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Microbial biotransformation is an efficient process for making high-value natural products in a controlled and environment friendly manner. Bioconversion of low value monoterpenes to high value products using fungi offers an effective strategy for producing desirable products. Efficient conversion of D-limonene, a monoterpene, into carveol is reported in this study by using an endophytic fungus, Aspergillus flavus IIIMF4012, isolated from the root of Rosa damascena. By optimizing different parameters, isolated strain resulted in the hydroxylation of D-limonene to carveol effectively and the process was carried out at 1 L scale which resulted in the formation of a mixture of carveol isomers (cis- carveol 23.82%, trans- carveol 17.21%). Further, the biotransformation was scaled up in 5 L fermenter and the product was characterized by GC-MS and NMR (1H & 13C). As a result, an efficient procedure was established for biotransforming a low-value molecule i.e., D-limonene into a high-value product i.e.,carveol. [ABSTRACT FROM AUTHOR]

Natural value-added compounds produced from biological sources have attained immense significance in medicinal, food, flavourings, and agrochemical industries. Further, biotransformation is a powerful tool used to produce value-added compounds cost-effectively and selectively. In the present study, biotransformation of eugenol using an endophytic fungus Daldinia sp. IIIMF4010 isolated from the fresh leaves of the plant Rosmarinus officinalis leads to the production of two known value-added compounds. The biotransformation reaction of eugenol (50 mM) resulted in the production of eugenol-β-D-glucopyranoside (6.2%) and vanillin (21.8%). These biotransformed products were further characterized by liquid chromatography-mass spectroscopy (LC-MS) and nuclear magnetic resonance (NMR). [ABSTRACT FROM AUTHOR]

Myxobacteria have emerged as a rich manufacturer of a wide array of natural products captivating both the academic and drug discovery communities. Attempts to unearth novel bioactive, myxobacteria from unexploited habitats are far from exhaustion. This study reports the isolation of myxobacteria from dung pellets collected from various regions of northwestern Himalayas. The isolated myxobacteria were functionally characterized to evaluate their bioactive capability. Of all the isolates, ST/P/71 exhibited broad range activities such as anticancer against all the four human cancer cell lines with IC50 in range of 2.03–9.65 µg/ml, antimicrobial against all the tested human pathogens, also exhibiting biofilm inhibition with MBIC50 at 10.4 µg/ml against Salmonella typhimurium. Consequently, ST/P/71 was chosen for fermentation and isolation of bioactive secondary metabolite through semi‐preparative HPLC. It yielded compound 1, characterized as di‐isobutyl phthalate (DiBP) based on nuclear magnetic resonance (NMR) and mass data. DiBP exhibited promising cytotoxic activity against the lung cancer cell line (A549) at an IC50 values 3.09 µg/ml and biofilm inhibition activity against Bacillus subtilis and Salmonella typhimurium with MBIC50 2.703 and 9.263 µg/ml, respectively. ST/P/71 was identified as Myxococcus fulvus. Thus, M. fulvus ST/P/71 isolated from northwestern Himalayas is a new source of DiBP. [ABSTRACT FROM AUTHOR]

Acetohydroxamic acid is a pharmaceutically active metal chelating agent which has various applications in the field of medicine. Current study focuses on the enzymatic synthesis of acetohydroxamic acid catalysed by thermophilic amidase from Bacillus smithii IIIMB2907. Bacterial cells were grown in 7 L fermenter for amidase production and effect of pH, temperature and substrate concentration for the biotransformation of acetamide to acetohydroxamic acid was studied. Batch reaction was also successfully optimized at bench scale with the recovery of ≈ 81% acetohydroxamic acid (purified). [ABSTRACT FROM AUTHOR]

Till date, amidases from halophiles and halotolerant micro-organisms have not been much explored. In the present study, Brevibacterium sp. IIIMB2706 strain was isolated from salt fields of Gujarat, India, using propionitrile as a nitrogen source in the mineral base media and explored for its amidase activity. Amidase from Brevibacterium sp. IIIMB2706 exhibited substrate affinity towards isobutyramide, propionamide and butyramide. The optimum temperature and pH required for its maximum activity was 45 °C and 7.0, respectively. Effect of salt concentration on amidase activity was also studied and maximum activity was observed in presence of 50 g L−1 NaCl with significant activity up to 200 g L−1 NaCl which justifies its halotolerant nature. Various organic solvents compatibility profile showed that the enzyme was highly active in presence of 10% methyl alcohol. Henceforth, halotolerant enzymes may find application in industrial processes where substrate requires organic solvents for solubilization. [ABSTRACT FROM AUTHOR]