基于MALDI质谱成像技术分析莲子中代谢物的组织分布

该文建立了一种可对莲子中多种代谢物进行高覆盖分析的基质辅助激光解吸附质谱成像(MALDI-MSI)方法,实现了莲子中生物碱类、黄酮类、氨基酸类、脂肪酸类、有机酸类、胆碱类、磷脂类等多种代谢物的组织原位可视化表征。结果表明,生物碱类代谢物主要分布在莲子胚芽中;黄酮类代谢物主要分布在莲子胚芽和种皮中;氨基酸类代谢物在莲子子叶中的含量显著高于莲子胚中;脂肪酸类代谢物在莲子不同组织中的分布差异很小;胆碱类代谢物在莲子胚芽和莲子子叶底部的含量更高,甘油磷酸胆碱在莲子子叶顶部的含量更高;有机酸类代谢物以及绝大多数磷脂类化合物在莲子子叶中的含量高于莲子胚。该研究为评价莲子药物质量、探究莲子中化合物的时-空代谢网络提供了新的技术支持。

Analysis on Tissue Distribution of Metabolites in Lotus Seed by MALDI Mass Spectrometry Imaging Technique

A high-coverage matrix-assisted laser desorption/ionization mass spectrometry imaging(MALDI-MSI)method was developed to visualize the spatial locations of a wide spectrum of metabolites in lotus seed in this paper,in which the spatial locations of alkaloids,flavonoids,amino acids,fatty acids,organic acids,cholines and phospholipids in lotus seed were successfully imaged.Results suggested that the alkaloids are mainly distributed in the lotus seed germ,the flavones are mainly located in the lotus seed germ and lotus seed skin,the levels of amino acids in lotus seed cotyledon are significantly higher than that in the lotus seed embryo,there are few distribution differences of fatty acids in different tissues of lotus seed,the levels of choline in the lotus seed germ and the bottom of the lotus seed cotyledon are higher than those in other tissue regions,glycerophosphocholine mainly distributes in the apex of the lotus seed cotyledon,and the levels of organic acids and most phospholipids in the lotus seed cotyledon are higher than that in the lotus seed embryo.This study provides a new way to investigate the drug quality and the metabolic networks of lotus seed.