title: Impact of electro-stimulation on denitrifying bacterial growth and analysis of bacterial growth kinetics using a modified Gompertz model in a bio-electrochemical denitrification reactor.
abstract: This study aimed to investigate the effect of electro-stimulation on denitrifying bacterial growth in a bio-electrochemical reactor, and the growth were modeled using modified Gompertz model under different current densities at three C/Ns. It was found that the similar optimum current density of 250mA/m2was obtained at C/N=0.75, 1.00 and 1.25, correspondingly the maximum nitrate removal efficiencies were 98.0%, 99.2% and 99.9%. Moreover, ATP content and cell membrane permeability of denitrifying bacteria were significantly increased at optimum current density. Furthermore, modified Gompertz model fitted well with the microbial growth curves, and the highest maximum growth rates (µmax) and shorter lag time were obtained at the optimum current density for all C/Ns. This study demonstrated that the modified Gompertz model could be used for describing microbial growth under different current densities and C/Ns in a bio-electrochemical denitrification reactor, and it provided an alternative for improving the performance of denitrification process.
authors.affiliation: Key Laboratory of Groundwater Circulation and Evolution (China University of Geosciences Beijing), Ministry of Education, No. 29 Xueyuan Road, Haidian District, Beijing 100083, China; School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, China.
authors.forename: Hengyuan
authors.initials: H
authors.lastname: Liu
authors.affiliation: Key Laboratory of Groundwater Circulation and Evolution (China University of Geosciences Beijing), Ministry of Education, No. 29 Xueyuan Road, Haidian District, Beijing 100083, China; School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Chen
authors.affiliation: Key Laboratory of Groundwater Circulation and Evolution (China University of Geosciences Beijing), Ministry of Education, No. 29 Xueyuan Road, Haidian District, Beijing 100083, China; School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, China. Electronic address: fengcp@cugb.edu.cn.
authors.forename: Chuanping
authors.initials: C
authors.lastname: Feng
authors.affiliation: School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Tong
authors.affiliation: State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Li
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D064751:Ammonium Compounds / Q000032:analysis; D001419:Bacteria / Q000254:growth & development*; D001426:Bacterial Proteins / Q000032:analysis; D019149:Bioreactors / Q000382:microbiology*; D058440:Denitrification; D004558:Electric Stimulation; D004560:Electricity; D004563:Electrochemistry / Q000295:instrumentation*; D007700:Kinetics; D008962:Models, Theoretical; D009566:Nitrates / Q000302:isolation & purification; D009573:Nitrites / Q000302:isolation & purification
chemical_list: D064751:Ammonium Compounds; D001426:Bacterial Proteins; D009566:Nitrates; D009573:Nitrites; D000255:Adenosine Triphosphate
keywords: Bio-electrochemical reactor; Denitrification; Electro-stimulation; Gompertz model; Microbial growth kinetics