Determination of benzimidazoles in fish plasma by chromatographic method and their effects on metabolic and antioxidative enzymes activity

In the present investigation, two benzimidazole derivatives, fenbendazole (FBZ) and mebendazole (MBZ) were undertaken for pharmacokinetic study in Labeo rohita. Single oral doses of each FBZ and MBZ at 20 mg/kg were administered through feed to L. rohita juveniles. The blood was collected at 0.5, 1, 2, 4, 8, 12, 24, 30, 48, 72, 96 and 120 h intervals to determine the presence of parent benzimidazole derivatives concentration using High Performance Liquid Chromatography (HPLC). For FBZ, a maximum concentration (Cmax) of 1.32 ± 0.05 μg ml− 1 was measured at 4 h (Tmax), whereas the Cmax for MBZ of 1.66 ± 0.08 μg ml− 1 was detected at 8 h (Tmax) and the half-life (t1/2) was calculated as 16 h and 27.5 h for FBZ and MBZ, respectively. The transaminases enzymes (AST and ALT) activities were significantly higher (p < 0.05) in all benzimidazole treatments compared to control. However, the antioxidant enzymes (SOD, catalase and GST) activities were found significantly (p < 0.05) higher in MBZ treated group compared to FBZ and control. Thus, the results of present revealed that compared to MBZ, FBZ was absorbed quickly and depleted efficiently providing possible time for proficiently removal of helminths in L. rohita.