Download or read book Anaerobic Biodegradation of Chlorinated Benzenes and Hexachlorocyclohexane by Mixed Microbial Cultures Derived from Contaminated Field Sites written by Luz Adriana Puentes Jacome and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bioremediation of Chlorinated Solvents written by Robert E. Hinchee and published by . This book was released on 1995 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil and groundwater contamination stemming from the release of various chlorinated compounds into the environment is a significant and difficult site remediation challenge. The articles in this collection discuss the use of aerobic and anaerobic biological degradation to dehalogenate sites contaminated with pesticides and chlorinated solvents such as trichloroethylene, tetrachloroethene, tetrachloromethene, perchloroethylene, carbon tetrachloride, pentachlorophenol, and chlorinated benzene. Bench- and field-scale studies of the biological processes associated with in situ dechlorination of soil and aquifers are described. Discussed are the uses of microcosm studies and numerical simulation of dechlorination to manage system operation. Site characteristics (e.g., hydraulic properties, temperature, nitrogen availability) and their effect on the stability of the methanotrophic community are examined. Methods discussed include the use of air venting, alternative electron donors, biofilm reactors, surfactants, municipal digester sludge, iron enhancement, and sulfate reduction to improve conditions for the microbial consortia that effect dechlorination.
Download or read book Engineered Approaches to in Situ Bioremediation of Chlorinated Solvents written by and published by DIANE Publishing. This book was released on 2000 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Anaerobic Microbial Transformation of Aromatic Hydrocarbons and Mixtures of Aromatic Hydrocarbons and Halogenated Solvents written by Elizabeth A. Edwards and published by . This book was released on 1992 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anaerobic microbial transformation of monoaromatic hydrocarbons (MAH), chlorinated benzenes (CB), and mixtures of MAH and CB, as well as MAH and chlorinated aliphatic solvents (tetrachloroethylene -- PCE, and carbon tetrachloride -CT) was studied in laboratory microcosms derived from hydrocarbon-contaminated groundwater aquifers. Some MAH, such as toluene and o- xylene, were completely degraded to CO2 and CH4 by mixed methanogenic cultures from a creosote-contaminated aquifer. This degradation was inhibited by the addition of accessory electron acceptors (oxygen, nitrate, sulfate), indicating acclimation of the microbial community to methanogenic conditions. The addition of preferred substrates, such as acetate, propionate, methanol, fatty acids, glucose, casamino acids, pepton, yeast extract, or acetone also inhibited MAH degradation, indicating that the presence of natural organic substrates may preclude anaerobic biodegradation of MAH in situ. Cyclohexane, CT, and high concentrations of toluene and o-xylene had a toxic effect Under sulfate-reducing conditions, several MAH -toluene, all three xylene isomers, and benzene were mineralized to CO2, by microorganisms from a petroleum-contaminated, sulfidogenic aquifer. Whereas-toluene and xylenes were sequentially degraded in a mixture, benzene was degraded only if alone, or slowly transformed in a mixture with toluene. This explains previously reported recalcitrance of benzene under anaerobic conditions. Anaerobic Transformation, Monoaromatic Hydrocarbons, Chlorobenzenes, Carbon Tetrachloride, Tetrachloroethylene, Mixtures, Methanogenic, Sulfate-Reducing.
Download or read book Biochemistry of microbial degradation written by Colin Ratledge and published by Springer. This book was released on 2012-10-25 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt: Life on the planet depends on microbial activity. The recycling of carbon, nitrogen, sulphur, oxygen, phosphate and all the other elements that constitute living matter are continuously in flux: microorganisms participate in key steps in these processes and without them life would cease within a few short years. The comparatively recent advent of man-made chemicals has now challenged the environment: where degradation does not occur, accumulation must perforce take place. Surprisingly though, even the most recalcitrant of molecules are gradually broken down and very few materials are truly impervious to microbial attack. Microorganisms, by their rapid growth rates, have the most rapid turn-over of their DNA of all living cells. Consequently they can evolve altered genes and therefore produce novel enzymes for handling "foreign" compounds - the xenobiotics - in a manner not seen with such effect in other organisms. Evolution, with the production of micro-organisms able to degrade molecules hitherto intractable to breakdown, is therefore a continuing event. Now, through the agency of genetic manipulation, it is possible to accelerate this process of natural evolution in a very directed manner. The time-scale before a new microorganism emerges that can utilize a recalcitrant molecule has now been considerably shortened by the application of well-understood genetic principles into microbiology. However, before these principles can be successfully used, it is essential that we understand the mechanism by which molecules are degraded, otherwise we shall not know where best to direct these efforts.
Download or read book Biodegradation of Chlorinated Ethenes in Mixed Waste Streams written by and published by . This book was released on 2004 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes research conducted from 04/01/01 to 08/31/04 with support from the US Army Research Office DoD-EPSCoR program. The goal of the research was to study the biodegradation of chloroethenes under serial anaerobic/aerobic conditions. In the system used water flowed through a contact chamber containing chloroethenes. Contaminated water was then pumped through a sediment column. From the sediment column the water flowed into an aerated chamber. Chloroethenes concentrations were determined in samples from the contact chamber the sediment column and the aerobic chamber. We tested means for establishing anaerobiosis in the sediment column two sparging gas mixtures addition of lactate as a growth substrate control of conditions in the aerobic chamber and the presence of a hydrocarbon fuel mixture as a co-contaminant. Results indicated that a N2:H2 gas mixture stimulated POE degradation. We also found that the addition of exogenous lactic acid (2 mM) and the presence of petroleum hydrocarbons in reactor feed water resulted in 99.6% removal of PCE and 99.2% reduction in the total molar concentration of chloroethenes. In the last year of the research we established mixed microbial cultures in which vinyl chloride disappearance was concomitant with an increase in chloride concentration and biomass accumulation.
Download or read book In Situ Bioremediation written by National Research Council and published by National Academies Press. This book was released on 1993-02-01 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: In situ bioremediationâ€"the use of microorganisms for on-site removal of contaminantsâ€"is potentially cheaper, faster, and safer than conventional cleanup methods. But in situ bioremediation is also clouded in uncertainty, controversy, and mistrust. This volume from the National Research Council provides direction for decisionmakers and offers detailed and readable explanations of: the processes involved in in situ bioremediation, circumstances in which it is best used, and methods of measurement, field testing, and modeling to evaluate the results of bioremediation projects. Bioremediation experts representing academic research, field practice, regulation, and industry provide accessible information and case examples; they explore how in situ bioremediation works, how it has developed since its first commercial use in 1972, and what research and education efforts are recommended for the future. The volume includes a series of perspective papers. The book will be immediately useful to policymakers, regulators, bioremediation practitioners and purchasers, environmental groups, concerned citizens, faculty, and students.
Download or read book Organohalide Respiring Bacteria written by Lorenz Adrian and published by Springer. This book was released on 2016-08-03 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the current state of knowledge concerning bacteria that use halogenated organic compounds as respiratory electron acceptors. The discovery of organohalide-respiring bacteria has expanded the range of electron acceptors used for energy conservation, and serves as a prime example of how scientific discoveries are enabling innovative engineering solutions that have transformed remediation practice. Individual chapters provide in-depth background information on the discovery, isolation, phylogeny, biochemistry, genomic features, and ecology of individual organohalide-respiring genera, including Dehalococcoides, Dehalogenimonas, Dehalobacter, Desulfitobacterium and Sulfurospirillum, as well as organohalide-respiring members of the Deltaproteobacteria. The book introduces readers to the fascinating biology of organohalide-respiring bacteria, offering a valuable resource for students, engineers and practitioners alike.
Download or read book Agrindex written by and published by . This book was released on 1995 with total page 1088 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Management of Microbial Resources in the Environment written by Abdul Malik and published by Springer Science & Business Media. This book was released on 2013-02-26 with total page 535 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume details the exploration, collection, characterization, evaluation and conservation of microbes for sustainable utilization in the development of the global as well as national economies, e.g. in agriculture, ecosystems, environments, industry and medicine. Many research institutes and universities all over the world carry out microbiological and biotechnological research, which generates substantial genomic resources such as cDNA libraries, gene constructs, promoter regions, transgenes and more valuable assets for gene discovery and transgenic product development. This work provides up-to-date information on the management of microbial resources in the environment. It also covers the ecology of microorganisms in natural and engineered environments. In trying to understand microbial interactions it further focuses on genomic, metagenomic and molecular advances, as well as on microbial diversity and phylogeny; ecological studies of human, animal and plant microbiology and disease; microbial processes and interactions in the environment; and key technological advances. Though not intended to serve as an encyclopedic review of the subject, the various chapters investigate both theoretical and practical aspects and provide essential basic information for future research to support continued development.
Download or read book Toxicological Profile for Polycyclic Aromatic Hydrocarbons written by and published by . This book was released on 1995 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Biodegradation and Bioremediation of Industrial Waste written by Ram Chandra and published by CRC Press. This book was released on 2015-03-24 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: Addresses a Global Challenge to Sustainable DevelopmentAdvances in Biodegradation and Bioremediation of Industrial Waste examines and compiles the latest information on the industrial waste biodegradation process and provides a comprehensive review. Dedicated to reducing pollutants generated by agriculturally contaminated soil, and plastic waste fr
Download or read book Biotechnology for Waste and Wastewater Treatment written by Nicholas P. Cheremisinoff and published by Elsevier. This book was released on 1997-12-31 with total page 247 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book examines the practices used or considered for biological treatment of water/waste-water and hazardous wastes. The technologies described involve conventional treatment processes, their variations, as well as future technologies found in current research. The book is intended for those seeking an overview to the biotechnological aspects of pollution engineering, and covers the major topics in this field. The book is divided into five major sections and references are provided for those who wish to dig deeper.
Download or read book Soil pollution a hidden reality written by Food and Agriculture Organization of the United Nations and published by Food & Agriculture Org.. This book was released on 2018-04-30 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document presents key messages and the state-of-the-art of soil pollution, its implications on food safety and human health. It aims to set the basis for further discussion during the forthcoming Global Symposium on Soil Pollution (GSOP18), to be held at FAO HQ from May 2nd to 4th 2018. The publication has been reviewed by the Intergovernmental Technical Panel on Soil (ITPS) and contributing authors. It addresses scientific evidences on soil pollution and highlights the need to assess the extent of soil pollution globally in order to achieve food safety and sustainable development. This is linked to FAO’s strategic objectives, especially SO1, SO2, SO4 and SO5 because of the crucial role of soils to ensure effective nutrient cycling to produce nutritious and safe food, reduce atmospheric CO2 and N2O concentrations and thus mitigate climate change, develop sustainable soil management practices that enhance agricultural resilience to extreme climate events by reducing soil degradation processes. This document will be a reference material for those interested in learning more about sources and effects of soil pollution.
Download or read book Compound specific Stable Isotope Analysis written by Maik A Jochmann and published by Royal Society of Chemistry. This book was released on 2015-11-09 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of Compound-specific Stable Isotope Analysis (CSIA) is increasing in many areas of science and technology for source allocation, authentication, and characterization of transformation reactions. Until now, there have been no textbooks available for students with an analytical chemical background or basic introductory books emphasising the instrumentation and theory. This book is the first to focus solely on stable isotope analysis of individual compounds in sometimes complex mixtures. It acts as both a lecture companion for students and a consultant for advanced scientists in fields including forensic and environmental science. The book starts with a brief history of the field before going on to explain stable isotopes from scratch. The different ways to express isotope abundances are introduced together with isotope effects and isotopic fractionation. A detailed account of the required technical equipment and general procedures for CSIA is provided. This includes sections on derivatization and the use of microextraction techniques in GC-IRMS. The very important topic of referencing and calibration in CSIA is clearly described. This differs from approaches used in quantitative analysis and is often difficult for the newcomer to comprehend. Examples of successful applications of CSIA in food authenticity, forensics, archaeology, doping control, environmental science, and extraterrestrial materials are included. Applications in isotope data treatment and presentation are also discussed and emphasis is placed on the general conclusions that can be drawn from the uses of CSIA. Further instrumental developments in the field are highlighted and selected experiments are introduced that may act as a basis for a short practical course at graduate level.
Download or read book Toxicological Profile for Hexachlorobutadiene written by and published by . This book was released on 1994 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
