一种判定多糖中有无糖醛酸残基的简易新方法

New simple method to detect uronic acids in polysaccharides

目的 建立一种判定多糖中有无糖醛酸残基的简便可靠的方法。方法 采用 TL C分析了含糖醛酸的多糖还原前后的样品以及标准葡聚糖分别酸水解 2和 4h的产物 ,以探讨传统 TL C方法是否可靠。并将含糖醛酸的多糖及中性多糖完全酸水解产物进行 TL C检测 ,糖醛酸标准品为对照 ,以苯胺 -邻苯二甲酸显色检测糖醛酸 ,此外 ,考察了其灵敏度 ,并与已有的方法比较。结果 传统方法中的荧光斑点系由 CF3COOCH3以及反应过程中其他副产物产生的 ,并非糖醛酸产生。新法可检测出 0 .5 μg的糖醛酸 ,无假阳性结果。结论 传统方法缺乏必要的理论依据 ,容易误导结构研究。以糖醛酸标准品为对照 ,对多糖样品完全酸水解产物进行薄层层析后 ,采用苯胺

Object To develop a simple and reliable method to detect the presence of uronic acids in polysaccharides Methods Uronic acid containing polysaccharides and standard glucons were subjected to acid hydrosis for 2 h and 4 h respectively. Samples of the products, before and after hydrolysis were analyzed by TLC using standard uronic acid as the control and aminobenzen alizaric acid as the chromogenic agent, to compare the sensitivities in the detection of uronic acid used in the present conventional analysis. Results The fluorescent spots used as criterion in traditional TLC method were not shown by uronic acids, but by CF 3COOCH 3 and other by products in reaction 0 5 μg of uronic acid could be detected with our method, without false positive reaction Conclusion The traditional TLC method seemed to lack theorectical background and may mislead structural study The present method in more reliable to detect uronic acids in polysaccharides by analyzing the complete hydrolytic products of polysaccharides using TLC with standard uronic acids as control and aminobenzene alizaric acid as chromogenic agent