Variovorax sp.-mediated biodegradation of the phenyl urea herbicide linuron at micropollutant concentrations and effects of natural dissolved organic matter as supplementary carbon source

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• 作者：Benjamin Horemans (1)
  Johanna Vandermaesen (1)
  Lynn Vanhaecke (2)
  Erik Smolders (1)
  Dirk Springael (1)
  
• 关键词：Biodegradation ; Dissolved organic matter ; Micropollutants ; Variovorax ; Linuron
• 刊名：Applied Microbiology and Biotechnology
• 出版年：2013
• 出版时间：November 2013
• 年：2013
• 卷：97
• 期：22
• 页码：9837-9846
• 全文大小：
• 作者单位：Benjamin Horemans (1)
  Johanna Vandermaesen (1)
  Lynn Vanhaecke (2)
  Erik Smolders (1)
  Dirk Springael (1)
  
  1. Division of Soil and Water Management, Department of Earth and Environmental Sciences, Faculty of Bioscience Engineering, KU Leuven, Kasteelpark Arenberg 20, 3001, Leuven, Belgium
  2. Research Group Veterinary Public Health and Zoonoses, Veterinary Public Health and Food Safety-Lab. Chemical Analysis, Ghent University, Ghent, Belgium
  
• ISSN：1432-0614

文摘

In nature, pesticides are often present as micropollutants with concentrations too low for efficient biodegradation and growth of heterotrophic pollutant-degrading bacteria. Instead, organic carbon present in environmental dissolved organic matter (eDOM) constitutes the main carbon source in nature. Information on how natural organic carbon affects degradation of pollutants and micropollutants, in particular, is however poor. Linuron-degrading Variovorax sp. strains SRS16, WDL1, and PBLH6 and a triple-species bacterial consortium, from which WDL1 originated, were examined for their ability to degrade linuron at micropollutant concentrations and the effect hereon of different eDOM formulations of varying biodegradability as supplementary C-source was explored. Individual strains and the consortium degraded linuron at initial concentrations as low as 1L1 till concentrations below 4ngL1. Degradation kinetics differed among strains with rates that differed up to 70-fold at the lowest linuron concentrations and with lag phases ranging from 0 to 7days. Linuron biodegradation by the individual strains was inhibited by an easily biodegradable compound such as citrate but stimulated by eDOM at a linuron concentration of 10mgL1. Effects were strongly reduced or became non-existent at micropollutant linuron concentrations. Effects of eDOM on degradation at 10mgL1 linuron by WDL1 were reduced when WDL1 was incubated together with its original consortium members. This is the first report on eDOM effects on degradation of pesticides at micropollutant concentrations and indicates these effects are limited and depend on linuron and eDOM concentrations, eDOM quality, and the bacterial culture.