棉酚与其氧化物与牛血清蛋白相互作用研究.pdf

现代食品科技 Modern Food Science and Technology 2015, Vol.31, No.6 棉酚及其氧化物与牛血清蛋白相互作用的研究 柴秀航，毕艳兰，彭丹，王亚 （河南工业大学粮油食品学院，河南郑州450001 ） 摘要：利用紫外-可见吸收光谱和荧光光谱法研究棉酚及其氧化物与牛血清蛋白（bovine serum albumin, BSA ）的结合作用。实 验结果表明，棉酚及其氧化物与牛血清蛋白相互作用而引起的荧光猝灭机制均属于动态和静态的联合猝灭，BSA 发射峰蓝移。通过 5 计算各个结合参数得出：棉酚及其氧化物与BSA 的结合常数在10 数量级，说明棉酚及其氧化物与BSA 有很强的结合，结合位点均 为1；热力学参数ΔH0、ΔS0 和ΔG0，表明棉酚及其氧化物与BSA 结合的主要作用力为疏水作用力和氢键。根据Forster 的非辐 射能量转移理论，计算供体(BSA)与受体（棉酚及其氧化物）间的结合距离r 分别为2.94 nm 和3.12 nm，它们都能以能量转移的方式 与BSA 发生作用。紫外-可见光谱、同步荧光光谱和三维荧光光谱的研究结果表明，棉酚及其氧化物与BSA 的结合引起了BSA 的构 象变化。 关键词：棉酚；棉酚氧化物；牛血清蛋白；荧光光谱；同步荧光光谱 文章篇号：1673-9078(2015)6-36-43 DOI: 10.13982/j.mfst.1673-9078.2015.6.007 Interaction of Gossypol and Its Oxide with Bovine Serum Albumin CHAI Xiu-hang, BI Yan-lan, PENG Dan, WANG Ya (School of Food Science and Technology, Henan University of Technology, Zhengzhou 450001, China) Abstract: The interaction of gossypol and its oxide with bovine serum albumin (BSA) was investigated by fluorescence spectroscopy and ultraviolet-visible spectroscopy (UV-vis). The experimental results indicated that the quenching mechanism of BSA by gossypol and its oxide was a combined dynamic and static quenching, with a blue-shift of the emission maximum of BSA. The calculation of various binding 5 parameters showed that the binding constants for gossypol-BSA and gossypol oxide-BSA were in the order of 10 , indicating a strong interaction between gossypol/gossypol oxide and BSA. There was one binding site involved in the interaction between gossypol/gossypol oxide and BSA. The negative value o