Chemical Structure of Water Soluble Polysaccharide from Spores of Ganoderma lucidum

OBJECTIVE To characterize the structure of homogeneous polysaccharide SGL-Ⅲ isolated from spores of Ganoderma lucidum..METHODS The physical characters of SGL-Ⅲ were determined by optical rotation test,HPLC and phenol-sulfuric methods.Then by means of partial hydrolysis with acid,periodate oxidation,Smith degradation,methylation,IR,GC,GC-MS and()~(13)C-NMR,the structure of polysaccharide SGL-Ⅲ was identified.RESULTS The molecular weight was estimated to be 1.41×10~(4).Sugar compositional analysis of SGL-Ⅲ indicated that it was composed of glucose and galactose in the molar ratio of 4.46∶1.SGL-Ⅲ was a low branched molecule.The main chain was made up of(1→3)-linked-Glc and(1→6)-linked-Gal.Some of(1→3)-linked-Glc residues were substituted at 6-O and some of(1→6)-linked-Gal were substituted at 2-O and 4-O.The(1→4)-linked-Gal and(1→6)-linked-Glc were on the side chain.The branch end was Glc.CONCLUSION The polysaccharide SGL-Ⅲ shows some characters of bioactive polysaccharide.We will investigate its bioactivities in the further work.