Holmbäck J, Karlsson A A, Arnoldsson K C
Department of Chemistry, Organic Chemistry, Royal Institute of Technology, Stockholm, Sweden.
Lipids. 2001 Feb;36(2):153-65. doi: 10.1007/s11745-001-0702-z.
Two polar lipid classes, both with three acyl groups, were isolated from an extract of oats and characterized by nuclear magnetic resonance spectroscopy, electrospray mass spectrometry (MS), and electron ionization MS (EIMS). Distortionless enhancement by polarization transfer (DEPT) and the two-dimensional correlation experiments 1H-detected heteronuclear multiple quantum coherence spectroscopy, heteronuclear multiple bond correlation spectroscopy, double quantum filtered correlation spectroscopy, and total correlation spectroscopy provided sufficient information for determination of the structure of the two lipid classes. The polar lipid classes were found to be N-acylphosphatidylethanolamine [1,2-diacyl-sn-glycero-3-phospho-(N-acyl)-1'-ethanolamine; N-acyl-PE] and acylphosphatidylglycerol [1,2-diacyl-sn-glycero-3-phospho-(3'-acyl)-1'-sn-glycerol]. High-performance liquid chromatography with electrospray ionization MS (HPLC-ESMS) and with electrospray ionization tandem MS (HPLC-MS/MS) were utilized for the separation and subsequent determination of molecular species. With HPLC-ESMS, ions of deprotonated molecules were obtained and with HPLC-MS/MS carboxylate ions (representing acyl groups) were obtained as well as other structurally significant ions. Fifty molecular species of N-acylphosphatidylethanolamine and 24 molecular species of acylphosphatidylglycerol were found, with a molecular mass range of 924-1032 Da and 959-1035 Da, respectively. Identification of the fatty acid isomers, as picolinyl ester derivatives, was done with gas chromatography with EIMS. Three isomers of 16:1 fatty acids were found in N-acyl-PE, and their double bond positions were determined to 6, 9, and 11 with a relative abundance of 4:10:1.
从燕麦提取物中分离出两类均含有三个酰基的极性脂质，并通过核磁共振光谱、电喷雾质谱（MS）和电子电离质谱（EIMS）对其进行了表征。极化转移无畸变增强（DEPT）以及二维相关实验，即1H检测的异核多量子相干光谱、异核多键相关光谱、双量子滤波相关光谱和全相关光谱，为确定这两类脂质的结构提供了足够的信息。发现这两类极性脂质分别是N-酰基磷脂酰乙醇胺[1,2-二酰基-sn-甘油-3-磷酸-(N-酰基)-1'-乙醇胺；N-酰基-PE]和酰基磷脂酰甘油[1,2-二酰基-sn-甘油-3-磷酸-(3'-酰基)-1'-sn-甘油]。采用高效液相色谱-电喷雾电离质谱（HPLC-ESMS）和高效液相色谱-电喷雾电离串联质谱（HPLC-MS/MS）对分子种类进行分离和后续测定。通过HPLC-ESMS获得去质子化分子的离子，通过HPLC-MS/MS获得羧酸盐离子（代表酰基）以及其他具有结构意义的离子。发现了50种N-酰基磷脂酰乙醇胺分子种类和24种酰基磷脂酰甘油分子种类，其分子量范围分别为924 - 1032 Da和959 - 1035 Da。通过气相色谱-EIMS将脂肪酸异构体鉴定为吡啶基酯衍生物。在N-酰基-PE中发现了三种16:1脂肪酸异构体，其双键位置确定为6、9和11，相对丰度为4:10:1。
