ANTIDIABETIC ACTIVITY OF MAHKOTA DEWA STEM EXTRACTS AS INHIBITOR OF ALPHA-GLUCOSIDASE

Alpha-glucosidase (EC 3.2.1.20) was carbohydrase that catalyzes the liberation of a-glucose from the nonreducing end of the diet carbohydrate. In diabetic patients, inhibition of these enzymes cau se restrain of glucose absorption and decrease the postprandial hypergIycemia. The purpose of this research was to study the antidiabetic activity of mahkota dewa [Phaleria macrocarpa (Scheff.) Boerl.l stem extracts by inhibition assay to alpha glucosidase enzyme. This research was condueted in three steps: fractionation and extraction samples with methanol, ethyl acetate, n-butanol and water, followed by phytochemistry screening and alpha-glucosidase inhibitlon assay. The alpha-glucosidase inhibition assay was performed by using alpha-glucosidase enzyme and p-nitrophenyl a-D-glucopyranoside as a substrate. The phytochernistry screening showed that Mahkota Dewa stem extracts contained phenolics, thanins, flavonoids, alkaloids and carbohydrates compounds. The alpha-gIucosidase inhibition assay showed that at 50 ppm, inhibition activity from the ethyl acetate fraction extraet of young stem (40.86%) was higher than old stem C35.22%). The inhibition activity from the n-butanol fraction extraet of young stem (34.74%) was higher than old stem (2.57%), but for the bolled water extraets, inhibition activity from old stem (18.07%) was higher than young stem (11.38%). The methanol extract and the water fraction extract didn't have inhibition activity.