School of Chemical Engineering, Sichuan Uiversity, Chengdu 610065, China.
School of Chemical Engineering, Sichuan Uiversity, Chengdu 610065, China.
Food Chem. 2018 Mar 15;243:74-81. doi: 10.1016/j.foodchem.2017.09.109. Epub 2017 Sep 21.
Considering the adverse effect of food additives on humans, thorough research of their physiological effects at the molecular level is important. The interactions of cinnamaldehyde (CNMA), a food perfume, and its major metabolite cinnamic acid (CA) with human serum albumin (HSA) were examined by multiple-spectroscopies. NMR analysis revealed CNMA and CA both bound to HSA, and STD-NMR experiments established CNMA and CA primarily interacted with site I and site II of HSA, respectively. The ligands caused strong quenching of HSA fluorescence through a static quenching mechanism, with hydrophobic and electrostatic interaction between CNMA/CA and HSA, respectively. UV-vis absorption and CD results showed ligands induced secondary structure changes of HSA. Binding configurations were proved by docking method. Furthermore, binding constants of CNMA/CA-HSA systems were influenced by the addition of four other food additives. These studies have increased our knowledge regarding the safety and biological action of CNMA and CA.
考虑到食品添加剂对人类的不良影响，深入研究其在分子水平上的生理效应非常重要。本研究采用多种光谱法研究了食用香料肉桂醛（CNMA）及其主要代谢产物肉桂酸（CA）与人血清白蛋白（HSA）的相互作用。NMR 分析表明，CNMA 和 CA 均与 HSA 结合，通过 STD-NMR 实验确定 CNMA 和 CA 分别主要与 HSA 的 I 型和 II 型结合位点相互作用。配体通过静态猝灭机制强烈猝灭 HSA 荧光，CNMA/CA 与 HSA 之间分别存在疏水相互作用和静电相互作用。紫外-可见吸收和 CD 结果表明配体诱导 HSA 的二级结构发生变化。通过对接方法证明了结合构象。此外，四种其他食品添加剂的加入影响了 CNMA/CA-HSA 体系的结合常数。这些研究增加了我们对 CNMA 和 CA 的安全性和生物作用的认识。
