Lehmann J, Slover H T
Lipids. 1976 Dec;11(12):853-7. doi: 10.1007/BF02532992.
The relative stabilities of selected individual tocols and tocotrienols and of equimolar mixtures of either alpha- plus gamma- or alpha- plus delta- tocopherols were determined in methyl myristate and methyl linoleate during autoxidation and photolysis. Solutions containing 0.05% of the appropriate tocopherol(s) or tocotrienols were subjected to UV light (254 nm) or to a flow of 4.3 ml/min of oxygen, both at 70 C. Tocopherols (T) and tocotrienols (T-3) were determined by gas chromatography without preliminary separation or purification. Under photolytic conditions, stabilities in increasing order in methyl myristate were gamma-T-3 less than alpha-T-3 less than delta-T less than alpha-T less than gamma-T less than 5,7-T less than beta-T and in methyl linoleate were alpha-T less than alpha-T-3 less than or equal to gamma-T-3 less than or equal to beta-T less than or equal to 5,7-T less than gamma-T less than delta-T. A solvent effect on the initial rate of photolysis was observed for 5-methyl substituted tocols but not for the tocols with an unsubstituted 5-position or for the tocotrienols. Under autoxidative conditions, stabilities in increasing order in methyl myristate were alpha-T = alpha-T-3 less than beta-T-3 less than gamma-T-3 less than delta-T-3 less than gamma-T less than delta-T = beta-T and in methyl linoleate were alpha-T less than alpha-T-3 less than gamma-T-3 less than beta-T less than gamma-T less than delta-T. Tocopherols were much more stable during autoxidation in methyl myristate than they were in methyl linoleate. In mixtures, there was no significant protection of alpha-tocopherol by either gamma- or delta-tocopherol under any of the conditions used. However, alpha-tocopherol was highly effective in protecting gamma- and delta-tocopherols in methyl myristate during both photolysis and autoxidation and in methyl linoleate during photolysis. During autoxidation in methyl linoleate, alpha-tocopherol protection of gamma- and delta-tocopherols after 24 hr was slight tough measurable.
在肉豆蔻酸甲酯和亚油酸甲酯的自动氧化和光解过程中，测定了选定的单个生育酚和生育三烯酚以及α-生育酚与γ-生育酚或α-生育酚与δ-生育酚等摩尔混合物的相对稳定性。含有0.05%适当生育酚或生育三烯酚的溶液在70℃下接受紫外线（254nm）照射或4.3ml/min的氧气流。生育酚（T）和生育三烯酚（T-3）通过气相色谱法测定，无需预先分离或纯化。在光解条件下，在肉豆蔻酸甲酯中稳定性由低到高的顺序为：γ-T-3＜α-T-3＜δ-T＜α-T＜γ-T＜5,7-T＜β-T；在亚油酸甲酯中为：α-T＜α-T-3≤γ-T-3≤β-T≤5,7-T＜γ-T＜δ-T。观察到5-甲基取代生育酚的光解初始速率存在溶剂效应，但5位未取代的生育酚或生育三烯酚不存在这种效应。在自动氧化条件下，在肉豆蔻酸甲酯中稳定性由低到高的顺序为：α-T = α-T-3＜β-T-3＜γ-T-3＜δ-T-3＜γ-T＜δ-T = β-T；在亚油酸甲酯中为：α-T＜α-T-3＜γ-T-3＜β-T＜γ-T＜δ-T。生育酚在肉豆蔻酸甲酯自动氧化过程中的稳定性远高于在亚油酸甲酯中的稳定性。在混合物中，在所使用的任何条件下，γ-或δ-生育酚对α-生育酚均无显著保护作用。然而，在光解和自动氧化过程中，α-生育酚在肉豆蔻酸甲酯中以及在光解过程中在亚油酸甲酯中对γ-和δ-生育酚具有高效保护作用。在亚油酸甲酯自动氧化过程中，24小时后α-生育酚对γ-和δ-生育酚的保护作用虽轻微但可测量。
