title: Identification and characteristics of a novel salt-tolerant Exiguobacterium sp. for azo dyes decolorization.
abstract: A salt-tolerant bacterium was isolated from the surface soil of a pharmaceutical factory, which could efficiently decolorize azo dyes. The strain was identified as Exiguobacterium sp. according to its morphological characteristics and 16S rRNA gene sequence analysis. Decolorization of X-3B with resting cells of this strain, which were catalyzed by redox mediator (anthraquinone), was studied, and the conditions were optimized. For color removal and cells growth, the optimal inoculation amount, pH, temperature, salinity, and metal ions were 6% (v/v), 5.4-7.0, 30-40 degrees C, 15% (w/v) NaCl, and 1 mmol L(-1) Mg(2+) or Ca(2+), respectively. It was exhibited that decolorization process proceeded primarily by enzymatic reduction associated with a minor portion of bio-adsorption to inactivated microbial cells. Anthraquinone could really accelerate the decolorization of X-3B under the optimal conditions.
authors.affiliation: School of Environmental and Biological Science and Technology, Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), Dalian University of Technology, Dalian, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Tan
authors.forename: Yuan-yuan
authors.initials: YY
authors.lastname: Qu
authors.forename: Ji-ti
authors.initials: JT
authors.lastname: Zhou
authors.forename: Ang
authors.initials: A
authors.lastname: Li
authors.forename: Min
authors.initials: M
authors.lastname: Gou
mesh_terms: D056449:Bacillales / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D001673:Biodegradation, Environmental; D004396:Coloring Agents / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D054712:Salinity; D012965:Sodium Chloride / Q000494:pharmacology; D013696:Temperature
chemical_list: D004396:Coloring Agents; D012336:RNA, Ribosomal, 16S; D012965:Sodium Chloride