一种简单的方法用于分析磷脂酰胆碱的位置。

A simple method for positional analysis of phosphatidylcholine.

机构信息

Department of Chemistry, Wrocław University of Environmental and Life Sciences, Norwida 25, 50-375 Wrocław, Poland.

出版信息

Food Chem. 2012 Dec 15;135(4):2542-8. doi: 10.1016/j.foodchem.2012.07.005. Epub 2012 Jul 20.

DOI:10.1016/j.foodchem.2012.07.005

Abstract

Simple and fast method of positional analysis of fatty acid composition of phosphatidylcholine (PC) from egg-yolk and soy has been elaborated. The key step of the procedure was complete ethanolysis of PC catalyzed by sn-1,3 specific lipase from Mucor miehei (Lipozyme). 2-Acyl-lysophosphatidylcholine (2-acyl LPC), fatty acids ethyl esters (FAEEs) and free fatty acids (FAs) were formed in this process. No acyl migration was observed during the reaction. The products were entirely separated from the products mixture by simple extraction in water:hexane (2:3 v/v) system. The hexane fraction containing free FAs and FAEEs was treated with BF(3)/Et(2)O in ethanol to obtain only FAEEs. The analysis of FAEEs by GC gave the composition of the FAs in the sn-1 position of the PC. 2-Acyl LPC from water fraction after precipitation in cold (-20°C) acetone was converted into FAEEs and analyzed by gas chromatography (GC) to determine FAs composition in the sn-2 position of the PC.

摘要

已经详细阐述了一种从蛋黄和大豆中磷脂酰胆碱（PC）脂肪酸组成进行定位分析的简单快速方法。该方法的关键步骤是由米根霉 sn-1,3 特异性脂肪酶（Lipozyme）催化的 PC 完全乙醇解。在此过程中形成了 2-酰基溶血磷脂酰胆碱（2-acyl LPC）、脂肪酸乙酯（FAEEs）和游离脂肪酸（FAs）。反应过程中没有观察到酰基迁移。通过在水：正己烷（2:3 v/v）体系中进行简单萃取，可以将产物完全从产物混合物中分离出来。含有游离 FAs 和 FAEEs 的正己烷馏分用 BF(3)/Et(2)O 在乙醇中处理，仅得到 FAEEs。通过气相色谱（GC）分析 FAEEs 可得到 PC 的 sn-1 位脂肪酸组成。冷（-20°C）丙酮沉淀水相后的 2-acyl LPC 被转化为 FAEEs，并通过气相色谱（GC）进行分析，以确定 PC 的 sn-2 位脂肪酸组成。