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van der Waals MJ, Plugge C, Meima-Franke M, de Waard P, Bodelier PLE, Smidt H, Gerritse J. Ethyl tert-butyl ether (EtBE) degradation by an algal-bacterial culture obtained from contaminated groundwater. WATER RESEARCH 2019; 148:314-323. [PMID: 30391860 DOI: 10.1016/j.watres.2018.10.050] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 10/16/2018] [Accepted: 10/17/2018] [Indexed: 06/08/2023]
Abstract
EtBE is a fuel oxygenate that is synthesized from (bio)ethanol and fossil-based isobutylene, and replaces the fossil-based MtBE. Biodegradation of EtBE to harmless metabolites or end products can reduce the environmental and human health risks after accidental release. In this study, an algal-bacterial culture enriched from contaminated groundwater was used to (i) assess the potential for EtBE degradation, (ii) resolve the EtBE degradation pathway and (iii) characterize the phylogenetic composition of the bacterial community involved in EtBE degradation in contaminated groundwater. In an unamended microcosm, algal growth was observed after eight weeks when exposed to a day-night light cycle. In the fed-batch reactor, oxygen produced by the algae Scenedesmus and Chlorella was used by bacteria to degrade 50 μM EtBE replenishments with a cumulative total of 1250 μM in a day/night cycle (650 lux), over a period of 913 days. The microbial community in the fed-batch reactor degraded EtBE, using a P450 monooxygenase and 2-hydroxyisobutyryl-CoA mutase, to tert-butyl alcohol (TBA), ethanol and CO2 as determined using 13C nuclear magnetic resonance spectroscopy (NMR) and gas chromatography. Stable isotope probing (SIP) with 13C6 labeled EtBE in a fed-batch vessel showed no significant difference in community profiles of the 13C and 12C enriched DNA fractions, with representatives of the families Halomonadaceae, Shewanellaceae, Rhodocyclaceae, Oxalobacteraceae, Comamonadaceae, Sphingomonadaceae, Hyphomicrobiaceae, Candidatus Moranbacteria, Omnitrophica, Anaerolineaceae, Nocardiaceae, and Blastocatellaceae. This is the first study describing micro-oxic degradation of EtBE by an algal-bacterial culture. This algal-bacterial culture has advantages compared with conventional aerobic treatments: (i) a lower risk of EtBE evaporation and (ii) no need for external oxygen supply in the presence of light. This study provides novel leads towards future possibilities to implement algal-bacterial consortia in field-scale groundwater or wastewater treatment.
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Affiliation(s)
- Marcelle J van der Waals
- Deltares, Subsurface and Groundwater Systems, Daltonlaan 600, 3584 BK, Utrecht, the Netherlands; Wageningen University & Research, Laboratory of Microbiology, Stippeneng 4, 6708 WE, Wageningen, the Netherlands.
| | - Caroline Plugge
- Wageningen University & Research, Laboratory of Microbiology, Stippeneng 4, 6708 WE, Wageningen, the Netherlands
| | - Marion Meima-Franke
- The Netherlands Institute of Ecology (NIOO-KNAW), Department of Microbial Ecology, Droevendaalsesteeg 10, 6708 PB, Wageningen, the Netherlands
| | - Pieter de Waard
- Wageningen University & Research, BioNanoTechnology, Bornse Weilanden 9, 6700 EK, Wageningen, the Netherlands
| | - Paul L E Bodelier
- The Netherlands Institute of Ecology (NIOO-KNAW), Department of Microbial Ecology, Droevendaalsesteeg 10, 6708 PB, Wageningen, the Netherlands
| | - Hauke Smidt
- Wageningen University & Research, Laboratory of Microbiology, Stippeneng 4, 6708 WE, Wageningen, the Netherlands
| | - Jan Gerritse
- Deltares, Subsurface and Groundwater Systems, Daltonlaan 600, 3584 BK, Utrecht, the Netherlands
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Hitzfeld KL, Gehre M, Richnow HH. Evaluation of the performance of high temperature conversion reactors for compound-specific oxygen stable isotope analysis. ISOTOPES IN ENVIRONMENTAL AND HEALTH STUDIES 2017; 53:116-133. [PMID: 27686404 DOI: 10.1080/10256016.2016.1215983] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 06/02/2016] [Indexed: 06/06/2023]
Abstract
In this study conversion conditions for oxygen gas chromatography high temperature conversion (HTC) isotope ratio mass spectrometry (IRMS) are characterised using qualitative mass spectrometry (IonTrap). It is shown that physical and chemical properties of a given reactor design impact HTC and thus the ability to accurately measure oxygen isotope ratios. Commercially available and custom-built tube-in-tube reactors were used to elucidate (i) by-product formation (carbon dioxide, water, small organic molecules), (ii) 2nd sources of oxygen (leakage, metal oxides, ceramic material), and (iii) required reactor conditions (conditioning, reduction, stability). The suitability of the available HTC approach for compound-specific isotope analysis of oxygen in volatile organic molecules like methyl tert-butyl ether is assessed. Main problems impeding accurate analysis are non-quantitative HTC and significant carbon dioxide by-product formation. An evaluation strategy combining mass spectrometric analysis of HTC products and IRMS 18O/16O monitoring for future method development is proposed.
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Affiliation(s)
- Kristina L Hitzfeld
- a Department of Isotope Biogeochemistry , Helmholtz-Centre for Environmental Research - UFZ , Leipzig , Germany
| | - Matthias Gehre
- a Department of Isotope Biogeochemistry , Helmholtz-Centre for Environmental Research - UFZ , Leipzig , Germany
| | - Hans-Hermann Richnow
- a Department of Isotope Biogeochemistry , Helmholtz-Centre for Environmental Research - UFZ , Leipzig , Germany
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3
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Blaser M, Conrad R. Stable carbon isotope fractionation as tracer of carbon cycling in anoxic soil ecosystems. Curr Opin Biotechnol 2016; 41:122-129. [DOI: 10.1016/j.copbio.2016.07.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 06/29/2016] [Accepted: 07/04/2016] [Indexed: 01/16/2023]
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Nijenhuis I, Richnow HH. Stable isotope fractionation concepts for characterizing biotransformation of organohalides. Curr Opin Biotechnol 2016; 41:108-113. [DOI: 10.1016/j.copbio.2016.06.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 05/23/2016] [Accepted: 06/06/2016] [Indexed: 12/11/2022]
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Wei M, Rakoczy J, Vogt C, Harnisch F, Schumann R, Richnow HH. Enhancement and monitoring of pollutant removal in a constructed wetland by microbial electrochemical technology. BIORESOURCE TECHNOLOGY 2015; 196:490-499. [PMID: 26282780 DOI: 10.1016/j.biortech.2015.07.111] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Revised: 07/27/2015] [Accepted: 07/29/2015] [Indexed: 06/04/2023]
Abstract
A bench-scale constructed wetland combined with microbial electrochemical technology (MET-CW) was run for 400days with groundwater contaminated with benzene, methyl-tert-butyl ether (MTBE), and ammonium (NH4(+)). Four vertically stacked anode modules were embedded into a sand bed and connected with a stainless steel cathode placed in an open water pond. In the zone of presence of anode modules, significantly more benzene and MTBE were removed in the MET-CW compared to the control CW without MET in the first 150 operation days. Benzene was identified as primary electron donor at the anode. Benzene removal and current densities were linearly correlated, implying the potential of the system for electrochemically monitoring benzene biodegradation. Compound-specific isotope analysis (CSIA) indicated that benzene was initially activated by monohydroxylation forming intermediates which were subsequently oxidized accompanied by extracellular electron transfer, leading to current production. NH4(+) removal was not stimulated by MET.
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Affiliation(s)
- Manman Wei
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraβe 15, 04318 Leipzig, Germany; Faculty of Natural Sciences, Hohenheim University, 70593 Stuttgart, Germany
| | - Jana Rakoczy
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraβe 15, 04318 Leipzig, Germany
| | - Carsten Vogt
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraβe 15, 04318 Leipzig, Germany.
| | - Falk Harnisch
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig, Germany
| | - Reinhard Schumann
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraβe 15, 04318 Leipzig, Germany
| | - Hans H Richnow
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraβe 15, 04318 Leipzig, Germany
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Bombach P, Nägele N, Rosell M, Richnow HH, Fischer A. Evaluation of ethyl tert-butyl ether biodegradation in a contaminated aquifer by compound-specific isotope analysis and in situ microcosms. JOURNAL OF HAZARDOUS MATERIALS 2015; 286:100-106. [PMID: 25559863 DOI: 10.1016/j.jhazmat.2014.12.028] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 12/07/2014] [Accepted: 12/17/2014] [Indexed: 06/04/2023]
Abstract
Ethyl tert-butyl ether (ETBE) is an upcoming groundwater pollutant in Europe whose environmental fate has been less investigated, thus far. In the present study, we investigated the in situ biodegradation of ETBE in a fuel-contaminated aquifer using compound-specific stable isotope analysis (CSIA), and in situ microcosms in combination with total lipid fatty acid (TLFA)-stable isotope probing (SIP). In a first field investigation, CSIA revealed insignificant carbon isotope fractionation, but low hydrogen isotope fractionation of up to +14‰ along the prevailing anoxic ETBE plume suggesting biodegradation of ETBE. Ten months later, oxygen injection was conducted to enhance the biodegradation of petroleum hydrocarbons (PH) at the field site. Within the framework of this remediation measure, in situ microcosms loaded with [(13)C6]-ETBE (BACTRAP(®)s) were exposed for 119 days in selected groundwater wells to assess the biodegradation of ETBE by TLFA-SIP under the following conditions: (i) ETBE as main contaminant; (ii) ETBE as main contaminant subjected to oxygen injection; (iii) ETBE plus other PH; (iv) ETBE plus other PH subjected to oxygen injection. Under all conditions investigated, significant (13)C-incorporation into microbial total lipid fatty acids extracted from the in situ microcosms was found, providing clear evidence of ETBE biodegradation.
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Affiliation(s)
- Petra Bombach
- UFZ - Helmholtz Centre for Environmental Research, Department of Isotope Biogeochemistry, Permoserstrasse 15, D-04318 Leipzig, Germany; Isodetect GmbH Leipzig, Deutscher Platz 5b, D-04103 Leipzig, Germany.
| | - Norbert Nägele
- Kuvier the Biotech Company S.L., Ctra. N-I, p.k. 234-P.E. INBISA 23ª, E-09001 Burgos, Spain
| | - Mònica Rosell
- UFZ - Helmholtz Centre for Environmental Research, Department of Isotope Biogeochemistry, Permoserstrasse 15, D-04318 Leipzig, Germany; Grup de Mineralogia Aplicada i Medi Ambient, Departament de Cristal·lografia, Mineralogia i Dipòsits Minerals, Facultat de Geologia, Universitat de Barcelona (UB), C/Martí i Franquès s/n, 08028 Barcelona, Spain
| | - Hans H Richnow
- UFZ - Helmholtz Centre for Environmental Research, Department of Isotope Biogeochemistry, Permoserstrasse 15, D-04318 Leipzig, Germany
| | - Anko Fischer
- Isodetect GmbH Leipzig, Deutscher Platz 5b, D-04103 Leipzig, Germany
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7
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Wu L, Yao J, Trebse P, Zhang N, Richnow HH. Compound specific isotope analysis of organophosphorus pesticides. CHEMOSPHERE 2014; 111:458-463. [PMID: 24997952 DOI: 10.1016/j.chemosphere.2014.04.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 03/26/2014] [Accepted: 04/12/2014] [Indexed: 06/03/2023]
Abstract
Compound-specific isotope analysis (CSIA) has been established as a tool to study the environmental fate of a wide range of contaminants. In this study, CSIA was developed to analyse the stable carbon isotope signatures of the widely used organophosphorus pesticides: dichlorvos, omethoate and dimethoate. The linearity of the GC-C-IRMS system was tested for target pesticides and led to an acceptable isotope composition within the uncertainty of the instrument. In order to assess the accuracy of the developed method, the effect of the evaporation procedure on measured carbon isotope composition (δ(13)C) values was studied and showed that concentration by evaporation of solvents had no significant isotope effect. The CSIA was then applied to investigate isotope fractionation of the hydrolysis and photolysis of selected pesticides. The carbon isotope fractionation of tested pesticides was quantified by the Rayleigh model, which revealed a bulk enrichment factor (ε) of -0.2±0.1‰ for hydrolysis of dichlorvos, -1.0±0.1‰ and -3.7±1.1‰ for hydrolysis and photolysis of dimethoate respectively. This study is a first step towards the application of CSIA to trace the transport and degradation of organophosphorus pesticides in the environment.
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Affiliation(s)
- Langping Wu
- School of Civil and Environmental Engineering, and National International Cooperation Based on Environment and Energy, University of Science and Technology Beijing, Xueyuan Road No. 30, Haidian District, Beijing 100083, PR China
| | - Jun Yao
- School of Civil and Environmental Engineering, and National International Cooperation Based on Environment and Energy, University of Science and Technology Beijing, Xueyuan Road No. 30, Haidian District, Beijing 100083, PR China.
| | - Polonca Trebse
- Laboratory for Environmental Research, University of Nova Gorica, Vipavska 13, Nova Gorica SI-5000, Slovenia.
| | - Ning Zhang
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 9 15, Leipzig 04318, Germany
| | - Hans H Richnow
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 9 15, Leipzig 04318, Germany
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Levchuk I, Bhatnagar A, Sillanpää M. Overview of technologies for removal of methyl tert-butyl ether (MTBE) from water. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 476-477:415-433. [PMID: 24486497 DOI: 10.1016/j.scitotenv.2014.01.037] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/09/2014] [Accepted: 01/09/2014] [Indexed: 06/03/2023]
Abstract
Wide use of methyl tert-butyl ether (MTBE) as fuel oxygenates leads to worldwide environment contamination with this compound basically due to fuel leaks from storage or pipelines. Presence of MTBE in drinking water is of high environmental and social concern. Existing methods for MTBE removal from water have a number of limitations which can be possibly overcome in the future with use of emerging technologies. This work aims to provide an updated overview of recent developments in technologies for MTBE removal from water.
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Affiliation(s)
- Irina Levchuk
- Laboratory of Green Chemistry, Department of Energy and Environmental Technology, Faculty of Technology, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli, Finland.
| | - Amit Bhatnagar
- Department of Biology and Environmental Science, Linnaeus University, SE-391 82 Kalmar, Sweden
| | - Mika Sillanpää
- Laboratory of Green Chemistry, Department of Energy and Environmental Technology, Faculty of Technology, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli, Finland
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Jammer S, Voloshenko A, Gelman F, Lev O. Chiral and isotope analyses for assessing the degradation of organic contaminants in the environment: Rayleigh dependence. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:3310-3318. [PMID: 24471759 DOI: 10.1021/es4039209] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The Rayleigh equation is frequently used to describe isotope fractionation as a function of conversion. In this article we propose to draw a parallel between isotope and enantiomeric enrichments and derive a set of conditions that allow the use of the Rayleigh approach to describe the enantiomeric enrichment-conversion dependencies. We demonstrate an implementation of the Rayleigh equation for the enantioselective enzymatic hydrolysis of Mecoprop-methyl, Dichlorprop-methyl, and dimethyl-methylsuccinate by lipases from Pseudomonas fluorescens, Pseudomonas cepacia, and Candida rugosa. The data obtained for all the studied reactions gave good fits to the Rayleigh equation, with a linear regression R(2) > 0.96. In addition to that, our analysis of four microcosm studies on the hydrolysis of the individual enantiomers of Dichloroprop methyl, Lactofen, Fenoxaprop-ethyl, and Metalaxyl reported in the literature by other research groups revealed a suitability of the Rayleigh dependence. Two dimensional plots describing the isotope fractionation versus enantiomeric enrichment are demonstrated for all studied cases. Processes not accompanied by enantiomeric enrichment (acid and base hydrolysis) and by isotope enrichment (transesterification) are demonstrated, their 2-D plots are either horizontal or vertical which can illuminate concealed degradation pathways.
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Affiliation(s)
- S Jammer
- The Casali Center of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem , Jerusalem 91904, Israel
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Bashir S, Fischer A, Nijenhuis I, Richnow HH. Enantioselective carbon stable isotope fractionation of hexachlorocyclohexane during aerobic biodegradation by Sphingobium spp. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:11432-11439. [PMID: 24007541 DOI: 10.1021/es402197s] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Carbon isotope fractionation was investigated for the biotransformation of γ- and α- hexachlorocyclohexane (HCH) as well as enantiomers of α-HCH using two aerobic bacterial strains: Sphingobium indicum strain B90A and Sphingobium japonicum strain UT26. Carbon isotope enrichment factors (ε(c)) for γ-HCH (ε(c) = -1.5 ± 0.1 ‰ and -1.7 ± 0.2 ‰) and α-HCH (ε(c) = -1.0 ± 0.2 ‰ and -1.6 ± 0.3 ‰) were similar for both aerobic strains, but lower in comparison with previously reported values for anaerobic γ- and α-HCH degradation. Isotope fractionation of α-HCH enantiomers was higher for (+) α-HCH (ε(c) = -2.4 ± 0.8 ‰ and -3.3 ± 0.8 ‰) in comparison to (-) α-HCH (ε(c) = -0.7 ± 0.2 ‰ and -1.0 ± 0.6 ‰). The microbial fractionation between the α-HCH enantiomers was quantified by the Rayleigh equation and enantiomeric fractionation factors (ε(e)) for S. indicum strain B90A and S. japonicum strain UT26 were -42 ± 16% and -22 ± 6%, respectively. The extent and range of isomer and enantiomeric carbon isotope fractionation of HCHs with Sphingobium spp. suggests that aerobic biodegradation of HCHs can be monitored in situ by compound-specific stable isotope analysis (CSIA) and enantiomer-specific isotope analysis (ESIA). In addition, enantiomeric fractionation has the potential as a complementary approach to CSIA and ESIA for assessing the biodegradation of α-HCH at contaminated field sites.
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Affiliation(s)
- Safdar Bashir
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ , Permoserstraße 15, 04318, Leipzig, Germany
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Jaekel U, Vogt C, Fischer A, Richnow HH, Musat F. Carbon and hydrogen stable isotope fractionation associated with the anaerobic degradation of propane and butane by marine sulfate-reducing bacteria. Environ Microbiol 2013; 16:130-40. [DOI: 10.1111/1462-2920.12251] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 07/30/2013] [Accepted: 08/12/2013] [Indexed: 10/26/2022]
Affiliation(s)
- Ulrike Jaekel
- Department of Microbiology; Max Planck Institute for Marine Microbiology; Bremen 28359 Germany
| | - Carsten Vogt
- Department of Isotope Biogeochemistry; Helmholtz Centre for Environmental Research -UFZ; Leipzig Germany
| | - Anko Fischer
- Department of Isotope Biogeochemistry; Helmholtz Centre for Environmental Research -UFZ; Leipzig Germany
- Isodetect GmbH; Leipzig Germany
| | - Hans-Hermann Richnow
- Department of Isotope Biogeochemistry; Helmholtz Centre for Environmental Research -UFZ; Leipzig Germany
| | - Florin Musat
- Department of Microbiology; Max Planck Institute for Marine Microbiology; Bremen 28359 Germany
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Gonzalez-Olmos R, Kopinke FD, Mackenzie K, Georgi A. Hydrophobic Fe-zeolites for removal of MTBE from water by combination of adsorption and oxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:2353-2360. [PMID: 23346998 DOI: 10.1021/es303885y] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Several zeolites were evaluated as adsorbents for the removal of MTBE from water in a screening process. It was observed that the SiO2/Al2O3 molar ratio is a decisive factor for the adsorption properties, at least in the case of ZSM5 zeolites. ZSM5 zeolites with SiO2/Al2O3 ratios >200 were found to provide the best sorption properties for MTBE. To design a combined sorption/reaction method, regeneration of the loaded zeolites by selected advanced oxidation processes (AOP) was studied: (1) Fenton treatment using H2O2 with dissolved iron salts and (2) heterogeneous Fenton-like oxidation with Fe immobilized on the zeolites. The first was ineffective in regenerating loaded zeolites. However, heterogeneous catalysis using Fe species immobilized on the zeolite by liquid ion exchange was markedly more effective. Although these hydrophobic zeolites have a low ion exchange capacity, resulting in iron loadings of ≤ 0.09 wt %, it was possible to obtain sufficiently active catalysts. Hydrophobic Fe-zeolites can therefore be regarded as promising materials for the removal of MTBE from water, since they allow the combination of efficient adsorption and oxidative degradation of MTBE by H2O2. In contrast to the homogeneous catalysis by dissolved iron ions, these heterogeneous catalysts work at near-neutral pH and can be easily reused. Fe-zeolites as adsorbents/catalysts showed a good stability in both batch and column experiments.
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Affiliation(s)
- Rafael Gonzalez-Olmos
- Helmholtz Centre for Environmental Research (UFZ) , Department of Environmental Engineering, Permoserstrasse 15, D-04318 Leipzig, Germany
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Thullner M, Fischer A, Richnow HH, Wick LY. Influence of mass transfer on stable isotope fractionation. Appl Microbiol Biotechnol 2012; 97:441-52. [PMID: 23143531 DOI: 10.1007/s00253-012-4537-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Revised: 10/19/2012] [Accepted: 10/22/2012] [Indexed: 11/27/2022]
Abstract
Biodegradation of contaminants is a common remediation strategy for subsurface environments. To monitor the success of such remediation means a quantitative assessment of biodegradation at the field scale is required. Nevertheless, the reliable quantification of the in situ biodegradation process it is still a major challenge. Compound-specific stable isotope analysis has become an established method for the qualitative analysis of biodegradation in the field and this method is also proposed for a quantitative analysis. However, to use stable isotope data to obtain quantitative information on in situ biodegradation requires among others knowledge on the influence of mass transfer processes on the observed stable isotope fractionation. This paper reviews recent findings on the influence of mass transfer processes on stable isotope fractionation and on the quantitative interpretation of isotope data. Focus will be given on small-scale mass transfer processes controlling the bioavailability of contaminants. Such bioavailability limitations are known to affect the biodegradation rate and have recently been shown to affect stable isotope fractionation, too. Theoretical as well as experimental studies addressing the link between bioavailability and stable isotope fractionation are reviewed and the implications for assessing biodegradation in the field are discussed.
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Affiliation(s)
- Martin Thullner
- Department of Environmental Microbiology, UFZ-Helmholtz Centre for Environmental Research, Permoserstr. 15, 30418 Leipzig, Germany.
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14
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Hyman M. Biodegradation of gasoline ether oxygenates. Curr Opin Biotechnol 2012; 24:443-50. [PMID: 23116604 DOI: 10.1016/j.copbio.2012.10.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 09/17/2012] [Accepted: 10/03/2012] [Indexed: 10/27/2022]
Abstract
Ether oxygenates such as methyl tertiary butyl ether (MTBE) are added to gasoline to improve fuel combustion and decrease exhaust emissions. Ether oxygenates and their tertiary alcohol metabolites are now an important group of groundwater pollutants. This review highlights recent advances in our understanding of the microorganisms, enzymes and pathways involved in both the aerobic and anaerobic biodegradation of these compounds. This review also aims to illustrate how these microbiological and biochemical studies have guided, and have helped refine, molecular and stable isotope-based analytical approaches that are increasingly being used to detect and quantify biodegradation of these compounds in contaminated environments.
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Affiliation(s)
- Michael Hyman
- Department of Microbiology, North Carolina State University, Raleigh, NC 27695, USA.
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15
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Field applicability of Compound-Specific Isotope Analysis (CSIA) for characterization and quantification of in situ contaminant degradation in aquifers. Appl Microbiol Biotechnol 2012; 94:1401-21. [PMID: 22573267 DOI: 10.1007/s00253-012-4077-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2011] [Revised: 04/03/2012] [Accepted: 04/03/2012] [Indexed: 10/28/2022]
Abstract
Microbial processes govern the fate of organic contaminants in aquifers to a major extent. Therefore, the evaluation of in situ biodegradation is essential for the implementation of Natural Attenuation (NA) concepts in groundwater management. Laboratory degradation experiments and biogeochemical approaches are often biased and provide only indirect evidence of in situ degradation potential. Compound-Specific Isotope Analysis (CSIA) is at present among the most promising tools for assessment of the in situ contaminant degradation within aquifers. One- and two-dimensional (2D) CSIA provides qualitative and quantitative information on in situ contaminant transformation; it is applicable for proving in situ degradation and characterizing degradation conditions and reaction mechanisms. However, field application of CSIA is challenging due to a number of influencing factors, namely those affecting the observed isotope fractionation during biodegradation (e.g., non-isotope-fractionating rate-limiting steps, limited bioavailability), potential isotope effects caused by processes other than biodegradation (e.g., sorption, volatilization, diffusion), as well as non-isotope-fractionating physical processes such as dispersion and dilution. This mini-review aims at guiding practical users towards the sound interpretation of CSIA field data for the characterization of in situ contaminant degradation. It focuses on the relevance of various constraints and influencing factors in CSIA field applications and provides advice on when and how to account for these constraints. We first evaluate factors that can influence isotope fractionation during biodegradation, as well as potential isotope-fractionating and non-isotope-fractionating physical processes governing observed isotope fractionation in the field. Finally, the potentials of the CSIA approach for site characterization and the proper ways to account for various constraints are illustrated by means of a comprehensive CSIA field study at the benzene, toluene, ethylbenzene, and xylene (BTEX)-contaminated site Zeitz.
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Rosell M, Gonzalez-Olmos R, Rohwerder T, Rusevova K, Georgi A, Kopinke FD, Richnow HH. Critical evaluation of the 2D-CSIA scheme for distinguishing fuel oxygenate degradation reaction mechanisms. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:4757-4766. [PMID: 22455373 DOI: 10.1021/es2036543] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Although the uniform initial hydroxylation of methyl tert-butyl ether (MTBE) and other oxygenates during aerobic biodegradation has already been proven by molecular tools, variations in carbon and hydrogen enrichment factors (ε(C) and ε(H)) have still been associated with different reaction mechanisms (McKelvie et al. Environ. Sci. Technol. 2009, 43, 2793-2799). Here, we present new laboratory-derived ε(C) and ε(H) data on the initial degradation mechanisms of MTBE, ethyl tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME) by chemical oxidation (permanganate, Fenton reagents), acid hydrolysis, and aerobic bacteria cultures (species of Aquincola, Methylibium, Gordonia, Mycobacterium, Pseudomonas, and Rhodococcus). Plotting of Δδ(2)H/ Δδ(13)C data from chemical oxidation and hydrolysis of ethers resulted in slopes (Λ values) of 22 ± 4 and between 6 and 12, respectively. With A. tertiaricarbonis L108, R. zopfii IFP 2005, and Gordonia sp. IFP 2009, ε(C) was low (<|-1|‰) and ε(H) was insignificant. Fractionation obtained with P. putida GPo1 was similar to acid hydrolysis and M. austroafricanum JOB5 and R. ruber DSM 7511 displayed Λ values previously only ascribed to anaerobic attack. The fractionation patterns rather correlate with the employment of different P450, AlkB, and other monooxygenases, likely catalyzing ether hydroxylation via different transition states. Our data questions the value of 2D-CSIA for a simple distinguishing of oxygenate biotransformation mechanisms, therefore caution and complementary tools are needed for proper interpretation of groundwater plumes at field sites.
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Affiliation(s)
- Mònica Rosell
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318 Leipzig, Germany.
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Fayolle-Guichard F, Durand J, Cheucle M, Rosell M, Michelland RJ, Tracol JP, Le Roux F, Grundman G, Atteia O, Richnow HH, Dumestre A, Benoit Y. Study of an aquifer contaminated by ethyl tert-butyl ether (ETBE): site characterization and on-site bioremediation. JOURNAL OF HAZARDOUS MATERIALS 2012; 201-202:236-243. [PMID: 22177017 DOI: 10.1016/j.jhazmat.2011.11.074] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Revised: 10/18/2011] [Accepted: 11/22/2011] [Indexed: 05/31/2023]
Abstract
Ethyl tert-butyl ether (ETBE) was detected at high concentration (300mgL(-1)) in the groundwater below a gas-station. No significant carbon neither hydrogen isotopic fractionation of ETBE was detected along the plume. ETBE and BTEX biodegradation capacities of the indigenous microflora Pz1-ETBE and of a culture (MC-IFP) composed of Rhodococcus wratislaviensis IFP 2016, Rhodococcus aetherivorans IFP 2017 and Aquincola tertiaricarbonis IFP 2003 showed that ETBE and BTEX degradation rates were in the same range (ETBE: 0.91 and 0.83 mg L(-1)h(-1) and BTEX: 0.64 and 0.82 mg L(-1)h(-1), respectively) but tert-butanol (TBA) accumulated transiently at a high level using Pz1-ETBE (74 mg L(-1)). An on-site pilot plant (2m(3)) filled with polluted groundwater and inoculated by MC-IFP, successfully degraded four successive additions of ETBE and gasoline. However, an insignificant ETBE isotopic fractionation was also accompanying this decrease which suggested the involvement of low fractionating-strains using EthB enzymes, but required of additional proofs. The ethB gene encoding a cytochrome P450 involved in ETBE biodegradation (present in R. aetherivorans IFP 2017) was monitored by quantitative real-time polymerase chain reaction (q-PCR) on DNA extracted from water sampled in the pilot plant which yield up to 5×10(6) copies of ethB gene per L(-1).
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Formation of alkenes via degradation of tert-alkyl ethers and alcohols by Aquincola tertiaricarbonis L108 and Methylibium spp. Appl Environ Microbiol 2011; 77:5981-7. [PMID: 21742915 DOI: 10.1128/aem.00093-11] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacterial degradation pathways of fuel oxygenates such as methyl tert-butyl and tert-amyl methyl ether (MTBE and TAME, respectively) have already been studied in some detail. However, many of the involved enzymes are still unknown, and possible side reactions have not yet been considered. In Aquincola tertiaricarbonis L108, Methylibium petroleiphilum PM1, and Methylibium sp. strain R8, we have now detected volatile hydrocarbons as by-products of the degradation of the tert-alkyl ether metabolites tert-butyl and tert-amyl alcohol (TBA and TAA, respectively). The alkene isobutene was formed only during TBA catabolism, while the beta and gamma isomers of isoamylene were produced only during TAA conversion. Both tert-alkyl alcohol degradation and alkene production were strictly oxygen dependent. However, the relative contribution of the dehydration reaction to total alcohol conversion increased with decreasing oxygen concentrations. In resting-cell experiments where the headspace oxygen content was adjusted to less than 2%, more than 50% of the TAA was converted to isoamylene. Isobutene formation from TBA was about 20-fold lower, reaching up to 4% alcohol turnover at low oxygen concentrations. It is likely that the putative tert-alkyl alcohol monooxygenase MdpJ, belonging to the Rieske nonheme mononuclear iron enzymes and found in all three strains tested, or an associated enzymatic step catalyzed the unusual elimination reaction. This was also supported by the detection of mdpJK genes in MTBE-degrading and isobutene-emitting enrichment cultures obtained from two treatment ponds operating at Leuna, Germany. The possible use of alkene formation as an easy-to-measure indicator of aerobic fuel oxygenate biodegradation in contaminated aquifers is discussed.
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Linking low-level stable isotope fractionation to expression of the cytochrome P450 monooxygenase-encoding ethB gene for elucidation of methyl tert-butyl ether biodegradation in aerated treatment pond systems. Appl Environ Microbiol 2010; 77:1086-96. [PMID: 21148686 DOI: 10.1128/aem.01698-10] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Multidimensional compound-specific stable isotope analysis (CSIA) was applied in combination with RNA-based molecular tools to characterize methyl tertiary (tert-) butyl ether (MTBE) degradation mechanisms occurring in biofilms in an aerated treatment pond used for remediation of MTBE-contaminated groundwater. The main pathway for MTBE oxidation was elucidated by linking the low-level stable isotope fractionation (mean carbon isotopic enrichment factor [ε(C)] of -0.37‰ ± 0.05‰ and no significant hydrogen isotopic enrichment factor [ε(H)]) observed in microcosm experiments to expression of the ethB gene encoding a cytochrome P450 monooxygenase able to catalyze the oxidation of MTBE in biofilm samples both from the microcosms and directly from the ponds. 16S rRNA-specific primers revealed the presence of a sequence 100% identical to that of Methylibium petroleiphilum PM1, a well-characterized MTBE degrader. However, neither expression of the mdpA genes encoding the alkane hydroxylase-like enzyme responsible for MTBE oxidation in this strain nor the related MTBE isotope fractionation pattern produced by PM1 could be detected, suggesting that this enzyme was not active in this system. Additionally, observed low inverse fractionation of carbon (ε(C) of +0.11‰ ± 0.03‰) and low fractionation of hydrogen (ε(H) of -5‰ ± 1‰) in laboratory experiments simulating MTBE stripping from an open surface water body suggest that the application of CSIA in field investigations to detect biodegradation may lead to false-negative results when volatilization effects coincide with the activity of low-fractionating enzymes. As shown in this study, complementary examination of expression of specific catabolic genes can be used as additional direct evidence for microbial degradation activity and may overcome this problem.
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Elsner M. Stable isotope fractionation to investigate natural transformation mechanisms of organic contaminants: principles, prospects and limitations. ACTA ACUST UNITED AC 2010; 12:2005-31. [PMID: 21038038 DOI: 10.1039/c0em00277a] [Citation(s) in RCA: 238] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Gas chromatography-isotope ratio mass spectrometry (GC-IRMS) has made it possible to analyze natural stable isotope ratios (e.g., (13)C/(12)C, (15)N/(14)N, (2)H/(1)H) of individual organic contaminants in environmental samples. They may be used as fingerprints to infer contamination sources, and may demonstrate, and even quantify, the occurrence of natural contaminant transformation by the enrichment of heavy isotopes that arises from degradation-induced isotope fractionation. This review highlights an additional powerful feature of stable isotope fractionation: the study of environmental transformation mechanisms. Isotope effects reflect the energy difference of isotopologues (i.e., molecules carrying a light versus a heavy isotope in a particular molecular position) when moving from reactant to transition state. Measuring isotope fractionation, therefore, essentially allows a glimpse at transition states! It is shown how such position-specific isotope effects are "diluted out" in the compound average measured by GC-IRMS, and how a careful evaluation in mechanistic scenarios and by dual isotope plots can recover the underlying mechanistic information. The mathematical framework for multistep isotope fractionation in environmental transformations is reviewed. Case studies demonstrate how isotope fractionation changes in the presence of mass transfer, enzymatic commitment to catalysis, multiple chemical reaction steps or limited bioavailability, and how this gives information about the individual process steps. Finally, it is discussed how isotope ratios of individual products evolve in sequential or parallel transformations, and what mechanistic insight they contain. A concluding session gives an outlook on current developments, future research directions and the potential for bridging the gap between laboratory and real world systems.
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Affiliation(s)
- Martin Elsner
- Institute of Groundwater Ecology, Helmholtz Zentrum München - German Research Center for Environmental Health, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany.
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Martínez-Lavanchy PM, Müller C, Nijenhuis I, Kappelmeyer U, Buffing M, McPherson K, Heipieper HJ. High stability and fast recovery of expression of the TOL plasmid-carried toluene catabolism genes of Pseudomonas putida mt-2 under conditions of oxygen limitation and oscillation. Appl Environ Microbiol 2010; 76:6715-23. [PMID: 20709833 PMCID: PMC2953008 DOI: 10.1128/aem.01039-10] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2010] [Accepted: 08/08/2010] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas putida mt-2 harbors the TOL plasmid (pWWO), which contains the genes encoding the enzymes necessary to degrade toluene aerobically. The xyl genes are clustered in the upper operon and encode the enzymes of the upper pathway that degrade toluene to benzoate, while the genes encoding the enzymes of the lower pathway (meta-cleavage pathway) that are necessary for the conversion of benzoate to tricarboxylic acid cycle intermediates, are encoded in a separate operon. In this study, the effects of oxygen availability and oscillation on the expression of catabolic genes for enzymes involved in toluene degradation were studied by using P. putida mt-2 as model bacterium. Quantitative reverse transcription-PCR was used to detect and quantify the expression of the catabolic genes xylM (a key gene of the upper pathway) and xylE (a key gene of the lower pathway) in cultures of P. putida mt-2 that were grown with toluene as a carbon source. Toluene degradation was shown to have a direct dependency on oxygen concentration, where gene expression of xylM and xylE decreased due to oxygen depletion during degradation. Under oscillating oxygen concentrations, P. putida mt-2 induced or downregulated xylM and xylE genes according to the O₂ availability in the media. During anoxic periods, P. putida mt-2 decreased the expression of xylM and xylE genes, while the expression of both xylM and xylE genes was immediately increased after oxygen became available again in the medium. These results suggest that oxygen is not only necessary as a cosubstrate for enzyme activity during the degradation of toluene but also that oxygen modulates the expression of the catabolic genes encoded by the TOL plasmid.
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Affiliation(s)
- Paula M. Martínez-Lavanchy
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany, Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany
| | - Christina Müller
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany, Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany
| | - Ivonne Nijenhuis
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany, Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany
| | - Uwe Kappelmeyer
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany, Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany
| | - Marieke Buffing
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany, Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany
| | - Kyle McPherson
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany, Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany
| | - Hermann J. Heipieper
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany, Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany
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Assessment of MTBE biodegradation pathways by two-dimensional isotope analysis in mixed bacterial consortia under different redox conditions. Appl Microbiol Biotechnol 2010; 88:309-17. [DOI: 10.1007/s00253-010-2730-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 06/02/2010] [Accepted: 06/12/2010] [Indexed: 11/27/2022]
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