquinone accounted for thermodynamic and kinetic stabilization of these charge-separated states. An attempt has been made to assess the relative importance of the driving force and solvent polarity, in the rates of photoinduced electron transfer in complex 1. The 490 nm transient absorption band of anthraquinone radical anions (AQ(-)) and a broad absorption in the 580-750 nm region having maxima at similar to 690 nm have been observed and this is attributed to the generation of a transient Ru3+-species of the corresponding complex 1. Addition of water entails an acceleration of electron transfer rates by a factor of 3.33. The system investigated may serve as a model for the mechanistic diversity of PCET reactions in general with water as a primary proton donor. Furthermore, our studies are relevant for understanding proton-coupled electron transfer (PCET) reactivity of electronically excited states at a fundamental level because changes in hydrogen-bonding strength accompanying changes in redox states may be regarded as a variant form of PCET.

Hydrophobic WO3/SiO2 catalyst for the nitration of aromatics in liquid phase - Kulal, A. B.; Kasabe, M. M.; Jadhav, P. V.; Dongare, M. K.; Umbarkar, S. B. (Applied Catalysis A-General, 2019)
WO3/SiO2 solid acid catalyst synthesized using sol gel method has shown promising activity (up to 65% conversion) for aromatic nitration in liquid phase using commercial nitric acid (70%) as nitrating agent without using any sulfuric acid. The water formed during the reaction as well as water from dilute nitric acid (70%) was removed azeotropically, however due to the hydrophilic nature of the catalyst, some water gets strongly adsorbed on catalyst surface forming a barrier layer between catalyst and organics. This prevents effective adsorption of substrate on catalyst surface for its subsequent reaction. To improve the activity further, the hydrophilic/hydrophobic nature of the catalyst was altered by post modification by grafting with commercial short chain organosilane (Dynasylan 9896). The modified 20% WO3/SiO2 catalyst when used for o-xylene nitration in liquid phase, showed significant increase in the conversion from 65% to 80% under identical reaction conditions. Catalyst characterization revealed decrease in the surface area of 20% WO3/SiO2 from 356 m(2)/g to 302 m(2)/g after grafting with Dynasylan 9896. The fine dispersion of WO3 particles (2-5 run) on silica support was not affected due to modification. NMR and FTIR study revealed the decrease in surface hydroxyl groups imparting hydrophobicity to the catalyst. Interestingly the total acidic sites of the catalyst remained almost unaltered (0.54 mmol NH3/g) even after modification. Even though, the acidity and other characteristics of the catalyst did not change appreciably, there was a considerable increase in the o-xylene conversion which can be ascribed to the hydrophobic nature of the catalyst.
Keywords: Aromatic nitration; grafting; heterogeneous catalysis; Hydrophobic; Sol-gel synthesis

Inducing disorder in order: hierarchically porous covalent organic framework nanostructures for rapid removal of persistent organic pollutants - Karak, Suvendu; Dey, Kaushik; Torris, Arun; Halder, Arjun; Bera, Saibal; Kanheerampockil, Fayis; Banerjee, Rahul (Journal of the American Chemical Society, 2019)
The key factor responsible for fast diffusion and mass transfer through a porous material is the availability of a widely open pore interior having complete accessibility from their surface. However, because of their highly stacked nature, ordered two-dimensional (2D) materials fail to find real-world applicability, as it is difficult to take advantage of their complete structure, especially the inner cores. In this regard, three-dimensional (3D) nanostructures constructed from layered two-dimensional crystallites could prove to be advantageous. However, the real challenge is to cultivate a porous nanostructure with ordered pores where the pores are surrounded by crystalline walls. Herein, a simple yet versatile in situ gas-phase foaming technique has been employed to address these cardinal issues. The use of baking soda leads to the continuous effervescence of CO2 during the crystallization of foam, which creates ripples and fluctuations on the surface of the 2D crystallites. The induction of ordered micropores within the disordered 3D architecture synergistically renders fast diffusion of various guests through the interconnected pore network. The high-density defects in the hierarchically porous structure help in ultrafast adsorption (<10 s) of various pollutants (removal efficiency of 99%) from water, all of which would lead to significant environmental benefit. The pseudo-second-order rate constant for the BPA pollutant is 182.3 g mg(-1) min(-1), which is the highest among all the literature reports to date. The high removal efficiency (highest efficiency of 94% and average efficiency of 70%) of a persistent organic pollutant has been attended for the first time.

Insights into the origin of life: did it begin from HCN and H2O? - Das, Tamal; Ghule, Siddharth; Vanka, Kumar (Acs Central Science, 2019)
The seminal Urey-Miller experiments showed that molecules crucial to life such as HCN could have formed in the reducing atmosphere of the Hadean Earth and then dissolved in the oceans. Subsequent proponents of the "RNA World" hypothesis have shown aqueous HCN to be the starting point for the formation of the precursors of RNA and proteins. However, the conditions of early Earth suggest that aqueous HCN would have had to react under a significant number of constraints. Therefore, given the limiting conditions, could RNA and protein precursors still have formed from aqueous HCN? If so, what mechanistic routes would have been followed? The current computational study, with the aid of the ab initio nanoreactor (AINR), a powerful new tool in computational chemistry, addresses these crucial questions. Gratifyingly, not only do the results from the AINR approach show that aqueous HCN could indeed have been the source of RNA and protein precursors, but they also indicate that just the interaction of HCN with water would have sufficed to begin a series of reactions leading to the precursors. The current work therefore provides important missing links in the story of prebiotic chemistry and charts the road from aqueous HCN to the precursors of RNA and proteins.

In-situ generated Mn3O4-reduced graphene oxide nanocomposite for oxygen reduction reaction and isolated reduced graphene oxide for supercapacitor applications - Jha, Plawan Kumar; Kashyap, Varchaswal; Gupta, Kriti; Kumar, Vikash; Debnath, Anil Krishna; Roy, Debashree; Rana, Shammi; Kurungot, Sreekumar; Ballav, Nirmalya (Carbon, 2019)
We have generated in situ nanocomposite of Mn3O4 and reduced graphene oxide (rGO) upon employing wet-chemical reduction of graphene oxide (GO) by Mn(II) salt as mild-reducing agent for the first time and examined the oxygen reduction reaction (ORR) activity in 0.1 M KOH electrolyte. The half-wave potential (E-1/2) of the nanocomposite catalyst (20% Mn3O4-rGO/C) was found to be around -0.153 V which is only similar to 87 mV negative from the commercially available catalyst (20% Pt/C). Remarkably, after 5000 linear sweep voltammetry cycles the E-1/2 shifted marginally by 20 mV; and the number of electrons transferred during ORR was estimated to be close to 4. Such an efficient electrocatalytic performance of the nanocomposite was primarily attributed to the synergistic interaction between Mn3O4 and rGO. The fabricated all-solid-state supercapacitor of rGO (extracted from the nanocomposite) in aqueous polyvinyl alcohol-sulfuric acid (PVA-H2SO4) gel polymer electrolyte (GPE) showed C-s value of similar to 310 F/g at a current density of 1 A/g along with long durability (10,000 charge-discharge cycles). All-solid-state flexible rGO supercapacitor exhibited high-flexibility and excellent durability (30,000 cycles with 100% retention of C-s). Our results provide an enormous opportunity in designing transition metal oxides decorated semiconducting reduced graphene oxide nanocomposite platforms for various electrochemical applications. (C) 2019 Elsevier Ltd. All rights reserved.

Kinetics of hydroformylation of 1-decene using carbon-supported ossified HRh(CO)(TPPTS)(3) catalyst - Pagar, Nitin S.; Deshpande, Raj M. (International Journal of Chemical Kinetics, 2019)
The kinetics of hydroformylation of 1-decene has been investigated using a carbon-supported ossified HRh(CO)(TPPTS)(3)/Ba catalyst in a temperature range of 343-363 K. The effect of concentration of 1-decene, catalyst loading, partial pressure of H-2 and CO, and stirring speed on the reaction rate has been investigated. A first-order dependence was observed for catalyst concentration and hydrogen partial pressure. The rate showed a typical case of substrate inhibition for high 1-decene concentration. The rate varied with a linear dependence on P-CO up to a CO partial pressure of 5-6 MPa in contrast to the general trends; for most of the rhodium-phosphine catalyzed hydroformylation reactions, severe inhibition of rate is observed with an increase in CO pressure. A rate equation has been proposed, which was found to be in good agreement with the observed rate data within the limit of experimental errors. The kinetic parameters and activation energy values have been reported.
Keywords: 1-decene; Hydroformylation; kinetics; ossification; supported ossified

Ligand-enabled gold-catalyzed C(sp(2))-n cross-coupling reactions of aryl iodides with amines - Akram, Manjur O.; Das, Avishek; Chakrabarty, Indradweep; Patil, Nitin T. (Organic Letters, 2019)
The first example of ancillary (P,N)-ligand-enabled gold-catalyzed C-N cross-coupling reactions of aryl iodides with amines is reported. The high generality of the reaction in de novo synthesis, late-stage modifications, and cascade processes to access functionalized indolinones and carbazoles underscores the synthetic potential of the presented strategy. Monitoring the reaction with ESI-HRMS and NMR provided strong evidence for the in situ formation of putative high valent Au(III) intermediates.

Light-triggered, spatially localized chemistry by photoinduced electron transfer - Usgaonkar, S.; Deshmukh, S.; Biswas, B.; Karjule, N.; Yadav, P.; Nithyanandhan, J.; Kumaraswamy, G. (Angewandte Chemie-International Edition, 2019)
It is of immense interest to exert spatial and temporal control of chemical reactions. It is now demonstrated that irradiation can trigger reactions specifically at the surface of a simple colloidal construct, obtained by adsorbing polyethyleneimine on fluorescent colloidal particles. Exciting the fluorescent dye in the colloid affords photoinduced electron transfer to spatially proximal amine groups on the adsorbed polymer to form free radical ions. It is demonstrated that these can be harnessed to polymerize acrylic acid monomer at the particle surface, or to break up colloidal assemblies by cleaving a cross‐linked polymer mesh. Formation of free radical ions is not a function of the size of the colloid, neither is it restricted to a specific fluorophore. Fluorophores with redox potentials that allow photoinduced electron transfer with amine groups show formation of free radical ions.

Lignin conversion using catalytic ionic liquids: understanding the role of cations, anions, and hammett acidity functions - Singh, Sandip K.; Dhepe, Paresh L. (Industrial & Engineering Chemistry Research, 2019)
Because it is undisputable that lignin depolymerization is a must to make the biorefinery concept economically feasible, several efforts are put toward it; however, a lot of catalyst designing is required to achieve efficient depolymerization activities. In this work, we show a systematic approach in the synthesis and characterization of ionic liquids (ILs) with varying combinations of cations (imidazole, benzimidazole, phosphonium, and ammonium) and anions (HSO4, PTS (p-toluenesulfonate), Cl, H2PO4, SnCl3, FeCl4, and CuCl3) for the depolymerization of lignin into low-molecular weight aromatic fractions (<220 g/mol) under mild reaction conditions (120 degrees C, 1 h, ambient pressure). In a methodical approach, effects of various reaction parameters such as temperature (70-170 degrees C), time (15-360 min), pressure (N-2, 0.5-3 MPa), solvents and substrate, and so forth were studied to achieve best activity. Among all the catalysts, IL with the imidazolium cation and HSO4 as the anion showed best activity (78% yield). Subsequent to depolymerization, three aromatic monomers (5 wt % pure vanillin) were isolated using flash column chromatography. These aromatic monomers were characterized using gas chromatography (GC), GC-mass spectrometry, and NMR techniques for their purity. Hammett acidity functions (H-0) of ILs were measured using UV-vis photo-spectroscopy, and values are correlated with lignin depolymerization results. Lignin and tetrahydrofuran-soluble products were thoroughly characterized using assorted physicochemical techniques such as NMR (H-1 and C-13), gel permittivity chromatography, thermogravimetric analysis, and so forth. The catalyst was recycled up to six runs and showed similar results in consecutive reactions.

Lithium compounds as single site catalysts for hydroboration of alkenes and alkynes - Bisai, Milan Kumar; Yadav, Sandeep; Das, Tamal; Vanka, Kumar; Sen, Sakya S. (Chemical Communications, 2019)
The hydroboration of alkenes and alkynes using easily accessible lithium compounds [2,6-di-tert-butyl phenolatelithium (1a) and 1,1 ` dilithioferrocene (1b)] has been achieved with good yields, high functional group tolerance and excellent chemoselectivity. Deuterium-labeling experiments confirm the cis-addition of pinacolborane. The methodology has been further extended to myrcene, which undergoes selective 4,3-hydroboration. DFT calculations provide insights into the mechanism.

Metabolomic dynamics reveals oxidative stress in spongy tissue disorder during ripening of mangifera indica l. fruit - Oak, Pranjali; Deshpande, Ashish; Giri, Ashok; Gupta, Vidya (Metabolites, 2019)
Spongy tissue disorder, a mesocarp specific malady, severely affects the flavor and pulp characters of Alphonso mango fruit reducing its consumer acceptability. Here, we investigated comparative metabolomic changes that occur during ripening in healthy and spongy tissue-affected fruits using high resolution mass spectrometric analysis. During the spongy tissue formation, 46 metabolites were identified to be differentially accumulated. These putative metabolites belong to various primary and secondary metabolic pathways potentially involved in maintaining the quality of the fruit. Analysis revealed metabolic variations in tricarboxylic acid cycle and gamma amino butyric acid shunt generating reactive oxygen species, which causes stressed conditions inside the mesocarp. Further, reduced levels of antioxidants and enzymes dissipating reactive oxygen species in mesocarp deteriorate the fruit physiology. This oxidative stress all along affects the level of amino acids, sugars and enzymes responsible for flavor generation in the fruit. Our results provide metabolic insights into spongy tissue development in ripening Alphonso mango fruit.
Keywords: gamma amino butyric acid shunt; mango metabolomics; Oxidative stress; spongy tissue disorder; tricarboxylic acid cycle

Metagenomic insights to understand transient influence of Yamuna River on taxonomic and functional aspects of bacterial and archaeal communities of River Ganges - Samson, Rachel; Shah, Manan; Yadav, Rakeshkumar; Sarode, Priyanka; Rajput, Vinay; Dastager, Syed G.; Dharne, Mahesh S.; Khairnar, Krishna (Science of the Total Environment, 2019)
River confluences are interesting ecosystems to investigate for their microbial community structure and functional potentials. River Ganges is one of the most important and holy river of India with great mythological history and religious significance. The Yamuna River meets Ganges at the Prayagraj (formerly known as Allahabad), India to form a unique confluence. The influence of Yamuna River on taxonomic and functional aspects of microbiome at this confluence and its downstream, remains unexplored. To unveil this dearth, whole metagenome sequencing of the microbial (bacterial and archaeal) community from the sediment samples of December 2017 sampling expedition was executed using high throughput MinION technology. Results revealed differences in the relative abundance of bacterial and archaeal communities across the confluence. Grouped by the confluence, a higher abundance of Proteobacteria and lower abundance of Bacteroidetes and Firnacutes was observed for Yamuna River (G15Y) and at immediate downstream of confluence of Ganges (G15DS), as compared to the upstream, confluence, and farther downstream of confluence. A similar trend was observed for archaeal communities with a higher abundance of Euryarchaeoto in G15Y and G15DS, indicating Yamuna River's influence. Functional gene(s) analysis revealed the influence of Yamuna River on xenobiotic degradation, resistance to toxic compounds, and antibiotic resistance interceded by the autochthonous microbes at the confluence and succeeding downstream locations. Overall, similar taxonomic and functional profiles of microbial communities before confluence (upstream of Ganges) and farther downstream of confluence, suggested a transient influence of Yamuna River. Our study is significant since it may be foundational basis to understand impact of Yamuna River and also rare event of mass bathing on the microbiome of River Ganges. Further investigation would be required to understand, the underlying cause behind the restoration of microbial profiles post-confluence farther zone, to unravel the rejuvenation aspects of this unique ecosystem. (C) 2019 Elsevier B.A. All rights reserved.
Keywords: Confluence zone; Ganges; Metagenomics; Transient influence; Yamuna

Methodology of evaluating sustainability index of a biomass processing enterprise: a case study of native cow dung-urine biorefinery - Joglekar, Saurabh N.; Darwai, Vivek; Mandavgane, Sachin A.; Kulkarni, Bhaskar D. (Environmental Science and Pollution Research, 2019)
Agriculture and its allied sector contribute significantly to the gross domestic product of every country. Several small-scale enterprises engaged in waste biomass processing have been setup recently. Such industrial setups not only help in solving the waste management issues but also play an important role in offering employment at the grass root level generating a significant social impact along with economic advantage to the local entrepreneur. Hence, assessment of such biomass processing enterprise (BPE) based on economic, environment, and social parameters has become necessary. In this paper, a general framework for sustainability assessment is discussed using a case study of cow dung-urine biorefinery as a representative BPE. Real-time data of BPE has been collected for evaluation and a sustainability index (SI) is evaluated using multicriteria decision method. The SI is calculated as per the weightage assigned and value function of the indicator and criteria. The SI for the BPE was observed to be 0.69 for the chosen set of criteria and indicator and weightages. A sensitivity analysis has been performed to check the dependence of the results on the weightages assigned to various criteria and indicators. It was also observed that the results were more sensitive to the indicators having a low value function.
Keywords: Indicator analysis; MIVES; Multicriteria decision analysis; Performance evaluation; Sustainability assessment framework

Microbacterium enclense sp. nov., isolated from sediment sample (vol 65, pg 2064, 2015) - Mawlankar, Rahul R.; Mual, Poonam; Sonalkar, Vidya V.; Thorat, Meghana N.; Verma, Ashish; Srinivasan, Krishnamurthi; Dastager, Syed G. (International Journal of Systematic and Evolutionary Microbiology, 2019)

Microglial priming of antigen presentation and adaptive stimulation in Alzheimer's disease - Das, Rashmi; Chinnathambi, Subashchandrabose (Cellular and Molecular Life Sciences, 2019)
The prominent pathological consequences of Alzheimer's disease (AD) are the misfolding and mis-sorting of two cellular proteins, amyloid-beta and microtubule-associated protein Tau. The accumulation of toxic phosphorylated Tau inside the neurons induces the increased processing of amyloid-beta-associated signaling cascade and vice versa. Neuroinflammation-driven synaptic depletion and cognitive decline are substantiated by the cross talk of activated microglia and astroglia, leading to neuron degeneration. Microglia are the brain-resident immune effectors that prove their diverse functions in maintaining CNS homeostasis via collaboration with astrocytes and T lymphocytes. Age-related senescence and chronic inflammation activate microglia with increased pro-inflammatory markers, oxidative damage and phagocytosis. But the improper processing of misfolded protein via lysosomal pathway destines the spreading of 'seed' constituents to the nearby healthy neurons. Primed microglia process and present self-antigen such as amyloid-beta and modified Tau to the infiltrated T lymphocytes through MHC I/II molecules. After an effective conversation with CD4(+) T cells, microglial phenotype can be altered from pro-active M1 to neuro-protective M2 type, which corresponds to the tissue remodeling and homeostasis. In this review, we are focusing on the change in functionality of microglia from innate to adaptive immune response in the context of neuroprotection, which may help in the search of novel immune therapy in AD.

Molecular and dissociative adsorption of oxygen on au-pd bimetallic clusters: role of composition and spin state of the cluster - Dar, Manzoor Ahmad; Krishnamurty, Sailaja (Acs Omega, 2019)
Utilization of molecular oxygen as an oxidizing agent in industrially important reactions is the ultimate goal to design environmentally benign processes under ambient conditions. However, the high thermal stability and a large O-O dissociation barrier in O-2 molecule pose a great challenge toward its successful application in the oxidative chemistry. To achieve this goal, different catalysts based on monometallic and bimetallic clusters have been developed over the years to promote binding and dissociation of molecular oxygen. The successful design of efficient metal cluster catalysis needs an in-depth knowledge of synergistic effects between different metal atoms and intrinsic catalytic mechanisms for O-2 adsorption and dissociation. Here, we present a systematic theoretical investigation of reaction pathways for O-2 adsorption and dissociation on Au-8, Pd-8, and Au8-nPdn (n = 1-7) nanoclusters in different spin states. The density functional calculations point out that the O-2 dissociation barriers can be significantly reduced with the help of certain bimetallic clusters along specific spin channels. Our results particularly indicate that Au5Pd3 and Au1Pd7 show very large O-2 binding energies of 1.76 and 1.69 eV, respectively. The enhanced O-2 binding subsequently leads to low activation barriers of 0.98 and 1.19 eV along the doublet and quartet spin channels, respectively, without the involvement of any spin flip-over for O-2 dissociation. Furthermore, the computed O-2 dissociation barriers are significantly low as compared to the already reported barriers (1.95-3.65 eV) on monometallic and bimetallic Au-Ag clusters. The results provide key mechanistic insights into the interaction and dissociation of molecular oxygen with Au-Pd clusters, which can prove informative for the design of efficient catalysts for oxidative chemistry involving molecular oxygen as a reactant.

Molecular dynamics study on growth of carbon dioxide and methane hydrate from a seed crystal - Nakate, Prajakta; Ghosh, Bappa; Das, Subhadip; Roy, Sudip; Kumar, Rajnish (Chinese Journal of Chemical Engineering, 2019)
In the current work, molecular dynamics simulation is employed to understand the intrinsic growth of carbon dioxide and methane hydrate starting from a seed crystal of methane and carbon dioxide respectively. This comparison was carried out because it has relevance to the recovery of methane gas from natural gas hydrate reservoirs by simultaneously sequestering a greenhouse gas like CO2. The seed crystal of carbon dioxide and methane hydrate was allowed to grow from a super-saturated mixture of carbon dioxide or methane molecules in water respectively. Two different concentrations (1:6 and 1:8.5) of CO2/CH4 molecules per water molecule were chosen based on gas-water composition in hydrate phase. The molecular level growth as a function of time was investigated by all atomistic molecular dynamics simulation under suitable temperature and pressure range which was well above the hydrate stability zone to ensure significantly faster growth kinetics. The concentration of CO2 molecules in water played a significant role in growth kinetics, and it was observed that maximizing the CO2 concentration in the aqueous phase may not result in faster growth of CO2 hydrate. On the contrary, methane hydrate growth was independent of methane molecule concentration in the aqueous phase. We have validated our results by performing experimental work on carbon dioxide hydrate where it was seen that under conditions appropriate for liquid CO2, the growth for carbon dioxide hydrate was very slow in the beginning. (C) 2019 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.
Keywords: Cage dynamics; CH4 recovery; CO2 sequestration; F-4 order parameter; kinetics; Natural gas hydrate; Thermodynamics

Molecular studies of NAD- and NADP-glutamate dehydrogenases decipher the conundrum of yeast-hypha dimorphism in zygomycete Benjaminiella poitrasii - Pathan, Ejaj K.; Ghormade, Vandana; Panwar, Sneh Lata; Prasad, Rajendra; Deshpande, Mukund V. (Fems Yeast Research, 2019)
Benjaminiella poitrasii, a zygomycete, shows glucose- and temperature-dependent yeast (Y)-hypha (H) dimorphic transition. Earlier, we reported the biochemical correlation of relative proportion of NAD- and NADP-glutamate dehydrogenases (GDHs) with Y-H transition. Further, we observed the presence of one NAD-GDH and two form-specific NADP-GDH isoenzymes in B. poitrasii. However, molecular studies are necessary to elucidate the explicit role of GDHs in regulating Y-H reversible transition. Here, we report the isolation and characterization of one NAD (BpNADGDH, 2.643 kb) and two separate genes, BpNADPGDH I (Y-form specific, 1.365 kb) and BpNADPGDH II (H-form specific, 1.368 kb) coding for NADP-GDH isoenzymes in B. poitrasii. The transcriptional profiling during Y-H transition showed higher BpNADPGDH I expression in Y cells while expression of BpNADPGDH II was higher in H cells. Moreover, the yeast-form monomorphic mutant (Y-5) did not show BpNADPGDH II expression under normal dimorphism triggering conditions. Transformation with H-form specific BpNADPGDH II induced the germ tube formation in Y-5, which confirmed the cause-effect relationship between BpNADPGDH genes and morphological outcome in B. poitrasii. Interestingly, expression of H-form specific BpNADPGDH II also induced germ tube formation in human pathogenic, non-dimorphic yeast Candida glabrata, which further corroborated our findings.
Keywords: Benjaminiella poitrasii; Candida glabrata; differential gene expression; dimorphism; monomorphic mutant; NAD/NADP-glutamate dehydrogenase; yeast-hypha transition

Molybdenum carbide catalyst for the reduction of CO2 to CO: surface science aspects by NAPPES and catalysis studies - Reddy, Kasala Prabhakar; Dama, Srikanth; Mhamane, Nitin B.; Ghosalya, Manoj K.; Raja, Thirumalaiswamy; Satyanarayana, Chilukuri V.; Gopinath, Chinnakonda S. (Dalton Transactions, 2019)
Carbon dioxide is a greenhouse gas, and needs to be converted into one of the useful feedstocks, such as carbon monoxide and methanol. We demonstrate the reduction of CO2 with H-2 as a reducing agent, via a reverse water gas shift (RWGS) reaction, by using a potential and low cost Mo2C catalyst. Mo2C was evaluated for CO2 hydrogenation at ambient pressure as a function of temperature, and CO2 : H-2 ratio at a gas hourly space velocity (GHSV) of 20 000 h(-1). It is demonstrated that the Mo2C catalyst with 1 : 3 ratio of CO2 : H-2 is highly active (58% CO2 conversion) and selective (62%) towards CO at 723 K at ambient pressure. Both properties (basicity and redox properties) and high catalytic activity observed with Mo2C around 700 K correlate well and indicate a strong synergy among them towards CO2 activation. X-ray diffraction and Raman analysis show that the Mo2C catalyst remains in the beta-Mo2C form before and after the reaction. The mechanistic aspects of the RWGS reaction were determined by near-ambient pressure X-ray photoelectron spectroscopy (NAPXPS) with in situ generated Mo2C from carburization of Mo-metal foil. NAPXPS measurements were carried out at near ambient pressure (0.1 mbar) and various temperatures. Throughout the reaction, no significant changes in the Mo2+ oxidation state (of Mo2C) were observed indicating that the catalyst is highly stable; C and O 1s spectral results indicate the oxycarbide species as an active intermediate for RWGS. A good correlation is observed between catalytic activity from atmospheric pressure reactors and the electronic structure details derived from NAPXPS results, which establishes the structure-activity correlation.

Nanobiopesticide perspectives for protection and nutrition of plants - Deshpande, Mukund V. (Nano-Biopesticides Today and Future Perspectives, 2019)
Presently, the actual utilization of pesticides on the target is < 0.1% due to spray drift, rainwater leaching, etc., which makes pesticide usage inefficient. Therefore, in the agriculture scenario, the use of nanobiopesticides for ease of application, targeted delivery and a reduction in the load of pesticides, and protection of microbial diversity is holding significant promise. The nanomaterials in sensors and biosensors help in miniaturization, the real-time measurement of more variables present in low quantities, and early detection of pests and pathogens. The metal and metal oxide nanoparticles play significant roles in biopesticide degradation. However, one has to address issues related to associated risks to crop health, soil microbial diversity, and mankind due to such nano-based products. Accordingly, formulation of regulatory guidelines for their use also becomes an important component of the strategy.

Neural anti-inflammatory natural product periconianone A: total synthesis and biological evaluation - Kalmode, Hanuman P.; Patil, Suhag S.; Handore, Kishor L.; Athawale, Paresh R.; Dandela, Rambabu; Verma, Abhishek Kumar; Basu, Anirban; Reddy, D. Srinivasa (European Journal of Organic Chemistry, 2019)
Total synthesis of periconianone A, an eremophilane-type sesquiterpenoid with impressive neural anti-inflammatory potential, has been accomplished. Diels-Alder/aldol strategy to construct tetrahydro-naphthalene-2,6-dione scaffold, allylic oxidation of dienone using DBU/O-2 and postulated biomimetic aldol reaction to construct 6/6/6 tricyclic system are the highlights of the present synthesis. Furthermore, the synthesized (+/-)-periconianone A and two close analogs were tested for their neural anti-inflammatory activity using various assays. In the course of our study we found a structurally simplified analog is superior to (+/-)-periconianone A.
Keywords: Aldol; Allylic oxidation; Biological evaluation; Cytotoxicity; Diels-Alder; Periconianone A

Neutral imino-methyl benzenesulfonate-ligated Pd(II) complexes and implications in ethylene polymerization - Deshmukh, Satej S.; Gaikwad, Shahaji R.; Mote, Nilesh R.; Manod, M.; Gonnade, Rajesh G.; Chikkali, Samir H. (ACS Omega, 2019)
A reaction between sodium 2-formylbenzenesulfonate and aniline revealed the near-quantitative (91%) formation of sodium-2-((phenylimino)methyl)benzenesulfonate L1. The identity of L1 was unambiguously ascertained using spectroscopic and analytical methods. The scope of this methodology was widened and various electron-donating amines were treated with sodium 2-formylbenzenesulfonate, and a small library of 6 imine ligands L2-L6 was generated. When L2 was treated with [(COD)PdMeCI], instead of the anticipated [L2PdMe(DMSO)] complex, the formation of [(DMSO)(2)Pd2Cl2Me2] Pd Dim was observed. Nevertheless, the desired imino-methyl benzenesulfonate-ligated palladium complex [L2PdMe(Lu)] C1 was obtained by in situ abstraction of chloride and addition of bulky 2,6-lutidine as the donor group. The observation of characteristic Pd-Me protons at 0.06 ppm and the corresponding carbon at -8.1 ppm indicated the formation of C1. These 1D NMR observations were corroborated by 2D C-H correlation spectra and mass analysis, and the existence of C1 was unambiguously ascertained. Along the same lines, L4 and L5 were treated with a palladium precursor to produce [L4/SPdMe(Lu)]-type complexes C2-C3 in 55-84% yield, and their identity was established by using a combination of spectroscopic tools, analytical methods, and single-crystal X-ray diffraction. The synthetic utility of C1-C3 has been demonstrated by utilizing these complexes in the insertion polymerization of ethylene to polyethylene.

N-Heterocyclic carbene-catalyzed umpolung of imines for the enantioselective synthesis of dihydroquinoxalines - Das, Tamal Kanti; Ghosh, Avik; Balanna, Kuruva; Behera, Pradipta; Gonnade, Rajesh G.; Marelli, Udaya Kiran; Das, Abhijit Kumar; Biju, Akkattu T. (ACS Catalysis, 2019)
N-heterocyclic carbene (NHC) organocatalysis is widely employed for the umpolung of aldehydes and recently to the umpolung of Michael acceptors and aldimines. Described herein is the NHC-organocatalyzed umpolung of aldimines for the enantioselective synthesis of nitrogen heterocycles. The bisimines generated from the condensation of 1,2-phenylenediamines and salicylaldehydes undergo intramolecular cyclization in the presence of a chiral NHC catalyst, resulting in the formation of dihydroquinoxalines in moderate to good yields and er values. Detailed DFT studies shed light on the role of -OH groups in stabilizing the initially generated aza-Breslow intermediates via intramolecular hydrogen bonds. Preliminary photophysical studies on the synthesized dihydroquinoxalines revealed that these molecules can be used for the sensing of various acids and bases.
Keywords: dihydroquinoxalines; imines; N-heterocyclic carbenes; organocatalysis; umpolung

Nickel(ii)-catalyzed direct olefination of benzyl alcohols with sulfones with the liberation of H-2 - Landge, Vinod G.; Yadav, Vinita; Subaramanian, Murugan; Dangarh, Pragya; Balaraman, Ekambaram (Chemical Communications, 2019)
A nickel(II)-catalyzed direct olefination of benzyl alcohols with sulfones to access various terminal and internal olefins with the liberation of hydrogen gas is reported.

Novel fatty alkene from marine bacteria: a thermo stable biosurfactant and its applications - Ram, Hari; Sahu, Amit Kumar; Said, Madhukar S.; Banpurkar, Arun G.; Gajbhiye, Jayant M.; Dastager, Syed G. (Journal of Hazardous Materials, 2019)
In this study, a novel thermo stable biosurfactants, 1-Pentanonacontene (C95H190) a fatty alkene and 3-Hydroxy16-methylheptadecanoic acid (C18H36O3) were isolated from a marine isolate SGD-AC-13. Biosurfactants were produced using 1% yeast extract in tap water as production medium at 24 h in flask and 12 h in bioreactor. Using 16S rRNA gene sequence (1515 bp) and BCL card (bioMerieux VITEK (R)), strain was identified as Bacillus sp. Crude biosurfactant reduced the surface tension of distilled water to 31.32 +/- 0.93 mN/m with CMC value of 0.3 mg/ml. Cell free supernatant showed excellent emulsification and oil displacement activity with stability up to 160 degrees C, pH 6-12 and 50 g/L NaCl conc. Biosurfactants were characterized using FTIR, TLC, HPLC LC-MS and NMR spectroscopy. Cell free supernatant reduced the contact angle of distilled water droplet from 117 degrees to 52.28 degrees and of 2% pesticide from 78.77 degrees to 73.42 degrees while 750 mu g/ml of crude biosurfactant reduced from 66.06 degrees to 56.33 degrees for 2% pesticide and recovered 35% ULO and 12% HWCO from the contaminated sand. To our best of knowledge, this is the first report of thermo stable fatty alkene as a biosurfactant and is structurally different from previously reported, with having potential application in agriculture, oil recovery and bioremediation.
Keywords: Bioremediation; Biosurfactants; Fatty alkene; Thermo stability; Wettability

Novel synthetic approach for designing metal-free, redox-active quinoxaline-benzimidazole-based organic polymers with high energy storage capacity - Salunkhe, Pravin S.; Patil, Yuvraj S.; Dhole, Indrajeet A.; Kalshetti, Basavraj S.; Patil, Vikas B.; Mane, Shivshankar R.; Ghanwat, Anil A. (New Journal of Chemistry, 2019)
New organic framework materials, namely, polyphenylquinoxaline (QOP) and polyphenylquinoxaline-benzimidazole (QOP-BOP) were designed using a high-temperature (>100 degrees C) polymerization reaction with different monomers, i.e., 2,5-bis-[(4-benzoylcarbonyl)phenyl]-3-4 diphenyl thiophene (BbcPDT), aromatic tetraamines and biphenyl dicarboxylic acid. The QOP-BOP copolymer exhibited specific capacitance (SC) of 305 F g(-1) at the current density of 2 A g(-1) and 88% retention of its initial specific capacitance after 1000 cycles, which resulted in good cyclic stability. This work establishes the first use of thiophene integrated with quinoxaline-benzimidazole units for energy storage applications and provides strategies for further developments in the performance of such conjugated materials. Cyclic voltammetry, charge-discharge and electrochemical impedance techniques were used to evaluate the electrochemical parameters, which demonstrated their potential in future energy storage devices.

One-pot Au [III]-/lewis acid catalyzed cycloisomerization of nitroalkynes and [3+3]cycloaddition with donor-acceptor cyclopropanes - Dhote, Pawan S.; Ramana, V. Chepuri (Organic Letters, 2019)
A one-pot protocol for the synthesis of a tricyclic pseudoindoxyl scaffold from 2-nitroalkynylbenzenes, comprising of an Au(III)-catalyzed nitroalkyne cycloisomerization leading to isatogen and its [3 + 3]-cycloaddition with donor-acceptor cyclopropanes mediated by a suitable Lewis acid, has been developed.

Paintable room-temperature phosphorescent liquid formulations of alkylated bromonaphthalimide - Goudappagouda; Manthanath, A.; Wakchaure, V. C.; Ranjeesh, K. C.; Das, T.; Vanka, K.; Nakanishi, T.; Babu, S. S. (Angewandte Chemie - International Edition, 2019)
Organic phosphors have been widely explored with an understanding that crystalline molecular ordering is a requisite for enhanced intersystem crossing. In this context, we explored the room‐temperature phosphorescence features of a solvent‐free organic liquid phosphor in air. While alkyl chain substitution varied the physical states of the bromonaphthalimides, the phosphorescence remained unaltered for the solvent‐free liquid in air. As the first report, a solvent‐free liquid of a long swallow‐tailed bromonaphthalimide exhibits room‐temperature phosphorescence in air. Doping of the phosphor with carbonyl guests resulted in enhanced phosphorescence, and hence a large‐area paintable phosphorescent liquid composite with improved lifetime and quantum yield was developed.

Palladium impregnated amine Co-condensed hexagonal mesoporous silica: a novel catalyst in tailoring suzuki and heck coupling reactions in base free condition - Das, Prangya Paramita; Prabhakaran, Vinod C.; Nanda, Samik; Sen, Debasis; Chowdhury, Biswajit (ChemistrySelect, 2019)
Palladium impregnated amine co-condensed hexagonal mesoporous silicas (HMS-X) were synthesized (sol-gel process) using different amines (Ethylene diamine and pyridine) of various concentrations (0.25 equiv. and 2 equiv.). The effect of amine concentration on the local structure of hexagonal mesoporous silica was studied. The catalyst shows excellent catalytic activity and high TOF towards both Suzuki and Heck coupling reactions without using any base in reaction medium with the solvent DMF:water in (1:1) ratio. The catalyst was reused and it was recyclable up to three cycle without any appreciable loss of activity and the kinetics of the reaction varying different parameters also have been studied thoroughly.
Keywords: Amine functionalized silica; Base free; Heck reaction; Palladium supported catalysts; Suzuki reaction

Pathways to defense metabolites and evading fruit bitterness in genus Solanum evolved through 2-oxoglutarate-dependent dioxygenases - Cardenas, Pablo D.; Sonawane, Prashant D.; Heinig, Uwe; Jozwiak, Adam; Panda, Sayantan; Abebie, Bekele; Kazachkova, Yana; Pliner, Margarita; Unger, Tamar; Wolf, Dalia; Ofner, Itai; Vilaprinyo, Ester; et al. (Nature Communications, 2019)
The genus Solanum comprises three food crops (potato, tomato, and eggplant), which are consumed on daily basis worldwide and also producers of notorious anti-nutritional steroidal glycoalkaloids (SGAs). Hydroxylated SGAs (i.e. leptinines) serve as precursors for leptines that act as defenses against Colorado Potato Beetle (Leptinotarsa decemlineata Say), an important pest of potato worldwide. However, SGA hydroxylating enzymes remain unknown. Here, we discover that 2-OXOGLUTARATE-DEPENDENT-DIOXYGENASE (2-ODD) enzymes catalyze SGA-hydroxylation across various Solanum species. In contrast to cultivated potato, Solanum chacoense, a widespread wild potato species, has evolved a 2-ODD enzyme leading to the formation of leptinines. Furthermore, we find a related 2-ODD in tomato that catalyzes the hydroxylation of the bitter a-tomatine to hydroxytomatine, the first committed step in the chemical shift towards downstream ripening-associated non-bitter SGAs (e.g. esculeoside A). This 2-ODD enzyme prevents bitterness in ripe tomato fruit consumed today which otherwise would remain unpleasant in taste and more toxic.

Phosphite-Catalyzed C-H allylation of azaarenes via an enantioselective [2,3]-Aza-wittig rearrangement - Motaleb, Abdul; Rani, Soniya; Das, Tamal; Gonnade, Rajesh G.; Maity, Pradip (Angewandte Chemie-International Edition, 2019)
A phosphite-mediated [2,3]-aza-Wittig rearrangement has been developed for the regio- and enantioselective allylic alkylation of six-membered heteroaromatic compounds (azaarenes). The nucleophilic phosphite adducts of N-allyl salts undergo a stereoselective base-mediated aza-Wittig rearrangement and dissociation of the chiral phosphite for overall C-H functionalization of azaarenes. This method provides efficient access to tertiary and quaternary chiral centers in isoquinoline, quinoline, and pyridine systems, tolerating a broad variety of substituents on both the allyl part and azaarenes. Catalysis with chiral phosphites is also demonstrated with synthetically useful yields and enantioselectivities.

Photoexcited toluidine blue inhibits tau aggregation in Alzheimer's disease - Dubey, Tushar; Nalini, Gorantla Vijay; Chandrashekara, Kagepura Thammaiah; Chinnathambi, Subashchandrabose (Acs Omega, 2019)
The aggregates of microtubule-associated protein Tau are considered as a major hallmark of Alzheimer's disease. Tau aggregates accumulate intracellularly leading to neuronal toxicity. Numerous approaches have been targeted against Tau protein aggregation, which include application of synthetic and natural compounds. Toluidine blue is a basic dye of phenothiazine family, which on irradiation with a 630 nm light gets converted into a photoexcited form, leading to generation of singlet oxygen species. Methylene blue is the parent compound of toluidine blue, which has been reported to be potent against tauopathy. In the present work, we studied the potency of toluidine blue and photoexcited toluidine blue against Tau aggregation. Biochemical and biophysical analyses using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, ThS fluorescence, circular dichroism spectroscopy, and electron microscopy suggested that toluidine blue inhibited the aggregation of Tau in vitro. The photoexcited toluidine blue potentially dissolved the matured Tau fibrils, which indicated the disaggregation property of toluidine blue. The cell biology studies including the cytotoxicity assay and reactive oxygen species (ROS) production assay suggested toluidine blue to be a biocompatible dye as it reduced ROS levels and cell death. The photoexcited toluidine blue modulates the cytoskeleton network in cells, which was supported by immunofluorescence studies of neuronal cells. The studies in a UAS Tau E14 transgenic Drosophila model suggested that photoexcited toluidine blue was potent to restore the survival and memory deficits of Drosophila. The overall finding of our studies suggested toluidine blue to be a potent molecule in rescuing the Tau-mediated pathology by inhibiting its aggregation, reducing the cell death, and modulating the tubulin levels and behavioral characteristics of Drosophila. Thus, toluidine blue can be addressed as a potent molecule against Alzheimer's disease.

pH-responsive “supra-amphiphilic” nanoparticles based on homoarginine polypeptides - Praveen, Korra; Das, Soumen; Dhaware, Vinita; Pandey, Bhawana; Mondal, Basudeb; Sengupta, Sayam (ACS Applied Bio Materials, 2019)
pH-responsive “supra-amphiphiles” based on double hydrophilic, positively charged block copolypeptides such as PEG-b-poly-l-lysine together with low molecular weight stimuli-sensitive partners that contain phosphate and carboxylate groups have been widely studied. In contrast, the other widely used cationic polypeptide poly-l-arginine whose cell-penetrating properties are well-known has been much less explored for the synthesis of supra-amphiphile-based nanomaterials. It is also known that the guanidine side chain of arginine binds to carboxylate anions with binding constants that are 2.5 times higher than the corresponding amines of poly-l-lysine. Here, we demonstrate the fabrication of pH-sensitive supra-amphiphilic nanoparticles by simple mixing of PEG2k-b-poly(homoarginine) block copolymer and carboxylic acid containing functional low molecular weight organic compounds. A high yielding three-step methodology was developed for the synthesis of ε-N,N′-di-Boc-l-homoarginine-α-N-carboxyanhydride which was polymerized using amine-terminated PEG (2000 MW) to yield 100% guanine-functionalized polypeptide (PEG2k-b-PHR30) with controlled molecular weights and low PDIs. Incubation of PEG2k-b-PHR30 with four different carboxylic acids (including dexamethasone a glucocorticoid receptor used in cancer therapy) in water leads to the formation of “supra-amphiphilic” nanoparticles (<200 nm size) due to the charge neutralization resulting from the strong interaction between the guanidine group and the carboxylate group. All these nanoparticles were able to encapsulate the hydrophobic dye Nile red with varying efficiency. Although these assemblies were stable at neutral pH, upon lowering the pH of the solution between 4 and 5, the protonation of the carboxylic acids leads to disassembly of these nanoparticles. The cytotoxicity of all four “supra-amphiphilic” nanoparticles varied depending on the carboxylic acid used for their fabrication. While the nanoparticle formed using dioctylbenzoic acid displayed 80% cell viability at concentration of 60 μg/mL, those formed with the steroid deoxycholic acid or dexamethasone showed only 40% cell viability at similar concentrations. Colocalization studies performed using epifluorescence microscopy demonstrate the successful uptake of intact dye-encapsulated nanoparticle inside the cell.

Porosity switching in polymorphic porous organic cages with exceptional chemical stability - Bera, Saibal; Dey, Kaushik; Pal, Tapan K.; Halder, Arjun; Tothadi, Srinu; Karak, Suvendu; Addicoat, Matthew; Banerjee, Rahul (Angewandte Chemie-International Edition, 2019)
Porous solids that can be switched between different forms with distinct physical properties are appealing candidates for separation, catalysis, and host-guest chemistry. In this regard, porous organic cages (POCs) are of profound interest because of their solution-state accessibility. However, the application of POCs is limited by poor chemical stability. Synthesis of an exceptionally stable imine-linked (4+6) porous organic cage (TpOMe-CDA) is reported using 2,4,6-trimethoxy-1,3,5-triformyl benzene (TpOMe) as a precursor aldehyde. Introduction of the -OMe functional group to the aldehyde creates significant steric and hydrophobic characteristics in the environment around the imine bonds that protects the cage molecules from hydrolysis in the presence of acids or bases. The electronic effect of the -OMe group also plays an important role in enhancing the stability of the reported POCs. As a consequence, TpOMe-CDA reveals exceptional chemical stability in neutral, acidic and basic conditions, even in 12m NaOH. Interestingly, TpOMe-CDA exists in three different porous and non-porous polymorphic forms (, , and ) with respect to differences in crystallographic packing and the orientation of the flexible methoxy groups. All of the polymorphs retain their crystallinity even after treatment with acids and bases. All the polymorphs of TpOMe-CDA differ significantly in their properties as well as morphology and could be reversibly switched in the presence of an external stimulus.
Keywords: chemical stability; Morphology; organic cages; polymorphism; porosity switching

Preparation and activity of copper-gallium nanocomposite catalysts for carbon dioxide hydrogenation to methanol - Hengne, Amol M.; Yuan, Ding Jier; Date, Nandan S.; Saih, Youssef; Kamble, Sanjay P.; Rode, V. Chandrashekhar; Huang, Kuo-Wei (Industrial & Engineering Chemistry Research, 2019)
Copper (Cu) nanocomposite catalysts with gallium (Ga) and aluminum (Al) were prepared using the simultaneous coprecipitation digestion method. The catalysts were characterized by N-2 adsorption, N2O titration, XRD (X-ray diffraction), H-2-TPR (H-2 temperature-programmed reduction), XPS (X-ray photoelectron spectroscopy), and CO2-TPD (CO2 temperature-programmed desorption) techniques, and CO2 hydrogenation to methanol synthesis was performed. The use of Ga in Cu catalysts enhanced the weak basic sites more than the Cu catalysts with Al. With the CuGa nanocomposite formation, the catalyst showed a sequential reduction of CuO, for example, Cu+2 to Cu+ to Cu-0, and the Cu surface area was also high in comparison with CuAl. These findings confirmed that both the Cu surface area and CuO reducibility in the catalyst helped to boost the conversion of CO2, whereas selectivity to methanol was associated with the basicity of the catalyst. CuAl catalysts showed very poor selectivity to methanol despite CO formation, which could be due to the weak interaction of the CuAl nanocomposite catalysts compared to the CuGa nanocomposite catalysts.

Promising visible-light driven hydrogen production from water on a highly efficient CuCo2S4 nanosheet photocatalyst - Chauhan, Meenakshi; Soni, Kiran; Karthik, P. E.; Reddy, Kasala Prabhakar; Gopinath, Chinnakonda S.; Deka, Sasanka (Journal of Materials Chemistry A, 2019)
Here we report the development of CuCo2S4 nanosheets (NSs) as a promising semiconductor photocatalyst for the first time for water splitting reactions under visible light ( 420 nm) conditions, without the support of any noble metal co-catalyst. These NSs were produced via a simple hydrothermal route and have desirable properties with a band gap of 2.24 eV, and are photo-catalytically active under visible light with an apparent quantum yield (AQY) of 2.48%. Under visible light, CuCo2S4 NSs exhibit excellent weight-normalized photoactivity that generates approximate to 25900 mol h(-1) H-2 for 1 g of material with sulphide + sulphite as the sacrificial agent under 7.68 mW cm(-2) illumination, which is the best evolution reported for any chalcogenide semiconductor material without any co-catalyst to date with unprecedented long-term operational stability (up to 12 h study time). The rate and number of hydrogen gas molecules produced are 8.2855 x 10(15) s(-1) cm(-2) which remained constant for three catalytic cycles with a turnover frequency (TOF) value of 0.017 s(-1). The effect of Cu substitution on photoactivity was also investigated for comparative studies and it was found that CuCo2S4 NSs show superior activity to Cu0.5Co2.5S4 and Co3S4. These CuCo2S4 NSs absorb the entire visible range of the spectrum from 420 to 800 nm, and have a highly populated density of states at the Fermi level and a high donor concentration of 7.22 x 10(18) cm(-3) which have been evaluated by Mott-Schottky analysis and favourable adsorption of H+ on S-sites and conversion to H-2 corroborate their efficient photocatalytic activity.

Puzzle of highly virulent Metarhizium anisopliae strains from Annona squamosa fields against Helicoverpa armigera - Pathan, Ejaj K.; Deshpande, Mukund V. (Journal of Basic Microbiology, 2019)
In our search for indigenous virulent strains of the entomopathogenic fungi, we observed that Metarhizium isolates from soils associated with Annona squamosa (custard apple) have higher virulence (>90% mortality of Helicoverpa armigera larvae at 1/10(th) spore concentration) than strains isolated from Solanum lycopersicum (tomato) fields. Proteomic analysis revealed two insecticidal cyclopeptides of A. squamosa origin in the M. anisopliae strains that led to higher virulence against H. armigera. Transcriptomic and genomic data indicated that M. anisopliae strains and A. squamosa had more than 20 genes in common, including those for cyclic hexapeptide synthase, non-ribosomal peptide synthetase, and plant cyclotide genes, which are involved in the biosynthesis of insecticidal cyclopeptides. These genes were absent in M. anisopliae strains isolated from the S. lycopersicum fields. Further, these strains can establish an endophytic relationship with A. squamosa suggesting that these rhizospheric strains originally could be endophytes, which were eventually released into the soil. Further, Metarhizium strains associated with Capsicum annuum (chili), Azadirachta indica (neem), and Carica papaya (papaya) - plants with insecticidal properties - also had higher virulence against H. armigera. Thus exploration of rhizospheres of plants producing insecticidal metabolites to isolate entomopathogenic fungi, per se, could be a viable strategy in agricultural for crop protection.
Keywords: Annona squamosa; Biocontrol; endophyte; entomopathogen; Helicoverpa armigera; horizontal gene transfer; insecticidal peptides; Metarhizium; natural transformation

Rapid and greener method for utilization of plaster of paris (POP) waste generated from biomedical samples - Navale, G.R.; Gohil, K.N.; Puppala, K.R.; Shinde, S.S.; Umbarkar, S.; Dharne, M.S. (International Journal of Environmental Science and Technology, 2019)
Plaster of Paris (POP) is one of the recalcitrant wastes generated from dentistry and orthopaedic materials used in healthcare sector. The current practice of disposal of POP waste-harbouring biomedical material by incineration is very critical and environmentally unfriendly. The eco-friendly and rapid disintegration of such biomedical-related POP waste was done by treating with ammonium bicarbonate solution (20% w/v ABC) to form non-hazardous products like ammonium sulphate and calcium carbonate in the form of sludge. The ammonium sulphate (NH4)2SO4 is generally used in agriculture as a chemical fertilizer and calcium carbonate (CaCO3) as an additive in construction sector making this process cost-effective and value addition. Interestingly, 20% ABC solution also had significant antibiofilm, antimicrobial activity against fungi, yeast and bacterial strains probably due to its high pH-driven osmotic effect. Therefore, 20% ABC solution finds dual eco-friendly application in disinfection of used POP, especially arising from biomedical waste from patients.
Keywords: Biomedical waste; Eco-friendly disintegration; Plaster of Paris waste

Remarkably distinct mechanical flexibility in three structurally similar semiconducting organic crystals studied by nanoindentation and molecular dynamics - Devarapalli, Ramesh; Kadambi, Sourabh Bhagwan; Chen, Chun-Teh; Krishna, Gamidi Rama; Kammari, Bal Raju; Buehler, Markus J.; Ramamurty, Upadrasta; Reddy, C. Malla (Chemistry of Materials, 2019)
Distinct macroscopic mechanical responses of the three crystals of naphthalene diimide derivatives, 1Me, 1Et, and 1nPr, studied here are very intriguing because their molecular structures are very similar, with the difference only in the alkyl chain length. Among the three crystals examined, 1Me shows highly plastic bending nature, 1Et shows elastic flexibility, and 1nPr is brittle. A detailed investigation by nanoindentation and molecular dynamics (MD) simulations allowed us to correlate their distinct mechanical responses with the way the weak interactions pack in crystal structures. The elastic modulus (E) of 1Me is nearly an order of magnitude lower than that of 1Et, whereas hardness (H) is less than half. The low values of E and H of 1Me indicate that these crystals are highly compliant and offer a low resistance to plastic flow. As the knowledge of hardness and elastic modulus of molecular crystals alone is insufficient to capture their macroscopic mechanical deformation nature, that is, elastic, brittle, or plastic, we have employed three-point bending tests using the nanoindentation technique. This allowed a quantitative evaluation of flexibility of the three mechanically distinct semiconducting molecular crystals, which is important for designing larger-scale applications; these were complemented with detailed MD simulations. The elastic 1Et crystals showed remarkable flexibility even after 1000 cycles. The results emphasize that the alkyl side chains in functional organic crystals may be exploited for tuning their self-assembly as well as their mechanical properties. Hence, the study has broad implications, for example, in crystal engineering of various flexible, ordered molecular materials.

Re-purposing is needed for beneficial bugs, not for the drugs - Ram, Hari; Dastager, Syed G. (International Microbiology, 2019)
Between 150 and 200 species of plants, insects, birds or mammals go extinct every day. We do not have any idea what the global extinction rate for microorganisms is. What is clear is that we have already lost a maximum number of the microbes that used to live in and on our skins. Many of our microbial partners are facing extinction as we apply selection pressures that are unprecedented in our long-standing relationships. Recent estimates are that we have lost at least one third of the diversity of our skin microbiome. Every day, most of us bath or shower in water that contains chlorine or fluorine; these additives do a great job of killing pathogenic microbes, but they are probably not helping our skin microbiome. Most of the people apply cosmetic products every day, as these products contain preservatives that prevent microbial growth on the shelf. These same chemicals may well kill microbes on the skin. The daily use of high-pH soaps probably will not help microbial life that is adapted to living on the skin's natural pH of 5. The rise in the rate of C-section births from around 5% in 1970 to more than 30% today is likely to be a contributing factor. Vaginal microbes seed our skins at birth and C-sections disrupt this process. The overuse of broad-spectrum antibiotics has contributed to the loss of our microbial partners in all body sites and the skin is no exception. It is now clear that skin is an ecosystem that is dependent on commensal microbes for optimal health. In general, a diverse ecosystem is a healthy ecosystem that is robust in the face of change. Low-diversity ecosystems are more fragile and susceptible to dysbiosis. Eczema and acne rates have increased rapidly over the last 50 years. These diseases are almost unknown in hunter-gatherer communities. Now, we face two exciting challenges: finding out which species matter and how to get them back.
Keywords: Drugs; Dysbiosis; Microbiome; Probiotics

Retraction: a highly concise and practical route to clavaminols, sphinganine and (+)-spisulosine via indium mediated allylation of α-hydrazino aldehyde and a theoretical insight into the stereochemical aspects of the reaction - Pandey, M.; Chowdhury, P. S.; Dutta, A. K.; Kumar, P.; Pal, S. (RSC Advances, 2019)
A conceptually different approach has been employed for the synthesis of 1,2-amino alcohols by proline-catalyzed α-amination of aldehyde and one-pot indium mediated allylation of the crude α-hydrazino aldehydes. DFT based quantum chemical calculations have been performed to obtain a quantitative explanation of the stereoselectivity of the reaction.

Retraction: organocatalytic stereoselective synthesis of passifloricin A (Retraction of Vol 10, Pg 1820, 2012) - Kumar, Pradeep; Pandey, Menaka; Gupta, Priti; Dhavale, Dilip D. (Organic & Biomolecular Chemistry, 2019)

Saturated N-heterocyclic carbene based thiele's hydrocarbon with a tetrafluorophenylene linker - Kundu, Gargi; De, Sriman; Tothadi, Srinu; Das, Abhishek; Koley, Debasis; Sen, Sakya S. (Chemistry-A European Journal, 2019)
The synthesis of a SIPr [1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene] derived Kekule diradicaloid with a tetrafluorophenylene spacer (3) has been described. Two synthetic routes have been reported to access 3. The cleavage of C-F bond of C6F6 by SIPr in the presence of BF3 led to double C-F activated compound with two tetrafluoro borate counter anions (2), which upon reduction by lithium metal afforded 3. Alternatively, 3 can be directly accessed in one step by reacting SIPr with C6F6 in presence of Mg metal. Compounds 2 and 3 were well characterized spectroscopically and by single-crystal X-ray diffraction studies. Experimental and computational studies support the cumulenic closed-shell singlet state of 3 with a singlet-triplet energy gap (Delta ES-T) of 23.7 kcal mol(-1).
Keywords: C-F activation; Density functional calculations; fluorine; Kekule diradicaloids; saturated NHC

Scalable microwave-assisted continuous flow synthesis of CuO nanoparticles and their thermal conductivity applications as nanofluids - Nikam, Arun V.; Dadwal, Arun H. (Advanced Powder Technology, 2019)
We have demonstrated the novel and scalable synthesis of CuO nanoparticles by an integration of microwave and flow synthesis. The shape and size of CuO nanoparticles were tuned by changing the concentration of copper precursor. The production rate of CuO nanoparticles was found to be 5 g/h with 70% conversion of copper acetate into the CuO nanoparticles. The thermal conductivity of CuO nanofluid prepared in ethylene glycol showed linear enhancement with increase in the volume content of CuO nanoparticles produced in batch and flow reactors. (C) 2018 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.
Keywords: Flow synthesis; Microwave; Nanofluids; Nanoparticles; scale-up; Thermal conductivity

Scalable synthesis of cladosporin - Das, Pronay; Mankad, Yash; Reddy, D. Srinivasa (Tetrahedron Letters, 2019)
Cladosporin, a secondary metabolite isolated from fungal sources like Cladosporium cladosporioides and Aspergillus flavus was found to exhibit selective nano-molar activity against malarial parasite Plasmodium falciparum by inhibiting parasitic protein biosynthesis. In addition, this natural product has a broad range of bioactivities including, antiparasitic, antifungal, antibacterial as well as plant growth inhibition. However, it has limited availability from the natural sources for further development. Herein, we report a modified and improved synthetic route which led us to produce this potent natural product in a gram scale. Conversion of the undesired diastereomer to desired one via Mitsunobu inversion of secondary alcohol and carbon monoxide insertion reaction towards the construction of isocoumarin unit are the key features of the present synthesis. (C) 2019 Elsevier Ltd. All rights reserved.
Keywords: Anti-malarials; Cladosporin; Mitsunobu; Total synthesis

Selective targeting of integrin alpha v beta 8 by a highly active cyclic peptide - Reichart, Florian; Maltsev, Oleg V.; Kapp, Tobias G.; Raeder, Andreas F. B.; Weinmueller, Michael; Marelli, Udaya Kiran; Notni, Johannes; Wurzer, Alexander; Beck, Roswitha; Wester, Hans Juergen; Steiger, Katja; Di Maro, Salvatore; et al. (Journal of Medicinal Chemistry, 2019)
Integrins play important roles in physiological and pathophysiological processes. Among the RGD-recognizing integrin subtypes, the alpha v beta 8 receptor is emerging as an attractive target because of its involvement in various illnesses, such as autoimmune diseases, viral infections, and cancer. However, its functions have, so far, not been investigated in living subjects mainly because of the lack of a selective alpha v beta 8 ligand. Here, we report the design and potential medical applications of a cyclic octapeptide as the first highly selective small-molecule ligand for alpha v beta 8. Remarkably, this compound displays low nanomolar alpha v beta 8 binding affinity and a strong discriminating power of at least 2 orders of magnitude versus other RGD-recognizing integrins. Peptide functionalization with fluorescent or radioactive labels enables the selective imaging of alpha v beta 8-positive cells and tissues. This new probe will pave the way for detailed characterization of the distinct (patho)physiological role of this relatively unexplored integrin, providing a basis to fully exploit the potential of alpha v beta 8 as a target for molecular diagnostics and personalized therapy regimens.

On the sensitivity of alginate rheology to composition - Suresh, Karthika; Haering, Marleen; Kumaraswamy, Guruswamy; Diaz Diaz, David (Soft Matter, 2019)
The linear response of alginate-phenyl boronic acid (Alg-PBA) esters shows a universal, composition-independent viscoelastic fluid-like behaviour. Reversible association of alginates governs their rheology at all compositions (viz. at all alginate concentrations and solution pH). However, their high strain behaviour is very sensitive to composition. Tuning composition affords liquids that neck to form filaments capable of being drawn to large elongations without failure. We interpret our data by invoking strain-dependent association and dissociation rates for the alginates. High association rates at high strain result in materials with viscoelastic liquid like behaviour.

Size-controlled cobalt ferrite nanocrystals: magnetically separable reusable nanocatalysts for selective oxidation of styrene - Jeyavani, Vijayakrishnan; Pawar, Sayali; Dadwal, Arun; Joy, Pattayil Alias; Mukherjee, Shatabdi Porel (ChemistrySelect, 2019)
Superparamagnetic cobalt ferrite (CFO) nanocrystals (NCs) with sizes similar to 6 nm and similar to 4 nm were synthesized using a facile solvothermal method using fatty acids, lauric acid and stearic acid, as the capping agents. The synthesized nanocrystals were well characterized by XRD, FT-IR, XPS, SEM and TEM. The formation mechanism was explored and it was shown that the fatty acid was actually chemisorbed as a carboxylate onto the surface of CFO NCs. The experimental results specify that the size and size distribution of the CFO NCs were highly dependent on the length of fatty acid hydrophobic chain. Corresponding changes of the magnetic properties were investigated by measuring magnetization as a function of field and temperature, which suggest that the CFO NCs were superparamagnetic in nature. The catalytic properties for the oxidation of styrene in organic medium were examined by using the synthesized CFO NCs with sizes similar to 6 nm and similar to 4 nm. The synthesized CFO NCs, well dispersible in organic media, were demonstrated to be highly catalytically active, reached 100% conversion of styrene in 12 h with similar to 77% and similar to 82% selectivity for styrene oxide respectively. The magnetic CFO nanocatalysts were easily separated and recovered from the reaction medium by an external magnet, and reused for several cycles without losing catalytic selectivity for styrene oxide.
Keywords: Cobalt ferrite; epoxidation; Fatty acids; magnetic properties; nanocrystals

Squaraine-linked metalloporphyrin two-dimensional polymer photocatalyst for hydrogen and oxygen evolution reactions - Ranjeesh, K. C.; George, L.; Wakchaure, V. C.; Goudappagouda; Devi, R. N.; Babu, S. S. (Chemical Communications, 2019)
Efficient water splitting photocatalysts are an energetically demanding and cost-effective method for generating renewable energy. Significant research has been reported to advance this approach. However, the use of organic photocatalysts and the presence of residual catalysts trapped in the porous frameworks present major concerns about the efficiency of this strategy. Herein, we report the photocatalytic evolution of H2 and O2 by a multi-hydroxyl group-decorated metalloporphyrin-based two-dimensional catalyst developed via metal catalyst-free synthetic route. Though metalloporphyrins have long been used for catalytic functions, a heterogeneous photocatalyst delivering both H2 and O2 has not yet been realized. This polymer catalyst design enables the photocatalytic diatomic O2 release, a bottleneck in water splitting, in a facile way. Photocatalytic release of H2 as well as O2 occurs with long-term durability of 20 cycles in 300 days with negligible decrease in efficiency, thus demonstrating the excellent performance of this new catalyst.

Synthesis and biological evaluation of 2,4,5-trisubstituted thiazoles as antituberculosis agents effective against drug-resistant tuberculosis - Karale, Uttam B.; Krishna, Vagolu Siva; Krishna, E. Vamshi; Choudhari, Amit S.; Shukla, Manjulika; Gaikwad, Vikas R.; Mahizhaveni, B.; Chopra, Sidharth; Misra, Sunil; Sarkar, Dhiman; Sriram, Dharmarajan; Dusthackeer, V. N. Azger; et al. (European Journal of Medicinal Chemistry, 2019)
The dormant and resistant form of Mycobacterium tuberculosis presents a challenge in developing new anti-tubercular drugs. Herein, we report the synthesis and evaluation of trisubstituted thiazoles as antituberculosis agents. The SAR study has identified a requirement of hydrophobic substituent at C2, ester functionality at C4, and various groups with hydrogen bond acceptor character at C5 of thiazole scaffold. This has led to the identification of 13h and 13p as lead compounds. These compounds inhibited the dormant Mycobacterium tuberculosis H37Ra strain and M. tuberculosis H37Rv selectively. Importantly, 13h and 13p were non-toxic to CHO cells. The 13p showed activity against multidrug-resistant tuberculosis isolates. (C) 2019 Elsevier Masson SAS. All rights reserved.

Synthesis and characterization of zinc oxide nanoparticles by using polyol chemistry for their antimicrobial and antibiofilm activity - Mahamuni, P. P.; Patil, P. M.; Dhanavade, M. J.; Badiger, M. V.; Shadija, P. G.; Lokhande, A. C.; Bohara, R. A. (Biochemistry and Biophysics Reports, 2019)
The present investigation deals with facile polyol mediated synthesis and characterization of ZnO nanoparticles and their antimicrobial activities against pathogenic microorganisms. The synthesis process was carried out by refluxing zinc acetate precursor in diethylene glycol(DEG) and triethylene glycol(TEG) in the presence and in the absence of sodium acetate for 2 h and 3 h. All synthesized ZnO nanoparticles were characterized by X-ray diffraction (XRD), UV visible spectroscopy (UV), thermogravimetric analysis (TGA), fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy(FESEM), transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX) technique. All nanoparticles showed different degree of antibacterial and antibiofilm activity against Gram-positive Staphylococcus aureus (NCIM 2654)and Gram-negative Proteus vulgaris (NCIM 2613). The antibacterial and antibiofilm activity was inversely proportional to the size of the synthesized ZnO nanoparticles. Among all prepared particles, ZnO nanoparticles with least size (~ 15 nm) prepared by refluxing zinc acetate dihydrate in diethylene glycol for 3 h exhibited remarkable antibacterial and antibiofilm activity which may serve as potential alternatives in biomedical application.

Synthesis and reactivity of a hypersilylsilylene - Bisai, Milan Kumar; Swamy, V. S. V. S. N.; Das, Tamal; Vanka, Kumar; Gonnade, Rajesh G.; Sen, Sakya S. (Inorganic chemistry, 2019)
Stabilization of an amidinatosilylene with a bulky tris(trimethylsilyl)silyl substituent was realized with the preparation of PhC(NtBu)(2)Si{Si(SiMe3)(3)} (1) from PhC(NtBu)(2)SiHCl2 with K{Si(SiMe3)(3)} in more than 90% yield. The highly deshielded Si-29 NMR resonance (delta = 76.91 ppm) can be attributed to the absence of a pi-donating substituent. The molecular structure of 1 shows a trigonal-planar geometry around the Si-II center with a Si-II-Si-IV bond length of 2.4339(13) angstrom. A series of reactions of 1 with Me3NO, S, Se, and Te were performed. While siloxane derivatives (2 and 3) are obtained from reactions with Me3NO, silachalcogenones (4-6) are formed with other chalcogens. The presence of Si=E (E = S, Se, and Te) bonds in 4-6 have been confirmed by single crystal X-ray studies. Silaoxirane (7) formation was observed when 1 was treated with acetone, demonstrating the importance of the tris(trimethylsilyl)silyl group to kinetically and thermodynamically protect the silaoxirane derivative with less bulky substituents on the C atom.

Synthesis of a 3D free standing crystalline NiSex matrix for electrochemical energy storage applications - Dinara, Syed Mukulika; Samantara, Aneeya K.; Das, Jiban K.; Behera, J. N.; Nayak, Saroj K.; Late, Dattatray J.; Rout, Chandra Sekhar (Dalton Transactions, 2019)
The electrochemical performance for energy storage of three-dimensional (3D) self-supported heterogeneous NiSex cubic-orthorhombic nanocrystals grown by a facile one-step chemical vapour deposition (CVD) approach on Ni foam substrates has been explored. NiSex shows a high specific capacitance of 1333 F g(-1) with ultra-high energy (105 W h kg(-1)) and power (54 kW kg(-1)) densities. Furthermore, by integrating the as-grown NiSex as the anode and reduced graphene oxide as the cathode, a hybrid super-capacitor (HSC) prototype with a coin cell configuration has been fabricated. The device shows better capacitance (40 F g(-1)) with high energy (22 W h kg(-1)) and power (5.8 kW kg(-1)) densities and robust cycling durability (similar to 88% capacitance retention after 10 000 repeated cycles). For practical reliability of the as-fabricated HSC, a red LED has been illuminated by connecting it with two charged coin cells. These outstanding performances of the HSC prove to be promising for applications in high energy storage systems.

Synthesis of new 1,3,4-oxadiazole and benzothiazolylthioether derivatives of 4-arylmethylidene-3-substituted-isoxazol-5(4H)-one as potential antimycobacterial agents - Chavan, Abhijit P.; Deshpande, Rujuta R.; Borade, Nandkumar A.; Shinde, Abhijit; Mhaske, Pravin C.; Sarkar, Dhiman; Bobade, Vivek D. (Medicinal Chemistry Research, 2019)
A new series of 4-[(substituted benzylidene)-3-[(5-(pyridine-4-yl)-1,3,4-oxadiazole-2-ylthio)-methyl]i soxazol-5(4H)-one (6a-g) and 4-(substituted benzylidene)-3-((benzo[d]thiazol-2-ylthio)methyl)isoxazol-5(4H)-one (8a-g) was synthesized. All the synthesized compounds were screened for antitubercular activity against Mycobacterium tuberculosis H37Ra (ATCC 25177) and Mycobacterium bovis BCG (ATCC 35743) and antibacterial activity against Escherichia coli (NCIM 2576), Pseudomonas flurescence (NCIM 2059), Staphylococcus aureus (NCIM 2602), Bacillus subtilis (NCIM 2162). Amongst the synthesized 1,3,4-oxadiazole and benzothiazoyl thioether derivatives, compounds 6b and 8b showed excellent antimycobacterial activity and compounds 6b, 8a, 8b, and 8d showed excellent antibacterial activity against all tested antibacterial strains. The synthesized compounds were further evaluated for their cytotoxic activity against the HCT 116 and HeLa cancer cell lines. The 1,3,4-oxadiazole and benzothiazoyl thioether derivatives 6a-g and 8a-g did not show cytotoxicity.
Keywords: 1; 3; 4-Oxadiazole; antibacterial activity; Antitubercular activity; Benzothiazol; Isoxazol-5(4H)-one; Thioeteher

Taxonomic insights into the phylogeny of Bacillus badius and proposal for its reclassification to the genus Pseudobacillus as Pseudobacillus badius comb. nov. and reclassification of Bacillus wudalianchiensis Liu et al. - Verma, Ashish; Pal, Yash; Ojha, Anup Kumar; Kumari, Munesh; Khatri, Indu; Rameshkumar, N.; Schumann, Peter; Dastager, Syed G.; Mayilraj, Shanmugam; Subramanian, Srikrishna; Krishnamurthi, Srinivasan (Systematic and Applied Microbiology, 2019)
The species Bacillus badius is one of the oldest members of the genus Bacillus isolated from faeces of children and was classified based on its ability to form endospores [8]. In 16S rRNA gene sequence and phylogenetic analysis, Bacillus badius DSM 23(T) shared low similarity (93.0%) and distant relationship with B. subtilis, the type species of the genus Bacillus indicating that it does not belong to this genus. Additional strains of the species, B. badius DSM 5610, DSM 30822 and B. encimensis SGD-V-25 (which has been recently reclassified as a member of this species) were included in the study to consider intraspecies diversity. Detailed molecular phylogenetic and comparative genome analysis clearly showed that the strains of B. badius were consistently retrieved outside the cluster of Bacillus sensu stricto and also distantly related to the genera Domibacillus and Quasibacillus. Further, the data from biochemical reactions (inability to ferment most carbohydrates), polar lipids profile (presence of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an aminophosphoglycolipid) and fatty acids supported the molecular analysis. Thus the four B. badius strains; DSM 23(T), DSM 5610, DSM 30822 and SGD-V-25 displayed sufficient demarcating phenotypic characteristics that warrant their classification as members of a novel genus and single species, for which the name Pseudobacillus badius gen. nov. comb. nov. is proposed with Pseudobacillus badius DSM 23(T) (= ATCC 14574(T)) as the type strain. Additionally, based on our findings from phenotypic, chemotaxonomic and genotypic parameters, Bacillus wudalianchiensis DSM 100757(T) was reclassified as Pseudobacillus wudalianchiensis comb. nov. (C) 2019 Elsevier GmbH. All rights reserved.
Keywords: 16S rRNA; Bacillus; Bacillus wudalianchiensis; Fatty acids; polar lipids; Pseudobacillus

Terpene profiling, transcriptome analysis and characterization of cis–terpineol synthase from Ocimum - Anand, Atul; Jayaramaiah, Ramesha H.; Beedkar, Supriya D.; Dholakia, Bhushan B.; Lavhale, Santosh G.; Punekar, Sachin A.; Gade, Wasudeo N.; Thulasiram, Hirekodathakallu V.; Giri, Ashok P. (Physiology and Molecular Biology of Plants, 2019)
Ocimum species produces a varied mix of different metabolites that imparts immense medicinal properties. To explore this chemo-diversity, we initially carried out metabolite profiling of different tissues of five Ocimum species and identified the major terpenes. This analysis broadly classified these five Ocimum species into two distinct chemotypes namely, phenylpropanoid-rich and terpene-rich. In particular, -caryophyllene, myrcene, limonene, camphor, borneol and selinene were major terpenes present in these Ocimum species. Subsequently, transcriptomic analysis of pooled RNA samples from different tissues of Ocimum gratissimum, O. tenuiflorum and O. kilimandscharicum identified 38 unique transcripts of terpene synthase (TPS) gene family. Full-length gene cloning, followed by sequencing and phylogenetic analysis of three TPS transcripts were carried out along with their expression in various tissues. Terpenoid metabolite and expression profiling of candidate TPS genes in various tissues of Ocimum species revealed spatial variances. Further, putative TPS contig 19414 (TPS1) was selected to corroborate its role in terpene biosynthesis. Agrobacterium-mediated transient over-expression assay of TPS1 in the leaves of O. kilimandscharicum and subsequent metabolic and gene expression analyses indicated it as a cis–terpineol synthase. Overall, present study provided deeper understanding of terpene diversity in Ocimum species and might help in the enhancement of their terpene content through advanced biotechnological approaches.
Keywords: Agro-infiltration assay; Metabolite profiling; Ocimum; Terpene synthase; Terpenes; Transcriptome

Utilization of waste biomass for the synthesis of functionalizable support for covalent anchoring of active organo catalyst - Doke, D. S.; Advani, J. H.; Naikwadi, D. R.; Gawande, M. B.; Walke, P.; Umbarkar, S. B.; Biradar, A. V. (ACS Sustainable Chemistry & Engineering, 2019)
A single step synthetic procedure for carbon microspheres from agricultural waste residue (sugarcane bagasse) by low-temperature hydrothermal carbonization using oxalic acid as a hydrating/dehydrating agent is developed. The FTIR and XPS spectroscopy analysis indicates the presence of −OH, −COOH, and C═O functional groups on the surfaces of carbon spheres. These functional groups of the carbon spheres were utilized as a novel route to anchor 3-aminopropyl-triethoxysilane and 3-(2-aminoethylamino)propyl)-trimethoxysilane via condensation of triethoxy/trimethoxy silanes for the synthesis of organo base supported on carbon catalysts. The catalytic activity of the obtained supported organo-base catalyst was demonstrated for C–C bond forming (Henry) reaction. Among all prepared catalysts, 3-(2-aminoethylaminopropyl)-trimethoxysilane grafted in toluene showed high conversion (up to 100%) of aldehydes with excellent selectivity toward β-nitrostyrene. The catalyst was reused five times without losing significant activity for the same reaction.

Vanadium-based highly active and selective catalysts for oxidative dehydrogenation of ethyl lactate to ethyl pyruvate - Doke, Dhananjay; Khomane, Sonali B.; Pandhare, Swati; Dongare, Mohan K.; Dumeignil, Franck; Umbarkar, Shubhangi (Applied Catalysis A: General, 2019)
<span style="color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">Pyruvates are important intermediates for various bioactive and pharmaceutical molecules. Synthesis of pyruvates is challenging due to low selectivity, as the pyruvates are prone to polymerisation. In the present work, oxidative dehydrogenation of ethyl lactate to ethyl pyruvate was carried out under very mild conditions using vanadium-based homogeneous and heterogeneous catalysts in the presence of aqueous <em style="color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-size: 18px; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">t<span style="color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">-butyl hydroperoxide as an oxidant. Homogenous vanadium-based catalyst, VO(acac)<span style="font-size: 13.5px; line-height: 0; position: relative; bottom: -0.25em; color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">2<span style="color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;"> in acetonitrile solvent, gave excellent conversion (upto 83%) with 100% selectivity to ethyl pyruvate at room temperature. However, the heterogeneous catalyst, V<span style="font-size: 13.5px; line-height: 0; position: relative; bottom: -0.25em; color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">2<span style="color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">O<span style="font-size: 13.5px; line-height: 0; position: relative; bottom: -0.25em; color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">5<span style="color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;"> exhibited very high activity for oxidative dehydrogenation of ethyl lactate only at higher temperature (80 °C). At higher temperature, significant TBHP decomposition was observed if all TBHP was added in one lot. In case of ethyl lactate dehydrogenation using V<span style="font-size: 13.5px; line-height: 0; position: relative; bottom: -0.25em; color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">2<span style="color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">O<span style="font-size: 13.5px; line-height: 0; position: relative; bottom: -0.25em; color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">5<span style="color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;"> catalyst at 80 °C with two equivalents TBHP, 60% ethyl lactate conversion with 100% TBHP conversions were observed after 5 h when all TBHP was added initially in the reaction mixture. However, the ethyl lactate conversion at 80 °C, after 5 h increased to 72% when the same amount of TBHP was added batch wise over a period of 4 h, indicating improved conversion of TBHP to ethyl pyruvate. The heterogeneous catalyst, V<span style="font-size: 13.5px; line-height: 0; position: relative; bottom: -0.25em; color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">2<span style="color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">O<span style="font-size: 13.5px; line-height: 0; position: relative; bottom: -0.25em; color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">5<span style="color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;"> exhibited up to 98% conversion with 100% ethyl pyruvate selectivity at 80 °C after 10 h with 3 equivalent TBHP added batch wise. The homogeneous catalyst could not be reused while V<span style="font-size: 13.5px; line-height: 0; position: relative; bottom: -0.25em; color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">2<span style="color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">O<span style="font-size: 13.5px; line-height: 0; position: relative; bottom: -0.25em; color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;">5<span style="color: rgb(46, 46, 46); font-family: NexusSerif, Georgia, "Times New Roman", Times, STIXGeneral, "Cambria Math", "Lucida Sans Unicode", "Microsoft Sans Serif", "Segoe UI Symbol", "Arial Unicode MS", serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400;"> could be successfully recycled five times without catalytic performances loss. Oxidation proceeds by radical mechanism, as proved by experiment with radical scavenger.

Access to diverse germylenes and a six-membered dialane with a flexible beta-diketiminate - Pahar, Sanjukta; Swamy, V. S. V. S. N.; Das, Tamal; Gonnade, Rajesh G.; Vanka, Kumar; Sen, Sakya S. (Chemical Communications, 2020)
A nacnac-based tridentate ligand containing a picolyl group (L) was employed to isolate chlorogermylene (1). The reaction of1with another equivalent of GeCl2 center dot dioxane surprisingly gave pyridylpyrrolide-based chlorogermylene (2)viaC-N bond cleavage and C-C coupling, while with AlCl3, it afforded a transmetalated product,4. The reaction of L with AlH3 center dot NMe2Et led to an unusual cyclohexane type six-membered dialane heterocycle (5).

Actin-mediated microglial chemotaxis via G-protein coupled purinergic receptor in alzheimer's disease - Das, Rashmi; Chinnathambi, Subashchandrabose (Neuroscience, 2020)
Alzheimer's disease (AD) is a neurodegenerative disease mainly associated with aging, oxidative stress and genetic mutations. There are two pathological proteins involved in AD; Amyloid-beta peptide and microtubule-associated protein Tau (MAPT). The beta- and gamma-secretase enzyme cleaves the Amyloid precursor protein, which results in the formation of extracellular plaques in brain. While, Tau undergoes hyperphosphorylation and other post-translational modifications (PTMs), which eventually generates Tau oligomers, and intracellular neurofibrillary tangles (NFTs) in neurons. Moreover, the brain-resident glia and infiltrated macrophages elevate the level of CNS inflammation, which trigger the oxidative damage of neuronal circuits by reactive oxygen species (ROS) and Nitric oxide (NO). Microglia is the primary immune cell in the CNS, which is continuously surveilling the neuronal synapses and pathogen invasion. Microglia in the resting state is called `Ramified', which possess long surveilling extensions with a small cell body. But, upon activation, microglia retracts the cellular extensions and transform into round migratory cells, called as `Amoeboid' state. Activated microglia undergoes actin remodeling by forming lamellipodia and filopodia, which directs the migratory axis while podosomes formed are involved in extracellular matrix degradation for invasion. Protein-aggregates in malfunctioning synapses and in CNS milieu can be detected by microglia, which results in its activation and migration. Subsequently, the phagocytosis of synapses leads to the inflammatory burst and memory loss. The extracellular nucleotides released from damaged neurons and the cytokine-chemokine gradients allow the neighboring microglia and macrophages to migrate-infiltrate at the site of neuronal-damage. The ionotropic (P2XR) and metabotropic (P2YR) purinergic receptor recognize extracellular ATP/ADP, which propagates through the intracellular calcium signaling, chemotaxis, phagocytosis and inflammation. The P2Y receptors give `find me' or `eat me' signals to microglia to either migrate or phagocytose cellular debris. Further, the actin cytoskeleton helps microglia to mediate directed chemotaxis and neuronal repair during neurodegeneration. Hence, we aim to emphasize the connection between purinergic signaling and actin-driven mechanical movements of microglia for migration and inflammation in AD. (C) 2020 IBRO. Published by Elsevier Ltd. All rights reserved.
Keywords: actin remodeling; Alzheimer's disease; microglia; P2Y signaling; purinergic GPCRs; Tauopathy

Agro-waste extracted cellulose supported silver phosphate nanostructures as a green photocatalyst for improved photodegradation of RhB dye and industrial fertilizer effluents - Dwivedi, Pravin K.; Nair, Aathira; Mehare, Rupali S.; Chaturvedi, Vikash; Joshi, Kavita; Shelke, V. Manjusha (Nanoscale Advances, 2020)
The efficiency and reusability of photocatalysts are the dominant factors for their pragmatic use. The visible light induced semiconductor silver phosphate is a superior photocatalyst effective under visible light but its stability is still an undiscussed issue. To overcome this stability issue in this present manuscript, eco-friendly agro-waste extracted cellulose supported silver phosphate nanostructures have been designed for the first time through a simple chemical process. At first, silver phosphate nanostructures were synthesized by the co-precipitation method. Then, different weights of cellulose were added to the silver nitrate solution to form cellulose supported silver phosphate nanostructures. The photodegradation efficiency for each weight ratio was examined in which the photocatalyst Ag-8 nanostructures showed a high rate (0.024 min(-1)) for degradation of Rhodamine B (RhB) using a low intensity tungsten bulb. Real sample analysis has also been carried out using this photocatalyst for the degradation of industrial fertilizer effluents. The degradation rate of all the nanostructures was found to be high in comparison to pristine silver phosphate as well as the extracted bare cellulose. The photocatalytic activity is enhanced because of the participation of cellulose as a support which makes an interface for silver phosphate and assists it in delaying the charge recombination period under visible light. To understand the photochemical reaction of electrons and holes, scavenger studies were also performed.

AIE emission of SDS capped diphenylanthracene nanoparticles for selective recognition and estimation of Al(3+)ion in aqueous medium based on enhancement effect and analytical application - Suryawanshi, Sonali B.; Deshmukh, Gunvant R.; Bodake, Anita J.; Patil, Shivajirao R. (Macromolecular Symposia, 2020)
The sodium dodecyl sulfate capped 9,10 Diphenylanthracene nanoparticles is prepared by using reprecipitation method. The average particle size of NPs obtained from DLS examination is 67 nm. The aqueous suspension of NPs exhibits red shifted aggregation induces enhanced emission. The zeta potential value-42.9 mV indicates stability of NPs and generation of expected negative surface charge over the NPs to attract and adsorb cations from the solution on the surface. The cation recognition test based on fluorescence shows that the presence of Al(3+)ion significantly enhances the fluorescence of NPs. Furthermore, the proposed system is successfully applied for the detection of Al(3+)ion from environmental water samples and Digene table available in the market. The advantage of developed analytical method is lower value of LOD and even in presence of interfering ion Mg(2+)the Al(3+)is estimated with no need of their separation prior to analysis.
Keywords: 10-Diphenyl anthracene nanoparticles; aggregation induced enhanced emission; Al(3+)detection; fluorescence enhancement; SDS capped 9

Alpha-Angelica lactone catalyzed oxidation of benzylic sp(3) C-H bonds of isochromans and phthalans - Thatikonda, Thanusha; Deepake, Siddharth K.; Kumar, Pawan; Das, Utpal (Organic & Biomolecular Chemistry, 2020)
A metal-free organocatalytic system has been developed for highly efficient benzylic C-H oxygenations of cyclic ethers using oxygen as an oxidant. This oxidation reaction utilizes alpha-angelica lactone as a low cost/low molecular weight catalyst. The optimized reaction conditions allow the synthesis of valued isocoumarins and phthalides from readily available precursors in good yields. Mechanistic studies indicate that the reaction pathway likely involves a radical process via a peroxide intermediate.

Amphiphilic mannose-6-phosphate glycopolypeptide-based bioactive and responsive self-assembled nanostructures for controlled and targeted lysosomal cargo delivery - Mondal, Basudeb; Pandey, Bhawana; Parekh, Nimisha; Panda, Sidharth; Dutta, Tahiti; Padhy, Abinash; Sen Gupta, Sayam (Biomaterials Science, 2020)
Receptors of carbohydrate mannose-6-phosphate (M6P) are overexpressed in specific cancer cells (such as breast cancer) and are also involved in the trafficking of mannose-6-phosphate labeled proteins exclusively onto lysosomes via cell surface M6P receptor (CI-MPR) mediated endocytosis. Herein, for the first time, mannose-6-phosphate glycopolypeptide ((M6P)GP)-based bioactive and stimuli-responsive nanocarriers are reported. They are selectively taken up via receptor-mediated endocytosis, and trafficked to lysosomes where they are subsequently degraded by pH or enzymes, leading to the release of the cargo inside the lysosomes. Two different amphiphilic M6P block copolymers (M6P)GP(15)-(PPO44)-P-A and (M6P)GP(15)-(PCL25)(2) were synthesized by click reaction of the alkyne end-functionalized (M6P)GP(15) with pH-responsive biocompatible azide end-functionalized acetal PPO and azide end-functionalized branched PCL, respectively. In water, the amphiphilic M6P-glycopolypeptide block copolymers self-assembled into micellar nanostructures, as was evidenced by DLS, TEM, AFM, and fluorescence spectroscopy techniques. These micellar systems were competent to encapsulate the hydrophobic dye rhodamine-B-octadecyl ester, which was used as the model drug. They were stable at physiological pH but were found to disassemble at acidic pH (for (M6P)GP(15)-(PPO44)-P-A) or in the presence of esterase (for (M6P)GP(15)-(PCL25)(2)). These (M6P)GP based micellar nanoparticles can selectively target lysosomes in cancerous cells such as MCF-7 and MDA-MB-231. Finally, we demonstrate the clathrin-mediated endocytic pathway of the native FL-(M6P)GP polymer and RBOE loaded (M6P)GP micellar-nanocarriers, and selective trafficking of MCF-7 and MDA-MB-231 breast cancer cell lysosomes, demonstrating their potential applicability toward receptor-mediated lysosomal cargo delivery.

Anthrone-spirolactam and quinoline hybrid based sensor for selective fluorescent detection of Fe(3+)ions - Darole, Ratanamala S.; Christopher Leslee, Denzil Britto; Mukherjee, Anagh; Gonnade, Rajesh G.; Karuppannan, Sekar; Senthilkumar, Beeran (2020)
The synthesis of a novel, and highly selective Fe(3+)ion sensor based on anthrone-spirolactam and its quinoline hybrid ligand is reported. The designed ligand displayed selective detection of Fe(3+)ions with enhanced fluorescence emission. The complexation of Fe(3+)ion led to a red shift of 32 nm from 420 nm to 452 nm, and a several fold increase in intensity with fluorescent green emission. The complexation (detection) of Fe(3+)ions with ligand resulted in chelation enhanced fluorescence and intramolecular charge transfer through the inhibition of C=N isomerization. This hybrid sensor shows high sensitivity and selectivity, spontaneous response, and works on a wide pH range a minimum detection limit of 6.83 x 10(-8)M. Importantly, the sensor works through the fluorescence turn-on mechanism that overcomes the paramagnetic effect of Fe(3+)ions. The binding mechanism between the ligand and the Fe(3+)ions was established from the Job's plot method, optical studies, Fourier transfor infrared spectroscopy, NMR titration, fluorescence life-time studies, and density functional theory optimization. The sensor displayed excellent results in the quantification of Fe(3+)ions from real water samples. Furthermore, due to its biocompatibility nature, fluorescent spotting of Fe(3+)ions in live cells revealed its bioimaging applications.
Keywords: anthrone-spirolactam-quinoline; Cell imaging; fluorescence; intramolecular charge transfer; iron

Antibacterial properties of glycosylated surfaces: variation of the glucosidal moiety and fatty acid conformation of grafted microbial glycolipids - Valotteau, Claire; Roelants, Sophie L. K. V.; Dhasaiyan, Prabhu; Zibek, Susanne; Guenther, Michael; Soetaert, Wim; Everaert, Bernd; Pradier, Claire-Marie; Babonneau, Florence; Baccile, Niki; Humblot, Vincent (Molecular Systems Design & Engineering, 2020)
Glycosylated surfaces can display antimicrobial properties. It has been shown that sophorolipids can be used to develop biocidal coatings against Gram-positive and Gram-negative bacteria, but with a limited efficiency so far. Therefore, it appears necessary to further investigate the surface antibacterial activity of a broader set of structurally related glycolipids. The present work explores the influence of the glucosidic moiety (gluco-, sophoro-, cellobio-) and the fatty acid backbone (saturated,cisortransmonounsaturated). We show that the fatty acid backbone plays an important role:cisderivative of sophorolipids (SL) grafted onto model gold surfaces has better biocidal properties than saturated (SL0) andtransmonounsaturated (SLt) molecules, which appear to be inefficient. The number of glucose units is also a key factor: a one-third decrease in antibacterial activity is observed when having one glucose unit (GL) compared to two (SL). Sugar acetylation (SLa) does not seem to have an impact on the biocidal properties of surfaces. These results are not limited to sophorolipids, with cellobioselipids (CL) leading to similar antibacterial observations.

Antimicrobial profiling of coral reef and sponge associated bacteria from southeast coast of India - Rajasabapathy, Raju; Ghadi, Sanjeev C.; Manikandan, Balakrishnan; Mohandass, Chellandi; Surendran, Akhila; Dastager, Syed G.; Meena, Ram M.; James, Rathinam Arthur (2020)
Culturable bacteria associated with marine sponges and coral mucus (collected from Gulf of Mannar and Palk Bay) were screened for their prospective antimicrobial compounds against 9 bacterial pathogens (Bacillus megaterium, B. cereus, Salmonella typhimurium, Staphylococcus aureus, Proteus vulgaris, Klebsillla pneumoniae, Escherichia coli, Pseudomonas aeruginosa and Acinetobacter baumannii) and a fungal pathogen (Candida albicans). Of the 263 bacterial isolates obtained during this study, 52 isolates displayed antimicrobial activity against one or more pathogens. 16S rRNA gene sequencing revealed that these 52 strains affiliated to 14 genera from three phyla Proteobacteria, Firmicutes and Actinobacteria. Sponge associated bacterial strains F-04, 1-23, 1-33 and G-03 inhibited the growth of all the bacterial pathogens tested in this study and significantly the former 2 strains inhibited the growth of fungal pathogen also. Majority of the potential strains (88.4% out of 52 strains) inhibited the growth of Bacillus cereus. Interestingly, an actinomycete strain F-04 (isolated from sponge Orina sagittaria) inhibited the growth of methicillin resistant Staphylococcus aureus. In total, 10 volatile organic compounds were determined from the ethyl acetate and hexane extract of the strain F-04 using GC-MS. Overall, marine bacteria isolated during this study demonstrate the potential for the development of broad spectrum antibiotics.
Keywords: Anti-MRSA; Antimicrobial activity; Bacterial diversity; Coral reef; Sponge

Approach to nigericin derivatives and their therapeutic potential - Sahu, Amit Kumar; Said, Madhukar S.; Hingamire, Tejashri; Gaur, Megha; Khan, Abujunaid; Shanmugam, Dhanasekaran; Barvkar, Vitthal T.; Dharne, Mahesh S.; Bharde, Atul A.; Dastager, Syed G. (RSC Advances, 2020)
A new nigericin analogue that has been chemically modified was synthesized through a fluorination process from the parent nigericin, produced from a novel Streptomyces strain DASNCL-29. Fermentation strategies were designed for the optimised production of nigericin molecule and subjected for purification and structural analysis. The fermentation process resulted in the highest yield of nigericin (33% (w/w)). Initially, nigericin produced from the strain DASNCL-29 demonstrated polymorphism in its crystal structure, i.e., monoclinic and orthorhombic crystal lattices when crystallised with methanol and hexane, respectively. Furthermore, nigericin produced has been subjected to chemical modification by fluorination to enhance its efficacy. Two fluorinated analogues revealed that they possess a very potent antibacterial activity against Gram positive and Gram negative bacteria. To date, the nigericin molecule has not been reported for any reaction against Gram-negative bacteria, which are increasingly becoming resistant to antibiotics. For the first time, fluorinated analogues of nigericin have shown promising activity. In vitro cytotoxicity analysis of fluorinated analogues demonstrated tenfold lesser toxicity than the parent nigericin. This is the first type of study where the fluorinated analogues of nigericin showed very encouraging activity against Gram-negative organisms; moreover, they can be used as a candidate for treating many serious infections.

Bacterial biofilm formation using PCL/curcumin electrospun fibers and its potential use for biotechnological applications - Pompa-Monroy, Daniella Alejandra; Figueroa-Marchant, Paulina Guadalupe; Dastager, Syed G.; Thorat, Meghana Namdeo; Iglesias, Ana Leticia; Miranda-Soto, Valentin; Perez-Gonzalez, Graciela Lizeth; Villarreal-Gomez, Luis Jesus (Materials, 2020)
Electrospun nanofibers are used for many applications due to their large surface area, mechanical properties, and bioactivity. Bacterial biofilms are the cause of numerous problems in biomedical devices and in the food industry. On the other hand, these bacterial biofilms can produce interesting metabolites. Hence, the objective of this study is to evaluate the efficiency of poly (x190;- caprolactone)/Curcumin (PCL/CUR) nanofibers to promote bacterial biofilm formation. These scaffolds were characterized by scanning electron microscopy (SEM), which showed homogeneous fibers with diameters between 441-557 nm; thermogravimetric analysis and differential scanning calorimetry (TGA and DSC) demonstrated high temperature resilience with degradation temperatures over >350 degrees C; FTIR and H-1-NMR serve as evidence of CUR incorporation in the PCL fibers. PCL/CUR scaffolds successfully promoted the formation of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa biofilms. These results will be valuable in the study of controlled harvesting of pathogenic biofilms as well as in metabolites production for biotechnological purposes.
Keywords: Bacteria; curcumin; electrospinning; Escherichia coli; Pseudomona aeruginosa; Staphylococcus aureus

Basic limonoid modulates chaperone-mediated proteostasis and dissolve Tau fibrils - Gorantla, Nalini Vijay; Das, Rashmi; Chidambaram, Hariharakrishnan; Dubey, Tushar; Mulani, Fayaj A.; Thulasiram, V. Hirekodathakallu; Chinnathambi, Subashchandrabose (Scientific Reports, 2020)
The Alzheimer's disease pathology is associated with accumulation of intracellular neurofibrillary tangles and extracellular senile plaques. The formation of initial nucleus triggers conformational changes in Tau and leads to its deposition. Hence, there is a need to eliminate these toxic proteins for proper functioning of neuronal cells. In this aspect, we screened the effect of basic limonoids such as gedunin, epoxyazadiradione, azadirone and azadiradione on inhibiting Tau aggregation as well as disintegration of induced Tau aggregates. It was observed that these basic limonoids effectively prevented aggregates formation by Tau and also exhibited the property of destabilizing matured Tau aggregates. The molecular docking analysis suggests that the basic limonoids interact with hexapeptide regions of aggregated Tau. Although these limonoids caused the conformational changes in Tau to beta-sheet structure, the cytological studies indicate that basic limonoids rescued cell death. The dual role of limonoids in Tau aggregation inhibition and disintegration of matured aggregates suggests them to be potent molecules in overcoming Tau pathology. Further, their origin from a medicinally important plant neem, which known to possess remarkable biological activities was also found to play protective role in HEK293T cells. Basic limonoids were non-toxic to HEK293T cells and also aided in activation of HSF1 by inducing its accumulation in nucleus. Western blotting and immunofluorescence studies showed that HSF1 in downstream increased the transcription of Hsp70 thus, aggravating cytosolic Hsp70 levels that can channel clearance of aberrant Tau. All these results mark basic limonoids as potential therapeutic natural products.

Bioinspired synthesis of multifunctional silver nanoparticles for enhanced antimicrobial and catalytic applications with tailored SPR properties - Parit, S. B.; Karade, V. C.; Patil, R. B.; Pawar, V. N.; Dhavale, R. P.; Tawre, M.; Pardesi, K.; Jadhav, U. U.; Dawkar, V. V.; Tanpure, R. S.; Kim, J. H.; Jadhav, J. P.; et al. (Materials Today Chemistry, 2020)
In the developing nanotechnology world, numerous attempts have been made to prepare the nobel metallic nanoparticles (NPs), which can improve their applicability in diverse fields. In the present work, the biosynthesis of silver (Ag) NPs has been successfully achieved through the medicinal plant extract (PE) of G. resinifera and effectively used for the catalytic and antibacterial applications. The size dependant tuneable surface plasmon resonance (SPR) properties attained through altering precursor concentrations. The X-ray and selected area diffraction pattern for Ag NPs revealed the high crystalline nature of pure Ag NPs with dominant (111) phase. The high-resolution TEM images show the nonspherical shape of NPs shifting from spherical, hexagonal to triangular, with wide particle size distribution ranging from 13 to 44 nm. Accordingly, the dual-band SPR spectrum is situated in the UV-Vis spectra validating the non-spherical shape of Ag NPs. The functional group present on the Ag NPs surface was analysed by FT-IR confirms the capping and reducing ability of methanolic PE G. resinifera. Further, the mechanism of antimicrobial activity studied using electron microscope showed the morphological changes with destructed cell walls of E. coli NCIM 2931 and S. aureus NCIM 5021 cells, when they treated with Ag NPs. The Ag NPs were more effective against S. aureus and E. coli with MIC 128 mu g/ml as compared to P. aeruginosa NCIM 5029 with MIC 256 mu g/ml. Apart from this, the reduction of toxic organic pollutant 4-NP to 4-AP within 20 min reveals the excellent catalytic activity of Ag NPs with rate constant k = 15.69 s(-1). (C) 2020 Elsevier Ltd. All rights reserved.
Keywords: Ag NPs; Antibacterial; Catalytic activity; Gardenia resinifera; surface plasmon resonance

Biosensors: frontiers in rapid detection of COVID-19 - Samson, Rachel; Navale, Govinda R.; Dharne, Mahesh S. (3 Biotech, 2020)
The rapid community-spread of novel human coronavirus 2019 (nCOVID19 or SARS-Cov2) and morbidity statistics has put forth an unprecedented urge for rapid diagnostics for quick and sensitive detection followed by contact tracing and containment strategies, especially when no vaccine or therapeutics are known. Currently, quantitative real-time polymerase chain reaction (qRT-PCR) is being used widely to detect COVID-19 from various types of biological specimens, which is time-consuming, labor-intensive and may not be rapidly deployable in remote or resource-limited settings. This might lead to hindrance in acquiring realistic data of infectivity and community spread of SARS-CoV-2 in the population. This review summarizes the existing status of current diagnostic methods, their possible limitations, and the advantages of biosensor-based diagnostics over the conventional ones for the detection of SARS-Cov-2. Novel biosensors used to detect RNA-viruses include CRISPR-Cas9 based paper strip, nucleic-acid based, aptamer-based, antigen-Au/Ag nanoparticles-based electrochemical biosensor, optical biosensor, and Surface Plasmon Resonance. These could be effective tools for rapid, authentic, portable, and more promising diagnosis in the current pandemic that has affected the world economies and humanity. Present challenges and future perspectives of developing robust biosensors devices for rapid, scalable, and sensitive detection and management of COVID-19 are presented in light of the test-test-test theme of the World Health Organization (WHO).
Keywords: Biosensors; COVID-19; Rapid detection; SARS-CoV-2

Bis(silanetellurone) with C-H center dot center dot center dot Te Interaction - Ghosh, Moushakhi; Panwaria, Prakash; Tothadi, Srinu; Das, Aloke; Khan, Shabana (Inorganic Chemistry, 2020)
Herein, we report the synthesis of a series of bis(silanechalcogenones) [Ch = Te (2), S (3), or Se (4)] using an N-heterocyclic silylene-based SiCSi pincer ligand (1). 2 is the first example of a bis(silanetellurone) derivative. The bonding patterns of 2-4 were extensively studied by natural bond orbital, quantum theory of atoms in molecules, and noncovalent interaction index analyses, and these exhibit weak C-H center dot center dot center dot Ch interaction. The analogous reaction of 1 with trimethyl N-oxide produced a novel bis(cyclosiloxane) derivative (5). All of the complexes are duly characterized by single-crystal X-ray diffraction studies, multinuclear nuclear magnetic resonance (H-1, C-13, and Si-29) spectroscopy, and high-resolution mass spectrometry.

Carbon supported size-controlled ru catalysts for selective levulinic acid hydrogenation into γ-valerolactone - Simakova, Irina L.; Demidova, Yuliya S.; Simonov, Mikhail N.; Niphadkar, Prashant S.; Bokade, Vijay V.; Devi, Nandini; Dhepe, Paresh L.; Murzin, Dmitry Yu (Journal of Siberian Federal University-Chemistry, 2020)
Liquid phase levulinic acid hydrogenation into γ-valerolactone in 1,4-dioxane as a solvent (165°C, 20 bar) was studied over a range of Ru monometallic catalysts using mesoporous carbon material Sibunit as a support. In addition to the catalyst prepared by impregnation with RuCl3∙nH2O (0.1 M) followed by reduction in H2, size-controlled Ru(NPs)/Sibunit catalysts were synthesized by immobilization of polyvinylpyrrolidone (PVP) stabilized Ru nanoparticles (NPs) (dRu=2.4 nm). Сarbon supported colloidal Ru NPs were not studied earlier in levulinic acid hydrogenation. Activity of colloidal Ru(NPs)/Sibunit catalysts was found to be lower than that of impregnated Ru/Sibunit which could be attributed to hampering effect of PVP. However, colloidal Ru(NPs)/Sibunit purified by thermal treatment in air (180°C) followed by reduction in H2 (400°C) exhibited the same activity as impregnated one yielding 93% γ-valerolactone at 100% levulinic acid conversion. Applicability of supported PVP-assisted colloidal Ru NPs in hydrogenation of levulinic acid illustrates a potential to prepare more efficient catalysts for this reaction with a desired particle size. The catalysts were characterized by TEM, XRF, and N2 physisorption to compare their physical chemical properties.

Catalyst-free regioselective [3+2] cycloadditions of alpha,beta-unsaturated N-arylnitrones with alkenes to access functionalized isoxazolidines: a DFT study - Ghosh, Arnab; Mane, Manoj V.; Rode, Haridas B.; Patil, Siddappa A.; Sridhar, Balasubramanian; Dateer, Ramesh B. (Chemistry-An Asian Journal, 2020)
The catalyst-free regioselective [3+2]-cycloaddition of alpha,beta-unsaturated N-arylnitrones with alkenes are developed. The series of synthetically important functionalized isoxazolidines are prepared in good to excellent yields by step economic pathway under ligand and transition-metal-free conditions. The regioselective cycloaddition pathway supported by control experiment and computational study.
Keywords: DFT study; isoxazolidines; metal and ligand free; nitrone cycloaddition; Regioselective

Catalytic conversion of HMF into ethyl levulinate - a biofuel over hierarchical zeolites - Chithra, P. A.; Darbha, Srinivas (Catalysis Communications, 2020)
Catalytic conversion of 5-hydroxymethyl-2-furfuraldehyde (HMF, a biomass-derived platform chemical) into ethyl levulinate (EL) is an attractive approach for producing renewable transport fuels for mitigating global warming. We report here the application of hierarchical zeolites (DZSM-5 and MZSM-5 synthesized by desilication and mesoporous templating approaches, respectively) as solid acid catalysts for this transformation. Hierarchical structure of these zeolites was confirmed by X-ray diffraction, nitrogen-physisorption and electron microscopy, and acidity was determined by temperature-programmed desorption of ammonia. HMF conversion of 94.2% with EL selectivity of 90.8% was achieved over the MZSM-5 catalyst. Acidity, pore size and surface properties affected the catalytic activity.
Keywords: 5-Hydroxymethyl-2-furfuraldehyde (HMF); Biofuel; ethyl levulinate; Hierarchical zeolite; ZSM-5

Catalytic hydrogenation of cinnamic acid and salicylic acid - Shinde, Sunil; Deshpande, Raj M. (Asian Journal of Chemistry, 2020)
Hydrogenation of cinnamic acid and salicylic acid was carried out using 5 %Ru/C, 5 % Pd/C and Ru-Sn/Al2O3 catalyst at 493 K and 6.89 MPa of hydrogen partial pressure. Ru-Sn/Al2O3 catalyst was found to be active for hydrogenation -COOH group to give cinnamyl alcohol. The selectivity to cinnamyl alcohol was low (15 %) as absolute inhibition of C=C bond hydrogenation in cinnamic acid is challenging. 5 %Pd/C catalyst was found to hydrogenate C=C bond and aromatic ring in cinnamic acid. 5 %Ru/C catalyst was found to be least selective catalyst as it hydrogenated C=C bond, aromatic ring and -COOH group in cinnamic acid. Hydrogenation of salicylic acid is not possible at 493 K as decarboxylation of salicylic acid occurs.

Catalytic reductive deoxygenation of esters to ethers driven by hydrosilane activation through non-covalent interactions with a fluorinated borate salt - Rysak, Vincent; Dixit, Ruchi; Trivelli, Xavier; Merle, Nicolas; Agbossou-Niedercorn, Francine; Vanka, Kumar; Michon, Christophe (Catalysis Science & Technology, 2020)
We report the catalytic and transition metal-free reductive deoxygenation of esters to ethers through the use of a hydrosilane and a fluorinated borate BArF salt as a catalyst. Experimental and theoretical studies support the role of noncovalent interactions between the fluorinated catalyst, the hydrosilane and the ester substrate in the reaction mechanism.

Chapter 9 - CRISPR-Cas9 for therapy: the challenges and ways to overcome them - Sundaram Acharya; Souvik Maiti; Debojyoti Chakraborty (Genome Engineering via CRISPR-Cas9 System, 2020)
Clustered regularly interspaced short palindromic repeat/CRISPR-associated (CRISPR Cas) is a component of the prokaryotic adaptive immune system which has been repurposed for genome editing in recent years. The precision, simplicity and flexibility of this system have opened up a broad range of biological applications covering basic research to biotechnology and medicine. Additionally, the multiplexing capabilities of CRISPR offers a promising approach for modeling or correcting common polygenic disorders along with its monogenic and infectious counterparts. Although CRISPR is not completely precise and questions remain regarding its specificity and modes of delivery, the robustness and wide applicability of this genome editing tool has opened up numerous ways to address these issues. In this chapter, we will discuss about initial progress toward CRISPR therapeutics, existing delivery modalities, the challenges before CRISPR editing before it becomes a therapeutic possibility and the ongoing efforts toward developing a perfect CRISPR system for bench to bedside application.
Keywords: CRISPR therapeutics; CRISPR-Cas9; iPSC