title: Nitrate-reducing, sulfide-oxidizing bacteria as microbial oxidants for rapid biological sulfide removal.
abstract: The emission of hydrogen sulfide into the atmosphere of sewer systems induces the biological production of sulfuric acid, causing severe concrete corrosion. As a possible preventive solution, a microbial consortium of nitrate-reducing, sulfide-oxidizing bacteria (NR-SOB) was enriched in a continuously stirred tank reactor in order to develop a biological technique for the removal of dissolved sulfide. The consortium, dominated by Arcobacter sp., was capable of removing 99% of sulfide. Stable isotope fractioning of the sulfide indicated that the oxidation was a biological process. The capacity of the NR-SOB consortium for rapid removal of sulfide was demonstrated by using it as an inoculum in synthetic and real sewage. Removal rates up to 52 mg sulfide-S g VSS(-1) h(-1) were achieved, to our knowledge the highest removal rate reported so far for freshwater species in the absence of molecular oxygen. Further long-term incubation experiments revealed the capacity of the bacteria to oxidize sulfide without the presence of nitrate, suggesting that an oxidized redox reserve is present in the culture.
authors.affiliation: Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Ghent, Belgium.
authors.forename: Bart
authors.initials: B
authors.lastname: De Gusseme
authors.forename: Peter
authors.initials: P
authors.lastname: De Schryver
authors.forename: Michaël
authors.initials: M
authors.lastname: De Cooman
authors.forename: Kim
authors.initials: K
authors.lastname: Verbeken
authors.forename: Pascal
authors.initials: P
authors.lastname: Boeckx
authors.forename: Willy
authors.initials: W
authors.lastname: Verstraete
authors.forename: Nico
authors.initials: N
authors.lastname: Boon
mesh_terms: D020640:Arcobacter / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D001421:Bacteria, Anaerobic / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods; D003470:Culture Media; D017753:Ecosystem; D006862:Hydrogen Sulfide / Q000378:metabolism; D008969:Molecular Sequence Data; D009566:Nitrates / Q000378:metabolism*; D016877:Oxidants / Q000378:metabolism*; D010084:Oxidation-Reduction; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000382:microbiology; D013440:Sulfides / Q000378:metabolism*; D013997:Time Factors
chemical_list: D003470:Culture Media; D009566:Nitrates; D016877:Oxidants; D012722:Sewage; D013440:Sulfides; D006862:Hydrogen Sulfide