PURIFICATION AND CHARACTERIZATION OF EXTRACELLULAR LIPASE PRODUCED BY BACTERIAL STRAIN ISOLATED FROM OIL CONTAMINATED SOIL

Abstract

Microbes are most important part of the soil. In a very little amount of soil billions of microbes are present and performing their role. Soil bacteria which produces lipase enzyme are very crucial to the industrial applications. These enzymes catalyzed the hydrolysis of free fatty acids and glycerol’s. These enzymes show regiospecificity and anantioselectivity properties. In this study isolation, partial purification, characterization and optimization of lipase enzymes was studied. Isolation was done by serial dilution. After partial purification molecular weight of the lipase was determined by SDS-PAGE. To find out the enzyme characterization spectrophotometric lipase assay was applied. After screening the enzyme samples were selected for the characterization and purification studies. Different plant oils were used to observe the enzyme activity. Highest lipase enzyme activity was observed in the presence of canola oil. Lipase enzyme activity at different pH was measured and best results were observed at neutral and alkaline pH values pH 7.0 and pH 9.0. Enzyme activity under different metal salts was observed and there was decreased lipase activity in the presence of Nickle acetate and lead as compared to copper and cobalt. Copper cause 80% increase in enzyme activity. The activity of lipase enzyme was increased in presence of ethanol. Under different incubation periods Maximum activity was observed at 48 hrs of incubation period and minimum was observed at 24 hrs of incubation period. After 48 hours there was gradual decrease in the in the lipase enzyme activity.