Inhibitory Effects against Alpha-Amylase of an Enriched Polyphenol Extract from Pericarp of Mangosteen (Garcinia mangostana)

The pericarp of mangosteen, a by-product of the mangosteen, is rich in polyphenols. In this study, an efficient and environmentally friendly method for preparative enrichment of polyphenols from mangosteen pericarp (MPPs) was developed, and the inhibitory effects on starch digestion were also evaluated. It was found that the optimal extract method of MPPs was at a solid to solvent ratio of 1:50 g/mL, pH of 2, and at 80 degrees C for 2 h. The IC50 of MPPs for alpha-amylase was 0.28 mg/mL. Based on the fluorescence quenching results, we presumed that MPPs could alter the natural structure of alpha-amylase, resulting in inhibitory activity on alpha-amylase. In addition, MPPs significantly reduced the blood glucose peak and AUC of glucose responses in rats after ingestion of the starch solution. Taken together, MPPs may have the potential as a functional supplement for blood glucose control and diabetes prevention.

Automated summary

In this study, an efficient method for enriching polyphenols from mangosteen pericarp (MPPs) was developed, and its inhibitory effects on starch digestion were evaluated. The results showed that MPPs had inhibitory activity on alpha-amylase and could reduce blood glucose peak and glucose response AUC.