Biological and physicochemical properties of two polysaccharides from the mycelia of Grifola umbellate

In the present study, we firstly reported the antioxidant, antitumor and immunomodulatory effects of two polysaccharides (GUMP-1-1 and GUMP-1-2) isolated from Grifola umbellata mycelia. Chemical analysis indicated that two polysaccharide fractions contained different content of neutral sugar, uronic acid and protein, as well as varying monosaccharide compositions and average molecular weight. We found that they could significantly inhibit the growth of H22 implanted tumor and enhance the spleen index and splenocyte proliferation of H22 tumor-bearing mice. In addition, GUMP-1-2 had the stronger free radicals scavenging and ferrous ion chelating abilities than GUMP-1-1 in vitro. These results indicated that antitumor activity of two purified polysaccharides might be achieved by improving immune response and the different chemical composition and average molecular weight could affect their antitumor, antioxidant and immunomodulatory activities.