title: Examination of protein degradation in continuous flow, microbial electrolysis cells treating fermentation wastewater.
abstract: Cellulose fermentation wastewaters (FWWs) contain short chain volatile fatty acids and alcohols, but they also have high concentrations of proteins. Hydrogen gas production from FWW was examined using continuous flow microbial electrolysis cells (MECs), with a focus on fate of the protein. H2 production rates were 0.49±0.05 m(3)/m(3)-d for the FWW, compared to 0.63±0.02 m(3)/m(3)-d using a synthetic wastewater containing only acetate (applied potential of 0.9 V). Total organic matter removal was 76±6% for the FWW, compared to 87±5% for acetate. The MEC effluent became relatively enriched in protein (69%) compared to that in the original FWW (19%). Protein was completely removed using higher applied voltages (1.0 or 1.2 V), but current generation was erratic due to more positive anode potentials (-113±38 mV, Eap=1.2V; -338±38 mV, 1.0 V; -0.426±4 mV, 0.9V). Bacteria on the anodes with FWW were primarily Deltaproteobacteria, while Archaea were predominantly Methanobacterium.
authors.affiliation: Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA 16802, USA; Jeju Global Research Center, Korea Institute of Energy Research, 200 Haemajihaean-ro, Gujwa-eup, Jeju 695-971, Republic of Korea.
authors.forename: Joo-Youn
authors.initials: JY
authors.lastname: Nam
authors.affiliation: Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Yates
authors.affiliation: Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA 16802, USA; Department of Biology, West Chester University of Pennsylvania, West Chester, PA 19383, USA.
authors.forename: Zehra
authors.initials: Z
authors.lastname: Zaybak
authors.affiliation: Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA 16802, USA. Electronic address: blogan@psu.edu.
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Logan
mesh_terms: D001419:Bacteria / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D019149:Bioreactors; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D017931:DNA Primers / Q000235:genetics; D004572:Electrolysis / Q000379:methods*; D005285:Fermentation; D006859:Hydrogen / Q000302:isolation & purification; D008969:Molecular Sequence Data; D059748:Proteolysis; D017422:Sequence Analysis, DNA; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry* / Q000382:microbiology
chemical_list: D017931:DNA Primers; D006859:Hydrogen; D062065:Wastewater
keywords: Carbohydrate; Fermentation; Hydrogen; Microbial electrolysis cell; Protein