Characterization of Se-enriched Pleurotus ostreatus polysaccharides and their antioxidant effects in vitro.

Selenium-enriched polysaccharides have become a major research focus owing to their high anti-oxidant activities. Selenium-enriched Pleurotus ostreatus polysaccharide (Se-POP) and the native polysaccharide (POP) were obtained by hot water extraction from fresh fruiting bodies of P. ostreatus with or without selenium. Se-POP and POP had similar average molecular weights (0.95×104Da and 0.94×104Da, respectively). Se-POP was mainly composed of fucose, rhamnose, arabinose, galactose, glucose, and xylose, similar to the composition of POP, but in different molar ratios. In an FT-IR analysis, in comparison to POP, two new absorption peaks at 941cm-1 and 1048cm-1 were observed due to COSe and SeO bonds. In vitro study of DPPH, hydroxyl, and ABTS free radicals, Se-POP had a stronger antioxidant capacity than that of POP. Compared to POP, Se-POP had a superior ability to reduce hydrogen peroxide (H2O2)-induced oxidative stress and apoptosis in murine skeletal muscle (C2C12) cells. In general, selenium in Se-POP contributed to high antioxidant and biological activities. Se-POP acts as a potent antioxidant and has the ability to prevent oxidation via reactive oxygen species (ROS) and free radicals in humans. These results suggest that Se-POP is a candidate dietary supplement for functional foods.