Antioxidant acitivity of low molecular weight hyaluronic acid

► Hyaluronic acid was partially degraded by sulfate radical to afford low molecular weight hyaluronic acid (LMWHA). ► LMWHA showed strong inhibition of lipid peroxidation and hydroxyl radical scavenging activity in vitro. ► LMWHA was able to overcome cyclophosphamide-induced immunosuppression in mice. ► LMWHA was able to significantly raise the antioxidant enzymes activities in immunosuppressed mice.