Denitrification synergized with ANAMMOX for the anaerobic degradation of benzene: performance and microbial community structure

Abstract

To evaluate the effect of anaerobic ammonium oxidation (ANAMMOX) on benzene degradation under denitrification, a sequencing batch reactor (SBR) under denitrification synergized with ANAMMOX (SBR-DenAna) for benzene degradation was established by inoculating anaerobic ammonium-oxidizing bacteria (AnAOB) into a SBR under denitrification reactor (SBR-Den) for benzene degradation. The average rate of benzene degradation and the maximum first-order kinetic constant in SBR-DenAna were 2.34- and 1.41-fold those in SBR-Den, respectively, indicating that ANAMMOX improved the degradation of benzene under denitrification synergized with ANAMMOX. However, the average rate of benzene degradation decreased by 35% in the denitrification-ANAMMOX synergistic reactor when 10 mg N L NO was added; the rate recovered once NO was depleted, indicating that ANAMMOX might detoxify NO. Results from high-throughput sequencing analysis revealed that Azoarcus within the family Rhodocyclaceae might be associated with benzene degradation in the two SBRs. AnAOB affiliated with the family Candidatus Brocadiaceae were just detected in SBR-DenAna.

Treatment and nutrient recovery of synthetic flowback water from shale gas extraction by air‐cathode (PMo/CB) microbial desalination cells

“…The analyzed methods of COD, NH 4 + , and PO 4 3− in anodic and recovery chamber effluents, NO 3 − , NO 2 − , and pH, are referenced to the previous studies 28 . The detailed test method of nitrogen referenced to what Peng et al 29 . previously reported.…”

“…The analyzed methods of COD, NH 4 + , and PO 4 3− in anodic and recovery chamber effluents, NO 3 − , NO 2 − , and pH, are referenced to the previous studies. 28 The detailed test method of nitrogen referenced to what Peng et al 29 previously reported. The removal efficiencies of COD, NH 4 + , and PO 4 3− were calculated based on their difference between the influent and effluent concentrations in the anodic chamber.…”

Indigenous microbial communities in Albertan sediments are capable of anaerobic benzene biodegradation under methanogenic, sulfate‐reducing, nitrate‐reducing, and iron‐reducing redox conditions

“…These redox reactions were confirmed stoichiometrically, particularly in ‐reducing cultures, and revealed incomplete denitrification reactions in ‐reducing cultures. Consequently, the expected accumulation of H 2 S or in these environments may be deleterious for attenuations operating under these redox conditions, and the toxicity of these metabolites may require redress in engineered remediation programs, perhaps by the introduction of ferrous salts to react with sulfide (Firer, Friedler, & Lahav, 2008) or by coincubation with ammonium oxidizers that consume nitrite (Peng et al, 2017). Stoichiometric values of iron‐containing cultures also suggested a subset of reactions unrelated to Fe 3+ ‐reduction, suggesting that the bioavailability of the excess amorphous iron is limited and that concurrent methanogenic reactions may be taking place.…”

“…nitrite (Peng et al, 2017). Stoichiometric values of iron-containing cultures also suggested a subset of reactions unrelated to Fe 3+ -reduction, suggesting that the bioavailability of the excess amorphous iron is limited and that concurrent methanogenic reactions may be taking place.…”

Metabolic potential of the imperfect denitrifier Candidatus Desulfobacillus denitrificans in an anammox bioreactor

“…Recently, it has been reported that denitrification synergized with anammox could accelerate the anaerobic degradation of benzene, and Rhodocyclaceae bacteria might play a role in benzene degradation (Peng et al, 2017 ). Although one possible contribution of anammox bacteria could be to remove the nitrite that accumulates as a result of denitrification, benzene and metabolic intermediates such as toluene, phenol and benzoate were found to inhibit anammox activity (Peng et al, 2018 ).…”