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Updated: Aug 6, 2026
09:39
Physical, Chemical and Biological Characterization of Six Biochars Produced for the Remediation of Contaminated Sites
Published on: November 28, 2014
Low effect of phenanthrene bioaccessibility on its biodegradation in diffusely contaminated soil
M Crampon1, A Cébron2, F Portet-Koltalo3
1COBRA UMR CNRS 6014, Université de Rouen-Normandie, 55 rue saint Germain, 27000 Evreux, France; Laboratoire de Microbiologie Signaux et Microenvironnement, EA 4312, Université de Rouen, 76821 Mont Saint Aignan, France.
Environmental Pollution (Barking, Essex : 1987)
|April 10, 2017
Summary
This study investigated phenanthrene (PHE) biodegradation in soil. Increasing PHE bioaccessibility with biosurfactants had minimal impact on degradation rates or microbial communities, suggesting bioaccessibility is not the primary limiting factor.
Area of Science:
- Environmental Science
- Microbiology
- Soil Science
Background:
- Polycyclic Aromatic Hydrocarbons (PAHs) like phenanthrene (PHE) are persistent soil contaminants.
- Understanding factors influencing PHE biodegradation is crucial for soil remediation.
- Bioaccessibility, the fraction of a contaminant available for uptake and degradation, is a key consideration.
Purpose of the Study:
- To assess the role of bioaccessibility in phenanthrene (PHE) biodegradation in contaminated soils.
- To investigate the impact of biosurfactants on PHE sorption, desorption, and degradation.
- To identify PHE-degrading bacterial communities and their response to enhanced bioaccessibility.
Main Methods:
- Determined PHE dissipation rates and sorption/desorption isotherms in two contrasting soils (PPY and Pv).
- Utilized 13C-labeled PHE with stable isotope probing (DNA-SIP) and 16S rRNA gene pyrosequencing to analyze microbial communities.
- Applied rhamnolipids (biosurfactants) to assess their effect on PHE bioaccessibility and degradation.
Main Results:
- PHE dissipation was faster in Pv soil than PPY soil, despite similar sorption isotherms.
- Rhamnolipid addition increased PHE desorption and potential bioaccessibility but did not significantly alter degradation rates.
- Betaproteobacteria were dominant PHE degraders in Pv soil; diverse bacteria (Alpha-, Beta-, Gammaproteobacteria, Actinobacteria) degraded PHE in PPY soil.
- Biosurfactant amendment did not significantly impact PHE degradation rates or the identity of degrading bacteria.
Conclusions:
- Enhanced PHE bioaccessibility through biosurfactant application has a limited effect on its biodegradation rate.
- Microbial community structure and function involved in PHE degradation were not significantly altered by increased bioaccessibility.
- Physico-chemical properties of the soil, rather than bioaccessibility alone, may be more critical for PHE biodegradation.
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