Purification, composition analysis and antioxidant activity of different polysaccharide conjugates (APPs) from the fruiting bodies of Auricularia polytricha

In this study, four purified polysaccharides (APPsA-1, APPsB-1, APPsB-2 and APPsC-1) were derived from the fruiting bodies of Auricularia polytricha by size-exclusion chromatography and ion-exchange chromatography on an ÄKTA explore 100 purification system. Chemical and physical characteristics of four purified polysaccharides were investigated by a combination of chemical and instrumental analysis methods. On the basis of hydroxyl radical assay, superoxide radical assay and Fe2+-chelating ability assay, the antioxidant activities of APPsA-1, APPsB-1, APPsB-2 and APPsC-1 were investigated. The results showed that all fractions exhibited antioxidant activities in a concentration-dependent manner, and the higher the content of uronic acid, the stronger the antioxidant activities of APPs. Therefore they should be developed as new antioxidant agents.