title: Microbial decolorization of azo dyes by Proteus mirabilis.
abstract: A bacterium identified as Proteus mirabilis was isolated from acclimated sludge from a dyeing wastewater treatment plant. This strain rapidly decolorized a deep red azo dye solution (RED RBN). Features of the decolorizing process related to biodegradation and biosorption were also studied. Although P. mirabilis displayed good growth in shake culture, color removal was best in anoxic static cultures. For color removal, the optimal pH and temperature were 6.5-7.5 and 30-35 degrees C, respectively. The organism exhibited a remarkable color removal capability, even at a high concentration of azo dye. More than 95% of azo dye was reduced within 20 h at a dye concentration of 1.0 g L-1. Decolorization appears to proceed primarily by enzymatic reduction associated with a minor portion, 13-17%, of biosorption to inactivated microbial cells.
authors.affiliation: Department of Chemical Engineering, National Tsing Hua University, Hsinchu, Taiwan.
authors.forename: K C
authors.initials: KC
authors.lastname: Chen
authors.forename: W T
authors.initials: WT
authors.lastname: Huang
authors.forename: J Y
authors.initials: JY
authors.lastname: Wu
authors.forename: J Y
authors.initials: JY
authors.lastname: Houng
mesh_terms: D001391:Azo Compounds / Q000378:metabolism*; D001673:Biodegradation, Environmental; D003116:Color; D004396:Coloring Agents / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D011513:Proteus mirabilis / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D014874:Water Pollutants, Chemical