Department of Pharmacognosy and Chemistry of Natural Products, School of Pharmacy, University of Athens , Panepistimiopolis, Zografou, 15771 Athens, Greece.
J Agric Food Chem. 2011 Jun 22;59(12):6412-22. doi: 10.1021/jf2011535. Epub 2011 May 25.
The antibacterial and antifungal activities of an ample number of phenolic compounds isolated from Quercus ilex leaves, belonging to the classes of flavonoids, proanthocyanidins, and phenolic acids, are discussed. The isolation of A type proanthocyanidin, (+)-epigallocatechin-(2β→O→7, 4β→8)-(+)-catechin is reported for the first time. Its structure was established by means of highfield NMR (correlation spectroscopy, heteronuclear single quantum correlation, heteronuclear multiple bond correlation, and rotating frame Overhauser effect spectroscopy) and MS spectral analyses, while its absolute configuration was determined by circular dichroism measurements. The isolated compounds were tested for their antimicrobial effects against eight human bacterial species and 14 fungal species. In a second step, the most potent compounds were tested in combination with the conventional fungicides, bifonazole and ketoconazole, to evaluate possible synergistic effects. Results showed that proanthocyanidins 3 and 4 when combined with bifonazole and ketoconazole increase the activity of both of these conventional fungicides. Moreover, the pharmacokinetic profile of the isolated compounds was investigated using computational methods.
本文讨论了从属于类黄酮、原花青素和酚酸的栎树叶中分离得到的大量酚类化合物的抗菌和抗真菌活性。首次报道了 A 型原花青素（+）-表没食子儿茶素-(2β→O→7, 4β→8)-(+)-儿茶素的分离。其结构通过高场 NMR（相关光谱、异核单量子相关、异核多键相关和旋转框架 Overhauser 效应光谱）和 MS 光谱分析确定，而其绝对构型则通过圆二色性测量确定。对分离得到的化合物进行了抗菌试验，测试了它们对 8 种人体细菌和 14 种真菌的抗菌效果。在第二步中，对最有效的化合物进行了与常规抗真菌药联苯苄唑和酮康唑的联合测试，以评估可能的协同作用。结果表明，原花青素 3 和 4 与联苯苄唑和酮康唑联合使用时，会增加这两种常规抗真菌药的活性。此外，还使用计算方法研究了分离化合物的药代动力学特征。
