Antioxidant Complex of the Black Sea Bivalve Flexopecten glaber ponticus (Bucquoy, Dautzenberg et Dollfus, 1889) in a Natural Habitat

Abstract

The antioxidant (AO) defense complex in tissues of the scallop Flexopecten glaber ponticus (Bucquoy, Dautzenberg et Dollfus, 1889) from a natural habitat in the Black Sea is studied for the first time. The results indicate a pronounced tissue specificity of the scallop AO complex along with close levels of TBA-reactive substances in all the studied organs. In the gills of the scallop, the activity of glutathione reductase (GR), superoxide dismutase (SOD), and catalase is higher than in the hepatopancreas. The activity of glutathione peroxidase (GP), GR, and catalase in the gills is higher than in the muscle. The reduced glutathione (GSH) reserve in the gills is lower than in the hepatopancreas. This indicates that both the glutathione system and the key antioxidant enzymes, SOD and catalase, significantly contribute to the antioxidant defense of the scallop gills. In the hepatopancreas, the level of glutathione is the highest and the activity of GP is high and similar to that in the gills. This reflects their significant role in the AO defense of this organ. However, the activity of GR, SOD, and catalase in the hepatopancreas is significantly lower than in the gills. The scallop muscle is characterized by the lowest GP activity and a low GSH level, close to that in the gills. The SOD activity in the muscle is comparable to its value in the gills, and the activity of catalase and GR is comparable to the values in the scallop’s hepatopancreas.