Toxicity of Nonylphenol on Microcystis aeruginosa Mediated by the Ascorbate-glutathione (AsA-GSH ) Cycle

• 作者: Liu Ping Zhang Jiqiang Zhang Qiong
• 来源期刊: 气象与环境研究:英文版
• 学科: 地球科学
• 关键词: NONYLPHENOL Acute TOXICITY Antioxidant defense systems Ascorbate-glutathione CYCLE
• 年，卷（期）: 2019,（2）
• 页码范围: 78-82
• 页数: 5页
• 分类号: X171.5

摘要

Nonylphenol( NP) is a stable metabolic product of nonylphenol ethoxylates,which is widely used as an industrial surfactant. NP has been classified as an endocrine disrupter,and its toxicity to organisms can be biomagnified through the food chain. As compared with the endocrine disrupting effect,the toxicity of NP to organisms has not been studied intensively,and the toxicity mechanisms have often been ignored. In the present study,Microcystis aeruginosa,a freshwater alga belonging to the first level of the trophic chain,was chosen to detect the toxicity of NP. The mechanisms of toxicity mediated by the AsA-GSH cycle were explored. The acute toxicity of NP to M. aeruginosa within 96 h was studied and an EC50 concentration of 3. 45 mg/L was found. Further,the results showed that the toxicity of NP increased with the increase in concentration and exposure time. As compared with that in the control,the APX and MDHAR activities mostly increased,whereas DHAR activity fluctuated.However,the AsA content elevated at first,but decreased significantly after 72 h. For the GSH system,GR activity was always higher than that in the control. Nevertheless,the reduced GSH content was mostly inhibited. Therefore,the performance of AsA-GSH antioxidant defense system could explain the results of NP toxicity: the enzyme activities and antioxidant molecules increased initially,but an overall decline appeared after exposure for 24 h. This research is helpful for estimating the toxicity of NP integrally and improves people’s understanding of mechanisms of NP toxicity in algae.