Phenolic compounds profile of Amomum tsaoko Crevost et Lemaire and their antioxidant and hypoglycemic potential

This study determined the phytochemical composition and bioactivity (antioxidant and hypoglycemic) in five fractions (petroleum ether, chloroform, ethyl acetate, n-butanol, and water fractions) obtained from ethanol extract of Amomum tsaoko Crevost et Lemaire (A. tsaoko). Qualitative and quantitative analyses of phenolic compounds were carried out with UHPLC-ESI-QTOF-MS/MS. 50 bioactive compounds were identified from five different fractions, including 11 phenolic acids and derivatives, 18 flavonoids and derivatives, 14 proanthocyanidins, 2 organic acids, and 5 other compounds. It was found that ethyl acetate fraction (EF) was enriched with the most types and contents of substances. Flavonoids and derivatives (including epicatechin and catechin) were the primary phenolic compounds in EF. In addition, EF demonstrated excellent antioxidant activity (DPPH and ABTS with IC50 = 0.17 and 0.07 mg/mL, FRAP of 546.10 mg VCE/g DW) and anti-α-glucosidase activity (IC50 = 20.14 μg/mL). EF could ameliorate fasting blood glucose and glucose tolerance of diabetic mice. In conclusion, EF could be developed as a potential candidate for preventing or treating oxidative stress diseases and diabetes.