海参脂肪酸化学修饰气相色谱-质谱分析

以2-氨基-2-甲基丙醇为化学修饰试剂,柱前化学修饰气相色谱-EI质谱分析海参脂肪酸。通过修改官能团抑制了脂肪链中碳碳双键的移位,并使质谱呈现显示双健位置的规范信息。解析隐藏羧基的脂肪酸衍生物2-烯基-4,4-二甲基噁唑的质谱图,确定了海参不饱和脂肪酸中双键的位置。共鉴定出16种脂肪酸,由C14～C24脂肪酸组成,多不饱和脂肪酸相对含量为33.49%,其中5,8,11,14,17-二十碳五烯酸相对含量达18.26%,4,7,10,13,16,19-二十二碳六烯酸相对含量达6.65%,还检出了奇数碳链的14-二十三碳烯酸(相对含量为3.31%)。

Analysis of Chemically Modified Fatty Acids in Sea Cucumber by Gas Chromatography-Mass Spectrometry

A gas chromatography-electron impact mass specrometric method was developed for analyzing the compositions of the fatty acids in sea cucumber, whereas 2-amino-2-methylpropanol was used as the pre-column chemical modifying reagent for assaying the fatty acids. The functional group modilication effectively suppresses the migration of double bonds in the fatty acid chain and leads to regular informative mass spectra regarding to the position of the olefinic bonds in the chain. The position of double bonds of the fatty acids in sea cucumber were located by analyzing electron impact mass spectra of 2-alkenyl-4,4- dimethyloxazolines with a hidden carboxy1 as derivative of the fatty acids.According to the analysis of GC-EIMS, 16 fatty acids were identified. Sea cucumber consists of the fatty acids of C14～C24 and 33.49% of them are polyunsaturated fatty acids. The main components of the polyunsaturated fatty acids are 5,8,11,14,17-eicosapentaenoic acid and 4,7,10,13,16,19-docosahexenoic acid whose relative contents are 18.26% and 6.65% respectively. Besides, 14-tricosenoic acid (relative content 3.31%) with odd- numbered was identified.