Grantee Research Project Results
2001 Progress Report: Biosurfactant Specificity and Influence on Microbial Degradation of Hydrocarbons by Microbial Consortia in the Field
EPA Grant Number: R827132Title: Biosurfactant Specificity and Influence on Microbial Degradation of Hydrocarbons by Microbial Consortia in the Field
Investigators: Shreve, Gina S. , Finnerty, William
Institution: Wayne State University
EPA Project Officer: Aja, Hayley
Project Period: September 1, 1998 through August 31, 2001
Project Period Covered by this Report: September 1, 2000 through August 31, 2001
Project Amount: $424,689
RFA: EPA/DOE/NSF/ONR Joint Program on Bioremediation (1998) RFA Text | Recipients Lists
Research Category: Hazardous Waste/Remediation , Land and Waste Management
Objective:
The objective of this research project is to develop a comprehensive research program involving basic and applied field investigations to establish the efficacy of various classes of biosurfactants in the remediation of soils contaminated with mixed hydrocarbon wastes. The proposed research objectives are to: (1) determine the basis for the hydrocarbon specificity of biosurfactants in terms of micelle size, micelle dielectric constant, and targeting of minimal interfacial tension values for mixed micelle solutions to mixed wastes; (2) elucidate the influence of pollutant mixtures on the effectiveness of pure and mixed biosurfactant micelles upon solubilization of hydrocarbons; (3) assess hydrocarbon solubilization on the microbial degradation of target pollutants; and (4) conduct field studies to determine the role and influence of biosurfactants in the remediation of polluted target sites.
Progress Summary:
Solubilization of specific hydrocarbon classes from mixed waste components by biological surfactants in multiphase systems was examined during this period. Specifically, the ability of rhamnolipid biosurfactants to solubilize linear and branched alkane hydrocarbons, as well as mono- and polycyclic hydrocarbons from a mixed waste matrix containing trichloroethylene (TCE), was examined (see Table 1). Findings include:
(1) Thermodynamic frameworks describing synthetic surfactant physical behavior that apply to microbial biosurfactant interfacial properties.
(2) In mixed waste systems, hydrocarbon solutes compete for position in biosurfactant micelles. Solubilization patterns directly are influenced by hydrocarbon solute size and structure, with larger planar spatially constricted molecules being least soluble in surfactant systems. Preferential solubilization primarily is determined by solute molar volume and shape.
(3) Microbial biodegradation of micellar phase hydrocarbon can kinetically be described by a coupled model, including micellar solubilization, bulk phase micellar transport, microbial uptake, and biodegradation. This model was derived and applied to experimental data for Pseudomonas biosurfacant mediated biodegradation of hexadecane. Experimental data fits the proposed model well.
(4) While more water soluble hydrocarbons such as benzene, toluene, and TCE were enhanced by the micellar phase, their biodegradation rate was not enhanced.
(5) A new rhamnolipid biosurfactant was described with distinctly different interfacial tension behavior against various hydrocarbon classes.
(6) Biosurfactant enhanced desorption of alkane hydrocarbons in soil systems. Solubilized hydrocarbon was biodegraded. Surfactant solubilization enhanced the rate of microbial biodegradation in multiphase systems with complex mixtures of hydrocarbon waste.
(7) The field study conducted at the former Wurtsmith Air Force Base Strategic Environmental Research and Development Program (SERDP) site, known as the National Center for Integrated Bioremediation (NCIBRD) in Osceoda Michigan, yielded data indicating that the presence of biosurfactant in the in situ microcosms increased the observed rate of hydrocarbon reduction, thus indicating that the biosurfactant was active in promoting biodegradation in the indigenous microbial populations.
| Surfactant/Hydrocarbon System | Solubilization (mg HC/mg biosur-factant) | Interfacial Tension at the CMC (dyne/cm) | Critical MicelleConcentration | Area per Head Group (Å2/ molecule) |
| Rhamnolipid
Linear Alkane: |
(see Figure 2) | (see Figure 4) | (mg/ml) | (Å2/head group) |
| Hexadecane | .1288 | .261 | .0282 | 11.37 |
| Dodecane | 12.83 | .407 | .0085 | 11.46 |
| Monoaromatic: | ||||
| Benzene | .636 | 5.363 | .0228 | 15.32 |
| Toluene | 2.39 | 5.47 | .013 | 12.08 |
| Branched Alkane: | ||||
| Iso-octane | 6.23 | .285 | .0159 | 11.23 |
| Pristane | .32 | .025 mM | ||
|
Polycyclic Aromatic (PAH): Napthalene |
.0427 | |||
| Dyna 270 | (see Figure 3) | (see Figure 5) | (µg/ml) | (Å2/head group) |
| Linear Alkane: | ||||
| Hexadecane | 1081 | .542 | .0518 | 11.01 |
| Dodecane | 14807 | .125 | .0058 | 10.88 |
| Monoaromatic: | ||||
| Benzene | 1270 | .936 | .0434 | 13.58 |
| Toluene | 759 | .721 | .0549 | 15.65 |
| Branched Alkane: | ||||
| Iso-octane | 166.6 | .056 | .3618 | 15.21 |
| Pristane | 468 | .0204 | ||
| Polycyclic Aromatic (PAH):
Napthalene |
Future Activities:
Approximately six manuscripts are in preparation for submission to peer-reviewed scientific journals within the next academic year. The manuscripts will present the results at the Annual Progress Meeting for the Joint Program on Bioremediation in Chicago IL, November 1999. Scientists at the Michigan Department of Environmental Quality have expressed an interest in applying biosurfactant cleanup technology to brownfield sites. A suitable site and selection of a small business partner will be pursued.
Journal Articles on this Report : 5 Displayed | Download in RIS Format
| Other project views: | All 8 publications | 6 publications in selected types | All 6 journal articles |
|---|
| Type | Citation | ||
|---|---|---|---|
|
|
Finnerty W, Makulla R, Shreve GS. Characterization of a new rhamnolipid complex. I. General physiology. Canadian Journal of Microbiology. |
R827132 (2000) R827132 (2001) R827132 (Final) |
not available |
|
|
Finnerty W, Makulla R, Shreve GS. Characterization of a new rhamnolipid complex. II. Chemical and physical properties. Canadian Journal of Microbiology. |
R827132 (2000) R827132 (2001) R827132 (Final) |
not available |
|
|
Hung HC, Shreve GS. Effect of the hydrocarbon phase on interfacial and thermodynamic properties of two anionic glycolipid biosurfactants in hydrocarbon/water systems. Journal of Physical Chemistry B 2001;105(50):12596-12600. |
R827132 (2000) R827132 (2001) R827132 (Final) |
not available |
|
|
Hung HC, Potoff J, Shreve GS. Equilibrium structure of dodecylbenzyl sulfonate micelles in dodecane/water and benzene/water systems. Journal of the American Chemical Society. |
R827132 (2000) R827132 (2001) R827132 (Final) |
not available |
|
|
Sekelsky AM, Shreve GS. Kinetic model of biosurfactant enhanced hexadecane biodegradation by Pseudomonas aeruginosa. Biotechnology and Bioengineering 1999;63(4):401-409. |
R827132 (1999) R827132 (2000) R827132 (2001) R827132 (Final) |
not available |
Supplemental Keywords:
biosurfactant specificity, mixed waste solubilization, micelle characterization, biosurfactant mediated solubilization and biodegradation, non-aqueous phase liquid, NAPL, NAPL source reduction, mechanistic kinetic model, halogenated organic compound, HOC, surfactant mediated HOC transport, microbial biodegradation., RFA, Scientific Discipline, Ecosystem Protection/Environmental Exposure & Risk, Waste, Toxics, Remediation, chemical mixtures, Ecology, HAPS, Environmental Chemistry, Bioavailability, Bioremediation, biosurfactant specifity, hydrocarbon degrading, kinetic studies, microbial degradation, pollutant mixtures, hydrocarbon, soil characterization, NAPL, polychlorinated biphenyls, biodegradation, fate and transport, chemical transport, NAPLs, micelle solutionsRelevant Websites:
http://www.eng.wayne.edu/chem/faculty/12.htm Exit
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.