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Al-Isawi RHK, Scholz M, Al-Faraj FAM. Assessment of diesel-contaminated domestic wastewater treated by constructed wetlands for irrigation of chillies grown in a greenhouse. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:25003-25023. [PMID: 27677991 PMCID: PMC5124056 DOI: 10.1007/s11356-016-7706-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Accepted: 09/13/2016] [Indexed: 06/06/2023]
Abstract
In order to avoid environmental pollution and eliminate the need for using fertiliser, this study assessed for the first time the optimum performance of mature (in operation since 2011) vertical flow constructed wetlands in treating domestic wastewater (with and without hydrocarbon) and the subsequent recycling of the outflow to irrigate chillies (De Cayenne; Capsicum annuum (Linnaeus) Longum Group 'De Cayenne') grown in a greenhouse. Various variables were investigated to assess the treatment performance. Concerning chilli fruit numbers, findings showed that the highest fruit yields for all wetland filters were associated with those that received inflow wastewater with a high loading rate, reflecting the high nutrient availability in treated wastewater, which is of obvious importance for yield production. Findings also indicated that wetlands without hydrocarbon, small aggregate size, low contact time and low inflow loading rate provided high marketable yields (expressed in economic return). In comparison, chillies irrigated by filters with hydrocarbon contamination, small aggregate size, high contact time and high loading rate also resulted in high marketable yields of chillies, which pointed out the role of high contact time and high inflow load for better diesel degradation rates.
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Affiliation(s)
- Rawaa H K Al-Isawi
- Civil Engineering Research Group, School of Computing, Science and Engineering, The University of Salford, Newton Building, Salford, England, M5 4WT, UK
| | - Miklas Scholz
- Civil Engineering Research Group, School of Computing, Science and Engineering, The University of Salford, Newton Building, Salford, England, M5 4WT, UK.
- Division of Water Resources Engineering, Faculty of Engineering, Lund University, P.O. Box 118, 221 00, Lund, Sweden.
| | - Furat A M Al-Faraj
- Civil Engineering Research Group, School of Computing, Science and Engineering, The University of Salford, Newton Building, Salford, England, M5 4WT, UK
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52
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Rajtor M, Piotrowska-Seget Z. Prospects for arbuscular mycorrhizal fungi (AMF) to assist in phytoremediation of soil hydrocarbon contaminants. CHEMOSPHERE 2016; 162:105-116. [PMID: 27487095 DOI: 10.1016/j.chemosphere.2016.07.071] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 07/22/2016] [Accepted: 07/23/2016] [Indexed: 06/06/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) form mutualistic associations with the roots of 80-90% of vascular plant species and may constitute up to 50% of the total soil microbial biomass. AMF have been considered to be a tool to enhance phytoremediation, as their mycelium create a widespread underground network that acts as a bridge between plant roots, soil and rhizosphere microorganisms. Abundant extramatrical hyphae extend the rhizosphere thus creating the hyphosphere, which significantly increases the area of a plant's access to nutrients and contaminants. The paper presents and evaluates the role and significance of AMF in phytoremediation of hydrocarbon contaminated sites. We focused on (1) an impact of hydrocarbons on arbuscular mycorrhizal symbiosis, (2) a potential of AMF to enhance phytoremediation, (3) determinants that influence effectiveness of hydrocarbon removal from contaminated soils. This knowledge may be useful for selection of proper plant and fungal symbionts and crucial to optimize environmental conditions for effective AMF-mediated phytoremediation. It has been concluded that three-component phytoremediation systems based on synergistic interactions between plant roots, AMF and hydrocarbon-degrading microorganisms demonstrated high effectiveness in dissipation of organic pollutants in soil.
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Affiliation(s)
- Monika Rajtor
- Department of Microbiology, Faculty of Biology and Environmental Protection, University of Silesia, Jagiellońska Street 28, 40-032, Katowice, Poland.
| | - Zofia Piotrowska-Seget
- Department of Microbiology, Faculty of Biology and Environmental Protection, University of Silesia, Jagiellońska Street 28, 40-032, Katowice, Poland.
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Kumar A, Kumar S, Bains S, Vaidya V, Singh B, Kaur R, Kaur J, Singh K. De novo Transcriptome Analysis Revealed Genes Involved in Flavonoid and Vitamin C Biosynthesis in Phyllanthus emblica (L.). FRONTIERS IN PLANT SCIENCE 2016; 7:1610. [PMID: 27833630 PMCID: PMC5081490 DOI: 10.3389/fpls.2016.01610] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 10/12/2016] [Indexed: 05/05/2023]
Abstract
Phyllanthus emblica is an affluent source of various therapeutic components. A few of them like vitamin C and flavonoids are predominant bioactive compounds that are being used in immense pharmacological applications. In-spite of numerous applications, the genomic information of this plant was limited to a few expressed sequence tags (ESTs) in DNA databases. Herein, we developed in-depth transcriptome information of P. emblica using Illumina Hiseq 2000 platform and characterized. A total of 31,285,965 high-quality reads were assembled into 91,288 contigs with the N50 value 358. Out of them, 47,267 contigs were functionally annotated using BLASTX search against NCBI-non-redundant (NR) protein database. Further, 31,366 contigs showed similarity with various gene ontology (GO) terms, and 1299 were related to different enzymes and biosynthetic pathways. We identified the transcripts related to each gene involved in flavonoid and vitamin C biosynthesis. Several cytochrome P450s (CYPs) and glucosyltransferases (GTs) genes involved in flavonoid biosynthesis and various other metabolic pathways were also documented. Further, 6510 transcription factors and 4420 EST derived simple sequence repeat (SSR) markers were also predicted. The present study enlightened various characteristic features of P. emblica genome, and provided an important resource for future molecular and functional genomics studies.
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Affiliation(s)
| | | | | | | | | | | | | | - Kashmir Singh
- Department of Biotechnology, Panjab UniversityChandigarh, India
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54
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Esterhuizen-Londt M, Schwartz K, Pflugmacher S. Using aquatic fungi for pharmaceutical bioremediation: Uptake of acetaminophen by Mucor hiemalis does not result in an enzymatic oxidative stress response. Fungal Biol 2016; 120:1249-57. [DOI: 10.1016/j.funbio.2016.07.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 07/11/2016] [Accepted: 07/21/2016] [Indexed: 12/14/2022]
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Gworek B, Klimczak K, Kijeńska M, Gozdowski D. Comparison of PAHs uptake by selected Monocotyledones and Dicotyledones from municipal and industrial sewage sludge. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:19461-70. [PMID: 27381356 PMCID: PMC5031754 DOI: 10.1007/s11356-016-7130-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2015] [Accepted: 06/20/2016] [Indexed: 06/01/2023]
Abstract
The study was focused on two goals: (i) the confirmation of the existence of a general relation between the content of polycyclic aromatic hydrocarbons (PAHs) in sewage sludge and in plants growing in it, regardless of the type and content of sewage sludge, and (ii) if so, the answer to the question whether the uptake of PAHs by plants depends on their type. To realize the set aims, the contents of PAHs in four differentiated plant species were measured, two belonging to the Monocotyledones and two belonging to Dicotyledones group, growing in municipal and industrial sewage sludge in two locations. All the investigations were carried out during the period of 3 years. The results clearly demonstrated that the uptake of PAHs by a plant depended on polyaromatic hydrocarbon concentration in the sewage sludge. The relation between accumulation coefficient of PAHs in plant material vs. the content of PAH in sewage sludge was of exponential character. The results indicate that in case of four- and five-ring PAHs, the root uptake mechanism from soil solution occurs, regardless of the type and origin of sewage sludge and the type of plant. For three-ring PAHs, we can assume for Monocotyledones that the root uptake mechanism occurs because we observe a significant correlation between the content of fluorene, phenanthrene, and anthracene in plant material and in the sewage sludge. For Dicotyledones, the correlation is insignificant, and in this case probably two mechanisms occur-the uptake by roots and by leaves.
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Affiliation(s)
- Barbara Gworek
- National Research Institute, Institute of Environmental Protection, Krucza 5/11 d, Warsaw, Poland
| | - Katarzyna Klimczak
- Department of Soil Environment Sciences, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, Warsaw, Poland
| | - Marta Kijeńska
- National Research Institute, Institute of Environmental Protection, Krucza 5/11 d, Warsaw, Poland.
| | - Dariusz Gozdowski
- Department of Experimental Design and Bioinformatics, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, Warsaw, Poland
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56
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Pulido JMO. A review on the use of membrane technology and fouling control for olive mill wastewater treatment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 563-564:664-675. [PMID: 26472261 DOI: 10.1016/j.scitotenv.2015.09.151] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Revised: 09/29/2015] [Accepted: 09/29/2015] [Indexed: 06/05/2023]
Abstract
Olive mill effluents (OME) by-produced have significantly increased in the last decades as a result of the boost of the olive oil agro-industrial sector and due to the conversion into continuous operation centrifugation technologies. In these effluents, the presence of phytotoxic recalcitrant pollutants makes them resistant to biological degradation and thus inhibits the efficiency of biological and conventional processes. Many reclamation treatments as well as integrated processes for OME have already been proposed and developed but not led to completely satisfactory and cost-effective results. Olive oil industries in its current status, typically small mills dispersed, cannot afford such high treatment costs. Furthermore, conventional treatments are not able to abate the significant dissolved monovalent and divalent ions concentration present in OME. Within this framework, membrane technology offers high efficiency and moderate investment and maintenance expenses. Wastewater treatment by membrane technologies is growing in the recent years. This trend is owed to the fact of the availability of new membrane materials, membrane designs, membrane module concepts and general know-how, which have promoted credibility among investors. However, fouling reduces the membrane performances in time and leads to premature substitution of the membrane modules, and this is a problem of cost efficiency since wastewater treatment must imply low operating costs. Appropriate fouling inhibition methods should assure this result, thus making membrane processes for wastewater stream treatment both technically and economically feasible. In this paper, the treatment of the effluents by-produced in olive mills, generally called olive mill wastewaters, will be addressed. Within this context, the state of the art of the different pretreatments and integral membrane processes proposed up to today will be gathered and discussed, with an insight in the problem of fouling.
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Romão-Dumaresq AS, Dourado MN, Fávaro LCDL, Mendes R, Ferreira A, Araújo WL. Diversity of Cultivated Fungi Associated with Conventional and Transgenic Sugarcane and the Interaction between Endophytic Trichoderma virens and the Host Plant. PLoS One 2016; 11:e0158974. [PMID: 27415014 PMCID: PMC4944904 DOI: 10.1371/journal.pone.0158974] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 06/24/2016] [Indexed: 12/23/2022] Open
Abstract
Plant-associated fungi are considered a vast source for biotechnological processes whose potential has been poorly explored. The interactions and diversity of sugarcane, one of the most important crops in Brazil, have been rarely studied, mainly concerning fungal communities and their interactions with transgenic plants. Taking this into consideration, the purpose of this study was, based on culture dependent strategy, to determine the structure and diversity of the fungal community (root endophytes and rhizosphere) associated with two varieties of sugarcane, a non-genetically modified (SP80-1842) variety and its genetically modified counterpart (IMI-1, expressing imazapyr herbicide resistance). For this, the sugarcane varieties were evaluated in three sampling times (3, 10 and 17 months after planting) under two crop management (weeding and herbicide treatments). In addition, a strain of Trichoderma virens, an endophyte isolated from sugarcane with great potential as a biological control, growth promotion and enzyme production agent, was selected for the fungal-plant interaction assays. The results of the isolation, characterization and evaluation of fungal community changes showed that the sugarcane fungal community is composed of at least 35 different genera, mostly in the phylum Ascomycota. Many genera are observed at very low frequencies among a few most abundant genera, some of which were isolated from specific plant sites (e.g., the roots or the rhizosphere). An assessment of the possible effects upon the fungal community showed that the plant growth stage was the only factor that significantly affected the community's structure. Moreover, if transgenic effects are present, they may be minor compared to other natural sources of variation. The results of interaction studies using the Green fluorescent protein (GFP)-expressing T. virens strain T.v.223 revealed that this fungus did not promote any phenotypic changes in the host plant and was found mostly in the roots where it formed a dense mycelial cover and was able to penetrate the intercellular spaces of the root epidermis upper layers. The ability of T. virens to colonize plant roots suggests a potential for protecting plant health, inhibiting pathogens or inducing systemic resistance.
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Affiliation(s)
- Aline Silva Romão-Dumaresq
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
| | - Manuella Nóbrega Dourado
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Laboratory of Molecular Biology and Microbial Ecology, Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Léia Cecilia de Lima Fávaro
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, Brasília, Distrito Federal, Brazil
| | - Rodrigo Mendes
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Brazilian Agricultural Research Corporation, Embrapa Environment, Jaguariuna, São Paulo, Brazil
| | - Anderson Ferreira
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Brazilian Agricultural Research Corporation, Embrapa Agrosilvopastoral, Sinop, Mato Grosso, Brazil
| | - Welington Luiz Araújo
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Laboratory of Molecular Biology and Microbial Ecology, Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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58
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Shah BA, Abebe AA, Shah AV. Microwave-Synthesized Barium-Impregnated Siliceous Zeolitic Material Derived from Bagasse Fly Ash for Uptake of Aniline. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2016. [DOI: 10.1007/s13369-016-2083-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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59
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Zheng G, Chen T, Yu J, Gao D, Shen Y, Niu M, Liu H. Impact of composting strategies on the degradation of nonylphenol in sewage sludge. ECOTOXICOLOGY (LONDON, ENGLAND) 2015; 24:2081-2087. [PMID: 26452367 DOI: 10.1007/s10646-015-1558-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/24/2015] [Indexed: 06/05/2023]
Abstract
Nonylphenol can be present in sewage sludge, and this can limit the use of the sewage sludge to amend soil. Composting is one of the most efficient and economical methods of making sewage sludge stable and harmless. The nonylphenol degradation rates during composting with added bulking agents and with aeration applied were studied. Three organic bulking agents (sawdust, corn stalk, and mushroom residue) were added to sewage sludge, and the effects of the bulking agents used and the amount added on nonylphenol degradation were determined. The highest apparent nonylphenol degradation rate (71.6%) was found for sewage sludge containing 20% mushroom residue. The lowest apparent nonylphenol degradation rate (22.5%) was found for sewage sludge containing 20% sawdust. The temperature of the composting pile of sewage sludge containing 20% sawdust became too high for nonylphenol to be efficiently degraded, and the apparent nonylphenol degradation rate was lower than was found for sewage sludge containing 10% sawdust. Increasing the ventilating time from 5 to 15 min increased the apparent nonylphenol degradation rate from 19.7 to 41.6%. Using appropriate aerobic conditions facilitates the degradation of nonylphenol in sewage sludge, decreasing the risks posed by sewage sludge applied to land. Adding too much of a bulking agent can decrease the amount of the nonylphenol degraded. Increasing the ventilating time and the amount of air supplied can increase the amount of nonylphenol degraded even if doing so causes the composting pile temperature to remain low.
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Affiliation(s)
- Guodi Zheng
- Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Tongbin Chen
- Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Jie Yu
- Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Ding Gao
- Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yujun Shen
- Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Mingjie Niu
- Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Hongtao Liu
- Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
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60
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Kafilzadeh F, Khosrobak A, Jamali H. Isolation and Identification of Phenanthrene Degrading Bacteria from the Soil around Oil Company of Andimeshk and Investigation of Their Growth Kinetics. Polycycl Aromat Compd 2015. [DOI: 10.1080/10406638.2015.1037006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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61
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Ochando-Pulido JM, Martinez-Ferez A. On the Recent Use of Membrane Technology for Olive Mill Wastewater Purification. MEMBRANES 2015; 5:513-31. [PMID: 26426062 PMCID: PMC4703997 DOI: 10.3390/membranes5040513] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 09/24/2015] [Indexed: 12/03/2022]
Abstract
Many reclamation treatments as well as integrated processes for the purification of olive mill wastewaters (OMW) have already been proposed and developed but not led to completely satisfactory results, principally due to complexity or cost-ineffectiveness. The olive oil industry in its current status, composed of little and dispersed factories, cannot stand such high costs. Moreover, these treatments are not able to abate the high concentration of dissolved inorganic matter present in these highly polluted effluents. In the present work, a review on the actual state of the art concerning the treatment and disposal of OMW by membranes is addressed, comprising microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO), as well as membrane bioreactors (MBR) and non-conventional membrane processes such as vacuum distillation (VD), osmotic distillation (OD) and forward osmosis (FO). Membrane processes are becoming extensively used to replace many conventional processes in the purification of water and groundwater as well as in the reclamation of wastewater streams of very diverse sources, such as those generated by agro-industrial activities. Moreover, a brief insight into inhibition and control of fouling by properly-tailored pretreatment processes upstream the membrane operation and the use of the critical and threshold flux theories is provided.
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62
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Tomar RS, Sharma A, Jajoo A. Assessment of phytotoxicity of anthracene in soybean (Glycine max) with a quick method of chlorophyll fluorescence. PLANT BIOLOGY (STUTTGART, GERMANY) 2015; 17:870-6. [PMID: 25565351 DOI: 10.1111/plb.12302] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 12/19/2014] [Indexed: 05/05/2023]
Abstract
A decrease in photosynthetic efficiency may indicate the toxic effects of environmental pollutants on higher plants. Measurement of chlorophyll (Chl) a fluorescence to assess the performance of photosystem II (PSII) was used as an bioindicator of toxicity of the polycyclic aromatic hydrocarbon (PAH) anthracene (ANT) in soybean plants. The results revealed that ANT treatment caused a reduction in quantum yield of PSII, damage to the oxygen evolving complex, as well as a significant reduction in performance index of PSII. However, change in performance index was more prominent, and it seems that the performance index is a more sensitive parameter to environmental contaminants. Moreover, a change in heterogeneity of PSII was also observed. The number of active reaction centres decreased with increasing concentration of ANT, as secondary plastoquinone reducing centres were converted into non-reducing centres, and PSIIα centres were converted into PSIIβ and PSIIγ centres. The influence of ANT on PSII heterogeneity could be an important reason for reductions in the PSII performance.
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Affiliation(s)
- R S Tomar
- School of Life Science, Devi Ahilya University, Indore, India
| | - A Sharma
- School of Life Science, Devi Ahilya University, Indore, India
| | - A Jajoo
- School of Life Science, Devi Ahilya University, Indore, India
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63
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Shifts in Symbiotic Endophyte Communities of a Foundational Salt Marsh Grass following Oil Exposure from the Deepwater Horizon Oil Spill. PLoS One 2015; 10:e0122378. [PMID: 25923203 PMCID: PMC4414556 DOI: 10.1371/journal.pone.0122378] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 02/16/2015] [Indexed: 12/01/2022] Open
Abstract
Symbiotic associations can be disrupted by disturbance or by changing environmental conditions. Endophytes are fungal and bacterial symbionts of plants that can affect performance. As in more widely known symbioses, acute or chronic stressor exposure might trigger disassociation of endophytes from host plants. We tested this hypothesis by examining the effects of oil exposure following the Deepwater Horizon (DWH) oil spill on endophyte diversity and abundance in Spartina alterniflora – the foundational plant in northern Gulf coast salt marshes affected by the spill. We compared bacterial and fungal endophytes isolated from plants in reference areas to isolates from plants collected in areas with residual oil that has persisted for more than three years after the DWH spill. DNA sequence-based estimates showed that oil exposure shifted endophyte diversity and community structure. Plants from oiled areas exhibited near total loss of leaf fungal endophytes. Root fungal endophytes exhibited a more modest decline and little change was observed in endophytic bacterial diversity or abundance, though a shift towards hydrocarbon metabolizers was found in plants from oiled sites. These results show that plant-endophyte symbioses can be disrupted by stressor exposure, and indicate that symbiont community disassembly in marsh plants is an enduring outcome of the DWH spill.
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64
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Balasubramaniyam A, Harvey PJ. Changes in the abundance of sugars and sugar-like compounds in tall fescue (Festuca arundinacea) due to growth in naphthalene-treated sand. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:5817-5830. [PMID: 25391233 DOI: 10.1007/s11356-014-3812-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 11/03/2014] [Indexed: 06/04/2023]
Abstract
The hydrophilic metabolome of tall fescue (Festuca arundinacea) adapted to grow in naphthalene-treated sand (0.8 g kg(-1) sand dw) was analysed using gas chromatography-mass spectrometry, and peaks corresponding to the more abundant compounds were tentatively identified from analysis of their mass spectral features and reference to the NIST Mass Spectral Database. Particular attention was paid to sugars as they are known to play important roles as stress regulators in plants. The results showed that the abundance of sugars was greater in the roots but lesser in the shoots of treated plants when compared to their control counterparts. The results for indole acetic acid (IAA) were notable: IAA was prominently less in the treated roots compared to shoots, and in treated shoots, IAA was particularly subdued compared to untreated shoots consistent with IAA degradation in treated plant tissues. The differences in the molecular phenotype between control and treated plants were expressed in root structural differences. The treated roots were modified to have greater suberisation, enhanced thickening in the endodermis and distortions in the cortical zone as demonstrated through scanning electron and epi-fluorescence microscopy.
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65
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Effect of rhizosphere enzymes on phytoremediation in PAH-contaminated soil using five plant species. PLoS One 2015; 10:e0120369. [PMID: 25822167 PMCID: PMC4378954 DOI: 10.1371/journal.pone.0120369] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2014] [Accepted: 02/09/2015] [Indexed: 11/19/2022] Open
Abstract
A pot experiment was performed to study the effectiveness of remediation using different plant species and the enzyme response involved in remediating PAH-contaminated soil. The study indicated that species Echinacea purpurea, Festuca arundinacea Schred, Fire Phoenix (a combined F. arundinacea), and Medicago sativa L. possess the potential for remediation in PAH-contaminated soils. The study also determined that enzymatic reactions of polyphenol oxidase (except Fire Phoenix), dehydrogenase (except Fire Phoenix), and urease (except Medicago sativa L.) were more prominent over cultivation periods of 60d and 120d than 150d. Urease activity of the tested species exhibited prominently linear negative correlations with alkali-hydrolyzable nitrogen content after the tested plants were cultivated for 150d (R2 = 0.9592). The experiment also indicated that alkaline phosphatase activity in four of the five tested species (Echinacea purpurea, Callistephus chinensis, Festuca arundinacea Schred and Fire Phoenix) was inhibited during the cultivation process (at 60d and 120d). At the same time, the study determined that the linear relationship between alkaline phosphatase activity and effective phosphorus content in plant rhizosphere soil exhibited a negative correlation after a growing period of 120d (R2 = 0.665). Phytoremediation of organic contaminants in the soil was closely related to specific characteristics of particular plant species, and the catalyzed reactions were the result of the action of multiple enzymes in the plant rhizosphere soil.
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66
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Bisht S, Pandey P, Bhargava B, Sharma S, Kumar V, Sharma KD. Bioremediation of polyaromatic hydrocarbons (PAHs) using rhizosphere technology. Braz J Microbiol 2015; 46:7-21. [PMID: 26221084 PMCID: PMC4512045 DOI: 10.1590/s1517-838246120131354] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Accepted: 06/06/2014] [Indexed: 11/26/2022] Open
Abstract
The remediation of polluted sites has become a priority for society because of increase in quality of life standards and the awareness of environmental issues. Over the past few decades there has been avid interest in developing in situ strategies for remediation of environmental contaminants, because of the high economic cost of physicochemical strategies, the biological tools for remediation of these persistent pollutants is the better option. Major foci have been considered on persistent organic chemicals i.e. polyaromatic hydrocarbons (PAHs) due to their ubiquitous occurrence, recalcitrance, bioaccumulation potential and carcinogenic activity. Rhizoremediation, a specific type of phytoremediation that involves both plants and their associated rhizospheric microbes is the creative biotechnological approach that has been explored in this review. Moreover, in this review we showed the significance of rhizoremediation of PAHs from other bioremediation strategies i.e. natural attenuation, bioaugmentation and phytoremediation and also analyze certain environmental factor that may influence the rhizoremediation technique. Numerous bacterial species were reported to degrade variety of PAHs and most of them are isolated from contaminated soil, however few reports are available from non contaminated soil. Pseudomonas aeruginosa , Pseudomons fluoresens , Mycobacterium spp., Haemophilus spp., Rhodococcus spp., Paenibacillus spp. are some of the commonly studied PAH-degrading bacteria. Finally, exploring the molecular communication between plants and microbes, and exploiting this communication to achieve better results in the elimination of contaminants, is a fascinating area of research for future perspective.
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Affiliation(s)
- Sandeep Bisht
- Department of Molecular Biology and Biotechnology, VCSG College of Horticulture, Uttarakhand University of Horticulture & Forestry, Uttarakhand, India
| | - Piyush Pandey
- Department of Microbiology, Assam University, Silchar, India
| | - Bhavya Bhargava
- Department of Floriculture & Landscaping Architecture, VCSG College of Horticulture, Uttarakhand University of Horticulture & Forestry, Uttarakhand, India
| | - Shivesh Sharma
- Department of Biotechnology, National Institute of Technology, Allahabad, India
| | - Vivek Kumar
- Amity Institutite of Microbial Technology, Amity Univeristy, Noida, India
| | - Krishan D. Sharma
- VCSG College of Horticulture, Uttarakhand University of Horticulture & Forestry, Uttarakhand, India
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Liu H, Weisman D, Tang L, Tan L, Zhang WK, Wang ZH, Huang YH, Lin WX, Liu XM, Colón-Carmona A. Stress signaling in response to polycyclic aromatic hydrocarbon exposure in Arabidopsis thaliana involves a nucleoside diphosphate kinase, NDPK-3. PLANTA 2015; 241:95-107. [PMID: 25224398 DOI: 10.1007/s00425-014-2161-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 08/22/2014] [Indexed: 05/18/2023]
Abstract
The study is the first to reveal the proteomic response in plants to a single PAH stress, and indicates that NDPK3 is a positive regulator in the Arabidopsis response to phenanthrene stress. Polycyclic aromatic hydrocarbons (PAHs) are highly carcinogenic pollutants that are byproducts of carbon-based fuel combustion, and tend to persist in the environment for long periods of time. PAHs elicit complex, damaging responses in plants, and prior research at the physiological, biochemical, and transcriptional levels has indicated that reactive oxygen species (ROS) and oxidative stress play major roles in the PAH response. However, the proteomic response has remained largely unexplored. This study hypothesized that the proteomic response in Arabidopsis thaliana to phenanthrene, a model PAH, would include a strong oxidative stress signature, and would provide leads to potential signaling molecules involved. To explore that proteomic signature, we performed 2D-PAGE experiments and identified 30 proteins levels that were significantly altered including catalases (CAT), ascorbate peroxidase (APX), peroxiredoxins (POD), glutathione-S-transferase, and glutathione reductase. Also upregulated was nucleoside diphosphate kinase 3 (NDPK-3), a protein known to have metabolic and stress signaling functions. To address whether NDPK-3 functions upstream of the oxidative stress response, we measured levels of stress-responsive enzymes in NDPK-3 overexpressor, loss-of-function knockout, and wild-type plant lines. In the NDPK-3 overexpressor, the enzyme activities of APX, CAT, POD, as well as superoxide dismutase were all increased compared to wild type; in the NDPK-3 knockout line, these enzymes had reduced activity. This pattern occurred in untreated as well as phenanthrene-treated plants. These data support a model in which NDPK-3 is a positive regulator of the Arabidopsis stress response to PAHs.
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Affiliation(s)
- Hong Liu
- College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China,
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68
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Baruah P, Saikia RR, Baruah PP, Deka S. Effect of crude oil contamination on the chlorophyll content and morpho-anatomy of Cyperus brevifolius (Rottb.) Hassk. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:12530-12538. [PMID: 24946711 DOI: 10.1007/s11356-014-3195-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 06/11/2014] [Indexed: 06/03/2023]
Abstract
Chlorophyll plays a pivotal role in the plant physiology and its productivity. Cultivation of plants in crude oil contaminated soil has a great impact on the synthesis of chlorophyll pigment. Morpho-anatomy of the experimental plant also shows structural deformation in higher concentrations. Keeping this in mind, a laboratory investigation has been carried out to study the effect of crude oil on chlorophyll content and morpho-anatomy of Cyperus brevifolius plant. Fifteen-day-old seedling of the plant was planted in different concentrations of the crude oil mixed soil (i.e., 10,000, 20,000, 30,000, 40,000, and 50,000 ppm). A control setup was also maintained without adding crude oil. Results were recorded after 6 months of plantation. Investigation revealed that there is a great impact of crude oil contamination on chlorophyll content of the leaves of the experimental plant. It also showed that chlorophyll a, chlorophyll b, and total chlorophyll content of leaves grown in different concentrations of crude oil were found to be lower than those of the control plant. Further, results also demonstrated that chlorophyll content was lowest in the treatment that received maximum dose of crude oil. It also showed that chlorophyll content was decreased with increased concentration of crude oil. Results also demonstrated that there was a reduction in plant shoot and root biomass with the increase of crude oil concentration. Results also revealed that the shoot biomass is higher than root biomass. Morphology and anatomy of the experimental plant also show structural deformation in higher concentrations. Accumulation of crude oil on the cuticle of the transverse section of the leaves and shoot forms a thick dark layer. Estimation of the level of pollution in an environment due to oil spill is possible by the in-depth study of the harmful effects of oil on the morphology and anatomy and chlorophyll content of the plants grown in that particular environment.
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Affiliation(s)
- Plabita Baruah
- Environmental Biotechnology Laboratory, Life Sciences Division, Institute of Advanced Study in Science and Technology (IASST), Paschim Boragaon, Guwahati, 781 035, Assam, India
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69
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Balasubramaniyam A, Harvey PJ. Scanning electron microscopic investigations of root structural modifications arising from growth in crude oil-contaminated sand. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:12651-12661. [PMID: 24958531 DOI: 10.1007/s11356-014-3138-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Accepted: 06/02/2014] [Indexed: 06/03/2023]
Abstract
The choice of plant for phytoremediation success requires knowledge of how plants respond to contaminant exposure, especially their roots which are instrumental in supporting rhizosphere activity. In this study, we investigated the responses of plants with different architectures represented by beetroot (Beta vulgaris), a eudicot with a central taproot and many narrower lateral roots, and tall fescue (Festuca arundinacea), a monocot possessing a mass of threadlike fibrous roots to grow in crude oil-treated sand. In this paper, scanning electron microscopy was used to investigate modifications to plant root structure caused by growth in crude oil-contaminated sand. Root structural disorders were evident and included enhanced thickening in the endodermis, increased width of the root cortical zone and smaller diameter of xylem vessels. Inhibition in the rate of root elongation correlated with the increase in cell wall thickening and was dramatically pronounced in beetroot compared to the roots of treated fescue. The latter possessed significantly fewer (p < 0.001) and significantly shorter (p < 0.001) root hairs compared to control plants. Possibly, root hairs that absorb the hydrophobic contaminants may prevent contaminant absorption into the main root and concomitant axile root thickening by being sloughed off from roots. Tall fescue exhibited greater root morphological adaptability to growth in crude oil-treated sand than beetroot and, thus, a potential for long-term phytoremediation.
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70
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Gworek B, Klimczak K, Kijeńska M. The relation between polyaromatic hydrocarbon concentration in sewage sludge and its uptake by plants: Phragmites communis, Polygonum persicaria and Bidens tripartita. PLoS One 2014; 9:e109548. [PMID: 25310699 PMCID: PMC4195666 DOI: 10.1371/journal.pone.0109548] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 09/03/2014] [Indexed: 11/18/2022] Open
Abstract
The aim of the study was to define the relationship between the concentration of PAHs in sewage sludge at a particular location and their amount in various plant materials growing on it. The credibility of the results is enhanced by the fact that sewage sludge from two separate sewage-treatment plants were selected for their influence on the content of PAHs in three plant species growing on them. The investigations were carried out for a period of three years. The results demonstrated unequivocally that the uptake of PAHs by a plant depended on polyaromatic hydrocarbon concentration in the sewage sludge. The correlation between accumulation coefficient of PAH in a plant and the content of the same PAH in the sewage sludge had for three-, four- and five-ring hydrocarbons an exponential character and for six-ring hydrocarbons was of a linear character. The accumulation coefficients calculated for three-ring aromatics were several times higher than for four-ring PAHs; further the coefficient values calculated for five-ring PAHs were several times lower than for four-ring hydrocarbons. Finally, the accumulation coefficient values of six-ring PAHs were the lowest in the series of studied polyaromatic hydrocarbons.
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Affiliation(s)
- Barbara Gworek
- Institute of Environmental Protection – National Research Institute, Warsaw, Poland
| | - Katarzyna Klimczak
- Warsaw University of Life Sciences – SGGW, Department of Soil Environment Sciences, Warsaw, Poland
| | - Marta Kijeńska
- Institute of Environmental Protection – National Research Institute, Warsaw, Poland
- * E-mail:
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71
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Bramley-Alves J, Wasley J, King CK, Powell S, Robinson SA. Phytoremediation of hydrocarbon contaminants in subantarctic soils: an effective management option. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2014; 142:60-69. [PMID: 24836716 DOI: 10.1016/j.jenvman.2014.04.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 04/16/2014] [Accepted: 04/21/2014] [Indexed: 06/03/2023]
Abstract
Accidental fuel spills on world heritage subantarctic Macquarie Island have caused considerable contamination. Due to the island's high latitude position, its climate, and its fragile ecosystem, traditional methods of remediation are unsuitable for on-site clean up. We investigated the tolerance of a subantarctic native tussock grass, Poa foliosa (Hook. f.), to Special Antarctic Blend (SAB) diesel fuel and its potential to reduce SAB fuel contamination via phytoremediation. Toxicity of SAB fuel to P. foliosa was assessed in an 8 month laboratory growth trial under growth conditions which simulated the island's environment. Single seedlings were planted into 1 L pots of soil spiked with SAB fuel at concentrations of 1000, 5 000, 10,000, 2000 and 40,000 mg/kg (plus control). Plants were harvested at 0, 2, 4 and 8 months and a range of plant productivity endpoints were measured (biomass production, plant morphology and photosynthetic efficiency). Poa foliosa was highly tolerant across all SAB fuel concentrations tested with respect to biomass, although higher concentrations of 20,000 and 40,000 mg SAB/kg soil caused slight reductions in leaf length, width and area. To assess the phytoremediation potential of P. foliosa (to 10 000 mg/kg), soil from the planted pots was compared with that from paired unplanted pots at each SAB fuel concentration. The effect of the plant on SAB fuel concentrations and the associated microbial communities found within the soil (total heterotrophs and hydrocarbon degraders) were compared between planted and unplanted treatments at the 0, 2, 4 and 8 month harvest periods. The presence of plants resulted in significantly less SAB fuel in soils at 2 months and a return to background concentration by 8 months. Microbes did not appear to be the sole driving force behind the observed hydrocarbon loss. This study provides evidence that phytoremediation using P. foliosa is a valuable remediation option for use at Macquarie Island, and may be applicable to the management of fuel spills in other cold climate regions.
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Affiliation(s)
- Jessica Bramley-Alves
- Institute of Conservation Biology and Environmental Management, School of Biological Sciences, University of Wollongong, NSW 2522, Australia.
| | - Jane Wasley
- Australian Antarctic Division, Department of Sustainability, Environment, Water, Population and Communities, 203 Channel Highway, Kingston 7050, Australia
| | - Catherine K King
- Australian Antarctic Division, Department of Sustainability, Environment, Water, Population and Communities, 203 Channel Highway, Kingston 7050, Australia
| | - Shane Powell
- Tasmanian Institute of Agriculture, University of Tasmania, Private Bag 54, Hobart 7001, Australia
| | - Sharon A Robinson
- Institute of Conservation Biology and Environmental Management, School of Biological Sciences, University of Wollongong, NSW 2522, Australia
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72
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Malchi T, Maor Y, Tadmor G, Shenker M, Chefetz B. Irrigation of root vegetables with treated wastewater: evaluating uptake of pharmaceuticals and the associated human health risks. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:9325-33. [PMID: 25026038 DOI: 10.1021/es5017894] [Citation(s) in RCA: 241] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
To meet mounting water demands, treated wastewater has become an important source of irrigation. Thus, contamination of treated wastewater by pharmaceutical compounds (PCs) and the fate of these compounds in the agricultural environment are of increasing concern. This field study aimed to quantify PC uptake by treated wastewater-irrigated root crops (carrots and sweet potatoes) grown in lysimeters and to evaluate potential risks. In both crops, the nonionic PCs (carbamazepine, caffeine, and lamotrigine) were detected at significantly higher concentrations than ionic PCs (metoprolol, bezafibrate, clofibric acid, diclofenac, gemfibrozil, ibuprofen, ketoprofen, naproxen, sulfamethoxazole, and sildenafil). PCs in leaves were found at higher concentrations than in the roots. Carbamazepine metabolites were found mainly in the leaves, where the concentration of the metabolite 10,11-epoxycarbamazepine was significantly higher than the parent compound. The health risk associated with consumption of wastewater-irrigated root vegetables was estimated using the threshold of toxicological concern (TTC) approach. Our data show that the TTC value of lamotrigine can be reached for a child at a daily consumption of half a carrot (∼60 g). This study highlights that certain PCs accumulated in edible organs at concentrations above the TTC value should be categorized as contaminants of emerging concern.
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Affiliation(s)
- Tomer Malchi
- Department of Soil and Water Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem , Rehovot 76100, Israel
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73
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Goldstein M, Shenker M, Chefetz B. Insights into the uptake processes of wastewater-borne pharmaceuticals by vegetables. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:5593-600. [PMID: 24749778 DOI: 10.1021/es5008615] [Citation(s) in RCA: 190] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
An increasing number of reports on plant uptake of pharmaceutical compounds (PCs) have been recently published, raising concerns of human exposure through dietary intake. In this study, PC uptake and translocation were evaluated in cucumber and tomato plants to elucidate the effects of PC physicochemical properties, soil type, and irrigation-water quality. Nonionic PCs were taken up and accumulated at higher levels in plants grown in soils of lower organic matter and clay content. While the concentration of most PCs in cucumber and tomato leaves were of similar order, their concentrations in the tomato fruit were much lower than in the cucumber fruit. This is related to differences in fruit physiology. Our data suggest that irrigation with treated wastewater reduces the bioavailability of acidic PCs for uptake by cucumber plants as compared to fresh water irrigation. This study sheds light on factors affecting the uptake of PCs by crops irrigated with treated wastewater, the governing role of PCs' physicochemical properties along with the physiological nature of the plant, soil properties and water quality that together determine uptake, translocation, and accumulation within plant organs. Occurrence of metabolites in plant suggests that PC metabolism has to be evaluated to reveal the total uptake.
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Affiliation(s)
- Myah Goldstein
- Department of Soil and Water Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem , Rehovot 76100, Israel
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74
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Martin BC, George SJ, Price CA, Ryan MH, Tibbett M. The role of root exuded low molecular weight organic anions in facilitating petroleum hydrocarbon degradation: current knowledge and future directions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 472:642-653. [PMID: 24317170 DOI: 10.1016/j.scitotenv.2013.11.050] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 11/10/2013] [Accepted: 11/10/2013] [Indexed: 05/28/2023]
Abstract
Rhizoremediation is a bioremediation technique whereby enhanced microbial degradation of organic contaminants occurs within the plant root zone (rhizosphere). It is considered an effective and affordable 'green technology' for remediating soils contaminated with petroleum hydrocarbons (PHCs). This paper critically reviews the potential role of root exuded compounds in rhizoremediation, with emphasis on commonly exuded low molecular weight aliphatic organic acid anions (carboxylates). The extent to which remediation is achieved shows wide disparity among plant species. Therefore, plant selection is crucial for the advancement and widespread adoption of this technology. Root exudation is speculated to be one of the predominant factors leading to microbial changes in the rhizosphere and thus the potential driver behind enhanced petroleum biodegradation. Carboxylates can form a significant component of the root exudate mixture and are hypothesised to enhance petroleum biodegradation by: i) providing an easily degradable energy source; ii) increasing phosphorus supply; and/or iii) enhancing the contaminant bioavailability. These differing hypotheses, which are not mutually exclusive, require further investigation to progress our understanding of plant-microbe interactions with the aim to improve plant species selection and the efficacy of rhizoremediation.
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Affiliation(s)
- Belinda C Martin
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Suman J George
- School of Earth and Environment, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Charles A Price
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Megan H Ryan
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Mark Tibbett
- School of Earth and Environment, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; Department of Environmental Science and Technology, Cranfield University, College Road, Bedfordshire, MK43 0AL England, United Kingdom.
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75
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Masciandaro G, Di Biase A, Macci C, Peruzzi E, Iannelli R, Doni S. Phytoremediation of dredged marine sediment: monitoring of chemical and biochemical processes contributing to sediment reclamation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2014; 134:166-174. [PMID: 24486533 DOI: 10.1016/j.jenvman.2013.12.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 12/23/2013] [Accepted: 12/27/2013] [Indexed: 06/03/2023]
Abstract
In this study, a pilot phytoremediation experiment was performed to treat about 80 m(3) of silty saline sediments contaminated by heavy metals and organic compounds. After preliminary mixing with a sandy soil and green compost application, three different plant treatments [Paspalum vaginatum (P); P. vaginatum + Spartium junceum (P + S); P. vaginatum + Tamarix gallica (P + T)] were compared to each other and to an unplanted control (C) in order to evaluate the plant efficiency in remediating and ameliorating agronomical and functional sediment properties. The experiment was monitored for one year after planting by taking sediment samples at two depths and performing several chemical and biochemical analyses. After one year, the increase in hydrolytic enzyme and dehydrogenase activities indicated the stimulation of sediment functionality. Additionally, the availability of energy sources derived from organic matter application and plant-root activity promoted the formation of a stable organic matter fraction. Finally, P + S and P + T were also effective in decontaminating polluted marine sediments from both organic (total petroleum hydrocarbons, TPH) and inorganic (heavy metal) pollutants.
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Affiliation(s)
- G Masciandaro
- National Research Council, Institute of Ecosystem Study, Via Moruzzi 1, 56124 Pisa, Italy
| | - A Di Biase
- National Research Council, Institute of Ecosystem Study, Via Moruzzi 1, 56124 Pisa, Italy
| | - C Macci
- National Research Council, Institute of Ecosystem Study, Via Moruzzi 1, 56124 Pisa, Italy
| | - E Peruzzi
- National Research Council, Institute of Ecosystem Study, Via Moruzzi 1, 56124 Pisa, Italy
| | - R Iannelli
- University of Pisa, Department of Engineering for Energy, Systems, Territory and Constructions, Via Gabba 22, 56122 Pisa, Italy
| | - S Doni
- National Research Council, Institute of Ecosystem Study, Via Moruzzi 1, 56124 Pisa, Italy.
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Ouvrard S, Leglize P, Morel JL. PAH phytoremediation: rhizodegradation or rhizoattenuation? INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2014; 16:46-61. [PMID: 24912214 DOI: 10.1080/15226514.2012.759527] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Dealing with soil contaminated with persistent organic pollutants (POP) is an increasing concern amplified by both regulatory constraints and the dramatic impact of human activities on the soil resource. The most used management options are treatments which totally eradicate the toxic compounds targeted. When possible, environmental-friendly processes should be used, and recent years have seen the emergence of green technologies using biological energies involving microorganisms (bioremediation) and plants (phytoremediation). Research has focused on phytoremediation and many have presented this technology as the process ideally combining efficiency, low cost and environmental acceptance. However, the applicability of phytoremediation on soils contaminated by bio-recalcitrant organic compounds, such as polycyclic aromatic hydrocarbons (PAH), has not yet proved as successful as expected. We propose here a review and discussion of the overall question of PAH status in soil and their potential for treatment. The limits and applicability of bioremediation technologies are discussed, and the specific beneficial effect of plants is objectively evaluated with a special interest to processes which lead to rhizoattenuation. Given the PAH high affinity to soil organic matter, availability is the main limitation to phytoremediation. In this context, bioavailability quantification remains an issue as well as the characterization of the recalcitrant fraction.
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Hechmi N, Aissa NB, Abdenaceur H, Jedidi N. Phytoremediation efficiency of a pcp-contaminated soil using four plant species as mono- and mixed cultures. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2014; 16:1241-1256. [PMID: 24933915 DOI: 10.1080/15226514.2013.828009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Bioremediation of soil polluted by pentachlorophenol (PCP) is of great importance due to the persistence and carcinogenic properties of PCP. Phytoremediation has long been recognized as a promising approach for removal of PCP from soil. The present study was conducted to investigate the capability of four plant species; white clover, ryegrass, alfalfa, and rapeseed grown alone and in combination to remediate pentachlorophenol contaminated soil. After 60 days cultivation, white clover, raygrass, alfalfa, and rapeseed all significantly enhanced the degradation of PCP in soils. Alfalfa showed highest efficiency for the removal of PCP in single cropping flowed by rapeseed and ryegrass. Mixed cropping significantly enhanced the remediation efficiencies as compared to single cropping; about 89.84% of PCP was removed by mixed cropping of rapeseed and alfalfa, and 72.01% of PCP by mixed cropping of rape and white clover. Mixed cropping of rapeseed with alfalfa was however far better for the remediation of soil PCP than single cropping. An evaluation of soil biological activities as a monitoring mechanism for the bioremediation process of a PCP-contaminated soil was made using measurements of microbial counts and dehydrogenase activity.
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Aranda E, Scervino JM, Godoy P, Reina R, Ocampo JA, Wittich RM, García-Romera I. Role of arbuscular mycorrhizal fungus Rhizophagus custos in the dissipation of PAHs under root-organ culture conditions. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2013; 181:182-9. [PMID: 23867699 DOI: 10.1016/j.envpol.2013.06.034] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 06/18/2013] [Accepted: 06/19/2013] [Indexed: 05/10/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are one of the most common contaminants in soil. Arbuscular mycorrhizal (AM) fungi make host plants resistant to pollutants. This study aims to evaluate the impact of anthracene, phenanthrene and dibenzothiophene on the AM fungus Rhizophagus custos, isolated from soil contaminated by heavy metals and PAHs, under monoxenic conditions. We found a high level of tolerance in R. custos to the presence of PAHs, especially in the case of anthracene, in which no negative effect on AM-colonized root dry weight (root yield) was observed, and also a decrease in the formation of anthraquinone was detected. Increased PAH dissipation in the mycorrhizal root culture medium was observed; however, dissipation was affected by the level of concentration and the specific PAH, which lead us to a better understanding of the possible contribution of AM fungi, and in particular R. custos, to pollutant removal.
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Affiliation(s)
- Elisabet Aranda
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín, CSIC, Profesor Albareda No. 1, 18008 Granada, Spain.
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Biotransformation of Trichoderma spp. and their tolerance to aromatic amines, a major class of pollutants. Appl Environ Microbiol 2013; 79:4719-26. [PMID: 23728813 DOI: 10.1128/aem.00989-13] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Trichoderma spp. are cosmopolitan soil fungi that are highly resistant to many toxic compounds. Here, we show that Trichoderma virens and T. reesei are tolerant to aromatic amines (AA), a major class of pollutants including the highly toxic pesticide residue 3,4-dichloroaniline (3,4-DCA). In a previous study, we provided proof-of-concept remediation experiments in which another soil fungus, Podospora anserina, detoxifies 3,4-DCA through its arylamine N-acetyltransferase (NAT), a xenobiotic-metabolizing enzyme that enables acetyl coenzyme A-dependent detoxification of AA. To assess whether the N-acetylation pathway enables AA tolerance in Trichoderma spp., we cloned and characterized NATs from T. virens and T. reesei. We characterized recombinant enzymes by determining their catalytic efficiencies toward several toxic AA. Through a complementary approach, we also demonstrate that both Trichoderma species efficiently metabolize 3,4-DCA. Finally, we provide evidence that NAT-independent transformation is solely (in T. virens) or mainly (in T. reesei) responsible for the observed removal of 3,4-DCA. We conclude that T. virens and, to a lesser extent, T. reesei likely utilize another, unidentified, metabolic pathway for the detoxification of AA aside from acetylation. This is the first molecular and functional characterization of AA biotransformation in Trichoderma spp. Given the potential of Trichoderma for cleanup of contaminated soils, these results reveal new possibilities in the fungal remediation of AA-contaminated soil.
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Sirguey C, Ouvrard S. Contaminated soils salinity, a threat for phytoextraction? CHEMOSPHERE 2013; 91:269-274. [PMID: 23245576 DOI: 10.1016/j.chemosphere.2012.11.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Revised: 11/05/2012] [Accepted: 11/14/2012] [Indexed: 06/01/2023]
Abstract
Phytoremediation, given the right choice of plant, may be theoretically applicable to multi-contamination. Laboratory and some field trials have proven successful, but this ideal technique is in all cases dependent on plant growth ability on (generally) low-fertility soil or media. While contaminant concentration has often been proposed as an explanation for plant growth limitation, other factors, commonly occurring in industrial soils, such as salinity, should be considered. The present work highlights the fact that besides contaminants (trace elements and PAH), soil salinity may strongly affect germination and growth of the hyperaccumulator Noccaea caerulescens. Elevated concentrations of nitrate proved highly toxic for seed germination. At the growth stage the salt effect (sulfate) seemed less significant and the limited biomass production observed could be attributed mostly to organic contamination.
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Affiliation(s)
- Catherine Sirguey
- Université de Lorraine, LSE, UMR 1120, Vandœuvre-lès-Nancy F-54505, France.
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81
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Khan S, Afzal M, Iqbal S, Khan QM. Plant-bacteria partnerships for the remediation of hydrocarbon contaminated soils. CHEMOSPHERE 2013; 90:1317-32. [PMID: 23058201 DOI: 10.1016/j.chemosphere.2012.09.045] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 09/08/2012] [Accepted: 09/10/2012] [Indexed: 05/06/2023]
Abstract
Plant-bacteria partnerships have been extensively studied and applied to improve crop yield. In addition to their application in agriculture, a promising field to exploit plant-bacteria partnerships is the remediation of soil and water polluted with hydrocarbons. Application of effective plant-bacteria partnerships for the remediation of hydrocarbons depend mainly on the presence and metabolic activities of plant associated rhizo- and endophytic bacteria possessing specific genes required for the degradation of hydrocarbon pollutants. Plants and their associated bacteria interact with each other whereby plant supplies the bacteria with a special carbon source that stimulates the bacteria to degrade organic contaminants in the soil. In return, plant associated-bacteria can support their host plant to overcome contaminated-induced stress responses, and improve plant growth and development. In addition, plants further get benefits from their associated-bacteria possessing hydrocarbon-degradation potential, leading to enhanced hydrocarbon mineralization and lowering of both phytotoxicity and evapotranspiration of volatile hydrocarbons. A better understanding of plant-bacteria partnerships could be exploited to enhance the remediation of hydrocarbon contaminated soils in conjunction with sustainable production of non-food crops for biomass and biofuel production.
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Affiliation(s)
- Sumia Khan
- National Institute for Biotechnology and Genetic Engineering, Faisalabad, Pakistan
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82
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Ahmad F, Iqbal S, Anwar S, Afzal M, Islam E, Mustafa T, Khan QM. Enhanced remediation of chlorpyrifos from soil using ryegrass (Lollium multiflorum) and chlorpyrifos-degrading bacterium Bacillus pumilus C2A1. JOURNAL OF HAZARDOUS MATERIALS 2012; 237-238:110-115. [PMID: 22959266 DOI: 10.1016/j.jhazmat.2012.08.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Revised: 07/16/2012] [Accepted: 08/02/2012] [Indexed: 05/28/2023]
Abstract
The combined use of plants and associated microorganisms has great potential for remediating soil contaminated with organic compounds such as pesticides. The objective of this study was to determine whether the bacterial inoculation influences plant growth promotion and chlorpyrifos (CP) degradation and accumulation in different parts of the plant. Ryegrass was grown in soil spiked with CP and inoculated with a pesticide degrading bacterial strain Bacillus pumilus C2A1. Inoculation generally had a beneficial effect on CP degradation and plant biomass production, highest CP degradation (97%) was observed after 45 days of inoculation. Furthermore, inoculated strain efficiently colonized in the rhizosphere of inoculated plant and enhanced CP and its primary metabolite 3,5,6-trichloro-2-pyridinol (TCP) degradation. There was significantly less CP accumulation in roots and shoots of inoculated plants as compared to uninoculated plants. The results show the effectiveness of inoculated exogenous bacteria to boost the remediation of CP contaminated sites and decrease levels of toxic pesticide residues in crop plants.
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Affiliation(s)
- Fiaz Ahmad
- Environmental Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box 577, Jhang Road Faisalabad, Pakistan
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83
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Identification of genes differentially expressed in the roots of rubber tree (Hevea brasiliensis Muell. Arg.) in response to phosphorus deficiency. Mol Biol Rep 2012; 40:1397-405. [PMID: 23076531 DOI: 10.1007/s11033-012-2183-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Accepted: 10/09/2012] [Indexed: 10/27/2022]
Abstract
Phosphorus (P) is an essential macronutrient for plant growth and development. P deficiency could affect rubber tree productivity seriously, and understanding the mechanism responses of the rubber tree under the P deficiency will be helpful to improving rubber tree productivity. The molecular mechanism by which the rubber trees respond to a P-deficiency is a complex network involving many processes. To identify the genes differentially expressed in that response, we constructed subtractive suppression hybridization libraries for roots of plants growing under deficient or sufficient conditions. We identified 94 up-regulated genes from the forward library and 45 down-regulated from the reverse library. These differentially expressed genes were categorized into eight groups representing functions in metabolism, transcription, signal transduction, protein synthesis, transport, stress responses, photosynthesis, and development. We also performed quantitative real-time PCR to investigate the expression profiles of eight randomly selected clones. Our results provide useful information for further study of the molecular mechanism for adaptations to a P-deficiency in this species. Further characterization and functional analysis of these differentially expressed genes will help us improve its phosphorus utilization and overall productivity.
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84
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Beazley MJ, Martinez RJ, Rajan S, Powell J, Piceno YM, Tom LM, Andersen GL, Hazen TC, Van Nostrand JD, Zhou J, Mortazavi B, Sobecky PA. Microbial community analysis of a coastal salt marsh affected by the Deepwater Horizon oil spill. PLoS One 2012; 7:e41305. [PMID: 22815990 PMCID: PMC3399869 DOI: 10.1371/journal.pone.0041305] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 06/19/2012] [Indexed: 11/30/2022] Open
Abstract
Coastal salt marshes are highly sensitive wetland ecosystems that can sustain long-term impacts from anthropogenic events such as oil spills. In this study, we examined the microbial communities of a Gulf of Mexico coastal salt marsh during and after the influx of petroleum hydrocarbons following the Deepwater Horizon oil spill. Total hydrocarbon concentrations in salt marsh sediments were highest in June and July 2010 and decreased in September 2010. Coupled PhyloChip and GeoChip microarray analyses demonstrated that the microbial community structure and function of the extant salt marsh hydrocarbon-degrading microbial populations changed significantly during the study. The relative richness and abundance of phyla containing previously described hydrocarbon-degrading bacteria (Proteobacteria, Bacteroidetes, and Actinobacteria) increased in hydrocarbon-contaminated sediments and then decreased once hydrocarbons were below detection. Firmicutes, however, continued to increase in relative richness and abundance after hydrocarbon concentrations were below detection. Functional genes involved in hydrocarbon degradation were enriched in hydrocarbon-contaminated sediments then declined significantly (p<0.05) once hydrocarbon concentrations decreased. A greater decrease in hydrocarbon concentrations among marsh grass sediments compared to inlet sediments (lacking marsh grass) suggests that the marsh rhizosphere microbial communities could also be contributing to hydrocarbon degradation. The results of this study provide a comprehensive view of microbial community structural and functional dynamics within perturbed salt marsh ecosystems.
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Affiliation(s)
- Melanie J. Beazley
- Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, United States of America
| | - Robert J. Martinez
- Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, United States of America
| | - Suja Rajan
- Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, United States of America
| | - Jessica Powell
- Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, United States of America
| | - Yvette M. Piceno
- Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Lauren M. Tom
- Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Gary L. Andersen
- Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Terry C. Hazen
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Joy D. Van Nostrand
- Institute for Environmental Genomics, University of Oklahoma, Norman, Oklahoma, United States of America
| | - Jizhong Zhou
- Institute for Environmental Genomics, University of Oklahoma, Norman, Oklahoma, United States of America
| | - Behzad Mortazavi
- Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, United States of America
- Dauphin Island Sea Lab, Dauphin Island, Alabama, United States of America
| | - Patricia A. Sobecky
- Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, United States of America
- * E-mail:
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85
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Cao Z, Liu X, Zhang X, Chen L, Liu S, Hu Y. Short-term effects of diesel fuel on rhizosphere microbial community structure of native plants in Yangtze estuarine wetland. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2012; 19:2179-2185. [PMID: 22227809 DOI: 10.1007/s11356-011-0720-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2011] [Accepted: 12/22/2011] [Indexed: 05/31/2023]
Abstract
PURPOSE In this work, short-term effects of diesel fuel on Huangpu-Yangtze estuarine wetland soil microbial community structure were studied under simulated conditions through phospholipid fatty acids (PLFAs) analysis. Four native plant species, bulrush (Scirpus tripueter), galingale (Cyperus rotundus), wildrice (Zizania latifolia), and reed (Phragmites australis) were tested in the experiments. METHOD In the pot experiment, 20 g rhizosphere soils were mixed with 20 g diesel-blended soils. The concentration of total petroleum hydrocarbon was 16,000 mg/kg. All pots were incubated for 14 days in dark at 28°C and watered with 12 mL sterile distilled water to keep a liquid level. Microbial activity of the samples was assessed by hydrolysis of fluorescein diacetate. Measurements of soil PLFAs and analysis on gas chromatography were performed. RESULTS The microbial activity in the samples of reed was highest after the exposure. In all samples, the common PLFA was straight-chain saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA). After the exposure the relative abundance of MUFA and polyunsaturated fatty acid decreased by 20%, and the relative abundance of straight-chain SFA increased by 20%. The results of diversity and PCA indicated that the effect of diesel pollutant on the microbial community was far stronger than the root effect and the reed roots enhanced the tolerance of soil microorganisms to diesel significantly. CONCLUSIONS All results showed that the soil microbial community structure differed significantly with the exposure to diesel. In reed rhizosphere, the soil microorganisms exhibited a strong resistance to diesel fuel. It confirmed that the root of reed improved the biodegradation ability of soil microorganisms for diesel pollutants and they could be reasonably matched to cure and restore the ecological environment of oil-contaminated wetlands.
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Affiliation(s)
- Zhengnan Cao
- Laboratory of Environmental Remediation, College of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China
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86
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Harkey A, Kim HJ, Kandagatla S, Raner GM. Defluorination of 4-fluorophenol by cytochrome P450(BM₃)-F87G: activation by long chain fatty aldehydes. Biotechnol Lett 2012; 34:1725-31. [PMID: 22639088 DOI: 10.1007/s10529-012-0957-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Accepted: 05/09/2012] [Indexed: 11/25/2022]
Abstract
Cytochrome P450(BM3)-F87G catalyzed the oxidative defluorination of 4-fluorophenol, followed by reduction of the resulting benzoquinone to hydroquinone via the NADPH P450-reductase activity of the enzyme. The k (cat) and K (m) for this reaction were 71 ± 5 min(-1) and 9.5 ± 1.3 mM, respectively. Co-incubation of the reaction mixture with long chain aldehydes stimulated the defluorination reaction, with the 2,3-unsaturated aldehyde, 2-decenal producing a 12-fold increase in catalytic efficiency. At 150 μM aldehyde, k (cat) increased to 158 ± 4, while K (m) decreased to 1.8 ± 0.2. The effects of catalase, glutathione and ascorbate on the reaction were all consistent with a direct oxygen insertion mechanism, as opposed to a radical mechanism. The study demonstrates the potential use of P450(BM3) mutants in oxidative defluorination reactions, and characterizes the novel stimulatory action of straight chain aldehydes on this activity.
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Affiliation(s)
- Alexandria Harkey
- The Department of Chemistry, The University of North Carolina at Greensboro, 416 Sullivan Science Building, Greensboro, NC 27402, USA
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87
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Macci C, Doni S, Peruzzi E, Ceccanti B, Masciandaro G. Bioremediation of polluted soil through the combined application of plants, earthworms and organic matter. ACTA ACUST UNITED AC 2012; 14:2710-7. [DOI: 10.1039/c2em30440f] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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88
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Shimazu S, Ohta M, Ohkawa H, Ashida H. Assays of polychlorinated biphenyl congeners and co-contaminated heavy metals in the transgenic Arabidopsis plants carrying the recombinant guinea pig aryl hydrocarbon receptor-mediated β-glucuronidase reporter gene expression system. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2012; 47:925-932. [PMID: 22938576 DOI: 10.1080/03601234.2012.706549] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The transgenic Arabidopsis plant XgD2V11-6 carrying the recombinant guinea pig (g) aryl hydrocarbon receptor (AhR)-mediated β-glucuronidase (GUS) reporter gene expression system was examined for assay of polychlorinated biphenyl (PCB) congeners and co-contaminated heavy metals. When the transgenic Arabidopsis plants were treated with PCB126 (toxic equivalency factor; TEF: 0.1) and PCB169 (TEF: 0.03), the GUS activity of the whole plants was increased significantly. After treatment with PCB80 (TEF: 0), the GUS activity was nearly the same level as that treated with 0.1% dimethylsulfoxide (DMSO) as a vehicle control. After exposure to a 1:1 mixture of PCB126 and PCB169, the GUS activity was increased additively. However, after exposure to a mixture of PCB126 and PCB80, the GUS activity was lower than that of the treatment with PCB126 alone. Thus, PCB80 seemed to be an antagonist towards AhR. When the transgenic plants were treated with each of the heavy metals Fe, Cu, Zn, Cd and Pb together with PCB126, Cd and Pb increased the PCB126-induced GUS activity. On the other hand, Fe, Cu and Zn did not affect the PCB126-induced GUS activity. In the presence of the biosurfactant mannosylerythritol lipid-B (MEL-B) and the carrier protein bovine serum albumin (BSA), the PCB126-induced GUS activity was increased, but the Cd-assisted PCB126-induced GUS activity was not affected. Thus, MEL-B and BSA seemed to increase uptake and transport of PCB126, respectively.
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Affiliation(s)
- Sayuri Shimazu
- Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
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89
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Thomas JC, Dabkowski RT. Glucose and plant exudate enhanced enumeration of bacteria capable of degrading polycyclic aromatic hydrocarbons. Can J Microbiol 2011; 57:1067-72. [DOI: 10.1139/w11-097] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Enumerating environmental microbial isolates capable of polycyclic aromatic hydrocarbon (PAH) degradation can provide insight into the microbe–plant interactions that facilitate PAH removal. We examined a known PAH degrader ( Pseudomonas putida G7), a nondegrader ( Agrobacterium tumefaciens LBA4404), and several microorganisms isolated from the environment by using a PAH cocktail in an enumeration medium with or without 0.025% (m/v) glucose and (or) root exudates. Compared with the standard most probable number (MPN), the addition of glucose and root exudates in a modified MPN method resulted in a 3- to 11-fold enhancement of PAH degraders being enumerated among microorganisms found in PAH-contaminated soils. High-performance liquid chromatography analysis verified that PAH levels were reduced using this modified enumeration method. Low levels of glucose, perhaps in concert with other materials in exudates, may promote microbial metabolism, thereby enhancing PAH degradation.
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Affiliation(s)
- John C. Thomas
- University of Michigan-Dearborn Department of Natural Sciences, 4901 Evergreen Road, Dearborn, MI 48128-1491, USA
| | - Robert T. Dabkowski
- University of Michigan-Dearborn Department of Natural Sciences, 4901 Evergreen Road, Dearborn, MI 48128-1491, USA
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90
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Técher D, Laval-Gilly P, Henry S, Bennasroune A, Formanek P, Martinez-Chois C, D'Innocenzo M, Muanda F, Dicko A, Rejšek K, Falla J. Contribution of Miscanthus x giganteus root exudates to the biostimulation of PAH degradation: an in vitro study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2011; 409:4489-4495. [PMID: 21782215 DOI: 10.1016/j.scitotenv.2011.06.049] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 06/12/2011] [Accepted: 06/19/2011] [Indexed: 05/31/2023]
Abstract
Phytoremediation is considered as a promising and cost-effective method to enhance bioremediation of polluted soils. Exudation of plant root secondary metabolites similar to organic pollutants may induce the expression of microbial degradative enzymes and favour cometabolism of xenobiotics. We investigated the contribution of Miscanthus x giganteus root exudates in the biostimulation of PAH-degradation. This perennial grass was chosen because of its capability to grow on polluted soils and its high biomass production for non-food purposes. First, the impact of cometabolism phenomena was evaluated on the selective enrichment of pyrene-degrading bacterial consortia. The identification of each isolated strains following incubation with pyrene only, "pyrene+phenanthrene", "pyrene+salycilate" or "pyrene+diesel fuel" showed a varying bacterial diversity and pyrene-degrading ability, depending on the co-substrate used. Then, a microplate assay was designed, based on the simultaneous measurement of bacterial consortia growth and degradation activity, in the presence of PAH and total root exudates. Results showed that i) the addition of root exudates was efficient for promoting bacterial growth, ii) but a selective enrichment of PAH-degraders compared to aliphatic ones could be clearly demonstrated, thereby conducing to an enhanced PAH catabolism. The identification of plant secondary metabolites showed the presence of a broad range of flavonoid-derived compounds that could play a role in cometabolic processes. Microplate assays with the two major molecules, quercetin and rutin, suggested a partial involvement of these compounds in biostimulation processes. Further investigations with the other identified secondary metabolites (apigenin, isovitexin, catechin, gallic and caffeic acid) should provide more information on the exudate-PAH cometabolic degradation phenomenon.
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Affiliation(s)
- Didier Técher
- Laboratoire des Interactions Ecotoxicologie, Biodiversité, Ecosystèmes, Université Paul Verlaine Metz, CNRS UMR7146, IUT Thionville-Yutz, Impasse Alfred Kastler, 57970 Yutz, France.
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91
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Wu FY, Yu XZ, Wu SC, Lin XG, Wong MH. Phenanthrene and pyrene uptake by arbuscular mycorrhizal maize and their dissipation in soil. JOURNAL OF HAZARDOUS MATERIALS 2011; 187:341-347. [PMID: 21282002 DOI: 10.1016/j.jhazmat.2011.01.024] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Revised: 11/22/2010] [Accepted: 01/09/2011] [Indexed: 05/30/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) commonly found in soils can be degraded in rhizosphere, but may also be taken up by plants. The effects of arbuscular mycorrhizal (AM) fungi on uptake of phenanthrene (PHE) and pyrene (PYR) in maize and on their dissipation in soil were investigated using the three-compartmentalized rhizoboxes. Inoculation of Glomus mosseae significantly (p<0.01) increased PHE and PYR concentrations in maize roots and significantly (p<0.05) enhanced PYR translocation from roots to stems in the soil treatments of the PHE+PYR spiked-soils added into the central compartment of the rhizoboxes. There was a significant (p<0.05) dissipation gradient of PHE and PYR observed away from the maize roots, with the highest dissipation rates recorded in rhizosphere zone in the central compartments of the rhizoboxes, followed by near rhizosphere zone and bulk soil zone in the outer compartments. However, G. mosseae only exerted minimal impacts on dissipation of PHE and PYR in the rhizosphere. The present study suggested that the hyphae and extraradical mycelium of AM fungi could play important roles in the uptake and translocation of PHE and PYR in plants. The present results indicated that there is a potential for the use of AM fungi and plant for remediating PAHs contaminated soils.
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Affiliation(s)
- F Y Wu
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
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92
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Tao S, Li L, Ding J, Zhong J, Zhang D, Lu Y, Yang Y, Wang X, Li X, Cao J, Lu X, Liu W. Mobilization of soil-bound residue of organochlorine pesticides and polycyclic aromatic hydrocarbons in an in vitro gastrointestinal model. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:1127-32. [PMID: 21175124 PMCID: PMC3031735 DOI: 10.1021/es1025849] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
A previous study on mobilization of organochlorine pesticides (OCPs) in contaminated soils from the field revealed that the total amount of OCPs measured in digestive fluid and chyme of an in vitro gastrointestinal model was higher than the quantity directly extracted using a solvent extraction without digestion, providing a clue that the bound residue of OCPs might be mobilized. This hypothesis was tested in this study for both OCPs and polycyclic aromatic hydrocarbons (PAHs). Three contaminated surface soil samples with different organic carbon (OC) contents were collected from the field, and extracted with a solvent with and without digestion in an in vitro gastrointestinal model. It was found that bound residues of OCPs and PAHs were mobilized to a certain extent during digestion. The ratios of the mobilized bound residues over the total quantities extracted after digestion (R(b)) varied from 0 to 0.96 for individual compounds. The R(b) was positively correlated with OC content. Among the five constitutes of digestive juice, bile salt was the only one that served to mobilize the bound residues and the extractability of bile salt was constant over a concentration range from 2 to 20 mg/mL. The mobilization process followed typical first-order kinetics. The calculated rate constants suggest that mobilization was fast and 90% of extracted bound residues of OCPs and PAHs were mobilized within 2.4 and 4.8 h, respectively.
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Affiliation(s)
- Shu Tao
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
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93
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Polycyclic Aromatic Hydrocarbons in Water from the Menderes River, Turkey. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2011; 86:221-5. [PMID: 21253698 DOI: 10.1007/s00128-011-0199-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Accepted: 01/11/2011] [Indexed: 12/08/2022]
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94
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Using Plants to Remove Foreign Compounds from Contaminated Water and Soil. PLANT ECOPHYSIOLOGY 2011. [DOI: 10.1007/978-90-481-9852-8_8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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95
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Biswas DK, Scannell G, Akhmetov N, Fitzpatrick D, Jansen MAK. 2,4,6-Trichlorophenol mediated increases in extracellular peroxidase activity in three species of Lemnaceae. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2010; 100:289-294. [PMID: 20810175 DOI: 10.1016/j.aquatox.2010.08.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2010] [Revised: 07/30/2010] [Accepted: 08/05/2010] [Indexed: 05/29/2023]
Abstract
Chlorinated phenols, or chlorophenols, are persistent priority pollutants that are widespread in the environment. Class III peroxidases are well-characterised plant enzymes that can catalyse the oxidative dechlorination of chlorophenols. Expression of these enzymes by plants is commonly associated with plant stress, therefore limiting scope for phytoremediation. In this study, we have quantitatively compared peroxidase activity and phytotoxicity as a function of 2,4,6-trichlorophenol (TCP) concentration in three species of Lemnaceae; Lemna minor, Lemna gibba and Landoltia punctata. Effects of TCP on the growth rates of the three species differed considerably with L. punctata being the most tolerant species. TCP also affected photosynthetic parameters, causing a decrease in open photosystem II reaction centres (qP) and, in L. punctata only, a decrease in non-photochemical quenching (qN). In parallel, TCP exposure resulted in increased peroxidase activity in all three species. Peroxidase activity in L. minor and L. gibba displayed an inverse relationship with biomass accumulation, i.e. the more growth reduction the more peroxidase activity. In contrast, induction of peroxidase activity in L. punctata was bi-phasic, with a TCP-induced activity peak at concentrations that had no major effect on growth, and further induction under phytotoxic concentrations. The mechanism by which L. punctata recognises and responds to low concentrations of an anthropogenic compound, in the absence of wide-ranging stress, remains enigmatic. However, we conclude that this "window" of peroxidase production in the absence of major growth inhibition offers potential for the development of sustainable, peroxidise-mediated phytoremediation systems.
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Affiliation(s)
- Dilip K Biswas
- Department of Zoology, Ecology and Plant Science, University College Cork, Cork, Ireland
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96
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A rice cytochrome P450 OsCYP84A that may interact with the UV tolerance pathway. Biosci Biotechnol Biochem 2010; 74:1045-9. [PMID: 20460707 DOI: 10.1271/bbb.90942] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cytochrome P450s are widespread in the plant kingdom. The functions of plant P450s are dispersed through many aspects of plant metabolisms, which are involved in the biosynthesis of defense compounds and protectants against ultraviolet rays, as well as metabolic pathways for the biosynthesis and/or degradation of fatty acids, hormones, and signaling molecules. We found a gene for rice P450, OsCYP84A, which was classified into CYP84A in the CYP71 clan. Reverse transcription-polymerase chain reaction (RT-PCR) analysis indicated that this gene was ubiquitously expressed without any temporal and spatial specificity under normal growth conditions, but its expression was inducibly and significantly increased by ultraviolet (UV)-B and UV-C irradiation. Rice transformants in which OsCYP84A expression was suppressed by the antisense gene showed apparent growth retardation with obvious symptoms of damage on the plant bodies under UV-B irradiation, although no phenotypic alteration occurred under normal growth conditions. These results suggest the existence of a novel UV-tolerance system involving OsCYP84A.
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Weisman D, Alkio M, Colón-Carmona A. Transcriptional responses to polycyclic aromatic hydrocarbon-induced stress in Arabidopsis thaliana reveal the involvement of hormone and defense signaling pathways. BMC PLANT BIOLOGY 2010; 10:59. [PMID: 20377843 PMCID: PMC2923533 DOI: 10.1186/1471-2229-10-59] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Accepted: 04/07/2010] [Indexed: 05/18/2023]
Abstract
BACKGROUND Polycyclic aromatic hydrocarbons (PAHs) are toxic, widely-distributed, environmentally persistent, and carcinogenic byproducts of carbon-based fuel combustion. Previously, plant studies have shown that PAHs induce oxidative stress, reduce growth, and cause leaf deformation as well as tissue necrosis. To understand the transcriptional changes that occur during these processes, we performed microarray experiments on Arabidopsis thaliana L. under phenanthrene treatment, and compared the results to published Arabidopsis microarray data representing a variety of stress and hormone treatments. In addition, to probe hormonal aspects of PAH stress, we assayed transgenic ethylene-inducible reporter plants as well as ethylene pathway mutants under phenanthrene treatment. RESULTS Microarray results revealed numerous perturbations in signaling and metabolic pathways that regulate reactive oxygen species (ROS) and responses related to pathogen defense. A number of glutathione S-transferases that may tag xenobiotics for transport to the vacuole were upregulated. Comparative microarray analyses indicated that the phenanthrene response was closely related to other ROS conditions, including pathogen defense conditions. The ethylene-inducible transgenic reporters were activated by phenanthrene. Mutant experiments showed that PAH inhibits growth through an ethylene-independent pathway, as PAH-treated ethylene-insensitive etr1-4 mutants exhibited a greater growth reduction than WT. Further, phenanthrene-treated, constitutive ethylene signaling mutants had longer roots than the untreated control plants, indicating that the PAH inhibits parts of the ethylene signaling pathway. CONCLUSIONS This study identified major physiological systems that participate in the PAH-induced stress response in Arabidopsis. At the transcriptional level, the results identify specific gene targets that will be valuable in finding lead compounds and engineering increased tolerance. Collectively, the results open a number of new avenues for researching and improving plant resilience and PAH phytoremediation.
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Affiliation(s)
- David Weisman
- Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd, Boston, MA 02125, USA
| | - Merianne Alkio
- Institute of Biological Production Systems, Fruit Science Section, Leibniz University Hannover, Herrenhäuser Str 2, D-30419 Hannover, Germany
| | - Adán Colón-Carmona
- Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd, Boston, MA 02125, USA
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98
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Ma B, He Y, Chen HH, Xu JM, Rengel Z. Dissipation of polycyclic aromatic hydrocarbons (PAHs) in the rhizosphere: synthesis through meta-analysis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2010; 158:855-861. [PMID: 19854547 DOI: 10.1016/j.envpol.2009.09.024] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2009] [Revised: 09/20/2009] [Accepted: 09/23/2009] [Indexed: 05/28/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are widespread and persistent organic pollutants with high carcinogenic effect and toxicity; their behavior and fate in the soil-plant system have been widely investigated. In the present paper, meta-analysis was used to explore the interaction between plant growth and dissipation of PAHs in soil based on the large body of published literature. Plants have a promoting effect on PAH dissipation in soils. There was no difference in PAH dissipation between soils contaminated with single and mixed PAHs. However, plants had a more obvious effect on PAH dissipation in freshly-spiked soils than in long-term field-polluted soils. Additionally, a positive effect of the number of microbial populations capable of degrading PAHs was observed in the rhizosphere compared with the bulk soil. Our meta-analysis established the importance of the rhizosphere effect on PAH dissipation in variety of the soil-plant systems.
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Affiliation(s)
- Bin Ma
- Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, College of Environmental and Natural Resource Sciences, Zhejiang University, Hangzhou 310029, China
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99
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Mujahid M, Sasikala C, Ramana CV. Aniline-induced tryptophan production and identification of indole derivatives from three purple bacteria. Curr Microbiol 2010; 61:285-90. [PMID: 20852980 DOI: 10.1007/s00284-010-9609-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Accepted: 02/04/2010] [Indexed: 11/28/2022]
Abstract
Growth on aniline by three purple non-sulfur bacteria (Rhodospirillum rubrum ATCC 11170, Rhodobacter sphaeroides DSM 158, and Rubrivivax benzoatiliticus JA2) as nitrogen, or carbon source could not be demonstrated. However in its presence, production of indole derivatives was observed with all the strains tested. At least 14 chromatographically (HPLC) distinct peaks were observed at the absorption maxima of 275-280 nm from aniline induced cultures. Five major indoles were identified based on HPLC and LC-MS/MS analysis. While tryptophan was the major common metabolite for all the three aniline induced cultures, production of indole-3-acetic acid was observed with Rvi. benzoatilyticus JA2 alone, while indole-3-aldehyde was identified from Rvi. benzoatilyticus JA2 and Rba. sphaeroides DSM 158. Indole-3-ethanol was identified only from Rsp. rubrum ATCC 1170 and anthranilic acid was identified from Rba. sphaeroides DSM 158.
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Affiliation(s)
- Md Mujahid
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad 500 046, India
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100
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Korade DL, Fulekar MH. Rhizosphere remediation of chlorpyrifos in mycorrhizospheric soil using ryegrass. JOURNAL OF HAZARDOUS MATERIALS 2009; 172:1344-1350. [PMID: 19720454 DOI: 10.1016/j.jhazmat.2009.08.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2009] [Revised: 07/10/2009] [Accepted: 08/02/2009] [Indexed: 05/28/2023]
Abstract
The potential of ryegrass for rhizosphere bioremediation of chlorpyrifos in mycorrhizal soil was investigated by the green house pot culture experiments. The pot cultured soil amended at initial chlorpyrifos concentration of 10mg/kg was observed to be degraded completely within 7 days where the rest amended concentrations (25-100mg/kg) decreased rapidly under the influence of ryegrass mycorrhizosphere as the incubation progressed till 28 days. This bioremediation of chlorpyrifos in soil is attributed to the microorganisms associated with the roots in the ryegrass rhizosphere, therefore the microorganisms surviving in the rhizospheric soil spiked at highest concentration (100mg/kg) was assessed and used for isolation of chlorpyrifos degrading microorganisms. The potential degrader identified by 16s rDNA analysis using BLAST technique was Pseudomonas nitroreducens PS-2. Further, bioaugmentation for the enhanced chlorpyrifos biodegradation was performed using PS-2 as an inoculum in the experimental set up similar to the earlier. The heterotrophic bacteria and fungi were also enumerated from the inoculated and non-inoculated rhizospheric soils. In bioaugmentation experiments, the percentage dissipation of chlorpyrifos was 100% in the inoculated rhizospheric soil as compared to 76.24, 90.36 and 90.80% in the non-inoculated soil for initial concentrations of 25, 50 and 100mg/kg at the 14th, 21st and 28th day intervals respectively.
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Affiliation(s)
- Deepali L Korade
- Environmental Biotechnology Laboratory, Department of Life Sciences, University of Mumbai, Vidyanagari Campus, Santacruz (E), Mumbai 400098, India
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