School of Food Science and Technology, School of Chemical Engineering, Hubei University of Arts and Science, Xiangyang 441053, China; Food Ingredients Engineering Technology Research Center of Hubei, Xiangyang 441053, China.
School of Energy and Intelligence Engineering, Henan University of Animal Husbandry and Economy, Zhengzhou 450002, China.
Biophys Chem. 2021 Jul;274:106592. doi: 10.1016/j.bpc.2021.106592. Epub 2021 Apr 15.
Previous studies suggested that naturally occurring EGCG primarily acted on the bacterial cell membrane then damaged the membrane and the gallate moiety in EGCG was very important to its anti-bacterial activity. However, the detailed mechanisms were still poorly understood. In this paper, EGCG and EGC were selected to study the great contribution of gallate moiety on the anti-bacterial activities of polyphenols. The results indicated that EGCG could penetrate deeper into the POPG lipid bilayer and possess more potent structure-perturbing potency on the POPG lipid bilayer than EGC. We also found that EGCG had the ability to form hydrogen bonds with the deeper inside oxygen atoms in the POPG lipid bilayer and the gallate moiety was the key functional group for EGCG forming hydrogen bonds with the POPG lipid bilayer. Moreover, results from the binding free energy analysis demonstrated that the gallate moiety made great contribution to the high affinity between EGCG and the POPG lipid bilayer. We believed that these findings could yield useful insights into the influence mechanisms of gallate moiety on the anti-bacterial activities of polyphenols.
先前的研究表明，天然存在的 EGCG 主要作用于细菌细胞膜，然后破坏细胞膜，而 EGCG 中的没食子酸酯部分对其抗菌活性非常重要。然而，其详细的作用机制仍知之甚少。在本文中，选择 EGCG 和 EGC 来研究没食子酸酯部分对多酚类化合物抗菌活性的巨大贡献。结果表明，EGCG 可以更深地渗透到 POPG 脂质双层中，并且比 EGC 更具有破坏 POPG 脂质双层的结构能力。我们还发现 EGCG 能够与 POPG 脂质双层内部更深的氧原子形成氢键，并且没食子酸酯部分是 EGCG 与 POPG 脂质双层形成氢键的关键功能基团。此外，结合自由能分析的结果表明，没食子酸酯部分对 EGCG 与 POPG 脂质双层之间的高亲和力做出了巨大贡献。我们相信这些发现可以为没食子酸酯部分对多酚类化合物抗菌活性的影响机制提供有用的见解。
