Effects of mercury on antioxidant mechanisms in the marine phanerogam Posidonia oceanica

Diseases of Aquatic Organisms

L. Ferrat¹  M. Roméo¹  C. Pergent-Martini¹  M. Gnassia-Barelli¹ 

关键词: Posidonia oceanica;    Mercury;    Glutathione S transferase;    Catalase;    Lipid peroxidation;    Oxidative stress;   

DOI  :  10.3354/dao050157

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: Biochemical markers of oxidative stress such as catalase activity, glutathione S-transferase (GST) activity and levels of lipid peroxidation evaluated in terms of thiobarbituric acid reactive substances (TBARS) were measured in the sheaths ofthe marine phanerogam Posidonia oceanica (L.) Delile experimentally exposed to 0.01, 0.1 and 1 µg Hg l^-1 for 48 h. Up to a threshold concentration of 0.1 µg Hg l^-1, an increase in catalase and GST activities and TBARS levelswas observed, indicating that the antioxidant mechanisms were overtaxed and could not prevent membrane lipid peroxidation. Paradoxically, at 1 µg Hg l^-1, the damage seemed to decrease, as the lipid peroxidation levels of exposedsheaths were lower than those of controls and as catalase and GST activities were not different from those of controls. A possible rapid induction of phytochelatins detoxifying mercury could occur at this high level of mercury.

【 授权许可】

Unknown