Sodium alginate preparation (average of m.w.>300,000) wasdepolymerized by incubation with Vibrio alginolyticus SUN53(NITE-P-14) isolated from marine bacteria in sandy beach ofNagasaki by Ueda. The lyophilized powder of depolymerized productof sodium alginate, of which molecular weight was approximately1,000, was obtained. The solution of the product inhibited theactivities of sucrase, maltase, isomaltase, lactase, and trehalaseusing rat intestinal brush border membrane vesicles. By theaddition of the depolymerized sodium alginate, sucrase and lactase,maltase, and isomaltase were inhibited approximately 60%, 35%, and45%, respectively. These inhibitory effects depended on theconcentration of the product. However, trehalase was not so clearlyinhibited. These inhibitory modes were competitive byLineweaver-Burk plot. These results suggest that the depolymelizedsodium alginate by Vibrio alginolyticus SUN53 could contribute todevelop the ingredient, which have the possibility of thesuppressive effect of postprandial blood glucose levels.

Key words: depolymerized sodium alginate, inhibition, intestinaldisaccharidase, rat