Characterization and in vitro antitumor activity of polysaccharides from the mycelium of Sarcodon aspratus

Polysaccharides extracted from mushrooms have shown a variety of medical activities, such as antitumor, immunostimulatory and hypoglycemic activity. In this study, characteristics and the antitumor activities of Sarcodon aspratus polysaccharides were investigated for the possibility of application of S. aspratus in health care and medicine. Two polysaccharide fractions (PSAN and PSAA) were extracted and isolated from the mycelium of S. aspratus. The average molecular weight of PSAN and PSAA were approximately 5.6 × 104 Da and 3.83 × 105 Da, respectively. PSAN was composed of l-rhamnose, d-xylose and d-mannose, with molar ratios of 1:10:21; PSAA consisted of l-rhamnose, d-xylose, d-mannose, d-glucose and d-galactose, with molar ratios of 1:39:76:10:21. Both PSAN and PSAA presented high antitumor activity against Hela cells in vitro. At a concentration of 400 mg/L and an exposure time of 24 h, the inhibition rates for PSAN and PSAA were 65% and 80%, respectively. PSAN and PSAA exhibited significantly lower cytotoxicity against human normal liver cell line L-02 than Hela tumor cells in comparison with 5-Fu. Polysaccharide extracted from an edible mushroom S. aspratus may be a potential candidate for developing a novel low toxicity antitumor agent.