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Most bacteria and their enzymes are destroyed or inactivated in the presence of organic solvents. Organic solvent tolerant bacteria are a relatively novel group of extremophilic microorganisms that combat these destructive effects and thrive in the presence of high concentrations of organic solvents as a result of various adaptations. These bacteria are being explored for their potential in industrial and environmental biotechnology, since their enzymes retain activity in the presence of toxic solvents. This property could be exploited to carry out bioremediation and biocatalysis in the presence of an organic phase. Because a large number of substrates used in industrial chemistry, such as steroids, are water-insoluble, their bioconversion rates are affected by poor dissolution in water. This problem can be overcome by carrying out the process in a biphasic organic-aqueous fermentation system, wherein the substrate is dissolved in the organic phase and provided to cells present in the aqueous phase. In bioprocessing of fine chemicals such as cis-diols and epoxides using such cultures, organic solvents can be used to extract a toxic product from the aqueous phase, thereby improving the efficiency of the process. Bacterial strains reported to grow on and utilize saturated concentrations of organic solvents such as toluene can revolutionize the removal of such pollutants. It is now known that enzymes display striking new properties in the presence of organic solvents. The role of solvent-stable enzymes in nonaqueous biocatalysis needs to be explored and could result in novel applications.

Steroid transformation is of great importance in the pharmaceutical industry. The major limiting factor in this process is the extremely poor solubility of steroids in aqueous media, which lowers their transformation rate and increases costs. This problem can be overcome by using organic-solvent-tolerant bacteria (OSTB), which can carry out the desired bioconversions in an organic-solvent-saturated system. OSTB are a relatively novel group of extremophilic microbes that have developed various adaptations to withstand solvent toxicity. The aim of this study was to isolate marine bacteria producing organic-solvent-stable cholesterol-transforming enzymes. A Bacillus species, BC1, isolated from Arabian Sea sediment was found to degrade cholesterol and exhibit excellent solvent tolerance particularly to chloroform. OSTB have tremendous potential in industrial processes involving nonaqueous biocatalysis and transformation in the presence of an organic phase.

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Background: Bioenzymes are organic products of fermentation of fruits/vegetables waste which have shown promising antimicrobial activity against a wide range of pathogenic microorganisms. Following fermentation, the antibacterial properties of these Bioenzymes are enhanced multi-fold as organic substances after decomposing,yield bioactive compounds or phytochemicals. Aim: To evaluate the antimicrobial potency of Bioenzymes prepared using Emblica officinalis (Amla) fruit, Cucumis sativus (Cucumber) peel and Hibiscus Rosa-sinensis (Hibiscus) petal and a mixture of all three. Method: 4 Types of Bioenzymes were prepared, 3 of them prepared using Amla, Hibiscus, Cucumber individually while the fourth one having equal parts of all three plant parts. These 4 types of Bioenzymes were prepared in two sets namely Set I (fermented for 12 weeks) and Set II (fermented for 25 days). All of these eight test samples were subjected to antimicrobial susceptibility testing, using the Agar well diffusion method against 5 Bacterial strains. Result: It was observed that Bioenzymes from both these sets were capable of successfully producing large zone of inhibition. Bioenzymes from Set I were also analysed to determine their Minimum Inhibitory Concentration against S. aureus and it was observed that Amla Bioenzyme Set I and Mixture Bioenzyme Set I was found to be at 50% concentration. Conclusion: The Bioenzymes have shown the potential to act as promising antimicrobial agents against various pathogenic bacteria.