Structural characterization and in vitro antitumor activity of a novel polysaccharide isolated from the fruiting bodies of Pleurotus ostreatus

摘要

A novel water-soluble polysaccharide(POPS-1)was obtained from the fruiting bodies of Pleurotus ostreatus by hot water extraction,ethanol precipitation,and fractionated by DEAE-cellulose ion exchange chromatography and sepharose CL-6B gel filtration chromatography using an ATKA explore 100 purifier.The structure characterization and antitumor activity of the POPS-I were evaluated in this paper. According to GC analysis, HPGPC,FT-IR,partial acid hydrolysis, periodate oxidation and Smith degradation,methylation and GC-MS analysis,the results indicate POPS-1(M-w=31 kDa)was composed of Man; Gal;Glc with a molar ratio of 1:2.1:7.9, it had a backbone of beta-(1 ->3)-linked glucose residues,which occasionally branches at O-6. The branches were composed of(1->3)-linked Glc,(1->4)-linked Gal,(1->4)-linked Man, and terminated with Glc and Gal residues. Cytotoxicity assay showed POPS-1 presented significantly higher antitumor activity against Hela tumor cell in vitro,in a dose-dependent manner,and exhibited significantly lower cytotoxicity,to human embryo kidney 293T cells than Hela tumor cells compared with 5-Fu.The results suggest POPS-1 may be considered as a potential candidate for developing a novel low toxicity antitumor agent.