Isolation, Optimization and Characterization of alpha Amylase from Bacillus Alcalophilus

Amylase is one of the most important enzymes widely used in paper, textile, pharmaceutical industries etc. In the present investigation a thermostable, alkalophilic amylase was isolated from underlying soil samples of domestic wastes, and was screened on starch agar medium. The amylase activity was measured using colorimetric method at 540nm. Among forty five isolates, thirteen demonstrated clear zone of hydrolysis around the colonies when flooded with Grams iodine solution. Maximum zone of hydrolysis was 8 mm, and tentatively identified as Bacillus alcalophilus. Its maximum activity was 9.210 + 0.14 U/ml at pH 9 and 80C temperature. It retains 70 % activity after 1 h at 80C and 60 % activity after 1 hour at 90C. With these promising features B. alcalophilus may be utilized in starch processing, detergent manufacturing brewing, and sugar production.