新的滇桂艾纳香寡糖BROS结构分析

Structure Analysis of a New Oligosaccharides BROS from Blumea riparia

以滇桂艾纳香枝叶为原料,经陶瓷膜、有机膜分离,醇沉、Sevag法除蛋白,DEAE-纤维素柱层析和SephadexG-10,SephadexG-50凝胶柱色谱纯化得到的BROS;经HPGPC检测分析表明,BROS为均一寡糖,MALDI-TOF-MS测定分子量为1314.用IR,HPLC,甲基化分析,GC-MS,NMR(1H NMR,13C NMR,1H-1HCOSY,HMQC和HMBC)等方法对BROS结构进行表征,结果表明,该寡糖由1个葡萄糖(α-D-Glcp)和7个果糖(β-D-Fruf)组成,残基间以→2)Fruf-(1→链接,分子末端链接为α-Glcp-(1→,→2)-β-D-Fruf,推出BROS的结构式为:β-D-Fruf1-(2→1)-β-D-Fruf2-(2→1)-β-D-Fruf3-(2→1)-β-D-Fruf4-(2→1)-β-D-Fruf5-(2→1)-β-D-Fruf6-(2→1)-β-D-Fruf7-(2→1)-α-D-Glcp.

Blumea riparia oligosaccharide（BROS） was obtained from branches of Blumea riparia by us-ing ceramic and organic membrance separation,precipitation with ethanol,deproteination using Sevag method,and fractionation through DEAE-cellulose column,Sephadex G-10 and Sephadex G-50 Gel filtra-tion chromatography.The purity and molecular weight of BROS were determined by HPGPC and MALDI-TOF-MS.The structure was characterized with monosaccharide composition analysis,methylation analysis,IR,GC-MS,1D and 2D NMR analysis.The results showed that BROS was homogeneous oligo-saccharide and composed of one α-D-Glcp and seven β-D-Fruf.The molecular weight of BROS was 1314.The backbone of BROS had a consisting of 1,2-linked β-D-Fruf residues,α-D-Glcp-（1→ and β-D-Fruf-（2→ connecting each end of the molecular.Finally,the BROS structure was fixed on as： β-D-Fruf1-（2→1）-β-D-Fruf2-（2→1）-β-D-Fruf3-（2→1）-β-D-Fruf4-（2→1）-β-D-Fruf5-（2→1）-β-D-Fruf6-（2→1）-D-Fruf7-（2→1）-α-D-Glcp.