Abstract: The study on isolation and property of exopolysaccharides from Armillaria mellea was conducted.The following results were obtained : The fermentation broth was concentrated. Then alcohol was put thrice into it .The precipitate attained was eluted again with 75% alcohol .The protein was eliminated with Sevage method.Furthermore,the DEAE-cellulose column chromatography was used on the exopolysaccharide purification and the column was eluted with the distilled water and NaCl solution from 0.05～0.5mol/L.Neutral and several kinds of acid polysaccharides were obtained . The purification of the neutral polysaccharide was made with SephadexG-150 chromatography.The pure polysaccharide A was collected. The IR spectrum of the polysaccharide A showed a character of β-glycosidic bond in 400～4000cm-1.After the polysaccharide A was hydrolyzed, the hydrolysate was analyzed with the silica gel pellicular chromatography and filter paper chromatography . While both the chloroform:methanol(60:40) and acetone:H2O(96:4) were used as the disperse agent and the dische reaction was used as dyestuff, the results proved that polysaccharide was composed of glucose. The polysaccharide was colored by coomassie brilliant blue G-250, and coomassie brilliant blue R-250 after polysaccharide electrophoresis. It proved that there was not any protein remained in the polysaccharide A.

Key words: Armillaria mellea , Submerged fermentation , Exopolysaccharide , Isolation and purification , Polysaccharide property