Download or read book Taxonomic and Functional Characterization of Microbial Communities Linked to Chlorinated Solvent 1 4 dioxane and Rdx Biodegradation in Groundwater and Soil Microcosms written by Hongyu Dang and published by . This book was released on 2021 with total page 221 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bioremediation is becoming increasing popular for the remediation of sites contaminated with a range of different contaminants. Molecular methods such as 16S rRNA gene amplicon sequencing, shotgun sequencing, and high throughput quantitative PCR offer much potential for examining the microorganisms and functional genes associated with contaminant biodegradation, which can provide critical additional lines of evidence for effective site remediation. In this work, the first project examined the taxonomic and functional biomarkers associated with chlorinated solvent and 1,4-dioxane biodegradation in groundwater from five contaminated sites. Each site had previously been bioaugmented with the commercially available dechlorinating mixed culture, SDC-9. The results highlighted the occurrence of numerous genera previously linked to chlorinated solvent biodegradation. The functional gene analysis indicated two reductive dehalogenase genes (vcrA and tceA) from Dehalococcoides mccartyi were abundant. Additionally, aerobic and anaerobic biomarkers for the biodegradation of various chlorinated compounds were observed across all sites. The approach used (shotgun sequencing) is advantageous over many other methods because an unlimited number of functional genes can be examined and a more complete picture of the functional abilities of microbial communities can be depicted. Another research project evaluated the functional genes and species associated with RDX biodegradation at a RDX contaminated Navy site where biostimulation had been adopted. For this, DNA samples extracted from groundwater samples pre- and post-biostimulation were subject to shotgun sequencing and high throughput qPCR. DNA sequences from thirty-one RDX biodegraders were detected, with the most abundant species being Variovorax sp. JS1663. Further, nine RDX biodegrading species significantly (p

Download or read book Microbial Ecology and Bioremediation of 1 4 Dioxane and Chlorinated Solvents Contaminated Groundwater and Soil written by Yu Miao and published by . This book was released on 2019 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is crucial to consider the impact of abiotic and biological remediation technologies on the microbial ecology to predict the success of short-term active treatments and long-term passive attenuation processes. In this research, three bioremediation strategies were tested individually or coupled with chemical remedies in bench- and pilot-scale studies for removing 1,4-dioxane and chlorinated volatile organic compounds (CVOCs), which are widespread co-occurring contaminants in soils and water resources across the U.S., attracting attention because of their potential carcinogenicities. In each project, amplification of taxonomic and functional genes by qPCR as well as metagenomics including high-throughput sequencing were applied to provide reliable information about microbial communities in the ecological matrices as they transitioned from 1,4-dioxane and CVOC contaminations to exposures from treatment technologies and degradation products. A comprehensive multiple lines of evidence approach provided evidence of natural attenuation by microorganisms capable of metabolic or co-metabolic degradation of 1,4-dioxane within a large, diffuse plume. A pilot study of bioaugmentation with Pseudonocardia dioxanivorans CB1190 through direct injection as well as in-situ bioreactor was successfully conducted at a site impacted by 1,4-dioxane and CVOCs. Bench-scale microcosms were established to inform pilot-scale ex-situ bioreactors and in-situ propane biosparging at an industrial site. 1,4-Dioxane co-metabolism by indigenous microbes was accelerated by biostimulation with propane and nutrients. Inoculations with CB1190 or propanotroph, Rhodococcus ruber ENV425, were eventually outcompeted by native microbes, but gene allocations for xenobiotics and lipid metabolism were enhanced and accompanied rapid 1,4-dioxane degradation rates. Three synergistic treatment trains: oxidation & catalysis, oxidation & biodegradation, and catalysis & biodegradation, were applied to achieve nearly complete 1,4-dioxane removals even in the presence of inhibitory CVOCs. While oxidant- or nanocatalyst-tolerant microbes were dominant immediately after chemical processes, the microbial community thrived during the biodegradation in a deterministic process over time, presenting higher biodiversity that indicated a more stable community. The post-treatment community carried various functional potentials, such as degradation of CVOCs and aromatic hydrocarbons, as well as nitrogen fixation. These mechanistic and quantitative data will be valuable for developing synergistic treatments that lead to savings in cost, energy, and substrate amendments for the remediation of contaminant mixtures.

Download or read book Biodegradation and Molecular Analysis of 1 4 dioxane and Other Organic Contaminants in Soils Using Metagenomic Tools written by Vidhya Ramalingam and published by . This book was released on 2021 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: Historically, 1,4-dioxane, a potential human carcinogen, was used as a stabilizer in 1,1,1-trichloroethane (1,1,1-TCA) formulations and is now frequently detected at chlorinated solvent contaminated sites. Bioremediation has emerged as an effective strategy to treat 1,4-dioxane. However, the distribution of 1,4-dioxane degrading species across various environmental samples is generally unknown. Additionally, 1,4-dioxane contamination typically occurs in groundwater under highly reducing conditions. There is a significant knowledge gap and a lack of information on the susceptibility of 1,4-dioxane to biodegradation under such reducing conditions. The success of organic contaminant bioremediation is often linked to the abundance of functional genes present in the soil that are associated with the degradation process. Although some information exists on the presence of these genes in contaminated soils, there is limited knowledge on the presence and diversity of these genes in uncontaminated soils. To address all these knowledge gaps, a series of studies were conducted. The first study aims at identifying which 1,4-dioxane degrading functional genes are present in soil communities and which genera may be using 1,4-dioxane and/or metabolites to support growth across different microbial communities. For this, laboratory sample microcosms and abiotic control microcosms (containing media) were inoculated with four uncontaminated soils and sediments from two contaminated sites. The sample microcosms were amended with 1,4-dioxane thrice and live control microcosms were treated in the same manner, except 1,4-dioxane was not added. Biodegradation was observed and whole genome shotgun sequencing was carried out. Although some degraders previously linked to 1,4-dioxane degradation were detected, Nocardioides, Gordonia and Kribbella were found to be potentially novel degraders. The functional genes associated with 1,4-dioxane demonstrated three genes were present at higher relative abundance values, including Rhodococcus sp. RR1 prmA, Rhodococcus jostii RHA1 prmA and Burkholderia cepacia G4 tomA3. The second study is focused on anaerobic biodegradation of 1,4-dioxane. The potential for 1,4-dioxane biodegradation was examined using multiple inocula and electron acceptor amendments. Compound specific isotope analysis (CSIA) was used to further investigate biodegradation in a subset of the microcosms. DNA was extracted from microcosms exhibiting 1,4-dioxane biodegradation for microbial community analysis using 16S rRNA gene amplicon high throughput sequencing. 1,4-dioxane biodegradation was most commonly observed in the nitrate amended and no electron acceptor treatments. However, it is important to note that the degradation was slow (approximately one year). The third study examines a set of genes associated with organic contaminant degradation in four uncontaminated (agricultural) soils. The abundance and diversity of benA, bph, dbfA, dxnA, etnC, etnE, ppaH, npaH, vcrA, xenA, xenB and xplA were investigated using protein sequences from the Functional Gene Pipeline and Repository (FunGene). The phylogenetic trees created indicate many genera may potentially be associated with each gene including Pseudomonas, Rhodococcus, Mycobacterium and Nocardioides. From these, some strains are well studied and are known to be involved in the biodegradation of organic contaminants and others are potentially new genera that may be associated with the biodegradation of the targeted group of contaminants.

Download or read book Functional Genomics of the Bacterial Degradation of the Emerging Water Contaminants written by Christopher Michael Sales and published by . This book was released on 2012 with total page 1024 pages. Available in PDF, EPUB and Kindle. Book excerpt: The emerging water contaminants 1,4-dioxane and N-nitrosodimethylamine (NDMA) are toxic and classified as probable human carcinogens. Both compounds are persistent in the environment and are highly mobile in groundwater plumes due to their hydrophilic nature. The major source of 1,4-dioxane is due to its use as a stabilizer in the chlorinated solvent 1,1,1-trichloroethane. The presence of NDMA as a water contaminant is related to the release of rocket fuels and its formation in the disinfection of water and wastewater. Prior studies have demonstrated that bacteria expressing monooxygenases are capable of degrading 1,4-dioxane and NDMA. While growth on 1,4-dioxane as a sole carbon and energy source has been reported in Pseudonocardia dioxanivorans CB1190 and Pseudonocardia benzenivorans B5, it is also co-metabolically degradable by a variety of monooxygenase-expressing strains. In contrast, NDMA has only been observed to biodegrade co-metabolically after growth on some monooxygenase-inducing substrates. The fastest rates of NDMA degradation occur in Rhodococcus sp. RR1 and Mycobacterium vaccae JOB5 after growth on propane. Pathways have been proposed for 1,4-dioxane biodegradation in P. dioxanivorans and for NDMA biodegradation in propane-induced Rhodococcus sp. RR1 based only on identified intermediates. The overall goal of this dissertation is to gain a better understanding of the genes and biological pathways responsible for degradation of 1,4-dioxane and NDMA. Due to the lack of molecular sequence information for organisms capable of growth on 1,4-dioxane, the genome of P. dioxanivorans strain CB1190 was sequenced in this study. The genome has a total size of 7,440,794 bp and consists of four replicons: a circular chromosome, a circular plasmid pPSED01, an unclosed circular plasmid pPSED02, and a linear plasmid pPSED03. Analysis of this genome sequence revealed the presence of eight multicomponent monooxygenases: a propane monooxygenase, a phenol monooxygenase, a 4-hydroxyphenylacetate monooxygenase, four aromatic (toluene) monooxygenases, and a tetrahydrofuran (THF) monooxygenase. A total of 92 genes identified as putative dioxygenases were identified. Protein-encoding genes involved in transport systems, signal transduction systems, secretion systems, and heavy-metal and antibiotic resistance were identified. The presence of pathways for carbon and nitrogen metabolism was examined. A complete Calvin-Benson-Bassham carbon fixation pathway was found and a number of carboxylases that function in other carbon fixation pathways were identified. Although P. dioxanivorans has been reported to fix nitrogen, no nitrogenase genes were found. The genome sequence of P. dioxanivorans was compared to other sequenced genomes of members in the family Pseudonocardiaceae, including Amycolatopsis mediterranei S699, Amycolatopsis mediterranei U32, Pseudonocardia sp. P1, Pseudonocardia sp. P2, Saccharomonaspora azurea NA-128, Saccharomonospora paurometabolica YIM 9007, Sacharomonospora viridis DSM43017, Saccharopolyspora erythraea NRRL2338, and Saccharopolyspora spinosa NRRL18395. Genome-aided approaches were employed to identify the protein-encoding genes involved in the metabolic degradation of 1,4-dioxane in P. dioxanivorans. These approaches included whole genome expression microarray transcriptomics, quantitative reverse transcriptase PCR (qRT-PCR), enzyme assays, and heterologous expression clones. Genes differentially expressed during growth on 1,4-dioxane, glycolate (a previously identified degradation intermediate), and pyruvate (control) were analyzed to determine genes differentially expressed and involved in the metabolism of 1,4-dioxane. Based on the differentially expressed genes, the 1,4-dioxane degradation pathway was revised and annotated with the enzymes known to catalyze specific transformation steps. Up-regulation of genes were confirmed and quantified by qRT-PCR. Transcriptional analyses, isotopic tracer analyses with 1,4-[U-13C]-dioxane, and glyoxylate carboligase enzymatic activity assays confirmed the role of glyoxylate as a central intermediate in the degradation of 1,4-dioxane. Specifically, transcriptional analyses indicated that the THF monooxygenase, encoded by thmADBC, is up-regulated during growth on 1,4-dioxane and THF. Furthermore, Rhodococcus jostii RHA1 clones heterologously expressing the P. dioxanivorans genes thmADBC demonstrated 1,4-dioxane and THF degradation activity. A surprising result with the THF monooxygenase expressing clones was the accumulation of the intermediate [beta]-hydroxyethoxyacetic acid (HEAA). This result, combined with the non-inhibitory effect of acetylene on HEAA degradation by 1,4-dioxane grown P. dioxanivorans indicates that a monooxygenase is not involved in the transformation of HEAA as previously hypothesized. Transcriptomic microarray analysis of THF- and succinate-grown cells led to the first proposed THF metabolic degradation pathway for P. dioxanivorans. A novel finding of this transcriptomic microarray analysis was the identification of an alcohol dehydrogenase up-regulated during growth on THF that could catalyze the conversion of 2-hydroxytetrahydrofuran to [gamma]-butyrolactone. The genome sequence of Rhodococcus jostii RHA1 was utilized to determine the propane-induced monooxygenase responsible for NDMA degradation. The degradation of NDMA was characterized in R. jostii RHA1 grown on propane and on non-inducing substrates (LB medium, soy broth, and pyruvate). Propane enhanced the removal rate of NDMA by nearly two orders of magnitude compared to constitutive degradation during growth on non-inducing substrate. Transcriptomic microarray and qRT-PCR analyses demonstrated that propane elicits the up-regulation of a propane monooxygenase gene cluster. Genetic knockouts of the prmA gene encoding the large hydroxylase component of the propane monooxygenase were unable to grow on propane and degrade NDMA. These results indicate that the propane monooxygenase is responsible for NDMA degradation by R. jostii and explain the enhanced co-metabolic degradation of NDMA in the presence of propane. With the newly gained knowledge of the role of propane monooxygenase in NDMA degradation, oligonucleotide degenerate primers targeting prmA were designed and were identify and quantify the presence of propane monooxygenase genes in Rhodoccocus sp. RR1 and M. vaccae JOB5. A homolog to prmA was found in Rhodoccocus sp. RR1 but not in M. vaccae JOB5. The prmA gene in Rhodococcus sp. RR1 was up-regulated during growth on propane relative to pyruvate. Characterization of the kinetics of propane-enhanced NDMA degradation showed that Rhodococcus sp. RR1 and M. vaccae possess similar maximum transformation rates (44 ± 5 and 28 ± 3 mg NDMA(mg protein)-1h-1, respectively). However, a comparison of half saturation constants (Ks, n) and NDMA degradation in the presence of propane revealed pronounced differences between the strains. The Ks, n for Rhodococcus sp. RR1 was 36 ± 10 mg NDMA L-1 while the propane concentration needed to inhibit NDMA rates by 50% (Kinh) occurred at 7,700 mg propane L-1 (R2 = 0.9669). In contrast, M. vaccae had a markedly lower affinity for NDMA verses propane with a calculated Ks, n of 2,200 ± 1,000 mg NDMA L-1 and Kinh of 120 mg propane L-1 (R2 = 0.9895). Differences between the propane monooxygenases in Rhodococcus sp. RR1 and the unidentified enzyme(s) in M. vaccae may explain the disparities in NDMA degradation and inhibition kinetics between these strains.

Download or read book Biostimulation and Microbial Community Profiling Reveal Insights on RDX Transformation in Groundwater written by and published by . This book was released on 2016 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a high explosive released to the environment as a result of weapons manufacturing and testing worldwide. At Los Alamos National Laboratory, the Technical Area (TA) 16 260 Outfall discharged high-explosives-bearing water from a high-explosives-machining facility to Cañon de Valle during 1951 through 1996. These discharges served as a primary source of high-explosives and inorganic-element contamination in the area. Data indicate that springs, surface water, alluvial groundwater, and perched-intermediate groundwater contain explosive compounds, including RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine); HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine); and TNT (2,4,6-trinitrotoluene). RDX has been detected in the regional aquifer in several wells, and a corrective measures evaluation is planned to identify remedial alternatives to protect the regional aquifer. Perched-intermediate groundwater at Technical Area 16 is present at depths from 650 ft to 1200 ft bgs. In this study, we examined the microbial diversity in a monitoring well completed in perched-intermediate groundwater contaminated by RDX, and examined the response of the microbial population to biostimulation under varying geochemical conditions. Results show that the groundwater microbiome was dominated by Actinobacteria and Proteobacteria. A total of 1,605 operational taxonomic units (OTUs) in 96 bacterial genera were identified. Rhodococcus was the most abundant genus (30.6%) and a total of 46 OTUs were annotated as Rhodococcus. One OTU comprising 25.2% of total sequences was closely related to a RDX -degrading strain R. erythropolis HS4. A less abundant OTU from the Pseudomonas family closely related to RDX-degrading strain P. putida II-B was also present. Biostimulation significantly enriched Proteobacteria but decreased/eliminated the population of Actinobacteria. Consistent with RDX degradation, the OTU closely related to the RDX-degrading P. putida strain II-B was specifically enriched in the RDX-degrading samples. Analysis of the accumulation of RDX-degradation products reveals that during active RDX degradation, there is a transient increase in the concentration of the degradation products MNX, DNX, TNX, and NDAB. The accumulation of these degradation products suggests that RDX is degraded via sequential reduction of the nitro functional groups followed by abiotic ring-cleavage. Here, the results suggest that strict anaerobic conditions are needed to stimulate RDX degradation under the TA-16 site-specific conditions.

Download or read book Kinetic and Ecological Distribution of Soil Microbial Communities as a Function of Attachment written by Alexa N. Rihana-Abdallah and published by . This book was released on 2000 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Microbial Communities and Intrinsic Biodegradation of Chlorinated Aliphatic Hydrocarbon contaminated Groundwater written by Andrew Glucksman and published by . This book was released on 1998 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sequential Anaerobic Aerobic Biodegradation of Trichloroethylene and 1 4 Dioxane written by Alexandra LaPat Polasko and published by . This book was released on 2017 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chlorinated ethenes, such as trichloroethylene (TCE) and their stabilizers, such as 1,4- dioxane, are widespread groundwater contaminants. Bioremediation can be an effective approach, but opposing redox conditions favored by chlorinated ethane-and 1,4-dioxane- degrading bacteria pose a challenge for their concurrent bioremediation. We engineered a microbial community composed of the anaerobic chlorinated ethene-degrading consortium (KB-1i ) and aerobic (Pseudonocardia dioxanivorans CB1190 (CB1190)) bacterial strain, which uses 1,4-dioxane. After anaerobic incubation and TCE reduction, CB1190 + KB-1i coculture was viable and rapidly biodegraded 1,4-dioxane in the presence of oxygen. Aerobic biodegradation of cis-1,2-dichloroethylene (cDCE) by CB1190 was also described. As a plume disperses downgradient, the redox conditions change from anaerobic (source zone) to aerobic (leading edge). The results from this study demonstrate that the engineered microbial community can survive redox changes and biodegrade chlorinated ethenes and 1,4-dioxane. This approach could reduce the cost, energy, and substrates required for in-situ bioremediation of contaminant mixtures.

Download or read book Biodegradation of Groundwater Pollutants chlorinated Hydrocarbons in Vegetated Wetlands written by Christina Lynn Powell and published by . This book was released on 2010 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Acetonitrile on RDX Biodegradation in an Unsaturated Surface Soil written by David B. Ringelberg and published by . This book was released on 2005 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Microbial Diversity in a Hydrocarbon and Chlorinated solvent contaminated Aquifer Undergoing Intrinsic Bioremediation written by Michael A. Dojka and published by . This book was released on 1998 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: A culture-independent molecular phylogenetic approach was used to survey constituents of microbial communities associated with an aquifer contaminated with hydrocarbons (mainly jet fuel) and chlorinated solvents undergoing intrinsic bioremediation. Samples were obtained from three redox zones: methanogenic, methanogenic-sulfate reducing, and iron or sulfate reducing. Small-subunit rRNA genes were amplified directly from aquifer material DNA by PCR with universally conserved or Bacteria- or Archaea-specific primers and were cloned. A total of 812 clones were screened by restriction fragment length polymorphisms (RFLP), approximately 50% of which were unique. All RFLP types that occurred more than once in the libraries, as well as many of the unique types, were sequenced. A total of 104 (94 bacterial and 10 archaeal) sequence types were determined. Of the 94 bacterial sequence types, 10 have no phylogenetic association with known taxonomic divisions and are phylogenetically grouped in six novel division level groups (candidate divisions WS1 to WS6); 21 belong to four recently described candidate divisions with no cultivated representatives (OP5, OP8, OP10, and OP11); and 63 are phylogenetically associated with 10 well-recognized divisions. The physiology of two particularly abundant sequence types obtained from the methanogenic zone could be inferred from their phylogenetic association with groups of microorganisms with a consistent phenotype. One of these sequence types is associated with the genus Syntrophus; Syntrophus spp. produce energy from the anaerobic oxidation of organic acids, with the production of acetate and hydrogen. The organism represented by the other sequence type is closely related to Methanosaeta spp., which are known to be capable of energy generation only through aceticlastic methanogenesis. We hypothesize, therefore, that the terminal step of hydrocarbon degradation in the methanogenic zone of the aquifer is aceticlastic methanogenesis and that the microorganisms represented by these two sequence types occur in syntrophic association.

Download or read book Bioaugmentation for Groundwater Remediation written by Hans F. Stroo and published by Springer Science & Business Media. This book was released on 2012-10-02 with total page 421 pages. Available in PDF, EPUB and Kindle. Book excerpt: ​This volume provides a review of the past 10 to 15 years of intensive research, development and demonstrations that have been on the forefront of developing bioaugmentation into a viable remedial technology. This volume provides both a primer on the basic microbial processes involved in bioaugmentation, as well as a thorough summary of the methodology for implementing the technology. This reference volume will serve as a valuable resource for environmental remediation professionals who seek to understand, evaluate, and implement bioaugmentation.

Download or read book Biodegradation and Bioconversion of Hydrocarbons written by Kirsten Heimann and published by Springer. This book was released on 2016-11-10 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book details three main topics: the screening and characterization of hydrocarbons from air, soil and water; technologies in the biodegradation of hydrocarbons; and the bioconversion of hydrocarbons for biofuel/chemicals, as well as recent developments in the remediation of hydrocarbons and their environmental benefits. The first section focuses on screening methods, qualitative and quantitative analysis of hydrocarbons from soil, air and water environments, speciation of hydrocarbons, and natural bioremediation strategies in such environments. The second section examines technologies for removing hydrocarbon contaminants from various environments, especially advanced technologies for the removal of hydrocarbons and in-situ and ex-situ remediation strategies and problems, as well as concrete case studies. The last section, covering the bioconversion of hydrocarbons for biofuel/chemicals, highlights the biochemicals and bioproducts developed from hydrocarbons, with a particular focus on biochemical and chemical technologies used to produce biopolymers, biofuel precursors and commodity chemicals from hydrocarbons.

Download or read book Biodegradation of Nitroaromatic Compounds written by Jim C. Spain and published by Springer Science & Business Media. This book was released on 2013-11-21 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the past five years increased awareness of environmental contamination by nitroaromatic compounds has led to a dramatic increase in research on their biodegradation. The resulting discoveries have markedly extended our understanding of degradation mecha nisms and pathways in bacteria and fungi. Futhermore, this new basic knowledge promises the development of field applications of biodegradation systems for nitroaromatic com pounds. In May of 1994, an International Symposium on the Biodegradation of Nitro aromatic Compounds was held in Las Vegas, Nevada. This symposium brought together the scientists at the frontiers of research into the biodegradation of nitro aromatic compounds. The invited speakers were asked to review their area of expertise and write a critical, comprehensive synthesis of their work and related work by others. This book is the result of their efforts. The emphasis of the reviews is on basic research in biodegradation and biotransfor mation. Therefore, the reactions of nitroaromatic compounds in plants, animals, bacteria, fungi, soil, and even nonbiological systems are considered. The goal of the work is to provide the reader with an appreciation of the tremendous range of possibilities for metabolism of aromatic nitro compounds and the experimental approaches used to understand them. This volume should be of interest to biochemists, microbiologists, engineers, toxicologists, and anyone interested in the behavior of synthetic chemicals in the environment or in living systems. Furthermore, a variety of commercial applications can be envisioned for some of the reactions described here.

Download or read book Emerging and Eco Friendly Approaches for Waste Management written by Ram Naresh Bharagava and published by Springer. This book was released on 2018-05-25 with total page 443 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rapid industrialization is a serious concern in the context of a healthy environment. With the growth in the number of industries, the waste generated is also growing exponentially. The various chemical processes operating in the manufacturing industry generate a large number of by-products, which are largely harmful and toxic pollutants and are generally discharged into the natural water bodies. Once the pollutants enter the environment, they are taken up by different life forms, and because of bio-magnification, they affect the entire food chain and have severe adverse effects on all life forms, including on human health. Although, various physico-chemical and biological approaches are available for the removal of toxic pollutants, unfortunately these are often ineffective and traditional clean up practices are inefficient. Biological approaches utilizing microorganisms (bacterial/fungi/algae), green plants or their enzymes to degrade or detoxify environmental pollutants such as endocrine disruptors, toxic metals, pesticides, dyes, petroleum hydrocarbons and phenolic compounds, offer eco- friendly approaches. Such eco-friendly approaches are often more effective than traditional practices, and are safe for both industry workers as well as environment. This book provides a comprehensive overview of various toxic environmental pollutants from a variety natural and anthropogenic sources, their toxicological effects on the environment, humans, animals and plants as well as their biodegradation and bioremediation using emerging and eco-friendly approaches (e.g. Anammox technology, advanced oxidation processes, membrane bioreactors, membrane processes, GMOs), microbial degradation (e.g. bacteria, fungi, algae), phytoremediation, biotechnology and nanobiotechnology. Offering fundamental and advanced information on environmental problems, challenges and bioremediation approaches used for the remediation of contaminated sites, it is a valuable resource for students, scientists and researchers engaged in microbiology, biotechnology and environmental sciences.

Download or read book Biodegradation of Nitroaromatic Compounds and Explosives written by Jim C. Spain and published by CRC Press. This book was released on 2000-06-14 with total page 451 pages. Available in PDF, EPUB and Kindle. Book excerpt: Filled with practical applications and research, Biodegradation of Nitroaromatic Compounds and Explosives presents an international perspective on environmental contamination from explosives. It covers biodegradation strategies for DNT and a wide variety of other nitroaromatic compounds of environmental significance and makes the information access

Download or read book Bioremediation of Pollutants written by Vijai Singh and published by Elsevier. This book was released on 2020-05-30 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bioremediation of Pollutants: From Genetic Engineering to Genome Engineering provides insights into genetic and genome engineering strategies in bioremediation, covering a wide range of microorganisms that are key to the removal of pollutants. The book includes discussions on root engineering, transgenic plants, metagenomics, bioreactors, molecular biology tools, genome editing, synthetic biology, microbial indicators, biosurfactants, biofilms, genetically modified organisms, and engineered fungi and bacteria. Presented by top experts in the field, this resource captures the essence and diversity of bioremediation methodologies in a single source. Students and beginners in environmental science, researchers, soil scientists, genetic and genome engineers, stakeholders and policymakers interested in improving this rapidly growing area of research will find this resource extremely useful. - Draws together research from eminent scientists from across the globe in the areas of phytoremediation and microbial remediation - Includes case studies of engineered bacterial remediation - Covers the genome editing CRISPR-Cas9 system that has been less explored in plants and microorganisms