State Key Laboratory of Food Science and Technology, Nanchang University, 235 Nanjing East Road, Nanchang 330047, China.
Food Funct. 2017 Jul 19;8(7):2601-2610. doi: 10.1039/c7fo00236j.
Dihydromyricetin (DMY), a natural flavonoid, was found to effectively inhibit tyrosinase activity in a mixed-type manner with an IC value of (3.66 ± 0.14) × 10 mol L. DMY combined with the dietary vitamin D at lower concentrations exhibited a synergistic effect on the inhibition of tyrosinase. The formation of a DMY-tyrosinase complex led to fluorescence quenching and conformational changes of tyrosinase, which was driven mainly by hydrophobic interactions and hydrogen bonds. The molecular simulation further found that DMY inserted into the active pocket of tyrosinase interacted with amino acid residues Tyr78, His85, and Ala323, occupying the catalytic center of tyrosinase to hinder entrance of the substrate, leading to the inhibition of tyrosinase. This study may provide a scientific foundation for screening effective tyrosinase inhibitors.
二氢杨梅素（DMY）是一种天然黄酮类化合物，被发现以混合方式有效抑制酪氨酸酶活性，IC 值为（3.66±0.14）×10-5mol/L。DMY 与较低浓度的膳食维生素 D 结合表现出对酪氨酸酶抑制的协同作用。DMY-酪氨酸酶复合物的形成导致荧光猝灭和酪氨酸酶构象变化，这主要是由疏水相互作用和氢键驱动的。分子模拟进一步发现，DMY 插入酪氨酸酶的活性口袋中，与 Tyr78、His85 和 Ala323 氨基酸残基相互作用，占据酪氨酸酶的催化中心，阻碍底物进入，从而抑制酪氨酸酶。本研究可为筛选有效酪氨酸酶抑制剂提供科学依据。
