The α-glucosidase and α-amylase inhibitory activity from different chili pepper extracts

Abstract

Diabetes is nowadays one of the leading causes of death among all health problems. Control of some key enzymes involving in starch degradation is considered a model pathway for new drug discovery for treatment/prevention of diabetes. Chili peppers have been demonstrated the ability to control diabetes through inactivation of α-glucosidase and α-amylase, the key enzymes that hydrolyze polysaccharide into glucose. The purpose of this experiment was to compare α-glucosidase and α-amylase inhibitory activities of different commercially available chili peppers in Thailand, including 'Yellow pepper', 'Bird chili', 'Green pepper', 'Cayenne Pepper', 'Red Chinda pepper', 'Green Chinda pepper', 'Young pepper', 'Chili Spur pepper' and 'Sweet pepper'. As results, 70% (v/v) aqueous ethanolic extracted chili peppers (5 mg/mL) exhibited anti-α-glucosidase activities within the range of 23-66% inhibition with Sweet pepper and Cayenne Pepper providing the highest and the lowest inhibitory activities, respectively. On the other hand, all chili peppers exhibited anti-α-amylase activities within the range of 27-58% inhibition with Green Chinda pepper and Sweet pepper providing the highest and the lowest inhibitory activities, respectively. Both enzyme inhibitions were dose-dependent, in which the inhibition was elevated as increasing concentration of chili pepper extract. Besides, these enzyme inhibitions were independent to fruit maturity but instead chili pepper species. Thus, chili peppers might be potential sources of natural products against diabetes and obesity through inhibition of α-glucosidase and α-amylase for future development of functional food, nutraceuticals or dietary supplement.