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本文报导了气相色谱和质谱联用利用电子电离 (EI)和化学电离 (CI)两种模式测定Natronobacteriummagadii中主要类脂的全甲基化衍生物的方法。实验数据显示 ,Natronobacteriummagadii和一般的原始细菌不一样 ,除含有传统的C2 0-C2 0 类脂甘油醚外 ,还存在一种不太常见的C2 0 -C2 5的类脂甘油醚。EI给出的碎片峰和CI给出的准分子离子峰使我们确证了C2 0 -C2 2 和C2 0 -C2 5结构的存在。质谱电子轰击法和化学电离法已成功地应用于测定原始细菌中主要不活泼类脂的烷基链结构 ,特别是电子轰击法的硬电离 ,获得了众多的烷基碎片峰 ,从而弥补了软电离ESI和APCI未能出现烷基碎片峰的不足。值得注意的是EI质谱显示出烷基是以直链 ,而并非有规律地按叔碳原子排列的支链 ,尽管这种说法尚需进一步确证
This paper reports a method for the determination of the full-methylated derivatives of major lipids in Natronobacterium magadii by gas chromatography and mass spectrometry using both ionization (EI) and chemical ionization (CI) modes. The experimental data show that Natronobacterium magadii is not the same as the common original bacteria, except for the traditional C2 0-C2 0 lipid glycerol ether, there is a less common C2 0 C2 5 glycerol ether. The fragmentation peak given by EI and the quasi-molecular ion peak given by CI gave us the confirmation of the existence of the C2 0 -C2 2 and C2 0 -C2 5 structures. Mass spectrometry electron bombardment and chemical ionization have been successfully applied to the determination of the alkyl chain structure of the major inactive lipids in primary bacteria, especially the hard ionization by electron bombardment, resulting in numerous alkyl fragmentation peaks, thus making up for the soft Ionization of ESI and APCI failed to show peaks of alkyl fragmentation. It is noteworthy that the EI mass spectrometry shows that the alkyl groups are branched, not regularly, by tertiary carbon atoms, although this statement needs further confirmation