title: Performance of a newly isolated salt-tolerant yeast strain Pichia occidentalis G1 for degrading and detoxifying azo dyes.
abstract: A salt-tolerant yeast named G1 which could decolorize various azo dyes was recently isolated and identified as Pichia occidentalis. Systematic researches on characterization, degradation pathway, detoxification effects and enzymes analysis of this yeast were done. The results showed that the optimal metabolism and growth parameters for strain G1 were: 2.0gL-1glucose, 0.6gL-1ammonium sulfate, 0.08gL-1yeast extract, 30gL-1NaCl, 160rmin-1, 30°C and pH 5.0. More than 98% of 50mgL-1Acid Red B (ARB) could be decolorized within 16h under the optimal conditions. Additionally, strain G1 degraded and obviously detoxified ARB through a possible pathway successively consisting of decolorization, deamination/desulfonation and TCA cycle processes. Moreover, NADH-DCIP reductase was estimated as the key reductase for decolorization and ligninases including lignin peroxidase, manganese peroxidase and laccase were important oxidoreductases for further degradation of decolorization intermediates.
authors.affiliation: School of Life Science, Liaoning Normal University, Dalian 116081, China.
authors.forename: Li
authors.initials: L
authors.lastname: Song
authors.affiliation: School of Life Science, Liaoning Normal University, Dalian 116081, China.
authors.forename: Yifan
authors.initials: Y
authors.lastname: Shao
authors.affiliation: School of Life Science, Liaoning Normal University, Dalian 116081, China.
authors.forename: Shuxiang
authors.initials: S
authors.lastname: Ning
authors.affiliation: School of Life Science, Liaoning Normal University, Dalian 116081, China. Electronic address: tanliang19811210@163.com.
authors.forename: Liang
authors.initials: L
authors.lastname: Tan
mesh_terms: D001391:Azo Compounds / Q000378:metabolism; D001673:Biodegradation, Environmental; D004396:Coloring Agents / Q000737:chemistry; D010843:Pichia / Q000378:metabolism*; D012965:Sodium Chloride / Q000378:metabolism
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D012965:Sodium Chloride
keywords: Aerobic degradation and detoxification; Azo dye; Decolorization pathways; Enzyme analysis; Pichia occidentalis