Kinetic Study of the Scavenging Reaction of the Aroxyl Radical by Eight Kinds of Vegetable Oils in Solution
Kinetic Study of the Scavenging Reaction of the Aroxyl Radical by Eight Kinds of Vegetable Oils in Solution
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DOI：
10.1002/aocs.12076
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发表时间：
2018-06
期刊：
影响因子：
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通讯作者：
K. Mukai;Y. Bandoh;Junya Ito;Eri Kobayashi;K. Nakagawa;S. Nagaoka
中科院分区：
文献类型：
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作者：
K. Mukai;Y. Bandoh;Junya Ito;Eri Kobayashi;K. Nakagawa;S. Nagaoka
本文对aroxl自由基（ArO•）与含有不同浓度α‐、β‐、γ‐和δ‐生育酚和生育三烯醇（- Tocs和- Toc‐3s）的8种植物油（1-8）的反应进行了详细的动力学研究。在乙醇/氯甲烷/D2O （50:50:1, v/v/v）溶液中，用停流分光光度法测定了ArO•与植物油（米糠1、紫苏2、菜籽3、红花4、葡萄籽5、芝麻6、特级初榨橄榄7和橄榄油8）反应的二阶速率常数（ks）和ARAC （ARAC）值。活性最高的米糠油1的ksvalue （16.1 × 10−3L g−1s−1）是活性最低的橄榄油8的ksvalue （2.02 × 10−3）的8.0倍。采用高效液相色谱-质谱/质谱法（HPLC - MS/MS）测定了植物油1 - 8中α‐、β‐、γ‐、δ‐Tocs和‐Toc‐3s的浓度（单位为mg 100 g−1）。从这些结果可以清楚地解释，植物油1-8的ArO•‐清除率（ks）（即相对ARAC值）可以很好地解释为速率常数（）与植物油中含有的AOH‐i（Tocs和Toc‐3s）的浓度（[AOH‐i]/105）的乘积之和。结果表明，ARAC法可用于评价一般食品提取物的抗氧化活性。
A detailed kinetic study was performed for the reaction of the aroxyl radical (ArO•) with eight vegetable oils 1–8, which contain different concentrations of α‐, β‐, γ‐, and δ‐tocopherols and ‐tocotrienols (‐Tocs and ‐Toc‐3s). The second‐order rate constants (ks) and aroxyl radical absorption capacity (ARAC) values for the reaction of ArO• with vegetable oils 1–8 (rice bran 1, perilla 2, rapeseed 3, safflower 4, grape seed 5, sesame 6, extra virgin olive 7, and olive oils 8) were measured in ethanol/chloroform/D2O (50:50:1, v/v/v) solution at 25 °C using stopped‐flow spectrophotometry. Theksvalue (16.1 × 10−3L g−1s−1) of rice bran oil 1 with the highest activity was 8.0 times larger than that (2.02 × 10−3) of olive oil 8 with the lowest activity. The concentrations (in mg 100 g−1) of α‐, β‐, γ‐, and δ‐Tocs and ‐Toc‐3s contained in the vegetable oils 1–8 were determined using high performance liquid chromatography‐mass spectrometry/mass spectrometry (HPLC‐MS/MS). From these results, it was clarified that the ArO•‐scavenging rates (ks) (i.e., the relative ARAC value) obtained for the vegetable oils 1–8 may be well explained as the sum of the product of the rate constant () and the concentration ([AOH‐i]/105) of AOH‐i(Tocs and Toc‐3s) included in vegetable oils. The results suggest that the ARAC assay method might be used in the evaluation of antioxidant activity of general food extracts.