<正>测定了植物膜脂中磷脂酰甘油（ＰＧ） 在硫酸、三氟化硼、氢氧化钾催化时，酯交换甲酯化反应产物的脂肪酸组成和ＰＧ 中各种酰基脂肪酸的相对甲酯化率，表明酸催化产物的脂肪酸组成比较稳定，碱催化时ＰＧ 中各种酰基脂肪酸的相对甲酯化率在室温－ １５ ｍｉｎ 有最大值，此后随温度升高或反应时间增加，各种酰基脂肪酸的相对甲酯化率均下降，其中以反式－ Δ３ －十六碳单烯酸的相对甲酯化率下降最为明显，表明其甲酯较其他脂肪酸甲酯易碱分解。因此ＧＣ 分析方法测定膜脂中脂肪酸组成时，宜用酸催化甲酯化方式。

Fatty acid compositions in the products of transmethylesterification of plant phosphatidylgly cerol catalyzed by H 2SO 4、BF 3 and KOH under different reaction conditions were measured and the relative methy lesterification yields (REY) of individual acyl fatty acids were given.In the fatty acid compositions there was no significant change when catalyzed by acid.On the contrary,with the increase of temperature or time the relative content of trans 3 hexadecenoic acid (16∶1(3t))in the products and the REY of all acyl fatty acids decreased when catalyzed by alkali.The decrease of both relative content and REY of 16∶1(3t) was the most notable phenomenon which showed that the 16∶1(3t) was more liable to decompose than other fatty acids when catalyzed by alkali.