@article {44186, title = {Streptomyces sp metabolite(s) promotes Bax mediated intrinsic apoptosis and autophagy involving inhibition of mTOR pathway in cervical cancer cell lines}, journal = {Scientific Reports}, volume = {8}, year = {2018}, month = {FEB}, pages = {2810}, type = {Article}, abstract = {

In cervical cancer, the association between HPV infection and dysregulation of phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway (PI3K/AKT/mTOR pathway) places mTOR as an attractive therapeutic target. The failure of current treatment modalities in advanced stages of this cancer and drawbacks of already available mTOR inhibitors demand for novel drug candidates. In the present study we identified the presence of a mTOR inhibitor in an active fraction of the ethyl acetate extract of Streptomyces sp OA293. The metabolites(s) in the active fraction completely inhibited mTORC1 and thereby suppressed activation of both of its downstream targets, 4E-BP1 and P70S6k, in cervical cancer cells. In addition, it also stalled Akt activation via inhibition of mTORC2. The mechanism of mTOR inhibition detailed in our study overcomes significant drawbacks of well known mTOR inhibitors such as rapamycin and rapalogs. The active fraction induced autophagy and Bax mediated apoptosis suggesting that mTOR inhibition resulted in programmed cell death of cancer cells. The molecular weight determination of the components in active fraction confirmed the absence of any previously known natural mTOR inhibitor. This is the first report of complete mTOR complex inhibition by a product derived from microbial source.

}, issn = {2045-2322}, doi = {10.1038/s41598-018-21249-5}, author = {Dan, Vipin Mohan and Muralikrishnan, Balaji and Sanawar, Rahul and Vinodh, J. S. and Burkul, Bhushan Bapusaheb and Srinivas, Kalanghad Puthankalam and Lekshmi, Asha and Pradeep, N. S. and Dastager, Syed G. and Santhakumari, B. and Santhoshkumar, Thankayyan R. and Kumar, R. Ajay and Pillai, Madhavan Radhakrishna} } @article {46712, title = {Structural and electrical characterization studies for ternary composite of polypyrrole}, journal = {Journal of Materials Science-Materials in Electronics}, volume = {31}, year = {2020}, month = {NOV}, pages = {18400-18411}, type = {Article}, abstract = {

In this work, temperature dependence of alternate current (AC) and direct current (DC) conductivities of optimized polypyrrole/silver-tantalum oxide (PPy/Ag-Ta2O5), a ternary conducting polymer composite is comparatively studied with those of PPy and PPy/Ag. For the purpose, silver (Ag) nanoparticles were encapsulated with polypyrrole (PPy) by in situ oxidative polymerization to form core-shell structured PPy/Ag composite for which Ag nanoparticles were extracted from green tea. The PPy/Ag composite was then mechanically mixed with tantalum pentoxide (Ta2O5) to form PPy/Ag-Ta(2)O(5)ternary composite. Increase in depth of delocalization band of PPy in ternary composite as compared to those of PPy/Ag composite and PPy, indicating its increased AC conductivity confirmed from the comparative FTIR analyses. Interaction between PPy/Ag composite and Ta(2)O(5)in the ternary composite was confirmed from XRD studies. The formation of core-shell structured PPy/Ag composite and Ta(2)O(5)particles embedded in such PPy/Ag composite to form PPy/Ag-Ta(2)O(5)ternary composite confirmed from TEM and Raman studies. The frequency- and temperature-dependent electrical conductivity studies revealed increase in AC conductivity of the ternary composite as compared to those of PPy/Ag composite and pure PPy attributed mainly to interfacial effects. The charge transport in these samples predicted to be due to correlated barrier hopping of charges was confirmed by calculating their respective AC and DC activation energies.

}, issn = {0957-4522}, doi = {10.1007/s10854-020-04386-4, Early Access Date = SEP 2020}, author = {Megha, R. and Ravikiran, Y. T. and Kumari, S. C. Vijaya and Prakash, H. G. Raj and Revanasiddappa, M. and Manjunatha, S. and Dastager, Syed G. and Thomas, S.} } @article {48966, title = {Strain improvement for enhanced erythritol production by Moniliella pollinis Mutant-58 using jaggery as a cost-effective substrate}, journal = {International Microbiology }, volume = {27}, year = {2024}, month = {APR}, pages = {581-596}, type = {Article}, abstract = {

Erythritol has been produced by various microorganisms including Yarrowia, Moniliella, Aureobasidium, and Candida strains. Due to its relatively high price, erythritol sweetener is used lesser than other polyols despite having many advantages. Therefore, in this study, Moniliella pollinis strain was improved for erythritol production by chemical mutagenesis and subsequently screening for cost-effective carbon sources for the enhanced erythritol yield. M. pollinis was subjected to N-methyl N-nitro N-nitroso guanidine (NTG), ethyl methyl sulfonate (EMS), and UV mutagenesis for improved erythritol production. The fmutant strains were evaluated for enhanced erythritol production medium optimization by using different carbon substrates at the shake flask level. To enhance the production of erythritol and statistical media, optimization was carried out using a central composite design (CCD). Among 198 isolated mutants, Mutant-58 strain generated by EMS mutagenesis was selected for further assessment. The Mutant-58 strain showed significant morphological changes as compared to the parent strain. Furthermore, statistically optimized media composition resulted in the higher production of erythritol (91.2 \& PLUSMN; 3.4 g/L) with a yield of 40.7 \& PLUSMN; 3.4 \% in shake flask experiments. The optimized medium composition for erythritol production constitutes (g/L) 225 jaggery, 4.4 yeast extract (YE), 4.4 KH2PO4, 0.31 MgSO4, and pH 5.5. The present study demonstrated strain improvement, media, and process optimization resulting in a 30\% increase in the erythritol production in the Mutant-58 as compared to the parent strain. This is also the first instance where jaggery has been used as a cost-effective carbon source alternative to glucose for industrial-scale erythritol production.

}, keywords = {Erythritol, Fermentation, Moniliella pollinis, Mutation, Optimization, renewable resource}, issn = {1139-6709}, doi = {10.1007/s10123-023-00411-8}, author = {Khatape, Anil B. and Rangaswamy, Vidhya and Dastager, Syed G.} } @article {49956, title = {Stimulant immobilized bioactive film of functionalized egg albumin blend for wound healing}, journal = {International Journal of Pharmaceutics}, volume = {682}, year = {2025}, month = {SEP }, pages = {125896}, type = {Article}, abstract = {

Wound healing materials with advanced properties that facilitates higher collagen deposition, improved angiogenesis and quick tissue regeneration are crucial for clinical wound management. To meet the requirement, for the first time, our studies focus on engineering bio-originated natural materials, which are tested in combination with the active agents, ascorbic acid (AA), a stimulant and metronidazole (Mtz), an anti-microbial drug. Accordingly, a dual drug (AA, and Mtz) loaded film of functionalized egg albumin (FEA)-poly(vinyl alcohol) (PVA) was fabricated following the solution casting method. The film was characterized for its morphology and physicochemical properties using various analytical tools. The potential of the film as a wound healing material was evaluated, by in vitro drug release, degradation, cell viability, antimicrobial studies, in vivo wound healing, and histopathological analyses. In vitro degradation studies confirmed their degradability in enzymatic and soil burial conditions. Cytotoxicity studies demonstrated their non-toxicity, and the antimicrobial investigations showcased that the material was antibacterial. On the 14th day, the wound closure percentage of the wound induced control group, GI (without treatment) was notably higher at 95 \% compared to the test formulation group, GV [FEA-PVA (30/70 w/w) loaded with Mtz and AA (10 \% w/w of the total polymer weight), respectively], which exhibited a wound closure of 83 \%. Furthermore, the histopathological examinations revealed that the inner wound healing in GV was comparatively better than in GI in terms of angiogenesis, epidermal remodeling, higher collagen deposition, coherency, and tissue regeneration. Consequently, the formulated film can be deemed a suitable wound dressing material.

}, keywords = {collagen, Dual drug release, Functionalized egg albumin, Polymer blend films, Stimulant, wound Healing}, issn = {0378-5173}, doi = {10.1016/j.ijpharm.2025.125896}, author = {Gautam, Tripurari Rao and Patel, Pratikshkumar R. and Singam, Amarnath R. and Jagtap, Ashish S. and Desai, Prasad and Gundloori, Rathna V. N. and Pawar, Anil and Dastager, Syed G.} }