大黄多糖提取工艺对糖含量和糖醛酸含量的影响

 目的研究不同处理方法对大黄多糖(RTP)糖含量和糖醛酸含量的影响，以获得高品质的大黄多糖及能用于产业化生产的方法。方法用硫酸苯酚法测糖含量，硫酸咔唑法测糖醛酸含量，考马斯亮蓝测蛋白含量。通过对大黄多糖提取过程的糖含量和糖醛酸含量的监测，确定醇沉次数、除蛋白次数及方法；比较超滤法和凝胶柱法对大黄多糖不同分子量组分的影响，不同组分的纯度观察采用聚丙烯酰胺凝胶电泳。结果用冻融Sevag法联用除蛋白共7次、乙醇沉淀脱色6次，可获得较高糖含量(大于90%)和糖醛酸含量(大于20%)的大黄多糖；超滤截留法和凝胶柱法均获得5个分子量范围较窄的大黄多糖组分，超滤截留法分离效率高，成本低。结论本方法适宜用于产业化生产。

Effects of different extraction methods on polysaccharide and uronic acid contents of Rheum tanguticum polysaccharide

OBJECTIVE To study the effects of different extraction methods on the contents of polysaccharide and uronic acid extracted from Rheum tanguticum Maxim.ex Regel.METHODS The polysaccharide content was measured by Sulfuric acid-Phenol.The uronic acid content was measured by Sulfuric acid-Carbazole and the protein content was performed by Sevrage-Blue during the extracting procedure of Rheum tanguticum Polysaccharide(RTP).The number of times of ethanol sedimentary and that of protein precipitation by Sevag and freezing-thawing methods were determined.Comparison was performed between Sephacryl-S400 and Stirred cell methods to obtain different molecular weight fractions and the purity was measured by propylene polymer gel electrophoresis.RESULTS The satisfactory RTP was obtained by Sevag and freezing-thawing methods,removing protein seven times and discoloring with ethanol six times,respectively.Five different molecular weight fractions of RTP were obtained by Sephacryl-S400 and Stirred cell instrument,respectively.CONCLUSION Freezing-thawing method and ethanol sedimentary method were better than traditional methods and applicable to industrial manufacturing.