Flavanols from the Camellia sinensis var. assamica and their hypoglycemic and hypolipidemic activities.

ABSTRACT: ?-Glucosidase and lipase inhibitors play important roles in the treatment of hyperglycaemia and dyslipidemia. To identify novel naturally occurring inhibitors, a bioactivity-guided phytochemical research was performed on the pu-erh tea. One new flavanol, named (-)-epicatechin-3-O-(Z)-coumarate (1), and 16 known analogs (2-17) were isolated from the aqueous extract of the pu-erh tea. Their structures were determined by spectroscopic and chemical methods. Furthermore, the water extract of pu-erh tea and its fractions exhibited inhibitory activities against ?-glucosidases and lipases in vitro; compound 15 showed moderate inhibitory effect against sucrase with an IC50 value of 32.5 ?mol/L and significant inhibitory effect against maltase with an IC50 value of 1.3 ?mol/L. Compounds 8, 10, 11 and 15 displayed moderate activity against a lipase with IC50 values of 16.0, 13.6, 19.8, and 13.3 ?mol/L, respectively.

SUBMITTER: Wang X 

PROVIDER: S-EPMC5430754 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature