乙基麦芽酚与牛血清白蛋白相互作用的光谱  

Spectroscopic study of interaction between ethyl maltol and bovine serum albumin

作　　者：马亚娣[1] 张国文[1] 刘钰红[2] 

机构地区：[1]南昌大学食品科学与技术国家重点实验室,江西南昌330047 [2]南昌大学期刊社,江西南昌330047

出　　处：《南昌大学学报（理科版）》2011年第6期545-549,共5页Journal of Nanchang University(Natural Science)

基　　金：国家自然科学基金资助项目(31060210);国家重点实验室基金资助项目(SKLF-TS-200917;SKLF-MB-201002);江西省自然科学基金资助项目(2009GZH0069)

摘　　要：在模拟人体生理条件下,利用荧光光谱法、紫外-可见光谱法和圆二色谱法研究了乙基麦芽酚(EMA)与牛血清白蛋白(BSA)的相互作用。结果表明,EMA通过与BSA形成基态复合物使其内源荧光猝灭。利用van't Hoff方程计算出热力学参数焓变(ΔH)和熵变(ΔS)分别为116.1kJ.mol-1和481.3J.mol-1.K-1,说明疏水作用是维持EMA-BSA复合物稳定的主要作用力。位点竞争实验表明,乙基麦芽酚主要结合在BSA的亚域ⅡA上(siteⅠ位)。同步荧光光谱和圆二色谱分析显示,乙基麦芽酚的存在诱导BSA的二级结构发生变化,α-螺旋含量降低,β-折叠、β-转角和无规则卷曲的含量增加。The interaction between ethyl maltol（EMA） and bovine serum albumin（BSA） was investigated by fluorescence,UV-vis absorption and circular dichroism（CD） spectroscopy under simulative physiological conditions.The results suggested that the intrinsic fluorescence of BSA was quenched by EMA,which was probably a result of the formation of EMA-BSA complex.According to the van＇t Hoff equation,the thermodynamics parameters enthalpy change（ΔH） and entropy change（ΔS） were calculated to be 116.1 kJ·mol-1 and 481.3 J·mol-1·K-1,respectively,which indicated that hydrophobic interaction was the predominant intermolecular force in stabilizing the complex.The site marker competitive experiment revealed that the binding of EMA to BSA mainly took place in subdomain ⅡA（siteⅠ）.Synchronous fluorescence and CD spectra showed that the binding of EMA to BSA induced conformational changes in BSA with the decrease of the α-helix content of BSA.However,the content of β-sheet,β-turn and random coil increased.

关 键 词：乙基麦芽酚 牛血清白蛋白 荧光猝灭 结合位点 圆二色谱 

分 类 号：O657.3[理学—分析化学]