Abstract:Dictyophora echino-volvata Zane, a kind of the edible Dictyophoraindusiata species, has various bioactivities. Three fractions, named as DEP-4P, DEP-6P and DEP-8P, were fractionated using gradual ethanol precipitation method from the water soluble extract of Dictyophora echino-volvata Zane. The yields of DEP-4P, DEP-6P and DEP-8P were 27.4%, 6.1% and 1.8%, successively. The contents of neutral sugar in DEP-4P, DEP-6P and DEP-8P ranged from 96.2% to 88.2%. No protein and uronic acid were detected. DEP-4P, DEP-6P and DEP-8P were identified as polysaccharides with high purity by high performance gel permeation charomatograph method. The relative molecular weights of DEP-4P, DEP-6P and DEP-8P were calculated to be 2.1×104, 6.5×103 and 1.9×103 u, successively, by referring to the molecular weights of dextran standards. Glucose was the major monosaccharide among the three fractions, while that there was trace amounts of mannose in DEP-8P. FT-IR spectra of the polysaccharides indicated that they may be α-glucans. Scanning electron micrographs showed that DEP-4P and DEP-6P performed as sheet-like appearance, while DEP-8P presented pod or line-like shape. All above, α-glucans with different molecular weights and topographic characteristics were successfully isolated from crude extract of Dictyophora echino-volvata Zane, which could lay a good foundation for further investigations in the structural features, functional proterties and applications.