ABSTRACT
Objective Taking 41 kinds of Chinese herbal medicines commonly used in Meizhou Hakka as the research object,their inhibitory activities against α-glucosidase and α-amylase were screened and the enzyme inhibition types of the species with the strongest activities were explored.Methods The inhibitory activities of 41 commonly used Hakka herbs in Meizhou against α-glucosidase and α-amylase were evaluated by the p-Nitrophenyl a-D-mannopyranoside(pNPG)method and the 3,5-Dinitrosalicylic acid(DNS)method,using the inhibitory rate of half(IC50)as an index.The inhibitory activity of 95%ethanol extracts of 41 Chinese herbal medicines commonly used in Meizhou Hakka on α-glucosidase and α-amylase were analysed.The enzymatic kinetics method and Lineweaver-Burk curve were used to analyze the inhibitory type of the most active species.Results The results showed that 40 Chinese herbal medicines commonly used in Meizhou Hakka had α-glucosidase inhibitory activity,and 23 medicines had α-amylase inhibitory activity,among which Psychotria asiatica Wall.showed the strongest inhibitory activity with the IC50 values aganist α-glucosidase and α-amylase of 0.17±0.001 mg·mL-1 and 0.09±0.001 mg·mL-1,respectively.The inhibition types were reversible competitive inhibition and reversible non-competitive inhibition,respectively.Conclusion The Psychotria asiatica Wall.Chinese herbal medicines commonly used in Meizhou Hakka has significant inhibitory effect on the activity of glucose metabolism enzymes,which has potential value for further research and development on the prevention and treatment of diabetes mellitus.