Effect of Dietary Surfactin Supplementation on Parameters Related to Lipid Metabolism of Orange-Spotted Grouper

Abstract

This trial was conducted to investigate the effects of dietary surfactin supplementation on parameters related to lipid metabolism of orange-spotted grouper (Epinephelus coioides) juveniles. Three hundred and sixty fish were randomly divided into 6 treatment groups, and fed dietary surfactin levels: S0 (control group), S25, S50, S100, S150, and S200 mg/kg, respectively. Four replicates with 15 fish per tank were randomly assigned to each group. The trial period was 56 days. The lipid levels in serum, liver, and whole fish, and some lipid metabolism enzymes in the liver were measured. When compared to fish fed no surfactin, fish fed diets supplemented with surfactin presented lower levels of total cholesterol, triglyceride, low-density lipoprotein cholesterol, and higher levels of high-density lipoprotein cholesterol in serum; lower lipid levels in whole fish and liver (only 100 and 150 mg/kg surfactin groups) were observed. Dietary 100 mg/kg surfactin supplementation had the most influence on lipids level in serum, whole fish, and liver of orange-spotted grouper juveniles. Lower levels of fatty acid synthetase and higher activity of hepatic lipase and lipoprotein (lipase in liver) were affected only by 100 mg/kg surfactin supplementation in diet. The levels of acetyl CoA carboxylase were similar in all groups. This suggests that appropriate supplementation levels of surfactin in the diet of orange-spotted grouper juveniles might have beneficial effects on lipid metabolism to improve fish health status. The IJA appears exclusively as a peer-reviewed on-line open-access journal at http://www.siamb.org.il. To read papers free of charge, please register online at registration form. Sale of IJA papers is strictly forbidden.