基于超高效液相色谱-高分辨质谱法的油料作物脂质组学分析

Lipidomics Analysis of Oil Crops Based on Ultra-high Performance Liquid Chromatography-High Resolution Mass Spectrometry

针对油料脂质分子众多、结构难识别的难题,采用超高效液相色谱-高分辨质谱对油菜籽、大豆、花生、向日葵籽、玉米5种油料作物中脂质进行分析。使用反相色谱柱ACQUITY UPLC BEH C18(2.1 mm×100 mm,1.7μm)分离脂质,超高效液相色谱-高分辨质谱仪(UPLC-Orbitrap Fusion Mass)正、负离子模式下采集Data Dependent MS2数据,利用二级质谱碎片特征、精确分子质量、保留时间以及数据库匹配对脂质分子进行定性分析,获得脂质分子的唯一结构式。共鉴定出油料作物中132种脂质分子,包括8种甘油二酯(DG)、5种溶血磷脂酰胆碱(LPC)、2种溶血磷脂酰乙醇胺(LPE)、24种磷脂酰胆碱(PC)、18种磷脂酰乙醇胺(PE)、8种磷脂酰肌醇(PI)、1种磷脂酰甘油(PG)、1种磷脂酰丝氨酸(PS)以及65种甘油三酯(TG),并使用峰面积比进行相对含量的比较。该方法可以很好地实现脂质成分的分离,将油料作物中脂质成分的分析从脂肪酸分析水平提升到脂质分子层面,为更好地实现油料作物中脂质成分的应用提供了研究基础,并促进了脂质组学的发展。

Aiming at the scientific problem that oil crops contain a variety of lipid molecules which structures are difficult to identify,an ultra-high performance liquid chromatography-high resolution mass spectrometry was developed for the analysis of lipids in five kinds of oilseeds,i.e.rapeseed,soybean,peanut,sunflower seed and corn.Lipids were separated by using reversed-phase chromatographic column ACQUITY UPLC BEH C18(2.1 mm×100 mm,1.7 μm).In UPLC-Orbitrap Fusion Mass positive or negative ion mode,Data Dependent MS2 data were collected,and lipid molecules were characterized by using secondary mass spectrometry fragment characteristics,accurate molecular mass,retention time and database matching,then the unique structural formulas of the lipid molecules were obtained.A total of 132 lipid molecules in oil crops were identified in this research,including 8 diglyceride(DG),5 lysophosphatidylcholine(LPC),2 lysophosphatidyl ethanolamine(LPE),24 phosphatidylcholine(PC),18 phosphatidyl ethanolamine(PE),8 phosphatidyl inositol(PI),1 phosphatidyl glycerol(PG),1 phosphatidyl serine(PS) and 65 triglyceride(TG),then peak area ratio was used to compare their relative contents.This method could well realize the separation of lipid components and improve the analysis of lipid components in oil crops from the level of fatty acid analysis to the level of lipid molecules,and it provides a research basis for better application of lipid components in oil crops and promotes the development of lipidomics.