Effects of Bay m 1099, an α-Glucosidase Inhibitor, on Starch Degradation in Germinating Mung Beans

To examine the mechanism of starch degradation in legume cotyledons and the physiological role of α-glucosidase, mung bean seeds were germinated in the presence of Bay m 1099, an α-glucosidase inhibitor. Bay m 1099 (10 μg/ml medium), which minimized the growth deterioration of the mung bean seedlings, caused no changes in the overall rate of starch degradation and of soluble carbohydrate production in the cotyledons, although α-glucosidase activity had been completely suppressed. Total amylase and phosphorylase activities were not influenced by Bay m 1099. These results suggest that the mung bean α-glucosidase is less responsible for starch degradation, unlike wheat α-glucosidase [Konishi et al., Biosci. Biotech. Biochem., 58, 135-139 (1994)].