Basic Violet-1 Dye Induced Variation in Antioxidative Enzymes Leads to Neurotoxicity in Labeo rohita

The present study explored the potential use of brain anti-oxidative enzymes as pollution biomarkers in fish Labeo rohita. Experiments were conducted to see the neurotoxic effects of dye Basic violet-1 on fish brain enzymes such as lactate dehydrogenase, alkaline phosphatase and acid phosphatase. Acute toxicity tests were performed for 96 hrs with dye concentrations of 0.2 (LC20), 0.4 (LC40), 0.6 (LC60), 0.8 (LC80) and 1 (LC100) mg/l to study biochemical changes. Behavioural observations were also recorded. Recovery experiments were run for 15 and 30 days. Exposure to the dye adversely affects the brain of the fish as evidenced by altered swimming behavior. Significant dose and duration-dependent increase in enzyme activity was recorded for alkaline phosphatase and acid phosphatase while lactate dehydrogenase activity showed a decrease when compared to the control. Lactate dehydrogenase was found to be a maximally affected enzyme as the percentage change over control is 301.26%. The results indicate prolonged neurotoxic effects of the dye as indicated by the altered swimming behaviour and enzymatic profile of fish. The present study recommends the use of L. rohita as sentinel species in water quality studies and supports the incorporation of fish biochemical profiles as a biomarker in water/ wastewater monitoring programs.