Chemical analysis and antioxidant activity in vitro of polysaccharides extracted from Boletus edulis.

Boletus edulis is a well-known delicious mushroom. In this study, three crude polysaccharides (BEPF30, BEPF60 and BEPF80) were isolated from the fruiting bodies of B. edulis with boiling water. Chemical and physical characteristics of the three crude polysaccharides were investigated by the combination of chemical and instrumental analysis methods. Their antioxidant activities were investigated in vitro systems including hydroxyl assay, superoxide radical assay, reducing power and chelating activity. Among these three polysaccharides, BEPF60 showed more significant reducing power and chelating activity; and highest inhibitory effects on superoxide radical and hydroxyl radical. These results indicated that polysaccharides extracted from B. edulis might be employed as ingredients in healthy and functional food to alleviate the oxidative stress.