Effect of Different Carbon Sources on Antioxidant Properties of Exopolysaccharides Produced by Scleroderma areolatum (Agaricomycetes)

Five kinds of exopolysaccharides (EPS) were obtained by fermentation of Scleroderma areolatum Ehrenb. with sucrose, glucose, maltose, lactose, and fructose as carbon sources. Antioxidant abilities of the obtained EPSs were evaluated by inhibiting AAPH, HO, and glutathione (GS) induced oxidation of DNA and quenching 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonate) cationic radical (ABTS) and galvinoxyl radicals. The effects of carbon sources on the antioxidant properties of EPSs could be examined. The results showed that five EPSs can effectively inhibit radicals induced oxidation of DNA, and the thiobarbituric acid reactive substances (TBARS) percentages were 44.7%-80.8%, 52.3%-77.5%, and 44.7%-73.3% in inhibiting AAPH, HO, and GS induced oxidation of DNA, respectively. All five EPSs could scavenge ABTSand galvinoxyl, and exhibit superior activity in scavenging free radicals. Antioxidant abilities of EPS with fructose as carbon source were highest among five EPS.