Curcumin as a mild natural α‐glucosidase inhibitor: a study on its mechanism <i>in vitro</i>
Yujia Liu, Jie Zhu, Jiamei Yu, Xu Chen, Shuyan Zhang, Yanxue Cai, Lin Li
Abstract
Summary Curcumin, natural dietary ingredient, is considered as mild effective inhibitors for α‐glucosidase to prevent type 2 diabetes. In this work, spectroscopic techniques combined with molecular simulation were used to further understand the inhibition kinetic mechanism of curcumin on α‐glucosidase. Curcumin showed a mild inhibition effect (IC 50 =20.54 ± 1.02 mg/ml) for α‐glucosidases through a competitive inhibition mechanism, and it led to fluorescence quenching as well as energy transfer by binding behaviour (average binding distance, r 0 = 2.43 nm). Hydrogen bonds and steric hindrance were the main interactions between curcumin and the activity site of α‐glucosidases, as revealed by molecular docking. Circular dichroism spectroscopy results also indicate that curcumin affected the denaturation temperature of α‐glucosidases, which dropped from 74 °C to 68 °C, resulting in inhibition. The findings can contribute to a better understanding of the development and application of curcumin in functional dietary food.