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Of 450 Strains isolated from the soil microbes collected in various locations in Korea, a strain had a strong inhibitory activity against bacterial α-amylase and was named strain DMC-72 of the genus Streptomyces. The amylase-inhibitory metabolite produced by this strain was purified by means of acetone precipitation, adsorption on Amberlite IRC-50 and XAD-8, and column chromatography on Amberlite CG-50 and SP-sephadex C-25. The inhibitor which was stable at the pH range of 1∼13 and at 100℃ for half an hour also inhibited other amylases such as salivary α-amylase, pancreatic α-amylase, fungal α-amylase and glucoamylase, but it showed no inhibitory activity against α-glucosidase, β-glucosidase, dextranase and β-amylase. The kinetic studies of the inhibitor showed that its inhibitory effects on starch hydrolysis by α-amylase were non-competitive.
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