Isolation and characterization of a thermostable -amylase from Bacillus subtilis

Abstract

The present study is aimed at assessing the ability of Bacillus subtilis to convert starch into reducing sugars. Maximum enzyme activity showed by B. subtilis was 236 Uml -1 . B. subtilis showed optimum growth at pH 8 and optimum temperature for the growth of bacterial isolate was found to be 45°C. The optimal pH and temperature of the amylase activity were 7.0 and 37°C, respectively. The enzyme was found to be stable in the pH range of 5 to 10. Maximum -amylase activity was determined in 1% starch. The enzyme was found to be in two forms with relative molecular mass of 43 and 18 kDa in SDS-polyacrylamide gel electrophoresis. B. subtilis can be exploited for starch conversion biotechnologies.