Protective effect of fucoidan against AAPH-induced oxidative stress in zebrafish model

•This study was designed to assess in vitro and in vivo anti-oxidant effect of fucoidan.•The protective effects were determined via oxidative stress in zebrafish.•Fucoidan possess a protective effect against AAPH-induced oxidative stress. Fucoidan, extracted from Ecklonia cava, has been extensively studied because of its wide biological activities. However, antioxidative activities have not been yet examined. Therefore we evaluated in vitro and in vivo studies on antioxidative activities of E. cava fucoidan (ECF). ECF exhibited more prominent effects in peroxyl radical scavenging activity, compared to the other scavenging activities. Thus, ECF was further evaluated for its protective ability against 2,2′-azobis dihydrochloride induced oxidative stress in Vero cells and ECF strongly reduced the AAPH-induced oxidative damage through scavenging intracellular reactive oxygen species. Furthermore, we evaluated protective effect of ECF against AAPH-induced oxidative stress in zebrafish model. ECF significantly reduced ROS generation, lipid peroxidation and cell death in zebrafish model. These findings indicate that ECF has antioxidant activities in vitro Vero cells and in vivo zebrafish model, even though ECF is not a polyphenol or flavonoid compound and does not contain benzene rings or conjugated structures.