Abstract
Department of Food Science and Technology, Faculty of Agriculture, Kyushu University, Fukuoka Japan At least, four kinds of amylase inhibitors are found in culture of Streptomyces sp. No.280.1) A large amount of amylase inhibitors were produced by Streptomyces sp. No. 280 when cul-tivated on 3% oatmeal medium and it was found that the molecular weight of the inhibitors were transformed to smaller molecules during the cultivation time. The transformation of the amylase inhibitor was found to result from degradation of its carbohydrate moiety by α-amylase in the culture broth. The amylase inhibitor was hydrolyzed partially by the action of taka-amylase A or hog pancreatic α-amylase. With hydrolyzation of amylase inhibitor by α-amylase, neutral sugars (mainly maltose) were liberated from the amylase inhibitor and a modified inhibitor was newly formed, but amylase inhibitory activity against glucoamylase was not changed. The inhibitory activity against muscle phosphorylase a, however, was almost completely lost.
