A novel polysaccharide with antioxidant, HIV protease inhibiting and HIV integrase inhibiting activities from Fomitiporia punctata (P. karst.) murrill (Basidiomycota, hymenochaetales).

A novel polysaccharide fraction (G) was obtained from the fungus Fomitiporia punctata (P. Karst.) Murrill. G exhibited a molecular weight of approximately 151kDa. The FT-IR results suggested that the monosaccharide components of G1 possessed furanoid rings and there were β-glycosidic bonds between the sugar units. TheH NMR results showed that G1 was composed of arabinose, fructose, galactose and glucose in the molar ratio of 1.6:3.8:19.7:19.7, as determined by gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC). G produced significant antioxidant effects as evidenced by its potency in inhibiting erythrocyte hemolysis, and in scavenging hydroxyl radicals and superoxide radicals. The highest rates of inhibition achieved were 73.58%, 36.55% and 50.98% respectively. In addition, G brought about 19.6% inhibition of HIV-1 protease activity at the concentration of 50μg/mL. G1 displayed inhibitory activity toward HIV-1 integrase in the concentration range of 100-1000μg/mL. The present study indicates that G from Fomitiporia punctate (P. Karst.) Murrill is a novel natural antioxidant.