基于电喷雾-四极杆-飞行时间质谱的高聚合度人乳寡糖异构体结构解析  

Structural Analysis of High Degree Polymerization Isomers of Human Milk Oligosaccharides Based on Electrospray Ionization-Quadrupole-Time of Flight Mass Spectrometry

作　　者：李欣 李佳齐 金高娃[2] 于龙[2] 郭志谋[2] 梁鑫淼[2] 刘帅 闫竞宇[2] LI Xin;LI Jia-Qi;JIN Gao-Wa;YU Long;GUO Zhi-Mou;LIANG Xin-Miao;LIU Shuai;YAN Jing-Yu(Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044, China;Key Lab of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics,Chinese Academy of Sciences, Dalian 116023, China)

机构地区：[1]大连医科大学基础医学院生物化学与分子生物学教研室,大连116044 [2]中国科学院大连化学物理研究所,中国科学院分离分析化学重点实验室,大连116023

出　　处：《分析化学》2019年第7期1106-1113,共8页Chinese Journal of Analytical Chemistry

基　　金：国家重点研发计划项目(Nos.2017YFD0400601,2016YFB0301502);国家自然科学基金项目(No.U1608255)资助~~

摘　　要：人乳寡糖是一类存在于人乳中的天然益生元,在促进婴儿肠道菌群生长、完善免疫系统功能和抵抗病原体侵染过程中发挥着不可替代的作用。人乳寡糖的功能与其结构密切相关,但其结构组成复杂、连接方式多样,存在大量的同分异构体,且随着寡糖聚合度的升高,同分异构体的数目和复杂性都急剧增加。因此,高聚合度的寡糖异构体的结构解析是人乳寡糖研究的难点之一,对寡糖的生物功能研究具有重要意义。本研究采用电喷雾-四极杆-飞行时间质谱(ESI-Q/TOF-MS),在负离子模式下对分离获得的18个高聚合度人乳寡糖(其中3个为首次报道)进行了结构解析,探讨了同组异构体之间碎片离子的差异,并详细总结了寡糖异构体的裂解规律,为复杂的高聚合度人乳寡糖异构体的结构解析及新型糖结构的发现提供了科学依据。Human milk oligosaccharides are a kind of natural prebiotics that exist in human milk. They play an irreplaceable role in the growth of infantile intestinal flora, the improvement of immune system and the resistance to pathogen infection. The function of human milk oligosaccharides is closely related to their structures which are complex with various linkages. Besides, the oligosaccharides have a large number of isomers, the number and complexity of which increase dramatically with the degrees of their polymerization. Therefore, the structural analysis of oligosaccharide isomers with a high degree of polymerization is one of the difficulties in the study of human milk oligosaccharides, and is of great significance for the study of the biological function of oligosaccharides. In this study, electrospray ionization-quadrupole-time of flight mass spectrometry (ESI-Q/TOF-MS) was used to analyze the structures of eighteen high-degree polymerized human milk oligosaccharides in a negative ion mode, and three of them were firstly reported. Differences of fragment ions between the isomers were discussed, and the cleavage rules of oligosaccharide isomers were summarized. This study provided a scientific basis for the structural analysis of the complex isomers of highly polymerized human milk oligosaccharides and the discovery of novel sugar structures.

关 键 词：人乳寡糖 同分异构体 结构解析 电喷雾-四极杆-飞行时间质谱 

分 类 号：R341[医药卫生—基础医学] O657.63[理学—分析化学]