氯氰菊酯暴露对龙须菜的胁迫影响  

Responses of the macroalga Gracilaria lemaneiformis to the stress of cypermethrin,a pyrethroid insecticide

作　　者：王朝晖[1,2] 岳文洁[1] 康伟[1] 杨宇峰[1,2] 

机构地区：[1]暨南大学水生生物研究所,广州510632 [2]热带亚热带水生态工程教育部工程研究中心,广州510632

出　　处：《环境科学学报》2010年第8期1658-1665,共8页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金项目(No.40873065;U0633006;4077306);广东省科技计划项目(No.2007B030200002)~~

摘　　要：在实验室条件下研究了不同浓度氯氰菊酯胁迫下,龙须菜的生长状况及藻体生理生化指标变化情况.结果表明,龙须菜对氯氰菊酯敏感性较低,氯氰菊酯浓度低于100μg.L-1时对龙须菜生长的抑制作用不明显.在氯氰菊酯胁迫的24h内,龙须菜体内的叶绿素a、藻红蛋白、可溶性蛋白、可溶性糖含量以及超氧化物歧化酶(SOD)活性均呈现出低浓度(<5或<10μg.L-1)促进、高浓度(>10或>50μg.L-1)抑制的现象.在本研究设置的氯氰菊酯浓度下(1～100μg.L-1),膜脂过氧化产物丙二醛(MDA)含量均增加,呈现典型的剂量-反应关系,由氧自由基所引起的膜脂过氧化是氯氰菊酯对龙须菜产生毒害作用的重要原因.低浓度暴露早期SOD的激活以及蛋白质和糖类的促进作用对于抵抗氯氰菊酯的过氧化胁迫具有重要作用,但在高浓度氯氰菊酯胁迫下,SOD的失活致使氯氰菊酯对龙须菜产生明显毒性作用.The growth behavior and physiological responses to pyrethroid stresses were investigated through the exposure of Gracilaria lemaneiformis to different concentrations of cypermethrin.The growth of G.lemaneiformis was less sensitive to cypermethrin compared to microalgae and aquatic animals,and low cypermethrin（100 μg·L-1）did not inhibit the growth.However,quick and significant physiological responses occurred when G.lemaneiformis was experienced to cypermethrin,and all biochemical parameters varied significantly within 24 h exposure.Chlorophyll a（Chl.a）,phycoerythrin,（PE）,soluble protein,soluble sugar,malondialdehyde（MDA）,and superoxide dismutase（SOD）activity was significant enhanced at low concentrations（5 or 10 μg·L-1）while was inhibited at high concentrations of cypermethrin（10 or 50 μg·L-1）.A general dose-dependence increase in MDA level was observed under the cypermethrin concentrations of this experiment（1~100 μg·L-1）,which reveals that the toxic effect of cypermethrin was probably exerted through lipid peroxidation by free radical generation.Our results suggest that the activation of SOD and promotion of protein and sugar content at early exposure under low concentrations are important to counteract the oxidative stress induced by cypermethrin,and the inactivation of SOD at high concentrations may be crucial to the growth inhibition of G.lemaneiformis by cypermethrin.

关 键 词：氯氰菊酯 龙须菜 生长 光合色素 SOD MDA 

分 类 号：X171.5[环境科学与工程—环境科学]