早熟禾细胞膜脂肪酸衍生化方法比较

Comparison of three derivatization methods for the determination of fatty acid profiles in cell membranes for bluegrass(Poa pratensis)

脂肪酸是生物膜的重要组成部分,由于植物细胞不同生物膜特性也不同,同一种酯化方法对不同生物膜脂肪酸酯化后测定分析的结果很难获得满意效果。为了寻找一种比较简单、可靠的衍生化方法,该研究以早熟禾叶片为材料,采用三种衍生化方法分别对其叶绿体、线粒体、液泡及细胞质膜这4种膜脂肪酸衍生化,随后进行GC定量测定分析。结果表明:相对于BF_3-甲醇和HCl-甲醇两种酯化法对部分膜脂肪酸衍生化程度较低,氯乙酰酯化法对这4种膜脂肪酸的衍生化效率高、程度完全,GC测定结果重复性好、准确率高。该研究结果为其他相关植物细胞的不同膜脂肪酸测定分析提供了一定的理论借鉴。

The characteristic difference in bio-membrane in plant cells makes it difficult to use the same esterification method to determine the fatty acids contents,which are the important component of cell biological membrane. In order to establish a simple and reliable esterification method,in the present study,we isolated four kinds of cell membranes,chlo-roplasts,mitochondria,vacuoles and cytoplasm membrane respectively. Their fatty acids were extracted,esterified and de-termined by gas chromatography （GC） following three different methods. The results showed that both BF3-methanol and HCl-methanol esterification methods could not effectively esterify some of the fatty acids in mitochondria. Compared with the two approaches,acetyl chloride method could trans-esterify fatty acids completely and efficiently. Our data on fatty acids analysis with GC determination indicated that the third method had a high repeatability and accuracy. The current study provides valuable information for fatty acid determination on the plant cell membranes from different species.