Bioelectrochemically-assisted degradation of chloroform by a co-culture of Dehalobacter and Dehalobacterium
Fernández-Verdejo, David (Universitat Autònoma de Barcelona. Departament d'Enginyeria Química, Biològica i Ambiental)
Cortés Garmendia, M. Pilar (Universitat Autònoma de Barcelona. Departament de Genètica i de Microbiologia)
Guisasola, Albert (Universitat Autònoma de Barcelona. Departament d'Enginyeria Química, Biològica i Ambiental)
Blánquez Cano, Paqui (Universitat Autònoma de Barcelona. Departament d'Enginyeria Química, Biològica i Ambiental)
Marco Urrea, Ernest (Universitat Autònoma de Barcelona. Departament d'Enginyeria Química, Biològica i Ambiental)

Date:	2022
Abstract:	Using bioelectrochemical systems (BESs) to provide electrochemically generated hydrogen is a promising technology to provide electron donors for reductive dechlorination by organohalide-respiring bacteria. In this study, we inoculated two syntrophic dechlorinating cultures containing Dehalobacter and Dehalobacterium to sequentially transform chloroform (CF) to acetate in a BES using a graphite fiber brush as the electrode. In this co-culture, Dehalobacter transformed CF to stoichiometric amounts of dichloromethane (DCM) via organohalide respiration, whereas the Dehalobacterium -containing culture converted DCM to acetate via fermentation. BES were initially inoculated with Dehalobacter, and sequential cathodic potentials of −0. 6, −0. 7, and −0. 8 V were poised after consuming three CF doses (500 μM) per each potential during a time-span of 83 days. At the end of this period, the accumulated DCM was degraded in the following seven days after the inoculation of Dehalobacterium. At this point, four consecutive amendments of CF at increasing concentrations of 200, 400, 600, and 800 μM were sequentially transformed by the combined degradation activity of Dehalobacter and Dehalobacterium. The Dehalobacter 16S rRNA gene copies increased four orders of magnitude during the whole period. The coulombic efficiencies associated with the degradation of CF reached values > 60% at a cathodic potential of −0. 8 V when the degradation rate of CF achieved the highest values. This study shows the advantages of combining syntrophic bacteria to fully detoxify chlorinated compounds in BESs and further expands the use of this technology for treating water bodies impacted with pollutants.
Grants:	Agencia Estatal de Investigación CTM2017-91879-EXP Agencia Estatal de Investigación PID2019-103989RB-100
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial i la comunicació pública de l'obra, sempre que no sigui amb finalitats comercials, i sempre que es reconegui l'autoria de l'obra original. No es permet la creació d'obres derivades.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Dehalobacter ; Dehalobacterium ; Chloroform ; Dichloromethane ; Bioelectrochemistry ; Bioremediation
Published in:	Environmental Science and Ecotechnology, Vol. 12 (October 2022) , art 100199, ISSN 2666-4984

DOI: 10.1016/j.ese.2022.100199
PMID: 36157346

6 p, 625.7 KB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Engineering > GENOCOV
Articles > Research articles
Articles > Published articles