Nutritional Enzymes Inhibitory Activities of Fruit Juice and Fruit Pulp Extract of Muntingia Calabura L.

Abstract

The fruit of Kersen or cherry (Muntingia calabura), a popular shade tree, is not yet promoted as a marketable fruit or a healthy herbal drink. This study aimed to investigate potential health benefits of fruit juice and crude extract of the fruit pulp of M. calabura including their antioxidant potential and inhibitory activities on several enzymes related to metabolic disorders. Fresh juice (FJ) of M.calabura fruit was obtained by juice extractor, whereas the fruit pulp (FP) was dried and macerated with ethanol to obtain the crude extract. Both were evaluated for their inhibitory activities against α-glucosidase, α-amylase, xanthine oxidase, lipase, and protease. Antioxidant activity was evaluated based on their scavenging activity on 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radicals. Both FJ and FP showed good antidiabetic activity by inhibiting α-glucosidase (IC50 162.00 and 84.70 µg/mL, respectively) and α-amylase (IC50 422.34 and 80.46 µg/mL, respectively). In comparison, IC50 of acarbose on α-glucosidase and α-amylase were 130.66 and 152.46 µg/mL, respectively. The FJ and FP extract showed anti-hyperuricemia activity by inhibiting xanthine oxidase (0.02 and 2.78 mg allopurinol equivalent/mL for FJ and FP, respectively). However, weak inhibition activities on protease and lipase were observed for the FJ and FP extract compared to the references used. Similarly, FJ and FP exhibited weak scavenging activity on DPPH, when compared with BHT and ascorbic acid. The study recommends the fruit of M.calabura as a potential source of antidiabetic and anti-hyperuricemia agents. The fruit can be further explored for nutraceutical applications.