Assessment of oxidative stress in Flathead mullet (Mugil cephalus) and Gilthead sea bream (Sparus aurata)

In this work we compared two species of fish with different feeding habits: Flathead mullet (Mugil cephalus) and Gilthead sea bream (Sparus aurata). The aim of this study was to evaluate total oxidant status (TOS), total antioxidant capacity (TAC) and TOS/TAC ratio (OSI), in order to highlight the presence of any differences and correlations in these two different species of fish. Thirty adult fish of Mugil cephalus and thirty of Sparus aurata were used. From each fish 0.6 ml of blood was collected. TOS and TAC indicators were measured in serum obtained from samples previously clotted and centrifuged. Our results showed statistically significant differences between the two species in TAC. TOS and OSI did not show significant differences between Gilthead sea bream and Flathead mullet. A positive relationship between TOS and TAC was found in Flathead mullet (Mugil cephalus), and a negative relation between TOS and TAC in Gilthead sea bream (Sparus aurata). Our study indicates that the oxidative status and the relationship between total oxidant status (TOS) and total antioxidant capacity (TAC) in serum are probably dependent on the fish species and are affected by different feeding habits.