title: Aerobic decolorization, degradation and detoxification of azo dyes by a newly isolated salt-tolerant yeast Scheffersomyces spartinae TLHS-SF1.
abstract: Isolation, identification and characterization of a salt-tolerant yeast capable of degrading and detoxifying azo dyes were investigated in this study. Possible degradation pathway of Acid Scarlet 3R was proposed through analyzing metabolic intermediates using UV-Vis and HPLC-MS methods. Furthermore, the Microtox test was performed to evaluate the acute toxicity of the dye before and after biodegradation. The results showed that a salt-tolerant yeast named TLHS-SF1 was isolated and identified as Scheffersomyces spartinae basing on 26S rDNA analysis. The optimal decolorization and growth parameters were: sucrose 2 g L(-1), (NH4)2SO4 0.6 g L(-1), yeast extract 0.08 g L(-1), NaCl ⩽ 30 g L(-1), 160 rmin(-1), 30 °C and pH 5.0-6.0. More than 90% of 80 mg L(-1) 3R could be decolorized within 16 h under the optimal conditions. 3R was possibly degraded successively through azo-reduction, deamination and desulfonation pathways, and its acute toxicity obviously decreased by strain TLHS-SF1.
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
authors.affiliation: School of Life Science, Liaoning Normal University, Dalian 116081, China.
authors.forename: Muyang
authors.initials: M
authors.lastname: He
authors.affiliation: School of Life Science, Liaoning Normal University, Dalian 116081, China.
authors.forename: Li
authors.initials: L
authors.lastname: Song
authors.affiliation: State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116023, China.
authors.forename: Xinmei
authors.initials: X
authors.lastname: Fu
authors.affiliation: School of Life Science, Liaoning Normal University, Dalian 116081, China.
authors.forename: Shengnan
authors.initials: S
authors.lastname: Shi
mesh_terms: D000332:Aerobiosis; D001391:Azo Compounds / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D001673:Biodegradation, Environmental; D004396:Coloring Agents / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D009282:Naphthalenesulfonates / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D004718:Saccharomycetales / Q000378:metabolism*; D012965:Sodium Chloride / Q000378:metabolism; D018508:Water Purification / Q000379:methods*
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D009282:Naphthalenesulfonates; D012965:Sodium Chloride; C576297:ponceau 4R
keywords: Aerobic degradation and detoxification; Azo dyes; Decolorization pathways; Salt-tolerant; Scheffersomyces spartinae