title: A sustainable, carbon neutral methane oxidation by a partnership of methane oxidizing communities and microalgae.
abstract: Effluents of anaerobic wastewater treatment plants are saturated with methane, an effective greenhouse gas. We propose a novel approach to treat such effluents using a coculture of methane oxidizing communities and microalgae, further indicated as methalgae, which would allow microbial methane oxidation with minimal CO(2) emissions. Coculturing a methane oxidizing community with microalgae in sequence batch reactors under continuous lightning yielded a factor of about 1.6 more biomass relative to the control without microalgae. Moreover, 55% less external oxygen supply was needed to maintain the methane oxidation, as oxygen was produced in situ by the microalgae. An overall methane oxidation rate of 171±27 mg CH(4) L(-1) liquid phase d(-1) was accomplished in a semi-batch setup, while the excess CO(2) production was lower than 1mg CO(2) L(-1) d(-1). Both nitrate and ammonium were feasible nitrogen sources for the methalgae. These results show that a coculture of microalgae and methane oxidizing communities can be used to oxidize dissolved methane under O(2)-limiting conditions, which could lead to a novel treatment for dissolved methane in anaerobic effluents.
authors: Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Gent, Belgium.
authors: David
authors: D
authors: van der Ha
authors: Bert
authors: B
authors: Bundervoet
authors: Willy
authors: W
authors: Verstraete
authors: Nico
authors: N
authors: Boon
mesh_terms: D000393:Air Pollutants / Q000032:analysis / Q000378:metabolism*; D001419:Bacteria / Q000254:growth & development / Q000378:metabolism*; D057919:Biological Oxygen Demand Analysis; D002244:Carbon / Q000378:metabolism; D058572:Carbon Footprint; D003247:Conservation of Natural Resources; D008697:Methane / Q000032:analysis / Q000378:metabolism*; D058086:Microalgae / Q000254:growth & development / Q000378:metabolism*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D000393:Air Pollutants; D002244:Carbon; D008697:Methane; D010100:Oxygen