荧光猝灭法研究二氢槲皮素和二氢杨梅素与牛血清白蛋白的相互作用

An interaction study of bovine serum albumin with dihydroquercetin and dihydromyricetin by fluorescence quenching method

目的研究二氢槲皮素和二氢杨梅素与牛血清白蛋白(BSA)的相互作用。方法运用荧光光谱法结合Stern-Volmer方程和Line Weaver-Burk双倒数函数计算出BSA与二氢槲皮素和二氢杨梅素相互作用的猝灭常数和结合常数,通过反应前后热力学参数如焓变ΔH和熵变ΔS的大小对作用力类别进行判断。结果测得二氢槲皮素与BSA在不同温度下的结合常数293K为2.27×10~4L·mol^(-1),298 K为2.06×10~4L·mol^(-1),303 K为1.89×10~4L·mol^(-1),二氢杨梅素与BSA在不同温度下的结合常数293 K为2.43×10~4L·mol^(-1),298 K为2.39×10~4L·mol^(-1),303 K为2.13×10~4L·mol^(-1)。确定其使牛血清白蛋白荧光猝灭的过程为静态猝灭过程,通过热力学参数确定其结合力主要为疏水作用。结论应用荧光猝灭法了解二氢槲皮素和二氢杨梅素与牛血清白蛋白之间有较强的结合反应,结合力以疏水作用力为主。

Objective To study the interaction of bovine serum albumin（ BSA） with dihydroquercetin and dihydromyricetin. Methods The quenching constants and binding constants of the interaction of BSA with dihydroquercetin and dihydromyricetin were calculated by fluorescent spectrometry together with Stern-Volmer equation and Lineweaver-Burk double reciprocal plot. Applied forces were judged by the values of thermodynamics parameters such as enthalpy change（ ΔH） and entropy change（ ΔS） before and after the bonding. Results The binding constants of BSA with dihydroquercetin at different temperatures were 2. 27 × 10^4 L·mol^-1 at 293 K,2. 06 × 10^4 L·mol^-1 at 298 K,and 1. 89 × 10^4 L·mol^-1 at 303 K,respectively. The binding constants of BSA with dihydromyricetin at different temperatures were 2. 43 × 10^4 L·mol^-1 at 293 K,2. 39 × 10^4 L· mol^-1 at 298 K,and 2. 13 × 10^4 L· mol^-1 at303 K,respectively. The quenching mechanism of them was showed as static quenching and the binding force was mainly hydrophobic force. Conclusion The binding reactions of BSA with dihydroquercetin and dihydromyricetin were fairly strong,and the binding force was mainly hydrophobic.