The inhibitory effects of delphinidin-3-O-galactoside (DG) on the activities of tyrosinase (EC 1.14.18.1) (TY) from the edible Agaricus bisporus mushroom were investigated by enzyme kinetics, multispectroscopic methods, and molecular docking. As a result, DG showed strong inhibition on TY with the IC₅₀ of 34.14 × 10^–6 mol L^–1. The inhibition mode of DG against TY was mixed type with α values of 5.09. The binding constant K_a and related thermodynamic parameters at the three different temperatures showed that the fluorescence quenching of TY by DG was static quenching. Synchronous fluorescence, three-dimensional fluorescence, ultraviolet–visible spectroscopy, and circular dichroism spectroscopies confirmed that the conformation or microenvironment of the TY protein were changed after binding with DG. Molecular docking revealed that DG had strong binding affinity to TY through hydrogen bonding and van der Waals force, and the results were consistent with the fluorescence data. Our findings suggested that DG may be potential TY inhibitor.

中文翻译：

---

飞燕草素-3-O-半乳糖苷与酪氨酸酶相互作用的光谱研究及分子对接

通过酶动力学、多光谱方法和分子对接研究了飞燕草素-3-O-半乳糖苷（DG）对食用双孢蘑菇酪氨酸酶（EC 1.14.18.1）（TY）活性的抑制作用。结果，DG对TY表现出很强的抑制作用，IC ₅₀为34.14 × 10 ^–6  mol L ^–1。DG对TY的抑制方式为混合型，α值为5.09。结合常数K _a以及三个不同温度下的相关热力学参数表明，DG对TY的荧光猝灭是静态猝灭。同步荧光、三维荧光、紫外-可见光谱和圆二色光谱证实TY蛋白与DG结合后构象或微环境发生改变。分子对接表明DG通过氢键和范德华力与TY具有很强的结合亲和力，结果与荧光数据一致。我们的研究结果表明，DG 可能是潜在的 TY 抑制剂。