Comparison of Digestive Enzyme and Antioxidant EnzymeActivities of Amphiprion ocellaris Cultured inNatural Seawater and Artificial Seawater

【Objective】 The study was to investigate the changes of digestive enzyme and antioxidant enzyme activities in juvenile Amphiprion ocellaris cultured in natural seawater and artificial seawater. 【Method】 Natural seawater and artificial seawater culture experiments of A. ocellaris were carried out, and the samples were analyzed after being cultured for 6, 24, 48 and 96 hours to determine the activities of individual pepsin, intestinal amylase and various tissue antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and glutathione peroxidase (GSH) of kidney, spleen, liver, gill filament and muscle. 【Result】 The results showed that different culture treatments had significant effects on pepsin (the activity of pepsin of artificial seawater group was significantly higher than that of natural seawater group), but had no significant effect on amylase. There were tissue difference in antioxidant enzyme activities of juvenile A. ocellaris under different culture conditions. In the artificial seawater group, although the activities of antioxidant enzymes fluctuated with time, the law of the change was not obvious. Pepsin activity of juvenile A. ocellaris in artificial seawater group was lower than that in natural seawater group only at 6 h and higher than that in natural seawater at other time points, while the amylase activity showed reverse situation, namely, the pepsin activity was higher than that in natural seawater only at 6 h. The maximum SOD activity (36.70±3.55 U/mg) was obtained from the sampled muscle after being cultured for 48 h in artificial seawater. The maximum POD activity of gill filament and muscle presented in natural seawater at 96 h respectively, while that of other tissues presented in artificial seawater group. The maximum CAT activity of spleen presented in natural seawater at 24 h, and that of other tissues in the artificial seawater group. The maximum GSH activity of spleen and gill filament presented in natural seawater group at 96 h, and that of other tissues in artificial seawater group. 【Conclusion】 The results prove that the artificial seawater culture condition has certain stress on the juvenile A. ocellaris, the individual also has a certain regulation effect on the stress, and different tissues have different regulation functions.