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Chakravarty P, Deka H, Chowdhury D. Green titanium dioxide (TiO 2) nanoparticles assisted biodegradation of anthracene employing Serratia quinivorans HP5. J Basic Microbiol 2024; 64:e2300680. [PMID: 38381060 DOI: 10.1002/jobm.202300680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 12/28/2023] [Accepted: 02/03/2024] [Indexed: 02/22/2024]
Abstract
The anthracene biodegradation potential of Serratia quinivorans HP5 was studied under a controlled laboratory environment. The green TiO2 nanoparticles (NPs) synthesized from Paenibacillus sp. HD1PAH was used to accelerate the biodegradation process. The synergistic application of TiO2 NPs and S. quinivorans HP5 resulted in a reduction of anthracene concentration by 1.2 folds in liquid-medium and 1.5 folds in contaminated soil. Gas-chromatography and mass-spectrometric investigation showed the production of four anthracene derivatives, namely 1,2-anthracene dihydrodiol, 6,7-benzocoumarin, anthrone, and 9,10-anthraquinoneat the termination of experimental periods. Furthermore, bacterial biomass increased by 23.3 folds in the presence of TiO2 NPs, and overall soil enzyme activities were enhanced by 4.2 folds in the treated samples. In addition, there was a negative correlation observed between the biomass of S. quinivorans HP5 and the concentrations of anthracene, suggesting the involvement of bacterium in anthracene biodegradation processes. The degradation pathway of anthracene revealed its transformation into the less toxic compound 9,10-anthraquinone. Overall, this study elucidates a novel biodegradation pathway for anthracene and highlights the potential of nano-assisted bacterial remediation as a promising approach for environmental cleanup.
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Affiliation(s)
- Paramita Chakravarty
- Ecology and Environmental Remediation Laboratory, Department of Botany, Gauhati University, Guwahati, Assam, India
| | - Hemen Deka
- Ecology and Environmental Remediation Laboratory, Department of Botany, Gauhati University, Guwahati, Assam, India
| | - Devasish Chowdhury
- Material Nanochemistry Laboratory, Physical Sciences Division, Institute of Advanced Study in Science and Technology, Paschim Boragaon, Guwahati, Assam, India
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Jiménez-Volkerink SN, Jordán M, Smidt H, Minguillón C, Vila J, Grifoll M. Metagenomic insights into the microbial cooperative networks of a benz(a)anthracene-7,12-dione degrading community from a creosote-contaminated soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:167832. [PMID: 37863223 DOI: 10.1016/j.scitotenv.2023.167832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/11/2023] [Accepted: 10/12/2023] [Indexed: 10/22/2023]
Abstract
Genotoxicity of PAH-contaminated soils can eventually increase after bioremediation due to the formation and accumulation of polar transformation products, mainly oxygenated PAHs (oxy-PAHs). Biodegradation of oxy-PAHs has been described in soils, but information on the microorganisms and mechanisms involved is still scarce. Benz(a)anthracene-7,12-dione (BaAQ), a transformation product from benz(a)anthracene frequently detected in soils, presents higher genotoxic potential than its parent PAH. Here, using sand-in-liquid microcosms we identified a specialized BaAQ-degrading subpopulation in a PAH-contaminated soil. A BaAQ-degrading microbial consortium was obtained by enrichment in sand-in-liquid cultures with BaAQ as sole carbon source, and its metagenomic analysis identified members of Sphingobium, Stenotrophomonas, Pusillimonas, Olivibacter, Pseudomonas, Achromobacter, and Hyphomicrobiales as major components. The integration of data from metabolomic and metagenomic functional gene analyses of the consortium revealed that the BaAQ metabolic pathway was initiated by Baeyer-Villiger monooxygenases (BVMOs). The presence of plasmid pANTQ-1 in the metagenomic sequences, identified in a previous multi-omic characterization of a 9,10-anthraquinone-degrading isolate recovered from the same soil, suggested the occurrence of a horizontal gene transfer event. Further metagenomic analysis of the BaAQ-degrading consortium also provided insights into the potential roles and interactions within the consortium members. Several potential auxotrophies were detected, indicating that relevant nutritional interdependencies and syntrophic associations were taking place within the community members, not only to provide suitable carbon and energy sources, but also to supply essential nutrients and cofactors. Our work confirms the essential role that BVMO may play as a detoxification mechanism to mitigate the risk posed by oxy-PAH formation during bioremediation of contaminated soils.
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Affiliation(s)
- Sara N Jiménez-Volkerink
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Av. Diagonal, 643, 08028 Barcelona, Spain
| | - Maria Jordán
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Av. Diagonal, 643, 08028 Barcelona, Spain
| | - Hauke Smidt
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708, WE, Wageningen, the Netherlands
| | - Cristina Minguillón
- Department of Nutrition, Food Science and Gastronomy, University of Barcelona, Avda. Prat de la Riba, 171, 08921 Sta. Coloma de Gramanet, Barcelona, Spain
| | - Joaquim Vila
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Av. Diagonal, 643, 08028 Barcelona, Spain.
| | - Magdalena Grifoll
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Av. Diagonal, 643, 08028 Barcelona, Spain
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Jan S, Mishra AK, Bhat MA, Bhat MA, Jan AT. Pollutants in aquatic system: a frontier perspective of emerging threat and strategies to solve the crisis for safe drinking water. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:113242-113279. [PMID: 37864686 DOI: 10.1007/s11356-023-30302-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 10/03/2023] [Indexed: 10/23/2023]
Abstract
Water is an indispensable natural resource and is the most vital substance for the existence of life on earth. However, due to anthropogenic activities, it is being polluted at an alarming rate which has led to serious concern about water shortage across the world. Moreover, toxic contaminants released into water bodies from various industrial and domestic activities negatively affect aquatic and terrestrial organisms and cause serious diseases such as cancer, renal problems, gastroenteritis, diarrhea, and nausea in humans. Therefore, water treatments that can eliminate toxins are very crucial. Unfortunately, pollution treatment remains a difficulty when four broad considerations are taken into account: effectiveness, reusability, environmental friendliness, and affordability. In this situation, protecting water from contamination or creating affordable remedial techniques has become a serious issue. Although traditional wastewater treatment technologies have existed since antiquity, they are both expensive and inefficient. Nowadays, advanced sustainable technical approaches are being created to replace traditional wastewater treatment processes. The present study reviews the sources, toxicity, and possible remediation techniques of the water contaminants.
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Affiliation(s)
- Saima Jan
- School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, 185234, J&K, India
| | | | - Mujtaba Aamir Bhat
- School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, 185234, J&K, India
| | - Mudasir Ahmad Bhat
- School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, 185234, J&K, India
| | - Arif Tasleem Jan
- School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, 185234, J&K, India.
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Chakravarty P, Deka H, Chowdhury D. Anthracene removal potential of green synthesized titanium dioxide nanoparticles (TiO 2-NPs) and Alcaligenes faecalis HP8 from contaminated soil. CHEMOSPHERE 2023; 321:138102. [PMID: 36764617 DOI: 10.1016/j.chemosphere.2023.138102] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 02/07/2023] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
Anthracene biodegradation potential has been studied in liquid culture and soil microcosm environment by employing green synthesized TiO2 nanoparticles (NPs) and Alcaligenes faecalis HP8. The bacterium was isolated from crude oil contaminated soil, while TiO2 nanoparticles were synthesized using Paenibacillus sp. HD1PAH and Cyperus brevifolius which have PAHs remediation abilities. The dual application of TiO2 nanoparticles and Alcaligenes faecalis HP8 decreases anthracene concentration up to 21.3% in liquid at the end of 7 days and 37.9% in the soil treatments after completion of 30 days. Besides, the GC-MS analysis revealed production of five metabolites including 1,2-anthracenedihydrodiol; 6,7-benzocoumarin; 3-hydroxy-2-naphthoic acid; salicylic acid and 9,10-anthraquinone at different time interval of the treatments. Anthracene degradation pathway confirms the breakdown of three ring anthracene to one ring salicylic acid. Additionally, soil dehydrogenase, urease, alkaline phosphatase, catalase and amylase activities increased up to 4.09 folds, 8.6 folds, 4.4 folds, 3.6 folds and 2.1 folds respectively after the combined treatments of TiO2 nanoparticles and Alcaligenes faecalis HP8. The bacterial biomass and residual anthracene concentration were found to be negatively correlated. Finally, the study brings into light a novel anthracene biodegradation pathway and provides a new dimension in nano assisted bacterial remediation.
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Affiliation(s)
- Paramita Chakravarty
- Ecology and Environmental Remediation Laboratory, Department of Botany, Gauhati University, Guwahati, 781014, Assam, India
| | - Hemen Deka
- Ecology and Environmental Remediation Laboratory, Department of Botany, Gauhati University, Guwahati, 781014, Assam, India.
| | - Devasish Chowdhury
- Material Nanochemistry Laboratory, Physical Sciences Division, Institute of Advanced Study in Science and Technology, Paschim Boragaon, Garchuk, Guwahati, 781035, India
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Zhao Z, Oury BM, Xia L, Qin Z, Pan X, Qian J, Luo F, Wu Y, Liu L, Wang W. The ecological response and distribution characteristics of microorganisms and polycyclic aromatic hydrocarbons in a retired coal gas plant post-thermal remediation site. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159314. [PMID: 36220477 DOI: 10.1016/j.scitotenv.2022.159314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 09/16/2022] [Accepted: 10/05/2022] [Indexed: 06/16/2023]
Abstract
Thermal remediation is one of the most common approaches of removing organic pollutants in the retired contamination sites. However, little is known about the performance of bacterial community characteristics after in situ thermal remediation. In this study, the ecological response and spatial distributional characteristics of microorganisms and polycyclic aromatic hydrocarbons (PAHs) were investigated using a high throughput sequencing method in a retired coal gas plant site after in situ thermal remediation in Nanjing, China. Combination of Venn, clustering-correlation heatmap and two - factor correlation network analysis revealed that, microbial communities were obviously affected and classified by soil depths, temperature, and contamination level, respectively. The common and endemic microorganisms of each group were identified. The relative abundances of Thermaerobacter, Calditerricola, Brevibacillus, Ralstonia and Rhodococcus (aerobic bacteria) gradually declined with the increase of soil depth, while those of Bacillus, Fictibacillus, Paenibacillus, Rheinheimera presented opposite tendency. Some thermophilic degradation bacteria of PAHs, including Thermaerobacter, Calditerricola, Bacillus, Rhodococcus, unclassified_p__Firmicutes, Arthrobacter and Deinococcus, were identified and increased in the abundance at heavily polluted sites. Additionally, Proteobacteria, Bacteroidota, Deinococcota, Chloroflexi, Acidobacteriota, and Actinobacteriota showed negative response to the increase of soil depth, temperature and pollution level, while Firmicutes presented a positive response. This implied that Firmicutes has better stress resistance and adaptability to thermal remediation condition. The key environmental factors affecting microorganism composition and distribution were Temperature, Total nitrogen, Oxidation-Reduction Potential, Organic matters, and PAHs concentrations, which explains the dominant driving mechanism of soil depth, temperature, and contamination level on microbial characteristics in thermal remediation site. Our study could contribute to a better understanding of the resilience and adaptation mechanisms of microbial community at the contaminated site after the in situ thermal remediation.
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Affiliation(s)
- Zhenhua Zhao
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI 48824, USA.
| | - Barry Mody Oury
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Liling Xia
- Nanjing Vocational University of Industry Technology, Nanjing 210016, China.
| | - Zhirui Qin
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Xiangyu Pan
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Jichan Qian
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Fangzhou Luo
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Yong Wu
- Nanjing Qingzhan Environmental Engineering CO. Ltd, China
| | - Luqi Liu
- SUMEC Complete Equipment & Engineering CO. LTD, Nanjing 210018, China
| | - Wei Wang
- SUMEC Complete Equipment & Engineering CO. LTD, Nanjing 210018, China
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Dayana Priyadharshini S, Suresh Babu P, Manikandan S, Subbaiya R, Govarthanan M, Karmegam N. Phycoremediation of wastewater for pollutant removal: A green approach to environmental protection and long-term remediation. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 290:117989. [PMID: 34433126 DOI: 10.1016/j.envpol.2021.117989] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 08/03/2021] [Accepted: 08/14/2021] [Indexed: 06/13/2023]
Abstract
Surface and water bodies in many parts of the world are affected due to eutrophication, contamination and depletion. The approach of wastewater treatment using algae for eliminating nutrients and other pollutants from domestic wastewater is growing interest among the researchers. However, sustainable treatment of the wastewater is considered to be important in establishing more effective nutrient and pollutant reduction using algal systems. In comparison to the conventional method of remediation, there are opportunities to commercially viable businesses interest with phycoremediation, thus by achieving cost reductions and renewable bioenergy options. Phycoremediation is an intriguing stage for treating wastewater since it provides tertiary bio-treatment while producing potentially valuable biomass that may be used for a variety of applications. Furthermore, the phycoremediation provides the ability to remove heavy metals as well as harmful organic substances, without producing secondary contamination. In this review, the role of microalgae in treating different wastewaters and the process parameters affecting the treatment and future scope of research have been discussed. Though several algae are employed for wastewater treatment, species of the genera Chlamydomonas, Chlorella, and Scenedesmus are extensively utilized. Interestingly, there is a vast scope for employing algal species with high flocculation capacity and adsorption mechanisms for the elimination of microplastics. In addition, the algal biomass generated during phycoremediation has been found to possess high protein and lipid contents, promising their exploitation in biofuel, food and animal feed industries.
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Affiliation(s)
| | - Palanisamy Suresh Babu
- Department of Biotechnology, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha Nagar, Thandalam, Chennai, 602 105, Tamil Nadu, India; Faculty of Pharmaceutical Sciences, UCSI University, 56000, Cheras, Kuala Lumpur, Malaysia
| | - Sivasubramanian Manikandan
- Department of Biotechnology, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha Nagar, Thandalam, Chennai, 602 105, Tamil Nadu, India
| | - Ramasamy Subbaiya
- Department of Biological Sciences, School of Mathematics and Natural Sciences, The Copperbelt University, Riverside, Jambo Drive, P O Box 21692, Kitwe, Zambia
| | - Muthusamy Govarthanan
- Department of Environmental Engineering, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Natchimuthu Karmegam
- Department of Botany, Government Arts College (Autonomous), Salem, 636 007, Tamil Nadu, India.
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Sompark C, Singkhonrat J, Sakkayawong N. Biotransformation of Reactive Red 141 by Paenibacillus terrigena KKW2-005 and Examination of Product Toxicity. J Microbiol Biotechnol 2021; 31:967-977. [PMID: 34099601 PMCID: PMC9705871 DOI: 10.4014/jmb.2104.04041] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 05/28/2021] [Accepted: 05/31/2021] [Indexed: 12/15/2022]
Abstract
A total of 37 bacterial isolates were obtained from dye-contaminated soil samples at a textile processing factory in Nakhon Ratchasima Province, Thailand, and the potential of the isolates to decolorize and biotransform azo dye Reactive Red 141 (RR141) was investigated. The most potent bacterium was identified as Paenibacillus terrigena KKW2-005, which showed the ability to decolorize 96.45% of RR141 (50 mg/l) within 20 h under static conditions at pH 8.0 and a broad temperature range of 30-40°C. The biotransformation products were analyzed by using UV-Vis spectrophotometry and Fourier-transform infrared spectroscopy. Gas chromatography-mass spectroscopy analysis revealed four metabolites generated from the reductive biodegradation, namely sodium 3-diazenylnaphthalene-1,5-disulfonate (I), sodium naphthalene-2-sufonate (II), 4-chloro-1,3,5-triazin-2-amine (III) and N1-(1,3,5-triazin-2-yl) benzene-1,4-diamine (IV). Decolorization intermediates reduced phytotoxicity as compared with the untreated dye. However, they had phytotoxicity when compared with control, probably due to naphthalene and triazine derivatives. Moreover, genotoxicity testing by high annealing temperature-random amplified polymorphic DNA technique exhibited different DNA polymorphism bands in seedlings exposed to the metabolites. They compared to the bands found in seedlings subjected to the untreated dye or distilled water. The data from this study provide evidence that the biodegradation of Reactive Red 141 by P. terrigena KKW2-005 was genotoxic to the DNA seedlings.
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Affiliation(s)
- Chalermwoot Sompark
- Department of Biotechnology, Faculty of Science and Technology, Thammasat University, Rangsit Centre, Khlong Nueng, Klong Luang, Pathum Thani, Thailand, 12120
| | - Jirada Singkhonrat
- Department of Chemistry, Faculty of Science and Technology, Thammasat University, Rangsit Centre, Khlong Nueng, Klong Luang, Pathum Thani, Thailand, 12120
| | - Niramol Sakkayawong
- Department of Biotechnology, Faculty of Science and Technology, Thammasat University, Rangsit Centre, Khlong Nueng, Klong Luang, Pathum Thani, Thailand, 12120,Corresponding author Phone: +66-2564-4444 ext 2068 Fax: +66-2564-4500 E-mail:
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Borah G, Nath N, Deka H. Effects on anatomy of some abundantly growing herbs in the effluents contaminated soil of oil refinery. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:11549-11557. [PMID: 33128153 DOI: 10.1007/s11356-020-11407-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 10/26/2020] [Indexed: 06/11/2023]
Abstract
The soil contaminations from refinery effluents are still a burning problem in the oil-producing nations of the globe. In the present study, the effect of oil refinery effluents on anatomical characteristics of some selected herbs has been studied. The abundantly growing herb species of the contaminated sites that includes Ageratum conyzoides, Alternanthera paronychioides, and Cyperus brevifolius were selected for the anatomical investigation. The samplings site of these herbs was adjacent to Numaligarh oil refinery, Assam, India, where a huge amount of oil effluents are released every day. For comparison, the same plant species were collected from the control sites where effluent contamination was not evident. The results showed that anatomical sections of both shoots and roots of the studied herbs are adversely affected by oil refinery effluents contamination and showed various structural abnormalities. Dark/blackish depositions were traced in the different tissues that include the epidermis, cortex, vascular bundles and pith region in the plant samples collected from the effluents contaminated areas. The results also revealed widening, thickening, and reduction of different tissues of the studied plants besides affecting overall shoot diameter; cell sizes; and length of epidermis, cortex, vascular bundles, and pith as a defense mechanism against the adverse condition created due to effluent contamination. Such abnormalities were not observed in control plants.
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Affiliation(s)
- Glory Borah
- Environmental Botany and Biotechnology Laboratory, Department of Botany, Gauhati University, Guwahati, Assam, 781014, India
| | - Namita Nath
- Environmental Botany and Biotechnology Laboratory, Department of Botany, Gauhati University, Guwahati, Assam, 781014, India
| | - Hemen Deka
- Environmental Botany and Biotechnology Laboratory, Department of Botany, Gauhati University, Guwahati, Assam, 781014, India.
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Sarma H, Sonowal S, Prasad MNV. Plant-microbiome assisted and biochar-amended remediation of heavy metals and polyaromatic compounds ─ a microcosmic study. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 176:288-299. [PMID: 30947032 DOI: 10.1016/j.ecoenv.2019.03.081] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Revised: 03/13/2019] [Accepted: 03/19/2019] [Indexed: 05/18/2023]
Abstract
The study has been carried out to develop a plant-microbes assisted remediation technology to accelerate polyaromatic hydrocarbons (PAHs) degradation and heavy metals (HMs) removal in a microcosmic experiment. The quaternary mixture of PAHs (phenanthrene, anthracene, pyrene, and benzo[a] pyrene) and metals (Cr, Ni, and Pb) spiked the soil, constructing a microcosm; the microcosms were bioaugmented with newly developed plant bacterial consortia (Cpm1 and Cpm2). The microcosms were amended with biochar (sieved particle size 0.5-2 mm) as redox regulators to reduce oxidative stress of plant-microbe systems. To formulate the two plant-bacterial consortia, plant species were collected and bacteria were isolated from oil spill soil. The bacterial strains used in two formulated consortia includes ─ Cpm1 (Enterobacter cloacae HS32, Brevibacillus reuszeri HS37, and Stenotrophomonas sp. HS16) and Cpm2 (Acinetobacter junii HS29, Enterobacter aerogenes HS39 and Enterobacter asburiae HS22). The PAHs degradation and metal removal efficacy of the consortia (Cpm1 and Cpm2) were studied after 24 weeks of trial. The physicochemical properties of microcosm's soil (M2 and M3) were assessed after experimentation, which resulted in the finding that the soil exhibits dropped in pH from basic to neutral after application of the plant microbe's consortium. The electrical conductivity was lower in M2 and M3 soils, with a range between 1.60 and 1.80 mS/cm after the treatment. The Gas Chromatography/Mass Spectrometry (GC/MS) results illustrate how metabolites with the different molecular weight (M.W) were found in M2 and M3 soils (184─446), as a result of the plant-microbes mediated rhizodegradation of four spiked PAHs. The metals in microcosm's soil are very low in concentration after 24 weeks of trial when compared to control(M1). The Cr, Ni and Pb removal percentages were found in 45.79, 42.19 and 44.85 in M2. However, the removal percentages were found to be 45.41, 41.47 and 44.25 respectively for these same HMs in M3 soil. Both the consortia that were newly developed showed similar trends of metals removal and PAHs degradation. This study provides a breakthrough in the area of rhizosphere engineering with the goal of maintaining a sustainable application of plant-microbes in ecosystem services.
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Affiliation(s)
- Hemen Sarma
- Department of Botany, N N Saikia College, Titabar, 785630, Assam, India.
| | - S Sonowal
- Department of Botany, N N Saikia College, Titabar, 785630, Assam, India
| | - M N V Prasad
- School of Life Sciences, University of Hyderabad, Hyderabad, 500046, Telengana, India
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