Structural characterization of corn silk polysaccharides and its effect in H2O2 induced oxidative damage in L6 skeletal muscle cells

To evaluate the antioxidant activity of polysaccharides from corn silk in H2O2 induced oxidative damage in L6 skeletal muscle cells. A polysaccharide (CSP2) was isolated from corn silk. Structure analysis of CSP2 with 1D and 2D NMR indicated that CSP2 was composed of (1 -> 6)-linked alpha-D-glucose. The substituent of the alpha-D-glucose is composed of (1 -> 3)-linked alpha-L-arabinose, (1 -> 4)-linked beta-D-galactose and (1 -> 3,5)-linked beta-D-mannose, with beta-D-xylose and alpha-L-rhamnose as terminal unit. CSP2 had the potential to scavenge DPPH and hydroxyl radical and inhibit hemolysis in vitro. CSP2 was found to suppress oxidant stress by improving the enzyme activities of SOD, CAT, and GPX. Rodamine 123 staining results showed that the pretreatment of CSP2 prevented changes in the mitochondrial membrane potential and increased the fluorescence intensity in L6 cells in the presence of H2O2. These results suggested that CSP2 could be utilized as a potential antioxidant supplement to prevent oxidative stress.