CHARACTERIZATION OF POTENT EXOPOLYSACCHARIDE PRODUCING BACTERIA ISOLATED FROM FRUIT PULP AND POTATO PEELS AND ENHANCEMENT IN THEIR EXOPOLYSACCHARIDE PRODUCTION POTENTIAL

Abstract

Exopolysaccharides (EPS) are environment friendly natural polymers secreted by microorganisms in the surrounding medium. Due to the presence of unique structural composition, EPS shows diverse applications such as in food formulations, pharmaceutical, cosmetics industry, etc. In the present investigation for the isolation of EPS producing bacteria, 30 samples comprising 14 fresh fruits, 14 spoiled fruits, 1fresh potato peels and 1spoiled potato peels were inoculated on 4 different solid media containing sucrose, glucose and galactose as carbohydrate substrate and MRS agar (MRSA). The bacteria producing higher exopolysaccharide were screened among bacteria isolated from fresh and spoiled fruits and potato peels. Total 105 EPS producing colonies were obtained, out of which 17 isolates, which showed viscosity more than 0.1060m.Pa.S-1 were selected. Based on 16S rRNA gene sequence analysis, 17 isolates, which represents 8 genera, out of this 40% isolates belong to genera Bacillus. Among the carbohydrate studied sucrose proved to be the choice of the isolates for EPS production as compared to other sugars. When SYE and EPS media were compared, EPS medium was found to be the best except for the isolate SR17. The selection of EPS medium as medium of choice, sucrose as source of sugar and its 5% concentration in the medium enhanced EPS production as high as 440% higher as compared to SYE medium.