To develop anti-acidosis and anti-diabetes agentsfrom natural products, the inhibitory activities of Brazilian plant extracts against microbial -amylase and -glucosidase were evaluated. Among 100 different ethanol extracts tested, those of Acacia jurema Mart., Anacardium humile A. St.-Hil., Cedrela odorata L., and Guazuma ulmifolia Lam showed good inhibitoryactivities toward both enzymes. In addition, an extract of Plumeria drastica Mart. showed specific inhibition of -amylase, whereas that of Eugenia uniflora L. demonstrated strong inhibition of the enzyme. IC50 values of -amylase inhibition suggested that the extract of A. humile A. St.-Hil., which has been used as an anti-diabetes medicine in Brazil, had potent inhibitory activity. The IC50 for the A. humile A. St.-Hil. extract () was similar to that of acarbose (). This activity of A. humile A. St.-Hil. was not reduced by heat or acid treatment. Moreover, treatment with HCl (0.01 M) for 1 h increased the inhibitory activity from 57.5% to 81.2%. Also, the extract did not cause hemolysis of human red blood cells at levels up to 1 mg/mL. The results indicate that the extract of A. humile A. St.-Hil. is potentially useful as an anti-acidosis and anti-diabetes agent.

To investigate characterization of the -amylase inhibitors from cereals and legumes produced in Korea, inhibitory activities against -amylase with the inhibitor from barley(Hordeum vulgare), wheat(Triticum aestivun), black bean(Glycine max), bean(Cajanus cajon) and pea(Pisum sativum) were measured. Among the samples tested, inhibitors from naked barley and black bean(sabong) which showed the highest inhibitor activities of cereals and legumes, respectively, were characterized according to treatment condition. The results obtained were summarized as follows. During the germination of naked barley and black bean, -amylase activities were gradually increased but inhibitory activities against -amylases were decreased. Both activities were gradually decreased when naked barley and black bean were stored. More than 50% of activities of the inhibitors from naked barley and black bean were remained at 100 for 15 min and 20 min, respectively, indicating that the inhibitor from black bean was more stable to heat than that of barley.