O'Fallon J V, Busboom J R, Nelson M L, Gaskins C T
Department of Animal Sciences, Washington State University, Pullman 99164, USA.
J Anim Sci. 2007 Jun;85(6):1511-21. doi: 10.2527/jas.2006-491. Epub 2007 Feb 12.
A simplified protocol to obtain fatty acid methyl esters (FAME) directly from fresh tissue, oils, or feedstuffs, without prior organic solvent extraction, is presented. With this protocol, FAME synthesis is conducted in the presence of up to 33% water. Wet tissues, or other samples, are permeabilized and hydrolyzed for 1.5 h at 55 degrees C in 1 N KOH in MeOH containing C13:0 as the internal standard. The KOH is neutralized, and the FFA are methylated by H(2)SO(4) catalysis for 1.5 h at 55 degrees C. Hexane is then added to the reaction tube, which is vortex-mixed and centrifuged. The hexane is pipetted into a gas chromatography vial for subsequent gas chromatography. All reactions are conducted in a single screw-cap Pyrex tube for convenience. The method meets many criteria for fatty acid analysis, including not isomerizing CLA or introducing fatty acid artifacts. It is applicable to fresh, frozen, or lyophilized tissue samples, in addition to oils, waxes, and feedstuffs. The method saves time and effort and is economical when compared with other methods. Its unique performance, including easy sample preparation, is achieved because water is included rather than eliminated in the FAME reaction mixtures.
本文介绍了一种简化方案，可直接从新鲜组织、油脂或饲料中获取脂肪酸甲酯（FAME），无需事先进行有机溶剂萃取。采用该方案时，FAME合成在含水量高达33%的条件下进行。将湿组织或其他样品通透化并在含C13:0作为内标的甲醇1 N KOH中于55℃水解1.5小时。用硫酸中和氢氧化钾，并在55℃下通过硫酸催化使游离脂肪酸甲基化1.5小时。然后向反应管中加入己烷，涡旋混合并离心。将己烷吸取到气相色谱小瓶中用于后续的气相色谱分析。为方便起见，所有反应均在单个带螺旋盖的派热克斯玻璃管中进行。该方法满足脂肪酸分析的许多标准，包括不会使共轭亚油酸（CLA）异构化或引入脂肪酸假象。除油脂、蜡和饲料外，它还适用于新鲜、冷冻或冻干的组织样品。与其他方法相比，该方法节省时间和精力且经济实惠。其独特性能，包括易于样品制备，是因为在FAME反应混合物中包含水而非去除水而实现的。
