Extraction and Antioxidant Activities of Polysaccharides Produced by Submerged Mycelia Culture of Oudemansiella raphanipes

Oudemansiella raphanipes is a commercially popular edible medicinal mushroom. The polysaccharides from O. raphanipes are the natural therapy for various metabolic diseases. Therefore, we have developed the optimal extraction conditions for extraction of polysaccharides from the mycelia of O. raphanipes and investigated their antioxidant activities. The optimal conditions of extracting polysaccharides from the mycelia of O. raphanipes were 85[degrees]C for 3.5 h, and the material-to-liquid ratio of 1:31. Under these conditions, the polysaccharides recovery was 91.89 mg/g, which was close to the predicted value (92.49 mg/g). In vitro antioxidant activity assays exhibited that the polysaccharides from the mycelia of O. raphanipes could effectively scavenge the 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid), and hydroxyl radicals, and it also exhibited the reducing power against [K.sub.3]Fe [(CN).sub.6]. These results suggested that the polysaccharides from the mycelia of O. raphanipes could be used as the source of natural antioxidants. Keywords: Antioxidant activity, Extraction, Fermentation, Mycelia, Oudemansiella raphanipes, Polysaccharides