| Two fractions of polysaccharide GRP and GRS were isolated from the crude water-soluble extraction of the roots of Panax ginseng C.A.Meyer by 1.0 M NaCl solution. The carbohydrate content of GRP and GRS was 99.84% and 81.70%, determining by the method of phenol-sulfuric acid. The uronic acid content of GRP was 97.31% according to the method of m-hydroxyphenyl. The result of HPLC showed that GRP was composed of GalUA with trace Glc, Ara and Gal. GRP was mainly consisted ofα-(1→4)-D-GalUA with branch at position 2 or 3 by the analysis of periodate oxidation, smith degradation and 13C NMR.GRS was divided into four fractions GRS1-â… , GRS2, GRS3-â…¡and GRS4 by ion chromatograph DEAE-Sepharose-CL-6B and molecular-exclusion chromatograph Sepharose-CL-6B, Sephadex-G-75. The monosaccharide composition of GRS1-â… , GRS2, GRS3-â…¡and GRS4 were Glc:Gal:Ara:Man=3.84:1:0.29:trace, Man:Glc:Ara:Gal:Rha:Xyl: GlcUA=0.23:0.54:0.40:1:0.029:0.026:0.028, Rha:GlcUA:GalUA:Gal:Ara=0.096:0.023: 0.033:1:0.73, Rha:GalUA:Gal:Ara=0.58:3.49:1:1.23 differently analysed by HPLC. The carbohydrate content of GRS1-â… , GRS2, GRS3-â…¡and GRS4 were 98%, 87.5%, 98%, 60% by the method of phenol-sulfuric acid. Based on the method of m-hydroxyphenyl, there is no uronic acid in GRS1-â… and the uronic acid content of GRS2, GRS3-â…¡and GRS4 were 4.4%, 3.8% and 58%. The molecular weight of GRS1-â… and GRS3-â…¡were 4611, 6065 which was measured by HPLC. GRS2 contain two main fractions analysed by the chromatograph of Sepharose-CL-6B. The main fraction of GRS4 on the chromatograph of Sepharose-CL-6B was mainly composed of uronic acid. Perioxidation, Smith degradation, Methlation analysis and 13C NMR indictated that GRS1-â… was definited asα-(1→4)-D-Glcp and a little ofβ-(1→6)-D-Galp; GRS3-â…¡was composed ofβ-(1→4)-D-Galp,β-(1→3)-D-Galp andα-(1→5)-D-Araf; The linkage of Gal in GRS2 was 1→4, 1→4,6 and the branch chain of GRS2 was complexed; The main linkage of GalUA in GRS4 was the ones which cannot be oxidated by periodate acid.
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