College of Chemistry and Environmental Science, Henan Normal University, Xinxiang, Henan Province 453007, China.
J Agric Food Chem. 2009 May 27;57(10):4212-7. doi: 10.1021/jf900657f. Epub 2009 Apr 15.
Interest in conjugated linolenic acid (CLnA) and conjugated linoleic acid (CLA) as functional lipids is growing. The present study was (i) to study the oxidative stability of individual CLnA isomers and (ii) to compare the oxidative stabilities of CLnA and CLA with their corresponding nonconjugated counterparts, α-linolenic acid (LN) and linoleic acid (LA). The oxidation was carried out in air at 50 °C and monitored by the gas-liquid chromatography (GC) and the oxygen consumption test. First, it was found that CLnA was most unstable followed by CLA, LN, and LA in decreasing order. Second, analyses of silver ion high-performance liquid chromatography (Ag(+)-HPLC) demonstrated that t,t,t-CLnA isomers had greater stability than c,t,t-CLnA and c,t,c-CLnA isomers. Finally, both green tea catechins (GTCs) and butylated hydroxytoluene (BHT) were capable of preventing the CLnA oxidation, with the former being more effective than the latter.
人们对共轭亚油酸（CLnA）和共轭亚麻酸（CLA）作为功能性脂质的兴趣与日俱增。本研究（i）旨在研究各个 CLnA 异构体的氧化稳定性，（ii）比较 CLnA 和 CLA 与相应非共轭对应物α-亚麻酸（LN）和亚油酸（LA）的氧化稳定性。在 50°C 的空气中进行氧化，并通过气液色谱（GC）和耗氧量测试进行监测。首先，发现 CLnA 最不稳定，其次是 CLA、LN 和 LA，稳定性依次降低。其次，银离子高效液相色谱（Ag(+)-HPLC）分析表明，t,t,t-CLnA 异构体比 c,t,t-CLnA 和 c,t,c-CLnA 异构体更稳定。最后，绿茶儿茶素（GTCs）和丁基羟基甲苯（BHT）都能够防止 CLnA 氧化，前者比后者更有效。
