Pectinase Producing Bacteria Isolation from Halophilic Soil, Water Samples and Partial Purification of the Enzyme

Abstract

Pectinases are protease enzymes capable of degrading pectin, which is one of the most important polysaccharide found in nature. Pectinase enzymes find uses in paper-pulp industry, textile industry, food industry and other industries where lignocellulosic material is utilized. Commercially pectinase enzymes are obtained from bacterial and fungal culture grown on decaying fruits and vegetables. In the present study, an attempt was made to isolate pectinase producing bacteria growing in halophilic conditions. Soil (sand) and water samples containing high concentrations of salts from beaches of Taiwan and Karwar, Karnataka were collected and screened for pectinase activity using modified M9 media. Among the obtained 16 bacterial strains, strain 15 showed the highest pectinase activity during screening and was identified to be a Bacillus sp. from morphological features and biochemical tests. This strain was selected and its cultural conditions were standardized for maximum production of pectinase enzyme. Maximum enzyme activity was obtained at pH 11, temperature 40°C, and incubation period of 24 hours. To enhance the productivity modification were tried out in culture media related to nitrogen source and carbon source in which the nitrogen source did not have any significance in activity of enzyme but glucose seemed to be the best carbon source for the growth of bacteria. Further the obtained enzyme was partially purified using the salting out method, dialysis followed by desalting, gel filtration chromatography and ion-exchange chromatography.