Abid S L, Thiam S, Warner I M
Food and Industrial Oil Research, National Center for Agricultural Utilization Research, US Department of Agriculture, Peoria, IL 61604, USA.
J Chromatogr A. 2002 Mar 8;949(1-2):195-207. doi: 10.1016/s0021-9673(01)01272-9.
Capillary electrochromatographic (CEC) separations of unsaponifiable lipids, tocopherols (T), tocotrienols (T3), and plant sterols were studied under various conditions. Investigated stationary phases include pentafluorophenylsilica (PFPS), triacontylsilica (TCS), and octadecylsilica (ODS) phases. A baseline separation of four sterols (ergosterol, lanosterol, sitosterol and stigmasterol) on ODS was achieved and their elution order was found to be dictated by side-chain structures. CEC of the tocol-derived compounds on PFPS in aqueous methanol yielded the most satisfactory results with complete resolution of all components eluting in the order deltaT3>beta3>gammaT3>epsilonP>alphaT3>deltaT>zeta2T>betaT>gammaT>alphaT, while a reversal in elution of the epsilonT-alphaT3 pair was observed in aqueous acetonitrile. CEC with a TCS phase in non-aqueous methanol led to a different elution pattern deltaT3>gammaT3>betaT3>alphaT3epsilonT>deltaT>(zeta2+gamma)T>betaT>alphaT, despite favorable resolution of the (gamma-zeta2)T pair along with the observation of inseparable(beta-gamma)T and (beta-gamma)T3 pairs in non-aqueous dimethylformamide. Non-aqueous acetonitrile mobile phases provided unique selectivity for the (gamma-zeta2)T pair and isomer separations on TCS. Variations in separation and retention factors of relevant antioxidant species with CEC variables were evaluated. Examples of CEC quantification of unsaponifiable fractions of rice bran oils and soybean oils are presented.
在各种条件下研究了毛细管电色谱（CEC）对不皂化脂质、生育酚（T）、生育三烯酚（T3）和植物甾醇的分离。研究的固定相包括五氟苯基硅胶（PFPS）、三十烷基硅胶（TCS）和十八烷基硅胶（ODS）相。在ODS上实现了四种甾醇（麦角甾醇、羊毛甾醇、谷甾醇和豆甾醇）的基线分离，发现它们的洗脱顺序由侧链结构决定。在含水甲醇中，PFPS上生育酚衍生化合物的CEC产生了最令人满意的结果，所有组分按δT3>β3>γT3>εP>αT3>δT>ζ2T>βT>γT>αT的顺序完全分离，而在含水乙腈中观察到εT-αT3对的洗脱顺序相反。在非水甲醇中使用TCS相的CEC导致了不同的洗脱模式δT3>γT3>βT3>αT3εT>δT>(ζ2+γ)T>βT>αT，尽管在非水二甲基甲酰胺中（γ-ζ2）T对具有良好的分离度，同时观察到（β-γ）T和（β-γ）T3对无法分离。非水乙腈流动相为（γ-ζ2）T对和TCS上的异构体分离提供了独特的选择性。评估了相关抗氧化剂物种的分离和保留因子随CEC变量的变化。给出了米糠油和大豆油不皂化部分的CEC定量示例。
