Department of Genetics, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa, Poland.
Food Chem. 2013 Nov 15;141(2):1227-41. doi: 10.1016/j.foodchem.2013.04.018. Epub 2013 Apr 17.
Plant polyphenols, such as flavonoids, are ubiquitous components of human diet, and have been recognised as efficient radical scavengers and antioxidants. Their protective effects were especially seen in cell-free assays. Whilst in living cells, depending on experimental conditions, polyphenols may manifest both anti- and pro-oxidative activity. In the present study, the effectiveness of fifteen structurally different flavonoids against hypochlorite-mediated changes in in vitro systems, with and without cells, was tested and compared. Quercetin was found to be the best protector against hypochlorite-mediated fluorescein bleaching and BSA thiol groups oxidation, whilst in living cells its effects on hypochlorite-associated cytotoxicity were moderate. Contrary, epigallocatechin gallate, pelargonidin and catechin, with less impressive hypochlorite scavenging activity in cell-free assays, were the most effective against 3-chlorotyrosine formation after hypochlorite treatment. Taken together, special care should be taken when extrapolating the results on antioxidant propensity of food bioactive compounds in vitro to the cellular milieu.
植物多酚，如类黄酮，是人类饮食中无处不在的成分，已被认为是有效的自由基清除剂和抗氧化剂。它们的保护作用在无细胞检测中尤为明显。然而，在活细胞中，根据实验条件的不同，多酚可能表现出抗氧化和促氧化活性。在本研究中，测试并比较了 15 种结构不同的类黄酮对体外体系中次氯酸盐介导的变化的有效性，包括有无细胞的情况。研究发现，槲皮素是防止次氯酸盐介导的荧光素漂白和 BSA 巯基氧化的最佳保护剂，而在活细胞中，其对次氯酸盐相关细胞毒性的影响则较为温和。相反，表没食子儿茶素没食子酸酯、锦葵色素和儿茶素在无细胞检测中对次氯酸盐的清除活性较低，但在次氯酸盐处理后，对 3-氯酪氨酸的形成具有最强的抑制作用。综上所述，当将体外食物生物活性化合物的抗氧化倾向的结果推断到细胞环境时，应特别注意。
