The effect of humic acids on biodegradation of polycyclic aromatic hydrocarbons depends on the exposure regime

Tejeda-Agredano, M.C.; Mayer, Philipp; Ortega‐Calvo, José‐Julio

doi:10.1016/j.envpol.2013.09.031

Cited by 92 publications

(38 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Humic acids were collected from a soil sample taken from the Doñana National Park in Huelva, Spain. A solution of humic acids was prepared in 1 M NaOH, with a final concentration of 0.1% (w/v), and the pH was adjusted to 6 using HCl (Tejeda-Agredano et al, 2014). This solution of humic acids was also saturated with PAHs to test its effect on zoospore taxis.…”

Section: Chemical Effectors and Preparationsmentioning

confidence: 99%

Development of eukaryotic zoospores within polycyclic aromatic hydrocarbon (PAH)-polluted environments: A set of behaviors that are relevant for bioremediation

Sungthong

West

Cantos

et al. 2015

Science of The Total Environment

View full text Add to dashboard Cite

In this study, we assessed the development (formation, taxis and settlement) of eukaryotic zoospores under different regimes of exposure to polycyclic aromatic hydrocarbons (PAHs), which imitated environmental scenarios of pollution and bioremediation. With this aim, we used an oomycete, Pythium aphanidermatum, as a source of zoospores and two PAH-degrading bacteria (Mycobacterium gilvum VM552 and Pseudomonas putida G7). The oomycete and both bacteria were not antagonistic, and zoospore formation was diminished only in the presence of the highest bacterial cell density (10 8-10 10 colony-forming units mL-1). A negative influence of PAHs on zoospore formation and taxis was observed when PAHs were exposed in combination with organic solutions and polar solvents. Co-exposure of PAHs with non-polar solvents [hexadecane (HD) and 2,2,4,4,6,8,8-heptamethylnonane (HMN)] did not affect zoospore settlement at the interfaces of the organic solvents and water. However, zoospores settled and created mycelial networks only at HD-water interfaces. Both bacteria diminished the toxic influence of PAHs on zoospore formation and taxis, and they did not interrupt zoospore settlement. The results suggest that zoospore development could be applicable for toxicity assessment of PAHs and enhancement of their bioavailability. Microbial interactions during both swimming modes and community formation at pollutant interfaces were revealed as major factors that have potential relevance to bioremediation.

show abstract

Section: Chemical Effectors and Preparationsmentioning

confidence: 99%

Development of eukaryotic zoospores within polycyclic aromatic hydrocarbon (PAH)-polluted environments: A set of behaviors that are relevant for bioremediation

Sungthong

West

Cantos

et al. 2015

Science of The Total Environment

View full text Add to dashboard Cite

show abstract

“…DOM in soil is a mixture or continuum of organic molecules with different structures and molecular weights. In view of its diverse composition, DOM was regarded as part of bio-stimulation strategies to accelerate the biodegradation of PAHs [9,32,33] through its various compounds by influencing either the PAHs bioavailability or the bacterial process. Toyama (2011) [34] proved that the phenolic compounds of Phragmites australis root exudates acted as a carbon source supporting growth and induced benzo[a]pyrene-degrading activity of the a Mycobacterium strain.…”

Section: Introductionmentioning

confidence: 99%

Effects of dissolved organic matter derived from forest leaf litter on biodegradation of phenanthrene in aqueous phase

Cai

Yang

Wang

et al. 2017

Journal of Hazardous Materials

View full text Add to dashboard Cite

Dissolved organic matter (DOM) released from forest leaf litter is potentially effective for the degradation of polycyclic aromatic hydrocarbons (PAHs), yet the inherent mechanism remains insufficiently elucidated. In this study, we investigated the effects of DOM derived from Pinus elliottii and Schima superba leaf litter on the degradation of phenanthrene by the phenanthrene degrading bacterium Sphingobium sp. Phe-1. DOM from different origins and at a large range of concentrations enhanced the degradation rate of phenanthrene. DOM derived from P. elliottii leaf litter decomposed for 12 months used at a concentration of 100mg/L yielded the highest degradation rate (16.9% in 36h) and shortened the degradation time from 48h to 24h. Changes in the composition of DOM during degradation as measured by EEMs-FRI showed that proteins and tyrosine in the DOM supplied readily available nutrients that stimulated biological activity of Phe-1, increasing its growth rate and catechol 2,3-dioxygenase activity. Simultaneously, fulvic acid and humic acid in the DOM enhanced phenanthrene bioavailability by increasing the solubility and mass transfer of phenanthrene, enhancing the uptake kinetics of Phe-1, and increasing the bacteria's direct access to DOM-associated phenanthrene. Humic acid was co-metabolized by Phe-1, resulting in further stimulation of phenanthrene degradation.

show abstract

“…29 Also, a DO concentration as low as 0.034 mg L -1 has no influence on alkane biodegradation in sediment microcosms. 29 A possible role of mycelia in the production of dissolved organic carbon (DOC), which could have enhanced the biodegradation of hydrocarbons by increasing their partitioning rates from the NAPL to the aqueous phase, driven by sorption to dissolved macromolecules, 8,30 was also examined. The concentration of DOC was determined in assays that simulated the conditions during the mineralization experiments but without the NAPL and the bacterium (SI Figure S5).…”

Section: Roles Of Dissolved Oxygen and Dissolved Organic Carbon Becamentioning

confidence: 99%

“…Hydrophobic organic pollutants (e.g., polycyclic aromatic hydrocarbons (PAHs)), due to their low aqueous concentrations, often exhibit low bioavailability, which limits the metabolic activities and affects the community structures of pollutant-degrading microorganisms. [1][2][3][4][5][6][7][8] Examples of chemicals with restricted bioavailability include PAHs sorbed to natural organic matter and associated with non-aqueous phase liquids (NAPLs), e.g., crude oil and lubricants, matrices in which these chemicals show a reduced chemical activity. [4][5][6][7] Recent attempts to enhance the bioavailability and biodegradation of PAHs provided new insights into low-risk ecological approaches to optimizing bioremediation.…”

Section: Introductionmentioning

confidence: 99%

“…6 One approach is the exploitation of natural chemical enhancers (e.g., biosurfactants and plant root exudates) to accelerate the partitioning rate of PAHs from NAPLs or boost the tactic responses of PAH-degrading bacteria toward distant pollutant sources. [2][3][4][7][8][9] Additionally, improvements in pollutant bioavailability using mycelial networks formed by eukaryotic microbes (e.g., fungi and oomycetes) have recently been proposed as promising biological enhancers for facilitating the transport of PAH-degrading bacteria and PAHs, leading to increased rates of biodegradation. [10][11][12][13] Two conceptual applications of mycelial networks are considered in the bioremediation of PAH-polluted scenarios.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Mycelium-Enhanced Bacterial Degradation of Organic Pollutants under Bioavailability Restrictions

Sungthong

Tauler

Grifoll

et al. 2017

Environ. Sci. Technol.

View full text Add to dashboard Cite

This work examines the role of mycelia in enhancing the degradation by attached bacteria of organic pollutants that have poor bioavailability. Two oomycetes, Pythium oligandrum and Pythium aphanidermatum, were selected as producers of mycelial networks, while Mycobacterium gilvum VM552 served as a model polycyclic aromatic hydrocarbon (PAH) degrading bacterium. The experiments consisted of bacterial cultures exposed to a nondisturbed nonaqueous phase liquid (NAPL) layer containing a heavy fuel spiked with C-labeled phenanthrene that were incubated in the presence or absence of the mycelia of the oomycetes in both shaking and static conditions. At the end of the incubation, the changes in the total alkane and PAH contents in the NAPL residue were quantified. The results revealed that with shaking and the absence of mycelia, the strain VM552 grew by utilizing the bulk of alkanes and PAHs in the fuel; however, biofilm formation was incipient and phenanthrene was mineralized following zero-order kinetics, due to bioavailability limitations. The addition of mycelia favored biofilm formation and dramatically enhanced the mineralization of phenanthrene, up to 30 times greater than the rate without mycelia, possibly by providing a physical support to bacterial colonization and by supplying nutrients at the NAPL/water interface. The results in the static condition were very different because the bacterial strain alone degraded phenanthrene with sigmoidal kinetics but could not degrade alkanes or the bulk of PAHs. We suggest that bacteria/oomycete interactions should be considered not only in the design of new inoculants in bioremediation but also in biodegradation assessments of chemicals present in natural environments.

show abstract

The effect of humic acids on biodegradation of polycyclic aromatic hydrocarbons depends on the exposure regime

Cited by 92 publications

References 29 publications

Development of eukaryotic zoospores within polycyclic aromatic hydrocarbon (PAH)-polluted environments: A set of behaviors that are relevant for bioremediation

Development of eukaryotic zoospores within polycyclic aromatic hydrocarbon (PAH)-polluted environments: A set of behaviors that are relevant for bioremediation

Effects of dissolved organic matter derived from forest leaf litter on biodegradation of phenanthrene in aqueous phase

Mycelium-Enhanced Bacterial Degradation of Organic Pollutants under Bioavailability Restrictions

Contact Info

Product

Resources

About