title: Decolourization of azo dyes by a newly isolatedKlebsiellasp. strain Y3, and effects of various factors on biodegradation.
abstract: In this study, we isolated and characterized a new strain ofKlebsiellasp. Y3, which was capable of decolourizing azo dyes under anaerobic conditions. The effects of physico-chemical parameters on the Methyl Red degradation by the strain were determined. The results indicated that strain Y3 exhibited a good decolourization ability in the range of pH from 4 to 9, temperature from 30 °C to 42 °C and salinity from 1% to 4%. A broad spectrum of azo dyes with different structures could be decolourized by the strain. The isolate decolourized Methyl Red, Congo Red, Orange I and Methyl Orange by almost 100% (100 mg/L) in 48 h. The culture exhibited an ability to decolourize repeated additions of dye, showing that the strain could be used for multiple cycles of biodegradation. Azo dyes at high concentrations could be tolerated and degraded by Y3. An almost complete mineralization of Methyl Red and Congo Red at the concentration of 800 mg/L was observed within 48 h. The high degradation potential of this bacterium supports its use in the treatment of industrial wastewater containing azo dyes.
authors.affiliation: Department of Microbiology, College of Life Science, Northeast Forestry University , Harbin , P. R. China.
authors.forename: Daizong
authors.initials: D
authors.lastname: Cui
authors.affiliation: Department of Microbiology, College of Life Science, Northeast Forestry University , Harbin , P. R. China.
authors.forename: Guofang
authors.initials: G
authors.lastname: Li
authors.affiliation: Department of Microbiology, College of Life Science, Northeast Forestry University , Harbin , P. R. China.
authors.forename: Min
authors.initials: M
authors.lastname: Zhao
authors.affiliation: Department of Microbiology, College of Life Science, Northeast Forestry University , Harbin , P. R. China.
authors.forename: Song
authors.initials: S
authors.lastname: Han
keywords: Klebsiella sp.; azo dyes; biodegradation; decolourization