Effect of amino compounds on alkaline amylase production by alkalophilic Bacillus sp.

Abstract

Of the amino compounds investigated, β-alanine, dl-norvaline and d-methionine were effective for the production of alkaline amylase by alkalophilic Bacillus no. A-40-2. The addition of 0.5% dl-norvaline and 0.5% d-methionine to the culture medium increased amylase production 1.7-fold, while they repressed growth slightly or strongly. There was no relation between amylase yield and the extracellular protein amount. Because alkaline protease activity was negligible in the culture fluid, these compounds might change the regulation of amylase synthesis and/or make amylase excretion easier.