关键词: 米胚多糖, 硒多糖, 小鼠, 抗氧化性

Abstract: In this paper, acetic acid and nitric acid were used as the catalysts for selenium modification of rice embryo polysaccharides (REP), and the antioxidant properties of the native and modified polysaccharides (Se-REP1 and Se-REP2) were studied. The in vitro antioxidant activity was evaluated by using O2 -·, ·OH and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging capacity and reducing power assays. The antioxidant activity in vivo was evaluated by determining the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), malondialdehyde (MDA) and total antioxidant capacity (T-AOC) in mouse serum, liver, kidney and heart tissues. The results showed that all the native and modified polysaccharides at five concentrations had different O2 -·, ·OH and DPPH radical scavenging capacity, and their reducing power was increased with the increase of their concentration. Both Se-bound polysaccharides could improve the activity of SOD, GSH-Px and T-AOC in mice tissues and serum, and the effect was stronger than that of REP, but the activity of T-AOC in heart tissue was not significantly different between the modified and native polysaccharides. The contents of MDA in liver and kidney were much lower than that in the control group although the effect was not significant. On the other hand, the contents of MDA in serum and heart tissue showed an obvious significance, and administration of Se-bound REP prepared with acetic acid showed the highest antioxidant enzyme activity in mice.

Key words: rice embryo polysaccharide, selenium-bound polysaccharide, mice, antioxidant properties