Department of Viticulture and Enology, University of California, Davis, California 95616, USA.
J Agric Food Chem. 2011 Jun 8;59(11):6221-6. doi: 10.1021/jf200115y. Epub 2011 May 11.
Plant-derived polyphenolic compounds have received much attention for their ability to sequester high-energy free radicals in a great variety of food-related and biological systems, protecting those systems from oxidative change. The ability of these compounds to scavenge free radicals has always been attributed to their phenolic functionality, from which a hydrogen atom can be easily abstracted. In this study, the cinnamates and the ubiquitous hydroxycinnamates were found to equally suppress the formation of oxidation products in wine exposed to the Fenton reaction (catalytic Fe(II) with hydrogen peroxide). Mechanistic investigations led to the unexpected discovery that the α,β-unsaturated side chain of cinnamic acids could efficiently trap 1-hydroxyethyl radicals, representing a newly discovered mode of antioxidant radical scavenging activity for these broadly occurring compounds in a food system. The proposed pathway is supported by prior fundamental studies with radiolytically generated radicals.
植物源多酚化合物因其在各种与食品相关和生物系统中螯合高能自由基的能力而受到广泛关注，从而保护这些系统免受氧化变化。这些化合物清除自由基的能力一直归因于其酚官能团，其中氢原子很容易被提取。在这项研究中，发现肉桂酸酯和无处不在的羟基肉桂酸酯在芬顿反应（催化 Fe(II)与过氧化氢）中同样能抑制葡萄酒中氧化产物的形成。机理研究导致了一个意外的发现，肉桂酸的α,β-不饱和侧链可以有效地捕获 1-羟乙基自由基，这代表了这些在食品系统中广泛存在的化合物的一种新发现的抗氧化自由基清除活性模式。所提出的途径得到了先前用辐射生成自由基进行的基础研究的支持。
