两株耐重金属普罗维登斯菌属异养硝化好氧反硝化菌的分离及脱氮特性  

Isolation and nitrogen removal characteristics of two heavy metal-tolerant heterotrophic nitrifying-aerobic denitrifying strains of Providencia

作　　者：马咏琪 张引弟 管文平 漆文瑞 姜云鹏 安亮嘉 王佳丽[1] 孙丽坤 MA Yongqi;ZHANG Yindi;GUAN Wenping;QI Wenrui;JIANG Yunpeng;AN Liangjia;WANG Jiali;SUN Likun(College of Animal Science and Technology,Gansu Agricultural University,Lanzhou 730070,Gansu,China)

机构地区：[1]甘肃农业大学动物科学技术学院,甘肃兰州730070

出　　处：《微生物学通报》2024年第11期4485-4501,共17页Microbiology China

基　　金：国家自然科学基金(32160756);甘肃农业大学“伏羲杰出人才”培育计划(GAUfx-04J03);甘肃农业大学青年研究生导师扶持计划专项(06190301)。

摘　　要：【背景】近年来,随着畜禽养殖规模的扩大,产生大量富含重金属离子的养殖污水,导致传统脱氮技术受到限制,降低污水脱氮效率。【目的】从污水处理厂污水和污泥中分离筛选耐重金属异养硝化-好氧反硝化细菌,研究其脱氮效率。【方法】通过菌落和细胞形态特征观察、16S rRNA基因序列鉴定菌种。分别以NH_(4)^(+)-N、NO_(3)^(-)-N、NO_(2)^(-)-N为唯一氮源考察菌株的硝化及反硝化性能,并考察在重金属(Cu、Zn、Cd、Cr、Pb)存在下菌株的氨氮去除能力。【结果】从污水和污泥中筛选出2株异养硝化-好氧反硝化菌WS-A和WH-K,经鉴定为普罗维登斯菌属(Providencia)。菌株WS-A、WH-K均能在以(NH_(4))_(2)SO_(4)、NaNO_(3)、NaNO_(2)为唯一氮源的培养基中生长,并且48 h内NH_(4)^(+)-N去除率为84.93%和84.48%,好氧反硝化作用NO_(3)^(-)-N的去除率分别为82.5%和86.7%,NO_(2)^(-)-N去除率分别为93.60%和93.84%。100 mg/L Zn^(2+)胁迫下菌株WS-A、WH-K氨氮去除率达80%以上,1000 mg/L的Cu^(2+)和80 mg/L Cr^(3+)、Cd^(2+)、Pb^(2+)胁迫下菌株WS-A、WH-K氨氮去除率为56%-77%。【结论】筛选出2株在5种重金属离子胁迫下仍表现良好脱氮性能的异养硝化好氧反硝化(heterotrophic nitrifying-aerobic denitrifying,HNAD)菌,初步探测了菌株的重金属耐受性,以便更好地为实际应用提供技术指导。[Background]In recent years,with the expansion of the animal farming scale,a large amount of breeding sewage rich in heavy metal ions is produced.The conventional nitrogen removal technologies have limitations in treating such sewage,demonstrating reduced nitrogen removal efficiency.[Objective]To isolate and screen heavy metal-tolerant heterotrophic nitrifying-aerobic denitrifying bacteria from sewage and sludge of a sewage treatment plant and study the nitrogen removal efficiency of the isolates.[Methods]We identified the strains by observing the morphological characteristics of colonies and cells and analyzing the 16S rRNA gene sequences.With NH_(4)^(+)-N,NO_(3)^(−)-N,and NO_(2)^(−)-N as the only nitrogen sources,the nitrification and denitrification performance of the strains,as well as the removal capacity of ammonia nitrogen in the presence of heavy metals(Cu,Zn,Cd,Cr,and Pb),was investigated.[Results]Two strains of heterotrophic nitrifying-aerobic denitrifying bacteria were isolated from sewage and sludge,identified as Providencia sp.,and named WS-A and WH-K.Both WS-A and WH-K could grow in the media with(NH_(4))_(2)SO_(4),NaNO_(3),or NaNO_(2)as the only nitrogen source,with the NH_(4)^(+)-N removal rates of 84.93%and 84.48%within 48 h,the NO_(3)^(−)-N removal rates of 82.5%and 86.7%,and the NO_(2)^(−)-N removal rates of 93.60%and 93.84%,respectively.WS-A and WH-K showcased the ammonia nitrogen removal rate more than 80%in the presence of 100 mg/L Zn^(2+)and the ammonia nitrogen removal rate within the range of 56%to 77%in the presence of 1000 mg/L Cu^(2+)or 80 mg/L Cr^(3+),Cd^(2+),and Pb^(2+).[Conclusion]We screened out two strains of heterotrophic nitrifying-aerobic denitrifying bacteria showing good nitrogen removal performance under the stress of five heavy metal ions and examined their heavy metal tolerance.The findings provide technical guidance for practical application.

关 键 词：异养硝化-好氧反硝化细菌 重金属抗性 脱氮性能 普罗维登斯菌 

分 类 号：X172[环境科学与工程—环境科学]