Oxidative Stress, Reactive Oxygen Species (ROS) and Antioxidative Defense System, with Special Reference to Fish

Abstract

The concentration of oxygen in atmosphere is about 10%, whereas in aquatic environment it is about 0.3%. Since the availability of oxygen to aquatic animals is about 33 fold less than that of terrestrial organisms, oxygen concentration in the aquatic system is an important factor for regulation of fish health and reproduction. This paper reviews the knowledge of oxidative stress, ROS and Anti-oxidative defense system in various organisms and present status of information concerning oxidative stress in fish and attempts to resolve the reproductive consequences associated with oxidative stresses in fish under normal as well as different experimental states. Especially in fish there is a high risk of quality loss due to oxidation. Relatively few studies on the various antioxidants in fish are currently available. Studies on the interaction between the various endogenous antioxidants in fish are also very few. The relative concentration of antioxidants varies with the fish species as well as the type of fish muscle tissue. The quantity of these antioxidants may also fluctuate with storage time and handling post mortem. Control of lipid oxidation in fish involves utilizing processing and storage techniques that do not greatly decrease the activity of endogenous antioxidants.