Isolation,Purification and Immunomodifying Activity of Polysaccharides from Phellinus igniarius

Phellinus igniarius polysaccharides were obtained by hot water extraction of mushroom fruit bodies followed by ethanol precipitation,and further purified by anion exchange and gel filtration chromatography.Immuno-enhancing activity was evaluated by determining the effect of different polysaccharide fractions on mouse spleen lymphocyte proliferation in vitro.Three crude polysaccharide preparations,designated PIP30,PIP60 and PIP80 according to the percentage concentration of ethanol required for precipitation from hot aqueous extracts,promoted lymphocyte proliferation to varying degrees.Purification of polysaccharide present in PIP30 and PIP60 was carried out using anion exchange chromatography.Proliferation rates in samples treated with 200 μg/mL of fractions P30U,P30W and P30S1(obtained following anion exchange chromatography of PIP30) were approximately 5-,4-,and 3.5-fold higher,respectively compared with negative controls.Similarly,marked increases(3.4-and 2.8-fold) in cell proliferation rates compared with negative controls were observed with 200 μg/mL concentrations of P60W and P60S2(obtained following anion exchange chromatography of PIP60),respectively.Two purified polysaccharide preparations,P60W1-1 and P60S1-1,were obtained following gel filtation chromatography of fractions P60W1 and P0S1,respectively.Fraction P60W1-1(10-100 g/mL) enhanced splenocyte proliferation 0.5-1.4-fold compared with negative controls,whereas no effects were observed with P60S1-1.