荧光光谱法研究木栓酮与牛血清白蛋白的相互作用

为了解三萜类化合物在体内的结合转运机制,采用荧光光谱法结合紫外吸收光谱研究从中药爵床中分离的有效成分木栓酮(Friedelin,FDL)与牛血清白蛋白(Bovine serum albumin,BSA)的结合反应.通过研究木栓酮对牛血清白蛋白内源性荧光的淬灭作用,发现木栓酮可以与牛血清白蛋白相互结合,且其作用是一个静态猝灭的过程.通过计算木栓酮与牛血清白蛋白的结合常数和结合位点,发现在生理弱碱性溶液中二者具有较强的结合作用,且以1:1结合.根据热力学参数推测木栓酮与牛血清白蛋白的作用力类型为氢键和范德华力.根据F rster非辐射能量转移机理,计算出木栓酮与牛血清白蛋白结合距离为2.86 nm.研究表明木栓酮在体内可以通过血清白蛋白进行结合和转运.

Spectroscopic Studies on Interaction of Friedelin with Bovine Serum Albumin

In order to find the transport mechanism of triterpenoids in vivo,the fluorescence and UV-Vis spectroscopic methods were used to study the binding reaction between friedelin,a pentacyclic triterpenoid isolated from Rostellularia procumbens,and bovine serum albumin(BSA).The fluorescent emission of BSA was inhibited by friedelin in a dosedependent manner,indicating that friedelin interacted with BSA by a static process.The binding constant and the number of binding sites were calculated based on the quenching effect of freidelin on BSA,and the results indicated that friedelin interacted with BSA in high affinity with the binding ratio of 1 : 1 under alkalescent condition.Thermodynamic parameter study indicated the interaction force between friedelin and BSA was hydrogen bonding and van der Waals force.The distance between friedelin and BSA was calculated to be 2.86 nm according to F rster non-radiative energy transfer theory.These results demonstrate that friedelin could bind with serum albumin.