Protective effects of sulfated polysaccharides isolated from the enzymatic digest of Codium fragile against hydrogen peroxide-induced oxidative stress in in vitro and in vivo models

In the present study, the sulfated polysaccharides obtained from Codium fragile (CFCE-PS) were prepared by enzymatic digestion and ethanol precipitation, and the antioxidant properties of CFCE-PS were evaluated using both in vitro and in vivo models. CFCE-PS contained 76.84% sulfated polysaccharides, which comprised 55.78 +/- 3.00% of carbohydrate and 21.06 +/- 1.07% of sulfate. CFCE-PS scavenged hydroxyl, alkyl, and DPPH radicals with IC50 values of 1.21 +/- 0.01, 1.42 +/- 0.17, and 6.14 +/- 0.78 mg/mL, respectively. CFCE-PS remarkably protected Vero cells against hydrogen peroxide (H2O2)-induced damage by reducing the intracellular ROS level, increasing cell viability, and suppressing apoptosis in a dose-dependent manner. Furthermore, CFCE-PS significantly attenuated H2O2 -mediated oxidative stress in vivo in zebrafish. CFCE-PS dose-dependently improved the survival rate and normalized the heartbeat, as well as reduced ROS, cell death, and lipid peroxidation in H2O2-stimulated zebrafish. Taken together, these results demonstrated that CFCE-PS possesses strong in vitro and in vivo antioxidant activities, and it could be used as an ingredient in the functional food, pharmacy, and cosmetic industries.