藻毒素介导下硫酸盐还原菌与硫形态的响应变化及其衍生的生物毒性效应  

Response changes of sulfate-reducing bacteria and sulfur forms mediated by microcystins and their de-rived biotoxic effects

作　　者：曹琳 吴昊 徐怡婷 徐毅成 丰亚茹 叶文涛 吴湘[1,2] CAO Lin;WU Hao;XU Yiting;XU Yicheng;FENG Yaru;YE Wentao;WU Xiang(College of Life Sciences,Huzhou University,Huzhou 313000;Key Laboratory of Aquatic Resources Conservation and Development Technology Research,Huzhou 313000;Zhejiang Huzhou Ecological and Environmental Monitoring Center,Huzhou 313000)

机构地区：[1]湖州师范学院生命科学学院,湖州313000 [2]浙江省水生生物资源养护与开发技术研究重点实验室,湖州313000 [3]浙江省湖州生态环境监测中心,湖州313000

出　　处：《环境科学学报》2024年第12期435-442,共8页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金面上项目(No.31772855);浙江省自然科学基金青年科学基金项目(No.LQ12B07001);湖州市公益性应用研究项目(No.2021GZ53);浙江省尖兵领雁计划项目(No.2022C02058);国家级大学生创新创业训练计划项目(No.202410347053)。

摘　　要：硫化物浓度是养殖水体监控的重要指标,高浓度的硫化物极易对水生生物造成毒害.藻毒素是养殖水体中普遍存在且毒性较强的有机污染物.为探究藻毒素介导下不同形态硫化物的响应变化及其衍生的生物毒性效应,本研究以微囊藻毒素-LR(MC-LR)为暴露污染物构建微型养殖环境,测定水体中不同形态硫化物浓度的变化,并对沉积物中硫酸盐还原菌(SRB)群落多样性进行分析;同时设置相关浓度硫化物为暴露污染物,以日本沼虾为受试生物,开展硫化物急性毒性暴露试验.结果表明,MC-LR暴露组中水体还原性硫化物浓度显著升高,沉积物中硫化物含量也同步增加;此外,沉积物中SRB群落组成及结构也发生了相应的改变.在还原性硫化物急性毒性暴露下,日本沼虾肌肉组织中过氧化氢酶活性和总抗氧化能力提高,琥珀酸脱氢酶和乳酸脱氢酶活性下降,可见受试沼虾体内抗氧化能力和呼吸代谢能力均受到不同程度的损伤.综上可知,藻毒素是影响养殖环境中硫酸盐还原菌以及硫化物形态和含量的重要因素,进而对水生生物也会带来负面影响.Sulfide concentration,critical for monitoring in aquaculture,could be severely toxic at high levels to aquatic organisms.Algal toxin,such as microcystins,has been a common and highly toxic organic pollutant in aquaculture water.In order to explore the response changes of sulfate-reducing bacteria and sulfur forms mediated by microcystins and their derived biotoxic effects.Using microcystin-LR(MC-LR)as an exposure pollutant,a micro-culture environment was constructed to measure the changes in the concentration of different forms of sulfide in the water,and analyze the community diversity of SRB in the sediment.Concurrently,an acute toxicity experiment was conducted on Macrobrachium nipponense using sulfides as the exposure contaminants to assess biotoxic effects at relevant concentrations.The results showed that the concentration of reducible sulfides in the water of MC-LR exposed group increased significantly,and the sulfide content in the sediment also increased.In addition,the composition and structure of SRB communities in the sediments also changed.Under acute toxic exposure to reducible sulfides,the catalase activity and total antioxidant capacity in the muscle tissue of Macrobrachium nipponense increased,while the activities of succinate dehydrogenase and lactate dehydrogenase decreased.These findings indicate that the antioxidant capacity and respiratory metabolic capacity of tested shrimp were impaired to varying degrees.In conclusion,microcystin would be a key factor affecting the diversity of sulfate-reducing bacteria and the forms and concentrations of sulfides in aquaculture environments,which would also bring negative effects on aquatic organisms.

关 键 词：微囊藻毒素 硫酸盐还原菌(SRB) 硫化物 日本沼虾 毒性效应 

分 类 号：S949[农业科学—水产养殖]