摘要
腐殖质呼吸是近年来新发现的可参与环境污染生物降解的微生物能量代谢方式,腐殖质可作为氧化还原介体促进其他难降解污染物的生物还原,对有机污染物的降解转化具有重要意义.本研究采用响应曲面法优化菌株Citrobacter freundii的生长条件,并探究厌氧条件下Citrobacter freundii的醌还原广谱性;通过红外测定4种沉积物的官能团结构,探究Citrobacter freundii应用于河道沉积物修复领域的可行性.结果显示,当碳源比(葡萄糖/葡萄糖+柠檬酸钠)为0.691,碳源浓度为3.24 g·L^(−1),C/N(碳氮比)为15.096时,Citrobacter freundii的OD_(600)与α-AQS还原率的最大预测值分别为0.481及36.84%;Citrobacter freundii对萘醌和蒽醌类的醌类物均具有还原活性;所选4种河道沉积物均含有C=O官能团,与醌类物结构相似;优化后的Citrobacter freundii削减沉积物有机质速度远高于未优化的削减速度,42 d有机质削减率为14.61%.本研究验证了Citrobacter freundii醌还原特性,拓展了腐殖酸还原菌的应用领域,为沉积物修复提供了新手段.
Humus respiration is a newly discovered microbial energy metabolism that can participate in the biodegradation of environmental pollution in recent years.Humus can be used as a redox mediator to promote the biological reduction of other refractory pollutants,which is of great significance for the degradation and transformation of organic pollutants.In this study,response surface methodology was used to optimize the growth conditions of Citrobacter freundii,and to explore the quinone reduction broad-spectrum of Citrobacter freundii under anaerobic conditions.The functional group structure of four kinds of sediments was measured by infrared to explore the feasibility of Citrobacter Freundii application in the field of river channel sediment remediation.The results showed that when the carbon source ratio(glucose/(glucose+sodium citrate))was 0.691,the carbon source concentration was 3.24 g·L^(−1),and the C/N ratio was 15.096,the maximum predictive values of OD_(600) andα-AQS reduction rate of Citrobacter freundii were 0.481 and 36.84%,Citrobacter freundii has reductive activity on both naphthoquinone and anthraquinone quinones.The four selected river sediments contain C=O functional groups,which are similar to quinones in structure.The optimized Citrobacter freundii reduced the organic matter in sediments at a much higher rate than the unoptimized Citrobacter freundii,with a 42 d reduction rate of 14.61%.This study verified the reducing properties of Citrobacter freundii quinone,expanded the application field of humic acid reducing bacteria,and provided a new means for sediment remediation.
作者
张士伟
张超
黄建军
孙井梅
ZHANG Shiwei;ZHANG Chao;HUANG Jianjun;SUN Jingmei(School of Environmental Science and Engineering,Tianjin University,Tianjin,300350,China)
出处
《环境化学》
CAS
CSCD
北大核心
2022年第9期2986-2994,共9页
Environmental Chemistry
基金
国家自然科学基金(51778410)资助。
关键词
腐殖质呼吸
醌还原
响应曲面
河道修复
humus respiration
quinone reduction
response surface
river remediation
