Characterization and antioxidant activities of the polysaccharides from mycelium of Phellinus pini and culture medium

Two polysaccharides isolated and purified from the mycelium (PPM) and its culture medium (PPE) of Phellinus pini using gel filtration were subjected to composition analysis and valuated for the antioxidant activity. The average molecular weights of PPM and PPE were approximately 22.0 and 38.0 kDa, respectively. PPM and PPE were both neutral heteropolysaccharides consisting of mannose, galactose, and glucose with molecular ratios of 2.99:1.00:0.34 and 38.40:1.00:1.76, respectively. In vitro antioxidant assay, PPM and PPE could scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and hydroxyl radical, chelate ferrous ion and reduce ferric ion. The antioxidant activities of PPM were stronger than those of PPE, suggesting that PPM has significant potential as a natural antioxidant agent.