Synthesis, resolution, and applications of 3-amino-2,2-dimethy1-1,3-diphenylpropan-1-ol, a conformationally restricted 1,3-aminoalcohol - Patil, M. N.; Gonnade, Rajesh G.; Joshi, Navalkishore N. (Tetrahedron, 2010)
Efficient synthetic routes to both syn and anti diastereomers of a conformationally restricted 1,3-aminoalcohol were devised. Resolution of the aminoalcohols was accomplished through diastereomeric salt with R-(-)-O-acetyl mandelic acid. These aminoalcohols were examined as ligands for two standard reactions, namely, enantioselective addition of Et(2)Zn to aldehydes and reduction of prochiral ketones with BH(3). (C) 2010 Elsevier Ltd. All rights reserved.
Keywords: 1; 3-Aminoalcohol; Aldol-Tishchenko reaction; Diethylzinc; Oxazaborinane; Resolution

Synthetic studies of superstolide A: a carbohydrate based synthesis of the C21-C26 segment - Pal, Rita; Rahaman, Hasibur; Mohapatra, Debendra K.; Gurjar, Mukund K. (Letters in Organic Chemistry, 2010)
The synthesis of C21-C26 fragment of superstolide A, starting from D-glucose diacetonide, involving regioselective ring opening of epoxide by Grignard reagent and regioselective stereospecefic hydroboration oxidation has been described.
Keywords: Chiral pool; Potent cytotoxic; Regioselective epoxide opening; Stereoselective hydroboration-oxidation; Superstolide A

Template assisted highly ordered novel self assembly of micro-reservoirs and its replication - Hire, Santosh L.; Shelke, Manjusha V.; Kale, Vinayak S.; Galopin, Elisabeth; Kulkarni, Mohan G.; Boukherroub, Rabah; Ogale, Satishchandra B. (Lab on a Chip, 2010)
A novel method is developed for template assisted fabrication of a regular assembly of microcavity arrays. Simple micropatterns on PDMS mold are used to create complex geometries via solvent vapor back pressure in a biodegradable polymer. Cavities are in turn replicated in complimentary PDMS mushroom like microstructures.

Template-assisted synthesis and characterization of passivated nickel nanoparticles - Gopalan, E. Veena; Malini, K. A.; Santhoshkumar, G.; Narayanan, T. N.; Joy, Pattayil Alias; Al-Omari, I. A.; Kumar, D. Sakthi; Yoshida, Yasuhiko; Anantharaman, Maliemadom R. (Nanoscale Research Letters, 2010)
Potential applications of nickel nanoparticles demand the synthesis of self-protected nickel nanoparticles by different synthesis techniques. A novel and simple technique for the synthesis of self-protected nickel nanoparticles is realized by the inter-matrix synthesis of nickel nanoparticles by cation exchange reduction in two types of resins. Two different polymer templates namely strongly acidic cation exchange resins and weakly acidic cation exchange resins provided with cation exchange sites which can anchor metal cations by the ion exchange process are used. The nickel ions which are held at the cation exchange sites by ion fixation can be subsequently reduced to metal nanoparticles by using sodium borohydride as the reducing agent. The composites are cycled repeating the loading reduction cycle involved in the synthesis procedure. X-Ray Diffraction, Scanning Electron Microscopy, Transmission Electron microscopy, Energy Dispersive Spectrum, and Inductively Coupled Plasma Analysis are effectively utilized to investigate the different structural characteristics of the nanocomposites. The hysteresis loop parameters namely saturation magnetization and coercivity are measured using Vibrating Sample Magnetometer. The thermomagnetization study is also conducted to evaluate the Curie temperature values of the composites. The effect of cycling on the structural and magnetic characteristics of the two composites are dealt in detail. A comparison between the different characteristics of the two nanocomposites is also provided.
Keywords: Nickel nanoparticles; Polymer-metal nanocomposites; Strongly acidic cation exchange resin; Stuctural and magnetic properties; Weakly acidic cation exchange resin

Transport of yttrium metal ions through fibers supported liquid membrane solvent extraction - Gaikwad, Abaji G.; Rajput, A. M. (Journal of Rare Earths, 2010)
A novel idea of transport of yttrium (III) metal ions through fibers supported liquid membrane in two stage processes namely source to membrane and membrane to receiving phase has been proposed. The fibers supported liquid membrane was impregnated with different concentrations carrier. The experimental variables explored were concentration of yttrium (III) ions, pH of source phase, PC-88A concentration in membrane phase, acid concentration in receiving phase and stirring speed. The pre-concentration of yttrium MO ions was investigated from the dilute solutions. The two-channel fibers supported liquid membrane solvent extraction was investigated for the transport of yttrium (III) ions from the source to membrane and membrane to receiving phase. The transport of yttrium (III) ions was observed through the fibers supported liquid membrane with capillary action.
Keywords: channel; extraction; fibers supported liquid membrane solvent extraction; PC-88A; rare earths; stripping; yttrium metal ion

Uncatalyzed synthesis of thiomorpholide using polyethylene glycol as green reaction media - Gawande, Shrikant S.; Bandgar, Babasaheb P.; Kadam, Prasad D.; Sable, Shailesh S. (Green Chemistry Letters and Reviews, 2010)
Polyethylene glycol-600 was used as an efficient and recyclable solvent for the one-pot three component condensation reactions of aryl alkyl ketones, sulfur, and morpholine to produce the corresponding thiomorpholide. This protocol has advantages of high yields, short reaction times, mild reaction conditions, minimal environmental pollution, and simple work up procedure. [GRAPHICS] .
Keywords: polyethylene glycol-600; Sulfur; thiomorpholide; Willgerodt-Kindler reaction

Understanding the genetic structure of symplocos laurina wall. populations using nuclear gene markers - Banu, Sofia; Bhagwat, Rasika M.; Kadoo, Narendra Y.; Lagu, Meena D.; Gupta, V. S. (Genetica, 2010)
To characterize the genetic diversity of present populations of Symplocos laurina, which grow in the montane forests in India, we analyzed the DNA sequences of a nuclear gene. Using the 881 bp sequence of cytosolic Glyceraldehyde-3-phosphate dehydrogenase gene, we detected 24 haplotypes among 195 individuals sampled from 14 populations. Two dominant haplotypes were distributed over the entire range of this species in India and several private haplotypes were found. Low genetic diversity within population, high differentiation, number of population specific haplotypes and deviation from neutral evolution characterized the present populations of S. laurina. An analysis of molecular variance indicated the presence of geographic structure within the haplotype distribution. The occurrence of S. laurina preglaciation in India is the most parsimonious explanation for the current geographic structure observed. The populations are presumably ancient and might have spread across its extant distribution range in India through a recent range expansion event.
Keywords: GapC; Genetic diversity; Glaciation; Refugium

Unusual central indian drought of summer monsoon 2008: role of southern tropical indian ocean warming - Rao, Suryachandra A.; Chaudhari, Hemantkumar S.; Pokhrel, Samir; Goswami, B. N. (Journal of Climate, 2010)
While many of the previous positive Indian Ocean dipole (IOD) years were associated with above (below)normal monsoon rainfall over central (southern) India during summer monsoon months [June-September (JJAS)], the IOD event in 2008 is associated with below (above)-normal rainfall in many parts of central (southern peninsular) India. Because understanding such regional organization is a key for success in regional prediction, using different datasets and atmospheric model simulations, the reasons for this abnormal behavior of the monsoon in 2008 are explored. Compared to normal positive IOD events, sea surface temperature (SST) and rainfall in the southern tropical Indian Ocean (STIO) in JJAS 2008 were abnormally high. Downwelling Rossby waves and oceanic heat advection played an important role in warming SST abnormally in the STIO. It was also found that the combined influence of a linear warming trend in the tropical Indian Ocean and warming associated with the IOD have resulted in abnormal warming of the STIO. This abnormal SST warming resulted in enhancement of convection in the southwest tropical Indian Ocean and forced anticyclonic circulation anomalies over the Bay of Bengal and central India, leading to suppressed rainfall over this region in JJAS 2008. The above mechanism is tested by conducting several model sensitivity experiments with an atmospheric general circulation model (AGCM). These experiments confirmed that the subsidence over central India and the Bay of Bengal was forced mainly by the anomalous warming in the STIO region driven by coupled ocean-atmosphere processes. This study provides the first evidence of combined Indian Ocean warming, associated with global warming, and IOD-related warming influence on Indian summer monsoon rainfall. The combined influence may force below-normal rainfall over central India by inducing strong convection in the STIO region. The conventional seesaw in convection between the Indian subcontinent and the eastern equatorial Indian Ocean may shift to the central equatorial Indian Ocean and the Bay of Bengal if the central Indian Ocean consistently warms in the global warming scenario.

Vice to virtue: intracellular biogenic nanoparticles for the generation of carbon supported catalysts - Vijayakumar, P. S.; Selvakumar, S.; Gholap, Ramkrishna S.; Singh, A. P.; Bhagavatula L. V. Prasad (Journal of Nanoscience and Nanotechnology, 2010)
Intracellular biogenic nanoparticles are considered disadvantageous as the separation of the nanoparticles from the biomass becomes intricate. However realizing the importance of carbon supported catalyst for many important organic reactions we envisaged these nanoparticles as a source for carbon supported catalyst. Herein we demonstrate the heat treatment of intracellular biogenic nanoparticles under inert atmosphere as an efficient method for the preparation of carbon supported metal oxide catalysts. Aspergillus ochraceus, a fungus isolated from foundries, on incubation with K(2)TiF(6) led to the synthesis of intracellular titanium oxide nanoparticles. The nanoparticles embedded biomass upon heat treatment at 600 degrees C in a nitrogen environment gave titanium oxide nanoparticles implanted in a carbonaceous matrix. The material thus formed was characterized using FTIR spectroscopy, Raman spectroscopy, HRTEM and X-ray diffraction. Appreciable benzaldehyde selectivity was observed when styrene oxidation was carried out over such immobilized catalysts. The conversion rate was determined to be 76% and the benzaldehyde selectivity was greater than 80%.
Keywords: Benzaldehyde Selectivity; Biosynthesis; Carbon Supported Titania; Nanoparticles; Styrene Oxidation

Water-induced switching of beta-structure to polyproline II conformation in the 4s-aminoproline polypeptide via H-bond rearrangement - Sonar, Mahesh V.; Ganesh, Krishna N. (Organic Letters, 2010)
4S-Aminoproline polypeptide 2 forms unusual beta-structure in trifluoroethanol that switches to the polyproline II (PPII) form in aqueous medium. while 4R-aminoproline peptide 1 retains PPII form in both solvents. This first instance of a polyproline derivative showing a beta-structure is attributed to competitive pH-dependent (4-NH3+/NH2) stereoelectronic effect (4R vs 4S) and the overriding importance of stercospecific intra/intermolecular H-bonding in (2,4)-cis-4S-aminoproline in contrast to (2,4)-trans-4R-aminoproline oligomers.

ZnO-beta zeolite: as an effective and eco-friendly heterogeneous catalyst for the synthesis of benzothiazole derivatives - Katkar, Santosh S.; Mohite, Pravinkumar H.; Gadekar, Lakshman S.; Vidhate, Kaluram N.; Lande, Machhindra K. (Chinese Chemical Letters, 2010)
A cheap and recyclable ZnO-beta zeolite was used as catalyst for the synthesis of benzothiazole derivatives. This method provides several advantages such as environmental friendliness, short reaction times, high yields, simple work-up procedure and catalyst was successfully reused for four cycles without significant loss of activity. (C) 2009 Machhindra K. Lande. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
Keywords: Benzothiazole; cyclocondensation; heterogeneous catalyst; ZnO-beta zeolite

ZnO-beta zeolite: as an effective and reusable heterogeneous catalyst for the one-pot synthesis of polyhydroquinolines - Katkar, Santosh S.; Mohite, Pravinkumar H.; Gadekar, Lakshman S.; Arbad, Balasaheb R.; Lande, Machhindra K. (Green Chemistry Letters and Reviews, 2010)
ZnO-beta zeolite, an inexpensive and mild catalyst, has been used for the synthesis of polyhydroquinolines in excellent yields from the one-pot four-component condensation of aldehydes, dimedone, ethyl acetoacetate, and ammonium acetate in ethanol at room temperature. The remarkable advantages offered by this method are a green catalyst, mild reaction conditions, simple work-up procedures, much faster reactions, and excellent yield of products. Furthermore, the catalyst could be reused several times keeping its initial activity in recycled reactions.
Keywords: Hantzsch condensation; heterogeneous catalyst; multicomponent; ZnO-beta zeolite

ZnO-beta zeolite mediated simple and efficient method for the one-pot synthesis of quinoxaline derivatives at room temperature - Katkar, Santosh S.; Mohite, Pravinkumar H.; Gadekar, Lakshman S.; Arbad, Balasaheb R.; Lande, Machhindra K. (Central European Journal of Chemistry, 2010)
A rapid and an efficient one-pot method for the synthesis of quinoxalines catalysed by ZnO-beta zeolite at room temperature is described. This environmentally benign method provides several advantages over methods that are currently employed such as a simple work-up, mild reaction conditions, good to excellent yields, and a process to recover and reuse the catalyst for several cycles with consistent activity.
Keywords: cyclocondensation; Quinoxaline; Room temperature; ZnO-beta zeolite

Antioxidant and anticancer activities of supramolecularly controlled magnetostructural halo-oximes of lawsone - Zaware, Santosh B.; Gonnade, Rajesh G.; Srinivas, Darbha; Khan, Ayesha A.; Rane, Sandhya Y. (New Journal of Chemistry, 2011)
Crystal engineering based on halogen bonding together with host-guest interactions of water molecules via H-bonding, stabilizing supramolecular architecture in chloro 1, bromo 2 and iodo 3 oximes of lawsone, is discussed. 1 and 2 crystallize in orthorhombic, non-centrosymmetric space group Pna2(1) while 3 crystallizes in monoclinic P2(1)/n space group. Non-covalent competitive interactions of asymmetric solvation and halogen bonding can have a large influence on the spin distribution in 1, 2 and 3 derivatives of spin carrier lawsone live polymer as revealed by single crystal X-ray and EPR studies. The significant C3-Cl/Br center dot center dot center dot O, C3-Cl/Br center dot center dot center dot H, O-H center dot center dot center dot O-C, C-H center dot center dot center dot pi and pi center dot center dot center dot pi interactions have been identified in the molecular assemblies leading to net magnetostructures of halo-oximes. Dimer-of-dimer-type tetrameric radical assembly of 3 and interacting bi- and monoradical chain on 2(1) axis in 1 and 2 have been identified. The proton-coupled electron transfers possibly govern the antioxidant nature in halooximes of spin carrier lawsone in terms of oxygen reduction to water molecules. Such activity is found to be directly proportional to the spin (radical) concentrations in 1 to 3 and increases in order 1 < 2 < 3 according to halogen bonding effect. The antioxidant chemical DPPH assays for scavenging of such free radicals result in similar trend of increasing order like 1 < 2 < 3, but the chemical in vitro as well as ex vivo SOD antioxidant activities and biological anticancer activity on MCF-7, Hela and HL-60 cell lines show the increasing order 3 < 2 < 1 according to H-bonding effect. This probably could be attributed to the conversion of superoxide radical ions into H(2)O(2), which leads to greater oxidative stress leading to apoptosis.

Assimilatory potential of helicoverpa armigera reared on host (chickpea) and nonhost (cassia tora) diets - Dawkar, Vishal V.; Chikate, Yojana R.; Gupta, Vidya S.; Slade, Susan E.; Giri, Ashok P. (Journal of Proteome Research, 2011)
Adaptation to plant allelochemicals is a crucial aspect of herbivore chemical ecology. To understand an insect ecology, we studied an effect of nonhost Cassia tora seed-based diet (Ct) on growth, development, and molecular responses in Helicoverpa armigera. We employed a comparative approach to investigate the proteomic differences in gut, hemolymph, and frass of H. armigera reared on a normal (chickpea seed-based, Cp) and Ct diet. In this study, a total of 46 proteins were identified by nano-LC-MS(E). Among them, 17 proteins were up-regulated and 29 proteins were down-regulated when larvae were exposed to the Ct diet. Database searches combined with GO analysis revealed that gut proteases engrossed in digestion, proteins crucial for immunity, adaptive responses to stress, and detoxification were down-regulated in the Ct fed larvae. Proteins identified in H. armigera hemolymph were found to be involved in defense mechanisms. Moreover, proteins found in frass of the Ct fed larvae were observed to participate in energy metabolism. Biochemical and quantitative real-time PCR analysis of selected candidate proteins showed differential gene expression patterns and corroborated with the proteomic data. Our results suggest that the Ct diet could alter expression of proteins related to digestion, absorption of nutrients, adaptation, defense mechanisms, and energy metabolism in H. armigera.
Keywords: adaptation; Cassia tora; Gene expression; Helicoverpa armigera; proteomics

Atomic level description of the domain closure in a dimeric enzyme: thermus thermophilus 3-isopropylmalate dehydrogenase - Graczer, Eva; Merli, Angelo; Singh, Rajesh Kumar; Karuppasamy, Manikandan; Zavodszky, Peter; Weiss, Manfred S.; Vas, Maria (Molecular Biosystems, 2011)
The domain closure associated with the catalytic cycle is described at an atomic level, based on pairwise comparison of the X-ray structures of homodimeric Thermus thermophilus isopropylmalate dehydrogenase (IPMDH), and on their detailed molecular graphical analysis. The structures of the apo-form without substrate and in complex with the divalent metal-ion to 1.8 angstrom resolution, in complexes with both Mn(2+) and 3-isopropylmalate (IPM), as well as with both Mn(2+) and NADH, were determined at resolutions ranging from 2.0 to 2.5 angstrom. Single crystal microspectrophotometric measurements demonstrated the presence of a functionally competent protein conformation in the crystal grown in the presence of Mn(2+) and IPM. Structural comparison of the various complexes clearly revealed the relative movement of the two domains within each subunit and allowed the identification of two hinges at the interdomain region: hinge 1 between alpha d and beta F as well as hinge 2 between alpha h and beta E. A detailed analysis of the atomic contacts of the conserved amino acid side-chains suggests a possible operational mechanism of these molecular hinges upon the action of the substrates. The interactions of the protein with Mn(2+) and IPM are mainly responsible for the domain closure: upon binding into the cleft of the interdomain region, the substrate IPM induces a relative movement of the secondary structural elements beta E, beta F, beta G, alpha d and alpha h. A further special feature of the conformational change is the movement of the loop bearing the amino acid Tyr139 that precedes the interacting arm of the subunit. The tyrosyl ring rotates and moves by at least 5 angstrom upon IPM-binding. Thereby, new hydrophobic interactions are formed above the buried isopropyl-group of IPM. Domain closure is then completed only through subunit interactions: a loop of one subunit that is inserted into the interdomain cavity of the other subunit extends the area with the hydrophobic interactions, providing an example of the cooperativity between interdomain and intersubunit interactions.

Atomic level description of the domain closure in a dimeric enzyme: thermus thermophilus 3-isopropylmalate dehydrogenase (IPMDH) - Graczer, E.; Merli, Angelo; Singh, R. K.; Karuppasamy, Manikandan; Zavodszky, P.; Weiss, M. S.; Vas, M. (FEBS Journal, 2011)
36th FEBS Congress of the Biochemistry for Tomorrows Medicine, Torino, ITALY, JUN 25-30, 2011

Auxin signaling and transport promote susceptibility to the root-infecting fungal pathogen fusarium oxysporum in arabidopsis - Kidd, Brendan N.; Kadoo, Narendra Y.; Dombrecht, Bruno; Tekeoglu, Muecella; Gardiner, Donald M.; Thatcher, Louise F.; Aitken, Elizabeth A. B.; Schenk, Peer M.; Manners, John M.; Kazan, Kemal (Molecular Plant-Microbe Interactions, 2011)

Azide derivatized anticancer agents of vitamin K-3: X-ray structural, DSC, resonance spectral and API studies - Badave, Kirti D.; Patil, Yogesh; Gonnade, Rajesh G.; Srinivas, Darbha; Dasgupta, Rajan; Khan, Ayesha A.; Rane, Sandhya (Journal of Molecular Structure, 2011)
Compound 1 [1-imino (acetyl hydrazino)-Vitamin K-3], displays valence tautomerically related electronic isomers as Form land Form II. Form I exhibits 2D packing fragment with 1D ribbon chains of N-H center dot center dot center dot O hydrogen bonds and shows EPR silent features. While Form II is EPR active and exhibits biradical nature with double quantum transitions at g = 2.0040. H-1 NMR of compound 2, [1-imino (hydrazino carboxylate)-Vitamin K-3] and Form II exhibit pi delocalization via resonance assisted H-bonding [RAHB] effect compared to Form I. Molecular interactions in Form I and II are visualized by DSC. The electronic structures of compounds 1 and 2 have been correlated to their API values by measuring anticancer activities, mitochondrial potentials and DNA shearing patterns. Form II and compound 2 indicate mitochondria mediated apoptosis (similar to 75% cell death) while Form I causes 35% cell death. (C) 2011 Elsevier B.V. All rights reserved.
Keywords: Anticancer agents; API (Active Pharmaceutical Ingredients); Electronic isomers; RAHB (resonance assisted H-bonding); Vitamin K-3

Biochemical characterisation of alpha-amylase inhibitors from achyranthes aspera and their interactions with digestive amylases of coleopteran and lepidopteran insects - Hivrale, Vandana K.; Chougule, Nanasaheb P.; Giri, Ashok P.; Chhabda, Pavan J.; Kachole, Andmanvendra S. (Journal of the Science of Food and Agriculture, 2011)
BACKGROUND: Starchy seeds are an important food and a source of dietary ingredients in many countries. However, they suffer from extensive predation by bruchids (weevils) and other pests. alpha-Amylase inhibitors are attractive candidates for the control of seed weevils, as these insects are highly dependent on starch as an energy source. RESULTS: A proteinaceous alpha-amylase inhibitor from the seeds of Achyranthes aspera was identified, purified and characterised. In electrophoretic analysis, two prominent amylase inhibitor activity bands (AI1 and AI2) were detected. The inhibitor was purified 9.99-fold with 1206.95 total amylase inhibitor units mg(-1) protein. The molecular weight of the purified inhibitor was around 6 kDa. The isolated alpha-amylase inhibitor was found to be resistant to heat and proteolysis. Feeding analysis of Callosobruchus maculatus larvae on a diet containing seed powder of A. aspera revealed that survival of the larvae was severely affected, with the highest mortality rate occurring on the fifth day of feeding. The isolated inhibitor inhibited the majority of amylase isoforms of C. maculatus, Tribolium confusum and Helicoverpa armigera in electrophoretic analysis and solution assays. CONCLUSION: The information obtained in the present investigation could be useful for a genetic engineering approach that would make seeds resistant to storage pest infestations. (C) 2011 Society of Chemical Industry
Keywords: Achyranthes aspera; Amylase inhibitors; amylases; Callosobruchus maculatus; Tribolium confusum

Bioresponsive mesoporous silica nanoparticles for triggered drug release - Singh, Neetu; Karambelkar, Amrita; Gu, Luo; Lin, Kevin; Miller, Jordan S.; Chen, Christopher S.; Sailor, Michael J.; Bhatia, Sangeeta N. (Journal of the Americal Chemical Society, 2011)

Borazine as a sensor for fluoride ion: a computational and experimental study - Kesharwani, Manoj K.; Suresh, Moorthy; Das, Amitava; Ganguly, Bishwajit (Tetrahedron Letters, 2011)
The computational and experimental studies have revealed that even simple molecule like borazine can act as a sensor for fluoride ions. This study further reported the various binding modes of analytes using quantum chemical calculations and the nature of such interactions have been examined using electron density surface analysis. Total charge transfer analysis (qCT) correlates well with the binding affinities of analytes with the borazine receptor.

Catalytic dehydroaromatization of n-alkanes by pincer-ligated iridium complexes - Ahuja, Ritu; Punji, Benudhar; Findlater, Michael; Supplee, Carolyn; Schinski, William; Brookhart, Maurice; Goldman, Alan S. (Nature Chemistry, 2011)
Aromatic hydrocarbons are among the most important building blocks in the chemical industry. Benzene, toluene and xylenes are obtained from the high temperature thermolysis of alkanes. Higher alkylaromatics are generally derived from arene–olefin coupling, which gives branched products—that is, secondary alkyl arenes—with olefins higher than ethylene. The dehydrogenation of acyclic alkanes to give alkylaromatics can be achieved using heterogeneous catalysts at high temperatures, but with low yields and low selectivity. We present here the first catalytic conversion of n-alkanes to alkylaromatics using homogeneous or molecular catalysts—specifically ‘pincer’-ligated iridium complexes—and olefinic hydrogen acceptors. For example, the reaction of n-octane affords up to 86% yield of aromatic product, primarily o-xylene and secondarily ethylbenzene. In the case of n-decane and n-dodecane, the resulting alkylarenes are exclusively unbranched (that is, n-alkyl-substituted), with selectivity for the corresponding o-(n-alkyl)toluene.

Ceria-zirconia mixed oxides as thermal resistant catalysts for the decomposition of nitrous oxide at high temperature - Esteves, P.; Wu, Y.; Dujardin, Christophe; Dongare, Mohan K.; Granger, P. (Catalysis Today, 2011)
This present study deals with the development of thermally stable catalysts for the decomposition of nitrous oxide. There is actually a growing interest to minimise the emissions of nitrous oxide (N(2)O) as side-product from nitric acid plants due to a global warming potential of approximately 300 times higher than that of CO(2). Different strategies have already been implemented at industrial scale but they are still suffering from significant drawbacks essentially associated to a poor selectivity and sometimes a short lifetime in particular when the catalytic process is inserted downstream the ammonia burner. In those critical conditions, with high residual temperature of similar to 900 degrees C, significant surface and bulk reconstructions take place and then lead to drastic losses of specific surface area and related catalytic performances in the decomposition of N(2)O to N(2). Previous investigations performed in our laboratory revealed the potentiality of zirconia particularly after yttria incorporation [Appl. Catal. B 62 (2005) 236]. Novel developments of more stable ceria-zirconia based catalysts are reported in this study. Further stabilisation and enhancement in activity have been discussed on the basis of oxygen mobility related to structural properties. (C) 2010 Elsevier B.V. All rights reserved.
2nd International Symposium on Air Pollution Abatement Catalysis (APAC), Cracow, POLAND, SEP 08-11, 2011
Keywords: Ceria-zirconia based catalysts; Greenhouse gas; N(2)O catalytic decomposition; Nitric acid plant; Nitrous oxide

Chromatographic separations of zinc, iron and copper metal ions through cellulose poroussolid fiber supported solid membrane in mixedsolvent systems - Gaikwad, Abaji G. (Chemical Engineering Communications, 2011)
An interesting aspect of chromatographic separation of zinc, iron, and copper metal ions through a cellulose porous solid fiber supported solid membrane from source solution to receiving phase has been explored in mixed solvent systems. The cellulose porous solid fiber supported solid membrane was prepared by chemically immobilizing tartaric acid. The experimental variables explored were concentration of copper, zinc, and iron metal ions, hydrochloric acid, composition of mixed solvents, and stirring speed. The efficiency of a cellulose porous solid fiber supported solid membrane system has been evaluated for the separation of metal ions. The pre-concentration of metal ions was carried out from the dilute solutions. The two-channel chromatographic cellulose porous solid fiber supported solid membrane system has been investigated for the transport of metal ions from the source solution to receiving phase. The capillary action phenomenon in the cellulose micro fibers plays a significant and active role in the transport of ions through the cellulose porous solid fiber supported solid membrane in mixed solvents.
Keywords: and iron ions: Single- and double-channel membrane system; Cellulose porous solid fiber supported solid membrane; Copper; zinc

Combined strategy for the dispersion/dissolution of single walled carbon nanotubes and cellulose in water - Adsul, Mukund G.; Rey, Diego A.; Gokhale, Digambar V. (Journal of Materials Chemistry, 2011)
Co-dispersion of native cellulose and single walled carbon nanotubes in water is demonstrated. The pH of the water should be between 6 and 10 for better dispersion. Raman spectra confirm debundling of nanotubes in water and FTIR spectra reveal that the co-solubility is likely caused through disruption of intramolecular hydrogen bonds in the cellulose by hydroxyl groups present on nanotubes surface and the creation of intermolecular hydrogen bonds between cellulose and carbon nanotubes. This is a very simple method for co-dispersion/dissolution of nanotubes and cellulose in water without covalent modifications and expands the repertoire of nanotube modification strategies that are amenable to biological applications.

Comparative genomics of the pathogenic ciliate Ichthyophthirius multifiliis, its free-living relatives and a host species provide insights into adoption of a parasitic lifestyle and prospects for disease control - Coyne, Robert S.; Hannick, Linda; Shanmugam, Dhanasekaran; Hostetler, Jessica B.; Brami, Daniel; Joardar, Vinita S.; Johnson, Justin; Radune, Diana; Singh, Irtisha; Badger, Jonathan H.; Kumar, Ujjwal; Saier, Milton; et al. (Genome Biology, 2011)
Background: Ichthyophthirius multifiliis, commonly known as Ich, is a highly pathogenic ciliate responsible for 'white spot', a disease causing significant economic losses to the global aquaculture industry. Options for disease control are extremely limited, and Ich's obligate parasitic lifestyle makes experimental studies challenging. Unlike most well-studied protozoan parasites, Ich belongs to a phylum composed primarily of free-living members. Indeed, it is closely related to the model organism Tetrahymena thermophila. Genomic studies represent a promising strategy to reduce the impact of this disease and to understand the evolutionary transition to parasitism. Results: We report the sequencing, assembly and annotation of the Ich macronuclear genome. Compared with its free-living relative T. thermophila, the Ich genome is reduced approximately two-fold in length and gene density and three-fold in gene content. We analyzed in detail several gene classes with diverse functions in behavior, cellular function and host immunogenicity, including protein kinases, membrane transporters, proteases, surface antigens and cytoskeletal components and regulators. We also mapped by orthology Ich's metabolic pathways in comparison with other ciliates and a potential host organism, the zebrafish Danio rerio. Conclusions: Knowledge of the complete protein-coding and metabolic potential of Ich opens avenues for rational testing of therapeutic drugs that target functions essential to this parasite but not to its fish hosts. Also, a catalog of surface protein-encoding genes will facilitate development of more effective vaccines. The potential to use T. thermophila as a surrogate model offers promise toward controlling 'white spot' disease and understanding the adaptation to a parasitic lifestyle.

Comparative production of cellulases by mutants of penicillium janthinellum NCIM 1171 and its application in hydrolysis of avicel and cellulose - Singhvi, M. S.; Adsul, Mukund G.; Gokhale, D. V. (Bioresource Technology, 2011)
Mutants of Penicillium janthinellum NCIM 1171 were evaluated for cellulase production using both submerged fermentation (SmF) and solid state fermentation (SSF). Mutant EU2D-21 gave highest yields of cellulases in both SmF and SSF. Hydrolysis of Avicel and cellulose were compared using SmF and SSF derived enzyme preparations obtained from EU2D-21. Surprisingly, the use of SSF derived preparation gave less hydrolysis compared to SmF derived enzymes. This may be due to inactivation of beta-glucosidase at 50 degrees C in SSF derived enzyme preparations. SmF derived enzyme preparations contained both thermostable and thermosensitive beta-glucosidases where as SSF derived enzyme preparations contained predominantly thermosensitive beta-glucosidase. This is the first report on less thermostability of SSF derived p-glucosidase which is the main reason for getting less hydrolysis. (C) 2011 Elsevier Ltd. All rights reserved.
Keywords: beta-Glucosidase thermostability; Mutant EU2D-21; Solid state fermentation; Submerged fermentation

Comparative study of porphyrin derivatives in monolayers at the air-water interface and in langmuir-blodgett films - Ghosh, Amrita; Mahato, Prasenjit; Choudhury, Sipra; Das, Amitava (Thin Solid Films, 2011)
The orientation and aggregation of various porphyrin derivatives at the air–water interface and in Langmuir–Blodgett films were investigated. Monolayer properties of these molecules, where long alkyl chain(s) were covalently bound through different functionality of varying hydrophilicity were studied by measuring surface pressure area isotherms. Such derivatives, where ether functionality (functionalities) was (were) used for linking long alkyl chain(s), did not form uniform monolayer; instead they were found to form multilayer clusters or aggregates on the water surface. On the other hand, porphyrin derivative functionalized at the four peripheral phenyl rings with eight hexadecyl ether chains formed stable spherical vesicles when deposited on mica. Tetra N-alkyl pyridinium porphyrins with long alkyl chain were found to form various phases on the water surface. Evidence of transition from horizontal orientation to vertical orientation of porphyrin rings of porphyrin molecules having C14 chains was observed. This type of transition was lost with the porphyrin molecule with a relatively smaller chain (C8).

Competitive binding of Ba2+and Sr2+ to 18-crown-6 in a receptor with a 1-methoxyanthraquinone analogue as the other binding site - Banerjee, Tanmay; Suresh, Moorthy; Ghosh, Hirendra N.; Das, Amitava (Europian Journal of Inorganic Chemistry, 2011)
Owing to their immense biological significance, development of sensors for the selective detection of alkaline earth metal ions has attracted vast research interest. In this article we have reported the synthesis, characterisation and ion binding studies of a new RuII-polypyridyl-crown-anthraquinone complex (5). Studies confirm selective binding of BaII, SrII and CaII ions, with Kmath image > Kmath image >> Kmath image, over all other metal ions, to the crown ether moiety and not to the methoxy anthraquinone component, the latter being the second binding site available and known for its affinity towards alkaline earth metal ions from one of our previous reports.

Concurrent display of both alpha- and beta-turns in a model peptide - Srinivas, Deekonda; Vijayadas, Kuruppanthara N.; Gonnade, Rajesh G.; Phalgune, Usha D.; Rajamohanan, Pattuparambil R.; Sanjayan, Gangadhar J. (Organic & Biomolecular Chemistry, 2011)
This article describes a model peptide that concurrently displays both alpha- and beta-turns, as demonstrated by structural investigations using single crystal X-ray crystallography and solution-state NMR studies. The motif reported herein has the potential for the design of novel conformationally ordered synthetic oligomers with structural architectures distinct from those classically observed.

Conformational transitions in ariesaema curvatum lectin: characterization of an acid induced active molten globule - Sharma, Urvashi; Gaikwad, Sushama M.; Suresh, C. G.; Dhuna, Vikram; Singh, Jatinder; Kamboj, Sukhdev Singh (Journal of Fluorescence, 2011)
Biophysical characterization of a lectin from Ariesaema curvatum (ACL) was carried out using steady state as well as time resolved fluorescence and CD spectroscopy under various denaturing conditions. An intermediate with altered tryptophan microenvironment was detected in the phase diagram, which exibited pronounced secondary structure and hemagglutinating activity in presence of 0.25 M Gdn-HCl. An acid induced molten- globule like structure possessing activity and higher thermostability was detected. Transition to the molten globule state was reversible in nature. The lectin retained hemagglutinating activity even after incubation at 95 A degrees C. Both chemical and thermal unfolding of the lectin were found to consist of multistate processes. Fluorescence quenching of ACL was strong with acrylamide and KI. The single tryptophan was found to be surrounded by high density of the positively charged amino acid residues as shown by a ten fold higher K(sv) for KI compared to that for CsCl. The average lifetime of tryptophan fluorescence increased from 1.24 ns in the native state to 1.72 ns in the denatured state.
Keywords: Araceae; Fluorescence lifetime; Hemagglutinin; Molten globule; Secondary structure; Thermostability; Unfolding

Conformationally rigid aromatic amino acids as potential building blocks for abiotic foldamers - Ramesh, Veera V. E.; Roy, Arup; Vijayadas, Kuruppanthara N.; Kendhale, Amol M.; Prabhakaran, Panchami; Gonnade, Rajesh G.; Puranik, Vedavati G.; Sanjayan, Gangadhar J. (Organic & Biomolecular Chemistry, 2011)
This communication describes the development of conformationally constrained unnatural aromatic amino acids, constructed on rigid backbone wherein the carboxyl and amino groups project in two dimensions (planes) on the aromatic framework. Such a feature offers the possibility of design and development of conformationally ordered synthetic oligomers with intriguing structural architectures distinct from those classically observed. Furthermore, such amino acids will have the potential to extend the conformational space available for foldamer design with diverse backbone conformation and structural architectures.

Construction of the 5,10b-phenanthridine skeleton using [3+2]-cycloaddition of a non-stabilized azomethine ylide: total synthesis of (+/-)-maritidine and (+/-)-crinine alkaloids - Pandey, Ganesh; Gupta, Nishant R.; Gadre, Smita R. (European Journal of Organic Chemistry, 2011)
Vicinal quaternary and tertiary stereocenters of the 5,10b-phenanthridine skeleton 1 are constructed simultaneously in one step by the [3+2]-cycloaddition of non-stabilized azomethine ylide 9, generated by sequential double desilylation of 10 utilizing silver(I) fluoride as a one-electron oxidant. The regioas well as stereochemical origin of this cycloaddition reaction is explained through a favorable transition state 9''. The strategy is successfully applied for the total synthesis of the biologically active alkaloids (+/-)-maritidine (1a), (+/-)-crinine (1b), and their analogues (1d, 1e, and 1f).
Keywords: alkaloids; Azomethine ylides; Cycloaddition; Natural products; Ylides

Control of competing hydrogenation of phenylhydroxylamine to aniline in a single-step hydrogenation of nitrobenzene to p-aminophenol - Nadgeri, Jayprakash M.; Biradar, Narayan S.; Patil, Priyanka B.; Jadkar, Sachin T.; Garade, Ajit C.; Rode, Chandrashekhar V. (Industrial & Engineering Chemistry Research, 2011)
Two steps involving catalytic hydrogenation of nitrobenzene to phenylhydroxylamine (PHA) in acid medium and its rearrangement to p-aminophenol (PAP) were studied separately in a batch reactor, using a well-characterized 3% Pt/C catalyst. The first step of hydrogenation of nitrobenzene to PHA could be carried out at 303 K and a H(2) pressure of 0.69 MPa with complete conversion of nitrobenzene, while the achieved selectivity to PHA was higher than 90% with some formation of aniline, even at lower temperature. The second step of PHA rearrangement to PAP could be achieved under a hydrogen atmosphere at elevated temperature of 353 K to give a maximum selectivity to PAP of 74%.

Correction to what drives the redox properties of model green fluorescence protein chromophores? - Solntsev, Kyril M.; Ghosh, Debashree; Amador, Adrian; Josowicz, Mira; Krylov, Anna I. (Journal of Physical Chemistry Letters, 2011)
We report the first experimental determination of the oxidation potentials E-ox(0). (relative to the standard hydrogen electrode, SHE) of model green fluorescent protein (GFP) chromophores. Para-, meta, and ortho-hydroxy (4-hydroxybenzylidene-2,3-dimethylimidazolinone, HBDI) and methoxy (MeOBDI) derivatives were studied. E-ox(0) of the three isomers in acetonitrile are -1.31, -1.52, and -1.39 V, respectively. Electronic structure calculations reproduce the observed differences between the isomers and reveal that E-ox(0) follows the ionization energies (IEs), that is, p-MeOBDI has the lowest IE (6.96 eV in the gas phase) due to resonance stabilization of its cation, whereas the resonance is detuned in m-MeOBDL resulting in more-negative E-ox(0). The observed meta and ortho effects in E-ox(0) are similar to the trends in pK(a). The effect of increased solvent polarity on absolute.E-ox(0) (and especially on para-meta-ortho differences) was found to be small. The redox properties of GFP chromophores are driven by their structure and can be correlated with IEs, which can be exploited in predicting the properties of other fluorescent protein chromophores.

Cyclodiphosph(III)azane chemistry – ylides from the reaction of [(RNH)P-N(t-Bu)]2 [R = t-Bu, i-Pr] with dimethyl maleate and chiral ansa-type derivatives from reaction of [ClP-N(t-Bu)]2 with a substituted BINOL - Swamy, K.C. Kumara; Gangadhararao, G.; Srinivas, Venu; Kumar, N. N. Bhuvan; Balaraman, Ekambaram; Chakravarty, Manab (Inorganica Chimica Acta, 2011)
Use of a simple inorganic ring system with the cyclodiphosph(III)azane skeleton [e.g. [(RNH)P-N(t-Bu)]2 [R = t-Bu (7), i-Pr (8)] to probe some of the intermediates proposed in phosphine mediated organic reactions is highlighted. Thus the reaction of 7–8 with the allenylphosphine oxide Ph2P(O)C(Ph)double bond; length as m-dashCdouble bond; length as m-dashCH2 (9) affords the phosphinimines [(RNH)P(μ-N-t-Bu)2P(double bond; length as m-dashN-R)-C(double bond; length as m-dashCH2)CH(Ph)-P(O)Ph2] [R = t-Bu (10), i-Pr (11)], while a similar reaction of 7–8 with dimethyl maleate (or dimethyl fumarate) affords the ylides [(RNH)P(μ-N-t-Bu)2P(NH-R)double bond; length as m-dashC(CO2Me)-CH2(CO2Me) [R = t-Bu (18), i-Pr (19)]. The implication of such reactions on phosphine mediated organic transformations including Morita–Baylis–Hillman reaction is mentioned. In a rather rare type of situation, an unusually long phosphoryl (Pdouble bond; length as m-dashO) bond [1.538 (5) Å] as revealed the X-ray structure of {(R)-6,6′-(t-Bu)2-1,1′-(C10H5)2-2,2′-O2-}{P(O)(N-t-Bu)2-P(Se)} (27) is rationalized by means of crystallographic disorder in packing after comparing the data with that in the literature and {1,1′-(C10H6)2-2,2′-O2}{P(Se)(N-t-Bu)2-P(Se)} (29). X-ray structures of the new compounds 10–11, 18–19, 27 and 29 are discussed. Compound 10 crystallizes in the chiral space group Pca2(1) with (S)-chirality at the carbon center [–C(double bond; length as m-dashCH2)CH(Ph)-P] suggesting a case of spontaneous resolution through crystallization.

Degradation of methylene blue via photocatalysis of transition metal-loaded sulfated TiO2 - Gambhire, A. B.; Lande, Machhindra K.; Arbad, B. R.; Rathod, S. B.; Gholap, Ramkrishna S.; Patil, K. R. (Materials Chemistry and Physics, 2011)
Transition metal-loaded nanocrystalline SO42-/TiO2 powders were prepared by sol-gel method. Anatase is found as the active phase in all the samples. Sulfation process clearly stabilizes TiO2 catalyst phase against sintering, maintaining anatase phase and relatively high surface area values with respect to pure TiO2. Wide structural and surface characterization of samples was carried out in order to establish a correlation between the effect of sulfation and metal incorporation on the TiO2 photocatalytic properties. The maximum photocatalytic decomposition of methylene blue solution was achieved with sulfation of TiO2. In addition, incorporation of metal into the structure of SO42-/TiO2 seems to enhance the photocatalytic activity of the samples, which is ascribed to the enlargement of specific surface area, photogenerated carriers separation, light absorption, as well as the higher surface acidity. (C) 2010 Elsevier B.V. All rights reserved.
Keywords: nanomaterial; Photocatalytic activity; sol-gel process

Development of biocatalysts for production of commodity chemicals from lignocellulosic biomass - Adsul, Mukund G.; Singhvi, M. S.; Gaikaiwari, Shalaka A.; Gokhale, D. V. (Bioresource Technology, 2011)
Lignocellulosic biomass is recognized as potential sustainable source for production of power, biofuels and variety of commodity chemicals which would potentially add economic value to biomass. Recalcitrance nature of biomass is largely responsible for the high cost of its conversion. Therefore, it is necessary to introduce some cost effective pretreatment processes to make the biomass polysaccharides easily amenable to enzymatic attack to release mixed fermentable sugars. Advancement in systemic biology can provide new tools for the development of such biocatalysts for sustainable production of commodity chemicals from biomass. Integration of functional genomics and system biology approaches may generate efficient microbial systems with new metabolic routes for production of commodity chemicals. This paper provides an overview of the challenges that are faced by the processes converting lignocellulosic biomass to commodity chemicals. The critical factors involved in engineering new microbial biocatalysts are also discussed with more emphasis on commodity chemicals. (C) 2011 Elsevier Ltd. All rights reserved.
Keywords: Biomass utilization; Commodity chemicals; Ethanol; Lactic acid; Microbial cellulases

Development of non-woven nanofibers of egg albumen-poly (vinyl alcohol) blends: influence of solution properties on morphology of nanofibers - Rathna, Gundloori Venkata Naga; Jog, Jyoti Prakash; Gaikwad, A. B. (Polymer Journal, 2011)
Egg albumen (EA), a highly functional globular protein with desirable properties, is the least-explored material for biomaterial applications, although it is available in abundance. In our studies, we explored the viability of EA and various blends with biocompatible and non-toxic poly (vinyl alcohol) (PVA) to produce nanofibers for biomedical applications. EA and PVA blends were prepared in various compositions. Electrospinning was used to fabricate non-woven nanofibers. Solution properties, such as viscosity and electrical conductivity, were evaluated for various prepared solutions. Solution viscosity increased with increasing polymer concentration. Solutions with higher contents of EA recorded increased conductivity, which decreased with increasing PVA content. The influence of solution properties on the morphological appearance of as-spun products was studied using scanning electron microscopy. Instead of nanofibers, nanoparticles and microparticles of EA were produced at even higher contents. In contrast, a gradual increase in the addition of PVA content to 8% EA solution resulted in the transformation of particles from large agglomerates to very fine fibers (approximate to 100nm in diameter) because of the influence of polymer content, viscosity and conductivity. The polymer-polymer interactions in the prepared materials have been validated by Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction and gel electrophoresis. Polymer Journal (2011) 43, 654-661; doi:10.1038/pj.2011.34; published online 18 May 2011
Keywords: Biocompatibility; biodegradable; blends; nanotechnology; Proteins

Diamine derivative of a ruthenium(II)-polypyridyl complex for chemodosimetric detection of nitrite ion in aqueous solution - Ghosh, Amrita; Das, Priyadip; Saha, Sukdeb; Banerjee, Tanmay; Bhatt, Harshad B.; Das, Amitava (Inorganica Chimica Acta, 2011)
Nitrite is quite an abundant anion in the environment. It, however, becomes toxic to human life, as well as aquatic animals when present above the permissible concentration level. We have reported here a Ru(II)-polypyridyl-based complex (1) for chemodosimetric detection of nitrite ion in aqueous solution. Formation of the new triazole based complex, generated by reaction of 1 and N2O3, is ascertained by comparing its properties with a presynthesised triazole complex.

Dibutyl phthalate, a secondary metabolite from mimusops elengi - Ruikar, A. D.; Gadkari, T. V.; Phalgune, U. D.; Puranik, Vedavati G.; Deshpande, N. R. (Chemistry of Natural Compounds, 2011)

Differential induction, purification and characterization of cold active lipase from Yarrowia lipolytica NCIM 3639 - Yadav, K. N. Sathish; Adsul, Mukund G.; Bastawade, Kulbhushan B.; Jadhav, D. D.; Thulasiram, H. V.; Gokhale, D. V. (Bioresource Technology, 2011)
The production, purification and characterization of cold active lipases by Yarrowia lipolytica NCIM 3639 is described. The study presents a new finding of production of cell bound and extracellular lipase activities depending upon the substrate used for growth. The strain produced cell bound and extracellular lipase activity when grown on olive oil and Tween 80, respectively. The organism grew profusely at 20 degrees C and at initial pH of 5.5, producing maximum extracellular lipase. The purified lipase has a molecular mass of 400 kDa having 20 subunits forming a multimeric native protein. Further the enzyme displayed an optimum pH of 5.0 and optimum temperature of 25 degrees C. Peptide mass finger printing reveled that some peptides showed homologues sequence (42%) to Yarrowia lipolytica LIP8p. The studies on hydrolysis of racemic lavandulyl acetate revealed that extracellular and cell bound lipases show preference over the opposite antipodes of irregular monoterpene, lavandulyl acetate. (C) 2011 Elsevier Ltd. All rights reserved.
Keywords: Cell bound lipase; Cold active lipase; Extracellular lipase; Lavandulyl acetate; Oligomeric lipase

Effect of solvation on the vertical ionization energy of thymine: from microhydration to bulk - Ghosh, Debashree; Isayev, Olexandr; Slipchenko, Lyudmila V.; Krylov, Anna I. (Journal of Physical Chemistry A, 2011)
The effect of hydration on the vertical ionization energy (VIE) of thymine was characterized using equation-of-motion ionization potential coupled-cluster (EOM-IP-CCSD) and effective fragment potential (EFP) methods. We considered several microsolvated clusters as well as thymine solvated in bulk water. The VIE in bulk water was computed by averaging over solvent-solute configurations obtained from equilibrium molecular dynamics trajectories at 300 K. The effect of microsolvation was analyzed and contrasted against the combined effect of the first solvation shell in bulk water. Microsolvation reduces the ionization energy (IE) by about 0.1 eV per water molecule, while the first solvation shell increases the IE by 0.1 eV. The subsequent solvation lowers the IE, and the bulk value of the solvent-induced shift of thymine's VIE is approximately -0.9 eV. The combined effect of the first solvation shell was explained in terms of specific solute-solvent interactions, which were investigated using model structures. The convergence of LE to the bulk value requires the hydration sphere of approximately 13.5 angstrom radius. The performance of the EOM-IP-CCSD/EFP scheme was benchmarked against full EOM-IP-CCSD using microhydrated structures. The errors were found to be less than 0.01-0.02 eV. The relative importance of the polarization and higher multipole moments in EFP model was also investigated.

Efficient hydrogenation of organic carbonates, carbamates, and formates indicates alternative routes to methanol based on CO2 and CO - Balaraman, Ekambaram; Gunanathan, Chidambaram; Zhang, Jing; Shimon, Linda J. W.; Milstein, David (Nature Chemistry, 2011)
Catalytic hydrogenation of organic carbonates, carbamates and formates is of significant interest both conceptually and practically, because these compounds can be produced from CO2 and CO, and their mild hydrogenation can provide alternative, mild approaches to the indirect hydrogenation of CO2 and CO to methanol, an important fuel and synthetic building block. Here, we report for the first time catalytic hydrogenation of organic carbonates to alcohols, and carbamates to alcohols and amines. Unprecedented homogeneously catalysed hydrogenation of organic formates to methanol has also been accomplished. The reactions are efficiently catalysed by dearomatized PNN Ru(II) pincer complexes derived from pyridine- and bipyridine-based tridentate ligands. These atom-economical reactions proceed under neutral, homogeneous conditions, at mild temperatures and under mild hydrogen pressures, and can operate in the absence of solvent with no generation of waste, representing the ultimate ‘green’ reactions. A possible mechanism involves metal–ligand cooperation by aromatization–dearomatization of the heteroaromatic pincer core.

Efficient synthesis of benzofuranones: N-heterocyclic carbene (NHC)/base-catalyzed hydroacylation-stetter-rearrangement cascade - Padmanaban, Mohan; Biju, Akkattu T.; Glorius, Frank (Organic Letters, 2011)
A N-heterocyclic carbene/base-catalyzed cascade reaction leading to the formation of functionalized benzofuranones is reported. The reaction proceeds via an intramolecular hydroacylation of unactivated alkynes followed by an intermolecular Stetter reaction and a base-catalyzed chromanone to benzofuranone rearrangement.

Electrical behavior of silver particulate films deposited on 8 MeV electron beam irradiated softened polystyrene substrates - Pattabi, Manjunatha; Gurumurthy, S. C.; Sanjeev, Ganesh; Gaikwad, A. B. (Journal of Materials Science-Materials in Electronics, 2011)
Results of the investigations carried out on the electrical behavior of silver particulate films deposited on electron beam irradiated polystyrene (PS) coated substrates held at a temperature of 455 K in a vacuum of 8 x 10(-6) torr at a constant deposition rate of 0.4 nm/s are reported. It is known that when metals are evaporated on to softened polymer substrates, subsurface particulate structures are formed whose morphology is dependent on deposition parameters. Further, it was shown that the morphology is dependent on polymer-metal interaction. The present work demonstrates that the polymer-metal interaction can be brought about in inert polymers like PS by electron irradiation. The results indicate that the films deposited on PS irradiated to a dose of 20 and 25 kGy gives rise to smaller clusters with smaller inter-cluster separation, better suited for sensor applications. The induced polymer-metal interaction is attributed to the creation of free radicals due to the 8 MeV electron irradiation.

Enhanced enzymatic hydrolysis of cellulose by partial modification of its chemical structure - Shaikh, H. M.; Adsul, Mukund G.; Gokhale, D. V.; Varma, Anjanikumar (Carbohydrate Polymers, 2011)
A series of 2,3-dialdehyde celluloses with different degrees of oxidation were used for deriving corresponding dicarboxylate, dicarboxy, and Schiff's base cellulose derivatives. The dialdehyde cellulose was hydrolyzed by cellulase to a lower extent than the starting cellulose, except at high levels of aldehyde content (above 50%). For dicarboxylate and dicarboxy celluloses, the highest level of oxidized NaDCC and DCC hydrolysed up to 70 and 60% respectively which was 3-4 times more than cellulose. The 2,3-dioxime cellulose derivative hydrolyzes only up to 16.3% for the highest level of oxidized dioxime. In the case of 2,3-diethylimine cellulose, all derivatives hydrolyse faster than the native cellulose. Up to 75% hydrolysis was observed for 2,3-diethyimine cellulose-50, 2,3-dipropylimine and 2,3-dibutylimine cellulose. The 2,3-dibenzylimine cellulose hydrolyses a little slower than the alkylimine derivatives. The 2,3-dihydrazone cellulose derivatives with all level of oxidation showed resistance towards enzymatic hydrolysis. (C) 2011 Elsevier Ltd. All rights reserved.
Keywords: 2; 3-Dialdehyde celluloses; 3-Dibenzylimine cellulose; 3-Dibutylimine cellulose; 3-Dicarboxy celluloses; 3-Diethyimine cellulose; 3-Dihydrazone cellulose; 3-Dipropylimine cellulose; Cellulase; Enzymatic hydrolysis

Enhanced stability of G-quadruplexes from conformationally constrained aep-PNA backbone - Sharma, Nagendra K.; Ganesh, Krishna N. (Organic & Biomolecular Chemistry, 2011)
Nucleic (DNA) acids having contiguous stretch of G sequence form quadruplex structure, which is very critical to control cell division. Recently the existence of G-quadruplex in RNA is also reported in presence of monovalent metal ion. PNA is a promising DNA analogue which binds strongly to DNA to form PNA: DNA duplex or PNA(2) : DNA triplex. PNA also forms quadruplexes such G-quadruplex and i-motif in G and C-rich sequences respectively. aep-PNA containing a prolyl ring is one of several PNA analogues that provide rigidity and chirality in backbone and has binding affinity to natural DNA which is higher than that of PNA. Here we examine the ability of aep-PNA-G to form a quadruplex by UV, CD and mass spectroscopic techniques.

Exciton-coupled charge-transfer dynamics in a porphyrin J-aggregate/TiO 2 complex - Verma, Sandeep; Ghosh, Amrita; Das, Amitava; Ghosh, Hirendra Nath (Chemistry a European Journal, 2011)
Exciton-coupled charge-transfer (CT) dynamics in TiO2 nanoparticles (NP) sensitized with porphyrin J-aggregates has been studied by femtosecond time-resolved transient absorption spectroscopy. J-aggregates of 5,10,15-triphenyl-20-(3,4-dihydroxyphenyl) porphyrin (TPPcat) form CT complexes on TiO2 NP surfaces. Catechol-mediated strong CT coupling between J-aggregate and TiO2 NP facilitates interfacial exciton dissociation for electron injection into the conduction band of the TiO2 nanoparticle in pulse width limited time (<80 fs). Here, the electron-transfer (<80 fs) process dominates over the intrinsic exciton-relaxation process (J-aggregates: ca. 200 fs) on account of exciton-coupled CT interaction. The parent hole on J-aggregates is delocalized through J-aggregate excitonic coherence. As a result, holes immobilized on J-aggregates are spatially less accessible to electrons injected into TiO2, and thus the back electron transfer (BET) process is slower than that of the monomer/TiO2 system. The J-aggregate/porphyrin system shows exciton spectral and temporal properties for better charge separation in strongly coupled composite systems.

Expression analysis of cinnamoyl-CoA reductase (CCR) gene in developing seedlings of Leucaena leucocephala: A pulp yielding tree species - Srivastava, Sameer; Gupta, Ranadheer K.; Arha, Manish; Vishwakarma, Rishi K.; Rawal, Shuban K.; Kishor, P. B. Kavi; Khan, Bashir Mohammad (Plant Physiology and Biochemistry, 2011)
Removal of lignin is a major hurdle for obtaining good quality pulp. Leucaena leucocephala (subabul) is extensively used in paper industry in India; therefore, as a first step to generate transgenic plants with low lignin content, cDNA and genomic clones of CCR gene were isolated and characterized. The cDNA encoding CCR (EC 1.2.1.44) was designated as LI-CCR; the sequence analysis revealed an Open Reading Frame (ORF) of 1005 bp. Phylogenetic analysis showed that LI-CCR sequence is highly homologous to CCRs from other dicot plants. The 2992 bp genomic clone of Leucaena CCR consists of 5 exons and 4 introns. The haploid genome of L leucocephala contains two copies as revealed by DNA blot hybridization. LI-CCR gene was over-expressed in Escherichia coli, which showed a molecular mass of approximately 38 kDa. Protein blot analysis revealed that LI-CCR protein is expressed at higher levels in root and in stem, but undetectable in leaf tissues. Expression of CCR gene in Leucaena increased up to 15 d in case of roots and stem as revealed by QRT-PcR studies in 0-15 d old seedlings. ELISA based studies of extractable CCR protein corroborated with QRT-PCR data. CCR protein was immuno-cytolocalized around xylem tissue. Lignin estimation and expression studies of 5,10 and 15 d old stem and root suggest that CCR expression correlates with quantity of lignin produced, which makes it a good target for antisense down regulation for producing designer species for paper industry. (C) 2010 Elsevier Masson SAS. All rights reserved.
Keywords: Cinnamoyl-CoA reductase; Developing seedling; Leucaena leucocephala; Lignin biosynthesis

Extending nhc-catalysis: reaction of aldehydes with unconventional reaction partners - Biju, Akkattu T.; Kuhl, Nadine; Glorius, Frank (Accounts of Chemical Research, 2011)
Transition metal catalysis is a powerful means of effecting organic reactions, but it has some inherent drawbacks, such as the cost of the catalyst and the toxicity of the metals. Organocatalysis represents an attractive alternative and, in some cases, offers transformations unparalleled in metal catalysis. Unique transformations are a particular hallmark of N-heterocyclic carbene (NHC) organocatalysis, a versatile method for which a number of modes of action are known. The NHC-catalyzed umpolung (that is, the inversion of polarity) of electrophilic aldehydes, through formation of the nucleophilic Breslow intermediate, is probably the most important mode of action. In this Account, we discuss the reaction of Breslow intermediates with unconventional reaction partners.

Extrudate swell of linear and branched polyethylenes: ALE simulations and comparison with experiments - Ganvir, Vivek; Gautham, Basavarsu P.; Pol, Harshawardhan; Bhamla, M. Saad; Sclesi, Lino; Thaokar, Rochish; Lele, Ashish K.; Mackley, Malcolm (Journal of Non-Newtonian Fluid Mechanics, 2011)
Extrudate swell is a common phenomenon observed in the polymer extrusion industry. Accurate prediction of the dimensions of an extrudate is important for appropriate design of dies for profile extrusion applications. Prediction of extrudate swell has been challenging due to (i) difficulties associated with accurate representation of the constitutive behavior of polymer melts, and (ii) difficulties associated with the simulation of free surfaces, which requires special techniques in the traditionally used Eulerian framework. In a previous work we had argued that an Arbitrary Lagrangian Eulerian (ALE) based finite element formulation may have advantages in simulating free surface deformations such as in extrudate swell. In the present work we reinforce this argument by comparing our ALE simulations with experimental data on the extrudate swell of commercial grades of linear polyethylene (LLDPE) and branched polyethylene (LOPE). Rheological behavior of the polymers was characterized in shear and uniaxial extensional deformations, and the data was modeled using either the Phan-Thien Tanner (PTT) model or the eXtended Pom-Pom (XPP) model. Additionally, flow birefringence and pressure drop measurements were done using a 10:1 contraction-expansion (CE) slit geometry in a MultiPass Rheometer. Simulated pressure drop and contours of the principal stress difference were compared with experimental data and were found to match well. This provided an independent test for the accuracy of the ALE code and the constitutive equations for simulating a processing-like flow. The polymers were extruded from long (L/D=30) and short (L/D=10) capillaries dies at 190 degrees C. ALE simulations were performed for the same extrusion conditions and the simulated extrudate swell showed good agreement with the experimental data. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.
Keywords: ALE-FEM; extrudate swell; Flow birefringence; MultiPass Rheometer; PSD; PTT; XPP

Fabrication, thermal and electrical properties of polyphenylene sulphide/copper composites - Goyal, R. K.; Kambale, K. R.; Nene, S. S.; Selukar, B. S.; Arbuj, Sudhir S.; Mulik, Uttam P. (Materials Chemistry and Physics, 2011)
The thermal and electrical properties of high performance poly(phenylene sulphide) (PPS) composites reinforced up to 31 vol% Cu particles were investigated to be used as materials for electronic applications. The thermal stability and char yield of the composites increased significantly. Both pre- and post- glass transition coefficient of thermal expansion (CTE) of composites decreased significantly. The microhardness was increased by more than 50% compared to pure PPS matrix. Microhardness and CTE of composites correlated well with the rule of mixtures. A percolation threshold about 6 vol% Cu was obtained. The electrical conductivity was increased by about eight orders of magnitude for 18 vol% composite. Dielectric constant and dissipation factor of composites at 1 MHz was increased by about 6-fold and 70-fold compared to matrix, respectively. They decreased gradually with increasing frequency up to 1 MHz and thereafter, there was insignificant change. The scanning electron microscope showed almost uniform distribution of Cu particles in the matrix. Owing to better dimensional stability and good electrical properties, these composites are very promising for electronic applications. (C) 2011 Elsevier B.V. All rights reserved.
Keywords: Dielectric property; Electrical conductivity; hardness; Thermal expansion

Facile synthesis of unusual glycosyl carbamates and amino acid glycosides from propargyl 1,2-orthoesters as glycosyl donors - Shaikh, Ashif Y.; Sureshkumar, Gopalsamy; Pati, Debasish; Sen Gupta, Sayam; Hotha, Srinivas (Organic & Biomolecular Chemistry, 2011)
Propargyl 1,2-O-orthoesters are exploited for the synthesis of 1,2-trans O-glycosides of protected amino acids. N-Fmoc- and N-Cbz protected serine/threonine - benzyl/methyl esters reacted well with glucosyl-, galactosyl-, mannosyl- and lactosyl- derived propargyl 1,2-orthoesters affording respective 1,2-trans glycosides in good yields under AuBr(3)/4 angstrom MS Powder/CH(2)Cl(2)/rt. t-Boc serine derivative gave serine 1,2-orthoester and glycosyl carbamate. Optimized conditions enabled preparation of new glycosyl carbamates from N-Boc protected amines in a single step using gold catalysts and propargyl 1,2-orthoesters in excellent yields.

Fe(III) complex of biuret-amide based macrocyclic ligand as peroxidase enzyme mimic - Panda, Chakadola; Ghosh, Munmun; Panda, Tamas; Banerjee, Rahul; Sen Gupta, Sayam (Chemical Communications, 2011)
An Fe(III) complex of a biuret-amide based macrocyclic ligand that exhibits both excellent reactivity for the activation of H(2)O(2) and high stability, especially at low pH and high ionic strength, is reported.

Folding and unfolding movements in a [2]pseudorotaxane - Suresh, Moorthy; Mandal, Amal Kumar; Kesharwani, Manoj K.; Adarsh, N. N.; Ganguly, Bishwajit; Kanaparthi, Ravi Kumar; Samanta, Anunay; Das, Amitava (Journal of Organic Chemistry, 2011)
A new dibenzo[24]crown-8 derivative (1) was synthesized and functionalized with aromatic moieties such as naphthalene and coumarin units. These two fluorophores are known to form an effective FRET (Forster resonance energy transfer) pair, and this formed the basis for the design of this host crown ether derivative. Results of the steady-state and time-resolved fluorescence studies confirmed the resonance energy transfer between the donor naphthalene moiety and acceptor coumarin fragment, while NMR spectra and computational studies support a folded conformation for the uncomplexed crown ether 1. This was found to form an inclusion complex, a [2]pseudorotaxane type with imidazolium ion derivatives as the guest molecules with varying alkyl chain lengths ([C4mim]+ or [C10mim]+). The host crown ether (1) tends to adopt an open conformation on formation of the interwoven inclusion complex (1·[C4mim]+ or 1·[C10mim]+). This change in conformation, from the folded to a open one, was predicted by computational as well as 1H NMR studies and was confirmed by single crystal X-ray structure for one (1·[C4mim]+) of the two inclusion complexes. The increase in the effective distance between the naphthalene and coumarin moieties in the open conformation of these inclusion complexes was also supported by the decrease in the effective FRET process that was operational between naphthalene and coumarin moieties in the free molecule (1). Importantly, this inclusion complex formation was found to be reversible, and in the presence of a stronger base/polar solvent, such as triethyl amine/DMSO, the deprotonation/effective solvation of the cationic imidizolium ions ([C4mim]+ or [C10mim]+) resulted in decomplexation or dethreading with restoration of the original emission spectra for 1, which signifies the subsequent increase in the FRET process. Thus we could demonstrate that a molecular folding-unfolding type of movement in the crown ether derivative could be induced by chemical input as an imidazolium ion.

Functionalization of SBA-15 mesoporous materials using ``thiol-ene click'' michael addition reaction - Kumari, Sushma; Malvi, Bharmana; Ganai, Anal Kumar; Pillai, Vijayamohanan K.; Sen Gupta, Sayam (Journal of Physical Chemistry C, 2011)
Methacrylate-labeled SBA-15 has been successfully synthesized from calcined SBA-15 and commercially available 3-trichlorosilyl propylmethacrylate. This material undergoes efficient thiol-ene ``click reaction'' with a variety of both thiol and disulfide-containing substrates in aqueous and organic media. The products were thoroughly characterized by a variety of analytical techniques including multinuclear (C-13, Si-29) solid-state NMR, TG-DTA, and nitrogen adsorption desorption studies. Disulfide-containing substrates in which the TCEP-mediated reduction of the disulfide bond and its subsequent addition to the methacrylate group anchored in SBA-15 in one-pot were used to synthesize a silica-protein hybrid material composed of biotin-labeled SBA-15 and streptavidin. Electrochemically active material was synthesized from the reaction of ferrocene-containing thiol and the methacrylate-labeled SBA-15. The ease of synthesis for the methacrylate-labeled SBA-15 material together with its ability to undergo efficient chemoselective thiol-ene reaction would make it a very attractive platform for the development of covalently anchored enzymes and sensors.

Genome sequence of idiomarina sp strain a28l, isolated from pangong lake, india - Gupta, Hemant Kumar; Singh, Ajit; Sharma, Rakesh (Journal of Bacteriology, 2011)
Idiomarina sp. strain A28L was isolated from the alkaline brackish water of a high-altitude lake, Pangong Lake. Here, we present the draft genome of Idiomarina sp. strain A28L, which contains 2,591,567 bp with a G + C content of 45.5 mol% and contains 2,299 protein-coding genes and 56 structural RNAs.

Genome sequence of rheinheimera sp strain A13L, isolated from pangong lake, india - Gupta, Hemant Kumar; Gupta, Rinkoo Devi; Singh, Ajit; Chauhan, Nar Singh; Sharma, Rakesh (Journal of Bacteriology, 2011)
Rheinheimera sp. strain A13L, which has antimicrobial activity, was isolated from alkaline brackish water of the high-altitude Pangong Lake of Ladakh, India. Here we report the draft genome sequence of Rhienheimera sp. strain A13L (4,523,491 bp with a G + C content of 46.23%). The genome is predicted to contain genes for marinocine and colicin V production, which may be responsible for the antimicrobial activity of the strain.

Gold catalyzed glycosidations for the synthesis of sugar acrylate/acrylamide hybrids and their utility - Thadke, Shivaji A.; Kar, Mritunjoy; Sen Gupta, Sayam; Hotha, Srinivas (Carbohydrate Research, 2011)
Propargyl glyco 1,2-orthoesters were exploited for the efficient synthesis of interesting glycomonomers such as glyco-acrylates and acrylamides using gold catalysts. It was observed that propargyl glyco 1,2-orthoesters with hydroxyethyl acrylates gives very good yield of the corresponding glyco-acrylates in a single step in the presence of catalytic amount of gold(III) catalyst; whereas, gold catalyzed glycosidation reaction on hydroxyethyl acrylamides was found to yield the corresponding acrylamidoyl 1,2-orthoester which was then converted to the corresponding glycol-acrylamide in the presence of catalytic amount of TMSOTf. Synthesized glyco-acrylate/acrylamide monomers are shown to undergo thiolate addition as well as free radical polymerization (C) 2011 Elsevier Ltd. All rights reserved.
Keywords: carbohydrates; Glycoacrylamides; Glycoacrylates; Glycopolymers; glycosylation; Gold

Growth and structural properties of Mg-N (N=10-56) clusters: density functional theory study - Heidari, Ideh; De, Sandip; Ghazi, S. M.; Goedecker, Stefan; Kanhere, Dilip G. (Journal of Physical Chemistry A, 2011)
Using the minima hopping global geometry optimization method on density functional potential energy surface, we have studied the structural and electronic properties of magnesium clusters for a size range of Mg-N where N = 10-56. Our exhaustive search reveals that most of our global minima are nonsymmetric in the size range above N = 20. We elucidate the evolutionary trend of the entire series and present more details about the peculiar growth of the clusters. For N> 20, it is possible to divide the cluster into two regions: the core region and the surface region. It turns out that the growth follows a peculiar cyclic pattern where the core and surface grow alternatively. The surface energy, as a function of number of atoms shows a clear signature as the number of atoms in the core increases by one. We have also carried out stability analysis and the stable sizes(magic numbers) agree very well with the experimental magic numbers reported by Diederich [J. Chem. Phys. 2011, 134, 124302]. We point out the similarities and differences between our results and sodium clusters.

Growth of aligned ZnO nanorods array on ITO for dye sensitized solar cell - Yengantiwar, Ashish; Sharma, Ramakant; Game, Onkar S.; Banpurkar, Arun G. (Current Applied Physics, 2011)
Aligned ZnO films of nanorods arrays were grown on Indium doped Tin oxide (ITO) glass substrate for the Dye Sensitized Solar Cells (DSSCs) applications. Two-step approach was employed for the deposition, which offers advantages such as excellent surface adhesion, large area deposition, high reproducibility and yield. Structural characterization using X-ray diffraction (XRD) shows a preferred c-axis (002) oriented growth. Scanning Electron Microscopy (SEM) images reveals uniformly distributed hexagonal ZnO nanorods with average diameter varying from 80 to 250 nm. Average growth rate of the films was estimated using Surface Profilometer which was found to be similar to 1 mu m/h. Optical characterizations were carried out using Photo-spectrometer and Raman spectroscopy. The DSSCs using these ZnO films of nanorods array as photo-electrodes show conversion efficiency ranging from 0.24 to -0.71 %, the maximum efficiency was obtained for films deposited for time duration 8 h. (C) 2010 Elsevier B.V. All rights reserved.
International Conference on Electronic Materials (IUMRS-ICEM), Seoul, SOUTH KOREA, AUG 22-27, 2010
Keywords: Aligned ZnO nanorod growth; Dye sensitized solar cell; Open aqueous solution deposition

Halogen bonding in 2,5-dichloro-1,4-benzoquinone: insights from experimental and theoretical charge density analysis - Hathwar, Venkatesha R.; Gonnade, Rajesh G.; Munshi, Parthapratim; Bhadbhade, Mohan M.; Row, Tayur N. Guru (Crystal Growth & Design, 2011)
Experimental charge density distribution in 2, 5-dichloro-1, 4-benzoquinone has been carried out using high resolution X-ray diffraction data at 90 K to quantitatively evaluate the nature of C-Cl center dot center dot center dot O=C halogen bond in molecular crystals. Additionally, the halogen bond is studied from geometrical point of view and the same has been visualized using Hirshfeld surface analysis. The obtained results from experimental charge density analysis are compared with periodic quantum calculations using B3LYP 6-31G(d,p) level of theory. The topological values at bond critical point, three-dimensional static deformation density features and electrostatic potential isosurfaces unequivocally establish the attractive nature of C-Cl center dot center dot center dot O=C halogen bond in crystalline lattice.

Hyper-production of beta-glucosidase and beta-xylosidase by aspergillus niger NCIM 1207 In Xylan-Containing Media - Khisti, Ujwala; Bastawade, Kulbhushan B.; Gokhale, Digambar V. (Bioresources, 2011)
Aspergillus niger NCIM 1207 produced significantly high levels of beta-glucosidase and beta-xylosidase activities in submerged fermentation. Cellulose induced only beta-glucosidase, while xylan induced both beta-glucosidase and beta-xylosidase activities. Both the enzymes of this strain were found to undergo catabolite repression in the presence of high concentrations of glucose and glycerol. The sudden drop in pH of the fermentation medium below 3.5 caused the inactivation of enzymes when the fungus was grown in glycerol-containing media at lower temperatures. The growth of the organism at 36 degrees C led to an increase in pH of the fermentation above 6.0 that affected beta-xylosidase activity significantly. Highest levels of beta-glucosidase ((19 IU mL(-1) or 633 IU g(-1) of substrate) and beta-xylosidase (18.7 IU/mL(-1) or 620 IU g(-1) of substrate) activities were detected when A. niger was grown at 30 degrees C for first five days followed by further incubation at 36 degrees C. Such a process of growing the organism at lower temperatures (growth phase) followed by producing the enzymes at higher temperatures (production phase) in case of fungal systems has not been reported so far. The zymogram staining of the beta-glucosidase demonstrated that A. niger produced only single species of beta-glucosidase. We feel that A. niger NCIM 1207 is a potential candidate to produce both beta-glucosidase and beta-xylosidase in high amounts that can be used to supplement commercial cellulase preparations.
Keywords: Aspergillus niger NCIM 1207; beta-glucosidase production; beta-xylosidase production

Identification of sublattice damages in swift heavy ion irradiated N-doped 6H-SiC polytype studied by solid state NMR - Viswanathan, E.; Kanjilal, D.; Sivaji, K.; Ganapathy, Subramanian (Journal of Physical Chemistry B, 2011)
We have studied N-doped 6H-SiC in its pristine and Swift Heavy Ion (SHI) irradiated (150 MeV Ag12+ ions) forms by solid state Nuclear Magnetic Resonance (NMR) at 7.01 T using C-13 and Si-29 as probe nuclei under magic angle spinning. We show that increased levels of nitrogen doping, than used before, lead to the observation of Knight shifts emanating from an increase in electron density in the conduction band, which in C-13 far exceed those in Si-29 MAS spectra. We have rationalized the differential effects in the MAS spectra and site-dependent paramagnetic shifts in terms of the nitrogen doping at the A, B, and C lattice sites. N-doping has a profound effect on Si-29 spin-lattice relaxation, and the site-dependent relaxation behavior is attributed to a difference in conduction electron properties at the different lattice sites. Si-29 T-1 measurements serve to identify the sublattice damages in SHI irradiated 6H-SiC. By determining the spin-lattice relaxation rates as a function of the SHI irradiation ion fluences, the change in relaxation behavior is correlated to the damage production mechanism. The sublattice damage leads to discernable changes in the interaction between the mobile unpaired electrons in the conduction band and the nuclear site, which profoundly influence the NMR relaxation properties. Our relaxation studies also provide evidence for site-dependent localized effects and a decrease in carrier spin density in the conduction band for the SHI irradiated 6H-SiC.

Incorporation of zirconium in medium-pore aluminophosphate molecular sieves with AFO framework - Chakrabortty, Dhruba; Ganguli, J. N.; Satyanarayana, C. V. V. (Microporous and Mesoporous Materials, 2011)
Zirconium substituted medium pore microporous aluminophosphate molecular sieve ZrAPO-41 was prepared by hydrothermal synthesis under autogenous pressure The formation of the pure phase was confirmed by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM)The thermal behaviour of the material was investigated by carrying out thermogravimetric/differential thermal analysis (TGA/DTA) The zirconium environment was studied by magic-angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy which suggests incorporation of zirconium into the framework UV-Visible diffuse reflectance study also supports the claim The temperature programmed desorption (TPD) of ammonia reveals that the acidity of ZrAPO 41 samples is higher than that of pure AlPO4-41 The catalytic activity of the samples was investigated through phenol hydroxylation reaction The result show hi E her catalytic activity for ZrAPO-41 samples compared to AlPO4-41 (C) 2010 Elsevier Inc All rights reserved
Keywords: AFO; Aluminophosphate; catalysis; Molecular sieve; ZrAPO 41

Increase in efficiency of media utilization for recombinant protein production in Chinese hamster ovary culture through dilution - Thombre, Shreya; Gadgil, Mugdha (Biotechnology and Applied Biochemistry, 2011)
Animal cells are extensively used for the large-scale production of recombinant proteins. Processes and genetically engineered cell lines have been developed to enhance longevity of the culture and increase protein productivity. In this study, we tested the effect of diluting a culture of Chinese hamster ovary (CHO) cells with phosphate-buffered saline (PBS) on cell growth and efficiency of media utilization. An immunoglobulin G-expressing CHO cell line was cultured in CD CHO media followed by dilution of the culture with PBS after the end of the exponential phase. A 28% and 61% increase in protein yield per milliliter of media was observed in the diluted culture in the batch and fed-batch mode with glucose and protein hydrolysate feeding, respectively. To aid in analyzing the potential causes of this observed increase, an unstructured mathematical model was constructed using previously reported kinetics to simulate cell growth, nutrient utilization, and protein production. The model predicts an increase in recombinant protein yield per milliliter of media in PBS diluted cultures under both batch and fed-batch conditions, and suggests that this observed increase could at least partly be due to a decrease in inhibitor concentration in the diluted culture.
Keywords: chemically defined media; culture dilution; glucose consumption; inhibitor formation; recombinant protein yield

Influence of reactive compatibilization on the structure and properties of PP/LDH nanocomposites - Lonkar, Sunil P.; Therias, Sandrine; Leroux, Fabrice; Gardette, Jean Luc; Singh, Raj Pal (Polymer International, 2011)
Polypropylene (PP)/layered double hydroxide (LDH) nanocomposites were prepared by the direct melt intercalation method usingmaleic anhydride grafted polypropylene (PP-g-MAH) as a reactive compatibilizer. The compatibilization effects provided by PP-g-MAH in different weight fractions and their influence on the structure and properties of the final nanocomposites were investigated. The interactions and structural morphology of the nanocomposites were examined by Fourier transform infrared spectroscopy, X-ray diffraction and transmission electronmicroscopy. Thermal, mechanical and rheological properties of these nanocomposites were investigated as a function of compatibilizer concentration. The detailed morphological and X-ray diffraction results revealed that the degree of LDH dispersion increases as the amount of PP-g-MAH increases. Study of the linear viscoelastic properties showed that the storage modulus G' is very sensitive to the microstructure of the nanocomposite. The thermal properties of the nanocomposites were significantly influenced by the weight fraction of PP-g-MAH due to the shielding and nucleating effect of exfoliated layers. Both the tensile strength and modulus showed substantial improvements with increasing PP-g-MAH content, while the elongation at break substantially decreased, although the presence of PP-gMAH somewhat improves these values. The overall results showed that 10 wt% of compatibilizer is optimum to achieve nanocomposites with better performance. (C) 2011 Society of Chemical Industry
Keywords: compatibilization; layered double hydroxides; Nanocomposites; polypropylene; Rheology; thermomechanical properties

Interfacial electron transfer dynamics of two newly synthesized catecholate bound ruII polypyridyl-based sensitizers on TiO2 nanoparticle surface - a femtosecond pump probe spectroscopic study - Banerjee, Tanmay; Rawalekar, Sachin; Das, Amitava; Ghosh, Hirendra Nath (Europian Journal of Inorganic Chemistry, 2011)
Two new catecholate-bound RuII–polypyridine based sensitizers, (2,2′-bipyridine){ethyl 3-(4-hydroxyphenyl)-2-[(4′-methyl-2,2′-bipyridinyl-4-carbonyl)amino]propionate}{4-[2-(4′-methyl-2,2′-bipyridinyl-4-yl)vinyl]benzene-1,2-diol)}ruthenium(II) hexafluorophosphate (5) and [(2,2′-bipyridine)-(4-2,2′-bipyridinyl-4-yl-phenol)-(4-{2-(4′-methyl-2,2′-bipyridinyl-4-yl)vinyl}benzene-1,2-diol)]ruthenium(II) hexafluorophosphate (6) with secondary electron-donating groups (tyrosine and phenol, respectively) were synthesized and characterized. Steady-state optical absorption and emission studies confirm strong coupling between the sensitizers and TiO2 nanoparticles. Femtosecond visible transient absorption spectroscopy has been employed to study interfacial electron transfer (IET) dynamics in the dye–nanoparticle systems to explore the influence of the secondary electron-donating groups on IET dynamics. Electron injection into the conduction band of nanoparticulate TiO2 has been confirmed by detection of the conduction band electrons in TiO2 ([e–]TiO2CB) and radical cation of the adsorbed dye (D·+) in real time monitored by transient absorption spectroscopy. A single exponential and pulse-width limited (< 100 fs) electron injection has been observed. Back electron transfer (BET) dynamics have been studied by monitoring the decay kinetics of the injected electron in the conduction band of TiO2 and by the recovery of the ground state bleach. BET dynamics in dye–TiO2 systems for complexes 5 and 6 have been compared with those of [bis(2,2′-bpy)-(4-{2-(4′-methyl-2,2′-bipyridinyl-4-yl)vinyl}benzene-1,2-diol)]ruthenium(II) hexafluorophosphate (7), which does not have a secondary electron-donating group.

Jack bean alpha-mannosidase (Jb alpha-man): tolerance to alkali, chelating and reducing agents and energetics of catalysis and inhibition - Kumar, Avinash; Gaikwad, Sushama M. (International Journal of Biological Macromolecules, 2011)
Investigations of the catalytic and structural transitions of jack bean alpha-mannosidase (Jb alpha-man) are described in the present paper. The enzyme was maximally stable at pH 5.0; however, when incubated in the pH range of 11.0-12.0, showed 1.3 times higher activity and also stability for longer time. The free amino group at or near the active site was probably involved in the stability and activation mechanism. The active site is constituted by the association of two unidentical subunits connected by disulfide linkages. The metalloenzyme has Zn(2+) ions tightly bound and chelation reduces the thermal stability of the protein. Energetics of catalysis and thermodynamics of inhibition of the enzyme were also carried out. (C) 2011 Elsevier B.V. All rights reserved.
Keywords: Alkali tolerance; alpha-Mannosidase; beta-Mercaptoethanol; Energetics; Inhibition; Metalloenzyme

Kinetics of nitric oxide adsorption on Pd(111) surfaces through molecular beam experiments: a quantitative study - Nagarajan, Sankaranarayanan; Thirunavukkarasu, Kandasamy; Gopinath, Chinnakonda S.; Prasad, Sudarsan D. (Journal of Physical Chemistry C, 2011)
A detailed kinetic picture derived by molecular beam studies of the adsorption-desorption of the NO/Pd(111) system is presented. Numerical simulations and detailed kinetic analysis show that the precursor state model of adsorption provides a valid picture of the sticking coefficient variation with surface coverage, especially at low temperatures. At higher temperatures, the precursor model gives way to the Langmuir molecular model of adsorption. All the parameters of the precursor state model have been quantified. Temperature programmed desorption (TPD) studies further show that there is a slight repulsive interaction between adsorbed NO molecules and there is only a negligible fraction of dissociated molecules on the surface for temperatures less than 500 K, as the Pd(111) surface is defect free. A Bragg-Williams (BW) lattice gas model with repulsive interactions, within the framework of mean field approach (MFA), is shown to describe the TPD spectra reasonably well.

Ligand dynamics controlled reverse spin cross over in bis pyrazolyl pyridine based Fe(II) complex cation with metallodithiolato anions with an example of a ferromagnetic 2:1 cocrystal of mixed Ni(III)/Ni(II) oxidation states - Manoharan, Periakaruppan T.; Sambandam, Balaji; Amsarani, Ramamoorthy; Varghese, Babu; Gopinath, Chinnakonda S.; Nomura, Kiyoshi (Inorganica Chimica Acta, 2011)
We report here the crystal and molecular structures of three compounds [FeL(2)] [Ni(mnt)(2)] (1), [FeL(2)](2) [Ni(mnt)(2)](3)center dot 2H(2)O (2) and [FeL(2)] [Cu(mnt)(2)]center dot 2CH(3)CN (3) where L = 2,6-bis(3,5-dimethylpyrazol-1-ylmethyl) pyridine and mnt = maleonitriledithiolate, and their detailed spectroscopic and magnetic properties using variable temperature Mssbauer, EPR, susceptibility studies, along with room temperature electron spectroscopy for chemical analysis (ESCA) studies. The observed temperature dependant high spin/low spin (HS/LS) ratios of [FeL(2)](2+) cations in these lattices, exhibiting `reverse spin cross-over' measured unequivocally by Mssbauer, have been interpreted as resulting from differing amount of `void space' in the lattice, a measure of the ease of lattice dynamics originating from ligand L. Differential scanning calorimetric data points this HS/LS transition to order-disorder type of second order phase transitions. While trying to test this lattice dynamics controlled property of [FeL(2)](2+) cations an unusual behavior of cocrystallization of two planar complex anions of the same type in two different oxidation states, viz. [Ni(mnt)(2)](2) and [Ni(mnt)(2)] , was observed in [FeL(2)](2+) [Ni(mnt(2))](3), supported by crystallography, ESCA chemical shifts of Ni 2p(3/2) and EPR. The susceptibility data in combination with ESCA chemical shifts of S 2p(3/2) and Ni 2p(3/2) on all the compounds reveal the importance of charge transfer between the two counter ions. (C) 2011 Elsevier B.V. All rights reserved.
Keywords: Iron complexes; Magnetism; Reverse-spin crossover; X-ray crystal structures

Liquid phase oxidation of p-vanillyl alcohol over synthetic Co-saponite catalyst - Garade, Ajit C.; Biradar, Narayan S.; Joshi, S. M.; Kshirsagar, V. S.; Jha, Ratnesh Kumar; Rode, Chandrashekhar V. (Applied Clay Science, 2011)
Effect of cobalt loading on porosity of synthetic Co-saponite catalysts and on the air oxidation of p-vanillyl alcohol was studied by varying Co content in the range of 5% to 30% using in situ precipitation method. The pore size increased from 1.29 to 3.69 nm indicating a transition from micro to meso porosity, with increase in Co loading from 5% to 30%. The distribution ratio of Co(3)O(4)/CoO phases as estimated from TPR studies, also increased from 0.84 to 1.67 with increase in Co loading from 5% to 13% and remained almost constant (1.7) with further increase in Co loading up to 30%. The highest activity (conversion 55%) and selectivity of 99% to p-vanillin obtained for 13% Co-saponite in p-vanillyl alcohol oxidation was due to the highest distribution ratios of Co(3)O(4)/CoO phases. (C) 2010 Elsevier B.V. All rights reserved.
Keywords: Co-saponite; Cobalt oxide phase ratio; p-Vanillin; p-Vanillyl alcohol oxidation; Porosity transition; Temperature programmed reduction

Magnetite/CdTe magnetic-fluorescent composite nanosystem for magnetic separation and bio-imaging - Kale, Anup; Kale, Sonia; Yadav, Prasad; Gholap, Haribhau; Pasricha, Renu; Jog, Jyoti Prakash; Lefez, Benoit; Hannoyer, Beatrice; Shastry, Padma; Ogale, Satishchandra B. (Nanotechnology, 2011)
A new synthesis protocol is described to obtain a CdTe decorated magnetite bifunctional nanosystem via dodecylamine (DDA) as cross linker. High resolution transmission electron microscopy (HRTEM), energy-dispersive x-ray spectroscopy (EDAX), vibrating sample magnetometry (VSM), Fourier transform infrared spectroscopy (FTIR), diffuse reflectance spectroscopy (DRS) and fluorescence microscopy are used to characterize the constitution, size, composition and physical properties of these superparamagnetic-fluorescent nanoparticles. These CdTe decorated magnetite nanoparticles were then functionalized with anti-epidermal growth factor receptor (EGFR) antibody to specifically target cells expressing this receptor. The EGFR is a transmembrane glycoprotein and is expressed on tumor cells from different tissue origins including human leukemic cell line Molt-4 cells. The magnetite-CdTe composite nanosystem is shown to perform excellently for specific selection, magnetic separation and fluorescent detection of EGFR positive Molt-4 cells from a mixed population. Flow cytometry and confocal laser scanning microscopy results show that this composite nanosystem has great potential in antibody functionalized magnetic separation and imaging of cells using cell surface receptor antibody.

Mapping of QTLs governing agronomic and yield traits in chickpea - Gowda, S. J. M.; Radhika, P.; Mhase, L. B.; Jamadagni, B. M.; Gupta, V. S.; Kadoo, Narendra Y. (Journal of Applied Genetics, 2011)
Chickpea is one of the most important leguminous cool season food crops, cultivated prevalently in South Asia and Middle East. The main objective of this study was to identify quantitative trait loci (QTLs) associated with seven agronomic and yield traits in two recombinant inbred line populations of chickpea derived from the crosses JG62xVijay (JV population) and VijayxICC4958 (VI population) from at least three environments. Single locus QTL analysis involved composite interval mapping (CIM) for individual traits and multiple-trait composite interval mapping (MCIM) for correlated traits to detect pleiotropic QTLs. Two-locus analysis was conducted to identify the main effect QTLs (M-QTLs), epistatic QTLs (E-QTLs) and QTL x environment interactions. Through CIM analysis, a total of 106 significant QTLs (41 in JV and 65 in VI populations) were identified for the seven traits, of which one QTL each for plant height and days to maturity was common in both the populations. Six pleiotropic QTLs that were consistent over the environments were also identified. LG2 in JV and LG1a in VI contained at least one QTL for each trait. Hence, concentrating on these LGs in molecular breeding programs is most likely to bring simultaneous improvement in these traits.
Keywords: Cicer arietinum; QTL analysis; QTL x environment interaction; Two-locus analysis; Yield traits

MgCl2 center dot 6PhCH(2)OH - a new molecular adduct as support material for ziegler-natta catalyst: synthesis, characterization and catalytic activity - Gnanakumar, Edwin S.; Thushara, K. S.; Bhange, Deu S.; Mathew, Renny; Ajithkumar, Thalasseril G.; Rajamohanan, P. R.; Bhaduri, Sumit; Gopinath, Chinnakonda S. (Dalton Transactions, 2011)
Benzyl alcohol has been used to prepare a single phase MgCl2 center dot 6BzOH molecular adduct as a support for an ethylene polymerization catalyst (Ziegler catalyst). The structural, spectroscopic and morphological aspects of the MgCl2 center dot 6BzOH molecular adduct and the Ziegler catalyst have been thoroughly studied by various physicochemical characterization techniques. The presence of MgO6 octahedrons due to the interaction of Mg2+ with six -OH groups of the benzyl alcohol is confirmed from a Raman feature at 703 cm(-1), and structural studies. The supported catalyst activity has been evaluated for the ethylene polymerization reaction. The lower polymerization activity of the titanated Ziegler-Natta catalyst compared with a standard catalyst is attributed to the strong interaction of titanium chloride with the support and associated electronic factors.

Morphological changes in nanoparticulate silver films due to electron beam irradiation of polystyrene substrates - Pattabi, Manjunatha; Gurumurthy, S. C.; Sanjeev, Ganesh; Gaikwad, A. B. (Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions With Materials and Atoms, 2011)
Results of the studies on the effect of 8 MeV electron beam irradiation of polystyrene substrates on the morphology of silver particulate films deposited at 455 K in a vacuum of 8 x 10(-6) Torr are reported. Optical absorption studies show the presence of transverse and longitudinal plasmon resonance for films deposited on irradiated polystyrene. Scanning electron microscopy reveals a decrease in particle size with smaller inter-particle separation for irradiated films. Larger clusters are formed in the case of films deposited on polystyrene after 300 h of irradiation. In this paper, we show that the morphology of silver nanoparticulate films can be modified by electron irradiation of inert polymer substrates like polystyrene. The change observed due to irradiation is attributed to the formation of free radicals, thereby altering the polymer-metal interaction. (C) 2011 Elsevier B.V. All rights reserved.
Keywords: Electron bombardment; Optical properties; Particulate films; Polymers; Silver; surface morphology

N-Heterocyclic carbene catalyzed umpolung of michael acceptors for intermolecular reactions - Biju, Akkattu T.; Padmanaban, Mohan; Wurz, Nathalie E.; Glorius, Frank (Angewandte Chemie-International Edition, 2011)
eahciM! The N-heterocyclic carbene catalyzed umpolung of Michael acceptors proceeds through the formation of a deoxy-Breslow intermediate (see scheme; EWG=electron-withdrawing group). This nucleophilic species can react with other Michael acceptors in an intermolecular fashion, thereby resulting in the formation of homo- or heterodimeric olefins. This “Michael umpolung” should become a valuable method for the formation of densely functionalized olefins.
Keywords: carbenes; Michael acceptors; nitrogen heterocycles; organocatalysis; umpolung

N-heterocyclic carbene-catalyzed cross-coupling of aromatic aldehydes with activated alkyl halides - Padmanaban, Mohan; Biju, Akkattu T.; Glorius, Frank (Organic Letters, 2011)
N-Heterocyclic carbene-catalyzed umpolung of aldehydes followed by their interception with diarylbromomethanes has been reported. This conceptually novel transition-metal-free cross-coupling of aldehydes with alkyl halides works well at low catalyst loadings and under mild reaction conditions leading to the formation of diaryl acetophenone derivatives in good yields. In addition, α-halo ketones and esters can also be used as aldehyde reaction partners.

Numerical and experimental studies on extrudate swell of branched polyethylene through axisymmetric and planar dies - Ganvir, Vivek; Gautham, Basavarsu P.; Thaokar, Rochish; Lele, Ashish K.; Pol, Harshwardhan (Journal of Polymer Engineering, 2011)
Extrudate swell is simulated using an Arbitrary Lagrangian Eulerian (ALE) technique based finite element formulation and the same has been validated by comparing the results with reported numerical and experimental studies. In the present work we compare our ALE simulations with our own experimental data on the extrudate swell of commercial grade low density polyethylene (LDPE) resin. The resins were characterized for their rheological behavior in both shear and uniaxial extension. The polymers were extruded from a capillary under isothermal conditions and the extrudates were observed on-line using a video camera. ALE simulations were performed using molecular constitutive model like eXtended Pom-Pom (XPP) for branched (LDPE). The simulated extrudate swell was a good match with the experimental data. It was found that the swell values of LPDE through planar die are higher than the axisymmetric die.
Keywords: ALE-FEM; extrudate swell; polymer flow simulations; XPP

One-step in situ synthesis of NHx-adsorbed rhodium nanocrystals at liquid-liquid interfaces for possible electrocatalytic applications - Patil, V. S.; Krishna, S. R.; Hawaldar, Ranjit R.; Gaikwad, A. B.; Sathaye, S. D.; Patil, K. R. (Journal of Colloid and Interface Science, 2011)
Nearly monodisperse rhodium nanoparticles with adsorbed NHx were synthesized at the CCl4-water interface. The presence of NHx-adsorbed species was confirmed by energy-dispersive X-ray analysis (EDX) and X-ray photoelectron spectroscopy (XPS) studies. The synthesis of controlled size 2-38 nm rhodium particles was studied as a function of reducing agent concentration by transmission electron microscopy (TEM). HRTEM confirmed the formation of rhodium nanoparticles having fringe spacing consistent with reported Rh (1 1 1) planes. The continuity of these films over an area of 1 x 1 pm was revealed by atomic force microscopy (AFM) studies. The electrocatalytic application of these nanostructure Rh-NHx), thin films for formaldehyde oxidation in 0.5 M NaOH was investigated by cyclic voltammetry. The Rh nanoparticles formed by the present strategy are expected to be useful for other catalytic applications also. (C) 2011 Elsevier Inc. All rights reserved.
Keywords: Hydrazine hydrate; Liquid-liquid interface; Nanoparticles; Rhodium; Thin films

Oxidative carbonylation of amine using water-soluble palladium catalysts in biphasic media - Didgikar, Mahesh R.; Joshi, Sunil S.; Gupte, Sunil P.; Diwakar, Makarand M.; Deshpande, Raj Madhukar; Chaudhari, Raghunath V. (Journal of Molecular Catalysis A-Chemical, 2011)
Application of water-soluble palladium catalysts for oxidative carbonylation of aniline to N,N' diphenyl urea (DPU) has been reported. The water-soluble palladium catalysts prepared from sulfonated N-containing ligands were found to be highly stable under reaction conditions and easily recyclable due to insoluble urea product in the reaction medium. This is in contrast to the sulfonated phosphine ligands, which are vulnerable to oxidation under reaction conditions, showing poor activity and stability. Commercially available as well as laboratory synthesized ligands were used for preparing water-soluble palladium catalysts, for oxidative carbonylation of aniline. The best activity was obtained for Pd complex with disodium 2,2'-bipyridine-4,4'-disulfonate (Bipy-DS) ligand. Under optimized conditions Pd(BipyDS)Pd(OAc)(2) catalyst gave TOF of similar to 210h(-1) with aniline conversion of similar to 97% with similar to 91% selectivity for N.N'-diphenyl urea. It was found that the catalyst was easily reusable up to five times, with negligible loss in the catalytic activity. The effect of reaction parameters was investigated and a plausible reaction mechanism has been proposed. (C) 2010 Elsevier B.V. All rights reserved.
Keywords: Amine; Biphasic catalysis; Carbonylation; Urea; Water-soluble palladium catalyst

Oxidative dehydrogenation of ethylbenzene using nitrous oxide over vanadia-magnesia catalysts - Shiju, N. Raveendran; Anilkumar, Mettu; Gokhale, S. P.; Rao, B. Seshagiri; Satyanarayana, C. V. V. (Catalysis Science & Technology, 2011)
A series of V-Mg-O catalysts with different loadings of vanadia were prepared by the wet impregnation method and the effect of the local structure of these catalysts on the oxidative dehydrogenation of ethylbenzene with N(2)O was investigated. High styrene selectivity (similar to 97%) was obtained at 773 K. The characterization of catalysts with methods such as XRD, FTIR, UV-visible, TPR, NMR and Laser Raman spectroscopy suggested that magnesium orthovanadate is the predominant vanadium containing phase and the size of the orthovanadate domains increases with increasing vanadia loading. The rate of ODH of ethylbenzene per V atom increases with vanadia loading and reaches a maximum at 10 wt%. The specific activity, i.e. the conversion of ethylbenzene per unit surface area of the catalysts, also exhibited a maximum at a vanadia loading of 10 wt% leading to the conclusion that activity of these catalysts is due to the presence of very small domains of Mg(3)(VO(4))(2) on the surface of MgO rather than crystallites of bulk Mg(3)(VO(4))(2). The higher styrene yield in the presence of N(2)O can be ascribed to the ability of N(2)O to keep vanadium species at a higher oxidation state.

Perspectives for nano-biotechnology enabled protection and nutrition of plants - Ghormade, Vandana; Deshpande, Mukund V.; Paknikar, Kishore M. (Biotechnology Advances, 2011)
Indiscriminate use of pesticides and fertilizers causes environmental pollution, emergence of agricultural pests and pathogens, and loss of biodiversity. Nanotechnology, by virtue of nanomaterial related properties, has potential agro-biotechnological applications for alleviation of these problems. The literature pertaining to the role of nanotechnology in plant and soil systems demonstrates that nanomaterials may assist in a) the controlled release of agrochemicals for nutrition and protection against pests and pathogens, b) delivery of genetic material, c) sensitive detection of plant disease and pollutants and d) protection and formation of soil structure. For instance, porous silica (15 nm) and biodegradable, polymeric chitosan (78 nm) nanoparticles displayed slow release of encapsulated pesticide and fertilizer, respectively. Further, nanosized gold (5-25 nm) delivered DNA to plant cells while iron oxide (30 nm) based nanosensors detected pesticides at minute levels. These functions assist the development of precision farming by minimizing pollution and maximizing the value of farming practice. (C) 2011 Elsevier Inc. All rights reserved.
Keywords: Biofertilizer; Biopesticides; Controlled delivery; Fertilizer; Genetic material; Nanomaterials; Nanosensors; Pathogen; Pesticides; Residues

Photoactive RuII-polypyridyl complexes that display sequence selectivity and high-affinity binding to duplex DNA through groove binding - Ghosh, Amrita; Das, Priyadip; Gill, Martin R.; Kar, Prasenjit; Walkar, Michael G.; Thomas, Jim A.; Das, Amitava (Chemistry A European Journal, 2011)
The duplex-DNA binding properties of a nonintercalating polypyridyl ruthenium(II) complex that incorporates a linear extended ligand with a catechol moiety has been probed with a variety of photo- and biophysical techniques. These studies reveal that the complex groove binds to DNA sequences biphasically, and displays binding constants equivalent to those of high-affinity metallointercalators. The complex also displays preferential binding to AT-rich sequences. Changes in the structure of the coordinated catechol ligand and the incorporation of intercalating ancillary ligands into the complex were found to modulate both the optical-binding response and binding parameters of the system, which indicates that the catechol moiety plays a crucial role in the observed enhancement to binding affinities.

Photoelectrochemical applications of In2Se3 thin films by chemical deposition - Hankare, P. P.; Rathod, K. C.; Asabe, M. R.; Jadhav, A. V.; Helavi, V. B.; Chavan, Santosh S.; Garadkar, K. M.; Mulla, Imtiaz S. (Journal of Materials Science-Materials in Electronics, 2011)
Indium selenide films have been synthesized by chemical bath deposition method onto stainless steel plate. The configuration of fabricated cell is n-In2Se3| NaOH(1 M) + S(1 M) + Na2S(1 M) |C-(graphite). Characterization of the photoelectrochemical cell was carried out by studying X-ray diffraction, current-voltage and capacitance-voltage characteristics in the dark, barrier height measurements, power output, photoresponse and spectral response. The study shows that the In2Se3 thin films are n-type semiconductor. The junction ideality factor was found to be 3.24. The flat band potential and the barrier height were found to be 0.720 V and 0.196 eV, respectively. From the study of power output characteristics, open circuit voltage, short circuit current, fill factor and efficiency were found to be 310 mV, 20 mu A, 37.64 and 0.61%, respectively. Photoresponse studies show that the lighted ideality factor is 2.78. Maximum current was observed at 575 nm.

Photophysical properties of ligand localized excited state in ruthenium(ii) polypyridyl complexes: a combined effect of electron donor-acceptor ligand - Verma, Sandeep; Kar, Prasenjit; Das, Amitava; Ghosh, Hirendra Nath (Dalton Trans, 2011)
We have synthesized ruthenium(II) polypyridyl complexes (1) Ru(II)(bpy)2(L1), (2) Ru(II)(bpy)2(L2) and (3) Ru(II)(bpy)(L1)(L2), where bpy = 2,2′-bipyridyl, L1 = 4-[2-(4′-methyl-2,2′-bipyridinyl-4-yl)vinyl]benzene-1,2-diol) and L2 = 4-(N,N-dimethylamino-phenyl)-(2,2′-bipyridine) and investigated the intra-ligand charge transfer (ILCT) and ligand–ligand charge transfer (LLCT) states by optical absorption and emission studies. Our studies show that the presence of electron donating –NMe2 functionality in L2 and electron withdrawing catechol fragment in L1 ligands of complex 3 introduces low energy LLCT excited states to aboriginal MLCT states. The superimposed LLCT and MLCT state produces redshift and broadening in the optical absorption spectra of complex 3 in comparison to complexes 1 and 2. The emission quantum yield of complex 3 is observed to be extremely low in comparison to that of complex 1 and 2 at room temperature. This is attributed to quenching of the 3MLCT state by the low-emissive 3LLCT state. The emission due to ligand localized CT state (ILCT and LLCT) of complexes 2 and 3 is revealed at 77 K in the form of a new luminescence band which appeared in the 670–760 nm region. The LLCT excited state of complex 3 is populated either via direct photoexcitation in the LLCT absorption band (350–700 nm) or through internal conversion from the photoexcited 3MLCT (400–600 nm) states. The internal conversion rate is determined by quenching of the 3MLCT state in a time resolved emission study. The internal conversion to LLCT and ILCT excited states are observed to be as fast as ∼200 ps and ∼700 ps for complexes 3 and 2, respectively. The present study illustrates the photophysical property of the ligand localized excited state of newly synthesized heteroleptic ruthenium(II) polypyridyl complexes.

PNAs grafted with (alpha/gamma, R/S)-aminomethylene pendants: Regio and stereo specific effects on DNA binding and improved cell uptake - Mitra, Roopa; Ganesh, Krishna N. (Chemical Communications, 2011)
PNAs grafted with cationic aminomethylene (am) pendants on the backbone at the glycyl (alpha) or ethylenediamine (gamma) segments show regio (alpha/gamma) and stereochemistry (R/S) dependent binding with complementary DNA. These are efficiently taken up by cells, with gamma(S-am) aeg-PNA being the best in all properties.

Porosity driven photocatalytic activity of wormhole mesoporous TiO2-xNx in direct sunlight - Sivaranjani, Kumarsrinivasan; Gopinath, Chinnakonda S. (Journal of Materials Chemistry, 2011)
Results obtained by combining four important factors simultaneously, namely, wormhole mesoporosity with low diffusion length for charge carriers, high surface area, nanoparticles with high crystallinity, and visible light absorption due to N-doping, in titania (meso-TiO2-xNx) are reported. Meso-TiO2-xNx materials have been prepared by a combustion method within 10 min and by varying urea : Ti(NO3)(4) between 1 (UT1) and 10 (UT10). All of the prepared materials have been thoroughly characterised. Nanocrystalline anatase phase with high surface area (234 m(2) g(-1)), and type-IV H-3-mesoporosity is observed with UT10. Photocatalytic rhodamine-B degradation was employed to screen for the activity of the materials, and p-anisyl alcohol oxidation to p-anisaldehyde was carried out successfully in aqueous solution under direct sunlight. High photocatalytic activity of UT10 in direct sunlight, in spite of high band gap (3.24 eV), is attributed to the better utilization of holes due to the low charge diffusion barrier associated with wormhole mesoporosity along with highly crystalline, however, nanoparticulate TiO2-xNx.

Possible deNO(x) management under net oxidizing conditions: a molecular beam study of (NO)-N-15+CO+O-2 reaction on Pd(111) surfaces - Nagarajan, Sankaranarayanan; Thirunavukkarasu, Kandasamy; Gopinath, Chinnakonda S. (Journal of Physical Chemistry C, 2011)
Isothermal kinetic measurements of (NO)-N-15 reduction with CO on Pd(111) surfaces were carried out under net-oxidizing conditions with (NO)-N-15 + CO + O-2, using a molecular beam instrument (MBI). Transient state (TS) and steady state (SS) kinetic details of the above reaction were obtained for a wide range of temperature and beam compositions, especially with O-2-rich compositions. Increasing O-2 content, generally, suppresses (NO)-N-15 reduction in the SS; nonetheless, irrespective of O-2 content, N-15(2) was produced in TS, and to a significant extent under SS conditions too. Sustainable N-2 production between 450 and 600 K and with low to moderate amount of oxygen was observed, and the extent of NO decomposition was also quantified. The ratio of N-15(2): (N2O)-N-15 was generally found to be around 8:1 under most of the reaction conditions. Maxima in the SS reaction rates of all products were observed between 500 and 600 K. Compared to other elementary reaction steps, a slow decay observed with N + N -> N-2 step under SS beam oscillation conditions demonstrates its contribution to the rate limiting nature of the overall reaction. Fast beam switching experiments have been performed alternately between O-2-lean and -rich conditions, thus highlighting the effectiveness of (NO)-N-15 reduction in TS, irrespective of the beam composition. Possibly in a future technology initiative, this aspect could be exploited to manage more (NO)-N-15 reduction on Pd-based catalysts.

Probing the furanose conformation in the 2 `-5 ` strand of isoDNA:RNA duplexes by freezing the nucleoside conformations - Erande, Namrata D.; Gunjal, Anita D.; Fernandes, Moneesha; Kumar, Vaijayanti A. (Chemical Communications, 2011)
Sugar conformations in the isoDNA strand of isoDNA : RNA duplexes are preferred S-type locked/frozen in contrast to N-type locked conformations preferred in DNA: RNA duplexes.

Propargyl/methyl furanosides as potential glycosyl donors - Vidadala, Srinivasa Rao; Gayatri, Gaddamannugu; Sastry, G. Narahari; Hotha, Srinivas (Chemical Communications, 2011)
Transfuranosylations are not well studied though many similar studies exist for transpyranosylation; herein, we report that propargyl/methyl D-ribf- and D-lyxf- give only 1,2-trans glycosides whereas D-araf- and D-xylf- result in a mixture of 1,2-trans and 1,2-cis glycosides; observed facts are rationalised by computational studies.

Purification and characterization of bacterial aryl alcohol oxidase from sphingobacterium sp ATM and Its uses in textile dye decolorization - Tamboli, Dhawal P.; Telke, Amar A.; Dawkar, Vishal V.; Jadhav, Shekhar B.; Govindwar, Sanjay P. (Biotechnology and Bioprocess Engineering, 2011)
Aryl alcohol oxidase (AAO) produced by dye decolorizing bacteria Sphingobacterium sp. ATM, was purified 22.63 fold to a specific activity of 21.75 mu mol/min/mg protein using anion exchange and size exclusion chromatography. The molecular weight of the purified AAO was found to be 71 kDa using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and confirmed by zymography of AAO using L-dopa. The enzyme showed substrate specificity towards veratryl alcohol, followed by n-propanol. The optimum pH and temperature of purified AAO were found to be 3.0 and 40 degrees C, respectively. The K(m) and V(max) of AAO was 1.1615 mM and 3.13 mM/min when veratryl alcohol was used as substrate. Sodium azide showed maximum inhibition while ethylenediamine tetra acetic acid (EDTA), L-cysteine and dithiothreitol showed slight inhibition. Metal ions also showed slight inhibition. HPLC analysis confirmed the degradation of Direct Red 5B. The metabolite obtained after decolorization of Direct Red 5B was characterized as 3 diazenyl 7 [-(phenyl carbonyl) amino] naphthalene-2-sulfonic acid using GC-MS analysis.
Keywords: aryl alcohol oxidase; Direct Red 5B; dye decolorization; ion exchange chromatography; Sphingobacterium sp ATM

Receptor design and extraction of inorganic fluoride ion from aqueous medium - Das, Priyadip; Mandal, Amal Kumar; Kesharwani, Manoj K.; Suresh, Eringathodi; Ganguly, Bishwajit; Das, Amitava (Chemical Communications, 2011)
A receptor with acidic methylene hydrogens is found to act as an efficient binding mode for F−. This reagent could as well be used for selective and quantitative extraction of F− from the aqueous solution of NaF and sea water.

Removal of metal ions from aqueous solution using trioctyl phosphine oxide-containing mixed solvents in conjunction with a fibre-supported solid membrane - Gaikwad, Abaji G. (Adsorption Science & Technology, 2011)
A novel method has been developed for the removal of mercury, arsenic and tin ions using a fibre-supported solid membrane placed between the source phase and the receiving phase which contained trioctyl phosphine oxide (TOPO) in a mixed solvent. The fibre-supported solid membrane was prepared by the esterification of cellulose fibre with tartaric acid at 120 degrees C. The experimental variables explored were the initial concentration of the metal ion (10(-2) to 10(-4) M) in the source phase, the type of mixed solvent employed [containing TOPO, TOPO + acetone, TOPO + tetrahydrofuran, TOPO + 1,4-dioxane, TOPO + methanol, TOPO + ethanol or TOPO + 2-propanol (20-80% v/v)], the concentration of HCl (0.25-1 M) in the receiving phase and the stirring speed (50-130 rpm) of the bulk source and the receiving phase. The efficiency of the organic solvent in the mixed solvent followed the order: TOPO + tetrahydrofuran > TOPO + 1,4-dioxane > TOPO + acetone > TOPO + 2-propanol > TOPO + ethanol > TOPO + methanol > TOPO. The separation of the metal ions was discussed.

Reply to the comments of vicente et al. on ``liquid phase oxidation of p-vanillyl alcohol over synthetic co-saponite catalyst'' applied clay science (2010), doi:10.1016/j.clay.2010.10.026 - Rode, Chandrashekhar V.; Garade, Ajit C.; Biradar, Narayan S.; Kshirsagar, V. S. (Applied Clay Science, 2011)

Role of doping-induced photochemical and microstructural properties in the photocatalytic activity of InVO4 for splitting of water - Rakesh, K.; Khaire, S.; Bhange, Deu S.; Dhanasekaran, P.; Deshpande, Suvarna S.; Awate, S. V.; Gupta, N. M. (Journal of Materials Science, 2011)
We report in this paper on microstructural, optical and photocatalytic properties of single-phase indium orthovanadates, as a function of doping at lattice sites. The UV-visible spectra of these samples exhibited intense UV-region bands at 250 and 350 nm, besides broad absorption band in visible region (350-700 nm). The wavelength at absorption edge and the intensity of visible absorption showed considerable increase on doping of an impurity, particularly at V or O lattice sites. Also, the samples gave rise to blue-green photoluminescence emission, with overriding bands at ca. 420, 450, 460 and 485 nm, on excitation at 240-420 nm wavelengths. The intensity of these fluorescence bands varied with excitation wavelength and impurity content of a sample. In deviation with several earlier studies, only oxygen and no hydrogen were produced during photocatalytic splitting of water, in the experiments conducted under visible light (> 395 nm) and at a pH of similar to 6.5. The O-2 yield depended on the dispersed metal co-catalyst, impurity content and the addition of methanol as sacrificial reagent. On the other hand, small quantities of hydrogen and no oxygen were evolved on UV-irradiation of pure water using metal/InVO4. These results are ascribed to flat band potentials and the doping-induced inter-band donor and acceptor charge trapping states of InVO4, the presence of which is revealed by XRD, luminescence and XPS studies. Our study also confirms that the onset of absorption edge may not necessarily correspond to band-to-band energy gap of a semiconducting material. This accounts for some anomalous band gap energies reported earlier for InVO4.

Role of lattice defects and crystallite morphology in the UV and visible-light-induced photo-catalytic properties of combustion-prepared TiO2 - Deshpande, Aparna; Madras, Giridhar; Gupta, N. M. (Materials Chemistry and Physics, 2011)
The physico-chemical, photo-physical and micro-structural properties responsible for the strikingly different photocatalytic behavior of combustion-prepared TiO2 (c.TiO2) and Degussa P25 (d.TiO2) samples are elucidated in this study. Electron microscopy and selected area electron diffraction micrographs revealed that the two samples exhibited different morphologies. The grains of c.TiO2 were spherical and comprised of 5-6 nm size primary particle. On the other hand, d.TiO2 consisted of large (0.5-3.0 mu m) size and irregular shape aggregates having primary particles of 15-40 nm cross-sectional diameter. The ESR study revealed that the presence of certain defect states in c.TiO2 helped in stabilization of O-. and Ti3+-OH type species during room-temperature UV-irradiation. No such paramagnetic species were however formed over d.TiO2 under similar conditions. C1s and Ti 2p XPS spectra provide evidence for the presence of some lattice vacancies in c.TiO2 and also for the bulk Ti4+ -> Ti3+ conversion during its UV-irradiation. Compared to d.TiO2, c.TiO2 displayed considerably higher activity for discoloration of methyl orange but very poor activity for splitting of water, both under UV and visible light radiations. This is attributed to enhanced surface adsorption of dye molecules over c.TiO2, because of its textural features and also the presence of photo-active ion-radicals. On the other hand, the poor activity of c.TiO2 for water splitting is related to certain defect-induced inter-band charge trapping states in the close vicinity of valence and conduction bands of c.TiO2, as revealed by thermoluminescence spectroscopy. Further, the dispersion of nanosize gold particles gave rise to augmented activity of both the catalysts, particularly for water splitting. This is explained by the promotional role of Au-0 or Au-0/TiO2 interfacial sites in the adsorption and charge-adsorbate interaction processes. (C) 2011 Elsevier B.V. All rights reserved.
Keywords: Band-structure; Interfaces; Microstructure; Nanostructures; Semiconductors

Role of micro-structure and interfacial properties in the higher photocatalytic activity of TiO2-supported nanogold for methanol-assisted visible-light-induced splitting of water - Awate, S. V.; Deshpande, Suvarna S.; Rakesh, K.; Dhanasekaran, P.; Gupta, N. M. (Physical Chemistry Chemical Physics, 2011)
This paper deals with the textural, microstructural and interfacial properties of Au/TiO2 nanocomposites, in relation to their photocatalytic activity for splitting of water. TiO2 samples of two different morphologies were employed for dispersing different cocatalysts, such as: Au, Pt, Ag or Cu, for the sake of comparison. The samples were characterized using powder XRD, XPS, UV-visible, thermoluminescence, SEM, HRTEM and SAED techniques. Compared to other metal/TiO2 photocatalysts, Au/TiO2 with an optimum gold loading of 1 wt% was found to exhibit considerably higher activity for visible light induced production of H-2 from splitting water in the presence of methanol. Further, the sol-gel prepared TiO2 (s.TiO2), having spherical grains of 10-15 nm size, displayed better photoactivity than a Degussa P25 catalyst. The electron microscopy investigations on s.TiO2 revealed significant heterogeneity in grain morphology of individual TiO2 particles, exposure of the lattice planes, metal dispersion, and the interfacial metal/TiO2 contacts. The gold particles were found to be in a better dispersed state. O-2 TPD experiments revealed that the gold nanoparticles and Au/TiO2 interfaces may serve as distinct binding sites for adsorbate molecules. At the same time, our thermoluminescence measurements provide an insight into Au-induced new defect states that may facilitate the semiconductor-to-metal charge transfer transition. In conclusion, the superior photocatalytic activity of Au/TiO2 may relate to the grain morphology of TiO2, dispersion of gold particles, and the peculiar architecture of metal/oxide heterojunctions; giving rise in turn to augmented adsorption of reactant molecules and their interaction with the photo-generated e(-)/h(+) pair. The role played by methanol as a sacrificial reagent in photocatalytic splitting of water is discussed.

Role of promoters in copper chromite catalysts for hydrogenolysis of glycerol - Mane, R. B.; Ghalwadkar, Ajay A.; Hengne, Amol M.; Suryawanshi, Y. R.; Rode, C. V. (Catalysis Today, 2011)
Various copper chromite catalysts with and without promoters were prepared by simultaneous co-precipitation and digestion technique and the role of promoters (Al, Ba and Zn) was investigated for hydrogenolysis of glycerol to 1,2-propylene glycol (1,2-PG) in both batch and continuous operations. Among various promoters studied, copper chromite catalyst with Ba as a promoter showed the highest activity and selectivity of 85% to 1,2-PG. This catalyst was found to be active for more than 800 h in a continuous operation also. Ammonia TPD results showed that barium promoted copper chromite catalyst had the highest acidity which facilitates the dehydration of glycerol to acetol which is the first step in hydrogenolysis of glycerol to 1,2-PG. The effect of barium content and variation in the promoters combination was also studied. (C) 2010 Elsevier B.V. All rights reserved.
1st Joint International Conference of the 8th Tokyo Conference on Advanced Catalytic Science and Technology/5th Asia Pacific Congress on Catalysis, Sapporo, JAPAN, JUL 18-23, 2010
Keywords: 1; 2-Propylene glycol; Acetol; Ammonia TPD; Glycerol hydrogenolysis; Surface acidity

Selective hydrogenation of chloronitrobenzenes with an MCM-41 supported platinum allyl complex derived catalyst - Indra, Arindam; Rajamohanan, Pattuparambil R.; Gopinath, Chinnakonda S.; Bhaduri, Sumit; Lahiri, Goutam Kumar (Applied Catalysis A-General, 2011)
A platinuin precatalyst (1) has been prepared by reacting [(eta(3)-C3H5)(4)Pt4Cl4] with surface functionalized MCM-41 with pendant -(CH2)(3)NH(CH2)(2)NH2 groups. For the hydrogenation of o-, m- and p-chloronitrobenzenes to the corresponding chloroanilines, 1 is found to be a highly active catalyst with good selectivities for them-and p-isomers. Its performance is superior to that of its palladium analogue and far superior to that of commercial (5%) Pt/C or (5%) Pt/Al2O3. Comparison of solid state and solution NMR data and other evidences indicate that on treatment with the functionalized MCM-41 support; [(eta(3)-C3H5)(4)Pt4Cl4] loses the ally! ligand. XPS data show that in the fresh catalyst Pt is present in the 2+ oxidation state. Based on these and analytical data, co-ordination by surface diamine and hydroxo groups to Pt2+ in 1 is suggested. In the used catalyst both Pt2+ and Pt are present but the amount of metallic platinum is similar to 16% of the total. (C) 2011 Elsevier B.V. All rights reserved.
Keywords: Chloronitrobenzenes; Dehydrohalogenation; heterogeneous catalyst; MCM-41; Selective hydrogenation

Self-standing three-dimensional networks of nanoparticles with controllable morphology by dynamic templating of surfactant hexagonal domains - Sharma, Kamendra P.; Ganai, Anal Kumar; Sen Gupta, Sayam; Kumaraswamy, Guruswamy (Chemistry of Materials, 2011)
Assembly of nanoparticles into free-standing three-dimensional networks has implications for a wide range of applications. We show that dynamic templating of surfactant hexagonal domains is a facile technique to organize nanoparticles into a network of particulate strands. Dispersed particles (> 10 nm), independent of particle chemistry, assemble into networks, when the surfactant matrix cools into the hexagonal phase. We demonstrate assembly of inorganic, polymeric, and protein nanoparticles into networks. Where particle assembly is reversible, particles are coated with polymers that are subsequently cross-linked to stabilize the networks after surfactant removal. This technique involves near ambient temperatures and a benign water wash for template removal. The network mesh size can be varied from submicrometers to tens of micrometers by controlling the cooling rate. Particle networks can be flow-oriented prior to cross-linking, and interpenetrating networks can also be formed.
Keywords: hexagonal; macroporous; nanoparticle; self assembly; surfactant

Shape preserving chemical transformation of ZnO mesostructures into anatase TiO2 mesostructures for optoelectronic applications - Muduli, Subas; Game, Onkar S.; Dhas, Vivek V.; Yengantiwar, Ashish; Ogale, Satishchandra B. (Energy & Environmental Science, 2011)
In this work we report on the synthesis of various ZnO mesostructures (rods, spheres, flakes and flower-like morphologies) by hydrothermal and co-precipitation methods and their remarkable and complete transformation into anatase TiO2 mesostructures with nominally similar shapes using controlled low temperature TiCl4 treatment. Various techniques are used to demonstrate the phase purity and morphology details. Based on the careful examination of the transformation of ZnO rods into TiO2 tubes we suggest a mechanism which embodies initial formation of a thin TiO2 shell on the ZnO surface by ion exchange (Ti4+-Zn2+) followed by Zn diffusion through the shell and its oxidation on the surface. We used these converted TiO2 mesostructures for light harvesting in Dye Sensitized Solar Cells (DSSCs) to enhance the conversion efficiency. It is shown that DSSCs made using a doctor bladed film of TiO2 nanoparticles with an overlayer of TiCl4 treated ZnO flowers yield a solar cell efficiency of 6.9% which is considerably higher than that with only TiO2 nanoparticle film (5.4%) of comparable thickness.

Solvent-free mukaiyama-aldol condensation catalyzed by Ce-Al-MCM-41 mesoporous materials - Kalita, Pranjal; Gupta, Narendra M.; Kumar, Rajiv (Microporous and Mesoporous Materials, 2011)
MCM-41 samples containing Ce4+ and Al3+ in the network, designated as Ce-x-Al-MCM-41 (x = 0.0-0.04), were synthesized and characterized systematically. These samples exhibited higher catalytic activity for Mukaiyama-aldol condensations to produce beta-hydroxy carbonyl compounds under the solvent free conditions, compared to the samples containing either of the two cations. The product yield was found to depend on the electron donating/withdrawing characteristics of reactant molecules being responsible for the observed trend. Series of solvents were also investigated but considerably high yield of aldol products (similar to 95%) could be achieved without using any solvents. In all the cases, the selectivity was found to be 100%, typical of such Mukaiyama-aldol condensations. The higher catalytic activity of Ce-x-Al-MCM-41 is explained on the basis of certain new acid sites generated due to co-incorporation of Ce and Al cations. Published by Elsevier Inc.
16th IZC/7th IMMS Conference, Sorrento, ITALY, JUL 04-09, 2010
Keywords: Acid catalyst; Ce-Al-MCM-41; Silyl enol ether and aldehyde; Silyl ketene acetal

Stereoselective synthesis of ophiocerins A and C - Show, Krishanu; Gupta, Priti; Kumar, Pradeep (Tetrahedron-Asymmetry, 2011)
An efficient synthesis of ophiocerins A and C has been achieved via a common intermediate. The stereogenic centers were generated by means of Jacobsen's hydrolytic kinetic resolution and Sharpless kinetic resolution. (C) 2011 Elsevier Ltd. All rights reserved.

Strain improvement and statistical media optimization for enhanced erythritol production with minimal by-products from candida magnoliae mutant R23 - Savergave, Laxman S.; Gadre, Ramchandra V.; Vaidya, Bhalchandra K.; Narayanan, Karthik (Biochemical Engineering Journal, 2011)
Mutants of Candida magnoliae NCIM 3470 were generated by ultra-violet and chemical mutagenesis to enhance erythritol production. The mutants were screened for higher reductase activity on agar plates containing high concentration of glucose and 2,3,5-triphenyl tetrazolium chloride (TTC). One of the mutants named as R23 gave maximum erythritol production, 60.3 g L(-1), compared to 14 g L(-1) of the parent strain. Glucose and yeast extract were identified as critical medium components which decide the ratio of polyols produced, mainly erythritol, mannitol and glycerol. In order to enhance the production of erythritol and to minimize the production of mannitol and glycerol, a four component-five level-three response central-composite-rotatable-design (CCRD) of response surface methodology (RSM) model was used. The optimum medium composition for erythritol production was found to contain (g L(-1)) glucose 238, yeast extract 9.2, KH(2)PO(4), 5.16 and MgSO(4) 0.23. Moreover, erythritol production was studied in a 10 L fermentor in batch and fed-batch mode using RSM optimized medium. In fed-batch fermentation, 87.8 g L(-1) erythritol was produced with 31.1% yield, without formation of any other polyols. Thus present study involving strain improvement followed by media and process optimization resulted in 6.2-fold increase in erythritol production and 3.4-fold increase in the yield. (C) 2011 Elsevier B.V. All rights reserved.
Keywords: Candida magnoliae; Erythritol; Fermentation; Metabolite over-production; Modelling; Optimization

Strong photo-response in a flip-chip nanowire p-Cu2O/n-ZnO junction - Deo, Meenal S.; Mujawar, Sarfraj; Game, Onkar S.; Yengantiwar, Ashish; Banpurkar, Arun G.; Kulkarni, Sneha; Jog, Jyoti Prakash; Ogale, Satishchandra B. (Nanoscale, 2011)
Cu2O nanoneedles are synthesized on a copper substrate by a simple anodization and reducing ambient annealing protocol. ZnO nanorods are grown on ITO coated glass by a low temperature chemical route. The electronic and photo-response properties of the p-Cu2O/n-ZnO flip-chip heterojunction are then studied and analyzed. We show that the I-V characteristic is rectifying and the junction exhibits a good photoresponse (similar to 120% under 1 V reverse bias) under AM 1.5 (1 Sun) illumination. This nano-heterojunction photo-response is far stronger as compared to that of a pulsed laser deposited thin film p-Cu2O/n-ZnO heterojunction, which can be attributed to higher junction area in the former case.

Studies on the feasibility of recycled polystyrene doped with NLO active meta-Nitroaniline for optoelectronics applications - Sureshkumar, M. S.; Goyal, R. K.; Negi, Y. S.; Pratheepkumar, A.; Reddy, K. Raghunatha; Singh, R. P.; Dadge, Jagdish W.; Aiyer, Rohini C. (Polymers for Advanced Technologies, 2011)
A Guest-Host system based on meta-Nitroaniline (m-NA) and recycled polystyrene (RPS) susceptible to generate nonlinear optically (NLO) active property such as second harmonic generation (SHG) has been prepared. Pure, sublimed, optical grade, crystalline m-NA is used as a guest and RPS from the disposable packaging waste as available utilized as the host polymer. In this paper we report the effect of NLO active m-NA on the bulk and optical properties of RPS. The purified m-NA was incorporated from 1-10 wt% in the RPS polymer matrix by conventional solution casting method. Thin, transparent, freestanding films obtained were characterized with optical microscope, scanning electron microscope (SEM), viscosity measurement, and UV-Visible (UV-Vis) spectroscopy for bulk properties evaluation and Nd:YAG laser studies for optoelectronics application such as SHG through frequency doubling. Copyright (C) 2010 John Wiley & Sons, Ltd.
Keywords: frequency doubling; guest-host NLO systems; meta-Nitroaniline; nonlinear optical activity; Polystyrene; second harmonic generation

Synthesis and application of a chiral diborate - Loewer, Yvonne; Weiss, Christine; Biju, Akkattu T.; Frohlich, Roland; Glorius, Frank (Journal of Organic Chemistry, 2011)
A chiral diborate with different counterions is reported whose structure was unambiguously confirmed by X-ray analysis. This chiral dianion was used in the resolution of trans-1,2-diamines and also as a chiral shift reagent for NMR analysis of triphenylphosphonium salts.

Synthesis and characterization of bile acid-based poly beta amino esters for paclitaxel delivery - Gangwal, Jitendra J.; Kulkarni, Mohan G. (Journal of Applied Polymer Science, 2011)
New biodegradable poly beta amino esters were synthesized by the polymerization of Deoxycholic acid (DOCA) in all the structural planes by 1, 4 addition of Trimethylene dipiperidine (TMDP) to diacrylates of Deoxycholyl glycol, Methyl deoxycholate and Trimethylolpropane deoxycholate esters. H-1-NMR, C-13-NMR and IR studies confirmed presence of amine and Deoxycholyl units in polymers. XRD and TGA studies indicated that all the polymers were amorphous and thermostable up to 300 degrees C. DSC studies revealed glass transition temperature (T-g) in the range 70-80 degrees C. All the polymers degraded very slowly in the buffers of pH 1.1, 7.4 and 10 because of the hydrophobic nature of Deoxycholate units. These polymers also exhibited pH sensitivity due to the incorporation of amines along with Deoxycholate units in the backbone. P-Nitroaniline (PNA) release followed anomalous release kinetics. Paclitaxel (PTX) loaded nanospheres prepared from these polymers were spherical and uniform in the size range 75-250 nm and 0.4-1 mu depending upon the method of preparation. PTX loading was in the range 60-90%, while release (up to 20-60%) was sustained over a period of 100 h. (c) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 220-232, 2011
Keywords: bile acid; biodegradable; Nanoparticles; Paclitaxel; poly beta amino esters

Synthesis and characterization of CdS/PVA nanocomposite thin films from a complexing agent free system - Saikia, Dulen; Saikia, P. K.; Gogoi, P. K.; Das, M. R.; Sengupta, P.; Shelke, M. V. (Materials Chemistry and Physics, 2011)
CdS/PVA nanocomposite thin films have been deposited on glass substrates by in situ thermolysis of precursors dispersed in polyvinyl alcohol (PVA). The synthetic technique reported in this study is free from complexing agent and hence no need to control the pH of the solution as in the case of conventional CBD. The as-prepared films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), UV-vis spectroscopy, and photoluminescence (PL) spectra. The XRD and SAED results indicated the formation of CdS nanoparticles with hexagonal phase in the PVA matrix. The photoluminescence and UV-vis spectroscopy revealed that CdS/PVA films showed quantum confinement effect. From the shift in optical band gap, particle sizes were calculated using effective mass approximation (EMA) method and it was found to be in agreement with the results obtained from TEM observations. The SEM results indicated that as grown films were homogeneous with no visible pinholes and cracks. The film prepared at 100 degrees C was found to be suitable for application as a window layer in solar cell. (C) 2011 Elsevier B.V. All rights reserved.
Keywords: CdS/PVA; Nanocomposite; Optical properties; Thermolysis

Synthesis and characterization of poly-L-lysine grafted SBA-15 using NCA polymerization and click chemistry - Kar, Mrityunjoy; Malvi, Bharmana; Das, Anindita; Panneri, Suyana; Sen Gupta, Sayam (Journal of Materials Chemistry, 2011)
Poly-L-lysine (PLL) grafted ordered mesoporous material was prepared by a combination of NCA polymerization and click chemistry. Large pore SBA-15 with a mesopore diameter of similar to 12 nm was synthesized using a previously reported method. The surface of this SBA-15 material was modified with azidopropyl groups. This ``clickable'' SBA-15 was then reacted with an alkyne terminated poly-L-lysine synthesized by the ring-opening polymerization of 3-cbz-L-lysine NCA with N-TMS propargylamine as the initiator. This procedure allows grafting of a uniform polymer film with a high polymer loading. No appreciable pore blocking was observed upon grafting of PLL. No change in the periodic structure of the SBA-15 was observed throughout the grafting process. The SBA-15 PLL conjugate was characterized using (13)C and (29)Si NMR, XRD, FT-IR, N(2) adsorption-desorption and thermogravimetry. The results indicate that polypeptides can be easily grafted onto various ordered mesoporous materials by this ``grafting to'' methodology with accessible pores and high loadings of the polypeptide.

Synthesis and characterization of thermo-sensitive graft copolymer of carboxymethyl guar and poly(N-isopropylacrylamide) - Gupta, Nivika R.; Ghute, Pallavi P.; Badiger, Manohar V. (Carbohydrate Polymers, 2011)
Thermo-responsive graft copolymers of carboxymethyl guar [CMG] and semitelechelic poly(N-isopropylacrylamide) [PNIPAm] were synthesized by coupling reaction between them using a water-soluble coupling agent namely, 1-(3-(dimethylamino) propyl)-3-ethyl carbodiimide hydrochloride [EDC]. The incorporation of PNIPAm into CMG was confirmed by FT-IR and NMR spectroscopy. The graft copolymers, CMG-g-PNIPAm showed enhanced viscosity as compared to the unmodified CMG in the semi-dilute regime. Due to the presence of a LCST side chains [PNIPAm], the graft copolymers exhibited thermo-responsive nature with respect to temperature which was investigated using pyrene fluorescence probe studies. Although the thermo-responsive property was observed, the thermo-thickening behavior was not seen in these polymers. The graft copolymers in the semi-dilute regime (C(p) approximate to 10-20 g/L) showed viscoelastic properties and the relaxation time, tau, could be obtained from the crossover of frequency (oh) of storage modulus (G') and loss modulus (G `') in the oscillatory experiments. The activation energy `E(a)' of associations was investigated using the time temperature superpsition (TTS). These thermo-responsive polymers along with the biodegradability of CMG can have potential application as industrial thickening agent. (C) 2010 Elsevier Ltd. All rights reserved.
Keywords: Carboxymethyl guar; Poly(N-isopropylacrylamide); Thermo-sensitivity and graft copolymer

Synthesis and structural characterization of a solvated dimorph of a hydrazonato-oxovanadium(v) complex with [OV(mu-O)VO] core - Mondal, Bipul; Banerjee, Rahul; Ghosh, Tapas (Journal of the Indian Chemical Society, 2011)
In this paper we report the synthesis and structural characterization of a different monoclinic variety of the title complex [V2O3(L)(2)], incorporating the doubly deprotonated benzoyl hydrazone of 5-chloro-2-hydroxyacetophenone (H2L) with P2(1)/c space group that showed some differences in bonding patterns in the solid state with respect to its another monoclinic variety with C2/c space group reported earlier.
Keywords: crystal structure; dimorphism; hydrazone complex; Oxovanadium(v) complex

Synthesis, electronic structure, DNA and protein binding, DNA cleavage, and anticancer activity of fluorophore-labeled copper(II) complexes - Bhat, Satish S.; Kumbhar, Anupa A.; Heptullah, Hussain; Khan, Ayesha A.; Gobre, Vivekanand V.; Gejji, Shridhar P.; Puranik, Vedavati G. (Inorganic Chemistry, 2011)
Two mononuclear fluorophore-labeled copper(II) complexes [Cu(nip)(acac)](+) (2) and [Cu(nip)(2)](2+) (3), where fluorophore is 2-(naphthalen-1-yl)-1H-imidazo[4,5-f][1,10]phenanthroline (nip) (1) and acac is acetylacetone, have been synthesized aid characterized by various techniques. The ligand 1 and complex 2 are structurally characterized by single-crystal X-ray diffraction. The coordination geometries around the copper are square planar in solid as well as solution state as evidenced by electron paramagnetic resonance (EPR) spectroscopy. The density functional calculations carried out on 1-3 have shown that electron-rich regions in the highest occupied orbital are localized on the naphthalene end partly on the phenanthroline moiety. Both complexes 2 and 3 in dimethyl sulfoxide (DMSO) exhibit near square planar structure around the metal ion in their ground state. Time-dependent density functional theory (TD-DFT) calculations reveal that Cu(II) ion in complex 2 shows tetrahedral coordination around the metal while 3 retains its square planar geometry in the lowest excited state. The interaction of complexes with calf-thymus DNA (CT DNA) has been explored by using absorption, emission, thermal denaturation, and viscosity studies, and the intercalating mode of DNA binding has been proposed. The complexes cleave DNA oxidatively without any exogenous additives. The protein binding ability has been monitored by quenching of tryptophan emission in the presence of complexes using bovine serum albumin (BSA) as model protein. The compounds showed dynamic quenching behavior. Further, the anticancer activity of the complexes on MCF-7 (human breast cancer), HeLa (human cervical cancer), HL-60 (human promyelocytic leukemia), and MCF-12A (normal epithelial) cell lines has been studied. It has been observed that 3 exhibits higher cytotoxicity than 2, and the cells undergo apoptotic cell death.

Synthesis of cube-shaped gold nanostructures by electron irradiation - Dhumale, Vinayak A.; Gangwar, Rajesh K.; Shah, Preeti V.; Bhoraskar, Vasant N.; Mulla, Imtiaz S.; Sharma, Rishi B. (Materials Letters, 2011)
The needle-like gold nanostructures were synthesized by using chloroauric acid (HAuCl(4)) as a metal precursor and sodium borohydride (NaBH(4)) as the reducing agent. These needle-like nanostructures of gold were irradiated with high energy electrons (E-6 MeV, phi similar to 10(12) e cm(-2) s(-1)). The pre- and post-irradiated gold nanostructures were characterized by Scanning Electron Microscopy (SEM), UV-vis spectroscopy, X-ray Diffraction (XRD) and contact angle measurement (GBX-Model Digidrop) techniques. The results of the SEM revealed that after electron irradiation, the needle-like gold structures got fragmented into identical cube-shaped gold nanostructures, though of different sizes. The XRD analysis indicated that the average crystallite size of the gold nanostructures remained unchanged even after irradiation with high energy electrons. A glass surface showed hydrophilic behavior when coated with needle-like nanostructures and became ultra hydrophilic when coated with cube-shaped gold nanostructures. (C) 2011 Elsevier B.V. All rights reserved.
Keywords: Gold nanostructures; High energy electron irradiation; Nanostructured materials; Radiation damage; Surfaces; Ultra hydrophilic surfaces

Synthesis of glycopolypeptides by the ring opening polymerization of O-glycosylated-alpha-amino acid N-carboxyanhydride (NCA) - Pati, Debasis; Shaikh, Ashif Y.; Hotha, Srinivas; Sen Gupta, Sayam (Polymer Chemistry, 2011)
The novel synthesis of O-glycosylated lysine-NCA from a stable glycosyl donor and a commercially available protected amino acid in very high yield is reported. These O-glycosylated lysine-NCA monomers underwent ring opening polymerization using simple primary amine initiators to form well defined, high molecular weight homoglycopolypeptides and diblock co-glycopolypeptides. The synthesis of azide labelled end functionalized glycopolypeptides and amphiphilic diblock copolypeptides is also reported. This methodology represents an easy and practical route to the synthesis of O-glycosylated polypeptides with 100% glycosylation.

Synthesis of peptides and pyrazines from beta-aminoalcohols via extrusion of H2 catalyzed by ruthenium pincer complexes. ligand controlled selectivity - Gnanaprakasam, Boopathy; Balaraman, Ekambaram; Ben-David, Yehoshoa; Milstein, David (Angewandte Chemie, 2011)
Bitte wählen: Die Wahl des Katalysators, eines Ru-Pinzettenkomplexes, bestimmt, ob Peptide oder Pyrazine aus β-Aminoalkoholen entstehen: Der PNN-Komplex 1 führt, je nach Substituent R (siehe Schema), zu linearem Polyalanin oder zu cyclischen Dipeptiden, der PNP-Komplex 2 katalysiert die Bildung von Pyrazinen. Die Reaktionen finden in homogener Lösung unter neutralen Bedingungen statt.

Synthesis of poly-L-glutamic acid grafted silica nanoparticles and their assembly into macroporous structures - Kar, Mrityunjoy; Pauline, Minois; Sharma, Kamendra; Kumaraswamy, Guruswamy; Sen Gupta, Sayam (Langmuir, 2011)
Polypeptide-coated silica nanoparticles represent an interesting class of organic inorganic hybrids since the ordered secondary structure of the polypeptide grafts imparts functional properties to these nanoparticles. The synthesis of a poly-L-glutamic acid (PLGA) silica nanoparticle hybrid by employing N-carboxyanhydride (NCA) polymerization to synthesize the polypeptide chains and Cu catalyzed azide alkyne cycloaddition reaction to graft these chains onto the silica surface is reported. This methodology enables the synthesis of well-defined polypeptide chains that are attached onto the silica surface at high surface densities. The PLGA-silica conjugate particles are well dispersed in water, and have been thoroughly characterized using multinuclear (C-13, Si-29) solid state NMR, thermogravimetric analysis, Fourier transform infrared, dynamic light scattering, and transmission electron microscopy. The pH-dependent reversible aggregation of the PLGA-silica particles, driven by the change in PLGA structure, has also been studied. Preliminary results on the use of aqueous dispersions of silica-PLGA for the preparation of three-dimensional macroporous structures with oriented pores by ice templating methodology are also demonstrated. These macroporous materials, comprising a biocompatible polymer shell covalently attached to rigid inorganic cores, adopts an interesting lamellar structure with fishbone-type architecture.

Systems view of the protein expression process - Gokhale, Sucheta A.; Nyayanit, Dimpal; Gadgil, Chetan J. (Systems and Synthetic Biology, 2011)
Many biological processes are regulated by changing the concentration and activity of proteins. The presence of a protein at a given subcellular location at a given time with a certain conformation is the result of an apparently sequential process. The rate of protein formation is influenced by chromatin state, and the rates of transcription, translation, and degradation. There is an exquisite control system where each stage of the process is controlled both by seemingly unregulated proteins as well as through feedbacks mediated by RNA and protein products. Here we review the biological facts and mathematical models for each stage of the protein production process. We conclude that advances in experimental techniques leading to a detailed description of the process have not been matched by mathematical models that represent the details of the process and facilitate analysis. Such an exercise is the first step towards development of a framework for a systems biology analysis of the protein production process.

Target cum flexibility: an alkyne [2+2+2]-cyclotrimerization strategy for synthesis of trinem library - Ramana, C. V.; Dushing, Mangesh P.; Mohapatra, Sradhanjali; Mallik, Rosy; Gonnade, Rajesh G. (Tetrahedron Letters, 2011)
A rapid access to the central 4,5,6-tricyclic core of 4,5,6-trinems has been achieved by employing the alkyne [2+2+2]-cyclotrimerization as the key and final reaction in the synthesis. (C) 2010 Elsevier Ltd. All rights reserved.

Thermal epimerization of inositol 1,3-benzylidene acetals in the molten state - Gurale, Bharat P.; Krishnaswamy, Shobhana; Vanka, Kumar; Shashidhar, Mysore S. (Tetrahedron, 2011)
1,3-O-Benzylidene-2,4,5,6-tetra-O-substituted-myo-inositol derivatives obtained by the DIBAL-H reduction of the corresponding myo-inositol 1,3,5-orthobenzoate derivatives undergo epimerization at the acetal carbon on heating, in the molten state, just above their melting point. The same epimerization reaction does not proceed either in the crystalline state or in solution. DFT calculations suggest that the epimeric acetal obtained by this thermal process is relatively more stable than the starting acetal. Either of these acetals could not be obtained by the reaction of the corresponding inositol derived diol with benzaldehyde. These observations constitute a novel reaction solely in the molten state, which are rarely encountered in the literature. X-ray crystal structures of the epimeric acetals as well as their radical deoxygenation reaction are also reported. (C) 2011 Elsevier Ltd. All rights reserved.
Keywords: cyclitols; Deoxygenation; Epimerization; Melt; Xanthate

To make polymer: quantum dot hybrid solar cells NIR-active by increasing diameter of PbS nanoparticles - Guchhait, Asim; Rath, Arup Kumar; Pal, Amlan J. (Solar Energy Materials and Solar Cells, 2011)
We fabricate NIR-active solar cells based on PbS quantum dots and a conventional conjugated polymer. These devices act as solar cells under exclusively NIR wavelengths above 650 nm. Here PbS nanoparticles absorb photons in the NIR range that in turn generate excitons. We show that with an assistance from a strong electron-acceptor (TiO2), these excitons can be dissociated to electrons and holes to yield a photocurrent in the external circuit. We then aim to extend the spectral window of the solar cells to higher wavelength region by increasing the diameter of PbS nanoparticles to make the cells further NIR-active. We observe that the short-circuit current (JSC) shows a peak when the diameter of PbS nanoparticles increases. Here, the spectral window can be extended till conduction band-edge of PbS quantum dots falls below that of TiO2 nanostructures cutting off the electron-transfer pathway. The NIR-active photovoltaic solar cells yield a short-circuit current (JSC) of 1.0 mA/cm2, open-circuit voltage (VOC) of 0.42 V, and power conversion efficiency (η) of 0.16% and remain operative till 1200 nm.

Toward an understanding of the molecular level properties of ziegler-natta catalyst support with and without the internal electron donor - Thushara, K. S.; Gnanakumar, Edwin S.; Mathew, Renny; Jha, Ratnesh Kumar; Ajithkumar, Thalasseril G.; Rajamohanan, P. R.; Sarma, Krishna; Padmanabhan, Sudhakar; Bhaduri, Sumit; Gopinath, Chinnakonda S. (Journal of Physical Chemistry C, 2011)
Two Ziegler-Natta catalysts supported on molecular adducts, namely, MgCl2 center dot 6EtOH (ME) and MgCl2 center dot 5EtOH center dot EtOOCPh (Est-ME), have been prepared. A systematic effort has been made to unravel the molecular level structure property relationships of the catalysts and adducts. Ethylbenzoate is an internal electron donor, and its in situ formation through EtOH+PhCOCl coupling is successfully achieved. The above adduct has been treated with TiCl4, and the resultant catalyst (Ti/Est-ME) is evaluated for ethylene polymerization activity. Rand C-13 CP/MAS NMR of Est-ME (Ti/Est-ME) show carbonyl features at 1730 (1680) cm(-1) and 169 (170) delta, respectively, providing direct support for the presence of ester as an integral part. In spite of low surface area, Ti/Est-ME gives higher yield for ethylene polymerization than the one derived from ME. The results indicate that electronic environment is more important than surface area or any other single factor in determining the polymerization activity.

Transport of carbonate ions through supported liquid membrane by using Alamine 336 and trioctylphosphine oxide as carriers - Gaikwad, Abaji G. (Green Chemistry Letters and Reviews, 2011)
Transport studies were carried out for carbonate ions through supported liquid membrane (SLMs) by sing Alamine 336 and trioctylphosphine oxide (TOPO) as carriers. Experimental variables were investigated, such as concentration of carbonate ion (10(-5) to 4 x 10(-2) M), carriers (10(-5) to 10(-1) M), and alkali (0.01-0.5); and stirring speed (50-50 rpm) of bulk solutions. The use of combined carriers Alamine 336 and TOPO shows a synergic transport of carbonate ions. The stability of the SLM system in relation to the transport of carbonate ions has been studied. The enrichment of carbonate ions (10(-6) to 4 x 10(-2) M) from the dilute solution was explored. The different combinations of amines with TOPO show synergic permeability of the carbonate ions through SLM system.
Keywords: Alamine 336; carbonate ion; supported liquid membrane; synergic effect; trioctyl phosphine oxide (TOPO)

Transport of indium, gallium and thallium metal ions through chromatographic fiber supported solid membrane in acetylacetone containing mixed solvents - Gaikwad, Abaji G. (Chinese Journal of Chemical Engineering, 2011)
The transport of metal ions of indium, gallium and thallium from source solution to receiving phase through the chromatographic fiber supported solid membrane in the acetylacetone (HAA) containing mixed solvent system has been explored. The fibers supported solid membranes were prepared with chemical synthesis from cellulose fibers and citric acid with the carboxylic acid ion exchange groups introduced. The experimental variables, such as concentration of metal ions (10(-2) to 10(-4) mol.L(-1)) in the source solution, mixed solvent composition [for example, acetylacetone, (2,4-pentanedione), (HAA) 20% (by volume), 1,4-dioxane 10% to 60% and HCl 0.25 to 2 mol.L(-1)] in the receiving phase and stirring speed (50-130 r.min(-1)) of the bulk source and receiving phase, were explored. The efficiency of mixed solvents for the transport of metal ions from the source to receiving phase through the fiber supported solid membrane was evaluated. The combined ion exchange solvent extraction (CIESE) was observed effective for the selective transport of thallium, indium and gallium metal ions through fiber supported solid membrane in mixed solvents. The oxonium salt formation in the receiving phase enhances thallium, indium and gallium metal ion transport through solid membrane phase. The selective transport of thallium metal ions from source phase was observed from indium and gallium metal ions in the presence of hydrochloric acid in organic solvents in receiving phase. The separation of thallium metal ions from the binary mixtures of Be(II), Ti(IV), Al(III), Ca(II), Mg(II), K (I), La(III) and Y(III) was carried out in the mixed solvent system using cellulose fiber supported solid membrane.
Keywords: acetylacetone; extraction; fiber supported solid membrane; metal ions transfer; stripping

Transport of metal ions through cellulose fiber supported solid membrane into tributyl phosphate containing mixed solvents - Gaikwad, Abaji G. (Chemical and Biochemical Engineering Quarterly, 2011)
A novel cation exchange fiber supported solid membrane was developed for transport of cobalt, manganese and nickel metal ions. Fiber supported solid membrane was prepared by chemically modifying the cellulose fibers with citric acid. In the fiber supported solid membrane, the diffusion by capillary action by keeping the liquid phase in the porous solid fiber and ion exchange mechanism were used for the effective transport of metal ions. The experimental variables examined were concentration of metal ions (10(-2) to 10(-4) mol L-1) in the source solution, mixed solvent composition (phi = 20 % TBP, acetone or tetrahydrofuran or 1,4-dioxane or methanol or ethanol or 2-propanol 10 to 60 % and HCl (1 to 2 mol L-1) in the receiving phase and stirring speed (40-120 rpm) of the bulk source and receiving phase. The enrichment of concentration of cobalt, manganese and nickel metal ions was observed from the dilute solutions.
Keywords: binary of mixtures of metal ions; cobalt; extraction; fiber supported solid membrane; ion exchange; manganese and nickel metal ions; stripping

Transport of metal ions through fiber supported solid membranes in mixed solvents - Gaikwad, Abaji G. (Fibers and Polymers, 2011)
The transport of metal ions has been explored of bismuth, cadmium and lead from source solution to receiving phase through the fiber supported solid membrane system. The fibers supported solid membranes were prepared by chemically modification of cellulose fibers with the introducing the ion exchanging groups. The experimental variables explored were concentration of metal ions in the source solution, mixed solvent composition in the receiving phase and stirring speed of the bulk source solution and receiving phase. The efficiency has been evaluated for the transport of metal ions from the source to receiving phase through the fiber supported solid membrane. The pre-concentration was investigated of metal ions from the dilute solutions. The fiber supported solid membrane with two-channel systems had been investigated for the transport of metal ions from the source to receiving phase. The capillary action phenomenon helps to effectively transport the metal ions through the fiber supported solid membrane.
Keywords: binary of mixtures of metal ions; Bismuth; Cadmium and lead metal ions; extraction; fiber supported solid membrane; ion exchange; stripping

Urea/thiourea derivatives and Zn(II)-DPA complex as receptors for anionic recognition-a brief account - Das, Priyadip; Mahato, Prasenjit; Ghosh, Amrita; Mandal, Amal Kumar; Banerjee, Tanmay; Saha, Sukdeb; Das, Amitava (Journal of Chemical Sciences, 2011)
This review covers few examples of anion complexation chemistry, with a special focus on urea/thiourea-based receptors and Zn(II)-dipicolyl amine-based receptors. This article specially focuses on structural aspects of the receptors and the anions for obtaining the desire specificity along with an efficient receptor–anion interaction. Two types of receptors have been described in this brief account; first one being the strong hydrogen bond donor urea/thiourea derivatives, which binds the anionic analytes through hydrogen bonded interactions; while, the second type of receptors are coordination complexes, where the coordination of the anion to the metal centre. In both the cases the anion binding modulate the energy gap between the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) and thereby the spectroscopic response. Appropriate choice of the signalling unit may allow probing the anion binding phenomena through visual detection.

What drives the redox properties of model green fluorescence protein chromophores? - Solntsev, Kyril M.; Ghosh, Debashree; Amador, Adrian; Josowicz, Mira; Krylov, Anna I. (Journal of Physical Chemistry Letters, 2011)
We report the first experimental determination of the oxidation potentials E-ox(0). (relative to the standard hydrogen electrode, SHE) of model green fluorescent protein (GFP) chromophores. Para-, meta, and ortho-hydroxy (4-hydroxybenzylidene-2,3-dimethylimidazolinone, HBDI) and methoxy (MeOBDI) derivatives were studied. E-ox(0) of the three isomers in acetonitrile are -1.31, -1.52, and -1.39 V, respectively. Electronic structure calculations reproduce the observed differences between the isomers and reveal that E-ox(0) follows the ionization energies (IEs), that is, p-MeOBDI has the lowest IE (6.96 eV in the gas phase) due to resonance stabilization of its cation, whereas the resonance is detuned in m-MeOBDL resulting in more-negative E-ox(0). The observed meta and ortho effects in E-ox(0) are similar to the trends in pK(a). The effect of increased solvent polarity on absolute.E-ox(0) (and especially on para-meta-ortho differences) was found to be small. The redox properties of GFP chromophores are driven by their structure and can be correlated with IEs, which can be exploited in predicting the properties of other fluorescent protein chromophores.

ZnII-2,2?:6?,2?-terpyridine-based complex as fluorescent chemosensor for PPi, AMP and ADP - Das, Priyadip; Ghosh, Amrita; Kesharwani, Manoj K.; Ramu, Vadde; Ganguly, Bishwajit; Das, Amitava (Europian Journal of Inorganic Chemistry, 2011)
A new ZnII–2,2′:6′,2″-terpyridine complex, derivatized with a coumarin moiety (L1Zn), acts as a fluorescent chemosensor for different biologically important phosphates like PPi, AMP and ADP in mixed aqueous media. Depending on the proportion of the aqueous fraction present in the solvent mixture, L1Zn shows a preference for different phosphate moieties at physiological pH. In an aqueous acetonitrile (2:3, v/v) medium this reagent shows a preference for AMP as compared to ADP, ATP and PPi. The binding affinities of L1Zn with different phosphate ions and associated shifts in the electronic spectra were rationalized by DFT calculations. Such an example of a receptor that is selective for AMP under physiological conditions is rare in the literature.

Zn(II)-cyclam based chromogenic sensors for recognition of atp in aqueous solution under physiological conditions and their application as viable staining agents for microorganism - Mahato, Prasenjit; Ghosh, Amrita; Mishra, Sanjiv K.; Shrivastav, Anupama; Mishra, Sandhya; Das, Amitava (Inorganic Chemistry, 2011)
Two chromogenic complexes, L.Zn (where L is (E)-4-((4-(1,4,8,11-tetraazacyclotetradecan-1-ylsulfonyl)phenyl)diazenyl)-N,N-dimethylaniline) and its [2]pseudorotaxane form (α-CD.L.Zn), were found to bind preferentially to adenosine triphosphate (ATP), among all other common anions and biologically important phosphate (AMP, ADP, pyrophosphate, and phosphate) ions in aqueous HEPES buffer medium of pH 7.2. Studies with live cell cultures of prokaryotic microbes revealed that binding of these two reagents to intercellular ATP, produced in situ, could be used in delineating the Gram-positive and the Gram-negative bacteria. More importantly, these dyes were found to be nontoxic to living microbes (eukaryotes and prokaryotes) and could be used for studying the cell growth dynamics. Binding to these two viable staining agents to intercellular ATP was also confirmed by spectroscopic studies on cell growth in the presence of different respiratory inhibitors that influence the intercellular ATP generation.

1-Benzoyl-3-[(2-benzylsulfanyl)phenyl]thiourea - Bhattacharjee, Tirtha; Gogoi, Prasanta; Puranik, Vedavati G.; Gawade, Rupesh L.; Barman, Pranjit (Acta Crystallographica Section C-Crystal Structure Communications, 2012)
In the title compound, C21H18N2OS2, a strong intramolecular N-H center dot center dot center dot O hydrogen bond [N center dot center dot center dot O = 2.642 (3) angstrom] between the amide N atom and the benzoyl O atom forms an almost planar six-membered ring in the central part of the molecule. In the crystal, molecules are packed through weak N-H center dot center dot center dot S interactions. Intra- and intermolecular hydrogen bonds and van der Waals interactions are the stabilizing forces for the crystal structure.

4(R/S)-Amino/guanidino-substituted proline peptides: design, synthesis and DNA transfection properties - Umashankara, M.; Nanda, Manaswini; Sonar, Mahesh; Ganesh, Krishna N. (Chimia, 2012)
Collagen is a major structural protein found in the connective tissues of higher organisms and mammals and its biomechanical properties are related to the high thermal stability of its triple helical structure. The primary structure of collagen is composed of the repeating tripeptide motif of Pro-Hyp-Gly, where Hyp is 4R-hydroxy proline. Cationic collagen mimetics consisting of [Pro(X)-Pro(Y)-Gly](6) where Pro(X) and Pro(Y) are 4(R/S)-amino/guanidine proline have been synthesized and shown to form triplexes more stable than the unmodified collagen peptide [Pro-Hyp-Gly](6). The origin of hyperstability is due to conformational pre-organization of proline pucker arising from the electronegativity of the cationic group. These cationic collagen peptides are shown to be effective cell penetrating and plasmid DNA transfecting agents. The results have potential for design of new collagen mimetics for biomaterial applications and efficient cell penetrating agents for drug delivery applications.
Keywords: 4-Aminoproline peptides; 4-Guanidino proline peptides; Cationic collagen mimetics; Cell penetrating peptides

4(R/S)-Guanidinylprolyl collagen peptides: on-resin synthesis, complexation with plasmid DNA, and the role of peptides in enhancement of transfection - Nanda, Manaswini; Ganesh, Krishna N. (Journal of Organic Chemistry, 2012)
Chimeric collagen peptides containing cationic 4(R/S)-guanidinylproline are synthesized by in situ amidinylation of 4(R/S)-aminoproline residues. These peptides uniquely enhance the transfection efficiency of GFP-encoded plasmid DNA (pRmHa3-GFP) into cells through efficient DNA condensation resulting from nonspecific electrostatic interactions of cationic guanidino groups and localize in subcytoplasmic organelles.

Alternative approach: a highly selective dual responding fluoride sensor having active methylene group as binding site - Das, Priyadip; Kesharwani, Manoj K.; Mandal, Amal K.; Suresh, Eringathodi; Ganguly, Bishwajit; Das, Amitava (Org Biomol Chem., 2012)
A newly designed phosphonium derivative (L) having active methylene functionality, shows unusual preference towards F− over all other anions. The binding process through C–H⋯F− hydrogen bond formation was probed by monitoring the changes in either electronic or luminescence spectra. Changes in both cases are significant enough to allow visual detection. The loss of molecular flexibility of L on forming L·F− effectively interrupts the non-radiative deactivation pathway and accounts for the observed switch on fluorescence response. The results of the time-resolved emission studies for L and L·F− using a time-correlated single photon counting technique further corroborate this presumption. The excellent preference of L towards F− is attributed to an efficient hydrogen bonding interaction between the strongly polarized methylene protons and F−, which delineates the subtle difference in the affinity among other competing anionic analytes like CN−, H2PO4−, CH3CO2−, etc. The relative affinities of various anions and the preferential binding of F− to reagent L are also rationalized using computational studies.

Amino functionalized oligo polyimides with enhanced storage stability - Dwivedi, Mayank; Rao, Locanindi Hari Sarvothama; Mohan, Srinivasulu Reddy Krishna; Dhanasekharan, Janakiraman; Rao, Bevara Madhusudana; Kumar, Sriperambudur Rajesh; Ponrathnam, Surendra; Rajan, Chelanattukizhakkemadath Raman; Tayal, Rajiv Kumar; Shadbar, Qureshi Mohammed; Chavan, Nayaku; Deokar, Sarika Babasaheb; et al. (WO2012090055A1, 2012)
The invention relates to an improved process for the preparation of amino functionalized oligomeric monomeric reactant type polyimides having higher stability. More particularly it relates to a process for the preparation of soluble imide prepolymers, used as matrix resins that can be rapidly cured with multi-functional moieties such as diepoxy, dicarboxyl, anhydride, diisocyanates to form crosslinked structures having enhanced thermal stability and mechanical strength.

Aminomethylene peptide nucleic acid (am-PNA): synthesis, regio-/stereospecific DNA binding, and differential cell uptake of (alpha/gamma,R/S)am-PNA analogues - Mitra, Roopa; Ganesh, Krishna N. (Journal of Organic Chemistry, 2012)
Inherently chiral, cationic am-PNAs having pendant aminomethylene groups at alpha(R/S) or gamma(S) sites on PNA backbone have been synthesized. The modified PNAs are shown to stabilize duplexes with complementary cDNA in a regio- and stereo-preferred manner with gamma(S)-am PNA superior to alpha(R/S)-am PNAs and alpha(R)-am PNA better than the alpha(S) isomer. The enhanced stabilization of am-PNA:DNA duplexes is accompanied by a greater discrimination of mismatched bases. This seems to be a combined result of both electrostatic interactions and conformational preorganization of backbone favoring the cDNA binding. The am-PNAs are demonstrated to effectively traverse the cell membrane, localize in the nucleus of He La cells, and exhibit low toxicity to cells.

Amylase gene expression patterns in Helicoverpa armigera upon feeding on a range of host plants - Kotkar, Hemlata M.; Bhide, Amey J.; Gupta, Vidya S.; Giri, Ashok P. (Gene, 2012)
Expression of two amylase genes (HaAmy1 and HaAmy2) was studied in Helicoverpa armigera (Hubner; Lepidoptera: Noctuidae) feeding on different host plants and during larval development. Alignment of HaAmy1 and HaAmy2 with other insect amylases shows similarities with known Lepidopteran amylase transcripts. H. armigera amylase gene expression is influenced by the availability of reducing sugars, sucrose and starch content of host plants and further correlates to the pool of reducing sugars in the gut and haemolymph of larvae. HaAmy1 and HaAmy2 during larval development on two host plants viz., maize (cereal) and marigold (ornamental) showed their relative difference. Results support the view that when host plants differ in their macronutrients, relationships of enzymes and substrates are flexible. The present work highlights the distribution of HaAmy1 and HaAmy2 (i) during various stages of insect development (second, fourth and sixth instar, pupa, adult and egg), (ii) in various tissues viz., head, haemolymph, fat body, integument and whole larval body of H. armigera feeding on artificial diet and (iii) in three gut regions of larvae fed on various diets. Complexity in expression of amylase genes suggests existence of mechanisms involved to detect nutrient balance required for avoiding fitness costs and focus their importance in insect nutrition. (C) 2012 Elsevier B.V. All rights reserved.
Keywords: Diets; Digestive amylase; Gene expression; Helicoverpa armigera; Nutrition

Analysis of AGE modified proteins and RAGE expression in HER2/neu negative invasive ductal carcinoma - Korwar, Arvind M.; Bhonsle, Hemangi S.; Chougale, Ashok D.; Kote, Sachin S.; Gawai, Kachru R.; Ghole, Vikram S.; Koppikar, Chaitanyananda B.; Kulkarni, Mahesh J. (Biochemical and Biophysical Research Communications, 2012)
Cancer is associated with increased glycolysis and carbonyl stress. In view of this, AGE modified proteins were identified from clinical breast cancer tissue using 2DE-immunoblot and mass-spectrometry. These proteins were identified to be serotransferrin, fibrinogen gamma chain, glycerol-3-phosphate dehydrogenase, lactate dehydrogenase, annexin II, prohibitin and peroxiredoxin 6, which have established role in cancer. Further, RAGE expression and its downstream signaling proteins NADPH oxidase and NF-kB were studied. Role of these AGE modified proteins and RAGE signaling in breast cancer is discussed. (C) 2012 Elsevier Inc. All rights reserved.
Keywords: advanced glycation end products; Breast cancer; RAGE

Analysis of miRNA regulation suggests an explanation for `unexpected' increase in target protein levels - Gokhale, Sucheta A.; Gadgil, Chetan J. (Molecular Biosystems, 2012)
MicroRNA (miRNA) has been mostly associated with decrease in target protein expression levels. Recently, `unexpected' observations of increase in target protein expression attributed to microRNA regulation have been reported. We formulate a comprehensive model for regulation by miRNA that includes both reversible mRNA-miRNA binding and selective return of RNA. We use this mathematical model incorporating multiple individual steps in the regulation process to study the simultaneous effects of these steps on the target protein level. We show that four dimensionless numbers obtained from 12 rate constants are sufficient to define the relative change in steady state target protein levels. We quantify the range of these numbers for which such pleiotropic increase in protein levels is possible, and interpret the experimental findings in the framework of our model such that the results are no longer unexpected. Finally, we show through stochastic simulation that the nature of the target protein distribution remains unchanged and the relative steady state noise levels are also completely defined by the values of these dimensionless numbers, irrespective of the individual reaction rate constants.

Antituberculosis agent diaportheone B: synthesis, absolute configuration assignment, and anti-TB activity of its analogues - Swaroop, Pandrangi Siva; Raut, Gajanan N.; Gonnade, Rajesh G.; Verma, Priyanka; Gokhale, Rajesh S.; Reddy, D. Srinivasa (Organic & Biomolecular Chemistry, 2012)
First synthesis of diaportheone B, an antituberculosis agent isolated from endophytic fungus Diaporthe sp. P133 is reported using two complementary routes, a one step and a three-step sequence. The absolute configuration of diaportheone B was determined by using X-ray crystal structure analysis of its dibromo derivative. In addition, we have prepared several close analogues of diaportheone B and determined their anti-TB potential using Alamar-blue assay (H(37)Rv).

Behavior of the transport and separation of lanthanum, yttrium and lutetium metal ions through a celluose fiber supported solid membrane - Gaikwad, Abaji G. (Macedonian Journal of Chemistry and Chemical Engineering, 2012)
A newly designed membrane cell was used to study the behavior of the transport and separation of lanthanum, yttrium and lutetium metal ions using a cellulose fiber supported solid membrane. The cellulose fiber membrane was prepared by the chemical modification of cellulose fiber using an esterification reaction with citric acid. Different experimental variables were investigated, such as time, membrane size, stirring of the source and receiving phases and the pH of the source phase. The use of different stripping agents in the receiving phase was explored, including nitric acid, hydrochloric acid, sodium nitrate, ammonium thiocyanate, D(2)EHPA, TBP, Aliquat-336, tartaric acid, EDTA and organic solvents. Pre-concentration of lanthanum, yttrium and lutetium metal ions from dilute solutions was carried out.
Keywords: binary mixture; cellulose fiber membrane; Citric acid; complexing reagent; Lanthanum; lutetium; metal ions; Separation; transport studies; yttrium

Bioanalytical method development and validation of levalbuterol a β2-adrenergic agonist by RP-HPLC method - Ghemud, A. S.; Santhakumari, B.; Pharne, A. B.; Jadhav, M. M.; Jain, K. S.; Kulkarni, Mahesh J. (International Journal of Pharmacy and Pharmaceutical Sciences, 2012)

Bioanalytical method development and validation of vildagliptin a novel dipeptidyl peptidase IV inhibitor by RP-HPLC method - Pharne, A. B.; Santhakumari, B.; Ghemud, A. S.; Jain, H. K.; Kulkarni, Mahesh J. (International Journal of Pharmacy and Pharmaceutical Sciences, 2012)
A simple, selective, rapid, precise and economical Reverse-Phase HPLC method has been developed and validated for quantitative determination of vildagliptin in plasma. Vildagliptin is a potent dipeptidyl peptidase IV inhibitor used for treatment of diabetes. Tolbutamide is used as an internal standard. The method was carried out with UV Spectrophotometric detection using a Perkin Elmer Series 200 HPLC system equipped with XBridge Shield C18 column (3.5 μm, 4.6x150mm) and a guard column of the same type, at a flow rate of 1.0mL/min. Detection was carried out at 210 nm. The mobile phase consisted of 50mM ammonium bicarbonate (pH 7.8) (solvent A) and acetonitrile (solvent B). The retention times of vildagliptin and tolbutamide were 11.2 min and 13.4 min respectively. The method was developed and tested for linearity range of 10μg/ml to 120μg/ml. The developed method was validated in terms of selectivity, accuracy, precision, linearity, and stability study. The proposed method uses less biological material and the method is MS compatible also. Method can be applicable for pharmacokinetic studies using HPLC or LC-MS.

Bistable dynamic coordination polymer showing reversible structural and functional transformations - Nagarkar, Sanjog S.; Das, Raja; Poddar, Pankaj; Ghosh, Sujit K. (Inorganic Chemistry, 2012)
A bistable dynamic coordination polymer [Ni(pca)(bdc)(0.5)(H2O)(2)] having a two-dimensional (2D) zigzag sheet structure is synthesized solvothermally. Topological analysis revealed that the frameworks have an hcb type of uninodal net. The compound exhibits guest specific reversible structural transformations accompanying reversible changes in physical properties driven by inherent flexibility and transformability.

Carbohydrate based total synthesis of xestodecalactone B and C: revision of the absolute configuration - Pal, Rita; Rahaman, Hasibur; Gurjar, Mukund K. (Current Organic Chemistry, 2012)
A convergent chiral pool approach for the total synthesis of xestodecalactones B and C was demonstrated in which intramolecular acylation reaction constituted the key step. Synthetic and spectroscopic studies reported herein, suggested that the previously assigned structures of xestodecalactone B and C be interchanged.
Keywords: Chiral pool; Hydroboration; Intramolecular acylation; Pinnick oxidation; Revision of absolute configuration; Xestodecalactone B and C

Carbohydrate-based synthesis of the C13-C22 fragment of amphidinolide X - Gurjar, Mukund K.; Yellol, Gorakh S.; Mohapatra, Debendra K. (European Journal of Organic Chemistry, 2012)
A facile carbohydrate-based route was developed for the synthesis of the tetrahydrofuran (C13C22) fragment of amphidinolide X. Starting from L-sorbose, the key reactions followed include the stereoselective synthesis of a quaternary center at C1, BartonMcCombie deoxygenation at C2, Mitsunobu inversion at C3, and chain elongation by a Wittig reaction at C5.
Keywords: Cytotoxicity; Macrolides; Mitsunobu inversion; Natural products; Wittig reactions

Carbon dioxide capture by metal organic frameworks - Saha, Subhadeep; Chandra, Suman; Garai, Bikash; Banerjee, Rahul (Indian Journal of Chemistry Section A-Inorganic Bio-Inorganic Physical Theoretical & Analytical Chemistry, 2012)
The design and synthesis of functionalized metal organic framework materials (MOFs) for reversible physisorption of CO2 is discussed. This strategy of CO2 adsorption in MOFs requires less energy for regeneration than materials relying on chemisorption. As a result the MOFs have received considerable attention as sorbent materials for strategic gases such as CO2 and H,. In this review, we have discussed different MOFs and hybrid materials containing MOFs which can adsorb CO2 at room temperature. In order to achieve high adsorption capacity, fast CO2 adsorption-desorption and low energy requirement for regeneration are necessary. Several avenues for increasing the CO2 adsorption capacity of such materials, for instance, introduction of open metal sites and the use of ligand molecules with specific functionalities (like -OH or -NH2) have been described. It has been observed that CO2 loading capacity of MOFs increases with functionalization. Herein, we have discussed how N-containing and fluorinated MOFs are designed to achieve higher CO2 loading than their non-functionalized counterparts. Nanocarbons (e.g. carbon nanotubes, carbon nanofibres, etc.) are porous materials and a blend of these porous materials with porous MOFs or porous carbon derived from MOFs may act as a better adsorbate than even the pure materials. Enhancement of CO2 loading by nanocarbon-MOF hybrid material is also discussed.
Keywords: Carbon dioxide adsorbents; Carbon dioxide capture; hybrid materials; Metal organic frameworks; Nanocarbons; Porous nanocarbons

Carbon dioxide reforming of methane over ruthenium substituted strontium titanate perovskite catalysts - Gurav, Hanmant R.; Bobade, Richa; Das, Vineetha Lakshmi; Chilukuri, Satyanarayana V. (Indian Journal of Chemistry Section A-Inorganic Bio-Inorganic Physical Theoretical & Analytical Chemistry, 2012)
Strontium titanate (SrTiO3) doped with varying amounts of ruthenium (7.9, 15.6 and 31 wt%) have been prepared by the citrate gel synthesis method. Structural and textural characterizations reveal that at lower concentrations, a major part of Ru is incorporated in the lattice of SiTiO3. The content of surface Ru (outside lattice) increases with increasing amounts of the doped Ru. The surface Ru reduced at lower temperatures compared to Ru incorporated into the lattice. The reduction of the lattice substituted Ru occurs only at temperatures above the collapse of the perovskite structure. The catalyst sample with 7.9 wt% of Ru shows good conversions in the dry reforming of methane with CO2. The conversion of CO2 is in excess compared to methane under the studied reaction conditions. As a result, H-2/CO ratio of the product gases which should have been equivalent to unity is lower than the stoichiometric value. This ratio is particularly low when lower reaction temperatures (873-973 K) were used. Similar was the case when high space velocities were used. Low methane conversion and reverse water gas shift reaction are the causes for the low H-2/CO ratios.
Keywords: Carbon dioxide reforming; Catalysts; Citrate gel method; Doped catalysts; Dry reforming; Methane reforming; Perovskites; Reverse water gas shift; Ruthenium doped catalysts; Strontium titanate; Syngas

Chemical deposition of CuInSe2 thin films by photoelectrochemical applications - Hankare, P. P.; Rathod, K. C.; Chate, P. A.; Garadkar, K. M.; Sathe, D. J.; Mulla, Imtiaz S. (Journal of Alloys and Compounds, 2012)
Copper indium diselenide films have been synthesized by chemical bath deposition method. The configuration of fabricated cell is n-CuInSe2|NaOH (1 M) + S (1 M) + Na2S (1 M)|C-(graphite). The photoelectrochemical cell characterization of the films is carried out by studying current-voltage characteristics in dark, capacitance-voltage in dark, barrier height measurements, power output, photoresponse and spectral response. The study shows that CuInSe2 thin films are n-type conductivity. The junction ideality factor is found to be 3.81. The flat band potential is found to be 0.763 V. The barrier height value is found to be 0.232 eV. The study of power output characteristic shows open circuit voltage, short circuit current, fill factor and efficiency are found to be 310 mV, 20 mu A, 42.12% and 0.82%, respectively. Photoresponse shows lighted ideality factor which is 2.92. Spectral response shows the maximum current observed at 650 nm. (C) 2011 Published by Elsevier B.V.
Keywords: Chemical bath deposition; Flat band potential; Photo response; Power output; Spectral response

Chiral crystals from an achiral molecule: 4,6-di-O-benzyl-1,3-O-benzylidene-2-O-(4-methoxybenzyl)-myo-5-inosose - Gurale, Bharat P.; Gonnade, Rajesh G.; Shashidhar, Mysore S. (Acta Crystallographica Section C-Crystal Structure Communications, 2012)
The title achiral compound, C35H34O7, crystallizes in the chiral monoclinic space group P21. The molecules are densely packed to form a helical assembly along the crystallographic twofold screw axis via CH...O and CH...p interactions. Interestingly, the unit-translated helical chains are loosely connected via a rather uncommon edge-to-edge PhH...HPh short contact (H...H = 2.33 angstrom).

Comparative genomics of the apicomplexan parasites toxoplasma gondii and neospora caninum: coccidia differing in host range and transmission strategy - Reid, Adam James; Vermont, Sarah J.; Cotton, James A.; Harris, David; Hill-Cawthorne, Grant A.; Koenen-Waisman, Stephanie; Latham, Sophia M.; Mourier, Tobias; Norton, Rebecca; Quail, Michael A.; Sanders, Mandy; Shanmugam, Dhanasekaran; et al. (Plos Pathogens, 2012)
Toxoplasma gondii is a zoonotic protozoan parasite which infects nearly one third of the human population and is found in an extraordinary range of vertebrate hosts. Its epidemiology depends heavily on horizontal transmission, especially between rodents and its definitive host, the cat. Neospora caninum is a recently discovered close relative of Toxoplasma, whose definitive host is the dog. Both species are tissue-dwelling Coccidia and members of the phylum Apicomplexa; they share many common features, but Neospora neither infects humans nor shares the same wide host range as Toxoplasma, rather it shows a striking preference for highly efficient vertical transmission in cattle. These species therefore provide a remarkable opportunity to investigate mechanisms of host restriction, transmission strategies, virulence and zoonotic potential. We sequenced the genome of N. caninum and transcriptomes of the invasive stage of both species, undertaking an extensive comparative genomics and transcriptomics analysis. We estimate that these organisms diverged from their common ancestor around 28 million years ago and find that both genomes and gene expression are remarkably conserved. However, in N. caninum we identified an unexpected expansion of surface antigen gene families and the divergence of secreted virulence factors, including rhoptry kinases. Specifically we show that the rhoptry kinase ROP18 is pseudogenised in N. caninum and that, as a possible consequence, Neospora is unable to phosphorylate host immunity-related GTPases, as Toxoplasma does. This defense strategy is thought to be key to virulence in Toxoplasma. We conclude that the ecological niches occupied by these species are influenced by a relatively small number of gene products which operate at the host-parasite interface and that the dominance of vertical transmission in N. caninum may be associated with the evolution of reduced virulence in this species.

Computational investigation of the role of the iridium dihydrogen pincer complex in the formation of the cyclic pentamer (NH2BH2)(5) - Ghatak, Kamalika; Vanka, Kumar (Computational and Theoretical Chemistry, 2012)
Computational studies with density functional theory (DFT) and MP2 have been done to investigate the interaction between the iridium dihydrogen pincer complex: (POCOP)IrH2 (where POCOP = eta(3)-1,3(OPt-Bu-2)(2)C6H3) and NH2BH2, the immediate product of ammonia borane (NH3BH3) dehydrogenation. A mechanism has been proposed for an oligomerisation process at the metal centre that involves competition between (i) insertion of an NH2BH2 molecule into the (NH2BH2)(n) chain and (ii) termination of the chain leading to the formation of the cyclic (NH2BH2)(n) oligomer. The calculated Delta G values show that the competition favours insertion over termination for the cases n = 1 to n = 4 but favours termination for n = 5. The computational studies therefore indicate that the cyclic pentamer (NH2BH2)(5) would be formed during NH3BH3 dehydrogenation by the (POCOP)IrH2 catalyst, agreeing with experimental findings. The mechanistic understanding gained has implications for the facile regeneration of ammonia borane. (C) 2012 Elsevier B.V. All rights reserved.
Keywords: Ammonia borane; Hydrogen storage; Iridium pincer ligand catalyst; Mechanistic studies; Oligomerisation cycle

Conformational transitions of the catalytic domain of heme-regulated eukaryotic initiation factor 2 alpha kinase, a key translational regulatory molecule - Sreejith, R. K.; Suresh, C. G.; Bhosale, Siddharth H.; Bhavnani, Varsha; Kumar, Avinash; Gaikwad, Sushama M.; Pal, Jayanta K. (Journal of Fluorescence, 2012)
In mammalian cells, the heme-regulated inhibitor (HRI) plays a critical role in the regulation of protein synthesis at the initiation step through phosphorylation of a-subunit of the eukaryotic initiation factor 2 (eIF2). In this study we have cloned and performed biophysical characterization of the kinase catalytic domain (KD) of rabbit HRI. The KD described here comprises kinase 1, the kinase insertion domain (KI) and kinase 2. We report here the existence of an active and stable monomer of HRI (KD). The HRI (KD) containing three tryptophan residues was examined for its conformational transitions occurring under various denaturing conditions using steady-state and time-resolved tryptophan fluorescence, circular dichroism (CD) and hydrophobic dye binding. The parameter A and phase diagram analysis revealed multi-state unfolding and existence of three stable intermediates during guanidine hydrochloride (Gdn-HCl) induced unfolding of HRI (KD). The protein treated with 6 M Gdn-HCl showed collisional and static mechanism of acrylamide quenching and the constants (K-sv=3.08 M-1 and K-s=5.62 M-1) were resolved using time resolved fluorescence titration. Based on pH, guanidine hydrochloride and temperature mediated transitions, HRI (KD) appears to exemplify a rigid molten globule-like intermediate with compact secondary structure, altered tertiary structure and exposed hydrophobic patches at pH 3.0. The results indicate the inherent structural stability of HRI (KD), a member of the class of stress response proteins.
Keywords: Circular dichroism (CD); eIF2 alpha kinase; Heme-regulated inhibitor; Molten globule; Steady-state and time-resolved fluorescence

Constrained variational approach for energy derivatives in Intermediate hamiltonian fock-space coupled-cluster theory - Ghosh, Aryya; Gupta, Jitendra; Pal, Sourav; Vaval, Nayana (Chemical Physics, 2012)
Fock-space multi-reference coupled cluster theory is an efficient method for electronic structure of nearly degenerate cases. However, it suffers from the intruder state problem for large model space. The intermediate Hamiltonian formulation eliminates intruder state problem and helps in the convergence of equations. In this paper we have implemented intermediate Hamiltonian approach in Fock-space coupled cluster method for the response properties. We test our method for the dipole moments of doublet radicals. We report dipole moments of CN, SF and NS radicals. (C) 2011 Elsevier B. V. All rights reserved.
Keywords: Constrained variational approach; Fock-space multi-reference coupled cluster; Intermediate Hamiltonian theory; Response approach

Controlled release of nutrients to mammalian cells cultured in shake flasks - Hegde, Swati; Pant, Tejal; Pradhan, Ketaki; Badiger, Manohar V.; Gadgil, Mugdha (Biotechnology Progress, 2012)
Though cell culture-based protein production processes are rarely carried out under batch mode of operation, cell line and initial process development operations are usually carried out in batch mode due to simplicity of operation in widely used scale down platforms like shake flasks. Nutrient feeding, if performed, is achieved by bolus addition of concentrated feed solution at different intervals, which leads to large transient increases in nutrient concentrations. One negative consequence is increased waste metabolite production. We have developed a hydrogel-based nutrient delivery system for continuous feeding of nutrients in scale down models like shake flasks without the need for manual feed additions or any additional infrastructure. Continuous delivery also enables maintaining nutrient concentrations at low levels, if desired. The authors demonstrate the use of these systems for continuous feeding of glucose and protein hydrolysate to a suspension Chinese Hamster Ovary (CHO) culture in a shake flask. Glucose feeding achieved using the glucose-loaded hydrogel resulted in a 23% higher integral viable cell density and an 89% lower lactate concentration at the end of the culture when compared with a bolus-feed of glucose. (c) 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2012

Controlled synthesis of O-glycopolypeptide polymers and their molecular recognition by lectins - Pati, Debasis; Shaikh, Ashif Y.; Das, Soumen; Nareddy, Pavan Kumar; Swamy, Musti J.; Hotha, Srinivas; Sen Gupta, Sayam (Biomacromolecules, 2012)
The facile synthesis of high molecular weight water-soluble O-glycopolypeptide polymers by the ring-opening polymerization of their corresponding N-carboxyanhydride (NCA) in very high yield (overall yield > 70%) is reported. The per-acetylated-O-glycosylated lysine-NCA monomers, synthesized using stable glycosyl donors and a commercially available protected amino acid in very high yield, was polymerized using commercially available amine initiators. The synthesized water-soluble glycopolypeptides were found to be alpha-helical in aqueous solution. However, we were able to control the secondary conformation of the glycopolypeptides (alpha-helix vs nonhelical structures) by polymerizing raceznic amino acid glyco NCAs. We have also investigated the binding of the glycopolypeptide poly(alpha-manno-O-lys) with the lectin Con-A using precipitation and hemagglutination assays as well as by isothermal titration calorimetry (ITC). The ITC results clearly show that the binding process is enthalpy driven for both alpha-helical and nonhelical structures, with negative entropic contribution. Binding stoichiometry for the glycopolypeptide poly(alpha-manno-O-lys) having a nonhelical structure was slightly higher as compared to the corresponding polypeptide which adopted an alpha-helical structure.

Conversion of cellulose to polyols over promoted nickel catalysts - Shrotri, Abhijit; Tanksale, Akshat; Beltramini, Jorge Norberto; Gurav, Hanmant; Chilukuri, Satyanarayana V. (Catalysis Science & Technology, 2012)
Sorbitol is one of the key platform chemicals that can be applied to several industrial applications, including bio-fuels and hydrogen production. Presently there is no commercial heterogeneous catalytic process to produce sorbitol from cellulose due to the low yield and high cost of noble metals required for the conversion. In this paper we describe an aqueous phase hydrolysis-hydrogenation process to convert cellulose to sorbitol using a cheap Ni based catalyst. Monometallic Ni catalysts showed little activity for the reaction, but with the addition of a small amount of Pt to the Ni catalyst (Ni : Pt = 22 : 1 atom ratio), the activity was greatly enhanced. Results showed that the bimetallic Ni-Pt catalysts supported on mesoporous alumina gave a hexitol (sorbitol + mannitol) yield of 32.4% compared to only 5% with a Ni catalyst. Moreover, Ni-Pt supported on a mesoporous beta zeolite support provided even higher yield of 36.6%. These results were obtained after only 6 hours of run at 200 degrees C and 50 bar H-2 pressure (at room temperature). The presence of a small amount of Pt promotes the protonation of water and hydrogen molecules, which spill over to Ni sites creating in situ acid sites to catalyse hydrolysis of cellulose.

Crystal structure of (2S, 4R)-2-benzyl 1-tert-butyl 4-(tosyloxy)pyrrolidine-1,2-dicarboxylate, C24H29NO7S - Ghosh, Munmun; Mallick, Arijit; Diaz, David Diaz (Zeitschrift Fur Kristallographie-New Crystal Structures, 2012)
{C24H29NO7S, triclinic, P1 (no. 1)

Cu-II-exchanged montmorillonite K10 clay-catalyzed direct carboxylation of terminal alkynes with carbon dioxide - Aher, Ravindra D.; Gade, Madhuri H.; Reddy, R. Santhosh; Sudalai, Arumugam (Indian Journal of Chemistry Section A-Inorganic Bio-Inorganic Physical Theoretical & Analytical Chemistry, 2012)
A new, simple and straight-forward protocol for direct carboxylation of terminal alkynes has been developed using Cu-II-montmorillonite K10 clay as a heterogeneous catalyst and CO2 as the C1 carbon feedstock. Also coupling of terminal alkynes with CO2 (1 atm) in the presence of alkyl halides has been achieved under the same reaction conditions, thereby providing access to a variety of functionalized alkyl-2-alkynoates in high yields.
Keywords: Alkyl esters; Alkyne C-H activation; Carbon dioxide activation; Carboxylation; Catalysts; Montmorillonite clays

CVD synthesis of highly graphitized single-walled carbon nanotubes using nitrogen-pretreated Fe-Mo/MgO catalyst - Patil, Gaurav; Sarode, Chetan; Patil, Rahul; Gokhale, Suresh (Chemistry Letters, 2012)
Single-walled carbon nanotubes (SWNTs) with highly graphitized structure were synthesized by thermal chemical vapor deposition using an improved nitrogen-pretreated Fe-Mo/MgO catalyst. The effects of nitrogen pretreatment of Fe-Mo/MgO on the structure and properties of SWNTs were studied by TEM, Raman spectroscopy, and TGA. The investigations revealed that the nitrogen pretreatment of the catalyst promoted the growth of SWNTs. It also enhanced the structural features and thermal properties of SWNTs.

Deposition-precipitation versus anionic-exchange Au/Al2O3 catalysts: a comparative investigation towards the selective reduction of NOx - Nguyen, D. L.; Shubhangi B. Umbarkar; Dongare, Mohan K.; Lancelot, Christine; Girardon, J. S.; Dujardin, Christophe; Granger, P. (Catalysis Communications, 2012)
Catalytic properties of supported gold catalysts on gamma-Al2O3 prepared by a conventional deposition-precipitation method were compared with those obtained by anionic-exchange for the reduction of NOx by hydrocarbon under lean conditions that simulate Diesel engine exhaust gas. Interestingly, a catalytic activity enhancement is observed after thermal ageing under reactive conditions at 500 degrees C on anionic-exchanged samples which make them suitable for practical developments. On the other hand, the reverse trend is observed on the solids prepared by deposition-precipitation which deactivate at low temperature. Such changes in catalytic properties have been tentatively explained on the basis of textural and structural modifications taking place during thermal ageing under wet atmosphere. (C) 2012 Elsevier B.V. All rights reserved.
Keywords: Anionic-exchange; Au catalyst; Deposition-precipitation; NOx abatement; Selective catalytic reduction

Development of genomic simple sequence repeat markers for linseed using next-generation sequencing technology - Kale, Sandip M.; Pardeshi, Varsha C.; Kadoo, Narendra Y.; Ghorpade, Prakash B.; Jana, Murari M.; Gupta, Vidya S. (Molecular Breeding, 2012)
Linseed (Linum usitatissimum L.) is regarded as a cash crop of tomorrow because of the presence of nutraceutically important alpha-linolenic acid (ALA) and lignan. However, only limited breeding progress has been made in this crop, mainly due to the lack of sufficient genetic and genomic resources. Among these, simple sequence repeats (SSR) are useful DNA markers for diversity analysis, genetic mapping and tagging traits because of their co-dominant and highly polymorphic nature. In order to develop SSR markers for linseed, we used three microsatellite isolation methods, viz., PCR Isolation of Microsatellite Arrays (PIMA), 5'-anchored PCR method, and Fast Isolation by AFLP of Sequences COntaining repeats (FIASCO). The amplified products from these methods were pooled and sequenced using the 454 GS-FLX platform. A total of 36,332 reads were obtained, which assembled into 2,183 contigs and 2,509 singlets. The contigs and the singlets contained 1,842 microsatellite motifs, with dinucleotide motifs as the most abundant repeat type (54%) followed by trinucleotide motifs (44%). Based on this, 290 SSR markers were designed, 52 of which were evaluated using a panel of 27 diverse linseed genotypes. Among the three enrichment methods, the 5'-anchored PCR method was most efficient for isolation of microsatellites, while FIASCO was most efficient for developing SSR markers. We show the utility of next-generation sequencing technology for efficiently discovering a large number of microsatellite markers in non-model plants.
Keywords: Flax; Microsatellite isolation; Next-generation sequencing; SSR

Developmental and digestive flexibilities in the midgut of a polyphagous pest, the cotton bollworm, helicoverpa armigera - Sarate, P. J.; Tamhane, V. A.; Kotkar, H. M.; Ratnakaran, N.; Susan, N.; Gupta, Vidya S.; Giri, Ashok P. (Journal of Insect Science, 2012)
Developmental patterns and survival of the cotton bollworm, Helicoverpa armigera Hubner (Lepidoptera: Noctuidae), a polyphagous insect pest, have been studied with reference to the effect of diet on major gut digestive enzymes (amylases, proteases, and lipases). Significant correlations between nutritional quality of the diet and larval and pupal mass were observed when H. armigera larvae were fed on various host plants viz. legumes (chickpea and pigeonpea), vegetables (tomato and okra), flowers (rose and marigold), and cereals (sorghum and maize). Larvae fed on diets rich in proteins and/or carbohydrates (pigeonpea, chickpea, maize, and sorghum) showed higher larval mass and developed more rapidly than larvae fed on diets with low protein and carbohydrate content (rose, marigold, okra, and tomato). Low calorific value diets like rose and marigold resulted in higher mortality (25-35%) of H. armigera. Even with highly varying development efficiency and larval/pupal survival rates, H. armigera populations feeding on different diets completed their life cycles. Digestive enzymes of H. armigera displayed variable expression levels and were found to be regulated on the basis of macromolecular composition of the diet. Post-ingestive adaptations operating at the gut level, in the form of controlled release of digestive enzymes, might be a key factor contributing to the physiological plasticity in H. armigera.
Keywords: amylases; larval performance; Lipases; Proteases

Dimethyl [(2R,3R,5S)-5-phenylmorpholine-2,3-diyl]diacetate as a designer substrate in the syntheses of important heterocyclic scaffolds - Pandey, Ganesh; Gaikwad, Amrut L.; Gadre, Smita R. (Asian Journal of Organic Chemistry, 2012)
Designed scaffold dimethyl [(2R,3R,5S)-5-phenylmorpholine-2,3-diyl]diacetate was synthesized in optically pure form by photoinduced one-electron reductive beta-activation of an alpha,beta-unsaturated carbonyl moiety for stereoselective C-C bond formation. Use of the morpholine derivative as a ``chemical multitalent'' is demonstrated by its easy transformation to valuable heterocyclic building blocks such as methyl [(2R,3S)-3-hydroxy-5-oxopyrrolidin-2-yl]acetate, methyl [(2R,3S)-3-amino-5-oxotetrahydrofuran-2-yl]acetate, (3R,4S)-4-aminohexane-1,3,6-triol, and 2-[(2R,3S)-3-aminotetrahydrofuran-2-yl]ethanol.
Keywords: Amino alcohols; butyrolactams; butyrolactones; morpholines; photoinduced electron transfer reactions

Dynamic proteome in enigmatic preeclampsia: an account of molecular mechanisms and biomarker discovery - Mary, Sheon; Patil, Gouri V.; Kulkarni, Asmita V.; Kulkarni, Mahesh J.; Joshi, Sadhana R.; Mehendale, Savita S.; Giri, Ashok P. (Proteomics Clinical Applications, 2012)
The coevolution of genomics and proteomics has led to advancements in the field of diagnosis and molecular mechanisms of disease. Proteomics is now stepping into the field of obstetrics, where early diagnosis of pregnancy complication such as preeclampsia (PE) is imperative. PE is a multifactorial disease characterized by hypertension with proteinuria, which is a leading cause of maternal and neonatal morbidity and mortality occurring in 5-7% of pregnancies worldwide. This review discusses the probable molecular mechanisms that lead to PE and summarizes the proteomics research carried out in understanding the pathogenicity of PE, and for identifying the candidate biomarker for diagnosis of the disease.
Keywords: Hypertension; Oxidative stress; Pregnancy complication; Proteinuria

Effect of addition of `carrier' DNA during transient protein expression in suspension CHO culture - Pradhan, Ketaki; Gadgil, Mugdha (Cytotechnology, 2012)
Transient protein expression using polyethyleneimine as a transfection agent is useful for the rapid production of small amounts of recombinant proteins. It is known that an increase in extracellular DNA concentration during transfection can lead to a nonlinear increase in intracellular DNA concentration. We present an approach that hypothesizes that this nonlinearity can be used to decrease the amount of plasmid required for productive transfections. Through addition of non coding `carrier' DNA to increase total DNA concentration during transfection, we report a statistically significant increase in protein (IgG) expression per unit plasmid used for transfection. This approach could be useful to increase protein yields for large scale transfections under conditions where plasmid availability is limited.
Keywords: Carrier DNA; Cell age; DNA: polyethyleneimine particle size; Medium equilibration with CO2; pH excursion; Salmon sperm DNA; Transient protein expression

Effects of arsenite stress on growth and proteome of Klebsiella pneumoniae - Daware, Vandana; Kesavan, Suresh K.; Patil, Rajendra; Natu, Arvind; Kumar, Ameeta; Kulkarni, Mahesh J.; Gade, Wasudeo N. (Journal of Biotechnology, 2012)
In the present study an arsenite, As(III), tolerating bacterium, MR4, was isolated from Mulla River Pune, India, capable of reducing arsenate to arsenite and identified as Klebsiella pneumoniae (HQ857583). Comparative proteomic analysis using two-dimensional gel electrophoresis (2-DGE) and matrix assisted laser desorption ionization-time of flight-time of flight (MALDI-TOF/ TOF) was used to monitor the proteins undergoing changes in expression levels under 2.5 mM As(III) stress. The 2-DGE proteome map has shown that 60 proteins were differentially expressed under As(III) stress, of which 39 proteins were successfully identified with a MASCOT score greater than 70 (p < 0.05). Among the identified proteins, membrane transport/ binding proteins, porins, and amino acid metabolism enzymes were down-regulated while stress responsive proteins and antioxidant enzymes were up-regulated. Proteins involved in carbohydrate metabolism, particularly those in pentose phosphate pathway were also up-regulated while those involved in pyruvate metabolism were down-regulated. However, proteins involved in glycolysis and tricarboxylic acid cycle showed a mixed regulation response. These findings provide new insights into the probable mechanisms by which K. pneumoniae (HQ857583) could be adapting to As(III) stress. (C) 2012 Elsevier B.V. All rights reserved.
Keywords: (2-DGE); Arsenite stress; Klebsiella pneumoniae; MALDI-TOF-TOF; Two dimensional gel electrophoresis

Effects of grain morphology, microstructure and dispersed metal cocatalyst on the photoreduction of water over impurity-doped LaInO3 - Dhanasekaran, P.; Gupta, N. M. (Materials Research Bulletin, 2012)
The single phase lanthanum indates doped with Ga (for La) and N (for O), i.e. La1-xGaxInO3 (0 <= x <= 0.2) and LaInO1-yNy (y similar to 0.6), exhibit significant activity for photoreduction of water; the yield of H-2 produced depending on dopant, excitation source, and addition of a sacrificial reagent. The two-step H-2 evolution observed for this reaction corresponds with the two distinct absorbance regimes displayed by these materials, one in UV-region due to bandgap excitation and the other in visible region arising from the transitions involving sub-bandgap donor or acceptor energy states. The photocatalytic activity of these d(10) metal oxides increases on coating with a metal/metal oxide co-catalyst, gold exhibiting superior activity to Pt and NiO, irrespective of excitation source and sample composition. The preparation-controlled particle morphology, doping-induced lattice imperfections, and metal/semiconductor hetero-junctions are envisaged to play a key role in the absorption characteristics and photocatalytic water reduction activity of metal/LaInO3 nanocomposites. (C) 2012 Elsevier Ltd. All rights reserved.
Keywords: Catalytic properties; Chemical synthesis; Electron microscopy; Interfaces; Semiconductors

Efficient lipase purification using reverse micellar extraction - Gaikaiwari, Raghavendra P.; Wagh, Shilpa A.; Kulkarni, Bhaskar D. (Bioresource Technology, 2012)
Reverse micellar extraction (RME) of enzyme provides an attractive option for conventional method with the potential to achieve purification and concentration in a single step with high yield. This study presents a methodology for optimization of RME with Pseudomonas lipase as model system. Fold-purification, percent recovery and extraction time were the objective functions while the type and concentration of surfactant, contact time, pH, ionic strength, and the ratio of organic to aqueous phase were the decision variables. Under optimized conditions, the AOT (Aerosol OT (bis 2-ethylhexyl) sodium sulfosuccinate)-isooctane system gave a 15-fold purification, 80% recovery and 2.5-fold concentration of the Pseudomonas lipase with process time of 45 min. (C) 2011 Elsevier Ltd. All rights reserved.
Keywords: (Hexadicetyltrimethylammoniumbromide); AOT; CTAB; Lipase; RME

Efficient total synthesis of calothrixin B - Bhosale, Shrikar M.; Gawade, Rupesh L.; Puranik, Vedavati G.; Kusurkar, Radhika S. (Tetrahedron Letters, 2012)
An efficient synthesis of calothrixin B (2) is demonstrated starting from 9H-carbazol-4-ol, having two one-pot reaction sequences as key steps. As a novel observation, DMF-methanol was shown to be a hydride donor for reduction of aldehyde to alcohol. Unexpectedly, nucleophilic substitution of benzyloxy by methoxy group was observed. (C) 2012 Elsevier Ltd. All rights reserved.
Keywords: Calothrixin B; CAN; DMF-methanol; Hydride donor

Enantioselective synthesis of HIV protease inhibitor amprenavir via Co-catalyzed HKR of 2-(1-azido-2-phenylethyl)oxirane - Gadakh, Sunita K.; Reddy, R. Santhosh; Sudalai, Arumugam (Tetrahedron-Asymmetry, 2012)
A short and efficient enantioselective synthesis of the HIV protease inhibitor amprenavir 1 (99% ee) as well as a formal synthesis of saquinavir 3 have been achieved in high enantiomeric purity starting from commercially available materials. Our strategy mainly comprises a Co-catalyzed two-stereocentred hydrolytic kinetic resolution (HKR) of racemic 2-(1-azido-2-phenylethyl)oxirane as the chirality inducing step. Also presented is a concise synthesis of (S)-3-hydroxytetrahydrofuran 4, the key structural feature, in high enantiomeric purity (98% ee). (c) 2012 Elsevier Ltd. All rights reserved.

Encapsulation of enzyme in large mesoporous material with small mesoporous windows - Malvi, Bharmana; Sen Gupta, Sayam (Chemical Communications, 2012)
Trypsin has been encapsulated in the mesopores of a hierarchical mesoporous silica material synthesized via Cu(I) catalyzed azide-alkyne click reaction between azide functionalized large spherical SBA-15 particles and alkyne functionalized mesoporous silica nanoparticles (MSNs). Encapsulated trypsin functions as an efficient biocatalyst and can be recycled several times.

Enhanced permeation, leaf retention, and plant protease inhibitor activity with bicontinuous microemulsions - Tamhane, Vaijayanti A.; Dhaware, Deepika G.; Khandelwal, Neha; Giri, Ashok P.; Panchagnula, Venkateswarlu (Journal of Colloid and Interface Science, 2012)
Bicontinuous microemulsions (BCMEs) have excellent solubulizing properties along with low interfacial tension and aqueous content that can be controlled. In this work, water soluble plant protease inhibitor (PI), well characterized for its activity against insect pests, was incorporated into a BCME system and explored for permeation on hydrophobic leaf surfaces and protease inhibition activity. The bicontinuous nature of the microemulsion containing water:2-propanol:1-butanol (55:35:10 w/w) was characterized using conductivity and self-diffusion coefficient measurements. The PI was soluble in the water-rich bicontinuous domains, stable in the microemulsions, and protease inhibition activity was retained for a prolonged duration. The microemulsions ensured greater wettability and a wider spread of the PI on hydrophobic leaf surfaces as revealed by contact angle measurements. Significantly, trypsin inhibition activity assays of the PI recovered from the leaves after delivery from the microemulsion indicated a significant increase in the PI retention on the leaf. This BCME enabled greater leaf permeation and retention of the PI can be attributed to a temporary disruption of the waxy leaf surface followed by self-repair without causing any long term damage to the plant. (C) 2012 Elsevier Inc. All rights reserved.
Keywords: Bicontinuous microemulsion; Biopesticide; Microemulsion pesticide; protease inhibitor; Protein encapsulation; Protein permeation

Enhanced photocatalytic activity of multi-doped TiO2 for the degradation of methyl orange - Charanpahari, A.; Umare, S. S.; Gokhale, S. P.; Sudarsan, V.; Sreedhar, B.; Sasikala, R. (Applied Catalysis A-General, 2012)
We report the synergistic effect of dopants like Gd, N and Sin enhancing the photocatalytic activity of TiO2. Nanosized TiO2 doped at both cationic and anionic sites by Gd, N and S exhibited increased photocatalytic activity compared to TiO2 doped with either Gd or N and S. All the doped TiO2 existed as anatase phase and no separate phase due to Gd2O3 was seen up to a Gd concentration of 2%. The particle size as seen from the transmission electron micrograph was similar to 25 nm. The optical absorption property of TiO2 was improved by doping and redshift of the absorption edge is seen for all doped samples compared to pristine TiO2. The red shift of the absorption edge was the highest for the multiple ion-doped sample. Presence of bonded N and S in TiO2 was detected by X-ray photoelectron spectroscopy. Fluorescence lifetime studies indicated an enhanced lifetime for the charge carriers in the doped system compared to pristine TiO2. Photocatalytic activity study showed that the multi-doped sample has the highest activity for the degradation of methyl orange compared to Gd-TiO2, NS-TiO2 and pristine TiO2. The enhanced photocatalytic activity of the multi-doped TiO2 is attributed to factors such as improved optical absorption property and improved lifetime of the charge carriers. (C) 2012 Elsevier B.V. All rights reserved.
Keywords: Fluorescence lifetime; Gd N S doped TiO2; Methyl orange; Photocatalyst; Photodegradation

Enhancing the hydrogen storage capacity of Pd-functionalized multi-walled carbon nanotubes - Singh, Priyanka; Kulkarni, Mukta V.; Gokhale, Suresh P.; Chikkali, Samir H.; Kulkarni, Chandrashekhar V. (Applied Surface Science, 2012)
We demonstrate that the hydrogen storage capacity of multi-walled carbon nanotubes can be enhanced by polyvinylpyrrolidone functionalization. The polyvinylpyrrolidone acts as a stabilizing agent for Pd-nanoparticles, reduces their size and facilitates their uniform and enhanced loading onto multi-walled carbon nanotubes. According to sorption studies, the polyvinylpyrrolidone capping and consequent nanostructural modification enables 2.3 times more hydrogen adsorption than mere Pd-functionalization of multi-walled carbon nanotubes. Corresponding morphological changes before and after polyvinylpyrrolidone capping, characterized using Raman Spectroscopy, X-ray diffraction, TEM and thermal analysis techniques, are also presented. The results contribute towards increasing the efficiency of hydrogen based sustainable energy sources. (C) 2011 Elsevier B.V. All rights reserved.
Keywords: Hydrogen based energy sources; Hydrogen storage capacity; Multiwalled carbon nanotubes; Pd functionalization; PVP capping

Environmental pollution reduction in cement industry for cocombustion of waste tyre and coal as a fuel - Patil, R. K.; Garnaik, Baijayantimala; Khond, M. P.; Nawale, L. G. (International Journal of Modern Engineering Research, 2012)
In recent years, there are several problems encountered in waste management system particularly waste tyre as well as coals. The energy generation on incineration provides large amount of polycyclic aromatic hydrocarbon (PAH) emissions which is the cause of major environmental threat. Therefore, the combustion of coal and tyre were carried out in cement industry in order to generate heat energy at 1300oC and the only remaining residue (steel powder) to enhance the strength of the cement. At the outset, the particle size of coal and tyre was cut into 63-75 and 180-212 µm respectively. Combustion experiments were conducted using Nelson reactor under controlled conditions in presence of air and also in presence of nitrogen gas (INOX) atmosphere. The temperature range was varied from 300-13000C and several fuel mass loading in the furnace, expressed in terms of bulk equivalence ratios in the range of 0.7-2.4. At fixed bulk equivalence ratios, as the furnace gas (Air) temperature increased the polycyclic aromatic hydrocarbon yields from both fuels decreased drastically, while the CO2 yields increased. At the highest temperature around 13000C, the effluent of combustion of both (coal and tyre) fuels was practically devoid of polycyclic aromatic hydrocarbon (PAH) (at a detection limit of 0.3 µg of a PAH component/g of fuel burnt). In order to understand the rate of thermal effect and morphology of co combustion material (coal and tyre), the preliminary results are very essential to explore. Therefore, the thermo gravimetric analysis (TGA) and environmental scanning electron microscopy (ESEM) were carried out and results of coal and tyre mixture at various temperature conditions will be highlighted.

Environmentally benign synthesis of beta-hydroxy sulfides using cyclic carbonates catalyzed by large-pore zeolites - Upare, Pravin P.; Kinage, Anil K.; Shingote, Savita K.; Gupte, Sunil P. (Green Chemistry Letters and Reviews, 2012)
An efficient one-pot synthesis of beta-hydroxy sulfides from thiophenol and cyclic carbonates catalyzed by large-pore zeolites has been reported. Reaction of thiophenol with ethylene carbonate in the presence of the Na-X zeolite catalyst gave the highest yield of 2-(phenylthio)ethanol (100%), while reaction with propylene carbonate a highest yield of regioselective product 1-(phenylthio)propan-2-ol was obtained (97%). Enantiomerically pure 1,2-propylene carbonate gave highly regioselective and stereospecific phenylthiopropanol, demonstrating that original chirality of propylene carbonate is retained. A plausible mechanism has been proposed for zeolite-catalyzed transformation involving a chemoselective nucleophilic attack of thiophenoloxide ion onto the less-substituted carbon of cyclic carbonate. The Na-X zeolite catalyst is recyclable and provides advantages of green chemistry approach to the synthesis of beta-hydroxy sulfides without the use of any solvent.
Keywords: beta-hydroxy sulfide; ethylene carbonate; propylene carbonate; thiophenol; zeolite

Epitaxial magnetic oxide nanocrystals via phase decomposition of bismuth perovskite precursors - Bogle, Kashinath A.; Cheung, Jeffrey; Chen, Yong-Lun; Liao, Sheng-Chieh; Lai, Chih-Hung; Chu, Ying-Hao; Gregg, John M.; Ogale, Satishchandra B.; Valanoor, Nagarajan (Advanced Functional Materials, 2012)
The phase instability of bismuth perovskite (BiMO3), where M is a ferromagnetic cation, is exploited to create self-assembled magnetic oxide nanocrystal arrays on oxide supports. Conditions during pulsed laser deposition are tuned so as to induce complete breakdown of the perovskite precursor into bismuth oxide (Bi2O3) and metal oxide (M-Ox) pockets. Subsequent cooling in vacuum volatizes the Bi2O3 leaving behind an array of monodisperse nanocrystals. In situ reflective high energy electron diffraction beam is exploited to monitor the synthesis in real-time. Analysis of the patterns confirms the phase separation and volatization process. Successful synthesis of M-Ox, where M = Mn, Fe, Co, and Cr, is shown using this template-free facile approach. Detailed magnetic characterization of nanocrystals is carried out to reveal the functionalities such as magnetic anisotropy as well as larger than bulk moments, as expected in these oxide nanostructures.
Keywords: Bi2O3 evaporation; bismuth perovskites; epitaxial nanostructures; magnetic oxides; phase separation

Equation-of-motion coupled-cluster method for the study of shape resonance - Ghosh, Aryya; Vaval, Nayana; Pal, Sourav (Journal of Chemical Physics, 2012)
The equation-of-motion coupled-cluster method (EOM-CC) is applied for the first time to calculate the energy and width of a shape resonance in an electron-molecule scattering. The procedure is based on inclusion of complex absorbing potential with EOM-CC theory. We have applied this method to investigate the shape resonance in e(-)N(2), e(-)CO, and e(-)C(2)H(2). (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4729464]

Ethyl oligo-silicates with strong acid heterogeneous polymeric catalysts - Bevara, Madhusudana Rao; Bhongale, Sunil Sitaram; Bhosle, Sonali Madhavrao; Chavan, Nayaku; Chelanattukizhakkemadath, Raman Rajan; Deokar, Sarika Babasaheb; Dhoble, Deepa Arun; Dwivedi, Mayank; Ghorpade, Ravindra V.; Harikrishna, Reghunathan; Dhanasekharan, Janakiraman; John, Aruldoss; et al. (WO2012056290 A1, 2012)
The present invention provides a process for the synthesis of ethyl silicate with varying silica concentration, by hydrolysing ethyl silicate in varying water concentration in the presence of sulfonated catalysts having a styrene-divinyl benzene backbone. The present invention further relates to the preparation of beaded crosslinked polymers containing sulfonic acid moieties having an interconnected pore structure and surface area up to 400 m2 /g.

Evidence of cationic Pt active for water-gas shift reaction: Pt-doped BaCeO3 perovskite - Rajesh, Thattarathody; Rajarajan, Anakot K.; Gopinath, Chinnakonda S.; Devi, R. Nandini (Journal of Physical Chemistry C, 2012)
Precious metal incorporated into stable lattices like perovskites can be envisaged as an alternative catalysts to address deactivation problems. Here we report the barium cerate perovskite doped with varying amounts of Pt as catalysts for the water-gas shift reaction whereby ionic Pt is evidenced to be active. It is found that maximum CO conversion occurs above 325 degrees C and increases more than 2-fold after the first cycle. XPS analysis shows that after the first cycle, more ionic Pt species are present on the surface of the catalyst. X-ray and neutron diffraction studies also indicate the presence of oxygen vacancies that increases with increasing Pt substitution.

Exploring the potential of doped zero-dimensional cages for proton transfer in fuel cells: a computational study - Mane, Manoj V.; Venkatnathan, Arun; Ghatak, Kamalika; Vanka, Kumar (Journal of Physical Chemistry B, 2012)
Calculations with density functional theory (DFT) and MP2 have been done to investigate the potential of recently synthesized durable zero-dimensional (OD) nitrogen-based cage structures to perform as efficient proton-exchange membranes (PEMs) in fuel cells. Our calculations suggest that the hydrogenated 0-D cages, in combination with hydrogen-bonding 1,2,3- and 1,2,4-triazole molecules, would perform as highly efficient PEMs. The results are important in the context of the need for efficient PEMs for fuel cells, especially at higher temperatures (greater than 120 degrees C) where conventional water-based PEMs such as Nafion have been found to be ineffective.

Extraction and purification of tannase by reverse micelle system - Gaikaiwari, Raghavendra P.; Wagh, Shilpa A.; Kulkarni, Bhaskar D. (Separation and Purification Technology, 2012)
Tannin acyl hydrolase commonly called as tannase (EC 3.1.1.20) is a commercially important enzyme. Partially purified and concentrated tannase is required for commercial applications. Typical objectives of purification process comprise high fold-purification, recovery and concentration. These objectives may be potentially conflicting. Conventional methods of purification require multiple steps which are time consuming and may cause higher loss. Reverse micellar extraction (RME) using ionic surfactants provides an attractive option for concentration and purification of tannase which is a highly hydrophilic glycoprotein. This study presents an optimized methodology for RME and purification of Aspergillus allahabadi intracellular tannase. Fold-purification, percent recovery and extraction time were the objective while the type and concentration of surfactant, contact time, pH, ionic strength, and the ratio of organic to aqueous phase were the decision variables. Some of these parameters were also studied for their effect on back-extraction. Among the surfactants tested, CTAB-isooctane system was found to be suitable. Under optimized conditions, 12.7-fold purification, 81.2% recovery and 3-fold concentration of tannase with a process time of 45 min was obtained. Conventional purification methods provided a higher fold-purification albeit at a much lower enzyme recovery. Further, the conventional method requires a process time of several hours. (c) 2012 Elsevier B.V. All rights reserved.
Keywords: CTAB; Reverse micellar extraction; Tannase

Factors affecting the production of H-2 by water splitting over a novel visible-light-driven photocatalyst GaFeO3 - Dhanasekaran, P.; Gupta, N. M. (International Journal of Hydrogen Energy, 2012)
A d(10) photocatalyst, GaFeO3 having a band gap of similar to 2.7 eV, exhibits significant activity for the overall splitting of water under visible light (>395 nm) irradiation, in the absence of sacrificial reagent or a noble metal co-catalyst. The doping of an anion led to considerable enhancement in activity, the S-doped catalysts displaying better activity compared to the samples containing nitrogen. Even though the H-2/O-2 yields were affected by preparation-dependent grain morphology, no direct relationship was observed between the photoactivity of a sample and its specific surface area. The techniques of HRTEM, SEM, XPS, Laser Raman, UV-visible and photoluminescence spectroscopy have enabled to demonstrate that, besides the grain morphology, certain lattice imperfections and microstructure may also play a crucial role in water splitting activity of a photocatalyst. The factors responsible for catalyst deactivation are examined. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Keywords: GaFeO3; hydrogen production; Microstructure; Photocatalyst; water splitting

First-principle protocol for calculating ionization energies and redox potentials of solvatedmolecules and ions: theory and application to aqueous phenol and phenolate - Ghosh, Debashree; Roy, Anirban; Seidel, Robert; Winter, Bernd; Bradforth, Stephen; Krylov, Anna I. (Journal of Physical Chemistry B, 2012)
The effect of hydration on the lowest vertical ionization energy (VIE) of phenol and phenolate solvated in bulk water was characterized using the equation-of-motion ionization potential coupled-cluster (EOM-IP-CCSD) and effective fragment potential (EFP) methods (referred to as EOM/EFP) and determined experimentally by valence photoemission measurements using microjets and synchrotron radiation. The computed solvent-induced shifts in VIEs (Delta VIEs) are 0.66 and +5.72 eV for phenol and phenolate, respectively. Our best estimates of the absolute values of VIEs (7.9 and 7.7 eV for phenol and phenolate) agree reasonably well with the respective experimental values (7.8 +/- 0.1 and 7.1 +/- 0.1 eV). The EOM/EFP scheme was benchmarked against full EOM-IP-CCSD using microsolvated phenol and phenolate clusters. A protocol for calculating redox potentials with EOM/EFP was developed based on linear response approximation (LRA) of free energy determination. The oxidation potentials of phenol and phenolate calculated using LRA and EOM/EFP are 1.32 and 0.89 V, respectively; they agree well with experimental values.

Formal synthesis of (-)-stemoamide using a useful epimerization at C-8 - Chavan, Subhash P.; Harale, Kishor R.; Puranik, Vedavati G.; Gawade, Rupesh L. (Tetrahedron Letters, 2012)
The formal synthesis of (-)-stemoamide was achieved starting from L-pyroglutamic acid. The key steps used are the allylation using BF3 center dot OEt2, ring closing metathesis, allylic oxidation and a novel epimerization at C8. (C) 2012 Elsevier Ltd. All rights reserved.
Keywords: Allylation; Allylic oxidation; Pyroglutamic acid; Ring closing metathesis; Stemoamide

From small aromatic molecules to functional nanostructured carbon by pulsed laser-induced photochemical stitching - Gokhale, R. R.; Thakare, V. P.; Warule, S.; Lefez, Benoit; Hannoyer, Beatrice; Jog, Jyoti Prakash; Ogale, S. B. (AIP Advances, 2012)
A novel route employing UV laser pulses (KrF Excimer, 248 nm) to cleave small aromatic molecules and stitch the generated free radicals into functional nanostructured forms of carbon is introduced. The process differs distinctly from any strategies wherein the aromatic rings are broken in the primary process. It is demonstrated that this pulsed laser-induced photochemical stitching (PLPS) process when applied to routine laboratory solvents (or toxic chemical wastes when discarded) Chlorobenzene and o-Dichlorobenzene yields Carbon Nanospheres (CNSs) comprising of graphene-like sheets assembled in onion-like configurations. This room temperature process implemented under normal laboratory conditions is versatile and clearly applicable to the whole family of haloaromatic compounds without and with additions of precursors or other nanomaterials. We further bring out its applicability for synthesis of metal-oxide based carbon nanocomposites. Copyright 2012 Author(s). This article is distributed under a Creative Commons Attribution 3.0 Unported License. [http://dx.doi.org/10.1063/1.4721268]

Functional characterization and differential expression studies of squalene synthase from Withania somnifera - Gupta, Neha; Sharma, Poonam; Kumar, R. J. Santosh; Vishwakarma, Rishi K.; Khan, Bashir Mohammad (Molecular Biology Reports, 2012)
Squalene synthase (SQS: EC 2.5.1.21) is a potential branch point regulatory enzyme and represents the first committed step to diverge the carbon flux from the main isoprenoid pathway towards sterol biosynthesis. In the present study, cloning and characterization of Withania somnifera squalene synthase (WsSQS) cDNA was investigated subsequently followed by its heterologous expression and preliminary enzyme activity. Two different types of WsSQS cDNA clones (WsSQS1and WsSQS2) were identified that contained an open reading frames of 1,236 and 1,242 bp encoding polypeptides of 412 and 414 amino acids respectively. Both WsSQS isoforms share 99 % similarity and identity with each other. WsSQS deduced amino acids sequences, when compared with SQS of other plant species, showed maximum similarity and identity with Capsicum annuum followed by Solanum tuberosum and Nicotiana tabacum. To obtain soluble recombinant enzymes, 24 hydrophobic amino acids were deleted from the carboxy terminus and expressed as 6X His-Tag fusion protein in Escherichia coli. Approximately 43 kDa recombinant protein was purified using Ni-NTA affinity chromatography and checked on SDS-PAGE. Preliminary activity of the purified enzymes was determined and the products were analyzed by gas chromatograph-mass spectrometer (GC-MS). Quantitative real-time PCR (qRT-PCR) analysis showed that WsSQS expresses more in young leaves than mature leaves, stem and root.
Keywords: Gas chromatograph-Mass Spectrometer (GC-MS); qRT-PCR; Squalene synthase; Withania somnifera

Gamma-Al2-xMxO3 +/- y (M = Ti4+ through Ga3+): potential pseudo-3D mesoporous materials with tunable acidity and electronic structure - Mathew, Thomas; Sivaranjani, Kumarsrinivasan; Gnanakumar, Edwin S.; Yamada, Yusuke; Kobayashi, Tetsuhiko; Gopinath, Chinnakonda S. (Journal of Materials Chemistry, 2012)
A simple and highly efficient surfactant-free sol-gel process has been developed to obtain nanocrystalline mesoporous gamma-Al2O3 and metal ion incorporated mesoporous gamma-Al2O3 with general formula gamma-Al2-xMxO3 +/- y (where M = Ti4+ through Ga3+). Any one of the first row transition metal (TM) ions along with Ga3+ could be introduced into the gamma-Al2O3 framework in a direct one-pot synthesis process. The generality of the present synthesis recipe for metal ion incorporation in gamma-Al2O3 was demonstrated by preparation of an Al-Ga-M ternary oxide system with the metal ion composition of general formula Al9GaTM (TM = Ti4+ to Zn2+) and their characterization through various physicochemical and spectroscopic techniques. The mesoporous gamma-Al2-xMxO3 +/- y materials showed a BET surface area in the range of 200-400 m(2) g(-1) with a narrow pore size distribution. Wormhole mesoporosity makes the material pseudo-3D (p3D) with a small pore depth of few nm (<10 nm). Metal ions in gamma-Al2O3 lead to changes in the acidity and electronic environment. XRD, TEM, and Al-27 MAS NMR studies demonstrate that the sol-gel process and the disordered mesoporous structure allow Ga and TM ions to be highly distributed and integrated in the gamma-Al2O3 framework. The efficacy of these materials in catalysis has been successfully evaluated for steam reforming of dimethylether: Ni, Cu and Zn containing Al9GaTM oxides showed high activity and stability. The smaller mesochannel depth (<10 nm) and pseudo-3D characteristics that arise due to the wormhole-type disordered mesoporous framework of these alumina materials facilitate mass transport through them without any leaching of metal ions out of the lattice and pore blocking during the reaction, which makes them attractive in catalysis. This preparation method is versatile enough to be used for a reproducible synthesis of metal ion incorporated mesoporous gamma-Al2O3 by varying the metal content and their combinations, and it is expected that many other metal ions could be introduced into the lattice framework for a variety of applications by tuning acidity and electronic structure.

Geographic variation in the flavour volatiles of alphonso mango - Kulkarni, Ram S.; Chidley, Hemangi G.; Pujari, Keshav H.; Giri, Ashok P.; Gupta, Vidya S. (Food Chemistry, 2012)
Alphonso, one of the most popular cultivars of mango in India is known to exhibit geographic variation in the flavour of ripe fruits. To get chemical insight into this difference, volatiles were studied in the ripening fruits of Alphonso mangoes from three cultivation locations in India. Ripe fruits from Deogad had lower content of mono- and sesquiterpenes and higher content of lactones and furanones as compared to the fruits from Dapoli: whereas fruits from Vengurle had average quantities of these chemicals in comparison with Deogad and Dapoli fruits. This variation was clearly reflected as separate clustering of the localities in the Principal Component Analysis. The localities were indistinguishable from each other in terms of raw fruit volatiles. This study exemplifies a case of phenotypic plasticity; since the plants chosen were clonally propagated, such geographic variation in the volatiles can be attributed to varied abiotic conditions at these three localities. (C) 2011 Elsevier Ltd. All rights reserved.
Keywords: Mango; Phenotypic plasticity; Ripening; Volatiles

Helical folding in heterogeneous foldamers without inter-residual backbone hydrogen-bonding - Priya, Gowri; Kotmale, Amol S.; Gawade, Rupesh L.; Mishra, Deepti; Pal, Sourav; Puranik, Vedavati G.; Rajamohanan, Pattuparambil R.; Sanjayan, Gangadhar J. (Chemical Communications, 2012)
This communication describes a set of hybrid foldamers that do not feature inter-residual, but intra-residual backbone hydrogen-bonding, yet adopt a preferentially folded conformation displaying right-handed helical architecture. Conformational ordering is apparently due to the combined conformational restrictions imposed by the conformationally restricted individual amino acid residues with which the oligomers are made of.

Highly diastereoselective total synthesis of (+/-)-heritonin and (+/-)-heritol - Chavan, Subhash P.; Garai, Sumanta; Kalkote, Uttam R. (Tetrahedron, 2012)
A highly diastereoselective synthesis of heritol and heritonin by intramolecular cyclization on a preformed sensitive butenolide functionality is described. (C) 2012 Elsevier Ltd. All rights reserved.
Keywords: Butenolide; cyclization; Dihydroxylation; Friedel-Crafts acylation; Tetralone

Highly efficient (R-X-R)-type carbamates as molecular transporters for cellular delivery - Patil, Kiran M.; Naik, Rangeetha J.; Rajpal; Fernandes, Moneesha; Ganguli, Munia; Kumar, Vaijayanti A. (Journal of the American Chemical Society, 2012)
The (R-X-R) motif-containing arginine-rich peptides are among the most effective cell-penetrating peptides. The replacement of amide linkages in the (R-X-R) motif by carbamate linkages as in (r-ahx-r)(4) or (r-ahx-r-r-apr-r)(2) increases the efficacy of such oligomers several-fold. Internalization of these oligomers in mammalian cell lines occurs by an energy-independent process. These oligomers show efficient delivery of biologically active plasmid DNA into CHO-K1 cells.

Highly selective and dual responsive test paper sensor of Hg2+/ Cr3+ for naked eye detection in neutral water - Das, Priyadip; Ghosh, Amrita; Bhatt, Hitesh; Das, Amitava (RSC Advances, 2012)
A highly selective and sensitive colorimetric and fluorogenic sensor (L1) for Hg2+/Cr3+ is reported. This reagent (L1) was synthesized by reacting 4-((4 (dimethylamino)phenyl)diazenyl)benzene-1-sulfonyl chloride, which has a dimethylaminophenyldiazenyl fragment as a photoactive signalling unit, with 2,2′-(3,3′-azanediylbis(propane-3,1-diyl))diisoindoline-1,3-dione as the receptor fragment. The reagent was characterized by standard analytical and spectroscopic techniques. Electronic spectral studies revealed that the reagent was selective for Hg2+ and Cr3+ in the presence of all other metal ions of Group 1A, IIA and all other common transition metal ions. On binding of L1 to the Hg2+ or Cr3+ centres, a new intense absorption band with a λmax of 509 nm appeared with associated changes in the visually detectable solution colour from yellow to red. Fluorescence spectral studies revealed a significant enhancement in the emission intensities upon coordination to Hg2+ or Cr3+ without any change in the emission wavelength. This could be explained by the efficient interruption of the photo induced electron transfer signalling mechanism involving an unshared pair of electrons from the central tertiary amine centre. An easy to prepare paper test kit, which was obtained by soaking the filter paper in a dichloromethane solution of L1, presents an approach that could be successfully used in the detection of Hg2+ or Cr3+ ions present in neutral aqueous media. This indicates the potential application of this dip strip type sensor for the detection of Hg2+ and Cr3+ in neutral aqueous environments without any spectroscopic instrumentation. Importantly, this reagent binds specifically to Cr3+ in the presence of an excess of iodide ions, which act as a masking agent for Hg2+. To the best of our knowledge, there are very few examples of detection limits lower than the present test strip for Hg2+ in the literature, while, for Cr3+, no such report is available.

Improved inhibition of telomerase by short twisted intercalating nucleic acids under molecular crowding conditions - Agarwal, Tani; Pradhan, Devranjan; Geci, Imrich; El-Madani, Amro M.; Petersen, Michael; Pedersen, Erik B.; Maiti, Souvik (Nucleic Acid Therapeutics, 2012)
Human telomeric DNA has the ability to fold into a 4-stranded G-quadruplex structure. Several G-quadruplex ligands are known to stabilize the structure and thereby inhibit telomerase activity. Such ligands have demonstrated efficient telomerase inhibition in dilute conditions, but under molecular crowding conditions mimicking physiological milieu, stabilization of the telomeric G-quadruplex is often lost. We attempted to demonstrate the enhanced G-quadruplex stabilizing ability under molecular conditions by using twisted intercalating nucleic acids (TINA)-modified oligonucleotides. We have shown using circular dichroism and ultraviolet spectroscopic methods that these TINA-modified short oligonucleotides function as G-quadruplex, inducing agents and participate in the formation of stabilized 3:1 G-quadruplex with the human telomeric oligonucleotide. Using enzyme-linked immunosorbent assay-based telomerase repeat amplification assay (TRAP) assay as well as nondenaturing polyacrylamide gel electrophoresis-based TRAP, we demonstrate remarkable enhancement in their anti-telomerase activity even under molecular crowding conditions. This is the first time in which a G-quadruplex stabilizing agent has demonstrated enhanced activity even under molecular crowding conditions.

In situ encapsulation of ultra small ceria nanoparticles stable at high temperatures in the channels of mesoporous silica - Ghosh, Sumona; Jijil, Chamundi P.; Devi, R. Nandini (Microporous and Mesoporous Materials, 2012)
Ultra small ceria nanoparticles of sizes <2 nm stable at 500 degrees C are encapsulated in the channels of mesoporous silica by employing a novel method of synthesis. The method involves modifying non-ionic polymer templates with ionic surfactants to enhance anchoring of metal ion precursors. In this way, further silica wall formation around the template ensures isolation of the nanoparticles exclusively within the channels after template removal by heat treatment. Further understanding of the interaction of the composite template system and cerium precursor is gained by cyclic voltammetric studies. (C) 2012 Elsevier Inc. All rights reserved.
Keywords: ceria; Encapsulation; Mesoporous silica; Template synthesis

In situ pH maintenance for mammalian cell cultures in shake flasks and tissue culture flasks - Pradhan, Ketaki; Pant, Tejal; Gadgil, Mugdha (Biotechnology Progress, 2012)
pH in animal cell cultures decreases due to production of metabolites like lactate. pH control via measurement and base addition is not easily possible in small-scale culture formats like tissue-culture flasks and shake flasks. A hydrogel-based system is reported for in situ pH maintenance without pH measurement in such formats, and is demonstrated to maintain pH between 6.8 and 7.2 for a suspension CHO cell line in CD CHO medium and between 7.3 and 7.5 for adherent A549 cells in DMEM:F12 containing 10% FBS. This system for pH maintenance, along with our previous report of hydrogels for controlled nutrient delivery in shake flasks can allow shake flasks to better mimic bioreactor-based fed batch operation for initial screening during cell line and process development for recombinant protein production in mammalian cells. (C) 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Keywords: high throughput screening; pH control for cell culture; pH control in shake flask; pH control in tissue culture flasks; small scale platforms for cell culture