title: Free Fe(3+)/Fe(2+) improved the biomass resource recovery and organic matter removal in Rhodobacter sphaeroides purification of sewage.
abstract: The enhancement in biomass production and organic matter removal of Rhodobacter sphaeroides (R. sphaeroides) through iron ions in soybean protein wastewater treatment was investigated. Different dosages of ferric ions were introduced in the reactors under light-anaerobic conditions. Free ferric and ferrous ions in wastewater were formed and their concentrations were the optimal for the growth of R. sphaeroides when the total Fe dosage was 20 mg/L. At the optimal dosage, biomass production (4000 mg/L) and protease activity improved by 50% and 48% when compared to the controls, respectively. The organic matter and protein removal reached above 90% and hydraulic retention time was shortened from 96 to 72 h. A mechanism analysis indicated that iron ions can effectively improve the adenosine triphosphate production, which may furthermore encourage the synthesis of protease and the cellular material.
authors.affiliation: a Center of Research on Life Science and Environmental Science , Harbin University of Commerce , Harbin 150075 , People's Republic of China.
authors.forename: Rijia
authors.initials: R
authors.lastname: Liu
authors.affiliation: a Center of Research on Life Science and Environmental Science , Harbin University of Commerce , Harbin 150075 , People's Republic of China.|b State Key Laboratory of Urban Water Resource and Environment , Harbin Institute of Technology , Harbin 150090 , People's Republic of China.
authors.forename: Pan
authors.initials: P
authors.lastname: Wu
authors.affiliation: a Center of Research on Life Science and Environmental Science , Harbin University of Commerce , Harbin 150075 , People's Republic of China.
authors.forename: Lang
authors.initials: L
authors.lastname: Lang
authors.affiliation: a Center of Research on Life Science and Environmental Science , Harbin University of Commerce , Harbin 150075 , People's Republic of China.
authors.forename: Changru
authors.initials: C
authors.lastname: Xu
authors.affiliation: c Department of Anesthesiology , The Third Affiliated Hospital of SunYat-Sen University , Guangzhou 510630 , People's Republic of China.
authors.forename: Yanling
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000693:Anaerobiosis; D057919:Biological Oxygen Demand Analysis; D018533:Biomass; D019149:Bioreactors; D005290:Ferric Compounds / Q000378:metabolism*; D008027:Light; D010940:Plant Proteins / Q000378:metabolism; D012242:Rhodobacter sphaeroides / Q000378:metabolism*; D012722:Sewage / Q000032:analysis*; D013025:Glycine max / Q000737:chemistry; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D005290:Ferric Compounds; D010940:Plant Proteins; D012722:Sewage
keywords: Fe3+; biomass production; free Fe3+/Fe2+; purple non-sulphur bacteria; soybean protein wastewater