In vitro anti-diabetic activity of Tribulus terrestris L. fruits extracts

摘要

Purpose - The purpose of this paper is to evaluate the inhibition activity of Tribulus terrestris L. (T. terrestris) fruits extracts with solvents of increasing polarity against a-glucosidase and a-amylase, and to determine the inhibition mode of themost effective extract against both enzymes.Design/methodology/approach - Hexane, acetone, ethanol and aqueous extracts of T. terrestris fruits were prepared using ultrasonic sequential extraction and analyzed for their a-amylase and a-glucosidase inhibitory activities by specific assay for each enzyme. The modes of inhibitions were detected using Lineweaver-Burk plots.Findings - T. terrestris fruits extracts showed inhibition activity against a-glucosidase and a-amylase which was in the dose-dependent manner. Hexane extract had the highest a-glucosidase inhibition activity (ICso = 27.28 yug/ml, p = 0.003), followed byacetone and ethanol extracts (IC50 = 60.58 /iig/ml and IC50 = 84.21 /tig/ml, respectively). The inhibition mode of hexane extract was noncompetitive. While acetone extract showed the highest inhibition activity against a-amylase (IC50 = 6.18 mg/ml, p =0.002), hexane and ethanol extracts showed no significant difference (IC50 = 13.04mg/ml and IC50 = 14.20mg/ml, respectively,/) = 0.09). The inhibition mode of acetone extract was competitive.Originality/value - T. terrestris fruits extracts had strong inhibition activity against a-glucosidase and a-amylase, and they can be used as a promising anti-diabetic agent.