磺胺二甲嘧啶废水处理系统中Exiguobacterium sp.H-1的分离及其环境适应特性  

Isolation of Exiguobacterium sp.H-1 from the sulfamethazine wastewater treatment system and its environmental adaptation characteristics

作　　者：陈田 王壮 芦梦瑶 陈研 周佳[1] 屈建航[1] 潘婧诗 罗宇[1] CHEN Tian;WANG Zhuang;LU Mengyao;CHEN Yan;ZHOU Jia;QU Jianhang;PAN Jingshi;LUO Yu(College of Biological Engineering,Henan University of Technology;College of International Education,Henan University of Technology)

机构地区：[1]河南工业大学生物工程学院 [2]河南工业大学国际教育学院

出　　处：《环境工程技术学报》2024年第1期258-267,共10页Journal of Environmental Engineering Technology

基　　金：国家自然科学基金项目(42107139);河南工业大学高层次人才科研启动基金项目(2019BS046);河南工业大学青年骨干教师培育计划(21421206)。

摘　　要：磺胺二甲嘧啶(SMZ)是一种难降解的广谱抗生素,其广泛存在已对水环境构成严重的威胁。微生物是环境中抗生素降解转化的主要驱动者,但高效降解SMZ的微生物资源匮乏。以SMZ废水处理系统的活性污泥为原料,采用纯培养技术从中分离筛选出一株SMZ降解菌H-1。经形态学观察、生理生化特征、16S rRNA基因序列分析,H-1归属于微小杆菌属(Exiguobacterium sp.)。通过单因素试验研究初始SMZ浓度、接种量、pH和温度对菌株H-1降解SMZ效果的影响。结果表明,接种量、pH和温度对该菌株降解SMZ的影响较大。进一步采用响应面法优化菌株Exiguobacterium sp.H-1降解SMZ的最佳条件,得出pH为7.21,温度为28.86℃,接种量为4.40%时,其对5 mg/L SMZ降解率为10.54%。本研究发现微小杆菌Exiguobacterium sp.H-1具有降解SMZ的能力,其降解SMZ的独特之处是能够将SMZ脱去SO_(2),生成嘧啶环和苯胺环,经过耦合生成N-(4,6-二甲基嘧啶-2基)-1,4-二苯胺,然后进行脱氨反应,生成2-苯-4,6-二甲基嘧啶,随后去甲基化生成产物6(2-苯基-1,2-二氢嘧啶,m/z为159.97)。此外,菌株H-1在0~10%NaCl的广泛范围内也表现出很强的耐盐性,能够为SMZ污染水体的生物修复提供耐盐能力强的微生物菌株资源。Sulfamethazine(SMZ)is a broad-spectrum antibiotic that is difficult to degrade,and its widespread presence poses a serious threat to the aquatic environment.Microorganisms are the main drivers of antibiotic degradation and transformation in the environment,but microbial resources for efficient degradation of SMZ are limited.Therefore,a strain of SMZ-degrading bacteria H-1 was isolated and screened from the activated sludge of SMZ wastewater treatment system by the pure culture technique.The strain H-1 was classified as the genus of Exiguobacterium sp.based on its morphological observation,physiological and biochemical characteristics,and 16S rRNA gene sequence analysis.The effects of initial SMZ concentration,inoculum,pH and temperature on the degradation of SMZ by strain H-1 were investigated by a single-factor test,and it indicated that the inoculum,pH and temperature affected greater on the degradation of SMZ by strain H-1.The optimal conditions for the degradation of SMZ by strain Exiguobacterium sp.H-1 were further optimized by response surface methodology:pH 7.21,temperature 28.86℃,inoculum level 4.40%,and its removal efficiency of 5 mg/L SMZ was 10.54%.It is found for the first time that Exiguobacterium sp.H-1 has the ability to degrade SMZ,and it is able to remove SMZ from SO_(2) first to produce pyrimidine and aniline rings,which are coupled to generate N-4,6-dimethylpyrimidin-2-yl)-1,4-diphenylamine,and then the deamination reaction proceeds to produce 2-phenyl-4,6-dimethylpyrimidine,which is subsequently demethylated to produce product 6(m/z=159.97).In addition,strain H-1 also shows a strong salt tolerance within a wide range of 0-10%NaCl,providing a resource of salt-tolerant microbial strains for the bioremediation of SMZ-polluted waters.

关 键 词：磺胺二甲嘧啶 Exiguobacterium 生物降解 环境适应性 生物修复 

分 类 号：X172[环境科学与工程—环境科学]