title: Isolation and characterization of Sphingomonas sp. Y2 capable of high-efficiency degradation of nonylphenol polyethoxylates in wastewater.
abstract: Nonylphenol polyethoxylates (NPEOs), although banned for decades, are still widely used in manufactories and thus affect human lives. In this study, a highly efficient NPEO-degrading bacterium, Sphingomonas sp. Y2, was isolated from sewage sludge by enrichment culture. Strain Y2 ensured the complete removal of NPEO in 48 h and degraded 99.2 % NPEO (1,000 mg L(-1)) within 30 h at a specific growth rate of 0.73 h(-1) in minimum salt medium. To date, this degradation efficiency is the highest reported for NPEO metabolism by a pure bacterium under this condition. Furthermore, the application of this bacterium to wastewater treatment demonstrated that it metabolized 98.5 % NPEO (1,000 mg L(-1)) within 5 days with a specific growth rate of 2.03 day(-1). The degradation intermediates, identified as nonylphenol, short-chain NPEOs and short-chain nonylphenol polyethoxycarboxylates by high-performance liquid chromatography and gas chromatography-mass spectrometry, indicated the sequential exo-cleavage of the EO chain. Additionally, the enzymes involved in the biodegradation were inducible rather than constitutive. Considering that strain Y2 exhibits prominent biodegradation advantages in industrial wastewater treatment, it might serve as a promising potential candidate for in situ bioremediation of contamination by NPEOs and other structurally similar compounds.
authors.affiliation: Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China.
authors.forename: Naling
authors.initials: N
authors.lastname: Bai
authors.affiliation: Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Wang
authors.affiliation: Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China.
authors.forename: Rexiding
authors.initials: R
authors.lastname: Abuduaini
authors.affiliation: Institute of Genetics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China. xufenzhu@zju.edu.cn.
authors.forename: Xufen
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China. yhzhao225@zju.edu.cn.
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D001673:Biodegradation, Environmental; D002851:Chromatography, High Pressure Liquid; D008401:Gas Chromatography-Mass Spectrometry; D010636:Phenols / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000378:metabolism*; D020578:Sphingomonas / Q000302:isolation & purification / Q000378:metabolism*; D014865:Waste Disposal, Fluid / Q000379:methods; D062065:Wastewater; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D010636:Phenols; D011092:Polyethylene Glycols; D062065:Wastewater; D014874:Water Pollutants, Chemical; C025256:nonylphenol
keywords: Biodegradation efficiency; Biodegradation pathway; Inducible enzymes; Nonylphenol polyethoxylates; Sphingomonas sp. Y2; Wastewater