Direct ammonium oxidation to nitrogen gas (Dirammox) in Alcaligenes strain HO-1: The electrode role  

作　　者：Narcís Pous Lluis Baneras Philippe F-XCorvini Shuang-Jiang Liu Sebastia Puig 

机构地区：[1]Laboratory of Chemical and Environmental Engineering(LEQUiA),Institute of the Environment,University of Girona,Carrer Maria Aurelia Capmany,69,E-17003,Girona,Spain [2]Group of Environmental Microbial Ecology,Institute of Aquatic Ecology,University of Girona,C/Maria Aurelia Capmany,40,E-17003,Girona,Spain [3]School of Life Sciences,University of Applied Sciences and Arts Northwestern Switzerland,Muttenz,4132,Switzerland [4]State Key Laboratory of Microbial Resource at Institute of Microbiology,Chinese Academy of Sciences,Beijing,100101,China

出　　处：《Environmental Science and Ecotechnology》2023年第3期121-127,共7页环境科学与生态技术（英文）

基　　金：funded through the European Union's Horizon 2020 project ELECTRA[no.826244];National Nature Science Foundation of China(grant no.31861133002);S.P is a Serra Húnter Fellow(UdGAG-575);acknowledges the funding from the ICREA Academia award.LEQUiA[2021-SGR-01352]and Ecoaqua[2021-SGR-01142]have been recognized as consolidated research groups by the Catalan Government.

摘　　要：It has been recently suggested that Alcaligenes use a previously unknown pathway to convert ammonium into dinitrogen gas(Dirammox)via hydroxylamine(NH2OH).This fact alone already implies a significant decrease in the aeration requirements for the process,but the process would still be dependent on external aeration.This work studied the potential use of a polarised electrode as an electron acceptor for ammonium oxidation using the recently described Alcaligenes strain HO-1 as a model heterotrophic nitrifier.Results indicated that Alcaligenes strain HO-1 requires aeration for metabolism,a requirement that cannot be replaced for a polarised electrode alone.However,concomitant elimination of succinate and ammonium was observed when operating a previously grown Alcaligenes strain HO-1 culture in the presence of a polarised electrode and without aeration.The usage of a polarised electrode together with aeration did not increase the succinate nor the nitrogen removal rates observed with aeration alone.However,current density generation was observed along a feeding batch test representing an electron share of 3%of the ammonium removed in the presence of aeration and 16%without aeration.Additional tests suggested that hydroxylamine oxidation to dinitrogen gas could have a relevant role in the electron discharge onto the anode.Therefore,the presence of a polarised electrode supported the metabolic functions of Alcaligenes strain HO-1 on the simultaneous oxidation of succinate and ammonium.

关 键 词：Bioelectrochemical systems Electroactive bacteria Microbial electrochemical technologies NITRIFICATION Nitrogen removal 

分 类 号：X703[环境科学与工程—环境工程]