Purification, composition analysis and antioxidant activity of different polysaccharides from the fruiting bodies of Pholiota adiposa
Three water-soluble polysaccharide fractions (PAP1-1, PAP1-2 and PAP2-1) were isolated and purified from the fruiting bodies of Pholiota adiposa by diethylaminoethanol (DEAE) Sepharose fast flow column and superdexTM 200 column chromatography on an AKTA Purifier system. Results of high-performance size-exclusion chromatography (HPSEC) indicated that the average molecular weights of PAP1-1, PAP1-2 and PAP2-1 were 2.3 x 106 Da, 8.8 x 103 Da and 2.1 x 106 Da, respectively. Monosaccharide compositions analysis revealed that PAP1-1 and PAP2-1 were both mainly composed of glucose, and PAP1-2 was composed of rhamnose and glucose with a mole ratio of 1:3.61. The evaluation of antioxidant activity suggested that PAP1-1 with β-configuration glycosidic bond exhibited stronger scavenging activity of superoxide radical and hydroxyl radical than PAP1-2 and PAP2-1 contained both α- and β-configuration glycosidic bond, and should be explored as a novel potential antioxidant. Available data obtained with in vitro models suggested that antioxidant activity of polysaccharide may be related to the configuration of glycosidic bond.
Key words: Pholiota adipose, polysaccharide, purification, antioxidant activity.