Mercury Induced Biochemical Alterations As Oxidative Stress In Mugil Cephalus In Short Term Toxicity Test

J Rajkumar,Samuel Tennyson

doi:10.12944/cwe.8.1.06

Abstract

Mugil cephalus juveniles of size 2.5 ±0.6cm were exposed to mercury in short term chronic toxicity test through static renewal bioassay to detect the possible biochemical agent as biomarkers in aquatic pollution and in estuarine contamination as specific. Lipid peroxidation levels, glutathione S-transferase, catalase, reduced glutathione and acetylcholinesterase were studied as biochemical parameters.Increased thio-barbituric acid reactive substances levels were observed under exposure to mercury, leading to the oxidative damage resulting in lipid peroxidation. Decreased activities of antioxidants, catalase and increased glutathione-S-transferase under short term chronic exposures to mercury were more prominent in metal stress suggesting activation of physiological mechanism to scavenge the ROS produced. Decreased values of reduced glutathione on prolonged exposures to mercury indicate utilization of this antioxidant, either to scavenge oxy-radical or act in combination with other enzymes. The acetylcholinesterase activity was found to be decreased during mercury exposure. The results also suggest that mercury alters the active oxygen metabolism by modulating antioxidant enzyme activities, which can be used as biomarker to detect sub-lethal effects in aquatic pollution.

Highlights

Estuarine pollution is an ongoing activity started long back intensified during the last few decades, and currently the circumstances has become alarming, especially in India[1]
M. cephalus exposed to exposure concentrations experienced rigorous Oxidative stress (OS) characterized by significant alterations in biomarkers,were been observed in brain samples of the mullet[28]
Concentration of Lipid peroxidation (LPO) was significantly higher (P< 0.001) in higher concentrations of mercury due to increased levels of exposure indicating the importance of antioxidant[32].The level of total protein to mercury exposure significantly (P

Summary

Introduction

Estuarine pollution is an ongoing activity started long back intensified during the last few decades, and currently the circumstances has become alarming, especially in India[1]. Cellular measurements and its responses to chemical contaminants like heavy metals in test organisms are used as bio-indicators from aquatic environment allowing early detection of biological effects as well as assessment of the extent of contamination of pollutants[5,6].

Results

Conclusion