红花忍冬黄酮类成分与牛血清白蛋白的相互作用

Interaction of flavonoids in Lonicera syringantha Maxim.with bovine serum albumin

目的:研究红花忍冬黄酮类成分与牛血清白蛋白(BSA)结合作用的机制。方法:采用荧光猝灭法和紫外吸收光谱法计算黄酮类分子与BSA的结合常数和结合距离,并根据热力学参数确定它们之间的主要作用力类型。结果:红花忍冬黄酮类小分子能够插入BSA内部与BSA形成复合物,导致BSA内源性荧光猝灭,黄酮分子中羟基对内源性荧光猝灭有一定的影响,猝灭机理主要为静态猝灭和非辐射能量转移。结合过程的热力学参数变化表明上述过程是一个熵增的自发分子间作用过程。结论:BSA与红花忍冬黄酮类小分子间有较强的结合作用,且结合以疏水作用为主,同时还存在偶极-偶极作用。

Aim：To study the interaction of flavonoids with bovine serum albumin（BSA）. Methods：Spectrophotometry and fluorescence quenching method were employed to characterize the possible interaction between flavonoids and BSA. The binding constant and distance between flavonoids and BSA were calculated, and the main type of binding force was determined based on thermodynamic parameters. Results： Flavonoids could insert into the hydrophobic pockets of BSA, thereby quenching the inner fluorescence of BSA by forming the flavonoids-BSA complex. Both static quenching and nonradiative energy transferring were confirmed to result in the fluorescence quenching. It was also found that the hydroxide radical of the molecular structures affected the quenching efficiency. The binding process of flavonoid molecule with BSA was a spontaneous molecular interaction procedure in which entropy increased. Conclusions：There exists a relatively strong binding force between flavonoids and BSA, due to hydrophobic force as well as dipole-dipole force.