Inhibition Mechanism of Berberine on α‐Amylase and α‐Glucosidase in Vitro

Abstract Berberine is separated from medical plants and food raw materials, and shows excellent anti‐diabetic activity and could be used as a food additive in some countries and regions. However, its inhibitory mechanisms on α‐amylase and α‐glucosidase have hardly ever been revealed in vitro. In this study, enzymatic reaction kinetics, fluorescence quenching, circular dichroism spectroscopy, and molecular docking are used to study the inhibitory effects of berberine on α‐amylase and α‐glucosidase. Berberine has great inhibitory effects on α‐amylase and α‐glucosidase (IC 50 = 50.83 µg mL –1 , IC 50 = 198.4 µg mL –1 , respectively), and inhibition types of α‐amylase and α‐glucosidase are non‐competitive inhibition and competitive inhibition, respectively. Fluorescence spectra show that there is static quenching between berberine and α‐amylase or α‐glucosidase. Besides, hydrophobic interaction is the main interaction type. These results are further evidenced and visualized by molecular docking. This study provides a different theoretical basis for berberine in anti‐diabetic activity in vitro and expands interaction research about hydrophobic compounds and α‐amylase as well as α‐glucosidase.