Biochemical Biomarkers as a Tool in Chromium Induced Toxicity to Green Tiger Prawn, Penaeus semisulcatus (De-Haan, 1844)

Abstract

Estuarine ecosystem and its biodiversity are at higher risk due to coastal contamination by heavy metals and conservation of biodiversity can be accomplished by utilizing biomarkers of pollutant at different exposure levels. In the present study, chronic toxicity test was conducted to evaluate the antioxidants and enzymes as the possible biomarkers in Green Tiger Prawn, Penaeus semisulcatus. The chronic endpoint value (MATC), no-observed effect concentration (NOEC), and low-observed effective concentration (LOEC) were also calculated to frame a criterion against chromium toxicity. The biochemical profiles such as total protein, catalase, lipid peroxidation, acetylcholinesterase, reduced glutathione, and glutathione-S-transferase activity were studied. The calculated no-observed effect concentration was 69.45 µg/l and low-observed effective concentration was 33.98 µg/l, the chronic value was 48.57 µg/l for 30 days by Dunnett’s procedure from background concentrations. Mortality was recorded to be 55 per cent in 80 µg/l on the 30th day of the toxicity test and was significant with other concentrations. Activity of catalase and glutathione-S-transferase, lipid peroxidation process and the amount of reduced glutathione significantly (p < 0.01) increased with consecutive increase in exposed chromium concentrations (5, 10, 20, 40, and 80 µg/l). The activity of acetylcholinesterase was found to be significantly (p < 0.01) reduced. Hence, catalase, lipid peroxidation, acetylcholinesterase, reduced glutathione, and glutathione-S-transferase activity was validated as the promising biomarkers for chromium toxicity with Penaeus semisulcatus.

Keywords: biochemical, catalase, chronic endpoint, esterase, glutathione-S-transferase, lipid peroxidation, reduced glutathione, total protein.