THE IN VITRO INHIBITORY ACTIVITY OF THE CARBOHYDRATE METABOLIZING ENZYME (ALPHA AMYLASE) IN THE AQUEOUS PULP AND PEEL EXTRACT OF OSU FRUIT (PICRALIMA NITIDA)

ABSTRACT

The control of postprandial glucose is important in the management of diabetes mellitus. Alpha amylase is an enzyme involved in starch hydrolysis which digest the carbohydrates and increase the postprandial glucose level in diabetic patients. The inhibition of α-amylase is one of the most effective anti-diabetic approaches used to control postprandial hyperglycemia and used in the reduction of the risk of diabetes. Research have shown that plants play a vital role in controlling hyperglycemia. The present study was designed to investigate the effect of aqueous pulp extract of Picralima nitida on the in vitro inhibitory activity of α-amylase. The result showed that α-amylase was mildly inhibited (with an IC₅₀ of 38.15µg/ml) in a dose-dependent manner by the pulp and bark extract of Picralima nitida. Acarbose was used as a positive control. The in vitro inhibitory activity of acarbose was stronger in comparison to Picralima nitida’s pulp and peel extract. Therefore, the ‘supposed’ control of hyperglycemia with the aqueous extract of Picralima nitida might be through other mechanisms but not by the inhibition of α-amylase.