杂合褐藻糖胶寡糖的制备及结构分析

Preparation of Hybrid Fucoidan-derived Oligosaccharides and Their Structural Analysis by Negative-ion Electrospray Tandem Mass Spectrometry

采用热水提取法从海蒿子(Sargassum pallidum)中得到一个杂合的褐藻糖胶(SPF);采用稀酸水解和低压凝胶渗透色谱(LPGPC)分离得到一系列杂合硫酸寡糖.结合单糖组成、甲基化和电喷雾碰撞诱导串联质谱(ES-CID-MS/MS)分析表明,所得21个寡糖属于杂化岩藻寡糖硫酸酯,主要由α1→3连接的Fuc及少量β1→4连接的Xyl和β1→6连接的Gal组成;硫酸基取代位点主要存在于Fuc的C4或C2位、Xyl的C2位和Gal的C4位;Fuc主要存在于寡糖的非还原端.实验结果表明,ES-CID-MS/MS技术可用于各种杂合褐藻糖胶寡糖的结构序列分析.这些结构多样的硫酸寡糖可进一步点印到糖芯片上,研究其与蛋白相互作用.

Acomplex sulfated fucoidan （SPF） was obtained by hot water extraction from Sargassum pallidum. A series of hybrid oligosaccharides were acquired by mild acid hydrolysis with low pressure gel permeation chromatography （LPGPC）. Based on the monosaccharides composition, methylation and electrospray collisioninduced dissociation mass spectrometry（ES-CID-MS/MS） analysis, 21 kinds of oligosaccharides were sulfated hybrid fucoidan-derived oligosaccharides. The resulted oligosaccharides were mainly composed of a1---3 linked Fuc, β1-4 linked Xyl and β1--6 linked Gal. The sulfation occurred at C4 or C2 of fucose, C2 of xylose and C4 of galactose residue, respectively. Most of fucose residues were present in nonreducing terminal of oligosaccharides. The technique of ES-CID-MS/MS was suitable for the sequences analysis of other hybrid oligosaccharides of various fucoidans. More importantly, all these diverse sulfated oligosaccharides can be printed onto the glycol-chip, and studying their interactions with proteins.