Preparation and antioxidant activity of rice germ Zn2+-polysaccharide

The polysaccharide was extracted from rice germ The polysaccharide complex of rice germ zinc was prepared with polysaccharide and zinc sulfate as raw materials and its activity was studied. The results showed that the optimum preparation conditions were as follows: the mass ratio of polysaccharide to zinc sulfate ( 1.000∶ 0.800) , the p H value of the solution was 6.0, the reaction temperature was 65 ℃, and the reaction time was 2.5 h. Under these conditions, the content of zinc in the zinc polysaccharide complex was ( 5.617 ± 0.279) mg/g. In addition, the scavenging rate of DPPH free radicals was 57.76% and62.15% respectively.The scavenging rate of superoxide anion radical was 60.11% and 67.44% respectively.The scavenging rate of hydroxyl radical was 56.94% and 61.89%.The reduction force increases with increasing concentration.It could be seen that the polysaccharide of rice germ had more antioxidant activity than rice germ polysaccharide.