Biofilm formation of a bacterial consortium on linuron at micropollutant concentrations in continuous flow chambers and the impact of dissolved organic matter. Issue 1 (5th February 2014)

• Record Type: Journal Article
• Authors: Horemans, Benjamin; Hofkens, Johan; Smolders, Erik; Springael, Dirk
• Is Part Of: FEMS microbiology ecology. Volume 88:Issue 1(2014)
• Page Start: 184
• Page End: 194
• Publication Date: 2014-02-05
• Subjects: Microbial ecology -- Periodicals; Microbiology -- Periodicals; 579.17
• DOI: 10.1111/1574-6941.12280
• Languages: English
• ISSNs: 0168-6496

Abstract

<abstract abstract-type="main" id="fem12280-abs-0001"> <title>Abstract</title> <p>Bacterial multispecies biofilms are catalysts for pollutant degradation in aqueous ecosystems. Their activity in systems where xenobiotics occur as micropollutants (μg L<sup>−1</sup> level) and natural dissolved organic matter provides carbon and energy instead remains uncharacterized. Biofilm formation of a bacterial consortium consisting of the linuron‐degrading <italic>Variovorax</italic> sp. WDL1 and metabolite‐degrading strains <italic>Comamonas</italic> sp. WDL7 and <italic>Hyphomicrobium</italic> sp. WDL6 at micropollutant linuron concentrations and the impact of auxiliary carbon sources on degradation and biofilm composition were investigated. Biofilms formed at concentrations of 1000, 100, and 10 μg L<sup>−1</sup> linuron. The highest biomass, organized in mixed‐species mounds, was observed at 1000 μg L<sup>−1</sup> linuron, while at 100 and 10 μg L<sup>−1</sup>, thin layers of cells occurred. Linuron removal efficiencies decreased from <italic>c</italic>. 85% when fed with 100 and 1000 μg L<sup>−1</sup> linuron to 30% in case of 10 μg L<sup>−1</sup> linuron due to reduced specific activity. Biofilms grown on 10 μg L<sup>−1</sup> linuron were subsequently fed with easily and less degradable carbon sources in addition to 10 μg L<sup>−1</sup> linuron. Although co‐feeding with more degradable C‐sources increased biofilm biomass, linuron removal remained 30%. Calculations based on biofilm volume measurements pointed toward reduced specific activity, compensated by a higher biomass. Uncertainties about biofilm heterogeneity and cell volume can undo this explanation.</p> </abstract>