Phenolic profiles, antioxidant, antiproliferative, and hypoglycemic activities of Ehretia macrophyla Wall. (EMW) fruit

Phenolic profiles, antioxidant, antiproliferative, and hypoglycemic activities of the whole Ehretia macrophylla Wall. (EMW) fruit were investigated in the present study. Catechin (CE), o-methoxy benzoic acid (o-MBA), and rosmarinic acid (RA) were the predominant phenolics in free extract, while CE, vanillic acid (VA), and o-MBA were for bound extract. These extracts exhibited potential antioxidant capacity measured by peroxyl radical scavenging capacity (PSC), oxygen radical absorbance capacity (ORAC), and cellular antioxidant activity (CAA) assays. This fruit also possessed dose-dependently antiproliferative activity, and this may be due to the synergistic and additive effects of individual phenolics. Furthermore, EMW fruit showed favorable hypoglycemic activity via inhibition of activities of α-glucosidase and α-amylase, enhancement of glucose consumption, glycogen accumulation, and glycogen synthase 2 (GYS2) activity, and downregulation of activities of glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK). Therefore, EMW fruit has the potential as an ingredient of functional foods to improve human health and shows promising applications with additional health and economical benefits. PRACTICAL APPLICATION: EMW fruit is a plant-based food rich in natural phenolic compounds, which suggesting its potential bioactivities for humans such as antioxidant, antiproliferative, and hypoglycemic activities. Our findings would provide a logical strategy to promote the comprehensive utilization of phenolics in EMW fruit with both health and economical benefits.

Keywords: Ehretia macrophylla Wall. fruit; antioxidant activity; antiproliferative activity; hypoglycemic activity; phenolic profiles.