Effect of Curcumin on Iron Toxicity and Bacterial Infection in Catfish (Clarias gariepinus).

Abstract

Iron is an essential element that involved in many vital physiological functions in fish, while excess iron concentration causes many toxic effects. Curcumin is a natural popular spice that used as a dietary supplementation and has iron chelating properties. This study was conducted to evaluate the effect of curcumin on iron toxicity in catfish (Clarias gariepinus). Also this study assess the antibacterial effect of curcumin against Vibrio anguillarum infection. Clarias gariepinus were orally exposed to low and high doses of curcumin (40, 80 mg kg-1 fish) for 3 weeks. Fish were then exposed to 25 mg L-1 of ferric chloride as a source of iron toxicity for another 3 weeks. Some hematological parameters (Total and differential white blood cells count, total red blood cells count, hemoglobin concentration and hematocrit %) and biochemical parameters (Serum ferritin, transferrin, ALT, AST, protein and albumin) were assessed before and after exposure to iron. Iron residues in gills, spleen, liver, kidney, abdominal fats, gonads and muscles were also determined. Moreover the determination of fish survivability after bacterial challenge with Vibrio anguillarum was recorded. Iron caused decrease in total white blood cells count (WBCs), increase in ferritin level and elevation in liver function enzymes (ALT and AST). However, the pretreatment of fish with curcumin significantly increased WBCs, lymphocyte percentage, ferritin level and protein and albumin concentrations with significantly decreased transferrin, ALT and AST levels. Also there were significant decreases in iron concentration in serum, kidney, gonads and muscle in both low and high curcumin pretreated groups compared to Fe group. Results indicated a modulatory effect of curcumin against iron toxicity in catfish, also curcumin had an immune-stimulant effect against Vibrio anguillarum infection.