A new functionality study of vanillin as the inhibitor for α-glucosidase and its inhibition kinetic mechanism.

Vanillin is a natural phenolic compound mainly used as flavors in food industry. In this work, a new functionality of vanillin as the α-glucosidase inhibitor was studied based on the inhibition kinetic mechanism. The inhibitory effect (IC50) of vanillin against α-glucosidase was 28.34 ± 0.89 mg/mL, which belongs to mixed inhibition mechanism and its process was spontaneous. Vanillin could bind to α-glucosidase by hydrophobic interactions and hydrogen bonds with -8.42 kcal/mol intermolecular energy to form the steric hindrance. The average binding distances was calculated as 2.20 nm according to energy transfer theory. In addition, the protein secondary structure and denaturation temperature (decreasing about 10 °C) were changed significantly after vanillin binding to α-glucosidase, resulting in an inhibitory effect. The findings of this research provide insights for the development of vanillin as potential inhibitor for α-glucosidase in special dietary foods.