Identification and biotechnological potential of psychrotrophic marine isolates

Background: Importance of microbial metabolites in food, detergent, pharmaceutical, nutraceutical and cosmetic industries has now been widely established. To fulfill the requirement of these industries, psychrophilic/psychrotrophic marine microbes are being explored. These microbes help in the production of metabolites that are active and stable at extreme physiological conditions. In correlation with this scenario, the present study reports identification of 14 bacterial isolates (BRI 32- BRI 45) from marine water samples (out of which 4 are Antarctic) with emphasis on their biotechnologically important characters. Material and Methods: Bacterial isolates were identified using 16S rRNA gene sequencing. Growth of the isolates under different physiological conditions of temperature (10°C to 45°C), pH (3-10) and concentration of NaCI (0-20%) was studied. Further, the isolates were examined for their ability to produce i) polyunsaturated fatty acids, ii) industrially important enzymes and their potential to produce bio-surfactant. Results: 16S rRNA gene sequence analysis revealed that the isolates belonged to Halomonas, Brevibacillus, Kocuria and Oceanobacillus genera. Our results indicated that the isolates could grow over a wide range of physiological conditions of pH (3-10), temperature (10-45°C) and NaCI concentration. Eight out of 14 isolates showed the presence of omega-3 and omega-6 fatty acids. BRI 34 was found to produce significant amounts of eicosapentaenoic acid (39.66%). Most of the isolates exhibited the ability to produce 3 or 4 enzymes. Only BRI 35 showed potential for biosurfactant production. Conclusions: Our findings suggest potential of these isolates for biotechnological applications.