Preparation and Antioxidant Activity Evaluation of Flammulina velutipes Polysaccharide/Fe(II) Chelate

In this study,the optimal conditions for the chelating reaction between Flammulina velutipes polysaccharide and Fe(Ⅱ) for achieving maximum chelating degree were investigated using single-factor method and response surface analysis,and evaluation of antioxidant activity of the obtained Flammulina velutipes polysaccharide/Fe(Ⅱ) chelate was performed. A maximum chelating degree of 86.21% was achieved when the reaction between Fe(Ⅱ) with an initial concentration of 6 mg/mL and Flammulina velutipes polysaccharide (3.54:1,mg/mg) was allowed to proceed for 6 h. Moreover,the antioxidant activity evaluation indicated that the abilities of Flammulina velutipes polysaccharide to scavenge hydroxyl and DPPH free radicals and the inhibitory effect against lecithin peroxidation were all improved after the chelation with Fe(Ⅱ).