Abstract
In this study, successive extractions of the Pu-erh tea were performed utilising water, chloroform, ethyl acetate, and n-butanol. The different extracts were investigated for regulation of transcription factors involved in lipid metabolism including Farnesoid X Receptor (FXR), Liver X-activated Receptor (LXR), and the Peroxisome Proliferator-Activated Receptor (PPARγ and PPARδ) using reporter gene assays. The data indicated that the ethyl acetate extract had the strongest activation potential for FXR and PPARδ, and Fraction 6 from the ethyl acetate extract obtained by column chromatography had the highest hypolipidaemic potential. Further chromatographic separation of Fraction 6 led to the isolation of 7 flavonoids, and their contents varied between 7.6 and 51.8 mg/g. Additionally, sixty-four chemical constituents were identified from Fraction 6 by UPLC-MS/MS and their relative amounts were determined by the ion intensity. These results showed that the flavonoids were the major bioactive compounds in Pu-erh tea responsible for its hypolipidaemic effects.