Itoh S, Nagaoka S, Mukai K, Ikesu S, Kaneko Y
Department of Chemistry, Faculty of Science, Ehime University, Matsuyama, Japan.
Lipids. 1994 Nov;29(11):799-802. doi: 10.1007/BF02536703.
Quenching reactions of singlet oxygen and scavenging reactions of free radicals by alpha-, beta-, gamma- and delta-tocopheramines (Toc-amines) were investigated spectrophotometrically in ethanol and Triton X-100 micellar dispersions. The rate constants of quenching of singlet oxygen (kQ) by alpha-, beta-, gamma- and delta-Toc-amines increased as the total electron donating capacity of the methyl groups at the aromatic ring increased. A plot of logkQ vs. peak oxidation potential (Ep) was found to be linear and the slope was negative. Similar results were obtained for scavenging of a phenoxyl radical (PhO.). The results suggest that charge transfer plays an important role in these reactions. The kQ values were found to be 1.30-2.57 times as large as kQ for alpha-tocopherol (alpha-Toc). Although alpha-Toc has the highest antioxidant activity among natural tocopherols and related phenols, Toc-amines also can serve as antioxidants.
在乙醇和Triton X - 100胶束分散体系中，采用分光光度法研究了α-、β-、γ-和δ-生育胺（生育胺）对单线态氧的猝灭反应以及对自由基的清除反应。随着芳香环上甲基总给电子能力的增加，α-、β-、γ-和δ-生育胺对单线态氧的猝灭速率常数（kQ）增大。发现logkQ对峰值氧化电位（Ep）的作图呈线性，且斜率为负。对于苯氧基自由基（PhO·）的清除也得到了类似结果。结果表明电荷转移在这些反应中起重要作用。发现kQ值是α-生育酚（α-Toc）kQ值的1.30 - 2.57倍。尽管α-Toc在天然生育酚和相关酚类中具有最高的抗氧化活性，但生育胺也可作为抗氧化剂。
