基于柱前衍生-超高效液相色谱-质谱联用技术的植物提取液中氨基化合物代谢谱分析

氨基化合物在植物生长发育中起着重要作用。本文建立了一种基于柱前衍生-超高效液相色谱-质谱联用技术的植物提取液中氨基化合物代谢谱的分析方法。以烟草鲜叶为例,共检测出87种氨基化合物。其中43种氨基化合物的定量分析结果表明,方法的线性相关系数在0.993~0.999之间,线性范围可达到4个数量级,检出限为0.03~6.58 ng/mL,日内、日间精密度分别为0.7%~15.6%、0.8%~22.9%,回收率为74.4%~122.7%。采用该方法考察了打顶对不同部位烟草鲜叶中氨基化合物代谢谱的影响,结果显示打顶处理对上部叶影响最大,打顶后上部叶氮代谢主要流向生物碱合成方向。该方法充分利用了三重四极杆串联质谱和高分辨串联质谱技术的优势,可实现植物提取液中氨基代谢物的高选择性、高灵敏度分析。

Metabolic profiling analysis of amino metabolites in plant extract based on pre-column derivatization-ultra high performance liquid chromatography-mass spectrometry

Amino metabolites are important compounds that play a key role in plant growth and development. A metabolic profiling analysis method of amino metabolites in plant extract was developed based on pre-column derivatization-ultra high performance liquid chromatography-mass spectrometry. Using the tobacco leaf as an example, a total of 87 amino metabolites, including amino acids, amines, peptides, alkaloids etc. were detected. The repeatability of the method was good with RSDs of 85 amino metabolites between 1.5% and 18.8%. Forty-three amino metabolites validated by standard samples showed good linearity with the correlation coefficients of 0.993-0.999, covered linear range of four orders of magnitude. The limits of detection were 0.03-6.58 ng/mL. The intra-day and inter-day precisions were 0.7%-15.6% and 0.8%-22.9%, respectively. The recoveries were 74.4%-122.7%. The influence of topping on metabolic profiling of amino metabolites in fresh tobacco was investigated using the developed method. The results showed that the amino metabolites in the upper tobacco leaves were most affected than those in the middle and lower leaves. Metabolism of amino metabolites in the upper leaves after topping was mainly towards the alkaloid synthesis. The method integrated the advantages of triple quadrupole mass spectrometry and high resolution quadrupole-time of flight mass spectrometry. It can be used for metabolic profiling analysis of amino metabolites in plant extract with high sensitivity and selectivity.