一种饱和褐藻胶寡糖的制备方法

A method for preparation of saturated oligosaccharides from alginate

目的报道一种饱和褐藻胶寡糖的制备方法。方法以褐藻胶为原料,用酸水解法降解,在pH2.85处分级获得均聚古罗糖醛酸片段(PG)和均聚甘露糖醛酸片段(PM),分别在稀盐酸中水解(PG:pH3.8,120℃,3h;PM:pH4,120℃,4h)。水解物经凝胶渗透色谱法分离,获得寡糖组分,反复纯化后,获得系列褐藻胶寡糖。用红外光谱(IR)、核磁共振谱(NMR)、质谱(MS)等方法分析了寡糖的结构。结果褐藻胶经酸水解法降解,分离纯化后获得古罗糖醛酸寡糖二糖到六糖和甘露糖醛酸寡糖二糖到六糖,结构分析表明寡糖保持了原褐藻胶大分子的结构特征。结论本研究为褐藻胶低分子寡糖的制备提供了一种有效、简便的方法。

Objective To report a method for preparation of saturated oligosaccharides from alginate. Methods The alginate was degraded by acid hydrolysis, followed by fractionation at pH 2. 85 resulting in the homopolyguluronic acids （PG） and homopolymannuronic acids （PM）. The alginate derived homopolymers were further degraded by acid hydrolysis at pH 3.8, 120℃ for 3 h, and at pH 4, 120℃ for 4 h, respectively. The resulted acidic hydrolysates were separated by gel permeation chromatography to get oligosaccharide fractions, and the oligosaccharides were obtaind by repeated purification on gel chromatography. The structures of the oligosaccharides were characterized by analyses of infra red spectroscopy （IR）, nuclear magnetic resonance spectrometry （NMR）, and mass spectrometry （MS）. Results it was showed that the derived oligosaccharides were in saturated structures with the same structure characteristics as the original alginate macromolecule. Conclusion The method des cribed in this paper is a effective and convenient approach for the preparation of low-molecular-weight oligosaccharides from alginate.