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Lin Q, Yang Y, Zhang S, Sun F, Shen C, Su X. Enhanced biodegradation of polychlorinated biphenyls by co-cultivation of resuscitated strains with unique advantages. ENVIRONMENTAL RESEARCH 2024; 261:119699. [PMID: 39074776 DOI: 10.1016/j.envres.2024.119699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 07/14/2024] [Accepted: 07/26/2024] [Indexed: 07/31/2024]
Abstract
The investigation into viable but non-culturable (VBNC) bacteria through the implementation of resuscitation promoting factors (Rpfs) has broadened the potential sources for isolating strains capable of degrading polychlorinated biphenyls (PCBs). Nonetheless, there has been limited research on the efficacy of resuscitated strains and the potential improvement of their performance through co-cultivation. In this work, the PCB degradation potential of resuscitated strains, specifically Pseudomonas sp. HR1 and Achromobacter sp. HR2, as well as their co-cultures, was investigated. Of particular importance was the comparative analysis between the optimal co-culture and individual strains regarding their ability to degrade PCB homologs and mineralize intermediate metabolites. The results suggested that the resuscitated strains HR1 and HR2 demonstrated robust growth and effective degradation of Aroclor 1242. The co-culture CO13, with an optimal HR1 to HR2 ratio of 1:3, exhibited a remarkable improvement in PCB degradation and intermediate metabolite mineralization compared to individual strains. Analysis of functional genes and degradation metabolites revealed that both the individual strains and co-culture CO13 degraded PCBs via the HOPDA-benzoate pathway, then mineralized through protocatechuate meta- and ortho-cleavage pathways, as well as the catechol ortho-cleavage pathway. This study represents the first documentation of the improved PCB degradation through the co-cultivation of resuscitated strains, which highlights the great promise of these resuscitated strains and their co-cultures as effective bio-inoculants for enhanced bioremediation.
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Affiliation(s)
- Qihua Lin
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
| | - Yingying Yang
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
| | - Shusheng Zhang
- The Management Center of Wuyanling National Natural Reserve in Zhejiang, Wenzhou, 325500, China
| | - Faqian Sun
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China
| | - Chaofeng Shen
- Department of Environmental Engineering, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Xiaomei Su
- College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, 321004, China.
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Tao J, Wu W, Lin D, Yang K. Role of biochar pyrolysis temperature on intracellular and extracellular biodegradation of biochar-adsorbed organic compounds. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 346:123583. [PMID: 38365081 DOI: 10.1016/j.envpol.2024.123583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 02/09/2024] [Accepted: 02/14/2024] [Indexed: 02/18/2024]
Abstract
Immobilizing organic pollutants by adsorption of biochar in farmland soil is a cost-effective remediation method for contaminated soil. As the adsorption capacity of biochar is limited, biodegradation of biochar-adsorbed organic pollutants was a potential way to regenerate biochars and maintain the adsorption performance of biochars to lower the cost. It could be affected by the biochar pyrolysis temperature, but was not evaluated yet. In this study, biodegradation of adsorbed phenanthrene on a series of biochars with pyrolysis temperatures from 150 to 700 °C by Sphingobium yanoikuyae B1 was investigated using batch experiments of biodegradation kinetics at 30 °C, to explore the role of biochar pyrolysis temperature on biodegradation of biochar-adsorbed organic compounds. It was observed that 37.5-47.9% of adsorbed phenanthrene on moderate temperature-pyrolyzed biochars produced at 400 and 500 °C were biodegraded, less than that on high temperature-pyrolyzed biochars produced at ≥600 °C (48.8-60.8%) and low temperature-pyrolyzed biochars produced at ≤300 °C (63.4-92.5%). Phenanthrene adsorbed largely on the low temperature-pyrolyzed biochars by partition mechanism and thus is easily desorbed to water for a dominated intracellular biodegradation. On the high temperature-pyrolyzed biochars, phenanthrene is adsorbed largely by pore-filling mechanism and thus less desorbed to water for intracellular biodegradation. However, high temperature-pyrolyzed biochars can promote microbes to produce siderophore, H2O2 and thus release extracellular •OH for a dominated degradation of adsorbed phenanthrene by Fenton-like reaction. With the increase of biochar pyrolysis temperature, desorption and consequently the intracellular biodegradation of adsorbed phenanthrene on biochars decreased, while the secretion of siderophore and H2O2 by microbes on biochars increased to produce more extracellular •OH for degradation by Fenton-like reaction. The results could provide deep insights into the role of biochar pyrolysis temperature on biodegradation of biochar-adsorbed organic compounds, and optimize the selection of biochar with higher adsorption performance and easier regeneration for soil remediation.
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Affiliation(s)
- Jiaqi Tao
- Department of Environmental Science, Zhejiang University, Hangzhou, 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, 310058, China; Key Laboratory of Environmental Pollution and Ecological Health of Ministry of Education, Hangzhou, 310058, China
| | - Wenhao Wu
- Department of Environmental Science, Zhejiang University, Hangzhou, 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, 310058, China; Key Laboratory of Environmental Pollution and Ecological Health of Ministry of Education, Hangzhou, 310058, China.
| | - Daohui Lin
- Department of Environmental Science, Zhejiang University, Hangzhou, 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, 310058, China; Key Laboratory of Environmental Pollution and Ecological Health of Ministry of Education, Hangzhou, 310058, China
| | - Kun Yang
- Department of Environmental Science, Zhejiang University, Hangzhou, 310058, China; Zhejiang University-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou, 311200, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, 310058, China; Key Laboratory of Environmental Pollution and Ecological Health of Ministry of Education, Hangzhou, 310058, China
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Davenport R, Curtis‐Jackson P, Dalkmann P, Davies J, Fenner K, Hand L, McDonough K, Ott A, Ortega‐Calvo JJ, Parsons JR, Schäffer A, Sweetlove C, Trapp S, Wang N, Redman A. Scientific concepts and methods for moving persistence assessments into the 21st century. INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT 2022; 18:1454-1487. [PMID: 34989108 PMCID: PMC9790601 DOI: 10.1002/ieam.4575] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 09/29/2021] [Accepted: 12/06/2021] [Indexed: 05/19/2023]
Abstract
The evaluation of a chemical substance's persistence is key to understanding its environmental fate, exposure concentration, and, ultimately, environmental risk. Traditional biodegradation test methods were developed many years ago for soluble, nonvolatile, single-constituent test substances, which do not represent the wide range of manufactured chemical substances. In addition, the Organisation for Economic Co-operation and Development (OECD) screening and simulation test methods do not fully reflect the environmental conditions into which substances are released and, therefore, estimates of chemical degradation half-lives can be very uncertain and may misrepresent real environmental processes. In this paper, we address the challenges and limitations facing current test methods and the scientific advances that are helping to both understand and provide solutions to them. Some of these advancements include the following: (1) robust methods that provide a deeper understanding of microbial composition, diversity, and abundance to ensure consistency and/or interpret variability between tests; (2) benchmarking tools and reference substances that aid in persistence evaluations through comparison against substances with well-quantified degradation profiles; (3) analytical methods that allow quantification for parent and metabolites at environmentally relevant concentrations, and inform on test substance bioavailability, biochemical pathways, rates of primary versus overall degradation, and rates of metabolite formation and decay; (4) modeling tools that predict the likelihood of microbial biotransformation, as well as biochemical pathways; and (5) modeling approaches that allow for derivation of more generally applicable biotransformation rate constants, by accounting for physical and/or chemical processes and test system design when evaluating test data. We also identify that, while such advancements could improve the certainty and accuracy of persistence assessments, the mechanisms and processes by which they are translated into regulatory practice and development of new OECD test guidelines need improving and accelerating. Where uncertainty remains, holistic weight of evidence approaches may be required to accurately assess the persistence of chemicals. Integr Environ Assess Manag 2022;18:1454-1487. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
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Affiliation(s)
| | | | - Philipp Dalkmann
- Bayer AG, Crop Science Division, Environmental SafetyMonheimGermany
| | | | - Kathrin Fenner
- Eawag, Swiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
- Department of ChemistryUniversity of ZürichZürichSwitzerland
| | - Laurence Hand
- Syngenta, Product Safety, Jealott's Hill International Research CentreBracknellUK
| | | | - Amelie Ott
- School of EngineeringNewcastle UniversityNewcastle upon TyneUK
- European Centre for Ecotoxicology and Toxicology of Chemicals (ECETOC)BrusselsBelgium
| | - Jose Julio Ortega‐Calvo
- Instituto de Recursos Naturales y Agrobiología de SevillaConsejo Superior de Investigaciones CientíficasSevillaSpain
| | - John R. Parsons
- Institute for Biodiversity and Ecosystem DynamicsUniversity of AmsterdamAmsterdamThe Netherlands
| | - Andreas Schäffer
- RWTH Aachen University, Institute for Environmental ResearchAachenGermany
| | - Cyril Sweetlove
- L'Oréal Research & InnovationEnvironmental Research DepartmentAulnay‐sous‐BoisFrance
| | - Stefan Trapp
- Department of Environmental EngineeringTechnical University of DenmarkBygningstorvetLyngbyDenmark
| | - Neil Wang
- Total Marketing & ServicesParis la DéfenseFrance
| | - Aaron Redman
- ExxonMobil Petroleum and ChemicalMachelenBelgium
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4
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Tao J, Wu W, Lin D, Yang K. Microbial degradation of nondesorbable organic compounds on biochars by extracellular reactive oxygen species. JOURNAL OF HAZARDOUS MATERIALS 2022; 439:129625. [PMID: 35905607 DOI: 10.1016/j.jhazmat.2022.129625] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 07/12/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
Knowledge of microbial degradation of biochar-adsorbed organic pollutants is essential for recovering adsorption performance of biochars and reducing secondary pollution in soil remediation. In previous study, desorption of organic compounds from biochars was perceived as a prerequisite for the microbial degradation. However, microbial degradation of the nondesorbable organic compounds on biochars has not been studied. Therefore, degradation of nondesorbable naphthalene (NAPH), phenanthrene (PHEN) and pyrene (PYR) on a wood chip-derived biochar (WBC700) by Sphingobium yanoikuyae B1 was investigated. Significant microbial degradations of nondesorbable organic compounds were observed and followed the order of NAPH < PHEN < PYR. It was newly observed in this study that the microbial degradation of nondesorbable organic compounds on WBC700 was mainly attributed to the •OH in extracellular fluid of Sphingobium yanoikuyae B1. The extracellular •OH was produced through a Fenton-like reaction involved siderophore, H2O2 and iron ions, which could be significantly enhanced by WBC700. Microbial degradation was higher for larger organic compound (e.g., PYR), because larger molecules were adsorbed in relatively larger micropores of WBC700 and thus could be accessible to more extracellular •OH for degradation. The obtained results could provide a new insight into the microbial degradation of biochar-adsorbed organic pollutants in soil remediation.
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Affiliation(s)
- Jiaqi Tao
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China; Key Laboratory of Environmental Pollution and Ecological Health of Ministry of Education, Hangzhou 310058, China
| | - Wenhao Wu
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China; Key Laboratory of Environmental Pollution and Ecological Health of Ministry of Education, Hangzhou 310058, China.
| | - Daohui Lin
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China; Key Laboratory of Environmental Pollution and Ecological Health of Ministry of Education, Hangzhou 310058, China
| | - Kun Yang
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang University-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou 311200, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China; Key Laboratory of Environmental Pollution and Ecological Health of Ministry of Education, Hangzhou 310058, China
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5
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Cao S, Wang S, Zhao Y, Wang L, Ma Y, Schäffer A, Ji R. Fate of bisphenol S (BPS) and characterization of non-extractable residues in soil: Insights into persistence of BPS. ENVIRONMENT INTERNATIONAL 2020; 143:105908. [PMID: 32615349 DOI: 10.1016/j.envint.2020.105908] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 06/17/2020] [Accepted: 06/17/2020] [Indexed: 06/11/2023]
Abstract
The environmental fate and persistence of bisphenol S (BPS), a substitute for bisphenol A (BPA), are unclear. This study used 14C-labeled BPS to examine the fate, biodegradation, and residue properties of BPS incubated in an oxic soil for 28 days. BPS dissipated quickly, with a half-life of 2.8 days. Most of the BPS was mineralized (53.6 ± 0.2% of initial amount by day 28) or transformed into non-extractable residues (NERs) (45.1 ± 0.3%), with generation of minor extractable residues (3.7 ± 0.2%) containing two metabolites. NERs were formed mainly via physico-chemical entrapment (51.1 ± 2.4% of the total NERs, consisting almost exclusively of BPS) and ester-linkages (31.5 ± 3.0% of the total NERs, consisting of both BPS and polar metabolites). When mixed with fresh soil, BPS-derived NERs became unstable and bioavailable. Subsequent mineralization was determined for 19.5 ± 1.1% of the total NERs and 35.5 ± 2.6% of the physico-chemically entrapped BPS. A fate model was used to describe the kinetics of NER formation, which indicated that microbial activity in soil could have strongly reduced the kinetic rate of the release of physico-chemically entrapped NERs into free form and therefore increased the stability of this type of NERs in soil. Our results provide unique insights into the fate of BPS in soil and suggest that while BPS is biodegradable, it includes the formation of large amounts of reversibly physico-chemically entrapped and covalently bound ester-linked NERs. The instability of these NERs should be considered in assessments on environmental persistence and risks of BPS. Our study also points out the environmental importance of NERs of agrochemicals.
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Affiliation(s)
- Siqi Cao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, 210023 Nanjing, China
| | - Songfeng Wang
- Institue of Botany, Jiangsu Province and Chinese Academy of Sciences, Zhongshanmenwai Qianhuhoucun 1, 210014 Nanjing, China
| | - Yingying Zhao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, 210023 Nanjing, China
| | - Lianhong Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, 210023 Nanjing, China
| | - Yini Ma
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, 210023 Nanjing, China
| | - Andreas Schäffer
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, 210023 Nanjing, China; Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Rong Ji
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, 210023 Nanjing, China.
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Liu L, Bilal M, Duan X, Iqbal HMN. Mitigation of environmental pollution by genetically engineered bacteria - Current challenges and future perspectives. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 667:444-454. [PMID: 30833243 DOI: 10.1016/j.scitotenv.2019.02.390] [Citation(s) in RCA: 122] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/15/2019] [Accepted: 02/15/2019] [Indexed: 02/08/2023]
Abstract
Industries are the paramount driving force for the economic and technological development of society. However, the flourishing industrialization and unimpeded growth of current production unit's result in widespread environmental pollution due to increased discharge of wastes loaded with baleful, hazardous, and carcinogenic contaminants. Physicochemical-based remediation means are costly, create a secondary disposal problem and remain inadequate for pollution mitigating because of the continuous emergence of new recalcitrant pollutants. Due to eco-friendly, social acceptance, and lesser health hazards, microbial bioremediation has received considerable global attention for pollution abatement. Moreover, with the recent advancement in biotechnology and microbiology, genetically engineered bacteria with high ability to remove environmental pollutants are widely used in the fields of environmental restoration, resulting in the bioremediation in a more viable and eco-friendly way. This review summarized the advantages of genetically engineered bacteria and their application in the treatment of a wide variety of environmental contaminants such as synthetic dyestuff, heavy metal, petroleum hydrocarbons, polychlorinated biphenyls, phenazines and agricultural chemicals which will include herbicides, pesticides, and fertilizers. Considering the risk of genetic material exchange by using genetically engineered bacteria, the challenges and limitations associated with the application of recombinant bacteria on contaminated sites are also discussed. An integrated microbiological, biological and ecological acquaintance accompanied by field engineering designs are the desired features for effective in situ bioremediation of hazardous waste polluted sites by recombinant bacteria.
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Affiliation(s)
- Lina Liu
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huaian 223003, China
| | - Muhammad Bilal
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huaian 223003, China.
| | - Xuguo Duan
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Hafiz M N Iqbal
- Tecnologico de Monterrey, School of Engineering and Sciences, Campus Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, N.L. CP 64849, Mexico.
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Brock AL, Rein A, Polesel F, Nowak KM, Kästner M, Trapp S. Microbial Turnover of Glyphosate to Biomass: Utilization as Nutrient Source and Formation of AMPA and Biogenic NER in an OECD 308 Test. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:5838-5847. [PMID: 30994338 DOI: 10.1021/acs.est.9b01259] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Environmental fate assessment of chemicals involves standardized simulation tests with isotope-labeled molecules to balance transformation, mineralization, and formation of nonextractable residues (NER). Methods to predict microbial turnover and biogenic NER have been developed, having limited use when metabolites accumulate, the chemicals are not the only C source, or provide for other macroelements. To improve predictive capability, we extended a recently developed method for microbial growth yield estimation to account for incomplete degradation and multiple-element assimilation and combined it with a dynamic model for fate description in soils and sediments. We evaluated the results against the unique experimental data of 13C3-15N co-labeled glyphosate turnover with AMPA formation in water-sediment systems (OECD 308). Balancing 13C- and 15N- fluxes to biomass showed a pronounced shift of glyphosate transformation from full mineralization to AMPA formation. This may be explained by various hypotheses, for example, the limited substrate turnover inherent to the batch conditions of the test system causing microbial starvation or inhibition by P release. Modeling results indicate initial N overload due to the lower C/N ratio in glyphosate compared to average cell composition leading to subsequent C demand and accumulation of AMPA.
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Affiliation(s)
- Andreas Libonati Brock
- Department of Environmental Engineering , Technical University of Denmark , Bygningstorvet 115 , 2800 Kgs . Lyngby , Denmark
| | - Arno Rein
- Chair of Hydrogeology , Technical University of Munich , Arcisstrasse 21 , Munich 80333 , Germany
| | - Fabio Polesel
- Department of Environmental Engineering , Technical University of Denmark , Bygningstorvet 115 , 2800 Kgs . Lyngby , Denmark
| | - Karolina M Nowak
- Department of Environmental Biotechnology , Helmholtz-Centre for Environmental Research-UFZ , Permoserstrasse 15 , 04318 Leipzig , Germany
| | - Matthias Kästner
- Department of Environmental Biotechnology , Helmholtz-Centre for Environmental Research-UFZ , Permoserstrasse 15 , 04318 Leipzig , Germany
| | - Stefan Trapp
- Department of Environmental Engineering , Technical University of Denmark , Bygningstorvet 115 , 2800 Kgs . Lyngby , Denmark
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Brimo K, Garnier P, Lafolie F, Séré G, Ouvrard S. In situ long-term modeling of phenanthrene dynamics in an aged contaminated soil using the VSOIL platform. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 619-620:239-248. [PMID: 29149748 DOI: 10.1016/j.scitotenv.2017.11.089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 10/13/2017] [Accepted: 11/08/2017] [Indexed: 06/07/2023]
Abstract
Management and remediation actions of polycyclic aromatic hydrocarbons (PAH) contaminated sites require an accurate knowledge of the dynamics of these chemicals in situ under real conditions. Here we developed, under the Virtual Soil Platform, a global model for PAH that describes the principal physical and biological processes controlling the dynamics of PAH in soil under real climatic conditions. The model was applied first to simulate the observed dynamics of phenanthrene in situ field experimental plots of industrial contaminated soil. In a second step, different long-term scenarios of climate change or bioavailability increase were applied. Our results show that the model can adequately predict the fate of phenanthrene and can contribute to clarify some of unexplored aspects regarding the behavior of phenanthrene in soil like its degradation mechanism and stabilization. Tested prospective scenarios showed that bioavailability increase (through the addition of solvent or surfactants) resulted in significant increase in substrate transfer rate, hence reducing remediation time. Regarding climate change effect, the model indicated that phenanthrene concentration decreased by 54% during 40years with a natural attenuation and both scenarios chosen for climatic boundaries provided very similar results.
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Affiliation(s)
- Khaled Brimo
- INRA, EcoSys, UMR1405, Université Paris-Saclay, 78850 Thiverval-Grignon, France; INRA, Laboratoire Sols et Environnement, UMR 1120, F-54518 Vandoeuvre-lès-Nancy, France; Université de Lorraine, Laboratoire Sols et Environnement, UMR 1120, F-54518 Vandoeuvre-lès-Nancy, France; Agence de l'Environnement et de la Maîtrise de l'Energie, 20 avenue du Grésillé, BP 90406, F-49004 Angers Cedex 01, France
| | - Patricia Garnier
- INRA, EcoSys, UMR1405, Université Paris-Saclay, 78850 Thiverval-Grignon, France
| | - François Lafolie
- EMMAH, Université d'Avignon et des Pays de Vaucluse, INRA, 84914 Avignon, France
| | - Geoffroy Séré
- INRA, Laboratoire Sols et Environnement, UMR 1120, F-54518 Vandoeuvre-lès-Nancy, France; Université de Lorraine, Laboratoire Sols et Environnement, UMR 1120, F-54518 Vandoeuvre-lès-Nancy, France
| | - Stéphanie Ouvrard
- INRA, Laboratoire Sols et Environnement, UMR 1120, F-54518 Vandoeuvre-lès-Nancy, France; Université de Lorraine, Laboratoire Sols et Environnement, UMR 1120, F-54518 Vandoeuvre-lès-Nancy, France.
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9
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Trapp S, Brock AL, Nowak K, Kästner M. Prediction of the Formation of Biogenic Nonextractable Residues during Degradation of Environmental Chemicals from Biomass Yields. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:663-672. [PMID: 29214805 DOI: 10.1021/acs.est.7b04275] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Degradation tests with radio or stable isotope labeled compounds enable the detection of the formation of nonextractable residues (NER). In PBT and vPvB assessment, remobilisable NER are considered as a potential risk while biogenic NER from incorporation of labeled carbon into microbial biomass are treated as degradation products. Relationships between yield, released CO2 (as indicator of microbial activity and mineralization) and microbial growth can be used to estimate the formation of biogenic NER. We provide a new approach for calculation of potential substrate transformation to microbial biomass (theoretical yield) based on Gibbs free energy and microbially available electrons. We compare estimated theoretical yields of biotechnological substrates and of chemicals of environmental concern with experimentally determined yields for validation of the presented approach. A five-compartment dynamic model is applied to simulate experiments of 13C-labeled 2,4-D and ibuprofen turnover. The results show that bioNER increases with time, and that most bioNER originates from microbial proteins. Simulations with precalculated input data demonstrate that precalculation of yields reduces the number of fit parameters considerably, increases confidence in fitted kinetic data, and reduces the uncertainty of the simulation results.
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Affiliation(s)
- Stefan Trapp
- Department of Environmental Engineering, Technical University of Denmark , Bygningstorvet bd. 115, DK-2800 Kgs. Lyngby, Denmark
| | - Andreas Libonati Brock
- Department of Environmental Engineering, Technical University of Denmark , Bygningstorvet bd. 115, DK-2800 Kgs. Lyngby, Denmark
| | - Karolina Nowak
- Helmholtz-Centre for Environmental Research - UFZ , Department of Environmental Biotechnology, Permoserstrasse 15, 04318 Leipzig, Germany
| | - Matthias Kästner
- Helmholtz-Centre for Environmental Research - UFZ , Department of Environmental Biotechnology, Permoserstrasse 15, 04318 Leipzig, Germany
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Zhao Q, Bilal M, Yue S, Hu H, Wang W, Zhang X. Identification of biphenyl 2, 3-dioxygenase and its catabolic role for phenazine degradation in Sphingobium yanoikuyae B1. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2017; 204:494-501. [PMID: 28930694 DOI: 10.1016/j.jenvman.2017.09.027] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 09/06/2017] [Accepted: 09/08/2017] [Indexed: 06/07/2023]
Abstract
Phenazines are important nitrogen-containing secondary metabolites that display a range of biological functionalities. However, these compounds have shown lethal effects on humans and, the fate of phenazine in the ecosystem remains uncertain. In this study, we investigated that Sphingobium yanoikuyae B1 could utilize phenazine as a sole carbon source for growth. Intermediate produced during phenazine degradation was purified and identified as 1, 2-dihydrogen 1, 2-dihydroxy phenazine. Biphenyl 2, 3-dioxygenase was determined to be the initial dioxygenase for phenazine degradation through gene cloning and whole cell transformation techniques. Phenazine was converted to 1, 2-dihydrogen 1, 2-dihydroxy phenazine through hydrogenation and hydroxylation, which then transformed to 2-hydroxy phenazine through spontaneous dehydration. ThebphA1fA2f, were evidenced to be the only genes encoding the initial dioxygenase for phenazine degradation. BphB (dihydrodiol dehydrogenase) and BphC (2,3-dihydroxybiphenyl 1,2-dioxygenase) did not exhibit any 1, 2-dihydrogen 1, 2-dihydroxy phenazine and 1, 2-dihydroxy phenazine degradation capability, suggesting no contribution in phenazine degradation. Phylogenetic analysis of the dioxygenases demonstrated enormous biodegradation potential in strain B1. In conclusion, this study opens up new possibilities in better understanding the phenazine degradation in the environment.
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Affiliation(s)
- Qiang Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Muhammad Bilal
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Shengjie Yue
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Hongbo Hu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China; National Experimental Teaching Center for Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Wei Wang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xuehong Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
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11
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Birch H, Andersen HR, Comber M, Mayer P. Biodegradation testing of chemicals with high Henry's constants - Separating mass and effective concentration reveals higher rate constants. CHEMOSPHERE 2017; 174:716-721. [PMID: 28208083 DOI: 10.1016/j.chemosphere.2017.02.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 01/31/2017] [Accepted: 02/01/2017] [Indexed: 06/06/2023]
Abstract
During simulation-type biodegradation tests, volatile chemicals will continuously partition between water phase and headspace. This study addressed how (1) this partitioning affects test results and (2) can be accounted for by combining equilibrium partition and dynamic biodegradation models. An aqueous mixture of 9 (semi)volatile chemicals was first generated using passive dosing and then diluted with environmental surface water producing concentrations in the ng/L to μg/L range. After incubation for 2 h to 4 weeks, automated Headspace Solid Phase Microextraction (HS-SPME) was applied directly on the test systems to measure substrate depletion by biodegradation relatively to abiotic controls. HS-SPME was also applied to determine air to water partitioning ratios. Biodegradation rate constants relating to the chemical in the water phase, kwater, were generally a factor 1 to 11 times higher than biodegradation rate constants relating to the total mass of chemical in the test system, ksystem, with one exceptional factor of 72 times for a long chain alkane. True water phase degradation rate constants were found (i) more appropriate for risk assessment than test system rate constants, (ii) to facilitate extrapolation to other air-water systems and (iii) to be better defined input parameters for aquatic exposure and fate models.
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Affiliation(s)
- Heidi Birch
- Technical University of Denmark, Department of Environmental Engineering, Bygningstorvet, Building 115, 2800 Kgs. Lyngby, Denmark.
| | - Henrik R Andersen
- Technical University of Denmark, Department of Environmental Engineering, Bygningstorvet, Building 115, 2800 Kgs. Lyngby, Denmark.
| | - Mike Comber
- Mike Comber Consulting, Bridford, Exeter, UK.
| | - Philipp Mayer
- Technical University of Denmark, Department of Environmental Engineering, Bygningstorvet, Building 115, 2800 Kgs. Lyngby, Denmark.
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12
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Kästner M, Nowak KM, Miltner A, Schäffer A. (Multiple) Isotope probing approaches to trace the fate of environmental chemicals and the formation of non-extractable ‘bound’ residues. Curr Opin Biotechnol 2016; 41:73-82. [DOI: 10.1016/j.copbio.2016.05.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 05/12/2016] [Accepted: 05/16/2016] [Indexed: 10/21/2022]
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13
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Brimo K, Garnier P, Sun S, Bertrand-Krajewski JL, Cébron A, Ouvrard S. Using a Bayesian approach to improve and calibrate a dynamic model of polycyclic aromatic hydrocarbons degradation in an industrial contaminated soil. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 215:27-37. [PMID: 27176762 DOI: 10.1016/j.envpol.2016.04.094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 04/26/2016] [Accepted: 04/28/2016] [Indexed: 06/05/2023]
Abstract
A novel kinetics model that describes the dynamics of polycyclic aromatic hydrocarbons (PAHs) in contaminated soils is presented. The model includes two typical biodegradation pathways: the co-metabolic pathway using pseudo first order kinetics and the specific biodegradation pathway modeled using Monod kinetics. The sorption of PAHs to the solid soil occurs through bi-phasic fist order kinetics, and two types of non-extractible bounded residues are considered: the biogenic and the physically sequestrated into soil matrix. The PAH model was developed in Matlab, parameterized and tested successfully on batch experimental data using a Bayesian approach (DREAM). Preliminary results led to significant model simplifications. They also highlighted that the specific biodegradation pathway was the most efficient at explaining experimental data, as would be expected for an old industrial contaminated soil. Global analysis of sensitivity showed that the amount of PAHs ultimately degraded was mostly governed by physicochemical interactions rather than by biological activity.
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Affiliation(s)
- Khaled Brimo
- INRA, EcoSys, UMR1405, Université Paris-Saclay, 78850, Thiverval-Grignon, France; INRA, Laboratoire Sols et Environnement, UMR 1120, F-54518, Vandoeuvre-lès-Nancy, France; Université de Lorraine, Laboratoire Sols et Environnement, UMR 1120, F-54518, Vandoeuvre-lès-Nancy, France; Agence de l'Environnement et de la Maîtrise de l'Energie, 20 avenue du Grésillé, BP 90406, F-49004, Angers Cedex 01, France
| | - Patricia Garnier
- INRA, EcoSys, UMR1405, Université Paris-Saclay, 78850, Thiverval-Grignon, France
| | - Siao Sun
- Key Laboratory of Regional Sustainable Development Modeling, Institute of Geographical Sciences and Natural Resource Research, Chinese Academy of Sciences, 100101, Beijing, China
| | | | - Aurélie Cébron
- CNRS, LIEC, UMR 7360, Faculté des Sciences et Technologies, BP 70239, F-54506, Vandoeuvre-lès-Nancy Cedex, France; Université de Lorraine, LIEC, UMR 7360, Faculté des Sciences et Technologies, BP 70239, F-54506, Vandoeuvre-lès-Nancy Cedex, France
| | - Stéphanie Ouvrard
- INRA, Laboratoire Sols et Environnement, UMR 1120, F-54518, Vandoeuvre-lès-Nancy, France; Université de Lorraine, Laboratoire Sols et Environnement, UMR 1120, F-54518, Vandoeuvre-lès-Nancy, France.
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14
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Deary ME, Ekumankama CC, Cummings SP. Development of a novel kinetic model for the analysis of PAH biodegradation in the presence of lead and cadmium co-contaminants. JOURNAL OF HAZARDOUS MATERIALS 2016; 307:240-252. [PMID: 26785214 DOI: 10.1016/j.jhazmat.2015.12.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 11/16/2015] [Accepted: 12/09/2015] [Indexed: 06/05/2023]
Abstract
We report on the results of a 40 week study in which the biodegradation of 16 US EPA polycyclic aromatic hydrocarbons (PAHs) was followed in microcosms containing soil of high organic carbon content (11%) in the presence and absence of lead and cadmium co-contaminants. The total spiked PAH concentration was 2166mg/kg. Mercury amendment was also made to give an abiotic control. A novel kinetic model has been developed to explain the observed biphasic nature of PAH degradation. The model assumes that PAHs are distributed across soil phases of varying degrees of bioaccessibility. The results of the analysis suggest that overall percentage PAH loss is dependent on the respective rates at which the PAHs (a) are biodegraded by soil microorganisms in pore water and bioaccessible soil phases and (b) migrate from bioaccessible to non-bioaccessible soil phases. In addition, migration of PAHs to non-bioaccessible and non-Soxhlet-extractable soil phases associated with the humin pores gives rise to an apparent removal process. The presence of metal co-contaminants shows a concentration dependent inhibition of the biological degradation processes that results in a reduction in overall degradation. Lead appears to have a marginally greater inhibitory effect than cadmium.
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Affiliation(s)
- Michael E Deary
- Department of Geography,Faculty of Engineering and Environment, Northumbria University, Ellison Building, Newcastle upon Tyne NE1 8ST, United Kingdom.
| | - Chinedu C Ekumankama
- Department of Geography,Faculty of Engineering and Environment, Northumbria University, Ellison Building, Newcastle upon Tyne NE1 8ST, United Kingdom
| | - Stephen P Cummings
- Faculty of Health and Life Sciences, Northumbria University, Ellison Building, Newcastle upon Tyne NE1 8ST, United Kingdom
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15
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Rein A, Adam IKU, Miltner A, Brumme K, Kästner M, Trapp S. Impact of bacterial activity on turnover of insoluble hydrophobic substrates (phenanthrene and pyrene)-Model simulations for prediction of bioremediation success. JOURNAL OF HAZARDOUS MATERIALS 2016; 306:105-114. [PMID: 26705887 DOI: 10.1016/j.jhazmat.2015.12.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 11/17/2015] [Accepted: 12/03/2015] [Indexed: 06/05/2023]
Abstract
Many attempts for bioremediation of polycyclic aromatic hydrocarbon (PAH) contaminated sites failed in the past, but the reasons for this failure are not well understood. Here we apply and improve a model for integrated assessment of mass transfer, biodegradation and residual concentrations for predicting the success of remediation actions. First, we provide growth parameters for Mycobacterium rutilum and Mycobacterium pallens growing on phenanthrene (PHE) or pyrene (PYR) degraded the PAH completely at all investigated concentrations. Maximum metabolic rates vmax and growth rates μ were similar for the substrates PHE and PYR and for both strains. The investigated Mycobacterium species were not superior in PHE degradation to strains investigated earlier with this method. Real-world degradation scenario simulations including diffusive flux to the microbial cells indicate: that (i) bioaugmentation only has a small, short-lived effect; (ii) Increasing sorption shifts the remaining PAH to the adsorbed/sequestered PAH pool; (iii) mobilizing by solvents or surfactants resulted in a significant decrease of the sequestered PAH, and (iv) co-metabolization e.g. by compost addition can contribute significantly to the reduction of PAH, because active biomass is maintained at a high level by the compost. The model therefore is a valuable contribution to the assessment of potential remediation action at PAH-polluted sites.
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Affiliation(s)
- Arno Rein
- Department of Environmental Engineering, Technical University of Denmark, Miljøvej bd. 113, DK-2800 Kgs. Lyngby, Denmark
| | - Iris K U Adam
- UFZ-Helmholtz-Centre for Environmental Research, Department of Environmental Biotechnology, Permoserstr. 15, 04318 Leipzig, Germany
| | - Anja Miltner
- UFZ-Helmholtz-Centre for Environmental Research, Department of Environmental Biotechnology, Permoserstr. 15, 04318 Leipzig, Germany
| | - Katja Brumme
- UFZ-Helmholtz-Centre for Environmental Research, Department of Environmental Biotechnology, Permoserstr. 15, 04318 Leipzig, Germany
| | - Matthias Kästner
- UFZ-Helmholtz-Centre for Environmental Research, Department of Environmental Biotechnology, Permoserstr. 15, 04318 Leipzig, Germany.
| | - Stefan Trapp
- Department of Environmental Engineering, Technical University of Denmark, Miljøvej bd. 113, DK-2800 Kgs. Lyngby, Denmark
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16
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Kästner M, Miltner A. Application of compost for effective bioremediation of organic contaminants and pollutants in soil. Appl Microbiol Biotechnol 2016; 100:3433-49. [PMID: 26921182 DOI: 10.1007/s00253-016-7378-y] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 02/01/2016] [Accepted: 02/03/2016] [Indexed: 01/27/2023]
Abstract
Soils contaminated with hazardous chemicals worldwide are awaiting remediation activities; bioremediation is often considered as a cost-effective remediation approach. Potential bioapproaches are biostimulation, e.g. by addition of nutrients, fertiliser and organic substrates, and bioaugmentation by addition of compound-degrading microbes or of organic amendments containing active microorganisms, e.g. activated sludge or compost. In most contaminated soils, the abundance of the intrinsic metabolic potential is too low to be improved by biostimulation alone, since the physical and chemical conditions in these soils are not conducive to biodegradation. In the last few decades, compost or farmyard manure addition as well as composting with various organic supplements have been found to be very efficient for soil bioremediation. In the present minireview, we provide an overview of the composting and compost addition approaches as 'stimulants' of natural attenuation. Laboratory degradation experiments are often biased either by not considering the abiotic factors or by focusing solely on the elimination of the chemicals without taking the biotic factors and processes into account. Therefore, we first systemise the concepts of composting and compost addition, then summarise the relevant physical, chemical and biotic factors and mechanisms for improved contaminant degradation triggered by compost addition. These factors and mechanisms are of particular interest, since they are more relevant and easier to determine than the composition of the degrading community, which is also addressed in this review. Due to the mostly empirical knowledge and the nonstandardised biowaste or compost materials, the field use of these approaches is highly challenging, but also promising. Based on the huge metabolic diversity of microorganisms developing during the composting processes, a highly complex metabolic diversity is established as a 'metabolic memory' within developing and mature compost materials. Compost addition can thus be considered as a 'super-bioaugmentation' with a complex natural mixture of degrading microorganisms, combined with a 'biostimulation' by nutrient containing readily to hardly degradable organic substrates. It also improves the abiotic soil conditions, thus enhancing microbial activity in general. Finally, this minireview also aims at guiding potential users towards full exploitation of the potentials of this approach.
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Affiliation(s)
- Matthias Kästner
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research - UFZ, Permoserstraße 15, 04318, Leipzig, Germany.
| | - Anja Miltner
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research - UFZ, Permoserstraße 15, 04318, Leipzig, Germany
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17
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Liu L, Binning PJ, Smets BF. Evaluating alternate biokinetic models for trace pollutant cometabolism. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:2230-6. [PMID: 25546565 DOI: 10.1021/es5035393] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Mathematical models of cometabolic biodegradation kinetics can improve our understanding of the relevant microbial reactions and allow us to design in situ or in-reactor applications of cometabolic bioremediation. A variety of models are available, but their ability to describe experimental data has not been systematically evaluated for a variety of operational/experimental conditions. Here five different models were considered: first-order; Michaelis-Menten; reductant; competition; and combined models. The models were assessed on their ability to fit data from simulated batch experiments covering a realistic range of experimental conditions. The simulated observations were generated by using the most complex model structure and parameters based on the literature, with added experimental error. Three criteria were used to evaluate model fit: ability to fit the simulated experimental data, identifiability of parameters using a colinearity analysis, and suitability of the model size and complexity using the Bayesian and Akaike Information criteria. Results show that no single model fits data well for a range of experimental conditions. The reductant model achieved best results, but required very different parameter sets to simulate each experiment. Parameter nonuniqueness was likely to be due to the parameter correlation. These results suggest that the cometabolic models must be further developed if they are to reliably simulate experimental and operational data.
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Affiliation(s)
- Li Liu
- Department of Environmental Engineering, Technical, University of Denmark , Bygningstorvet 115, 2800 Kgs.Lyngby, Denmark
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18
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Liu L, Helbling DE, Kohler HPE, Smets BF. A model framework to describe growth-linked biodegradation of trace-level pollutants in the presence of coincidental carbon substrates and microbes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:13358-13366. [PMID: 25321868 DOI: 10.1021/es503491w] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Pollutants such as pesticides and their degradation products occur ubiquitously in natural aquatic environments at trace concentrations (μg L(-1) and lower). Microbial biodegradation processes have long been known to contribute to the attenuation of pesticides in contaminated environments. However, challenges remain in developing engineered remediation strategies for pesticide-contaminated environments because the fundamental processes that regulate growth-linked biodegradation of pesticides in natural environments remain poorly understood. In this research, we developed a model framework to describe growth-linked biodegradation of pesticides at trace concentrations. We used experimental data reported in the literature or novel simulations to explore three fundamental kinetic processes in isolation. We then combine these kinetic processes into a unified model framework. The three kinetic processes described were: the growth-linked biodegradation of micropollutant at environmentally relevant concentrations; the effect of coincidental assimilable organic carbon substrates; and the effect of coincidental microbes that compete for assimilable organic carbon substrates. We used Monod kinetic models to describe substrate utilization and microbial growth rates for specific pesticide and degrader pairs. We then extended the model to include terms for utilization of assimilable organic carbon substrates by the specific degrader and coincidental microbes, growth on assimilable organic carbon substrates by the specific degrader and coincidental microbes, and endogenous metabolism. The proposed model framework enables interpretation and description of a range of experimental observations on micropollutant biodegradation. The model provides a useful tool to identify environmental conditions with respect to the occurrence of assimilable organic carbon and coincidental microbes that may result in enhanced or reduced micropollutant biodegradation.
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Affiliation(s)
- Li Liu
- Department of Environmental Engineering, Technical, University of Denmark , Bygningstorvet 115, 2800 Kgs. Lyngby, Denmark
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