Inhibition of oxidation of methyl linoleate in solution by vitamin E and vitamin C.

作者：Etsuo Niki, Tadatoshi Saito, Akira Kawakami, Yoshio Kamiya · 发表于：Journal of Biological Chemistry · 年份：1984 · DOI：10.1016/s0021-9258(17)43026-2 · 被引用次数：582 · 研究领域：Vitamin C and Antioxidants Research、Antioxidant Activity and Oxidative Stress、Vitamin K Research Studies

The oxidation of methyl linoleate in solution initiated with azo compounds has been studied in the absence and presence of vitamin E and vitamin C. Both vitamin E and vitamin C acted as a chain-breaking antioxidant and they suppressed the oxidation and produced an induction period. The inhibition rate constant for the scavenging of peroxy radical was calculated at 37 degrees C as kinh = 5.1 X 10(5) M-1 s-1 and 7.5 X 10(4) M-1 s-1 for vitamin E and vitamin C, respectively. It was suggested that each vitamin E could trap two peroxy radicals, whereas vitamin C could trap only one peroxy radical under the reaction conditions employed in this study. When both vitamin E and vitamin C were present, the oxidation was suppressed quite efficiently and the apparent inhibition rate constant was obtained as kinh = 4.0 X 10(5) M-1 s-1. Furthermore, vitamin E remained almost unchanged and only vitamin C was consumed at the initial stage and vitamin E was consumed after vitamin C was exhausted. It was concluded that vitamin E trapped the peroxy radical and the resulting alpha-chromanoxy radical reacted with vitamin C to regenerate vitamin E.