Biochemical Responses of Protein and Lipid Levels to Polychlorinated Biphenyls (PCBs) Chronic Bioaccumulation in Labeo rohita

Abstract

Polychlorinated Biphenyls (PCBs) are known to accumulate in fat rich tissues due to their lipophilic characteristics, leading to bioconcentration and biomagnifications in the food chain. This accumulation poses risk to human health and the environment. The bioaccumulation of Polychlorinated Biphenyls in Labeo rohita can significantly impact their protein and lipid concentrations. The current research investigated how PCBs impact on protein and lipid levels in Labeo rohita under laboratory conditions. Labeo rohita belonging to the family Cyprinidae, weighing 25-30g procured from local fish dealer. Fish were acclimatized for a week at holding temperature of 18-22⁰C. Chronic PCBs Lc50 is 0.90 ppm for 28 days, PCBs deposition in tissues had increased significantly with dose and exposure duration dependent manner. The Lowry method was used to measure total protein concentrations, while lipid content was determined through Folch extraction method. The study results indicated that biochemical components showed a significant decrease which linked to increasing dosages of the treatment. The control group showed protein levels of 6.03 mg/g which decreased to 3.51 mg/g at 0.90 ppm (Lc50) while lipid levels dropped from 13.06 mg/g to 9.81 mg/g. (Lc50). The study reveals that, the PCBs exposure causes metabolic stress which results in the depletion of necessary biochemical reserves. The study demonstrates that Labeo rohita protein and lipid levels function as reliable biomarkers to evaluate how aquatic ecosystems experience toxicological effects and environmental contamination.