Rat Intestinal α-Glucosidase Inhibitory Activities of Leguminous Seed Extracts

The methanol extracts of 25 leguminous seeds in vitro was evaluated for inhibitory activities against the small intestinal $\alpha$-glucosidase of Sprague Dawley male rats. The responses varied both with leguminous seed types and concentrations used. At the concentration of 0.5 mg/ml, the methanol extracts of Cassia obtusifolia, Glycine max var. yagkong, Glycine max var. hooktae, Glycine max var. geumdu, Glycine max var. mejukong, Glycine soja, Phaseolus multiflorus, Pisum sativum, and Vigna sinensis inhibited over 50% of the enzyme activity. The extracts of G. max var. yagkong and V. sinensis showed relatively strong inhibitory activities against $\alpha$-glucosidase at the concentration of 0.1 mg/ml. The activity of each solvent fraction from G. max var. yagkong and V. sinensis was determined, and potent activities were detected from chloroform and butanol fractions, respectively. $IC_{50}$ values of G. max var. yagkong and V. sinensis were 0.06 and 0.19 mg/ml, respectively. As a naturally occurring therapeutic agents, leguminous seeds examined could be useful for developing new types of antidiabetic agents.