Preparation And Quality Evaluation Of Polysaccharides Of Herbs Used In The Prescriptions Such As Yaotongning Capsule

The herbs containing polysaccharide in the prescription of Yaotongning capsule: Glycyrrhizae Radix Et Rhizoma, Herba Ephedrae, Cyathulae Radix, Atractylodis Rhizoma and herbs commonly used in the prescriptions for treating rheumatic diseases:Astragali Radix, Notogineseng Radix Et Rhizoma, Taxilli Herba, Epimedii Folium and guiding drug rice wine of Yaotongning capsule, were selected as material herbs. Their polysaccharides were extracted and purified; the quality and in vitro antioxidant activity of them were also evaluated.Using Astragali Radix as a case study, the conditions for extraction polysaccharides were optimized by single factor investigation combing orthogonal experimental design. Basing on the optimized technology and conditions, nine polysaccharides were extracted and purified. UV spectrophotometry was applied to test the content of polysaccharide, reducing sugar l-phenyl-3-methyl-5-pyrazolone (PMP) pre-column derivatization-high performance liquid chromatography (HPLC) was established to separate the nine monosaccharide include Man, Rib, Rha, GlcU, GalU, Glc, Gal, Xyl, Ara. And the method was applied to test the monosaccharide composition of nine polysaccharide samples. The difference evaluation of monosaccharide composition of the samples was achieved by principal component analysis (PCA). Five models including reducing capacity, ability of cleaning·OH,·O2-, DPPH radical, XOD inhibitory activity, were built to detect the in vitro antioxidant activity of the nine samples of polysaccharide.The results showed that the best conditions for preparing polysaccharide of Astragali Radix were:extract3.5h in boiling water, solid-liquid ratio of1:13, extract3times and sediment with60%ethanol. Sevag and macro porous resin method could be successfully applied in deproteinization and decoloration from the extracts, respectively. The other impurities were removed by ultrafiltration. Analysis results indicated that the nine polysaccharide samples contained a certain amount of reducing sugars and their polysaccharide contents were also different. The monosaccharide compositions of the nine polysaccharide samples were quite different. It suggested the primary structure of the nine samples were representative. There existed obvious activity-polysaccharide concentration dependence among the nine samples’antioxidant models of reducing capacity, cleaning·OH,· O2-and DPPH radical. While the inhibiting XOD activity of the nine samples were weak and there were no activity-polysaccharide concentration dependence. The rice wine polysaccharide related to Yaotongning capsule’s prescription had the highest activity of reducing and clearing DPPH radicals. The polysaccharides of Cyathulae Radix and Atractylodis Rhizoma, which were used in Yaotongning prescription, performed poorer in all five models when compared to the polysaccharides of the other four herbs, they had no obvious activity.