Structural analysis and antioxidant activities of polysaccharides from cultured Cordyceps militaris

The polysaccharides extracted by hot water and precipitated by 50% ethanol from the fruiting bodies of cultured Cordyceps militaris (W-CBP50) were introduced. Antioxidant activities of W-CBP50, W-CBP50 I (obtained from W-CBP50 purified by Sephadex G-100 chromatography) and W-CBP50 II (obtained from W-CBP50I purified by Sephadex G-200 chromatography) were evaluated and structural features of W-CBP50 II were analyzed. The polysaccharide W-CBP50 II was able to scavenge the stable free radical 1,1-diphenyl-2-piciylhyrazyl (DPPH), while W-CBP50 and W-CBP50I could scavenge DPPH, hydroxyl and superoxide radical. Structural characteristics of W-CBP50 II were investigated using GPC, GC-MS, H-1 NMR and IR. The results showed that it was mainly composed of alpha-glucose, alpha-mannose, alpha-galactose and alpha-arabinose with alpha-type glycosidic linkage and the molecular weight of its main component was 8.97 kD. (C) 2013 Elsevier B.V. All rights reserved.