Gao Yunlong, Focsan A Ligia, Kispert Lowell D
College of Sciences, Nanjing Agricultural University, Nanjing 210095, China.
Department of Chemistry, Valdosta State University, Valdosta, GA 31698, USA.
Antioxidants (Basel). 2020 Jul 16;9(7):625. doi: 10.3390/antiox9070625.
Carotenoids are well-known antioxidants. They have the ability to quench singlet oxygen and scavenge toxic free radicals preventing or reducing damage to living cells. We have found that carotenoids exhibit scavenging ability towards free radicals that increases nearly exponentially with increasing the carotenoid oxidation potential. With the oxidation potential being an important parameter in predicting antioxidant activity, we focus here on the different factors affecting it. This paper examines how the chain length and donor/acceptor substituents of carotenoids affect their oxidation potentials but, most importantly, presents the recent progress on the effect of polarity of the environment and orientation of the carotenoids on the oxidation potential in supramolecular complexes. The oxidation potential of a carotenoid in a nonpolar environment was found to be higher than in a polar environment. Moreover, in order to increase the photostability of the carotenoids in supramolecular complexes, a nonpolar environment is desired and the formation of hydrogen bonds should be avoided.
类胡萝卜素是众所周知的抗氧化剂。它们具有淬灭单线态氧和清除有毒自由基的能力，可防止或减少对活细胞的损伤。我们发现类胡萝卜素对自由基具有清除能力，这种能力随着类胡萝卜素氧化电位的增加几乎呈指数增长。由于氧化电位是预测抗氧化活性的一个重要参数，我们在此关注影响它的不同因素。本文研究了类胡萝卜素的链长和供体/受体取代基如何影响其氧化电位，但最重要的是，介绍了关于超分子复合物中环境极性和类胡萝卜素取向对氧化电位影响的最新进展。发现类胡萝卜素在非极性环境中的氧化电位高于在极性环境中的氧化电位。此外，为了提高类胡萝卜素在超分子复合物中的光稳定性，需要非极性环境，并且应避免形成氢键。
