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Sample records for phenol bioremediation system

  1. Bacterial Community Structure and Physiological State within an Industrial Phenol Bioremediation System

    PubMed Central

    Whiteley, Andrew S.; Bailey, Mark J.

    2000-01-01

    The structure of bacterial populations in specific compartments of an operational industrial phenol remediation system was assessed to examine bacterial community diversity, distribution, and physiological state with respect to the remediation of phenolic polluted wastewater. Rapid community fingerprinting by PCR-based denaturing gradient gel electrophoresis (DGGE) of 16S rDNA indicated highly structured bacterial communities residing in all nine compartments of the treatment plant and not exclusively within the Vitox biological reactor. Whole-cell targeting by fluorescent in situ hybridization with specific oligonucleotides (directed to the α, β and γ subclasses of the class Proteobacteria [α-, β-, and γ-Proteobacteria, respectively], the Cytophaga-Flavobacterium group, and the Pseudomonas group) tended to mirror gross changes in bacterial community composition when compared with DGGE community fingerprinting. At the whole-cell level, the treatment compartments were numerically dominated by cells assigned to the Cytophaga-Flavobacterium group and to the γ-Proteobacteria. The α subclass Proteobacteria were of low relative abundance throughout the treatment system whilst the β subclass of the Proteobacteria exhibited local dominance in several of the processing compartments. Quantitative image analyses of cellular fluorescence was used as an indicator of physiological state within the populations probed with rDNA. For cells hybridized with EUB338, the mean fluorescence per cell decreased with increasing phenolic concentration, indicating the strong influence of the primary pollutant upon cellular rRNA content. The γ subclass of the Proteobacteria had a ribosome content which correlated positively with total phenolics and thiocyanate. While members of the Cytophaga-Flavobacterium group were numerically dominant in the processing system, their abundance and ribosome content data for individual populations did not correlate with any of the measured chemical

  2. Systems biology approach to bioremediation

    SciTech Connect

    Chakraborty, Romy; Wu, Cindy H.; Hazen, Terry C.

    2012-06-01

    Bioremediation has historically been approached as a ‘black box’ in terms of our fundamental understanding. Thus it succeeds and fails, seldom without a complete understanding of why. Systems biology is an integrated research approach to study complex biological systems, by investigating interactions and networks at the molecular, cellular, community, and ecosystem level. The knowledge of these interactions within individual components is fundamental to understanding the dynamics of the ecosystem under investigation. Finally, understanding and modeling functional microbial community structure and stress responses in environments at all levels have tremendous implications for our fundamental understanding of hydrobiogeochemical processes and the potential for making bioremediation breakthroughs and illuminating the ‘black box’.

  3. Biofouling effects on in situ TCE bioremediation by phenol utilizers

    SciTech Connect

    MacDonald, T.R.; Kitanidis, P.K.

    1995-12-31

    In situ bioremediation involves stimulating the growth of bacteria within the contaminated region of an aquifer to break down the contaminants. This large bacteria population often can have the unwanted effect of clogging the porous media. The clogging reduces the porosity and the hydraulic conductivity of the soil. These hydrodynamic changes can affect the flow of groundwater used to deliver nutrients to the bacteria in the contaminated region of the aquifer. The authors developed a mathematical model to study the impact of biofouling on a recirculation well flow system used to mix nutrients with contaminated groundwater. The insights gained from this examination can aid in designing a system to minimize biofouling problems.

  4. Self-bioremediation of cork-processing wastewaters by (chloro)phenol-degrading bacteria immobilised onto residual cork particles.

    PubMed

    del Castillo, I; Hernández, P; Lafuente, A; Rodríguez-Llorente, I D; Caviedes, M A; Pajuelo, E

    2012-04-15

    Cork manufacturing is a traditional industry in Southern Europe, being the main application of this natural product in wine stoppers and insulation. Cork processing begins at boiling the raw material. As a consequence, great volumes of dark wastewaters, with elevated concentrations of chlorophenols, are generated, which must be depurated through costly physicochemical procedures before discarding them into public water courses. This work explores the potential of bacteria, isolated from cork-boiling waters storage ponds, in bioremediation of the same effluent. The bacterial population present in cork-processing wastewaters was analysed by DGGE; low bacterial biodiversity was found. Aerobic bacteria were isolated and investigated for their tolerance against phenol and two chlorophenols. The most tolerant strains were identified by sequencing 16S rDNA. The phenol-degrading capacity was investigated by determining enzyme activities of the phenol-degrading pathway. Moreover, the capacity to form biofilms was analysed in a microtitre plate assay. Finally, the capacity to form biofilms onto the surface of residual small cork particles was evaluated by acridine staining followed by epifluorescence microscopy and by SEM. A low-cost bioremediation system, using phenol-degrading bacteria immobilised onto residual cork particles (a by-product of the industry) is proposed for the remediation of this industrial effluent (self-bioremediation). PMID:22265252

  5. BIOREMEDIATION

    EPA Science Inventory

    Bioremediation is a method for using the activities of microorganisms and-or plants to transform organic or inorganic compounds that may be harmful to humans, animals, plants or the environment to compounds that are less harmful. In many instances the toxic compounds may be compl...

  6. Biotechnological tools to improve bioremediation of phenol by Acinetobacter sp. RTE1.4.

    PubMed

    Paisio, Cintia E; Talano, Melina A; González, Paola S; Magallanes-Noguera, Cynthia; Kurina-Sanz, Marcela; Agostini, Elizabeth

    2016-09-01

    The use of native bacteria is a useful strategy to decontaminate industrial effluents as well as the environment. Acinetobacter sp. RTE1.4 was previously isolated from polluted environments and constitutes a promising alternative for this purpose due to its capability to remove phenol from synthetic solutions and industrial effluents. In this work, this strain was identified at species level as A. tandoii RTE1.4. Phenol degradation pathway was studied and some reaction intermediates were detected, confirming that this strain degraded phenol through ortho-cleavage of the aromatic ring. Phenol removal assays were carried out in a stirred tank bioreactor and a complete degradation of the contaminant was achieved after only 7 h, at an aeration rate of 3 vvm and at agitation of 600 rpm. Moreover, this bacterium was immobilized into calcium alginate beads and an increase in phenol biodegradation with respect to free cells was observed. The immobilized cells were reused for four consecutive cycles and stored at 4°C for 9 months, during which phenol removal efficiency was maintained. Post-removal solutions were evaluated by Microtox® test, showing a toxicity reduction after bacterial treatment. These findings demonstrated that A. tandoii RTE1.4 might be considered as a useful biotechnological tool for an efficient treatment of different solutions contaminated with phenol in bioreactors, using either free or immobilized cells. PMID:26853946

  7. Full-scale Daramend{trademark} bioremediation of industrial soils containing chlorinated phenols and PAHs

    SciTech Connect

    Seech, A.G.; Bucens, P.G.; Bergeron, D.

    1994-12-31

    Daramend{trademark} bioremediation was developed under the sponsorship of, and is owned by, the Government of Canada. Grace Dearborn Inc. has acquired the license for worldwide application of this technology; which has been successfully used at full-scale to remediate soils containing chlorophenols, polynuclear aromatic hydrocarbons (PAHS) and petroleum hydrocarbons. Over the course of four years (1991--1994), soil was treated under a variety of conditions. During ex-situ treatment, the mean total chlorophenol concentration in excavated soil was reduced from 702 mg/kg to less than the criterion established by the Canadian Council of Ministers of the Environment (CCME) for industrial soil (5 mg/kg). In the same soil the total PAH concentration was reduced from 1.442 me/kg to 35 mg/kg. and the concentrations of all PAH isomers were reduced to less than the CCME criteria for industrial soil (i.e. 10 mg/kg for carcinogenic isomers). Standard toxicological tests, including earthworm mortality and seed germination, were performed on soil taken from the treated area and the control area after completion of the bioremediation. The tests indicated that Daramend treatment had reduced or eliminated the soil`s toxicity.

  8. Potential of the salt-tolerant laccase-producing strain Trichoderma viride Pers. NFCCI-2745 from an estuary in the bioremediation of phenol-polluted environments.

    PubMed

    Divya, L M; Prasanth, G K; Sadasivan, C

    2014-06-01

    Industrialization causes the generation of phenolic pollutants in the environment. The ability of laccases to oxidize phenolic compounds and reduce molecular oxygen to water has led to intensive studies on these enzymes. Although salt-tolerant fungi are potential sources of enzymes for industrial applications, they have been inadequately explored for laccase production. This study describes the isolation of a salt- and phenol-tolerant strain of Trichoderma sp. with the ability to produce laccase, and thus with the potential for industrial applications. The coconut husk retting ground in the estuaries of Kerala, India, a saline environment highly polluted with phenolic compounds, was selected for isolating the fungus. Enhanced laccase production was observed at 5-10 ppt salinity. The organism could grow even at 30 ppt salinity with reduced biomass production and laccase secretion. The optimum concentration of different phenolic compounds for enhanced laccase secretion ranged between 20 and 80 mg L(-1) . As the concentration of phenolic compounds increased beyond 200 mg L(-1) , the enzyme activity decreased and was completely inhibited at 800 mg L(-1) . The tolerance of Trichoderma viride Pers. NFCCI-2745 to salinity and various phenolic compounds can be utilized in the bioremediation of highly saline and phenolic compound-rich industrial effluents. PMID:23712577

  9. Application of two bacterial strains for wastewater bioremediation and assessment of phenolics biodegradation.

    PubMed

    Paisio, Cintia E; Quevedo, María R; Talano, Melina A; González, Paola S; Agostini, Elizabeth

    2014-08-01

    The use of native bacteria is a useful strategy to decontaminate industrial effluents. In this work, two bacterial strains isolated from polluted environments constitutes a promising alternative since they were able to remove several phenolic compounds not only from synthetic solutions but also from effluents derived from a chemical industry and a tannery which are complex matrices. Acinetobacter sp. RTE 1.4 showed ability to completely remove 2-methoxyphenol (1000 mg/L) while Rhodococcus sp. CS 1 not only degrade the same concentration of this compound but also removed 4- chlorophenol, 2,4-dichlorophenol and pentachlorophenol with high efficiency. Moreover, both bacteria degraded phenols naturally present or even exogenously added at high concentrations in effluents from the chemical industry and a tannery in short time (up to 5 d). In addition, a significant reduction of biological oxygen demand and chemical oxygen demand values was achieved after 7 d of treatment for both effluents using Acinetobacter sp. RTE 1.4 and Rhodococcus sp. CS1, respectively. These results showed that Acinetobacter sp. RTE1.4 and Rhodococcus sp. CS 1 might be considered as useful biotechnological tools for an efficient treatment of different effluents, since they showed wide versatility to detoxify these complex matrices, even supplemented with high phenol concentrations. PMID:24956773

  10. Limitation of point source pesticide pollution: results of bioremediation system.

    PubMed

    Spanoghe, P; Maes, A; Steurbaut, W

    2004-01-01

    Groundwater and surface water is at risk of contamination from the use of some agricultural pesticides. In many circumstances pesticide contamination of water resources is more likely to result from point sources than from diffuse sources following approved application to crops in the field. Such point sources include areas on farms where pesticides are handled, filled into sprayers or where sprayers are washed down. To overcome this way of contamination different kind of bio-remediation systems are nowadays in development. In Flanders, Belgium two pilot plants of bioremediation systems for the in situ retention and/or degradation of pesticides were installed. Both systems were based on the Phytobac concept, a watertight excavation filled with straw, peat, compost and soil. The channel was made in the bottom from plastic foil. All kinds of spray rests were captured by the phytobacs. This study focuses on what level pesticides leach, bio-degrade or are retained by the filling of the phytobac. The soil-properties of the filling were investigated. Pesticide tracers were added for monitoring to both phytobacs. Soil and water samples were taken during one year. Pesticides are retained at least for one month by the filling of the phytobac. Almost no pesticide leached out. In winter hardly any pesticide degradation was observed in the filling of the phytobac. In summer no detectable pesticides were still left in the phytobacs. PMID:15756863

  11. DEMONSTRATION BULLETIN: NEW YORK STATE MULTI-VENDOR BIOREMEDIATION - R.E. WRIGHT ENVIRONMENTAL, INC.'S IN-SITU BIOREMEDIATION TREATMENT SYSTEM

    EPA Science Inventory

    The R.E. Wright Environmental, Inc.‘s (REWEI) In-situ Bioremediation Treatment System is an in-situ bioremediation technology for the treatment of soils contaminated with organic compounds. According to the Developer, contaminated soils are remediated in-situ by stimulating the a...

  12. Investigation of chitosan-phenolics systems as wood adhesives.

    PubMed

    Peshkova, Svetlana; Li, Kaichang

    2003-04-24

    Chitosan-phenolics systems were investigated as wood adhesives. Adhesion between two pieces of wood veneer developed only when all three components-chitosan, a phenolic compound, and laccase-were present. For the adhesive systems containing a phenolic compound with only one phenolic hydroxyl group, adhesive strengths were highly dependent upon the chemical structures of phenolic compounds used in the system and the relative oxidation rates of the phenolic compounds by laccase. The adhesive strengths were also directly related to the viscosity of the adhesive systems. However, for the adhesive systems containing a phenolic compound with two or three phenolic hydroxyl groups adjacent to each other, no correlations among adhesive strengths, relative oxidation rates of the phenolic compounds by laccase, and viscosities were observed. The adhesion mechanisms of these chitosan-phenolics systems were proposed to be similar to those of mussel adhesive proteins. PMID:12697397

  13. Biomining active cellulases from a mining bioremediation system.

    PubMed

    Mewis, Keith; Armstrong, Zachary; Song, Young C; Baldwin, Susan A; Withers, Stephen G; Hallam, Steven J

    2013-09-20

    Functional metagenomics has emerged as a powerful method for gene model validation and enzyme discovery from natural and human engineered ecosystems. Here we report development of a high-throughput functional metagenomic screen incorporating bioinformatic and biochemical analyses features. A fosmid library containing 6144 clones sourced from a mining bioremediation system was screened for cellulase activity using 2,4-dinitrophenyl β-cellobioside, a previously proven cellulose model substrate. Fifteen active clones were recovered and fully sequenced revealing 9 unique clones with the ability to hydrolyse 1,4-β-D-glucosidic linkages. Transposon mutagenesis identified genes belonging to glycoside hydrolase (GH) 1, 3, or 5 as necessary for mediating this activity. Reference trees for GH 1, 3, and 5 families were generated from sequences in the CAZy database for automated phylogenetic analysis of fosmid end and active clone sequences revealing known and novel cellulase encoding genes. Active cellulase genes recovered in functional screens were subcloned into inducible high copy plasmids, expressed and purified to determine enzymatic properties including thermostability, pH optima, and substrate specificity. The workflow described here provides a general paradigm for recovery and characterization of microbially derived genes and gene products based on genetic logic and contemporary screening technologies developed for model organismal systems. PMID:23906845

  14. Bioremediation of a PAH-contaminated gasworks site with the Ebiox vacuum heap system

    SciTech Connect

    Eiermann, D.R.; Bolliger, R.

    1995-12-31

    A former gasworks site in the industrial city of Winterthur, Switzerland, was extremely contaminated with polycyclic aromatic hydrocarbons (PAHs); benzene, toluene, ethylbenzene, and xylenes (BTEX); phenols; ammonia; and mineral oils. Three vacuum heaps, with a total volume of 10,500 m{sup 3} of contaminated soil, were bioremediated during 1993/94. Separating excavated soil material into different soil qualities was of particular importance because of the pathway definition of the specific soil material. Excavation of contamination took longer than 10 months, delivering continuously different contaminated soil-type material for bioremediation. Conditioning and subsequent biostimulation of the large soil volumes were the prerequisites for most advanced milieu optimization. The degradation results demonstrated the potential for successful application of bioremediation on former industrial sites. PAH-concentration reductions ranged from 75 to 83% for the soil values and from 87 to 98% for the elution values. Soil and elution target qualities were met within 6 to 12 months, depending on initial PAH-concentration and soil structure. The achieved target quality for the bioremediated soil allowed subsequent reuse as high-value backfill material for the ongoing building project.

  15. Transport, fate and bioremediation of PCBs in freshwater systems

    SciTech Connect

    Birge, W.J.; Price, D.; Robison, A. |

    1995-12-31

    PCB monitoring studies were conducted on four riverine systems that varied in order, gradient, and substrate composition. Accumulation of PCBs was greater in fine-grained sediments with organic carbon content of 1 percent or more. Due to the short residence time of PCBs in water, downstream transport occurred mostly via erosion, suspension and resuspension of sediments and floodplain soils. Residues of PCBs in fish were lowest in the green sunfish and other species, higher in black bass, and highest in bottom feeders, (e.g., channel catfish, carp). Carp and catfish were the poorest indicators of real-time contamination but more useful in assessing historical conditions. Differences in PCB half-life in fish correlated with lipid content. Sunfish were the best indicators of current levels of contamination. PCB body burden in these species decreased markedly after curtailment of PCB outfall. Residues at or above 2 mg/Kg in sunfish decreased to 0.5 mg/Kg or less within 12 to 18 months. Percent tissue lipid was a major factor affecting the rate of metabolic degradation of PCBs in fish. High lipid content may prolong the biological half-life of PCBS, whereas low content may correlate with more rapid degradation, depending on the species. Sunfish, due to their localized range, lower lipid content, and ability to metabolize PCBs may be useful tools in the bioremediation of freshwater systems. They feed largely on primary consumers (e.g. detritivores, herbivores); are adaptable to a wide variety of warm water habitats; and management practices have been well established.

  16. Optimalisation and feasability of bioremediation systems for the processing of spray losses of pesticides.

    PubMed

    De Wilde, T; Spanoghe, P; Ryckeboer, J; Springael, D; Jaeken, P

    2006-01-01

    Contamination of ground and surface water puts pressure on the use of pesticides. Pesticide contamination of water can often be linked to point sources rather than to diffuse sources. Examples of such point sources are areas on farms where pesticides are handled, filled into sprayers and where sprayers are cleaned. To reduce contamination from these point sources, different kinds of bio-remediation systems are in various member states of the EU. Bioremediation is the use of living organisms, primarily micro-organisms, to degrade the environmental contaminants into less toxic forms. In this study, the behaviour of six different pesticides with varying physico-chemical properties on substrates used in a bioremediation system is studied. The adsorption of individual pesticides on the substrates is determined. After determination of the adsorption coefficient Kd, it could be concluded for metalaxyl that coco chips had the highest sorption capacity, followed by straw, compost, willow chopping and a sandy loam soil. PMID:17390767

  17. Superior cottonwood and eucalyptus clones for biomass production in wastewater biomass production in wastewater bioremediation systems

    SciTech Connect

    Rockwood, D.L.; Pisano, S.M.; McConnell, W.V.

    1996-12-31

    Fast-growing cottonwood and Eucalyptus species have wastewater bioremediation potential. To estimate genetic variation in cottonwood`s response to sewage effluent, 10 clones were planted at Tallahassee in April 1992. Progenies and/or clones of E. Ampligolia (EA). E. Camaldulensis (EC), and E. Grandis (EG) were planted in a dry stormwater retention/bioremediation pond constructed in June 1993 at Tampa. Genetic variability within cottonwood and Eucalyptus species was observed and should be utilized to optimize biomass production and nutrient uptake in wastewater bioremediation applications. On good sites with freeze risk in northern Florida, three cottonwood clones are particularly productive. While as many as four EC and EG clones are promising, one EG clone appears superior for stormwater remediation, systems in central Florida.

  18. System for enhanced longevity of in situ microbial filter used for bioremediation

    DOEpatents

    Carman, M. Leslie; Taylor, Robert T.

    2000-01-01

    An improved method for in situ microbial filter bioremediation having increasingly operational longevity of an in situ microbial filter emplaced into an aquifer. A method for generating a microbial filter of sufficient catalytic density and thickness, which has increased replenishment interval, improved bacteria attachment and detachment characteristics and the endogenous stability under in situ conditions. A system for in situ field water remediation.

  19. DEMONSTRATION BULLETIN: EX-SITU ANAEROBIC BIOREMEDIATION SYSTEM: DINOSEB - J.R. SIMPLOT COMPANY

    EPA Science Inventory

    The J.R. Simplot Ex-situ Anaerobic Bioremediation System is a technology designed to destroy nitroaromatic compounds without forming any toxic intermediates. The nitroaromatic compound of interest during this demonstration was dinoseb (2-sec-butyl-4,6-dinitrophenol) an agricul...

  20. Phenol

    Integrated Risk Information System (IRIS)

    Phenol ; CASRN 108 - 95 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effects )

  1. Rhamnolipids enhance marine oil spill bioremediation in laboratory system.

    PubMed

    Chen, Qingguo; Bao, Mutai; Fan, Xiaoning; Liang, Shengkang; Sun, Peiyan

    2013-06-15

    This paper presents a simulated marine oil spill bioremediation experiment using a bacterial consortium amended with rhamnolipids. The role of rhamnolipids in enhancing hydrocarbon biodegradation was evaluated via GC-FID and GC-MS analysis. Rhamnolipids enhanced total oil biodegradation efficiency by 5.63%, with variation in normal alkanes, polyaromatic hydrocarbons (PAHs) and biomakers biodegradation. The hydrocarbons biodegradation by bacteria consortium overall follows a decreasing order of PAHs>n-alkanes>biomarkers, while in different order of PAHs>biomarkers>n-alkanes when rhamnolipids was used, and the improvement in the removal efficiency by rhamnolipids follows another order of biomarkers>n-alkanes>PAHs. Rhamnolipids played a negative role in degradation of those hydrocarbons with relatively volatile property, such as n-alkanes with short chains, PAHs and sesquiterpenes with simple structure. As to the long chain normal alkanes and PAHs and biomakers with complex structure, the biosurfactant played a positive role in these hydrocarbons biodegradation. PMID:23566561

  2. An adsorption-release-biodegradation system for simultaneous biodegradation of phenol and ammonium in phenol-rich wastewater.

    PubMed

    Wang, Ying; Chen, Hu; Liu, Yu-Xiang; Ren, Rui-Peng; Lv, Yong-Kang

    2016-07-01

    The feasibility of simultaneous biodegradation of phenol and ammonium in phenol-rich wastewater was evaluated in a reusable system, which contained macroporous adsorption resin and Alcaligenes faecalis strain WY-01. In the system, up to 6000mg/L phenol could be completely degraded by WY-01; meanwhile, 99.03±3.95% of ammonium was removed from the initial concentration of 384mg/L. This is the first study to show the capability of single strain in simultaneous removal of ammonium and phenol in wastewater containing such high concentrations of phenol. Moreover, the resin was regenerated during the biodegradation process without any additional manipulations, indicating the system was reusable. Furthermore, enzyme assay, gene expression patterns, HPLC-MS and gas chromatography analysis confirmed that phenol biodegradation accompanied with aerobic nitrifier denitrification process. Results imply that the reusable system provides a novel strategy for more efficient biodegradation of phenol and ammonium contained in some particular industrial wastewater. PMID:27060247

  3. Overview of on-farm bioremediation systems to reduce the occurrence of point source contamination.

    PubMed

    De Wilde, Tineke; Spanoghe, Pieter; Debaer, Christof; Ryckeboer, Jaak; Springael, Dirk; Jaeken, Peter

    2007-02-01

    Contamination of ground and surface water puts pressure on the use of pesticides. Pesticide contamination of water can often be linked to point sources rather than to diffuse sources. Examples of such point sources are areas on farms where pesticides are handled and filled into sprayers, and where sprayers are cleaned. To reduce contamination from these point sources, different kinds of bioremediation system are being researched in various member states of the EU. Bioremediation is the use of living organisms, primarily microorganisms, to degrade the environmental contaminants into less toxic forms. The systems available for biocleaning of pesticides vary according to their shape and design. Up till now, three systems have been extensively described and reported: the biobed, the Phytobac and the biofilter. Most of these constructions are excavations or different sizes of container filled with biological material. Typical overall clean-up efficiency exceeds 95%, realising even more than 99% in many cases. This paper provides an overview of the state of the art of these bioremediation systems and discusses their construction, efficiency and drawbacks. PMID:17199234

  4. Design Of Bioremediation Systems For Groundwater (Aerobic and Anaerobic Plus Representative Case Studies)

    EPA Science Inventory

    The attached presentation discusses the fundamentals of bioremediation in the subsurface. The basics of aerobic, cometabolic, and anaerobic bioremediation are presented. Case studies from the Delaware Sand & Gravel Superfund Site, Dover Cometabolic Research Project and the SABR...

  5. The use of modern on-site bioremediation systems to reduce crude oil contamination on oilfield properties

    SciTech Connect

    Hildebrandt, W.W. ); Wilson, S.B. )

    1991-02-01

    Oil-field properties frequently have areas in which the soil has been degraded with crude oil. Soil contaminated in this manner is often considered either a hazardous waste or designated waste under regulatory guidelines. As a result, there is often concern about an owner's liabilities and the financial institution's liabilities whenever oilfield properties are transferred to new operators, abandoned, or converted to other uses such as real estate. There is also concern about the methods and relative costs to remediate soil which has been contaminated with crude oil. Modern, well-designed, soil bioremediation systems are cost effective for the treatment of crude oil contamination, and these systems can eliminate an owner's subsequent liabilities. Compared to traditional land-farming practices, a modern on-site bioremediation system (1) requires significantly less surface area, (2) results in lower operating costs, and (3) provides more expeditious results. Compared to excavation and off-site disposal of the contaminated soil, on-site bioremediation will eliminate subsequent liabilities and is typically more cost effective. Case studies indicate that o-site bioremediation systems have been successful at reducing the crude oil contamination in soil to levels which are acceptable to regulatory agencies in less than 10 weeks. Total costs for on-site bioremediation has ranged from $35 to $40 per cubic yard of treated soil, including excavation.

  6. Enhancing pesticide degradation using indigenous microorganisms isolated under high pesticide load in bioremediation systems with vermicomposts.

    PubMed

    Castillo Diaz, Jean Manuel; Delgado-Moreno, Laura; Núñez, Rafael; Nogales, Rogelio; Romero, Esperanza

    2016-08-01

    In biobed bioremediation systems (BBSs) with vermicomposts exposed to a high load of pesticides, 6 bacteria and 4 fungus strains were isolated, identified, and investigated to enhance the removal of pesticides. Three different mixtures of BBSs composed of vermicomposts made from greenhouse (GM), olive-mill (OM) and winery (WM) wastes were contaminated, inoculated, and incubated for one month (GMI, OMI and WMI). The inoculums maintenance was evaluated by DGGE and Q-PCR. Pesticides were monitored by HPLC-DAD. The highest bacterial and fungal abundance was observed in WMI and OMI respectively. In WMI, the consortia improved the removal of tebuconazole, metalaxyl, and oxyfluorfen by 1.6-, 3.8-, and 7.7-fold, respectively. The dissipation of oxyfluorfen was also accelerated in OMI, with less than 30% remaining after 30d. One metabolite for metalaxyl and 4 for oxyfluorfen were identified by GC-MS. The isolates could be suitable to improve the efficiency of bioremediation systems. PMID:27136610

  7. Enhancing bioremediation

    SciTech Connect

    Koenigsberg, S.

    1997-02-01

    Oxygen is often the limiting factor in aerobic bioremediation. Without adequate oxygen, contaminant degradation will either cease or proceed by highly inefficient anaerobic processes. Researchers at Regenesis Bioremediation Products recently develope a technology to combat this problem, Oxygen Release Compound (ORC) a unique formulation of magnesium peroxide release oxygen slowly when hydrated. ORC is idea for supporting bioremediation of underground storage tank releases. ORC treatment represents a low intensity approach to remediation - simple, passive, low-cost, long term enhancement of a natural attenuation. 1 fig.

  8. The design and management of system components for in situ methanotrophic bioremediation of chlorinated hydrocarbons

    SciTech Connect

    Lombard, K.H.; Borthen, J.W.; Hazen, T.C.

    1992-12-31

    The successful operation of an in situ bioremediation system is inherent within its design. Well-organized system components enable ease of maintenance, limited down time, and relatively rapid data acquisition. The design effort in this project focused on injection of a low-pressure air/methane mixture into a horizontal well below the water table, a methane-blending system that provided control of the injected mixture, redundant safety interlocks, vapor-phase extraction from a second horizontal well, and an off-gas treatment system that provided efficient thermal catalytic oxidation of the extracted contaminant vapors. The control instrumentation provided sufficient redundancies to allow the system to remain in operation in the event of a component failure, and equally important, the safe shut down of the system should any designed safety parameters be exceeded (i.e., high methane concentration). Final design approval took into consideration the reliability of the equipment and the components specified. Product knowledge and proper application limited the risk of a component or system failure while providing a safe, efficient, and cost-effective remediation system. Microprocessor data acquisition and system control were integrated with an autodialer to provide 24 hr emergency response and operation without on-site supervision. This integrated system also insured accurate data analysis and minimum downtime. Since operations commenced, the system has operated a total of 7,760 hours out of the possible 8,837 hours available. This equates to an operating efficiency of 87.8%.

  9. Bioremediation of Crude Oil Contaminated Desert Soil: Effect of Biostimulation, Bioaugmentation and Bioavailability in Biopile Treatment Systems.

    PubMed

    Benyahia, Farid; Embaby, Ahmed Shams

    2016-02-01

    This work was aimed at evaluating the relative merits of bioaugmentation, biostimulation and surfactant-enhanced bioavailability of a desert soil contaminated by crude oil through biopile treatment. The results show that the desert soil required bioaugmentation and biostimulation for bioremediation of crude oil. The bioaugmented biopile system led to a total petroleum hydrocarbon (TPH) reduction of 77% over 156 days while the system with polyoxyethylene (20) sorbitan monooleate (Tween 80) gave a 56% decrease in TPH. The biostimulated system with indigenous micro-organisms gave 23% reduction in TPH. The control system gave 4% TPH reduction. The addition of Tween 80 led to a respiration rate that peaked in 48 days compared to 88 days for the bioaugmented system and respiration declined rapidly due to nitrogen depletion. The residual hydrocarbon in the biopile systems studied contained polyaromatics (PAH) in quantities that may be considered as hazardous. Nitrogen was found to be a limiting nutrient in desert soil bioremediation. PMID:26891314

  10. Bioremediation of Crude Oil Contaminated Desert Soil: Effect of Biostimulation, Bioaugmentation and Bioavailability in Biopile Treatment Systems

    PubMed Central

    Benyahia, Farid; Embaby, Ahmed Shams

    2016-01-01

    This work was aimed at evaluating the relative merits of bioaugmentation, biostimulation and surfactant-enhanced bioavailability of a desert soil contaminated by crude oil through biopile treatment. The results show that the desert soil required bioaugmentation and biostimulation for bioremediation of crude oil. The bioaugmented biopile system led to a total petroleum hydrocarbon (TPH) reduction of 77% over 156 days while the system with polyoxyethylene (20) sorbitan monooleate (Tween 80) gave a 56% decrease in TPH. The biostimulated system with indigenous micro-organisms gave 23% reduction in TPH. The control system gave 4% TPH reduction. The addition of Tween 80 led to a respiration rate that peaked in 48 days compared to 88 days for the bioaugmented system and respiration declined rapidly due to nitrogen depletion. The residual hydrocarbon in the biopile systems studied contained polyaromatics (PAH) in quantities that may be considered as hazardous. Nitrogen was found to be a limiting nutrient in desert soil bioremediation. PMID:26891314

  11. Processing and Properties of a Phenolic Composite System

    NASA Technical Reports Server (NTRS)

    Hou, Tan-Hung; Bai, J. M.; Baughman, James M.

    2006-01-01

    Phenolic resin systems generate water as a reaction by-product via condensation reactions during curing at elevated temperatures. In the fabrication of fiber reinforced phenolic resin matrix composites, volatile management is crucial in producing void-free quality laminates. A commercial vacuum-bag moldable phenolic prepreg system was selected for this study. The traditional single-vacuum-bag (SVB) process was unable to manage the volatiles effectively, resulting in inferior voidy laminates. However, a double vacuum bag (DVB) process was shown to afford superior volatile management and consistently yielded void-free quality parts. The DVB process cure cycle (temperature /pressure profiles) for the selected composite system was designed, with the vacuum pressure application point carefully selected, to avoid excessive resin squeeze-outs and achieve the net shape and target resin content in the final consolidated laminate parts. Laminate consolidation quality was characterized by optical photomicrography for the cross sections and measurements of mechanical properties. A 40% increase in short beam shear strength, 30% greater flexural strength, 10% higher tensile and 18% higher compression strengths were obtained in composite laminates fabricated by the DVB process.

  12. Cometabolic bioremediation

    SciTech Connect

    Hazen, Terry C.

    2009-02-15

    Cometabolic bioremediation is probably the most under appreciated bioremediation strategy currently available. Cometabolism strategies stimulate only indigenous microbes with the ability to degrade the contaminant and cosubstrate e.g. methane, propane, toluene and others. This highly targeted stimulation insures that only those microbes that can degrade the contaminant are targeted, thus reducing amendment costs, well and formation plugging, etc. Cometabolic bioremediation has been used on some of the most recalcitrant contaminants, e.g. PCE, TCE, MTBE, TNT, dioxane, atrazine, etc. Methanotrophs have been demonstrated to produce methane monooxygense, an oxidase that can degrade over 300 compounds. Cometabolic bioremediation also has the advantage of being able to degrade contaminants to trace concentrations, since the biodegrader is not dependent on the contaminant for carbon or energy. Increasingly we are finding that in order to protect human health and the environment that we must remediate to lower and lower concentrations, especially for compounds like endocrine disrupters, thus cometabolism may be the best and maybe the only possibility that we have to bioremediate some contaminants.

  13. Integrated water quality, emergy and economic evaluation of three bioremediation treatment systems for eutrophic water

    EPA Science Inventory

    This study was targeted at finding one or more environmentally efficient, economically feasible and ecologically sustainable bioremediation treatment modes for eutrophic water. Three biological species, i.e. water spinach (Ipomoea aquatica), loach (Misgurus anguillicaudatus) and ...

  14. DEMONSTRATION BULLETIN: GRACE DEARBORN INC. DARAMEND™ BIOREMEDIATION TECHNOLOGY

    EPA Science Inventory

    The DARAMEND™ Bioremediation Technology may be applied to the remediation of soils and sediments contaminated by a wide variety of organic contaminants including chlorinated phenols, polynuclear aromatic hydrocarbons (PAHs), and petroleum hydrocarbons. The technology may be ap...

  15. Fuzzy systems modeling of in situ bioremediation of chlorinatedsolve n ts

    SciTech Connect

    Faybishenko, Boris; Hazen, Terry C.

    2001-09-05

    A large-scale vadose zone-groundwater bioremediationdemonstration was conducted at the Savannah River Site (SRS) by injectingseveral types of gases (ambient air, methane, and nitrous oxide andtriethyl phosphate mixtures) through a horizontal well in the groundwaterat a 175 ft depth. Simultaneously, soil gas was extracted through aparallel horizontal well in the vadose zone at a 80 ft depth Monitoringrevealed a wide range of spatial and temporal variations ofconcentrations of VOCs, enzymes, and biomass in groundwater and vadosezone monitoring boreholes over the field site. One of the powerful modernapproaches to analyze uncertain and imprecise data chemical data is basedon the use of methods of fuzzy systems modeling. Using fuzzy modeling weanalyzed the spatio-temporal TCE and PCE concentrations and methanotrophdensities in groundwater to assess the effectiveness of differentcampaigns of air stripping and bioremediation, and to determine the fuzzyrelationship between these compounds. Our analysis revealed some detailsabout the processes involved in remediation, which were not identified inthe previous studies of the SRS demonstration. We also identified somefuture directions for using fuzzy systems modeling, such as theevaluation of the mass balance of the vadose zone - groundwater system,and the development of fuzzy-ruled methods for optimization of managingremediation activities, predictions, and risk assessment.

  16. Radiation yields of phenol derivatives in nitrobenzene-water systems

    NASA Astrophysics Data System (ADS)

    Čechová, S.; Macášek, F.; Čech, R.

    Radiolysis of nitrobenzene was studied in two-phase systems with water, sulfuric acid and nitric acid solutions. In kinetic regime of radiolysis the two-phase additivity rule was applied to calculate partial radiation yields of p-nitrophenol, m-nitrophenol, p-nitrosophenol, 2,4-dinitrophenol, 2,5-dinitrophenol, o-nitroaniline and o-, m-, p-aminophenols in the systems of various volume ratios. Nitrobenzene phase was found to be several times more reactive than the aqueous one in respect of the phenols and aniline derivatives formation. In the absence of agitation the yields depend strongly on the thickness of the phases irradiated, as it ensues from the diffusion regime theory of radiolysis in biphasic systems, which was illustrated.

  17. Optimal design of an in-situ bioremediation system using support vector machine and particle swarm optimization

    NASA Astrophysics Data System (ADS)

    ch, Sudheer; Kumar, Deepak; Prasad, Ram Kailash; Mathur, Shashi

    2013-08-01

    A methodology based on support vector machine and particle swarm optimization techniques (SVM-PSO) was used in this study to determine an optimal pumping rate and well location to achieve an optimal cost of an in-situ bioremediation system. In the first stage of the two stage methodology suggested for optimal in-situ bioremediation design, the optimal number of wells and their locations was determined from preselected candidate well locations. The pumping rate and well location in the first stage were subsequently optimized in the second stage of the methodology. The highly nonlinear system of equations governing in-situ bioremediation comprises the equations of flow and solute transport coupled with relevant biodegradation kinetics. A finite difference model was developed to simulate the process of in-situ bioremediation using an Alternate-Direction Implicit technique. This developed model (BIOFDM) yields the spatial and temporal distribution of contaminant concentration for predefined initial and boundary conditions. BIOFDM was later validated by comparing the simulated results with those obtained using BIOPLUME III for the case study of Shieh and Peralta (2005). The results were found to be in close agreement. Moreover, since the solution of the highly nonlinear equation otherwise requires significant computational effort, the computational burden in this study was managed within a practical time frame by replacing the BIOFDM model with a trained SVM model. Support Vector Machine which generates fast solutions in real time was considered to be a universal function approximator in the study. Apart from reducing the computational burden, this technique generates a set of near optimal solutions (instead of a single optimal solution) and creates a re-usable data base that could be used to address many other management problems. Besides this, the search for an optimal pumping pattern was directed by a simple PSO technique and a penalty parameter approach was adopted

  18. DESIGN AND OPERATION OF A HORIZONTAL WELL, IN SITU BIOREMEDIATION SYSTEM

    EPA Science Inventory

    A large field demonstration using nutrient addition to stimulate insitu anaerobic bioremediation of chlorinated solvent contaminated soil and ground water was performed at the former U.S. Department of Energy Pinellas Plant in Largo, Florida, from January through June, 1997. Ins...

  19. LABORATORY EVALUATION OF OIL SPILL BIOREMEDIATION PRODUCTS IN SALT AND FRESHWATER SYSTEMS

    EPA Science Inventory

    Ten oil spill bioremediation products were tested in the laboratory for their ability to enhance biodegradation of weathered Alaskan North Slope crude oil in both fresh and salt-water media. The products included: nutrients to stimulate inoculated microorganisms, nutrients plus a...

  20. BIOREMEDIATION IN THE FIELD SEARCH SYSTEM (BFSS) - VERSION 2.0 (DISKETTE)

    EPA Science Inventory

    BFSS is a PC-based software product that provides access to a database of information on waste sites in the United States and Canada where bioremediation is being tested or implemented, or has been completed. BFSS allows users to search the database electronically, view data on s...

  1. Preparation of metallic cation conducting polymers based on sterically hindered phenols containing polymeric systems

    DOEpatents

    Skotheim, T.A.; Okamoto, Yoshiyuki; Lee, H.S.

    1989-11-21

    The present invention relates to ion-conducting solvent-free polymeric systems characterized as being cationic single ion conductors. The solvent-free polymer electrolytes comprise a flexible polymer backbone to which is attached a metal salt, such as a lithium, sodium or potassium salt, of a sterically hindered phenol. The solid polymer electrolyte may be prepared either by (1) attaching the hindered phenol directly to a flexible polymeric backbone, followed by neutralization of the phenolic OH's or (2) reacting the hindered phenol with a polymer precursor which is then polymerized to form a flexible polymer having phenolic OH's which are subsequently neutralized. Preferably the hindered phenol-modified polymeric backbone contains a polyether segment. The ionic conductivity of these solvent-free polymer electrolytes has been measured to be in the range of 10[sup [minus]4] to 10[sup [minus]7] S cm[sup [minus]1] at room temperature.

  2. Preparation of metallic cation conducting polymers based on sterically hindered phenols containing polymeric systems

    DOEpatents

    Skotheim, Terje A.; Okamoto, Yoshiyuki; Lee, Hung S.

    1989-01-01

    The present invention relates to ion-conducting solvent-free polymeric systems characterized as being cationic single ion conductors. The solvent-free polymer electrolytes comprise a flexible polymer backbone to which is attached a metal salt, such as a lithium, sodium or potassium salt, of a sterically hindered phenol. The solid polymer electrolyte may be prepared either by (1) attaching the hindered phenol directly to a flexible polymeric backbone, followed by neutralization of the phenolic OH's or (2) reacting the hindered phenol with a polymer precursor which is then polymerized to form a flexible polymer having phenolic OH's which are subsequently neutralized. Preferably the hindered phenol-modified polymeric backbone contains a polyether segment. The ionic conductivity of these solvent-free polymer electrolytes has been measured to be in the range of 10.sup.-4 to 10.sup.-7 S cm.sup.-1 at room temperature.

  3. Phytoremediation`s role in bioremediation of recalcitrant soil contaminants

    SciTech Connect

    Fletcher, J.S.

    1995-12-31

    Flavonoid and coumarin compounds produced by plants supported the growth of polychlorinated biphenyl (PCB)-degrading bacteria, and the bacteria retained their PCB-degrading properties. Root leachates and washings from mulberry trees also supported the growth of a PCB-degrading bacterium. The release of phenolics into the soil by the network of finely separated plant roots may be thought of as a naturally occurring injection system capable of delivering desired substrates into the soil that fosters the growth and action of PCB-degrading bacteria. However, it is important to recognize that the roots of all plant species do not produce and release equal amounts and kinds of phenolic compounds; therefore, the rhizosphere zone of all plants must not be considered a haven for PCB-degrading bacteria. It may be that only a few plant species have the desired characteristics. Awareness of such species would be extremely valuable, because growing such plants at contaminated sites has the potential of selectively fostering the growth of PCB-degrading bacteria over competing organisms. The outcome could be a sustained population of PCB-degrading bacteria that would degrade PCBs over an extended time period. Plant-microbe systems have the potential of providing inexpensive, ecologically stable bioremediation systems, and thereby play a major role in bioremediation of recalcitrant soil contaminants.

  4. Monitoring system for the study of autotrophic biofilms in bioremediation of polyaromatic compounds

    NASA Astrophysics Data System (ADS)

    Alarie, Jean P.; Bruttig, A.; Miller, Gordon H.; Hill, Walter; Vo-Dinh, Tuan

    1999-02-01

    Bacterial and other natural materials such as plants and algae have received increasing interest for bioremediation efforts. The identificatIon of materials capable of biodegrading or sequestering environmental pollutants offers an attractive alternative to chemical or physical means of remediation. A number of bacteria capable of biodegrAding organic or reducing metal pollutants have received great interest. Similarly, the use of natural plants to absorb pollutants from soil anD liquid samples is another potential approach. Our interest lies in identification of naturally occurring algae and their ability to absorb polyaromatic compounds (PAC) from groundwater sources (i.e. streams). These algae could serve as natural water filters for streams contaminated with Polyaromatic hydrocarbons. Polycyclic aromatic compounds, which comprise a complex class of condensed multi-ring benzenoid compounds, are important environmental pollutants originating from a wide variety of natural and anthropogenic sources. PACs are generally formed during incomplete combustion or pyrolysis of organic matter containing carbon and hydrogen. Because combustion of organic materials is involved in countless natural processes or human activities, PACs are omnipresent and abundant pollutants in air, soil and water. Among energy-related products, fossil fuels are the major sources of PACs. The primary sources of airborne PACs are associated with combustion, coal coking, and petroleum catalytic cracking. Coal and shale conversion also contribute to production of PACs. Production, transportation and, use of synthetic fuels and petroleum products provide emission sources for PACs. In urban environments an significant source of PACs is diesel exhaust. Food cooking and cigarette smoking activities contribute to PAC occurrence in indoor environments. Chemical analysis of PACs is of great environmental and toxicological interest because many of them have been shown to be mutagens and/or potent

  5. Two-Dimensional Gel Electrophoresis: Discovering Biomolecules for Environmental Bioremediation

    NASA Astrophysics Data System (ADS)

    Singh, Om V.; Chandel, Anuj K.

    Environmental contamination has been viewed as an ecological malaise for which bioremediation can be prescribed as a “perfect medicine.” The solution to the problems with bioremediation lies in analyzing to what extent the microbes’ physiological machinery contributes to the degradation process and which biomolecules and their mechanisms are responsible for regulatory factors within the degradation system, such as protein, metabolite, and enzymatic chemical transformation. In the post-genomic era, recent advances in proteomics have allowed us to elucidate many complex biological mechanisms. Two-dimensional gel electrophoresis (2DE) in conjunction with mass spectrometry (MS) can be utilized to identify the biomolecules and their molecular mechanisms in bioremediation. A set of highly abundant global proteins over a pI range 4-7 was separated and compared by size fractionation (25-100 kDa) on 2DE. We identified a set of catabolic proteins, enzymes, and heat shock molecular chaperones associated with the regulatory network that was found to be overexpressed under phenol-stressed conditions. This chapter also offers optimized ideal directions for 2DE, followed by easy-to-follow directions for a protein identification strategy using MALDI-TOF and targeting novel proteins/enzymes for a universal set of experiments.

  6. Efficacy of Acinetobacter sp. B9 for simultaneous removal of phenol and hexavalent chromium from co-contaminated system.

    PubMed

    Bhattacharya, Amrik; Gupta, Anshu; Kaur, Amarjeet; Malik, Darshan

    2014-12-01

    The present study shows the feasibility of a newly isolated strain Acinetobacter sp. B9 for concurrent removal of phenol and Cr (VI) from wastewater. The experiments were conducted in a batch reactor under aerobic conditions. Initially, when mineral salt solution was used as the culture medium, the strain was found to utilize phenol as sole carbon and energy source while no Cr (VI) removal was observed. However, the addition of glucose as co-carbon source resulted in the removal of both toxicants. This co-removal efficiency of the strain was further improved with nutrient-rich media (NB). Optimum co-removal was determined at 188 mg L(-1) of phenol and 3.5 mg L(-1) of Cr (VI) concentrations at pH 7.0. Strain B9 followed the orthometabolic pathway for phenol degradation. Transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR) studies showed sorption of chromium as one of the major mechanisms for Cr (VI) removal by B9 cells. Acinetobacter sp. B9 was later on checked for bioremediation of real tannery wastewater. After 96 h of batch treatment of tannery effluent containing an initial 47 mg L(-1) phenol and 16 mg L(-1) Cr (VI), complete removal of phenol and 87 % reduction of Cr (VI) were attained, showing high efficiency of the bacterial strain for potential application in industrial pollution control. PMID:25062955

  7. Phylogenetic and functional diversity of metagenomic libraries of phenol degrading sludge from petroleum refinery wastewater treatment system

    PubMed Central

    2012-01-01

    In petrochemical refinery wastewater treatment plants (WWTP), different concentrations of pollutant compounds are received daily in the influent stream, including significant amounts of phenolic compounds, creating propitious conditions for the development of particular microorganisms that can rapidly adapt to such environment. In the present work, the microbial sludge from a refinery WWTP was enriched for phenol, cloned into fosmid vectors and pyrosequenced. The fosmid libraries yielded 13,200 clones and a comprehensive bioinformatic analysis of the sequence data set revealed a complex and diverse bacterial community in the phenol degrading sludge. The phylogenetic analyses using MEGAN in combination with RDP classifier showed a massive predominance of Proteobacteria, represented mostly by the genera Diaphorobacter, Pseudomonas, Thauera and Comamonas. The functional classification of phenol degrading sludge sequence data set generated by MG-RAST showed the wide metabolic diversity of the microbial sludge, with a high percentage of genes involved in the aerobic and anaerobic degradation of phenol and derivatives. In addition, genes related to the metabolism of many other organic and xenobiotic compounds, such as toluene, biphenyl, naphthalene and benzoate, were found. Results gathered herein demonstrated that the phenol degrading sludge has complex phylogenetic and functional diversities, showing the potential of such community to degrade several pollutant compounds. This microbiota is likely to represent a rich resource of versatile and unknown enzymes which may be exploited for biotechnological processes such as bioremediation. PMID:22452812

  8. Green synthesis of covellite nanocrystals using biologically generated sulfide: potential for bioremediation systems.

    PubMed

    da Costa, J P; Girão, Ana Violeta; Lourenço, João P; Monteiro, O C; Trindade, Tito; Costa, Maria Clara

    2013-10-15

    This work describes the synthesis of CuS powders in high yield and via an environmentally friendly and straightforward process, under ambient conditions (temperature and pressure), by adding to aqueous copper (II) a nutrient solution containing biologically generated sulfide from sulfate-reducing bacteria (SRB). The powders obtained were composed of CuS (covellite) nanoparticles (NPs) exhibiting a spheroid morphology (<5 nm). The relevance of this method to obtain CuS supported solid substrates has been demonstrated by performing the synthesis in the presence of TiO2 and SiO2 submicron particles. We further extended the work carried out, which substantiates the potential of using biogenic sulfide for the production of covellite nanocrystals and composites, using the effluent of a bioremediation column. Hence, such process results in the synthesis of added value products obtained from metal rich effluents, such as metallurgical and industrial ones, or Acid Mine Drainage (AMD), when associated with bioremediation processes. PMID:23747373

  9. Spatially Oscillating Activity and Microbial Succession of Mercury-Reducing Biofilms in a Technical-Scale Bioremediation System

    PubMed Central

    von Canstein, Harald; Li, Ying; Leonhäuser, Johannes; Haase, Elke; Felske, Andreas; Deckwer, Wolf-Dieter; Wagner-Döbler, Irene

    2002-01-01

    Mercury-contaminated chemical wastewater of a mercury cell chloralkali plant was cleaned on site by a technical-scale bioremediation system. Microbial mercury reduction of soluble Hg(II) to precipitating Hg(0) decreased the mercury load of the wastewater during its flow through the bioremediation system by up to 99%. The system consisted of a packed-bed bioreactor, where most of the wastewater's mercury load was retained, and an activated carbon filter, where residual mercury was removed from the bioreactor effluent by both physical adsorption and biological reduction. In response to the oscillation of the mercury concentration in the bioreactor inflow, the zone of maximum mercury reduction oscillated regularly between the lower and the upper bioreactor horizons or the carbon filter. At low mercury concentrations, maximum mercury reduction occurred near the inflow at the bottom of the bioreactor. At high concentrations, the zone of maximum activity moved to the upper horizons. The composition of the bioreactor and carbon filter biofilms was investigated by 16S-23S ribosomal DNA intergenic spacer polymorphism analysis. Analysis of spatial biofilm variation showed an increasing microbial diversity along a gradient of decreasing mercury concentrations. Temporal analysis of the bioreactor community revealed a stable abundance of two prevalent strains and a succession of several invading mercury-resistant strains which was driven by the selection pressure of high mercury concentrations. In the activated carbon filter, a lower selection pressure permitted a steady increase in diversity during 240 days of operation and the establishment of one mercury-sensitive invader. PMID:11916716

  10. OXIDATION OF PHENOLIC ANTIOXIDANTS IN A RIVER SYSTEM

    EPA Science Inventory

    The phenolic antioxidants are important commercial organic chemicals. Their environmental fate is of significance because of their abundance and usage patterns. This paper reports on the fates of 2,6-di-tert-butylphenol and the methyl and octadecyl esters of 3-(3,5-di-tert-butyl-...

  11. Flow injection-chemiluminescence determination of phenol using potassium permanganate and formaldehyde system

    NASA Astrophysics Data System (ADS)

    Cao, Wei; Mu, Xuemin; Yang, Jinghe; Shi, Wenbo; Zheng, Yongcun

    2007-01-01

    It is found that phenol can react with potassium permanganate in the acidic medium and produce chemiluminescence, which is greatly enhanced by formaldehyde. The optimum conditions for this chemiluminescent reaction are in detail studied using a flow injection system. The experiments indicate that under optimum conditions, the chemiluminescence intensity is linearly related to the concentration of phenol in the range 5.0 × 10 -9 to 1.0 × 10 -6 g mL -1 with a detection limit (3 σ) of 3 × 10 -9 g mL -1. The relative standard deviation is 1.2% for 4.0 × 10 -7 g mL -1 phenol solution in 11 repeated measurements. This method has the advantages of simple operation, fast response and high sensitivity. The method is successfully applied to the determination of phenol in the waste water.

  12. Laboratory method used for bioremediation

    DOEpatents

    Carman, M. Leslie; Taylor, Robert T.

    2000-01-01

    An improved method for in situ microbial filter bioremediation having increasingly operational longevity of an in situ microbial filter emplaced into an aquifer. A method for generating a microbial filter of sufficient catalytic density and thickness, which has increased replenishment interval, improved bacteria attachment and detachment characteristics and the endogenous stability under in situ conditions. A system for in situ field water remediation.

  13. Comparison of adsorption and photo-Fenton processes for phenol and paracetamol removing from aqueous solutions: single and binary systems.

    PubMed

    Rad, Leila Roshanfekr; Haririan, Ismaeil; Divsar, Faten

    2015-02-01

    In the present study, adsorption and photo-Fenton processes have been compared for the removal of phenol and paracetamol from aqueous solutions in a single and binary systems. NaX nanozeolites and cobalt ferrite nanoparticles were used during adsorption and photo-Fenton processes, respectively. Both nanoparticles were synthesized using microwave heating method. The synthesized nanoparticles were characterized using powder X-ray diffraction (XRD) and scanning electronic microscopy (SEM) analysis. Based on results, more than 99% removing percentages of phenol and paracetamol were obtained during photo-Fenton process at initial concentrations of 10, 20, 50, 100 and 200 mg/L of phenol and paracetamol. Moreover, the complete removing of phenol and paracetamol was only achieved at lower initial concentrations than 10 mg/L for phenol and paracetamol during adsorption process. The results showed a significant dependence of the phenol and paracetamol removing on the initial concentrations of phenol and paracetamol for selection of process. The photo-Fenton process could be considered an alternative method in higher initial concentrations of phenol and paracetamol. However, the adsorption process due to economical issue was preferred for phenol and paracetamol removing at lower initial concentrations. The kinetic data of photo-Fenton and adsorption processes were well described using first-order and pseudo-second-order kinetic models. The results of phenol and paracetamol removing in a binary system confirmed the obtained results of single removing of phenol and paracetamol in selection of process. PMID:25448945

  14. Comparison of adsorption and photo-Fenton processes for phenol and paracetamol removing from aqueous solutions: Single and binary systems

    NASA Astrophysics Data System (ADS)

    Rad, Leila Roshanfekr; Haririan, Ismaeil; Divsar, Faten

    2015-02-01

    In the present study, adsorption and photo-Fenton processes have been compared for the removal of phenol and paracetamol from aqueous solutions in a single and binary systems. NaX nanozeolites and cobalt ferrite nanoparticles were used during adsorption and photo-Fenton processes, respectively. Both nanoparticles were synthesized using microwave heating method. The synthesized nanoparticles were characterized using powder X-ray diffraction (XRD) and scanning electronic microscopy (SEM) analysis. Based on results, more than 99% removing percentages of phenol and paracetamol were obtained during photo-Fenton process at initial concentrations of 10, 20, 50, 100 and 200 mg/L of phenol and paracetamol. Moreover, the complete removing of phenol and paracetamol was only achieved at lower initial concentrations than 10 mg/L for phenol and paracetamol during adsorption process. The results showed a significant dependence of the phenol and paracetamol removing on the initial concentrations of phenol and paracetamol for selection of process. The photo-Fenton process could be considered an alternative method in higher initial concentrations of phenol and paracetamol. However, the adsorption process due to economical issue was preferred for phenol and paracetamol removing at lower initial concentrations. The kinetic data of photo-Fenton and adsorption processes were well described using first-order and pseudo-second-order kinetic models. The results of phenol and paracetamol removing in a binary system confirmed the obtained results of single removing of phenol and paracetamol in selection of process.

  15. Stakeholder acceptance analysis: In-well vapor stripping, in-situ bioremediation, gas membrane separation system (membrane separation)

    SciTech Connect

    Peterson, T.

    1995-12-01

    This document provides stakeholder evaluations on innovative technologies to be used in the remediation of volatile organic compounds from soils and ground water. The technologies evaluated are; in-well vapor stripping, in-situ bioremediation, and gas membrane separation.

  16. Principles of Bioremediation Assessment

    NASA Astrophysics Data System (ADS)

    Madsen, E. L.

    2001-12-01

    Although microorganisms have successfully and spontaneously maintained the biosphere since its inception, industrialized societies now produce undesirable chemical compounds at rates that outpace naturally occurring microbial detoxification processes. This presentation provides an overview of both the complexities of contaminated sites and methodological limitations in environmental microbiology that impede the documentation of biodegradation processes in the field. An essential step toward attaining reliable bioremediation technologies is the development of criteria which prove that microorganisms in contaminated field sites are truly active in metabolizing contaminants of interest. These criteria, which rely upon genetic, biochemical, physiological, and ecological principles and apply to both in situ and ex situ bioremediation strategies include: (i) internal conservative tracers; (ii) added conservative tracers; (iii) added radioactive tracers; (iv) added isotopic tracers; (v) stable isotopic fractionation patterns; (vi) detection of intermediary metabolites; (vii) replicated field plots; (viii) microbial metabolic adaptation; (ix) molecular biological indicators; (x) gradients of coreactants and/or products; (xi) in situ rates of respiration; (xii) mass balances of contaminants, coreactants, and products; and (xiii) computer modeling that incorporates transport and reactive stoichiometries of electron donors and acceptors. The ideal goal is achieving a quantitative understanding of the geochemistry, hydrogeology, and physiology of complex real-world systems.

  17. In situ bioremediation using horizontal wells

    SciTech Connect

    1995-04-01

    In Situ Bioremediation (ISB), which is the term used in this report for Gaseous Nutrient Injection for In Situ Bioremediation, remediates soils and ground water contaminated with volatile organic compounds (VOCs) both above and below the water table. ISB involves injection of air and nutrients (sparging and biostimulation) into the ground water and vacuum extraction to remove .VOCs from the vadose zone concomitant with biodegradation of VOCs. The innovation is in the combination of 3 emerging technologies, air stripping, horizontal wells, and bioremediation via gaseous nutrient injection with a baseline technology, soil vapor extraction, to produce a more efficient in situ remediation system.

  18. Case study: Bioremediation in the Aleutian Islands

    SciTech Connect

    Steward, K.J.; Laford, H.D.

    1995-12-31

    This case study describes the design, construction, and operation of a bioremediation pile on Adak Island, which is located in the Aleutian Island chain. Approximately 1,900 m{sup 3} of petroleum-contaminated soil were placed in the bioremediation pile. The natural bioremediation process was enhanced by an oxygen and nutrient addition system to stimulate microbial activity. Despite the harsh weather on the island, after the first 6 months of operation, laboratory analyses of soil samples indicated a significant (80%) reduction in diesel concentrations.

  19. In situ groundwater bioremediation

    SciTech Connect

    Hazen, Terry C.

    2009-02-01

    In situ groundwater bioremediation of hydrocarbons has been used for more than 40 years. Most strategies involve biostimulation; however, recently bioaugmentation have been used for dehalorespiration. Aquifer and contaminant profiles are critical to determining the feasibility and strategy for in situ groundwater bioremediation. Hydraulic conductivity and redox conditions, including concentrations of terminal electron acceptors are critical to determine the feasibility and strategy for potential bioremediation applications. Conceptual models followed by characterization and subsequent numerical models are critical for efficient and cost effective bioremediation. Critical research needs in this area include better modeling and integration of remediation strategies with natural attenuation.

  20. Possible role of laccase from Fusarium incarnatum UC-14 in bioremediation of Bisphenol A using reverse micelles system.

    PubMed

    Chhaya, Urvish; Gupte, Akshaya

    2013-06-15

    Bisphenol A [2,2 bis (4 hydroxyphenyl) propane] is widely used in the variety of industrial and residential applications such as the synthesis of polymers including polycarbonates, epoxy resins, phenol resins, polyesters and polyacrylates. BPA has been recognized as an Endocrine Disrupting Chemicals (EDC), thus it is necessary to assess its biodegradability or fate in the natural environment. In general, environmental pollutant such as BPA does not dissolve in aqueous media, owing to their high hydrophobicity, and hence non-aqueous catalysis can be employed to enhance biodegradability of phenolic environmental pollutant. Purified laccase hosted in reverse micelles using ternary system of isooctane: AOT [Bis (2-ethylhexyl) sulphosuccinate sodium salt)]:water having hydration ratio (Wo) of 30 with protein concentration of 43.5 μg/ml was found to eliminate 91.43% of 200 ppm of Bisphenol A at 50 °C, pH-6.0 when incubated with laccase/Reverse Micelles system for 75 min. GC-MS analysis of isooctane soluble fractions detected the presence of 4,4'-(2 hydroxy propane 1,2 diyl) diphenol, bis (4-hydroxylphenyl) butenal and 2-(1-(4-hydroxyphenyl) vinyl) pent-2-enal indicated degradation of BPA by two oxidation steps and one ring opening step (C-C bond cleavage). Laccase/RM system exhibited several advantages for the oxidative degradation of hydrophobic phenols mainly because of the solubility of either enzyme or substrate was improved in organic media and the stable activity of laccase in organic media was achieved. PMID:23611799

  1. Probing organic matter transfer dynamics in river systems using lignin phenol 14C ages

    NASA Astrophysics Data System (ADS)

    Feng, X.; Vonk, J. E.; Gustafsson, O.; Galy, V.; Holmes, R. M.; Mann, P. J.; Montlucon, D.; Eglinton, T. I.

    2011-12-01

    As an important and ubiquitous component of terrestrial organic matter, lignin is widely dispersed by rivers during the land-ocean transfer. While the distribution and composition of lignin-derived phenols have been extensively investigated, little is known on their radiocarbon age, which carries information on the residence time and/or source of organic matter during fluvial transport. Recently, we have developed a high pressure liquid chromatography-based method of isolating individual lignin phenols for radiocarbon analysis. We employed compound-specific radiocarbon analysis to investigate the provenance and transport of lignin in sedimentary particles from several major river systems that span a range of latitudes spanning Arctic (Mackenzie, Kolyma, Indigirka, Lena, Yenisey, Ob, and Kalix), temperate (Columbia), to tropical regions (Congo and Ganges-Brahmaputra). The radiocarbon age of lignin phenols ranged from modern in the tropical (Congo and Ganges-Brahmaputra) rivers to approximately 4000 years in the Arctic (Kolyma and Indigirka). The latter, while clearly reflecting protracted storage of lignin within Arctic river drainage basins, is much younger than plant wax lipids isolated from the same sediments. This observation indicates that lignin is a relatively rapidly cycling component of the terrestrial organic matter transported by rivers. The general correlation between the radiocarbon age of lignin phenols and the latitude of rivers suggests climatic control over the preservation and storage of lignin within the river drainage basins. Individual lignin phenols were also isolated from the dissolved organic matter from several of these major rivers (including Congo, Fraser, Ganges-Brahmaputra, Mackenzie, and Yangtze, etc.) and compared their composition and radiocarbon age with those in the suspended particles collected from the same river system. Such comparison allows the assessment of lignin fractionation and degradation in the dissolved and particulate

  2. Bioremediation of organic pollutants in a radioactive wastewater

    SciTech Connect

    Oboirien, Bilainu; Molokwane, P.E.; Chirwa, Evans

    2007-07-01

    Bioremediation holds the promise as a cost effective treatment technology for a wide variety of hazardous pollutants. In this study, the biodegradation of organic compounds discharged together with radioactive wastes is investigated. Nuclear process wastewater was simulated by a mixture of phenol and strontium, which is a major radionuclide found in radioactive wastewater. Phenol was used in the study as a model compound due to its simplicity of molecular structure. Moreover, the biodegradation pathway of phenol is well known. Biodegradation studies were conducted using pure cultures of Pseudomonas aeruginosa and Pseudomonas putida. The rate of phenol degradation by both species was found to be higher in the test without strontium. This suggests some degree of inhibition in the degradation of phenol by strontium. There was no phenol degradation in the sterile controls. The results indicate the feasibility of the biodegradation of organic pollutants discharged in radioactive effluents by specialised microbial cultures. (authors)

  3. Optimization of a bioremediation system of soluble uranium based on the biostimulation of an indigenous bacterial community.

    PubMed

    Maleke, Maleke; Williams, Peter; Castillo, Julio; Botes, Elsabe; Ojo, Abidemi; DeFlaun, Mary; van Heerden, Esta

    2015-06-01

    High concentrations of uranium(VI) in the Witwatersrand Basin, South Africa from mining leachate is a serious environmental concern. Treatment systems are often ineffective. Therefore, optimization of a bioremediation system that facilitates the bioreduction of U(VI) based on biostimulation of indigenous bacterial communities can be a viable alternative. Tolerance of the indigenous bacteria to high concentrations of U and the amount of citric acid required for U removal was optimized. Two bioreactor studies which showed effective U(VI) removal more than 99 % from low (0.0037 mg L(-1)) and high (10 mg L(-1)) concentrations of U to below the limit allowed by South African National Standards for drinking water (0.0015 mg L(-1)). The second bioreactor was able to successfully adapt even with increasing levels of U(VI) feed water up to 10 mg L(-1), provided that enough electron donor was available. Molecular biology analyses identified Desulfovibrio sp. and Geobacter sp. among known species, which are known to reduce U(VI). The mineralogical analysis determined that part of the uranium precipitated intracellularly, which meant that the remaining U(VI) was precipitated as U(IV) oxides and TEM-EDS also confirmed this analysis. This was predicted with the geochemical model from the chemical data, which demonstrated that the treated drainage was supersaturated with respect to uraninite > U4O9 > U3O8 > UO2(am). Therefore, the tolerance of the indigenous bacterial community could be optimized to remediate up to 10 mg L(-1), and the system can thus be upscaled and employed for remediation of U(VI) impacted sites. PMID:25548012

  4. Responses of microbial communities to single-walled carbon nanotubes in phenol wastewater treatment systems.

    PubMed

    Qu, Yuanyuan; Ma, Qiao; Deng, Jie; Shen, Wenli; Zhang, Xuwang; He, Zhili; Van Nostrand, Joy D; Zhou, Jiti; Zhou, Jizhong

    2015-04-01

    The expanding use of single-walled carbon nanotubes (SWCNTs) raises environmental concerns. Wastewater treatment systems are potential recipients of SWCNTs containing influent, yet the impacts of SWCNTs on these systems are poorly documented. In this study, the microbial responses to SWCNTs in simulated phenol wastewater treatment systems were investigated. The phenol removal rates were improved in all SWCNTs-treated sequencing batch reactors during the first 20 days, but when facing higher phenol concentration (1000 mg/L) after 60 days, reactors with the highest concentration (3.5 g/L) of SWCNTs exhibited a notably decreased phenol removal capacity. Cell viability tests, scanning electron microscopy analysis and DNA leakage data suggested that SWCNTs protected microbes from inactivation, possibly by producing more bound extracellular polymeric substances (EPS), which could create a protective barrier for the microbes. Illumina sequencing of 16S rRNA gene amplicons revealed that the bacterial diversity did not change significantly except for a minor reduction after the immediate addition of SWCNTs. Bacterial community structure significantly shifted after SWCNTs addition and did not recover afterward. Zoogloea increased significantly upon SWCNTs shocking. At the final stage, Rudaea and Mobilicoccus increased, while Burkholderia, Singulisphaera, Labrys and Mucilaginibacter decreased notably. The shifts of these dominant genera may be associated with altered sludge settling, aromatic degradation and EPS production. This study suggested that SWCNTs exerted protective rather than cytotoxic effects on sludge microbes of phenol wastewater treatment systems and they affected the bacterial community structure and diversity at test concentrations. These findings provide new insights into our understanding of the potential effects of SWCNTs on wastewater treatment processes. PMID:25751159

  5. FINAL REPORT. GENETIC ANALYSIS OF STRESS RESPONSES IN SOIL BACTERIA FOR ENHANCED BIOREMEDIATION OF MIXED CONTAMINANTS

    EPA Science Inventory

    Bioremediation is the technological process whereby biological systems are harnessed toeffect the clean-up of environmental pollutants. Bioremediation has been demonstrated to be anappropriate alternative to conventional clean-up strategies in many cases. For example, aerobicb...

  6. Fungi in Bioremediation

    NASA Astrophysics Data System (ADS)

    Gadd, G. M.

    2001-12-01

    Bioremediation research has concentrated on organic pollutants, although the range of substances that can be transformed or detoxified by microorganisms includes both natural and synthetic organic materials and inorganic pollutants. The majority of applications developed to date involve bacteria, with a distinct lack of appreciation of the potential roles and involvement of fungi in bioremediation, despite clear evidence of their metabolic and morphological versatility. This book highlights the potential of filamentous fungi, including mycorrhizas, in bioremediation and discusses the physiology and chemistry of pollutant transformations.

  7. Persistence of fermentative process to phenolic toxicity in groundwater

    SciTech Connect

    Wu, Y.X.; Lerner, D.N.; Banwart, S.A.; Thornton, S.E.; Pickup, R.W.

    2006-11-15

    The fermentation process is an important component in the biodegradation of organic compounds in natural and contaminated systems. Comparing with terminal electron-accepting processes (TEAPs), however, research on fermentation processes has to some extent been ignored in the past decades, particularly on the persistence of fermentation process in the presence of toxic organic pollutants. Both field and laboratory studies, presented here, showed that microbial processes in a groundwater-based system exhibited a differential inhibitory response to toxicity of phenolic compounds from coal tar distillation, thus resulting in the accumulation of volatile fatty acids (VFAs) and hydrogen. This indicated that fermentation processes could be more resistant to phenol toxicity than the subsequent TEAPs such as methanogenesis and sulfate reduction, thus providing us with more options for enhancing bioremediation processes.

  8. Intrinsic bioremediation modeling to support Superfund site closure

    SciTech Connect

    Bedard, A.H.; Day, M.J.; Johnson, R.H.; Ritter, K.J.; Stancel, S.G.; Thomson, J.A.M.

    1997-09-01

    Closure of the groundwater component of a major Superfund site has been accomplished by a combination of source control, engineered in-situ bioremediation, and subsequent long-term intrinsic bioremediation. Engineered bioremediation outside the source control area resulted in very significant contaminant mass removal. This allowed intrinsic bioremediation to be considered as a passive remedial management method of achieving cleanup objectives after active remediation needed. Modeling demonstrated that intrinsic bioremediation would achieve cleanup objectives (for this site, Federal drinking water standards) within ten years of shutdown of the active bioremediation system. Modeling showed that residual electron acceptors and nutrients distributed in the aquifer during engineered bioremediation greatly enhance the intrinsic bioremediation process. The results of the modeling effort led to the active system being shut down a year ahead of schedule, allowing the project to move into a low-maintenance intrinsic bioremediation and long-term monitoring phase. The modeling demonstration coupled Visual MODFLOW{copyright} and BioTrans{copyright} to simulate groundwater flow, solute transport, and oxygen-limited, multi-species biodegradation. Regional flow evaluation, detailed model sensitivity analyses, and subarea modeling were employed to provide support to model predictions. Predictions will be tested by subsequent progress and compliance monitoring. Site closure began in early 1996.

  9. Lipase-catalyzed synthesis of structured phenolic lipids in solvent-free system using flaxseed oil and selected phenolic acids as substrates.

    PubMed

    Sorour, Noha; Karboune, Salwa; Saint-Louis, Richard; Kermasha, Selim

    2012-04-15

    Structured phenolic lipids (PLs) were obtained by lipase-catalyzed transesterification of flaxseed oil, in a solvent-free system (SFS), with selected phenolic acids, including hydroxylated and/or methoxylated derivatives of cinnamic, phenyl acetic and benzoic acids. A bioconversion yield of 65% was obtained for the transesterification of flaxseed oil with 3,4-dihydroxyphenyl acetic acid (DHPA). However, the effect of the chemical structure of phenolic acids on the transesterification of flaxseed oil in SFS was of less magnitude as compared to that in organic solvent system (OSS). Using DHPA, the APCI-MS analysis confirmed the synthesis of monolinolenyl, dilinolenyl, linoleyl linolenyl and oleyl linolenyl dihydroxyphenyl acetates as phenolic lipids. A significant increase in the enzymatic activity from 200 to 270 nmol of PLs/g solid enzyme/min was obtained upon the addition of the non-ionic surfactant Span 65. However, upon the addition of the anionic surfactant, sodium bis-2-ethylhexyl sulfosuccinate (AOT), and the cationic one, hexadecyltrimethylammonium bromide (CTAB), the enzymatic activity was decreased slightly from 200 to 192 and 190 nmol of PLs/g solid enzyme/min, respectively. The results also showed that the increase in DHPA concentration from 20 to 60 mM resulted in a significant increase in the volumetric productivity (P(V)) from 1.61 to 4.74 mg PLs per mL reaction mixture per day. PMID:22329891

  10. Metabolism of benzene and phenol by a reconstituted purified phenobarbital induced rat liver mixed function oxidase system

    SciTech Connect

    Griffiths, J.C.

    1986-01-01

    Cytochrome P-450 and the electron-donor, NADPH-cytochrome c reductase were isolated from phenobarbital induced rat liver microsomes. Both benzene and its primary metabolite phenol, were substrates for the reconstituted purified phenobarbital induced rat liver mixed function oxidase system. Benzene was metabolized to phenol and the polyhydroxylated metabolites; catechol, hydroquinone and 1,2,4 benzenetriol. Benzene elicited a Type I spectral change upon its interaction with the cytochrome P-450 while phenol's interaction with the cytochrome P-450 produced a reverse Type I spectra. The formation of phenol showed a pH optimum of 7.0 compared with 6.6-6.8 for the production of the polyhyrdoxylated metabolites. Cytochrome P-450 inhibitors, such as metyrapone and SKF 525A, diminished the production of phenol from benzene but not the production of the polyhydroxylated metabolites from phenol. The radical trapping agents, DMSO, KTBA and mannitol, decreased the recovery of polyhydroxylated metabolites, from /sup 14/C-labeled benzene and/or phenol. As KTBA and DMSO interacted with OH. There was a concomitant release of ethylene and methane, which was measured. Desferrioxamine, an iron-chelator and catalase also depressed the recovery of polyhydroxylated metabolites. In summary, benzene and phenol were both substrates for this reconstituted purified enzyme system, but they differed in binding to cytochrome P-450, pH optima and mode of hydroxylation.

  11. A novel integration system of magnetically immobilized cells and a pair of graphite plate-stainless iron mesh electrodes for the bioremediation of coking wastewater.

    PubMed

    Jiang, Bei; Tan, Liang; Ning, Shuxiang; Shi, Shengnan

    2016-09-01

    Magnetically immobilized cells of Comamonas sp. JB coupling with electrode reaction was developed to enhance the treatment efficiency of coking wastewater containing phenol, carbazole (CA), dibenzofuran (DBF), and dibenzothiophene (DBT). The pair of graphite plate-stainless iron mesh electrodes was chosen as the most suitable electrodes. Magnetically immobilized cells coupling with graphite plate-stainless iron mesh electrodes (coupling system) exhibited high degradation activity for all the compounds, which were significantly higher than the sum by single magnetically immobilized cells and electrode reaction at the optimal voltage. Recycling experiments demonstrated that the degradation activity of coupling system increased gradually during eight recycles, indicating that there was a coupling effect between the biodegradation and electrode reaction. Phenol hydroxylase and qPCR assays confirmed that appropriate electrical stimulation could improve phenol hydroxylase activity and promote cells growth. Toxicity assessment suggested the treatment of the coking wastewater by coupling system led to less toxicity than untreated wastewater. PMID:27289060

  12. Bioremediation of mixed microbial mats: System development of mixed contaminants for application at the Savannah River Site. Annual technical progress report, October 1, 1995--September 30, 1996

    SciTech Connect

    Bender, J.; Phillips, P.

    1996-09-24

    The fundamental objective of this project is to develop and field test the mixed microbial mat bioremediation system for decontamination of target sites at SRS. Although microbial mats have performed well in several pilot projects in the past, atypical problems and site characteristics at SRS demand special field designs. In the interest of designing a pilot and locating it at an appropriate site, the project investigators have worked closely with the technical staff at the SREL. We have concluded that the diverse characteristics of contaminations at SRS may dictate testing several pilot designs during the course of this project.

  13. Analysis of phenol degradation in pulsed discharge plasma system based on Back-Propagation artificial neural network model

    NASA Astrophysics Data System (ADS)

    Liu, Chao-hua; Wang, Hui-juan; Yi, Cheng-wu

    2013-03-01

    Due to the advantages of Artificial Neural Network (ANN) for analyzing complex reaction system, the oxidation process of phenol in a pulsed discharge plasma system is simulated using an ANN model. Reaction factors including solution with pH values of 3.6, 5.4 and 9.8, and hydroxyl radicals (·OH) scavengers (Na2CO3 and n-butyl alcohol) are considered, and the changing trends of phenol degradation under various experimental conditions are simulated and predicted by the Back-Propagation (BP) neural network model. The obtained results show that the BP neural network model can effectively predict the degradation efficiency of phenol in the reaction system. According to the results, acidic solution is favourable for phenol oxidation and increase in the Na2CO3 and n-butyl alcohol addition will greatly restrain the phenol degradation. The restraining effect of scavengers on phenol degradation indicates that ·OH is one of most important active species for phenol oxidation in the pulsed discharge plasma system.

  14. Bioassessment of bioremediation products in aquatic systems using cytotoxic and in vitro immune function assays

    SciTech Connect

    Rice, C.D.; Roszell, L.E.; Overstreet, K.B. Jr.; O`Hara, T.M.

    1995-12-31

    Estuarine sediments and overlying water were collected from Back Bay Mississippi and placed in five 7.5 x 61 cm. glass-column mesocosms with a peristaltic recirculating system. Four columns received a sample of artificially weathered Louisiana Crude Oil spiked with either N + P, a PAH-metabolizing bacterial consortium collected in situ, or both. A fifth column excluded oil, bacteria, and nutrients. Aliphatic and aromatic fractions were extracted from each system and diluted in iso-octane. Poecoliopsis Hepatoma Cells (PLHC-1) and Rat Hepatoma Cells (H4IIE) were treated with 1/100--1/800 dilutions of each extract and protein synthesis, RNA synthesis, DNA synthesis, Cytochrome P4501A induction, and viability were determined. {proportional_to}-CD3 and {proportional_to}-IgM-stimulated proliferation of mouse lymphocytes, PWM-stimulated proliferation and PMA-stimulated oxidative burst activity of catfish lymphocytes and phagocytes, respective, were also determined. All extracts were overtly toxic to cell cultures compared to controls at a 1/100 dilution but only aliphatic fractions affected viability at higher dilutions. Aromatic fractions increased protein and RNA synthesis as well as induced P4501A at 1/400 and 1/800 dilutions. Fertilization with P + N increased toxic responses. Lymphocyte proliferation and fish phagocyte responses were more sensitive to aliphatic extracts. This approach may be useful for investigating the toxicity and biological impact of effluents.

  15. Identification of biofloc microscopic composition as the natural bioremediation in zero water exchange of Pacific white shrimp, Penaeus vannamei, culture in closed hatchery system

    NASA Astrophysics Data System (ADS)

    Manan, Hidayah; Moh, Julia Hwei Zhong; Kasan, Nor Azman; Suratman, Suhaimi; Ikhwanuddin, Mhd

    2016-06-01

    Study on the microscopic composition of biofloc in closed hatchery culture system was carried out to determine the interaction between the aggregation flocs in the bioremediation process for the decomposition and degradation of organic matter loaded in the shrimp culture tanks. The study was done for 105 days of culture period in zero water exchange. All of the organic loaded in the culture tanks identified comes from the shrimp feces, uneaten fed, and the decomposed macro- and microorganisms died in the culture tanks. All of the microscopic organisms in the biofloc were identified using Advance microscopes Nikon 80i. From the present study, there were abundances and high varieties of phytoplankton, zooplankton, protozoa, nematodes and algae species identified as aggregates together in the flocs accumulation. All of these microscopic organisms identified implemented the symbiotic process together for food supply, become the algae grazer, act as natural water stabilizer in regulating the nutrients in culture tank and serve as decomposer for dead organic matter in the water environment. Heterotrophic bacteria identified from Pseudomonas and Aeromonas family consumed the organic matter loaded at the bottom of culture tank and converted items through chemical process as useful protein food to be consumed back by the shrimp. Overall it can be concluded that the biofloc organisms identified really contributed as natural bioremediation agents in zero water exchange culture system to ensure the water quality in the optimal condition until the end of culture period.

  16. Accelerated in situ bioremediation of groundwater

    SciTech Connect

    Truex, M.J.; Hooker, B.S.; Anderson, D.B.

    1996-07-01

    In situ bioremediation, as applied in this project, is based on the principal of biostimulation: supplying nutrients to indigenous microbes to stimulate their metabolic activity and subsequent degradation of contaminants. Typically, a network of injection and extraction wells are used to recirculate groundwater into which amendments are added and distributed within the aquifer. The objective of the in situ process is to create in the aquifer a microbially active zone that maximizes contaminant destruction while controlling the distribution of microbial growth. It is important to control microbial growth to avoid plugging the aquifer near the injection well and to establish and sustain maximum treatment zones for each injection well. Figure I illustrates this concept for in situ bioremediation. The technology described herein is innovative in its use of the computer-based Accelerated Bioremediation Design Tool (ABDT) to aid in selecting appropriate system designs and to determine optimal operating strategies. In addition, numerical simulations within the design tool proved to be valuable during remediation operations to determine appropriate changes in the` operating strategy as the bioremediation process progressed. This is particularly important because in situ bioremediation is not a steady- state process, and corrective actions to operating parameters are typically needed to maintain both rapid destruction rates and hydraulic containment.

  17. Erwinia amylovora modifies phenolic profiles of susceptible and resistant apple through its type III secretion system.

    PubMed

    Pontais, Isabelle; Treutter, Dieter; Paulin, Jean-Pierre; Brisset, Marie-Noëlle

    2008-03-01

    Fire blight is a disease affecting Maloideae caused by the necrogenic bacterium Erwinia amylovora, which requires the type III protein secretion system (TTSS) for pathogenicity. Profiles of methanol-extractable leaf phenolics of two apple (Malus x domestica) genotypes with contrasting susceptibility to this disease were analyzed by HPLC after infection. Some qualitative differences were recorded between the constitutive compositions of the two genotypes but in both of them dihydrochalcones accounted for more than 90% of total phenolics. Principal component analysis separated leaves inoculated with a virulent wild-type strain from those inoculated with a non-pathogenic TTSS-defective mutant or with water. The changes in levels of the various groups of phenolics in response to the virulent bacterium were similar between the two genotypes, with a significant decrease of dihydrochalcones and a significant increase of hydroxycinnamate derivatives. Differences between genotypes were, however, recorded in amplitude and kinetic of variation in these groups. Occurrence of oxidation and polymerization reactions is proposed, based on the browning process of infected tissues, but whether some by-products act in defense as toxic compounds remain to be tested. Among direct antibacterial constitutive compounds present in apple leaves, the dihydrochalcone phloretin only was found at levels close to lethal concentrations in both genotypes. However, E. amylovora exhibited the ability to stabilize this compound at sublethal levels even in the resistant apple, rejecting the hypothesis of its involvement in the resistance of this genotype. PMID:18275458

  18. Bioremediation using Gracilaria chouae co-cultured with Sparus macrocephalus to manage the nitrogen and phosphorous balance in an IMTA system in Xiangshan Bay, China.

    PubMed

    Wu, Hailong; Huo, Yuanzi; Han, Fang; Liu, Yuanyuan; He, Peimin

    2015-02-15

    A cage experiment using the red alga Gracilaria chouae co-cultured with the black seabream Sparus macrocephalus in Xiangshan Bay, China was conducted to measure the nutrient flux of the integrated multi-trophic aquaculture (IMTA) system. Results showed that trash fish were the main nutrient input contributor and adult fish were the main nutrient output contributor in the system. Contents of N and P in adult fish accounted for 54.45% and 59.48% of N and P in trash fish and fry, which suggests that 45.55% of N and 40.52% of P generated by fish farming were released into to the water. G. chouae proved to be an efficient bioremediation species in this IMTA system. To balance the excess nutrients generated by the system, 231.09 kg of seedlings should be cultured and 5315.07 kg of adult seaweed should be harvested. PMID:25561001

  19. Bioremediation: A natural solution. [Decontamination of soils and groundwater

    SciTech Connect

    Hicks, B.N.; Caplan, J.A. )

    1993-01-15

    Bioremediation is an attractive remediation alternative because most full-scale bioremediation projects involve cost-effective contaminant treatment on-site. Recently, large scale bioremediation projects have included cleanups of ocean tanker spills, land-based chemical spills, and leaking chemical and petroleum storage tanks. Contaminated matrices have included beaches, soils, groundwater, surface waters (i.e., pits, ponds, lagoons), process waste streams and grease traps. Bioremediation is especially cost-effective when both soil and groundwater matrices are impacted because one remediation treatment system can be design to treat both media simultaneously in place. The primary advantages of in situ bioremediation include: on-site destruction of contaminants; accelerated cleanup time; minimal disruption to operations; lower remediation costs; and reduction of future liability.

  20. Microbial trench-based optofluidic system for reagentless determination of phenolic compounds.

    PubMed

    Sanahuja, David; Giménez-Gómez, Pablo; Vigués, Núria; Ackermann, Tobias Nils; Guerrero-Navarro, Alfons Eduard; Pujol-Vila, Ferran; Sacristán, Jordi; Santamaria, Nidia; Sánchez-Contreras, María; Díaz-González, María; Mas, Jordi; Muñoz-Berbel, Xavier

    2015-04-01

    Phenolic compounds are one of the main contaminants of soil and water due to their toxicity and persistence in the natural environment. Their presence is commonly determined with bulky and expensive instrumentation (e.g. chromatography systems), requiring sample collection and transport to the laboratory. Sample transport delays data acquisition, postponing potential actions to prevent environmental catastrophes. This article presents a portable, miniaturized, robust and low-cost microbial trench-based optofluidic system for reagentless determination of phenols in water. The optofluidic system is composed of a poly(methyl methacrylate) structure, incorporating polymeric optical elements and miniaturized discrete auxiliary components for optical transduction. An electronic circuit, adapted from a lock-in amplifier, is used for system control and interfering ambient light subtraction. In the trench, genetically modified bacteria are stably entrapped in an alginate hydrogel for quantitative determination of model phenol catechol. Alginate is also acting as a diffusion barrier for compounds present in the sample. Additionally, the superior refractive index of the gel (compared to water) confines the light in the lower level of the chip. Hence, the optical readout of the device is only altered by changes in the trench. Catechol molecules (colorless) in the sample diffuse through the alginate matrix and reach bacteria, which degrade them to a colored compound. The absorbance increase at 450 nm reports the presence of catechol simply, quickly (~10 min) and quantitatively without addition of chemical reagents. This miniaturized, portable and robust optofluidic system opens the possibility for quick and reliable determination of environmental contamination in situ, thus mitigating the effects of accidental spills. PMID:25669844

  1. Technical Basis for Assessing Uranium Bioremediation Performance

    SciTech Connect

    PE Long; SB Yabusaki; PD Meyer; CJ Murray; AL N’Guessan

    2008-04-01

    In situ bioremediation of uranium holds significant promise for effective stabilization of U(VI) from groundwater at reduced cost compared to conventional pump and treat. This promise is unlikely to be realized unless researchers and practitioners successfully predict and demonstrate the long-term effectiveness of uranium bioremediation protocols. Field research to date has focused on both proof of principle and a mechanistic level of understanding. Current practice typically involves an engineering approach using proprietary amendments that focuses mainly on monitoring U(VI) concentration for a limited time period. Given the complexity of uranium biogeochemistry and uranium secondary minerals, and the lack of documented case studies, a systematic monitoring approach using multiple performance indicators is needed. This document provides an overview of uranium bioremediation, summarizes design considerations, and identifies and prioritizes field performance indicators for the application of uranium bioremediation. The performance indicators provided as part of this document are based on current biogeochemical understanding of uranium and will enable practitioners to monitor the performance of their system and make a strong case to clients, regulators, and the public that the future performance of the system can be assured and changes in performance addressed as needed. The performance indicators established by this document and the information gained by using these indicators do add to the cost of uranium bioremediation. However, they are vital to the long-term success of the application of uranium bioremediation and provide a significant assurance that regulatory goals will be met. The document also emphasizes the need for systematic development of key information from bench scale tests and pilot scales tests prior to full-scale implementation.

  2. In situ bioremediation of chlorinated solvent with natural gas

    SciTech Connect

    Rabold, D.E.

    1996-12-31

    A bioremediation system for the removal of chlorinated solvents from ground water and sediments is described. The system involves the the in-situ injection of natural gas (as a microbial nutrient) through an innovative configuration of horizontal wells.

  3. Bioremediation of nanomaterials

    DOEpatents

    Chen, Frank Fanqing; Keasling, Jay D; Tang, Yinjie J

    2013-05-14

    The present invention provides a method comprising the use of microorganisms for nanotoxicity study and bioremediation. In some embodiment, the microorganisms are bacterial organisms such as Gram negative bacteria, which are used as model organisms to study the nanotoxicity of the fullerene compounds: E. coli W3110, a human related enterobacterium and Shewanella oneidensis MR-1, an environmentally important bacterium with versatile metabolism.

  4. Comparison of Failure Modes in 2-D and 3-D Woven Carbon Phenolic Systems

    NASA Technical Reports Server (NTRS)

    Rossman, Grant A.; Stackpoole, Mairead; Feldman, Jay; Venkatapathy, Ethiraj; Braun, Robert D.

    2013-01-01

    NASA Ames Research Center is developing Woven Thermal Protection System (WTPS) materials as a new class of heatshields for entry vehicles (Stackpoole). Currently, there are few options for ablative entry heatshield materials, none of which is ideally suited to the planetary probe missions currently of interest to NASA. While carbon phenolic was successfully used for the missions Pioneer Venus and Galileo (to Jupiter), the heritage constituents are no longer available. An alternate carbon phenolic would need to be qualified for probe missions, which is most efficient at heat fluxes greater than those currently of interest. Additional TPS materials such as Avcoat and PICA are not sufficiently robust for the heat fluxes required. As a result, there is a large TPS gap between the materials efficient at very high conditions (carbon phenolic) and those that are effective at low-moderate conditions (all others). Development of 3D Woven TPS is intended to fill this gap, targeting mid-density weaves that could with withstand mid-range heat fluxes between 1100 W/sq cm and 8000 W/sq cm (Venkatapathy (2012). Preliminary experimental studies have been performed to show the feasibility of WTPS as a future mid-range TPS material. One study performed in the mARC Jet Facility at NASA Ames Research Center characterized the performance of a 3D Woven TPS sample and compared it to 2D carbon phenolic samples at ply angles of 0deg, 23.5deg, and 90deg. Each sample contained similar compositions of phenolic and carbon fiber volume fractions for experimental consistency. The goal of this study was to compare the performance of the TPS materials by evaluating resulting recession and failure modes. After exposing both samples to similar heat flux and pressure conditions, the 2D carbon phenolic laminate was shown to experience significant delamination between layers and further pocketing underneath separated layers. The 3D Woven TPS sample did not experience the delamination or pocketing

  5. Bioremediation of Petroleum Hydrocarbon Contaminated Sites

    SciTech Connect

    Fallgren, Paul

    2009-03-30

    environmental parameters on bioremediation is important in designing a bioremediation system to reduce petroleum hydrocarbon concentrations in impacted soils.

  6. In situ microbial filter used for bioremediation

    DOEpatents

    Carman, M. Leslie; Taylor, Robert T.

    2000-01-01

    An improved method for in situ microbial filter bioremediation having increasingly operational longevity of an in situ microbial filter emplaced into an aquifer. A method for generating a microbial filter of sufficient catalytic density and thickness, which has increased replenishment interval, improved bacteria attachment and detachment characteristics and the endogenous stability under in situ conditions. A system for in situ field water remediation.

  7. Effect of two monoterpene phenols on antioxidant defense system in Candida albicans.

    PubMed

    Khan, Amber; Ahmad, Aijaz; Ahmad Khan, Luqman; Padoa, Carolyn J; van Vuuren, Sandy; Manzoor, Nikhat

    2015-03-01

    Thymol and carvacrol from the class of monoterpene phenols are one of the most potent plant essential oil components possessing antimicrobial effects. Known for their wide bioactive spectrum, these positional isomers of isopropyl cresol deplete ergosterol content, compromise membrane permeability, block efflux pumps and restore antifungal susceptibility to fluconazole in resistant Candida strains. Exposure to these natural compounds induces a cascade of stress responses, which are important to comprehend their microbicidal mechanisms. This study evaluates the antioxidant defense response to lower concentrations of thymol and carvacrol in Candida albicans. The antioxidant defense responses in C. albicans are important for developmental mechanisms pertaining to resistance against the immune system, infection establishment and drug resistance. In this view, primary and secondary antioxidant defense enzymes, and oxidative stress markers including glutathione and lipid peroxidation were determined in C. albicans cells exposed to lower concentrations of thymol and carvacrol. These compounds were found to induce oxidative stress and compromised the antioxidant defense system in C. albicans at lower concentrations. This study helps in understanding the 'in cell' antifungal mechanisms of natural monoterpene phenols originating from oxidative stress. Thymol and carvacrol induced membrane deterioration reported earlier, is further explained as a result of a toxic radical cascade mediated by lipid peroxidation. Findings reinforce the observed toxic oxidizing effects of these compounds as a consequence of direct damage to antioxidant components and not to their genetic manipulations. PMID:25681060

  8. Efficient treatment of phenolic wastewater with high salinity using a novel integrated system of magnetically immobilized cells coupling with electrodes.

    PubMed

    Jiang, Bei; Shi, Shengnan; Song, Lun; Tan, Liang; Li, Meidi; Liu, Jiaxin; Xue, Lanlan

    2016-10-01

    A novel integrated system in which magnetically immobilized cells coupled with a pair of stainless iron meshes-graphite plate electrodes has been designed and operated to enhance the treatment performance of phenolic wastewater under high salinity. With NaCl concentration increased, phenol, o-cresol, m-cresol, p-cresol and COD removal rates by integrated system increased significantly, which were obviously higher than the sum of removal rates by single magnetically immobilized cells and electrode reaction. This integrated system exhibited higher removal rates for all the compounds than that by single magnetically immobilized cells during six cycles for reuse, and it still performed better, even when the voltage was cut off. These results indicated that there was a coupling effect between biodegradation and electrode reaction. The investigation of phenol hydroxylase activity and cells concentration confirmed that electrode reaction played an important role in this coupling effect. PMID:27347805

  9. Development and application of the lux gene for environmental bioremediation

    SciTech Connect

    Burlage, R.S.; Yang, Z.; Palmer, R.J.; Khang, Y.

    1996-09-01

    Bioremediation is the use of living systems, usually microorganisms, to treat a quantity of soil or water for the presence of hazardous wastes. Bioremediation has many advantages over other remediation approaches, including cost savings, versatility, and the ability to treat the wastes in situ. In order to study the processes of microbial bioremediation, the authors have constructed bacterial strains that incorporate genetically engineered bioreporter genes. These bioreporter genes allow the bacteria to be detected during in situ processes, as manifested by their ability to bioluminescence or to fluoresce. This bioreporter microorganisms are described, along with the technology for detecting them and the projects which are benefiting from their application.

  10. Bioremediation of contaminated groundwater

    SciTech Connect

    Hazen, T.C.; Fliermans, C.B.

    1992-12-31

    The present invention relates to a method for in situ bioremediation of contaminated soil and groundwater. In particular, the invention relates to remediation of contaminated soil and groundwater by the injection of nutrients to stimulate growth of pollutant-degrading microorganisms. The United States Government has rights in this invention pursuant to Contract No. DE-AC09-89SR18035 between the US Department of Energy and Westinghouse Savannah River Company.

  11. Flight test of carbon-phenolic on a spacecraft launched by the pacemaker vehicle system

    NASA Technical Reports Server (NTRS)

    Walton, T. E., Jr.; Witte, W. G.

    1972-01-01

    Carbon-phenolic material consisting of 50 percent carbon fibers and 50 percent phenolic resin was flight tested on a recoverable spacecraft launched by the Pacemaker vehicle system. The heat shield of the spacecraft was fabricated so that the carbon fibers in the ablator material had different orientations over several areas of the spacecraft. The environment in which the spacecraft was tested produced heating rates on the hemispherical nose up to 13.6 MW/sq m (1200 Btu/sq ft/sec) and stagnation-point pressures up to 1.27 MN/sq m (12.5 atm). The experimental results are presented. Due to high heating rates and possible spallation and mechanical char removal the greatest mass loss occurred in the nose region. Essentially uniform surface recession and char thickness were observed on the conical section of the spacecraft. A comparison of measured heating rates with computed turbulent and laminar heating rates, as well as measurements of sound-pressure fluctuations in the boundary layer obtained with acoustic sensors, indicated that the boundary layer underwent transition. The acoustic sensor provides an interesting new data form for the general study of boundary-layer transition for free-flight investigations.

  12. A green and sensitive method to determine phenols in water and wastewater samples using an aqueous two-phase system.

    PubMed

    Rodrigues, Guilherme Dias; de Lemos, Leandro Rodrigues; da Silva, Luis Henrique Mendes; da Silva, Maria do Carmo Hespanhol; Minim, Luis Antonio; Coimbra, Jane Sélia dos Reis

    2010-01-15

    A greener and more sensitive spectrophotometric procedure has been developed for the determination of phenol and o-cresol that exploits an aqueous two-phase system (ATPS) using a liquid-liquid extraction technique. An ATPS is formed mostly by water and does not require organic solvent. Other ATPS components used in this study were the polymer, polyethylene oxide, and some salts (i.e., Li(2)SO(4), Na(2)SO(4) or K(2)HPO(4)+KOH). The method is based on the reaction between phenol, sodium nitroprusside (NPS) and hydroxylamine hydrochloride (HL) in an alkaline medium (pH 12.0), producing the complex anion [Fe(2)(CN)(10)](10-) that spontaneously concentrates in the top phase of the system. The linear range was 1.50-500microgkg(-1) (R>or=0.9997; n=8) with coefficients of variation equal to 0.38% for phenol and 0.30% for o-cresol (n=5). The method yielded limits of detection (LODs) of 1.27 and 1.88microgkg(-1) and limits of quantification (LOQs) of 4.22 and 6.28microgkg(-1) for phenol and o-cresol, respectively. Recoveries between 95.7% and 107% were obtained for the determination of phenol in natural water and wastewater samples. In addition, excellent agreement was observed between this new ATPS method and the standard 4-aminoantipyrine (4-AAP) method. PMID:20006065

  13. In situ bioremediation of chlorinated solvents.

    PubMed Central

    Semprini, L

    1995-01-01

    Chlorinated solvents and their natural transformation products are the most frequently observed groundwater contaminants in the United States. In situ bioremediation using anaerobic or aerobic co-metabolic processes is a promising means of cleaning up contaminated aquifers. Studies show that under natural conditions trichloroethylene can be anaerobically degraded to dichloroethylene, vinyl chloride, and ethylene. Pilot scale field studies of in situ aerobic co-metabolic transformations have shown that indigenous microbes grown on phenol are more effective at degrading trichloroethylene and cis-1,2-dichloroethylene than microbes grown on methane. Modeling studies support field observations and indicate that the removal of trichloroethylene and cis-dichloroethylene results from the biostimulation of an indigenous microbial population. Field tests and modeling studies indicate that, at high TCE concentration, degradation becomes stoichiometrically limited. PMID:8565895

  14. Type III Secretion System Genes of Dickeya dadantii 3937 Are Induced by Plant Phenolic Acids

    PubMed Central

    Yang, Shihui; Peng, Quan; San Francisco, Michael; Wang, Yongjun; Zeng, Quan; Yang, Ching-Hong

    2008-01-01

    Background Dickeya dadantii is a broad-host range phytopathogen. D. dadantii 3937 (Ech3937) possesses a type III secretion system (T3SS), a major virulence factor secretion system in many Gram-negative pathogens of plants and animals. In Ech3937, the T3SS is regulated by two major regulatory pathways, HrpX/HrpY-HrpS-HrpL and GacS/GacA-rsmB-RsmA pathways. Although the plant apoplast environment, low pH, low temperature, and absence of complex nitrogen sources in media have been associated with the induction of T3SS genes of phytobacteria, no specific inducer has yet been identified. Methodology/Principal Findings In this work, we identified two novel plant phenolic compounds, o-coumaric acid (OCA) and t-cinnamic acid (TCA), that induced the expression of T3SS genes dspE (a T3SS effector), hrpA (a structural protein of the T3SS pilus), and hrpN (a T3SS harpin) in vitro. Assays by qRT-PCR showed higher amounts of mRNA of hrpL (a T3SS alternative sigma factor) and rsmB (an untranslated regulatory RNA), but not hrpS (a σ54-enhancer binding protein) of Ech3937 when these two plant compounds were supplemented into minimal medium (MM). However, promoter activity assays using flow cytometry showed similar promoter activities of hrpN in rsmB mutant Ech148 grown in MM and MM supplemented with these phenolic compounds. Compared with MM alone, only slightly higher promoter activities of hrpL were observed in bacterial cells grown in MM supplemented with OCA/TCA. Conclusion/Significance The induction of T3SS expression by OCA and TCA is moderated through the rsmB-RsmA pathway. This is the first report of plant phenolic compounds that induce the expression T3SS genes of plant pathogenic bacteria. PMID:18698421

  15. Improvement of phenol photodegradation efficiency by a combined g-C3N4/Fe(III)/persulfate system.

    PubMed

    Hu, Jian-Yang; Tian, Ke; Jiang, Hong

    2016-04-01

    Graphite-like C3N4 (g-C3N4) is an efficient visible-light-driven photocatalyst commonly used in dye decolorization with very poor photocatalytic efficiency for degrading recalcitrant organic pollutants, such as phenol. In this study, we designed a g-C3N4/Fe(III)/persulfate system to significantly improve the phenol photodegradation efficacy by combining photocatalysis and light Fenton interaction. The phenol removal ratio and degradation rate of the g-C3N4/Fe(III)/persulfate system are 16.5- and 240-fold higher than those of individual g-C3N4 system. Sulfate radicals [Formula: see text] and H2O2 are detected in the g-C3N4/Fe(III)/persulfate system, suggesting that both radical decomposition and light Fenton interaction play important roles in phenol degradation. The efficient coupled photocatalytic system of g-C3N4 combined with Fe(III) and persulfate shows significant potential for application in large-scale degradation of environmental pollutants. PMID:26802260

  16. Bioremediation of wastewater using microalgae

    NASA Astrophysics Data System (ADS)

    Chalivendra, Saikumar

    Population expansion and industrial development has deteriorated the quality of freshwater reservoirs around the world and has caused freshwater shortages in certain areas. Discharge of industrial effluents containing toxic heavy metals such as Cd and Cr into the environment have serious impact on human, animal and aquatic life. In order to solve these problems, the present study was focused on evaluating and demonstrating potential of microalgae for bioremediation of wastewater laden with nitrogen (N) in the form of nitrates, phosphorous (P) in the form of phosphates, chromium (Cr (VI)) and cadmium (Cd (II)). After screening several microalgae, Chlorella vulgaris and algae taken from Pleasant Hill Lake were chosen as candidate species for this study. The viability of the process was demonstrated in laboratory bioreactors and various experimental parameters such as contact time, initial metal concentration, algae concentration, pH and temperature that would affect remediation rates were studied. Based on the experimental results, correlations were developed to enable customizing and designing a commercial Algae based Wastewater Treatment System (AWTS). A commercial AWTS system that can be easily customized and is suitable for integration into existing wastewater treatment facilities was developed, and capital cost estimates for system including installation and annual operating costs were determined. The work concludes that algal bioremediation is a viable alternate technology for treating wastewater in an economical and sustainable way when compared to conventional treatment processes. The annual wastewater treatment cost to remove N,P is ~26x lower and to remove Cr, Cd is 7x lower than conventional treatment processes. The cost benefit analysis performed shows that if this technology is implemented at industrial complexes, Air Force freight and other Department of Defense installations with wastewater treatment plants, it could lead to millions of dollars in

  17. Comparative Kinetic Studies and Performance Evaluation of Biofilm and Biomass Characteristics of Pseudomonas fluorescens in Degrading Synthetic Phenolic Effluent in Inverse Fluidized Bed Biofilm Reactor.

    PubMed

    Begum, S Sabarunisha; Radha, K V

    2016-05-01

    The bioremediation potential of Pseudomonas fluorescens was studied in an Inverse Fluidized Bed Biofilm Reactor under batch recirculation conditions using synthetic phenolic effluent of various concentrations (400, 600, 800, 1000 and 1200 mg/l). The performance of the reactor was investigated and the characteristics of biomass and biofilm were determined by evaluating biofilm dry density and thickness, bioparticle density, suspended and attached biomass concentration, chemical oxygen demand and phenol removal efficiency. Biodegradation kinetics had been studied for suspended biomass culture and biofilm systems with respect to its specific growth and substrate consumption rates. Suspended biomass followed substrate inhibition kinetics and the experimental data fitted well with the Haldane model. The degradation kinetic behavior of biofilm revealed that a well adapted biofilm system with effective control of biofilm thickness in an inverse fluidized bed biofilm reactor overcomes substrate inhibition effects by tolerating higher phenol concentration and fitted well to the Monod model. PMID:27131305

  18. Assessing a bioremediation strategy in a shallow coastal system affected by a fish farm culture--application of GIS and shellfish dynamic models in the Rio San Pedro, SW Spain.

    PubMed

    Silva, C; Yáñez, E; Martín-Díaz, M L; DelValls, T A

    2012-04-01

    An integrated multi-trophic aquaculture assessment for Pacific oyster (Crassostrea gigas) aquaculture as a bioremediation strategy in areas impacted by fish farm effluents in Rio San Pedro was assessed by combining geographic information system with carrying capacity models. Sites of 0.44 km(2) were evaluated considering constraints; physical factors, growth and survival factors, environmental quality factors, water and sediment quality criteria, factor suitability ranges, and Multi-Criteria Evaluation. Isleta and Flamenco are promising sites for oyster production, and Dorada is of marginal interest. Carbon and nitrogen removal from the water by algae and through detritus filtration was estimated. The biodeposition of organic material from longline leases was found to have little negative impact on sediment. The eutrophication results indicate that phytoplankton removal had a positive impact on water quality at the Dorada. This case study quantified the direct profitability and bioremediative environmental service advantages that fish-shellfish farms can have relative to fish monocultures. PMID:22310375

  19. ASSESSMENT OF GENOTOXIC ACTIVITY OF PETROLEUM HYDROCARBON-BIOREMEDIATED SOIL

    SciTech Connect

    BRIGMON, ROBIN

    2004-10-20

    The relationship between toxicity and soil contamination must be understood to develop reliable indicators of environmental restoration for bioremediation. Two bacterial rapid bioassays: SOS chromotest and umu-test with and without metabolic activation (S-9 mixture) were used to evaluate genotoxicity of petroleum hydrocarbon-contaminated soil following bioremediation treatment. The soil was taken from an engineered biopile at the Czor Polish oil refinery. The bioremediation process in the biopile lasted 4 years, and the toxicity measurements were done after this treatment. Carcinogens detected in the soil, polyaromatic hydrocarbons (PAHs), were reduced to low concentrations (2 mg/kg dry wt) by the bioremediation process. Genotoxicity was not observed for soils tested with and without metabolic activation by a liver homogenate (S-9 mixture). However, umu-test was more sensitive than SOS-chromotest in the analysis of petroleum hydrocarbon-bioremediated soil. Analytical results of soil used in the bioassays confirmed that the bioremediation process reduced 81 percent of the petroleum hydrocarbons including PAHs. We conclude that the combined test systems employed in this study are useful tools for the genotoxic examination of remediated petroleum hydrocarbon-contaminated soil.

  20. GRACE BIOREMEDIATION TECHNOLOGIES - DARAMEND™ BIOREMEDIATION TECHNOLOGY. INNOVATIVE TECHNOLOGY EVALUATION REPORT

    EPA Science Inventory

    Grace Dearborn's DARAMEND™ Bioremediation Technology was developed to treat soils/sediment contaminated with organic contaminants using solid-phase organic amendments. The amendments increase the soil’s ability to supply biologically available water/nutrients to micro...

  1. Development of different comprehensive two dimensional systems for the separation of phenolic antioxidants.

    PubMed

    Cacciola, Francesco; Jandera, Pavel; Blahová, Eva; Mondello, Luigi

    2006-11-01

    Three different comprehensive 2-D HPLC systems for the separation of phenolic antioxidants have been developed on the basis of different selectivities of a PEG-silica column in the first dimension and a packed or monolithic C18 or a ZR-CARBON column, respectively, in the second dimension. Two-dimensional comprehensive liquid chromatography using a serially connected short PEG-silica column and a conventional C18-silica or a ZR-CARBON column in the second dimension was tested to improve the resolution of the earlier eluting compounds in the first dimension. Various types of interface were used to connect the columns in the first and in the second dimension: i) two injection sampling loops of 100 microL in conventional arrangement; ii) a 10-port 2-position valve equipped with two trapping X-Terra columns instead of loops; and iii) two analytical D2 columns in parallel. The mobile phase in the first dimension has a lower elution strength than in the second dimension, allowing band compression of the solutes transferred from the first to the second dimension. This effect was enhanced using trapping columns instead of sampling loops as the interface between the two dimensions, thus allowing a decrease in the time of analysis. These systems were used for the analysis of beer samples. The relative location of the components in the 2-D retention plane varied in relation to their chemical structure in each instrumental set-up and allowed positive peak identification. PMID:17154131

  2. Bioremediation of high explosives

    SciTech Connect

    Kitts, C.L.; Alvarez, M.A.; Hanners, J.L.; Ogden, K.L.; Vanderberg-Twary, L.; Unkefer, P.J.

    1995-09-01

    Manufacture and use of high explosives has resulted in contamination of ground water and soils throughout the world. The use of biological methods for remediation of high explosives contamination has received considerable attention in recent years. Biodegradation is most easily studied using organisms in liquid cultures. Thus, the amount of explosive that can be degraded in liquid culture is quite small. However, these experiments are useful for gathering basic information about the biochemical pathways of biodegradation, identifying appropriate organisms and obtaining rates of degradation. The authors` laboratory has investigated all three major areas of explosives bioremediation: explosives in solution, explosives in soil, and the disposal of bulk explosives from demilitarization operations. They investigated the three explosives most commonly used in modern high explosive formulations: 2,4,6-trinitrotoluene (TNT), hexahydro 1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX).

  3. Bioremediation with oleophilic fertilizer

    SciTech Connect

    Basseres, A.; Ladousse, A.

    1993-12-31

    To enhance hydrocarbon breakdown by indigenous microbial communities, a fertilizer formulation that would keep nutrients in contact with oil, was designed ten years ago by ELF AQUITAINE. The fertilizer known as INIPOL EAP 22 is an oil soluble additive but also an easily biodegradable carbon source (oleic acid). Numerous experiments, in both laboratory and field, have shown that the application of this fertilizer increases the number of hydrocarbon degrading organisms and the extent and rate of hydrocarbon biodegradation Laboratory experiments with radiolabelled hydrocarbons have shown that in addition to its physico chemical role, oleic acid acts as a biological starter, increasing the biomass and the rate of biodegradation. A large bioremediation project in ALASKA has shown that it its possible to enhance the biodegradation of oil through the application of such a fertilizer, on coarse sediments. Recently, on sandy sediments, the use of INIPOL EAP 22 shown a clear development in hydrocarbon specific bacteria, and an increase of the rate of biodegradation.

  4. ORD RESEARCH PRIORITIES IN BIOREMEDIATION

    EPA Science Inventory

    ORD is conducting research on bioremediation impacting Superfund sites, RCRA facilities, underground storage tanks and oil spills. Work supporting Superfund is focused on understanding monitored natural recovery in sediments for contaminants including PCBs and PAHs. Under RCRA,...

  5. BIOREMEDIATION OF PETROLEUM HYDROCARBONS: A FLEXIBLE VARIABLE SPEED TECHNOLOGY

    EPA Science Inventory

    The bioremediation of petroleum hydrocarbons has evolved into a number of different processes. These processes include in-situ aquifer bioremediation, bioventing, biosparging, passive bioremediation with oxygen release compounds, and intrinsic bioremediation. Although often viewe...

  6. Enzymatic bioremediation of cashew nut shell liquid contamination.

    PubMed

    Cheriyan, Soly; Abraham, Emilia T

    2010-04-15

    Cashew nut shell liquid (CNSL), a by-product of the cashew kernel industry, is a caustic, viscous, dark liquid. The process is done manually, which leaves stains on the hands of the workers. The aim was to find the utility of enzymes, oxidoreductases and proteases for the bioremediation of CNSL, which contains phenolics, mainly cardanol (60-65%). The results show that peroxidase reduced the color of the CNSL solution by polymerization and precipitation, where as laccase, papain and fungal and bacterial protease degraded the phenolic constituents. The degradation was mainly at the double bonds of the C15 hydrocarbon chain of the cardanol. To improve the enzyme stability, laccase and papain was separately immobilized in alginate-starch beads. Immobilized laccase can degrade 28.6% CNSL within 2 h, where as papain takes longer duration, and at 73 h, the adsorbed phenols on the alginate (45.86%) also got degraded. MALDI-TOF MS revealed that, immobilized laccase-papain beads combination; 1:1 (w/w) degraded 60% of the cardanol and some phenolic compounds having molecular mass of 374, 390 and 407. These beads are active and stable in aqueous media, can be used to prepare a mild, nontoxic, ecofriendly, cost effective hand wash solution for the removal of phenolic stains. PMID:20005628

  7. Investigating the use of phenolic rich fraction of pyrolysis bio-oils as an adhesive system

    NASA Astrophysics Data System (ADS)

    Sahaf, Amir

    Fast pyrolysis allows converting of up to 75 % of biomass into a crude bio-oil, which can be separated into a phenolic rich fraction (PRF) via ethyl acetate extraction while a sugar rich fraction preferentially concentrates in the aqueous phase. Rheological and thermal characterization of heat treated PRF from pyrolysis of Douglas Fir is performed using cone and plate rheology set up, dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC). The results show that this material demonstrates a unique thermoplastic behavior with low Tg and softening point that can be systematically manipulated through changes in thermal history. As these materials are good candidates for development of hot melt adhesives, lap shear tests were also performed using wood stripes to evaluate their mechanical properties as an adhesive. Optimization of properties of the PRF is sought in this study through polymer blending with other bio-degradable thermoplastic poly(epsilon-caprolactone) (PCL) and poly(lactic acid) (PLA). Blends of PRF/PCL and PRF/PLA of different ratios are prepared by solvent casting and melt blending and thermally and thermomechanically characterized for their miscibility and phase behavior. Presence of molecular interactions are furthur investigated using Fourier transform infrared spectoscopy (FTIR). The blends show complete miscibility based on their Tg and melting points and significant improvement in shear strength is observed. Mechanisms leading to changes in properties are described and a physical model is proposed. The blend systems have good potential to be used as a thermoplastic bio degradable adhesives with satisfactoty properies.

  8. Authentication of geographical origin and crop system of grape juices by phenolic compounds and antioxidant activity using chemometrics.

    PubMed

    Granato, Daniel; Koot, Alex; Schnitzler, Egon; van Ruth, Saskia M

    2015-03-01

    The main goal of this work was to propose an authentication model based on the phenolic composition and antioxidant and metal chelating capacities of purple grape juices produced in Brazil and Europe in order to assess their typicality. For this purpose, organic, conventional, and biodynamic grape juices produced in Brazil (n = 65) and in Europe (n = 31) were analyzed and different multivariate class-modeling and classification statistical techniques were employed to differentiate juices based on the geographical origin and crop system. Overall, Brazilian juices, regardless of the crop system adopted, presented higher contents of total phenolic compounds and flavonoids, total monomeric anthocyanins, proanthocyanidins, flavonols, flavanols, cyanidin-3-glucoside, delphinidin-3-glucoside, and malvidin-3,5-glucoside. No differences were observed for trans-resveratrol, malvidin-3-glucoside, and pelargonidin-3-glucoside between countries and among crop systems. A total of 91% of Brazilian and 97% of European juices were adroitly classified using partial least squares discriminant analysis when the producing region was considered (92% efficiency), in which the free-radical scavenging activity toward 2,2-diphenyl-1-picrylhydrazyl, content of total phenolic compounds, gallic acid, and malvidin-3-glucoside were the variables responsible for the classification. Intraregional models based on soft independent modeling of class analogy were able to differentiate organic from conventional Brazilian juices as well as conventional and organic/biodynamic European juices. PMID:25675840

  9. PROTOCOL FOR DETERMINING BIOAVAILABILITY AND BIOKINETICS OF ORGANIC POLLUTANTS IN DISPERSED, COMPACTED AND INTACT SOIL SYSTEMS TO ENHANCE IN SITU BIOREMEDIATION

    EPA Science Inventory

    The development of effective in situ and on-site bioremediation technologies can facilitate the cleanup of chemically-contaminated soil sites. Knowledge of biodegradation kinetics and bioavailability of organic pollutants can facilitate decisions on the efficacy of in situ and o...

  10. Influence of genotype, cultivation system and irrigation regime on antioxidant capacity and selected phenolics of blueberries (Vaccinium corymbosum L.).

    PubMed

    Cardeñosa, Vanessa; Girones-Vilaplana, Amadeo; Muriel, José Luis; Moreno, Diego A; Moreno-Rojas, José M

    2016-07-01

    Demand for and availability of blueberries has increased substantially over recent years, driven in part by their health-promoting properties. Three blueberry varieties ('Rocío', V2, and V3) were grown under two cultivation systems (open-field and plastic tunnels) and subjected to two irrigations regimes (100% and 80% of crop evapotranspiration) in two consecutive years (2011-2012). They were evaluated for their phytochemical composition and antioxidant capacity. Genotype influenced the antioxidant capacity and the content of the three groups of phenolics in the blueberries. The antioxidant activity and total flavonols content increased when the blueberries were grown under open-field conditions. Deficit irrigation conditions led to additional positive effects on their phenolics (delphinidn-3-acetilhexoside content was increased under plastic tunnel with deficit irrigation). In conclusion, the amount of phenolic compounds and the antioxidant capacity of blueberries were not negatively affected by water restriction; Moreover, several changes were recorded due to growing system and genotype. PMID:26920295

  11. In-situ bioremediation of TCE-contaminated groundwater

    SciTech Connect

    Travis, B.J.; Rosenberg, N.D.

    1998-12-31

    This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). A barrier to wider use of in situ bioremediation technology is that results are often variable and difficult to predict. In situ bioremediation has shown some very notable and well publicized successes, but implementation of the technology is complex. An incomplete understanding of the effects of variable site characteristics and the lack of adequate tools to predict and measure success have made the design, control and validation of bioremediation more empirical than desired. The long-term objective of this project is to improve computational tools used to assess and optimize the expected performance of bioremediation at a site. An important component of the approach is the explicit inclusion of uncertainties and their effect on the end result. The authors have extended their biokinetics model to include microbial competition and predation processes. Predator species can feed on the microbial species that degrade contaminants, and the simulation studies show that species interactions must be considered when designing in situ bioremediation systems. In particular, the results for TCE indicate that protozoan grazing could reduce the amount of biodegradation by about 20%. These studies also indicate that the behavior of barrier systems can become complex due to predator grazing.

  12. Impact of present and future regulations on bioremediation.

    PubMed

    Bakst, J S

    1991-07-01

    Innovative treatment technologies are in increasing demand to clean up the nation's existing environmental contamination. There also are mounting pressures for industry to minimize the production or generation of hazardous pollutants. Bioremediation is a viable, cost-effective treatment option for both field remediation and treatment in enclosed systems. The use of innovative treatment technologies is largely regulatory driven. Over the last two decades, at least a dozen Federal environmental statutes have been enacted and hundreds of regulations implemented to control releases of pollutants into the air, water and on land. These statutes not only have created markets for the use of treatment technologies, they also may regulate some aspect of the application of that technology. Regarding bioremediation, four statutes should be reviewed to determine if compliance is necessary before employing microorganisms in the field or in enclosed systems. This paper summarizes the Federal statutes (i.e., the Toxic Substances Control Act (TSCA); the Resource Conservation and Recovery Act (RCRA); the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA); and the Federal Plant Pest Act (FPPA], and regulations that may impact the bioremediation industry; outlines potential markets for bioremediation that are being driven by regulations; and highlights, within the regulatory framework, promising applications for the bioremediation of hazardous wastes. PMID:1367330

  13. Formation of hydrogen peroxide and degradation of phenol in synergistic system of pulsed corona discharge combined with TiO2 photocatalysis.

    PubMed

    Wang, Huijuan; Li, Jie; Quan, Xie; Wu, Yan; Li, Guofeng; Wang, Fangzheng

    2007-03-01

    In the present work, a synergistic system of pulsed corona discharge combined with TiO(2) photocatalysis has been developed to investigate the degradation rate of phenol solutions by varying experimental conditions of gas bubbling varieties (air, O(2), and Ar), solution pH values, and radical scavenger additives. The hydrogen peroxide (H(2)O(2)) concentration, which indicated the amount of hydroxyl radicals (OH) in the reaction system under different conditions of gas bubbling varieties and scavenger species, was also reviewed. The obtained results revealed that degradation efficiency of phenol could be increased by the addition of TiO(2) in pulsed discharge system. The gas of Ar and O(2) bubbled into the reaction system was found to be favorable for phenol degradation and H(2)O(2) formation. Both in air bubbling and in O(2) bubbling reaction system, the higher degradation rate of phenol occurred in the case of acidic solution. The addition of sodium carbonate or n-butanol in the solution displayed a negative effect for phenol removal, while the H(2)O(2) concentration showed different changing trend by adding different radical scavengers. The most effective degradation of the three main intermediates of catechol, 1,4-hydroquinone, and 1,4-benzoquinone formed during phenol decomposition existed in the synergistic system of pulsed corona discharge and TiO(2) photocatalysis bubbled with O(2). PMID:16920259

  14. Immobilizing tyrosinase within chitosan gels: A combination catalyst and sorbent for phenol removal

    SciTech Connect

    Sun, Wei-Qiang; Payne, G.F.

    1995-12-01

    Phenols are common contaminants in chemical process effluents. To remove we developed a two step bioremediation approach in which an these contaminants, we developed a two step bioremediation approach in which an enzymatic reaction was coupled with absorption. In the first step, weakly adsorbable phenols are converted to reactive o-quinones by the enzyme tyrosinase. The quinones are then strongly adsorbed onto the surface of a chitosan sorbent in the second steel. Our results show that this two step approach can selectively and efficiently remove phenols from solution. To reduce this approach into practice, we immobilized the tyrosinase within a chitosan gel yielding a combined catalyst-sorbent film. Using this tyrosinase-containing chitosan gel, phenols (i.e. phenol, cresol and catechol) can be completely removed from solution.

  15. Surfactant-enhanced bioremediation

    SciTech Connect

    Churchill, P.F.; Dudley, R.J.; Churchill, S.A.

    1995-12-31

    This study was undertaken to examine the effect of three structurally related, non-ionic surfactants, Triton X-45, Triton X-100 and Triton X-165, as well as the oleophilic fertilizer, Inipol EAP 22, on the rate of biodegradation of phenanthrene by pure bacterial cultures. Each surfactant dramatically increased the apparent aqueous solubility of phenanthrene. Model studies were conducted to investigate the ability of these surfactants to enhance the rate of transport and uptake of polycyclic aromatic hydrocarbons into bacterial cells, and to assess the impact that increasing the aqueous solubility of hydrocarbons has on their rate of biodegradation. The results indicate that increasing the apparent aqueous solubility of hydrocarbons can lead to enhanced biodegradation rates by two Pseudomonas saccharophila strains. However, the experiments also suggest that some surfactants can inhibit aromatic hydrocarbon biodegradation by certain bacteria. The data also support the hypothesis that surface-active components present in the oleophilic fertilizer formulation, Inipol EAP 22, may have significantly contributed to the positive results reported in tests of remedial agent impact on bioremediation, which was used as a supplemental clean-up technology on Exxon Valdez crude oil-contaminated Alaskan beaches.

  16. Phenol degradation in heterogeneous system generating singlet oxygen employing light activated electropolymerized phenothiazines

    NASA Astrophysics Data System (ADS)

    Piwowar, Katarzyna; Blacha-Grzechnik, Agata; Bernas, Paulina; Zak, Jerzy

    2015-12-01

    Five selected amine-derivatives of phenothiazine were electropolymerized on an ITO/glass substrate and then used in the daylight-activated process to produce in situ singlet oxygen which degrades phenol in a solution. The phenothiazines were immobilized in a simple electrochemical procedure in an acidic solution which led to the formation of an ultrathin transparent polymeric film. All films obtained on the ITO substrate including azure A (AA), azure C (AC), methylene blue (MB), toluidine blue (TBO), and thionine (Th) had a comparable surface coverage at the level of picomoles/cm2. The activity of these materials was then compared and presented in terms of an efficiency of the phenol degradation process in an aqueous solution by photogenerated singlet oxygen. That efficiency was determined by the UV-vis spectroscopy employing a phenol/4-aminoantipyrine complex. All the phenothiazine ultrathin polymeric films were capable of generating the singlet oxygen in the aqueous solution under daylight activation, which was used in the consecutive process of phenol degradation. The highest efficiency at a level of 51.4% and 45.4% was found for the AC/ITO and MB/ITO layers, respectively.

  17. In situ bioremediation of contaminated unsaturated subsurface soils

    SciTech Connect

    Sims, J.L.; Sims, R.C.; Dupont, R.R.; Matthews, J.E.; Russell, H.H.

    1993-05-01

    An emerging technology for the remediation of unsaturated subsurface soils involves the use of microorganisms to degrade contaminants which are present in such soils. Understanding the processes which drive in situ bioremediation, as well as the effectiveness and efficiency of the utilization of these systems, are issues which have been identified by the Regional Superfund Engineering Forum as concerns of Superfund decision makers. Although in situ bioremediation has been used for a number of years in the restoration of ground water contaminated by petroleum hydrocarbons, it has only been in recent years that in situ systems have been directed toward contaminants in unsaturated subsurface soils. Research has contributed greatly to understanding the biotic, chemical, and hydrologic parameters which contribute to or restrict the application of in-situ bioremediation and has been successful at a number of locations in demonstrating its effectiveness at field scale.

  18. Electronic Signatures of a Model Pollutant-Particle System: Chemisorbed Phenol on TiO2(110)

    PubMed Central

    Patterson, Matthew C.; Thibodeaux, Chad A.; Kizilkaya, Orhan; Kurtz, Richard L.; Poliakoff, E. D.; Sprunger, Phillip T.

    2015-01-01

    Environmentally persistent free radicals (EPFRs) are a class of composite organic/metal oxide pollutants that have recently been discovered to form from a wide variety of substituted benzenes chemisorbed to commonly encountered oxides. Although a qualitative understanding of EPFR formation on particulate metal oxides has been achieved, a detailed understanding of the charge transfer mechanism that must accompany the creation of an unpaired radical electron is lacking. In this study, we perform photoelectron spectroscopy and electron energy loss spectroscopy on a well-defined model systemphenol chemisorbed on TiO2(110) – to directly observe changes in the electronic structure of the oxide and chemisorbed phenol as a function of adsorption temperature. We show strong evidence that, upon exposure at high temperature, empty states in the TiO2 are filled and the phenol HOMO is depopulated, as has been proposed in a conceptual model of EPFR formation. This experimental evidence of charge transfer provides a deeper understanding of the EPFR formation mechanism to guide future experimental and computational studies, as well as potential environmental remediation strategies. PMID:25774565

  19. The development and application of engineered proteins for bioremediation

    SciTech Connect

    Trewhella, J.

    1995-09-26

    Clean up of the toxic legacy of the Cold War is projected to be the most expensive domestic project the nation has yet undertaken. Remediation of the Department of Energy and Department of Defense toxic waste sites alone are projected to cost {approximately}$1 trillion over a 20-30 year period. New, cost effective technologies are needed to attack this enormous problem. Los Alamos has put together a cross-divisional team of scientist to develop science based bioremediation technology to work toward this goal. In the team we have expertise in: (1) molecular, ecosystem and transport modeling; (2) genetic and protein engineering; (3) microbiology and microbial ecology; (4) structural biology; and (5) bioinorganic chemistry. This document summarizes talks at a workshop of different aspects of bioremediation technology including the following: Introducing novel function into a Heme enzyme: engineering by excavation; cytochrome P-450: ideal systems for bioremediation?; selection and development of bacterial strains for in situ remediation of cholorinated solvents; genetic analysis and preparation of toluene ortho-monooxygenase for field application in remediation of trichloroethylene; microbial ecology and diversity important to bioremediation; engineering haloalkane dehalogenase for bioremediation; enzymes for oxidative biodegradation; indigenous bacteria as hosts for engineered proteins; performance of indigenous bacterial, hosting engineered proteins in microbial communities.

  20. Pervaporation of phenols

    DOEpatents

    Boddeker, K.W.

    1989-02-21

    Aqueous phenolic solutions are separated by pervaporation to yield a phenol-depleted retentate and a phenol-enriched permeate. The separation effect is enhanced by phase segregation into two immiscible phases, phenol in water'' (approximately 10% phenol), and water in phenol'' (approximately 70% phenol). Membranes capable of enriching phenols by pervaporation include elastomeric polymers and anion exchange membranes, membrane selection and process design being guided by pervaporation performance and chemical stability towards phenolic solutions. Single- and multiple-stage processes are disclosed, both for the enrichment of phenols and for purification of water from phenolic contamination. 8 figs.

  1. Pervaporation of phenols

    DOEpatents

    Boddeker, Karl W.

    1989-01-01

    Aqueous phenolic solutions are separated by pervaporation to yield a phenol-depleted retentate and a phenol-enriched permeate. The separation effect is enhanced by phase segregation into two immiscible phases, "phenol in water" (approximately 10% phenol), and "water in phenol" (approximately 70% phenol). Membranes capable of enriching phenols by pervaporation include elastomeric polymers and anion exchange membranes, membrane selection and process design being guided by pervaporation performance and chemical stability towards phenolic solutions. Single- and multiple-stage procresses are disclosed, both for the enrichment of phenols and for purification of water from phenolic contamination.

  2. Fungal Laccases and Their Applications in Bioremediation

    PubMed Central

    Viswanath, Buddolla; Rajesh, Bandi; Janardhan, Avilala; Kumar, Arthala Praveen; Narasimha, Golla

    2014-01-01

    Laccases are blue multicopper oxidases, which catalyze the monoelectronic oxidation of a broad spectrum of substrates, for example, ortho- and para-diphenols, polyphenols, aminophenols, and aromatic or aliphatic amines, coupled with a full, four-electron reduction of O2 to H2O. Hence, they are capable of degrading lignin and are present abundantly in many white-rot fungi. Laccases decolorize and detoxify the industrial effluents and help in wastewater treatment. They act on both phenolic and nonphenolic lignin-related compounds as well as highly recalcitrant environmental pollutants, and they can be effectively used in paper and pulp industries, textile industries, xenobiotic degradation, and bioremediation and act as biosensors. Recently, laccase has been applied to nanobiotechnology, which is an increasing research field, and catalyzes electron transfer reactions without additional cofactors. Several techniques have been developed for the immobilization of biomolecule such as micropatterning, self-assembled monolayer, and layer-by-layer techniques, which immobilize laccase and preserve their enzymatic activity. In this review, we describe the fungal source of laccases and their application in environment protection. PMID:24959348

  3. In situ bioremediation in Europe

    SciTech Connect

    Porta, A.; Young, J.K.; Molton, P.M.

    1993-06-01

    Site remediation activity in Europe is increasing, even if not at the forced pace of the US. Although there is a better understanding of the benefits of bioremediation than of other approaches, especially about in situ bioremediation of contaminated soils, relatively few projects have been carried out full-scale in Europe or in the US. Some engineering companies and large industrial companies in Europe are investigating bioremediation and biotreatment technologies, in some cases to solve their internal waste problems. Technologies related to the application of microorganisms to the soil, release of nutrients into the soil, and enhancement of microbial decontamination are being tested through various additives such as surfactants, ion exchange resins, limestone, or dolomite. New equipment has been developed for crushing and mixing or injecting and sparging the microorganisms, as have new reactor technologies (e.g., rotating aerator reactors, biometal sludge reactors, and special mobile containers for simultaneous storage, transportation, and biodegradation of contaminated soil). Some work has also been done with immobilized enzymes to support and restore enzymatic activities related to partial or total xenobiotic decontamination. Finally, some major programs funded by public and private institutions confirm that increasing numbers of firms have a working interest in bioremediation.

  4. TESTING BIOREMEDIATION IN THE FIELD

    EPA Science Inventory

    An operational definition for success of in situ bioremediation at field scale includes meeting regulatory goals for ground water quality in a timely fashion at a predictable cost. urrent practice for site characterization does not adequately define the amount of contamination su...

  5. ANAEROBIC BIOREMEDIATION OF CHLORINATED ETHENES

    EPA Science Inventory

    The failure of what have been termed convential methods to reclaim contaminated environmental media has over the years lead to the interest and development of alternative technologies. One of these technologies is bioremediation, or the utilization of microbial agents to reduce ...

  6. Removal of COD, phenols and ammonium from Lurgi coal gasification wastewater using A2O-MBR system.

    PubMed

    Wang, Zixing; Xu, Xiaochen; Gong, Zheng; Yang, Fenglin

    2012-10-15

    As a typical industrial wastewater, coal gasification wastewater has poor biodegradability and high toxicity. In this paper, a laboratory-scale anaerobic-anoxic-oxic membrane reactor (A(2)O-MBR) system was developed to investigate the treatment ability of coal gasification wastewater. The removal capacity of each pollutants used in this system were determined at different hydraulic residence times (HRT) and mixed liquor recycle ratios (R). The experimental results showed that this system could effectively deal with COD and phenol removal and remain in a stable level when the operational parameters altered, while the nitrification was sensitive to operational conditions. The best performance was obtained at HRT of 48 h and R of 3. The maximum removal efficiencies of COD, NH(4)(+)-N and phenols were 97.4%, 92.8% and 99.7%, with final concentrations in the effluent of 71 mg/L, 9.6 mg/L and 3 mg/L, respectively. Organics degradation and transformation were analyzed by GC/MS and it was found that anaerobic process played an important role in degradation of refractory compounds. PMID:22902132

  7. UTILIZATION OF TREATABILITY AND PILOT TESTS TO PREDICT CAH BIOREMEDIATION

    EPA Science Inventory

    Multiple tools have been suggested to help in the design of enhanced anaerobic bioremediation systems for CAHs:
    - Extensive high quality microcosm testing followed by small-scale, thoroughly observed field pilot tests (i.e., RABITT Protocol, Morse 1998)
    - More limited ...

  8. Bioremediation of Petroleum Hydrocarbon-Contaminated Soils, Comprehensive Report

    SciTech Connect

    Altman, D.J.

    2001-01-12

    The US Department of Energy and the Institute for Ecology of Industrial Areas, Katowice, Poland have been cooperating in the development and implementation of innovative environmental remediation technologies since 1995. U.S. experts worked in tandem with counterparts from the IETU and CZOR throughout this project to characterize, assess and subsequently, design, implement and monitor a bioremediation system.

  9. Removal of phenolic compounds in soil

    SciTech Connect

    Nam-Koong, W.

    1988-01-01

    The objective of this research was an evaluation of the removal rates of phenolic compounds in soil. Seventeen phenolic compounds with similar structure were chosen. Relative toxicity of phenolic compounds also was determined by the Microtox{sup TM} System to evaluate the relationship between the toxicity of the phenolic compounds and removal rate. The amount of ATP in the soil was measured by a Lumac/3M biocounter to evaluate any effect of phenolic compounds on the soil microbial activity. Preferential removal of phenolic compounds occurred in mixtures. The presence of phenol and/or o-cresol reduced the removal rate of 2,4-dichlorophenol. Reapplications of the phenolic compounds did not change the removal rate of the compounds. There was good correlation between the relative toxicity of phenolic compounds and zero order removal rates. The less toxic phenolic compounds were removed more rapidly. No lag phase was observed for the removal of phenolic compounds when the compounds were applied to soil below the toxic level. Phenolic compounds had a significant effect on soil microbial activity based on ATP measurement. The increase in soil ATP was related to a rapid removal of phenol. A gradual decrease in soil ATP was observed with the removal of 2,4-dichlorophenol.

  10. Cometabolic degradation kinetics of TCE and phenol by Pseudomonas putida.

    PubMed

    Chen, Yan-Min; Lin, Tsair-Fuh; Huang, Chih; Lin, Jui-Che

    2008-08-01

    Modeling of cometabolic kinetics is important for better understanding of degradation reaction and in situ application of bio-remediation. In this study, a model incorporated cell growth and decay, loss of transformation activity, competitive inhibition between growth substrate and non-growth substrate and self-inhibition of non-growth substrate was proposed to simulate the degradation kinetics of phenol and trichloroethylene (TCE) by Pseudomonas putida. All the intrinsic parameters employed in this study were measured independently, and were then used for predicting the batch experimental data. The model predictions conformed well to the observed data at different phenol and TCE concentrations. At low TCE concentrations (<2 mg l(-1)), the models with or without self-inhibition of non-growth substrate both simulated the experimental data well. However, at higher TCE concentrations (>6 mg l(-1)), only the model considering self-inhibition can describe the experimental data, suggesting that a self-inhibition of TCE was present in the system. The proposed model was also employed in predicting the experimental data conducted in a repeated batch reactor, and good agreements were observed between model predictions and experimental data. The results also indicated that the biomass loss in the degradation of TCE below 2 mg l(-1) can be totally recovered in the absence of TCE for the next cycle, and it could be used for the next batch experiment for the degradation of phenol and TCE. However, for higher concentration of TCE (>6 mg l(-1)), the recovery of biomass may not be as good as that at lower TCE concentrations. PMID:18586301

  11. Manufacturing of bioreactive nanofibers for bioremediation.

    PubMed

    Tong, Ho-Wang; Mutlu, Baris R; Wackett, Lawrence P; Aksan, Alptekin

    2014-08-01

    Recombinant Escherichia coli (E. coli) cells were successfully encapsulated in reactive membranes comprised of electrospun nanofibers that have biocompatible polyvinyl alcohol (PVA)-based cores entrapping the E. coli and silica-based, mechanically sturdy porous shells. The reactive membranes were produced in a continuous fashion using a coaxial electrospinning system coupled to a microfluidic timer that mixed and regulated the reaction time of the silica precursor and the PVA solution streams. A factorial design method was employed to investigate the effects of the three critical design parameters of the system (the flow rate of the core solution, protrusion of the core needle, and the viscosity of the core solution) and to optimize these parameters for reproducibly and continuously producing high-quality core/shell nanofibers. The feasibility of using the reactive membranes manufactured in this fashion for bioremediation of atrazine, a herbicide, was also investigated. The atrazine degradation rate (0.24 µmol/g of E. coli/min) of the encapsulated E. coli cells expressing the atrazine-dechlorinating enzyme AtzA was measured to be relatively close to that measured with the free cells in solution (0.64 µmol/g of E. coli/min). We show here that the low cost, high flexibility, water insolubility, and high degradation efficiency of the bioreactive membranes manufactured with electrospinning makes it feasible for their wide-spread use in industrial scale bioremediation of contaminated waters. PMID:24615064

  12. Sorption determination of phenols and polycyclic aromatic hydrocarbons in a multiphase constructed wetland system by solid phase microextraction.

    PubMed

    Poerschmann, Juergen; Schultze-Nobre, Luciana

    2014-06-01

    Non-degradative sorption of organic pollutants onto plant roots during phytoremediation is an essential retardation mechanism. To determine the extent of the attenuation processes the freely dissolved concentrations of organic solutes must be determined rather than their total concentrations. Thus, the assessment of attenuation caused by sorption onto plant compartments can be biased when using traditional methods. This bias holds especially true in cases of complex multiphase systems characterized by high concentrations of dissolved and suspended organic matter, both of them contributing to a reduction in concentration of the free solutes. A relatively new approach based on solid phase microextraction (SPME) circumvents these obstacles. SPME measures the true freely dissolved concentration of organic solutes without affecting the sorption equilibrium, thus allowing non-biased conclusions about ecotoxicological hazards of organic sorbates. Herein, sorption of phenols (including alkylated phenols) along with polycyclic aromatic hydrocarbons (PAHs) onto roots of Juncus effusus was investigated. Sorption coefficients in the complex system measured with SPME were significantly higher compared to those measured by traditional methods such as phase separation and solvent extraction. A concept based on Hildebrand solubility parameters was applied to interpret and predict sorption onto helophyte roots. The solubility parameter of the root sorbent was calculated as 26.1 (Jcm(-3))(0.5), which is between that of lignin and cellulose/hemicellulose. PMID:24657368

  13. Optimal binary solvent extraction system for phenolic antioxidants from mengkudu (Morinda citrifolia) fruit.

    PubMed

    Thoo, Yin Yin; Ho, Swee Kheng; Abas, Faridah; Lai, Oi Ming; Ho, Chun Wai; Tan, Chin Ping

    2013-01-01

    Antioxidants have been widely used in the food industry to enhance product quality by preventing oxidation of susceptible substances. This work was carried out to maximise the recovery of total phenolic content (TPC), total flavonoid content (TFC), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical-scavenging capacity and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity from Morinda citrifolia fruit via modification of the ethanol concentration, extraction time and extraction temperature at minimal processing cost. The optimised conditions yielded values of 881.57 ± 17.74 mg GAE/100 g DW for TPC, 552.53 ± 34.16 mg CE/100 g DW for TFC, 799.20 ± 2.97 µmol TEAC/100 g DW for ABTS and 2,317.01 ± 18.13 µmol TEAC/100 g DW for DPPH were 75% ethanol, 40 min of time and 57 °C. The four responses did not differ significantly (p > 0.05) from predicted values, indicating that models obtained are suitable to the optimisation of extraction conditions for phenolics from M. citrifolia. The relative amounts of flavonoids were 0.784 ± 0.01 mg quercetin/g of extract and 1.021 ± 0.04 mg rutin/g of extract. On the basis of the results obtained, M. citrifolia extract can be used as a valuable bioactive source of natural antioxidants. PMID:23771061

  14. Proton transfer in the [phenol-NH3]+ system: An experimental and ab initio study

    NASA Astrophysics Data System (ADS)

    Kim, Ho-Tae; Green, Richard J.; Qian, Jun; Anderson, Scott L.

    2000-04-01

    Mass-analyzed threshold ionization (MATI) has been used to prepare phenol cations in selected vibrational states, including the ground state. Reactions of ground state C6H5OH+ with ND3, studied in a guided ion-beam apparatus, are reported, along with related ab initio calculations. This paper focuses on the energetics and product branching in the proton transfer (PT) channel. Based on thermochemistry in the literature, combined with calculations of the intracomplex PT barrier, PT was expected to make up a large fraction of the total reactive scattering. Experimentally, it is found that PT has a small cross section with clear threshold behavior, and the conclusion is that the PT reaction is endoergic by 4.5±1 kcal/mole. Assuming that NH3 has a proton affinity of 204.0 kcal/mole, this results in a proton affinity for phenoxy radical of 208.7 kcal/mole, and a neutral PhO-H bond energy of 91.1 kcal/mole. The results are used to reinterpret previous dissociative photoionization studies of phenol-ammonia complexes.

  15. C3N4-H5PMo10V2O40: a dual-catalysis system for reductant-free aerobic oxidation of benzene to phenol

    PubMed Central

    Long, Zhouyang; Zhou, Yu; Chen, Guojian; Ge, Weilin; Wang, Jun

    2014-01-01

    Hydroxylation of benzene is a widely studied atom economical and environmental benign reaction for producing phenol, aiming to replace the existing three-step cumene process. Aerobic oxidation of benzene with O2 is an ideal and dream process, but benzene and O2 are so inert that current systems either require expensive noble metal catalysts or wasteful sacrificial reducing agents; otherwise, phenol yields are extremely low. Here we report a dual-catalysis non-noble metal system by simultaneously using graphitic carbon nitride (C3N4) and Keggin-type polyoxometalate H5PMo10V2O40 (PMoV2) as catalysts, showing an exceptional activity for reductant-free aerobic oxidation of benzene to phenol. The dual-catalysis mechanism results in an unusual route to create phenol, in which benzene is activated on the melem unit of C3N4 and O2 by the V-O-V structure of PMoV2. This system is simple, highly efficient and thus may lead the one-step production of phenol from benzene to a more practical pathway. PMID:24413448

  16. Microbes safely, effectively bioremediate oil field pits

    SciTech Connect

    Shaw, B. ); Block, C.S. ); Mills, C.H. )

    1995-01-30

    Natural and augmented bioremediation provides a safe, environmental, fast, and effective solution for removing hydrocarbon stains from soil. In 1992, Amoco sponsored a study with six bioremediation companies, which evaluated 14 different techniques. From this study, Amoco continued using Environmental Protection Co.'s (EPC) microbes for bioremediating more than 145 sites near Farmington, NM. EPC's microbes proved effective on various types of hydrocarbon molecules found in petroleum stained soils from heavy crude and paraffin to volatiles such as BTEX (benzene, toluene, ethylbenzene, xylene) compounds. Controlled laboratory tests have shown that these microbes can digest the hydrocarbon molecules with or without free oxygen present. It is believed that this adaptation gives these microbes their resilience. The paper describes the bioremediation process, environmental advantages, in situ and ex situ bioremediation, goals of bioremediation, temperature effects, time, cost, and example sites that were treated.

  17. Biodegradation of phenolic compounds and their metabolites in contaminated groundwater using microbial fuel cells.

    PubMed

    Hedbavna, Petra; Rolfe, Stephen A; Huang, Wei E; Thornton, Steven F

    2016-01-01

    This is the first study demonstrating the biodegradation of phenolic compounds and their organic metabolites in contaminated groundwater using bioelectrochemical systems (BESs). The phenols were biodegraded anaerobically via 4-hydroxybenzoic acid and 4-hydroxy-3-methylbenzoic acid, which were retained by electromigration in the anode chamber. Oxygen, nitrate, iron(III), sulfate and the electrode were electron acceptors for biodegradation. Electro-active bacteria attached to the anode, producing electricity (~1.8mW/m(2)), while utilizing acetate as an electron donor. Electricity generation started concurrently with iron reduction; the anode was an electron acceptor as thermodynamically favorable as iron(III). Acetate removal was enhanced by 40% in the presence of the anode. However, enhanced removal of phenols occurred only for a short time. Field-scale application of BESs for in situ bioremediation requires an understanding of the regulation and kinetics of biodegradation pathways of the parent compounds to relevant metabolites, and the syntrophic interactions and carbon flow in the microbial community. PMID:26512868

  18. Multivariable optimization of the micellar system for the ionic liquid-modified MEKC separation of phenolic acids.

    PubMed

    Liu, Lei; Wu, Bin; Liu, Ke; Li, Chao-Ran; Zhou, Xu; Li, Ping; Yang, Hua

    2016-07-15

    An ionic liquid (IL)-modified micellar electrokinetic chromatography (MEKC) method was proposed for the separation and determination of eight phenolic acids. In order to increase separation efficiency and selectivity, the micelle system consisting of aqueous mixtures of ILs, Tween 20 and borate was optimized using a D-optimal design. A 16-run experimental plan was carried out. The results indicated that the addition of ILs in background electrolyte could significantly alter the electrophoretic behavior and improve the resolution of target analytes. By evaluating the electropherograms obtained, a satisfactory separation condition for all analytes was achieved in 10min with optimized buffer composed of 0.70% (w/w) 1-butyl-3-methylimidazolium tetrafluoroborate, 8.1% (w/w) polyoxyethylene sorbitan monolaurate (Tween 20) and 10mM sodium borate at pH 9.2. Under these conditions, all calibration curves showed good linearity (r(2)>0.9969), and accuracy (recoveries ranging from 94.71 to 106.85%). Finally, the proposed method was successfully applied to determine the phenolic acids in a Chinese medicine compound, compound danshen dripping pills. PMID:27136281

  19. Oscillatory dynamics of the biologically active zone in in situ bioremediation

    NASA Astrophysics Data System (ADS)

    Murray, Regan E.; Luce, Benjamin P.

    2002-10-01

    In situ bioremediation is a promising biotechnology for removing aqueous phase contaminants from groundwater. The system of three partial differential equations used to model bioremediation has a traveling wave solution which loses stability in a Hopf bifurcation, giving rise to oscillating fronts. To understand the origin of these oscillations, we construct a simplified model of the biologically active zone, a time delay differential equation with state-dependent delay. Despite its simplicity the new model mimics the dynamical characteristics of the bioremediation equations remarkably well and yields an approximate parametric expression for the oscillation onset point.

  20. In situ vadose zone bioremediation.

    PubMed

    Höhener, Patrick; Ponsin, Violaine

    2014-06-01

    Contamination of the vadose zone with various pollutants is a world-wide problem, and often technical or economic constraints impose remediation without excavation. In situ bioremediation in the vadose zone by bioventing has become a standard remediation technology for light spilled petroleum products. In this review, focus is given on new in situ bioremediation strategies in the vadose zone targeting a variety of other pollutants such as perchlorate, nitrate, uranium, chromium, halogenated solvents, explosives and pesticides. The techniques for biostimulation of either oxidative or reductive degradation pathways are presented, and biotransformations to immobile pollutants are discussed in cases of non-degradable pollutants. Furthermore, research on natural attenuation in the vadose zone is presented. PMID:24863890

  1. Spectroscopic Studies on the Interaction of Metallic Ions with an Imidazolyl-Phenolic System.

    PubMed

    Orfão, Ronaldo Barros; Alves, Jessica; Bartoloni, Fernando Heering

    2016-07-01

    A fluorescent imidazolyl-phenolic compound was applied on the detection of metallic species (Cu(2+), Al(3+), Cr(3+) and Fe(3+)) in a CH3CN/H2O (95/5, v/v) media. The presence and concentration of these cations altered significantly the emission profile of the probe, mainly lowering the signal intensity at 466 nm, while a new emission band around 395 nm appeared (for the trivalent ions). These results were rationalized as a combination of collisional quenching (KSV in the 10(3)-10(4) L mol(-1) range) and formation of a coordinated compound. The later disrupts the Excited State Intramolecular Proton Transfer that regulates the keto-enol tautomerism originally present on the free probe. Since the quenching efficiency and the obtained emission profiles are drastically different for Cu(2+) and Fe(3+) ions, this allows their differential recognition. PMID:27210796

  2. Ecogenomics of microbial communities in bioremediation of chlorinated contaminated sites

    PubMed Central

    Maphosa, Farai; Lieten, Shakti H.; Dinkla, Inez; Stams, Alfons J.; Smidt, Hauke; Fennell, Donna E.

    2012-01-01

    Organohalide compounds such as chloroethenes, chloroethanes, and polychlorinated benzenes are among the most significant pollutants in the world. These compounds are often found in contamination plumes with other pollutants such as solvents, pesticides, and petroleum derivatives. Microbial bioremediation of contaminated sites, has become commonplace whereby key processes involved in bioremediation include anaerobic degradation and transformation of these organohalides by organohalide respiring bacteria and also via hydrolytic, oxygenic, and reductive mechanisms by aerobic bacteria. Microbial ecogenomics has enabled us to not only study the microbiology involved in these complex processes but also develop tools to better monitor and assess these sites during bioremediation. Microbial ecogenomics have capitalized on recent advances in high-throughput and -output genomics technologies in combination with microbial physiology studies to address these complex bioremediation problems at a system level. Advances in environmental metagenomics, transcriptomics, and proteomics have provided insights into key genes and their regulation in the environment. They have also given us clues into microbial community structures, dynamics, and functions at contaminated sites. These techniques have not only aided us in understanding the lifestyles of common organohalide respirers, for example Dehalococcoides, Dehalobacter, and Desulfitobacterium, but also provided insights into novel and yet uncultured microorganisms found in organohalide respiring consortia. In this paper, we look at how ecogenomic studies have aided us to understand the microbial structures and functions in response to environmental stimuli such as the presence of chlorinated pollutants. PMID:23060869

  3. Relationship between wood color parameters measured by the CIELab system and extractive and phenol content in Acacia mangium and Vochysia guatemalensis from fast-growth plantations.

    PubMed

    Moya, Róger; Soto Fallas, Roy; Jiménez Bonilla, Pablo; Tenorio, Carolina

    2012-01-01

    The heterogeneity of color distribution between sapwood and heartwood limits the market for wood from fast-growth plantations of tropical species. Wood color is associated with wood extractives contents. This study presents the relationship between wood color parameters measured by the CIELab color system and total amount of extractives and phenolic-type extractives in ethanol-toluene and hot water extracts of wood from two fast-growth plantation species. The results demonstrated that the difference in sapwood and hardwood color in Vochysia guatemalensis and Acacia mangium is caused by lower concentrations of extractives in sapwood of both species. Additionally, variations in total extractive and phenolic content have different effects on the color parameters (L*, a* and b*) of both species studied. In Vochysia guatemalensis wood, parameter L* decreases as total extractive and phenolic content increases; however, parameter a* increases as the content of extractives and phenols increases. In Acacia mangium, the amount of phenols showed no relationship with the color parameters. The ethanol-toluene total extractive content, however, shows a relationship with several color parameters. An increase in the content of total extractives in water and ethanol-toluene increases parameter a*, but decreases parameter L*. PMID:22450677

  4. Influence of phenolic acids on indole acetic acid production and on the type III secretion system gene transcription in food-associated Pseudomonas fluorescens KM05.

    PubMed

    Myszka, Kamila; Schmidt, Marcin T; Olejnik-Schmidt, Agnieszka K; Leja, Katarzyna; Czaczyk, Katarzyna

    2014-12-01

    The purpose of these investigations was to evaluate the reduction capability of phenolic acids (ferulic, chlorogenic, gallic, and p-coumaric acids) on indole acetic acid synthesis by food-associated Pseudomonas fluorescens KM05. Specific genetic primer for the type III secretion system (TTSS) in P. fluorescens KM05 was designed and the influence of phenolic acids on its expression was investigated. In the work the ferulic and chlorogenic acids at the concentration of 0.02 and 0.04 μg/ml affected on bacterial growth pattern and the signal molecules production. The phenolic acids, that were appreciable effective against P. fluorescens KM05 indole acetic acid production, significantly suppressed TTSS gene. PMID:24994472

  5. Phenol Analysis -- Some Analytical Considerations

    NASA Technical Reports Server (NTRS)

    Starkey, R. J., Jr.

    1971-01-01

    Contamination of potable water supplies with halogenated phenols in concentrations of 2-10 parts per billion (ppb) produces objectionable tastes and odors capable of influencing consumer acceptability. Routine analysis by the distillation/ 4-aminoantipyrine method is limited by lack of sensitivity and subject to interference by aryl amines. This has been overcome by developing a continuous liquid-liquid extraction system to selectively isolate phenols and eliminate major interfering substances. Stable reagents have been formulated to reduce blank color and extend sensitivity. Equipment suitable for analysis of phenols at the 1 ppb level or less in 20 minutes is described.

  6. RELATIONSHIPS OF QUANTITATIVE STRUCTURE-ACTIVITY TO COMPARATIVE TOXICITY OF SELECTED PHENOLS IN THE 'PIMEPHALES PROMELAS' AND 'TETRAHYMENA PYRIFORMIS' TEST SYSTEMS

    EPA Science Inventory

    The relative toxic response of 27 selected phenols in the 96-hr acute flowthrough Pimephales promelas (fathead minnow) and the 48- to 60-hr chronic static Tetrahymena pyriformis (ciliate protozoan) test systems was evaluated. Log Kow-dependent linear regression analyses revealed ...

  7. COMPARATIVE IN VITRO PERCUTANEOUS ABSORPTION OF P-SUBSTITUTED PHENOLS THROUGH RAT SKIN USING STATIC AND FLOW-THROUGH DIFFUSION SYSTEMS

    EPA Science Inventory

    The objective of this study was to determine the in vitro percutaneous absorption of [14C]-phenol and eight p-substituted derivatives and to examine the variability of this data. wo diffusion systems, the static and flow-through, were used. lipped dorsal skin was removed from fem...

  8. BIOREMEDIATION OF OIL-CONTAMINATED FINE SEDIMENTS.

    EPA Science Inventory

    Bioremediation of oil contamination has been shown to be effective for cobble and sandy shorelines. To assess the operational limitations of this technology, this project studied its potential to treat buried oil in fine sediments. The effectiveness of bioremediation by nutrient ...

  9. 7 CFR 3201.63 - Bioremediation materials.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Bioremediation materials. 3201.63 Section 3201.63... Designated Items § 3201.63 Bioremediation materials. (a) Definition. Dry or liquid solutions (including those containing bacteria or other microbes but not including sorbent materials) used to clean oil, fuel, and...

  10. Intrinsic bioremediation of landfills interim report

    SciTech Connect

    Brigmon, R.L.; Fliermans, C.B.

    1997-07-14

    Intrinsic bioremediation is a risk management option that relies on natural biological and physical processes to contain the spread of contamination from a source. Evidence is presented in this report that intrinsic bioremediation is occurring at the Sanitary Landfill is fundamental to support incorportion into a Corrective Action Plan (CAP).

  11. Phenolic Impregnated Carbon Ablators (PICA) as Thermal Protection Systems for Discovery Missions

    NASA Technical Reports Server (NTRS)

    Tran, Huy K.; Johnson, Christine E.; Rasky, Daniel J.; Hui, Frank C. L.; Hsu, Ming-Ta; Chen, Timothy; Chen, Y. K.; Paragas, Daniel; Kobayashi, Loreen

    1997-01-01

    This paper presents the development of the light weight Phenolic Impregnated Carbon Ablators (PICA) and its thermal performance in a simulated heating environment for planetary entry vehicles. The PICA material was developed as a member of the Light Weight Ceramic Ablators (LCA's), and the manufacturing process of this material has since been significantly improved. The density of PICA material ranges from 14 to 20 lbm/ft(exp 3), having uniform resin distribution with and without a densified top surface. The thermal performance of PICA was evaluated in the Ames arc-jet facility at cold wall heat fluxes from 375 to 2,960 BtU/ft(exp 2)-s and surface pressures of 0.1 to 0.43 atm. Heat loads used in these tests varied from 5,500 to 29,600 BtU/ft(exp 2) and are representative of the entry conditions of the proposed Discovery Class Missions. Surface and in-depth temperatures were measured using optical pyrometers and thermocouples. Surface recession was also measured by using a template and a height gage. The ablation characteristics and efficiency of PICA are quantified by using the effective heat of ablation, and the thermal penetration response is evaluated from the thermal soak data. In addition, a comparison of thermal performance of standard and surface densified PICA is also discussed.

  12. White rot fungus bioremediation: Mother Nature`s Pollution Solution{reg_sign}

    SciTech Connect

    Keene, M.A.

    1996-12-01

    The white rot fungi (WRF) bioremediation system developed by Intech One-Eight Corp. (INTECH), which has evolved from both the decade of basic research work cited here and additional applied research efforts, may be easily and sharply differentiated from conventional bioremediation processes relying on the enzymatic activities of bacteria. The technology is an on-site, ex situ bioremediation process employing selected strains of WRF to degrade a wide spectrum of environmentally persistent organic compounds which may contaminate soils, sludges and sediments. Successful demonstrations of cost-effective soil decontamination using WRF technology, ranging in size up to 10,000 tons, have now been performed by licensed affiliates. The use of any WRF organisms or their enzymes for the bioremediation of most organic compounds is covered worldwide by issued and pending patents.

  13. Application of immobilized and granular dried anaerobic biomass for stabilizing and increasing anaerobic bio-systems tolerance for high organic loads and phenol shocks.

    PubMed

    Massalha, Nedal; Brenner, Asher; Sheindorf, Chaim; Sabbah, Isam

    2015-12-01

    This study focuses on the stability and tolerance of continuous-flow bioreactors inoculated with anaerobic methanogens in three different configurations: (R1) dried granular biomass immobilized in PAC-enriched hydrophilic polyurethane foam, (R2) dried granular biomass, and (R3) wet granular biomass. These systems were tested under two different organic loading rates (OLR) of 6.25 and 10.94 (gCOD/(Lreactor∗d)), using a glucose-based synthetic mixture. The effect of an instantaneous shock load of phenol (5g/L for three days), and of phenol inclusion in the feed (0.5g/L) were also tested. At the lower OLR, all reactors performed similarly, however, increasing the OLR lead to a significant biomass washout and failure of R3. Biomass in R1 was more tolerant to phenol shock load than R2, though activity was recovered in both systems after about one month. PAC provided protection and shortened the adaptation time for 0.5g/L phenol that continuously was fed. PMID:26318929

  14. Monitoring and interpreting bioremediation effectiveness

    SciTech Connect

    Bragg, J.R.; Prince, R.C.; Harner, J.; Atlas, R.M.

    1993-12-31

    Following the Exxon Valdez oil spill in 1989, extensive research was conducted by the US Environments Protection Agency and Exxon to develop and implement bioremediation techniques for oil spill cleanup. A key challenge of this program was to develop effective methods for monitoring and interpreting bioremediation effectiveness on extremely heterogenous intertidal shorelines. Fertilizers were applied to shorelines at concentrations known to be safe, and effectiveness achieved in acceleration biodegradation of oil residues was measure using several techniques. This paper describes the most definitive method identified, which monitors biodegradation loss by measuring changes in ratios of hydrocarbons to hopane, a cycloalkane present in the oil that showed no measurable degradation. Rates of loss measured by the hopane ratio method have high levels of statistical confidence, and show that the fertilizer addition stimulated biodegradation rates as much a fivefold. Multiple regression analyses of data show that fertilizer addition of nitrogen in interstitial pore water per unit of oil load was the most important parameter affecting biodegradation rate, and results suggest that monitoring nitrogen concentrations in the subsurface pore water is preferred technique for determining fertilizer dosage and reapplication frequency.

  15. Salt-tolerant phenol-degrading microorganisms isolated from Amazonian soil samples.

    PubMed

    Bastos, A E; Moon, D H; Rossi, A; Trevors, J T; Tsai, S M

    2000-11-01

    Two phenol-degrading microorganisms were isolated from Amazonian rain forest soil samples after enrichment in the presence of phenol and a high salt concentration. The yeast Candida tropicalis and the bacterium Alcaligenes faecoalis were identified using several techniques, including staining, morphological observation and biochemical tests, fatty acid profiles and 16S/18S rRNA sequencing. Both isolates, A. faecalis and C. tropicalis, were used in phenol degradation assays, with Rhodococcus erythropolis as a reference phenol-degrading bacterium, and compared to microbial populations from wastewater samples collected from phenol-contaminated environments. C. tropicalis tolerated higher concentrations of phenol and salt (16 mM and 15%, respectively) than A. faecalis (12 mM and 5.6%). The yeast also tolerated a wider pH range (3-9) during phenol degradation than A. faecalis (pH 7-9). Phenol degradation was repressed in C. tropicalis by acetate and glucose, but not by lactate. Glucose and acetate had little effect, while lactate stimulated phenol degradation in A. faecalis. To our knowledge, these soils had never been contaminated with man-made phenolic compounds and this is the first report of phenol-degrading microorganisms from Amazonian forest soil samples. The results support the idea that natural uncontaminated environments contain sufficient genetic diversity to make them valid choices for the isolation of microorganisms useful in bioremediation. PMID:11131025

  16. The plant phenolic compound p-coumaric acid represses gene expression in the Dickeya dadantii type III secretion system.

    PubMed

    Li, Yan; Peng, Quan; Selimi, Dija; Wang, Qi; Charkowski, Amy O; Chen, Xin; Yang, Ching-Hong

    2009-03-01

    The type III secretion system (T3SS) is a major virulence factor in many gram-negative bacterial pathogens. This secretion system translocates effectors directly into the cytosol of eukaryotic host cells, where the effector proteins facilitate bacterial pathogenesis by interfering with host cell signal transduction and other cellular processes. Plants defend themselves against bacterial pathogens by recognizing either the type 3 effectors or their actions and initiating a cascade of defense responses that often results in programmed cell death of the plant cell being attacked. Here we show that a plant phenolic compound, p-coumaric acid (PCA), represses the expression of T3SS genes of the plant pathogen Dickeya dadantii, suggesting that plants can also defend against bacterial pathogens by manipulating the expression of the T3SS. PCA repressed the expression of T3SS regulatory genes through the HrpX/Y two-component system, a core regulator of the T3SS, rather than through the global regulator GacS/A, which indirectly regulates the T3SS. A further analysis of several PCA analogs suggests that the para positioning of the hydroxyl group in the phenyl ring and the double bond of PCA may be important for its biological activity. PMID:19114532

  17. Potential of Penicillium Species in the Bioremediation Field

    PubMed Central

    Leitão, Ana Lúcia

    2009-01-01

    The effects on the environment of pollution, particularly that caused by various industrial activities, have been responsible for the accelerated fluxes of organic and inorganic matter in the ecosphere. Xenobiotics such as phenol, phenolic compounds, polycyclic aromatic hydrocarbons (PAHs), and heavy metals, even at low concentrations, can be toxic to humans and other forms of life. Many of the remediation technologies currently being used for contaminated soil and water involve not only physical and chemical treatment, but also biological processes, where microbial activity is the responsible for pollutant removal and/or recovery. Fungi are present in aquatic sediments, terrestrial habitats and water surfaces and play a significant part in natural remediation of metal and aromatic compounds. Fungi also have advantages over bacteria since fungal hyphae can penetrate contaminated soil, reaching not only heavy metals but also xenobiotic compounds. Despite of the abundance of such fungi in wastes, penicillia in particular have received little attention in bioremediation and biodegradation studies. Additionally, several studies conducted with different strains of imperfecti fungi, Penicillium spp. have demonstrated their ability to degrade different xenobiotic compounds with low co-substrate requirements, and could be potentially interesting for the development of economically feasible processes for pollutant transformation. PMID:19440525

  18. Bioremediation of petroleum hydrocarbon-contaminated ground water: The perspectives of history and hydrology

    USGS Publications Warehouse

    Chapelle, F.H.

    1999-01-01

    Bioremediation, the use of microbial degradation processes to detoxify environmental contamination, was first applied to petroleum hydrocarbon-contaminated ground water systems in the early 1970s. Since that time, these technologies have evolved in some ways that were clearly anticipated early investigators, and in other ways that were not foreseen. The expectation that adding oxidants and nutrients to contaminated aquifers would enhance biodegradation, for example, has been born out subsequent experience. Many of the technologies now in common use such as air sparging, hydrogen peroxide addition, nitrate addition, and bioslurping, are conceptually similar to the first bioremediation systems put into operation. More unexpected, however, were the considerable technical problems associated with delivering oxidants and nutrients to heterogeneous ground water systems. Experience has shown that the success of engineered bioremediation systems depends largely on how effectively directions and rates of ground water flow can be controlled, and thus how efficiently oxidants and nutrients can be delivered to contaminated aquifer sediments. The early expectation that injecting laboratory-selected or genetically engineered cultures of hydrocarbon-degrading bacteria into aquifers would be a useful bioremediation technology has not been born out subsequent experience. Rather, it appears that petroleum hydrocarbon-degrading bacteria are ubiquitous in ground water systems and that bacterial addition is usually unnecessary. Perhaps the technology that was least anticipated early investigators was the development of intrinsic bioremediation. Experience has shown that natural attenuation mechanisms - biodegradation, dilution, and sorption - limit the migration of contaminants to some degree in all ground water systems. Intrinsic bioremediation is the deliberate use of natural attenuation processes to treat contaminated ground water to specified concentration levels at predetermined

  19. O-Allylation of phenols with allylic acetates in aqueous media using a magnetically separable catalytic system

    EPA Science Inventory

    Allylic ethers were synthesized in water using magnetically recoverable heterogeneous Pd catalyst via O-allylation of phenols with allylic acetates under ambient conditions. Aqueous reaction medium, easy recovery of the catalyst using an external magnet, efficient recycling, and ...

  20. Modelling and simulation of photocatalytic oxidation mechanism of chlorohalogenated substituted phenols in batch systems: Langmuir-Hinshelwood approach.

    PubMed

    Khuzwayo, Z; Chirwa, E M N

    2015-12-30

    This study investigated, modelled and simulated the influence of multi-chlorohalogenation in heterogeneous photocatalytic degradation of substituted phenols (pentachlorophenol (PCP), trichlorophenol (TCP), dichlorophenol (DCP), and monochlorophenol (CP)). The Langmuir-Hinshelwood approach was applied to determine oxidation kinetics. Aquasim 2.0 computational software was used to model, simulate and estimate model parameters of the different chlorophenols. Chemical adsorption equilibrium isotherms for the four chlorophenols and phenol were studied and modelled for adsorption onto titanium dioxide (TiO2) semiconductor catalyst. Langmuir adsorption parameters were determined and used to calculate adsorption constant and maximum adsorption capacity. The adsorption of chloride phenolics onto titanium dioxide catalyst increased in the order of 4 - CP < DCP < Ph < TCP < PCP. Photocatalytic studies analysed the efficiency of oxidation and found improved degradation with higher chloride substituted phenolics in the order of PCP > TCP > DCP ≥ 4 - CP. Photocatalytic parameters were calculated and estimated along with sensitivity and uncertainty analyses. PMID:26223020

  1. Bioremediation of metals and inorganic compounds

    SciTech Connect

    Alleman, B.C.; Leeson, A.

    1999-11-01

    Bioremediation has been a problematic alternative for remediation of metals and inorganic compound contamination. Unlike organic contaminants, which often can be broken down by biological processes into relatively harmless metabolites and byproducts, metals are elemental. Further, metals and their salts often have an inhibitory effect on biological activity. However, despite these potential pitfalls, there has been progress recently in applying bioremediation technologies to metals and inorganics. This volume encompasses topics such as lead solubility reduction, chromium reduction, denitrification, volatilization of selenium in soils, metals recovery from acid mine drainage, and even the possibility of applying artificial neural network technology to aid in bioremediation.

  2. Bioremediation of nitrates and carbon tetrachloride in groundwater

    SciTech Connect

    Brouns, T.M.

    1993-01-01

    A development and demonstration program is presently underway to test an in situ bioremediation technology for treating nitrates and carbon tetrachloride in contaminated Hanford groundwaters. Several key technical issues have prevented widespread use of bioremediation for cleanup of organic and inorganic subsurface contaminants, including the development of adequate nutrient delivery systems; effective mixing technologies for contacting microorganisms, nutrients, and contaminants; methods to control biofouling or excessive microbial growth; and adequate tools for designing, predicting, and monitoring the performance of in situ technologies in heterogeneous subsurface environments. The goal of this program is to address these technical issues in an integrated laboratory-, bench-, and field-scale demonstration by stimulating native microorganisms and accelerating the natural degradation of NO{sub 3}{sup {minus}} CCl{sub 4} and chloroform.

  3. Bioremediation of nitrates and carbon tetrachloride in groundwater

    SciTech Connect

    Brouns, T.M.

    1993-01-01

    A development and demonstration program is presently underway to test an in situ bioremediation technology for treating nitrates and carbon tetrachloride in contaminated Hanford groundwaters. Several key technical issues have prevented widespread use of bioremediation for cleanup of organic and inorganic subsurface contaminants, including the development of adequate nutrient delivery systems; effective mixing technologies for contacting microorganisms, nutrients, and contaminants; methods to control biofouling or excessive microbial growth; and adequate tools for designing, predicting, and monitoring the performance of in situ technologies in heterogeneous subsurface environments. The goal of this program is to address these technical issues in an integrated laboratory-, bench-, and field-scale demonstration by stimulating native microorganisms and accelerating the natural degradation of NO[sub 3][sup [minus

  4. Phenolic acids inhibit the formation of advanced glycation end products in food simulation systems depending on their reducing powers and structures.

    PubMed

    Chen, Hengye; Virk, Muhammad Safiullah; Chen, Fusheng

    2016-06-01

    The concentration of advanced glycation end products (AGEs) in foods, which are formed by Maillard reaction, has demonstrated as risk factors associated with many chronic diseases. The AGEs inhibitory activities of five common phenolic acids (protocatechuic acid, dihydroferulic acid, p-coumaric acid, p-hydroxybenzoic acid and salicylic acid) with different chemical properties had been investigated in two food simulation systems (glucose-bovine serum albumin (BSA) and oleic acid-BSA). The results substantiated that the AGEs inhibitory abilities of phenolic acids in the oleic acid BSA system were much better than the glucose-BSA system for their strong reducing powers and structures. Among them, dihydrogenferulic acid showed strong inhibition of AGEs formation in oleic acid-BSA system at 0.01 mg/mL compared to nonsignificant AGEs inhibitory effect in oleic acid-BSA system at 10-fold higher concentration (0.1 mg/mL). This study suggests that edible plants rich in phenolic acids may be used as AGEs inhibitor during high-fat cooking. PMID:27102241

  5. Biosurfactant-enhanced soil bioremediation

    SciTech Connect

    Kosaric, N.; Lu, G.; Velikonja, J.

    1995-12-01

    Bioremediation of soil contaminated with organic chemicals is a viable alternative method for clean-up and remedy of hazardous waste sites. The final objective in this approach is to convert the parent toxicant into a readily biodegradable product which is harmless to human health and/or the environment. Biodegradation of hydrocarbons in soil can also efficiently be enhanced by addition or in-situ production of biosufactants. It was generally observed that the degradation time was shortened and particularly the adaptation time for the microbes. More data from our laboratories showed that chlorinated aromatic compounds, such as 2,4-dichlorophenol, a herbicide Metolachlor, as well as naphthalene are degraded faster and more completely when selected biosurfactants are added to the soil. More recent data demonstrated an enhanced biodegradation of heavy hydrocarbons in petrochemical sludges, and in contaminated oil when biosurfactants were present or were added prior to the biodegradation process.

  6. Treatment of a mud pit by bioremediation.

    PubMed

    Avdalović, Jelena; Đurić, Aleksandra; Miletić, Srdjan; Ilić, Mila; Milić, Jelena; Vrvić, Miroslav M

    2016-08-01

    The mud generated from oil and natural gas drilling, presents a considerable ecological problem. There are still insufficient remedies for the removal and minimization of these very stable emulsions. Existing technologies that are in use, more or less successfully, treat about 20% of generated waste drilling mud, while the rest is temporarily deposited in so-called mud pits. This study investigated in situ bioremediation of a mud pit. The bioremediation technology used in this case was based on the use of naturally occurring microorganisms, isolated from the contaminated site, which were capable of using the contaminating substances as nutrients. The bioremediation was stimulated through repeated inoculation with a zymogenous microbial consortium, along with mixing, watering and biostimulation. Application of these bioremediation techniques reduced the concentration of total petroleum hydrocarbons from 32.2 to 1.5 g kg(-1) (95% degradation) during six months of treatment. PMID:27354013

  7. BIOREMEDIATED SOIL VENTING OF LIGHT HYDROCARBONS

    EPA Science Inventory

    The effectiveness and feasibility of bioremediated soil venting of light hydrocarbons in the unsaturated zone was investigated. Degradation mechanics were considered as a one dimensional balance of storage, linear sorption, vertical advection, and Michaelis-Menton kinetics. he re...

  8. Derivatives of Plant Phenolic Compound Affect the Type III Secretion System of Pseudomonas aeruginosa via a GacS-GacA Two-Component Signal Transduction System

    PubMed Central

    Yamazaki, Akihiro; Li, Jin; Zeng, Quan; Khokhani, Devanshi; Hutchins, William C.; Yost, Angela C.; Biddle, Eulandria; Toone, Eric J.

    2012-01-01

    Antibiotic therapy is the most commonly used strategy to control pathogenic infections; however, it has contributed to the generation of antibiotic-resistant bacteria. To circumvent this emerging problem, we are searching for compounds that target bacterial virulence factors rather than their viability. Pseudomonas aeruginosa, an opportunistic human pathogen, possesses a type III secretion system (T3SS) as one of the major virulence factors by which it secretes and translocates T3 effector proteins into human host cells. The fact that this human pathogen also is able to infect several plant species led us to screen a library of phenolic compounds involved in plant defense signaling and their derivatives for novel T3 inhibitors. Promoter activity screening of exoS, which encodes a T3-secreted toxin, identified two T3 inhibitors and two T3 inducers of P. aeruginosa PAO1. These compounds alter exoS transcription by affecting the expression levels of the regulatory small RNAs RsmY and RsmZ. These two small RNAs are known to control the activity of carbon storage regulator RsmA, which is responsible for the regulation of the key T3SS regulator ExsA. As RsmY and RsmZ are the only targets directly regulated by GacA, our results suggest that these phenolic compounds affect the expression of exoS through the GacSA-RsmYZ-RsmA-ExsA regulatory pathway. PMID:21968370

  9. Numerical simulation of in situ bioremediation

    SciTech Connect

    Travis, B.J.

    1998-12-31

    Models that couple subsurface flow and transport with microbial processes are an important tool for assessing the effectiveness of bioremediation in field applications. A numerical algorithm is described that differs from previous in situ bioremediation models in that it includes: both vadose and groundwater zones, unsteady air and water flow, limited nutrients and airborne nutrients, toxicity, cometabolic kinetics, kinetic sorption, subgridscale averaging, pore clogging and protozoan grazing.

  10. EFFECTIVENESS AND SAFETY OF STRATEGIES FOR OIL SPILL BIOREMEDIATION: POTENTIAL AND LIMITATION, LABORATORY TO FIELD (RESEARCH BRIEF)

    EPA Science Inventory

    Several important additional research efforts were identified during the development of test systems and protocols for assessing the effectiveness and environmental safety of oil spill commercial bioremediation agents (CBAs). Research that examined CBA efficacy issues included: (...

  11. Treatment of coal gasification wastewater by a two-continuous UASB system with step-feed for COD and phenols removal.

    PubMed

    Wang, Wei; Han, Hongjun; Yuan, Min; Li, Huiqiang; Fang, Fang; Wang, Ke

    2011-05-01

    A two-continuous mesophilic (37 ± 2°C) UASB system with step-feed was investigated as an attractive optimization strategy for enhancing COD and total phenols removal of the system and improving aerobic biodegradability of real coal gasification wastewater. Through the step-feed period, the maximum removal efficiencies of COD and total phenols reached 55-60% and 58-63% respectively in the system, at an influent flow distribution ratio of 0.2 and influent COD concentration of 2500 mg/L; the corresponding efficiencies were at low levels of 45-50% and 43-50% respectively at total HRT of 48 h during the single-feed period. The maximum specific methanogenic activity and substrate utilization rate were 592 ± 16 mg COD-CH(4)/(g VSS d) and 89 ± 12 mg phenol/(g VSS d) during the step-feed operation. After the anaerobic digestion with step-feed, the aerobic effluent COD concentration decreased from 270 ± 9 to 215 ± 10 mg/L. The results suggested that step-feed enhanced the degradation of refractory organics in the second reactor. PMID:21093254

  12. Integration of pneumatic fracturing with bioremediation from the enhanced removal of BTX from low permeability gasoline-contaminated soils

    SciTech Connect

    Venkatraman, S.N.; Kosson, D.S.; Schuring, J.R.; Boland, T.M.

    1995-11-01

    A pilot-scale evaluation of the integrated pneumatic fracturing and bioremediation system was carried out to demonstrate the enhanced removal of BTX from a gasoline contaminated, low permeability soil formation. The fracturing enhanced subsurface permeability by an average of over 36 times, and established an extended bioremediation zone supporting aerobic, denitrifying and methanogenic populations. Subsurface amendment injections consisting of phosphate and nitrogen were made periodically over a 50-week period to stimulate microbial activity. Results indicate that 79% of the soil-phase BTX was removed during the field test, with over 85% of the mass removed attributable to bioremediation.

  13. Phenol removal pretreatment process

    DOEpatents

    Hames, Bonnie R.

    2004-04-13

    A process for removing phenols from an aqueous solution is provided, which comprises the steps of contacting a mixture comprising the solution and a metal oxide, forming a phenol metal oxide complex, and removing the complex from the mixture.

  14. The optimization of phenolic compounds extraction from cactus pear (Opuntia ficus-indica) skin in a reflux system using response surface methodology

    PubMed Central

    Jorge, Aguirre Joya; Heliodoro, De La Garza Toledo; Alejandro, Zugasti Cruz; Ruth, Belmares Cerda; Noé, Aguilar Cristóbal

    2013-01-01

    Objective To extract, quantify, and evaluate the phenolic content in Opuntia ficus-indica skin for their antioxidant capacity with three different methods (ABTS, DPPH, and lipid oxidation) and to optimize the extraction conditions (time, temperature and ethanol concentration) in a reflux system. Methods The extraction process was done using a reflux system. A San Cristobal II experimental design with three variables and three levels was used. The variables evaluated were time of extraction (h), concentration of ethanol (%, v/v) and temperature (°C). The extraction process was optimized using a response surface methodology. Results It was observed that at higher temperature more phenolic compounds were extracted, but the antioxidant capacity was decreased. The optimum conditions for phenolic compounds extraction and antioxidant capacity mixing the three methods were as follows: 45% of ethanol, 80 °C and 2 hours of extraction. Values obtained in our results are little higher that other previously reported. Conclusions It can be concluded the by-products of Opuntia ficus-indica represent a good source of natural antioxidants with possible applications in food, cosmetics or drugs industries. PMID:23730555

  15. Living Composites of Electrospun Yeast Cells for Bioremediation and Ethanol Production.

    PubMed

    Letnik, Ilya; Avrahami, Ron; Rokem, J Stefan; Greiner, Andreas; Zussman, Eyal; Greenblatt, Charles

    2015-10-12

    The preparation of composites of living functional cells and polymers is a major challenge. We have fabricated such "living composites" by preparation of polymeric microtubes that entrap yeast cells. Our approach was the process of coaxial electrospinning in which a core containing the yeast was "spun" within a shell of nonbiodegradable polymer. We utilized the yeast Candida tropicalis, which was isolated from olive water waste. It is particularly useful since it degrades phenol and other natural polyphenols, and it is capable of accumulating ethanol. The electrospun yeast cells showed significant activity of bioremediation of phenol and produced ethanol, and, in addition, the metabolic processes remained active for a prolonged period. Comparison of electrospun cells to planktonic cells showed decreased cell activity; however, the olive water waste after treatment by the yeast was no longer toxic for Escherichia coli, suggesting that detoxification and prolonged viability and activity may outweigh the reduction of efficiency. PMID:26351729

  16. Solution thermodynamics for alkoxy phenols in alcohol and in water-alcohol systems

    SciTech Connect

    Beezer, A.E.; Hunter, W.H.; Lima, M.C.P.; Volpe, P.L.O.

    1986-04-01

    Solubilities have been measured for m-alkoxyphenols in water-alcohol mixtures. The alcohols ranged from the co-solvent methanol to the co-solute 1-octanol, and each alcohol was present at the saturating concentration of 1-octanol in water viz. 0.00316M. Plots of solubility vs. carbon number of the alcohols show discontinuities. Enthalpies of solution in these same solvent systems have also been measured. The enthalpies of solution and the derived enthalpies of transfer both support the observations on solubilities. The results are discussed on the basis of solvent-solute interactions and in terms of solute volumes.

  17. A rapid and miniaturized method for the selection of microbial phenol degraders using colourimetric microtitration.

    PubMed

    Fayidh, Mohammed A; Kallary, Sabina; Babu, P Azhagu Saravana; Sivarajan, M; Sukumar, M

    2015-06-01

    A high-throughput method is described, consisting of a colourimetric microtitration for screening phenol-degrading microorganisms, using a mixture of 4-aminoantipyrine and potassium ferricyanide as the colour indicator. This contemporary study summarizes a new method to determine phenol-degrading bacteria isolated from different areas. The method was used for testing a total of 72 bacteria collected from the natural environment and five known strains obtained from diagnostic and research laboratories employing 200 mg/L phenol (the linear range saturation concentration). Depending on the change in colour indicator, the degradation profiles of 11 strains of bacteria are shown, of which seven strains were able to degrade more than 80 % of phenol within 6-8 h, while the other four strains took 12-24 h. Two of the environmentally isolated strains showed high efficiency of phenol degradation and were confirmed by the high-performance liquid chromatography analysis. These strains were identified by 16S rRNA sequencing as unique (Escherichia coli moh1 and Bacillus cereus moh2) and were deposited in the GenBank of NCBI. Two pathogenic strains (Uropathogenic E. coli and Salmonella sp.) were found to be the fast degraders of phenol, which is of medical concern, as phenol is generally used as a disinfectant in hospitals. This method can be used for the estimation and screening of phenol degraders in a single step, for its application in bioremediation as well as in hospitals for screening the phenol resistance of pathogens. PMID:25842173

  18. Bioremediation Potential of Terrestrial Fuel Spills †

    PubMed Central

    Song, Hong-Gyu; Wang, Xiaoping; Bartha, Richard

    1990-01-01

    A bioremediation treatment that consisted of liming, fertilization, and tilling was evaluated on the laboratory scale for its effectiveness in cleaning up a sand, a loam, and a clay loam contaminated at 50 to 135 mg g of soil−1 by gasoline, jet fuel, heating oil, diesel oil, or bunker C. Experimental variables included incubation temperatures of 17, 27, and 37°C; no treatment; bioremediation treatment; and poisoned evaporation controls. Hydrocarbon residues were determined by quantitative gas chromatography or, in the case of bunker C, by residual weight determination. Four-point depletion curves were obtained for the described experimental variables. In all cases, the disappearance of hydrocarbons was maximal at 27°C and in response to bioremediation treatment. Poisoned evaporation controls underestimated the true biodegradation contribution, but nevertheless, they showed that biodegradation makes only a modest contribution to gasoline disappearance from soil. Bunker C was found to be structurally recalcitrant, with close to 80% persisting after 1 year of incubation. The three medium distillates, jet fuel, heating oil, and diesel oil, increased in persistence in the listed order but responded well to bioremediation treatment under all test conditions. With bioremediation treatment, it should be possible to reduce hydrocarbons to insignificant levels in contaminated soils within one growing season. PMID:16348139

  19. Diverse Metabolic Capacities of Fungi for Bioremediation.

    PubMed

    Deshmukh, Radhika; Khardenavis, Anshuman A; Purohit, Hemant J

    2016-09-01

    Bioremediation refers to cost-effective and environment-friendly method for converting the toxic, recalcitrant pollutants into environmentally benign products through the action of various biological treatments. Fungi play a major role in bioremediation owing to their robust morphology and diverse metabolic capacity. The review focuses on different fungal groups from a variety of habitats with their role in bioremediation of different toxic and recalcitrant compounds; persistent organic pollutants, textile dyes, effluents from textile, bleached kraft pulp, leather tanning industries, petroleum, polyaromatic hydrocarbons, pharmaceuticals and personal care products, and pesticides. Bioremediation of toxic organics by fungi is the most sustainable and green route for cleanup of contaminated sites and we discuss the multiple modes employed by fungi for detoxification of different toxic and recalcitrant compounds including prominent fungal enzymes viz., catalases, laccases, peroxidases and cyrochrome P450 monooxygeneses. We have also discussed the recent advances in enzyme engineering and genomics and research being carried out to trace the less understood bioremediation pathways. PMID:27407289

  20. Method for phosphate-accelerated bioremediation

    DOEpatents

    Looney, Brian B.; Lombard, Kenneth H.; Hazen, Terry C.; Pfiffner, Susan M.; Phelps, Tommy J.; Borthen, James W.

    1996-01-01

    An apparatus and method for supplying a vapor-phase nutrient to contaminated soil for in situ bioremediation. The apparatus includes a housing adapted for containing a quantity of the liquid nutrient, a conduit in fluid communication with the interior of the housing, means for causing a gas to flow through the conduit, and means for contacting the gas with the liquid so that a portion thereof evaporates and mixes with the gas. The mixture of gas and nutrient vapor is delivered to the contaminated site via a system of injection and extraction wells configured to the site. The mixture has a partial pressure of vaporized nutrient that is no greater than the vapor pressure of the liquid. If desired, the nutrient and/or the gas may be heated to increase the vapor pressure and the nutrient concentration of the mixture. Preferably, the nutrient is a volatile, substantially nontoxic and nonflammable organic phosphate that is a liquid at environmental temperatures, such as triethyl phosphate or tributyl phosphate.

  1. Evaluation of oil removal efficiency and enzymatic activity in some fungal strains for bioremediation of petroleum-polluted soils

    PubMed Central

    2012-01-01

    Background Petroleum pollution is a global disaster and there are several soil cleaning methods including bioremediation. Methods In a field study, fugal strains were isolated from oil-contaminated sites of Arak refinery (Iran) and their growth ability was checked in potato dextrose agar (PDA) media containing 0-10% v/v crude oil, the activity of three enzymes (Catalase, Peroxidase and Phenol Oxidase) was evaluated in the fungal colonies and bioremediation ability of the fungi was checked in the experimental pots containing 3 kg sterilized soil and different concentrations of petroleum (0-10% w/w). Results Four fungal strains, Acromonium sp., Alternaria sp., Aspergillus terreus and Penicillium sp., were selected as the most resistant ones. They were able to growth in the subjected concentrations and Alternaria sp. showed the highest growth ability in the petroleum containing media. The enzyme assay showed that the enzymatic activity was increased in the oil-contaminated media. Bioremediation results showed that the studied fungi were able to decrease petroleum pollution. The highest petroleum removing efficiency of Aspergillus terreus, Penicillium sp., Alternaria sp. and Acromonium sp. was evaluated in the 10%, 8%, 8% and 2% petroleum pollution respectively. Conclusions Fungi are important microorganisms in decreasing of petroleum pollution. They have bioremediation potency that is related to their enzymatic activities. PMID:23369665

  2. Key Factors Controlling the Applicability and Efficiency of Bioremediation of Chlorinated Ethenes In Situ

    NASA Astrophysics Data System (ADS)

    Zhang, M.; Yoshikawa, M.; Takeuchi, M.; Komai, T.

    2012-12-01

    Bioremediation has been considered as one of environmentally friendly and cost effective approaches for cleaning up the sites polluted by organic contaminants, such as chlorinated ethenes. Although bioremediation, in its widest sense, is not new, and many researches have been performed on bioremediation of different kinds of pollutants, an effective design and implication of in situ bioremediation still remains a challenging problem because of the complexity. Many factors may affect the applicability and efficiency of bioremediation of chlorinated ethenes in situ, which include the type and concentration of contaminants, biological, geological and hydro-geological conditions of the site, physical and chemical characteristics of groundwater and soils to be treated, as well as the constraints in engineering. In this presentation, an overview together with a detailed discussion on each factor will be provided. The influences of individual factors are discussed using the data obtained or cited from different sites and experiments, and thus under different environmental conditions. The results of this study illustrated that 1) the establishment of microbial consortium is of crucial importance for a complete degradation of chlorinated ethenes, 2) in situ control of favorable conditions for increasing microbial activities for bio-degradation through a designed pathway is the key to success, 3) the focus of a successful remediation system is to design an effective delivery process that is capable of producing adequate amendment mixing of contaminant-degrading bacteria, appropriate concentrations of electron acceptors, electron donors, and microbial nutrients in the subsurface treatment area.

  3. Electrokinetic-enhanced bioremediation of organic contaminants: a review of processes and environmental applications.

    PubMed

    Gill, R T; Harbottle, M J; Smith, J W N; Thornton, S F

    2014-07-01

    There is current interest in finding sustainable remediation technologies for the removal of contaminants from soil and groundwater. This review focuses on the combination of electrokinetics, the use of an electric potential to move organic and inorganic compounds, or charged particles/organisms in the subsurface independent of hydraulic conductivity; and bioremediation, the destruction of organic contaminants or attenuation of inorganic compounds by the activity of microorganisms in situ or ex situ. The objective of the review is to examine the state of knowledge on electrokinetic bioremediation and critically evaluate factors which affect the up-scaling of laboratory and bench-scale research to field-scale application. It discusses the mechanisms of electrokinetic bioremediation in the subsurface environment at different micro and macroscales, the influence of environmental processes on electrokinetic phenomena and the design options available for application to the field scale. The review also presents results from a modelling exercise to illustrate the effectiveness of electrokinetics on the supply electron acceptors to a plume scale scenario where these are limiting. Current research needs include analysis of electrokinetic bioremediation in more representative environmental settings, such as those in physically heterogeneous systems in order to gain a greater understanding of the controlling mechanisms on both electrokinetics and bioremediation in those scenarios. PMID:24875868

  4. Review of chlorinated phenols

    SciTech Connect

    Exon, J.H.

    1984-12-01

    The chlorinated phenols are a group of 19 isomers composed of phenol with substituted chlorines. These chemicals are readily soluble in organic solvents but only slightly soluble in water, except for the chlorophenate salts. Chlorophenols with less than 3 chlorines are not used extensively except in the production of higher chlorophenols and chlorophenyloxyacetic acid herbicides. Pentachlorophenol and some tetrachlorophenols are used worldwide, primarily as wood preservatives or fungicides. Residues of chlorophenols have been found worldwide in soil, water and air samples, in food products, and in human and animal tissues and body fluids. Environmental contamination with these chemicals occurs from industrial effluents, agricultural runoff, breakdown of chlorophenyloxyacetic acid herbicides and hexachlorobenzene, and from spontaneous formation following chlorination of water for disinfection and deodorization. The acute toxicity of these chemicals is relatively low and little is known concerning their chronic effects. Chlorophenols have not been shown conclusively to be mutagens, teratogens or carcinogens. However, these compounds may act as promotors or cocarcinogens and the immune system is particularly sensitive to their toxic effects. Transplacental exposure to chlorophenols may result in embryotoxicity and abortion. The major mode of toxic action is as uncouplers of oxidative phosphorylation. The toxicity of chlorophenols decreases with decreasing chlorination. These chemicals are mild hepatotoxins and are stored mainly in hepatic and renal tissues.

  5. Strategies for chromium bioremediation of tannery effluent.

    PubMed

    Garg, Satyendra Kumar; Tripathi, Manikant; Srinath, Thiruneelakantan

    2012-01-01

    Bioremediation offers the possibility of using living organisms (bacteria, fungi, algae,or plants), but primarily microorganisms, to degrade or remove environmental contaminants, and transform them into nontoxic or less-toxic forms. The major advantages of bioremediation over conventional physicochemical and biological treatment methods include low cost, good efficiency, minimization of chemicals, reduced quantity of secondary sludge, regeneration of cell biomass, and the possibility of recover-ing pollutant metals. Leather industries, which extensively employ chromium compounds in the tanning process, discharge spent-chromium-laden effluent into nearby water bodies. Worldwide, chromium is known to be one of the most common inorganic contaminants of groundwater at pollutant hazardous sites. Hexavalent chromium poses a health risk to all forms of life. Bioremediation of chromium extant in tannery waste involves different strategies that include biosorption, bioaccumulation,bioreduction, and immobilization of biomaterial(s). Biosorption is a nondirected physiochemical interaction that occurs between metal species and the cellular components of biological species. It is metabolism-dependent when living biomass is employed, and metabolism-independent in dead cell biomass. Dead cell biomass is much more effective than living cell biomass at biosorping heavy metals, including chromium. Bioaccumulation is a metabolically active process in living organisms that works through adsorption, intracellular accumulation, and bioprecipitation mechanisms. In bioreduction processes, microorganisms alter the oxidation/reduction state of toxic metals through direct or indirect biological and chemical process(es).Bioreduction of Cr6+ to Cr3+ not only decreases the chromium toxicity to living organisms, but also helps precipitate chromium at a neutral pH for further physical removal,thus offering promise as a bioremediation strategy. However, biosorption, bioaccumulation, and

  6. MTBE BIODEGRADATION AND BIOREMEDIATION (ROCKY GAP, MD)

    EPA Science Inventory

    MTBE contamination in ground water at gasoline spill sites can be treated with in situ aerobic bioremediation. All that is usually necessary is to provide sufficient oxygen to meet the oxygen demand of the fuel components in the ground water. The field scale performance of the ...

  7. MTBE BIODEGRADATION AND BIOREMEDIATION (ROCKY GAP, MD*)

    EPA Science Inventory

    MTBE contamination in ground water at gasoline spill sites can be treated with in situ aerobic bioremediation. All that is usually necessary is to provide sufficient oxygen to meet the oxygen demand of the fuel components in the ground water. The field scale performance of the ...

  8. BIOREMEDIATION AT WOOD-PRESERVING SITES

    EPA Science Inventory

    The removal of organic compounds from ground water during bioremediation at wood-preserving sites is a function of the stoichiometric demand for electron acceptors (oxygen, nitrate, and sulfate) to metabolize the organic contaminants and the supply of the electron acceptors in th...

  9. In-situ bioremediation via horizontal wells

    SciTech Connect

    Hazen, T.C.; Looney, B.B.; Enzien, M.; Franck, M.M.; Fliermans, C.B.; Eddy, C.A.

    1993-12-31

    This project is designed to demonstrate in situ bioremediation of groundwater and sediment contaminated with chlorinated solvents. Indigenous microorganisms were stimulated to degrade TCE, PCE and their daughter products in situ by addition of nutrients to the contaminated zone. In situ biodegradation is a highly attractive technology for remediation because contaminants are destroyed, not simply moved to another location or immobilized, thus decreasing costs, risks, and time, while increasing efficiency and public and regulatory acceptability. Bioremediation has been found to be among the least costly technologies in applications where it will work (Radian 1989). Subsurface soils and water adjacent to an abandoned process sewer line at the SRS have been found to have elevated levels of TCE (Marine and Bledsoe 1984). This area of subsurface and groundwater contamination is the focus of a current integrated demonstration of new remediation technologies utilizing horizontal wells. Bioremediation has the potential to enhance the performance of in situ air stripping as well as offering stand-alone remediation of this and other contaminated sites (Looney et al. 1991). Horizontal wells could also be used to enhance the recovery of groundwater contaminants for bioreactor conversions from deep or inaccessible areas (e.g., under buildings) and to enhance the distribution of nutrient or microbe additions in an in situ bioremediation.

  10. Phytochemical phenolics in organically grown vegetables.

    PubMed

    Young, Janice E; Zhao, Xin; Carey, Edward E; Welti, Ruth; Yang, Shie-Shien; Wang, Weiqun

    2005-12-01

    Fruit and vegetable intake is inversely correlated with risks for several chronic diseases in humans. Phytochemicals, and in particular, phenolic compounds, present in plant foods may be partly responsible for these health benefits through a variety of mechanisms. Since environmental factors play a role in a plant's production of secondary metabolites, it was hypothesized that an organic agricultural production system would increase phenolic levels. Cultivars of leaf lettuce, collards, and pac choi were grown either on organically certified plots or on adjacent conventional plots. Nine prominent phenolic agents were quantified by HPLC, including phenolic acids (e. g. caffeic acid and gallic acid) and aglycone or glycoside flavonoids (e. g. apigenin, kaempferol, luteolin, and quercetin). Statistically, we did not find significant higher levels of phenolic agents in lettuce and collard samples grown organically. The total phenolic content of organic pac choi samples as measured by the Folin-Ciocalteu assay, however, was significantly higher than conventional samples (p < 0.01), and seemed to be associated with a greater attack the plants in organic plots by flea beetles. These results indicated that although organic production method alone did not enhance biosynthesis of phytochemicals in lettuce and collards, the organic system provided an increased opportunity for insect attack, resulting in a higher level of total phenolic agents in pac choi. PMID:16302198

  11. Monitoring of white-rot fungus during bioremediation of polychlorinated dioxin-contaminated fly ash.

    PubMed

    Suhara, H; Daikoku, C; Takata, H; Suzuki, S; Matsufuji, Y; Sakai, K; Kondo, R

    2003-10-01

    Bioremediation is a low-cost treatment alternative for the cleanup of polychlorinated-dioxin-contaminated soils and fly ash when pollution spread is wide-ranging. An interesting fungus, Ceriporia sp. MZ-340, with a high ability to degrade dioxin, was isolated from white rotten wood of a broadleaf tree from Kyushu Island in Japan. We have attempted to use the fungus for bioremediation of polychlorinated-dioxin-contaminated soil on site. However, we have to consider that this trial has the potential problem of introducing a biohazard to a natural ecosystem if this organism is naturalized. We have therefore developed a monitoring system for the introduced fungus as a part of the examination and evaluation of bioremediation in our laboratory. We have also developed a PCR-based assay to reliably detect the fungus at the bioremediation site. DNA isolated from the site was amplified by PCR using a specific primer derived from internal transcribed spacer region (ITS: ITS1, 5.8S rDNA and ITS2) sequences of Ceriporia sp. MZ-340. We successfully monitored Ceriporia sp. MZ-340 down to 100 fg/ micro l DNA and down to 2 mg/g mycelium. We also successfully monitored the fungus specifically at the bioremediation site. The polychlorinated dibenzo- p-dioxin and polychlorinated dibenzofuran content was observed to decrease in response to treatment with the fungus. The species-specific PCR technique developed in the present work is useful in evaluating the possibility of on-site bioremediation using the fungus Ceriporia sp. MZ-340. PMID:12827316

  12. Field evaluations of marine oil spill bioremediation.

    PubMed Central

    Swannell, R P; Lee, K; McDonagh, M

    1996-01-01

    Bioremediation is defined as the act of adding or improving the availability of materials (e.g., nutrients, microorganisms, or oxygen) to contaminated environments to cause an acceleration of natural biodegradative processes. The results of field experiments and trials following actual spill incidents have been reviewed to evaluate the feasibility of this approach as a treatment for oil contamination in the marine environment. The ubiquity of oil-degrading microorganisms in the marine environment is well established, and research has demonstrated the capability of the indigenous microflora to degrade many components of petroleum shortly after exposure. Studies have identified numerous factors which affect the natural biodegradation rates of oil, such as the origin and concentration of oil, the availability of oil-degrading microorganisms, nutrient concentrations, oxygen levels, climatic conditions, and sediment characteristics. Bioremediation strategies based on the application of fertilizers have been shown to stimulate the biodegradation rates of oil in aerobic intertidal sediments such as sand and cobble. The ratio of oil loading to nitrogen concentration within the interstitial water has been identified to be the principal controlling factor influencing the success of this bioremediation strategy. However, the need for the seeding of natural environments with hydrocarbon-degrading bacteria has not been clearly demonstrated under natural environmental conditions. It is suggested that bioremediation should now take its place among the many techniques available for the treatment of oil spills, although there is still a clear need to set operational limits for its use. On the basis of the available evidence, we have proposed preliminary operational guidelines for bioremediation on shoreline environments. PMID:8801437

  13. Field evaluations of marine oil spill bioremediation.

    PubMed

    Swannell, R P; Lee, K; McDonagh, M

    1996-06-01

    Bioremediation is defined as the act of adding or improving the availability of materials (e.g., nutrients, microorganisms, or oxygen) to contaminated environments to cause an acceleration of natural biodegradative processes. The results of field experiments and trials following actual spill incidents have been reviewed to evaluate the feasibility of this approach as a treatment for oil contamination in the marine environment. The ubiquity of oil-degrading microorganisms in the marine environment is well established, and research has demonstrated the capability of the indigenous microflora to degrade many components of petroleum shortly after exposure. Studies have identified numerous factors which affect the natural biodegradation rates of oil, such as the origin and concentration of oil, the availability of oil-degrading microorganisms, nutrient concentrations, oxygen levels, climatic conditions, and sediment characteristics. Bioremediation strategies based on the application of fertilizers have been shown to stimulate the biodegradation rates of oil in aerobic intertidal sediments such as sand and cobble. The ratio of oil loading to nitrogen concentration within the interstitial water has been identified to be the principal controlling factor influencing the success of this bioremediation strategy. However, the need for the seeding of natural environments with hydrocarbon-degrading bacteria has not been clearly demonstrated under natural environmental conditions. It is suggested that bioremediation should now take its place among the many techniques available for the treatment of oil spills, although there is still a clear need to set operational limits for its use. On the basis of the available evidence, we have proposed preliminary operational guidelines for bioremediation on shoreline environments. PMID:8801437

  14. DEVELOPMENT AND APPLICATION OF PROTOCOLS FOR EVALUATION OF OIL SPILL BIOREMEDIATION (RESEARCH BRIEF)

    EPA Science Inventory

    Protocols were developed and evaluated to assess the efficacy and environmental safety of commercial oil spill bioremediation agents (CBAs). Test systems that simulate oil slicks on open water or oiled sandy beaches were used to test the effectiveness of CBAs. Gravimetric and gas...

  15. Method for enhanced longevity of in situ microbial filter used for bioremediation

    DOEpatents

    Carman, M. Leslie; Taylor, Robert T.

    1999-01-01

    An improved method for in situ microbial filter bioremediation having increasingly operational longevity of an in situ microbial filter emplaced into an aquifer. A method for generating a microbial filter of sufficient catalytic density and thickness, which has increased replenishment interval, improved bacteria attachment and detachment characteristics and the endogenous stability under in situ conditions. A system for in situ field water remediation.

  16. DEMONSTRATION BULLETIN: EX-SITU ANAEROBIC BIOREMEDIATION TECHNOLOGY - TNT - J.R. SIMPLOT COMPANY

    EPA Science Inventory

    The J. R. Simplot Ex-Situ Anaerobic Bioremediation System, also known as the J.R. Simplot Anaerobic Biological Remediaton Process (the SABRE™ Process), is a technology designed to destroy nitroaromatic and energetic compounds. The process does not evolve any known toxic intermedi...

  17. UTILIZATION OF TREATABILITY AND PILOT TESTS TO PREDICT CAH BIOREMEDIATION (Battelle)

    EPA Science Inventory

    Multiple tools have been suggested to help in the design of enhanced anaerobic bioremediation systems for CAHs:
    Extensive high quality microcosm testing followed by small-scale, thoroughly observed, induced flow field pilot tests (i.e. RABITT Protocol, Morse 1998)
    More...

  18. Discovery of plant phenolic compounds that act as type III secretion system inhibitors or inducers of the fire blight pathogen, Erwinia amylovora.

    PubMed

    Khokhani, Devanshi; Zhang, Chengfang; Li, Yan; Wang, Qi; Zeng, Quan; Yamazaki, Akihiro; Hutchins, William; Zhou, Shan-Shan; Chen, Xin; Yang, Ching-Hong

    2013-09-01

    Erwinia amylovora causes a devastating disease called fire blight in rosaceous plants. The type III secretion system (T3SS) is one of the important virulence factors utilized by E. amylovora in order to successfully infect its hosts. By using a green fluorescent protein (GFP) reporter construct combined with a high-throughput flow cytometry assay, a library of phenolic compounds and their derivatives was studied for their ability to alter the expression of the T3SS. Based on the effectiveness of the compounds on the expression of the T3SS pilus, the T3SS inhibitors 4-methoxy-cinnamic acid (TMCA) and benzoic acid (BA) and one T3SS inducer, trans-2-(4-hydroxyphenyl)-ethenylsulfonate (EHPES), were chosen for further study. Both the T3SS inhibitors (TMCA and BA) and the T3SS inducer (EHPES) were found to alter the expression of T3SS through the HrpS-HrpL pathway. Additionally, TMCA altered T3SS expression through the rsmBEa-RsmAEa system. Finally, we found that TMCA and BA weakened the hypersensitive response (HR) in tobacco by suppressing the T3SS of E. amylovora. In our study, we identified phenolic compounds that specifically targeted the T3SS. The T3SS inhibitor may offer an alternative approach to antimicrobial therapy by targeting virulence factors of bacterial pathogens. PMID:23770912

  19. Lipid encapsulated phenolics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phenolic compounds have numerous health benefits when included in the human diet and have emerged as a functional food and feed additive. Current sources of phenolics include commodity grains such as corn, oat, and wheat but may also be obtained as a co-product from agricultural residues and other l...

  20. REVIEW OF CHLORINATED PHENOLS

    EPA Science Inventory

    The chlorinated phenols are a group of 19 isomers composed of phenol with substituted chlorines. These chemicals are readily soluble in organic solvents but only slightly soluble in water, except for the chlorophenate salts. Chlorophenols with less than 3 chlorines are not used e...

  1. Phenolic Molding Compounds

    NASA Astrophysics Data System (ADS)

    Koizumi, Koji; Charles, Ted; de Keyser, Hendrik

    Phenolic Molding Compounds continue to exhibit well balanced properties such as heat resistance, chemical resistance, dimensional stability, and creep resistance. They are widely applied in electrical, appliance, small engine, commutator, and automotive applications. As the focus of the automotive industry is weight reduction for greater fuel efficiency, phenolic molding compounds become appealing alternatives to metals. Current market volumes and trends, formulation components and its impact on properties, and a review of common manufacturing methods are presented. Molding processes as well as unique advanced techniques such as high temperature molding, live sprue, and injection/compression technique provide additional benefits in improving the performance characterisitics of phenolic molding compounds. Of special interest are descriptions of some of the latest innovations in automotive components, such as the phenolic intake manifold and valve block for dual clutch transmissions. The chapter also characterizes the most recent developments in new materials, including long glass phenolic molding compounds and carbon fiber reinforced phenolic molding compounds exhibiting a 10-20-fold increase in Charpy impact strength when compared to short fiber filled materials. The role of fatigue testing and fatigue fracture behavior presents some insight into long-term reliability and durability of glass-filled phenolic molding compounds. A section on new technology outlines the important factors to consider in modeling phenolic parts by finite element analysis and flow simulation.

  2. Bromination of Phenol

    ERIC Educational Resources Information Center

    Talbot, Christopher

    2013-01-01

    This "Science note" examines the bromination of phenol, a reaction that is commonly taught at A-level and IB (International Baccalaureate) as an example of electrophilic substitution. Phenol undergoes bromination with bromine or bromine water at room temperature. A white precipitate of 2,4,6-tribromophenol is rapidly formed. This…

  3. Biodegradation of phenolic compounds by Basidiomycota and its phenol oxidases: A review.

    PubMed

    Martínková, L; Kotik, M; Marková, E; Homolka, L

    2016-04-01

    The phylum Basidiomycota include organisms with enormous bioremediation potential. A variety of processes were proposed at the lab scale for using these fungi and their phenol oxidases in the degradation of phenolics. Here we present a survey of this topic using literature published mostly over the last 10 years. First, the sources of the enzymes are summarized. The laccase and tyrosinase were mainly from Trametes versicolor and Agaricus bisporus, respectively. Recently, however, new promising wild-type producers of the enzymes have emerged and a number of recombinant strains were also constructed, based mainly on yeasts or Aspergillus strains as hosts. The next part of the study summarizes the enzyme and whole-cell applications for the degradation of phenols, polyphenols, cresols, alkylphenols, naphthols, bisphenols and halogenated (bis)phenols in model mixtures or real wastewaters from the food, paper and coal industries, or municipal and hospital sewage. The enzymes were applied as free (crude or purified) enzymes or as enzymes immobilized in various supports or CLEAs, and optionally recycled or used in continuous mode. Alternatively, growing cultures or harvested mycelia were used instead. The products, which were characterized as quinones and their polymers in some cases, could be eliminated by filtration, flocculation or adsorption onto chitosan. The purity of a treated wastewater was monitored using a sensitive aquatic organism. It is concluded that low-cost sources of these enzymes should be searched for and the benefits of enzymatic, biological and physico-chemical methods could be combined to make the processes fit for industrial use. PMID:26874626

  4. Enzymatic oxidation of phenolic compounds in coffee processing wastewater.

    PubMed

    Torres, Juliana Arriel; Batista Chagas, Pricila Maria; Silva, Maria Cristina; dos Santos, Custódio Donizete; Duarte Corrêa, Angelita

    2016-01-01

    Peroxidases can be used in the treatment of wastewater containing phenolic compounds. The effluent from the wet processing of coffee fruits contains high content of these pollutants and although some studies propose treatments for this wastewater, none targets specifically the removal of these recalcitrant compounds. This study evaluates the potential use of different peroxidase sources in the oxidation of caffeic acid and of total phenolic compounds in coffee processing wastewater (CPW). The identification and quantification of phenolic compounds in CPW was performed and caffeic acid was found to be the major phenolic compound. Some factors, such as reaction time, pH, amount of H2O2 and enzyme were evaluated, in order to determine the optimum conditions for the enzyme performance for maximum oxidation of caffeic acid. The turnip peroxidase (TPE) proved efficient in the removal of caffeic acid, reaching an oxidation of 51.05% in just 15 minutes of reaction. However, in the bioremediation of the CPW, the horseradish peroxidase (HRP) was more efficient with 32.70%±0.16 of oxidation, followed by TPE with 18.25%±0.11. The treatment proposed in this work has potential as a complementary technology, since the efficiency of the existing process is intimately conditioned to the presence of these pollutants. PMID:26744933

  5. Bioremediation in Germany: Markets, technologies, and leading companies

    SciTech Connect

    Raphael, T.

    1995-12-31

    Bioremediation has become an internationally accepted remediation tool. Commercial bioremediation activities take place in many European countries, but Germany and the Netherlands are the clear European leaders, with both having a long history of public and private sector activity in biological technologies. The German bioremediation market has been driven by government regulation, in particular the waste laws that apply to contaminated soils. The 1994 German market for bioremediation is estimated at $70 to 100 million (US $). There are at least 150 companies active in bioremediation in Germany, most of which practice bioremediation of hydrocarbon-contaminated soils, either in situ or ex situ. Because of their predominance in the current European market, German firms are well positioned to expand into those nations in the European Union (EU) currently lacking an environmental business infrastructure.

  6. DEVELOPMENT OF BIOAVAILABILITY AND BIOKINETICS DETERMINATION METHODS FOR ORGANIC POLLUTANTS IN SOIL TO ENHANCE IN-SITU AND ON-SITE BIOREMEDIATION

    EPA Science Inventory

    Determination of biodegradation rates of organics in soil slurry and compacted soil systems is essential for evaluating the efficacy of bioremediation for treatment of contaminated soils. In this paper, a systematic protocol has been developed for evaluating bioknetic and transp...

  7. Tapping bioremediation's potential -- A matter of sweat and tiers

    SciTech Connect

    Merski, A.T.; Griffin, W.M. )

    1993-03-01

    Bioremediation's potential for treating environmental contamination is gaining greater recognition among regulators and the regulated community. For example, biological treatment is routinely applied to municipal wastewater, which typically contains readily biodegradable materials. Industrial wastewaters, by contrast, often contain higher concentrations of materials that present unique challenges to biological treatment. In both areas, biological treatment has succeeded by using contained, relatively controlled systems engineered to optimize performance of the biological component. Uncontrolled releases into such matrices as soil, and fresh and marine waters increase the complexity of the biological challenge, requiring development of novel products and procedures for efficient biological treatment and monitoring. One of the goals of the National Environmental Technology Applications Corporation (NETAC; Pittsburgh) is to support scientific development of bioremediation technology. NETAC is a non-profit corporation formed in 1988 through a cooperative agreement between EPA and the University of Pittsburgh Trust. Its overall mission is to accelerate development, application and commercialization of priority environmental technologies for national and international markets. NETAC provides technical and business expertise to assist in evaluating, commercializing and publicizing new environmental technologies. The organization assumes no financial interest in any technology but provides independent third-party support and analysis on a fee-for-service basis to technology users and developers.

  8. Stimulating sediment bioremediation with benthic microbial fuel cells.

    PubMed

    Li, Wen-Wei; Yu, Han-Qing

    2015-01-01

    Efficient and sustainable technologies for cleaning up of contaminated sediments are under urgent demand. Bioremediation by utilizing the natural metabolic activities of sediment-inhabited microorganisms has been widely accepted as a viable option, but the relatively low efficiency and poor controllability severely limite its application. Here, we bring out the concept that electrochemical approaches may be used as an efficient means to stimulate sediment bioremediation. Although still at the very beginning, benthic microbial fuel cells (BMFC) as a remediation technology show many potential benefits, such as accelerated decontamination, self-sustained operation, relatively easy deployment and control, and environmental benignity. The unique features of BMFC setup and operation also give rise to substantially different challenges compared to conventional MFCs. In this review, we present a critical overview on the characteristics, possible application niches, and state-of-the-art progress of this technology. Especially, the current limitations in respect of system design, electrode selection, microbial control and selection of deployment environment are discussed in details, and the needed future research endeavors to promote its practical application are highlighted. PMID:25560929

  9. Enhancement of Phenol Biodegradation by Pseudochrobactrum sp. through Ultraviolet-Induced Mutation

    PubMed Central

    Mao, Zhen; Yu, Chenyang; Xin, Lingling

    2015-01-01

    The phenol-degrading efficiency of Pseudochrobactrum sp. was enhanced by ultraviolet (UV) irradiation. First, a bacterial strain, Pseudochrobactrum sp. XF1, was isolated from the activated sludge in a coking plant. It was subjected to mutation by UV radiation for 120 s and a mutant strain with higher phenol-degrading efficiency, Pseudochrobactrum sp. XF1-UV, was selected. The mutant strain XF1-UV was capable of degrading 1800 mg/L phenol completely within 48 h and had higher tolerance to hydrogen ion concentration and temperature variation than the wild type. Haldane’s kinetic model was used to fit the exponential growth data and the following kinetic parameters were obtained: μmax = 0.092 h−1, Ks = 22.517 mg/L, and Ki = 1126.725 mg/L for XF1, whereas μmax = 0.110 h−1, Ks = 23.934 mg/L, and Ki = 1579.134 mg/L for XF1-UV. Both XF1 and XF1-UV degraded phenol through the ortho-pathway; but the phenol hydroxylase activity of XF1-UV1 was higher than that of XF1, therefore, the mutant strain biodegraded phenol faster. Taken together, our results suggest that Pseudochrobactrum sp. XF1-UV could be a promising candidate for bioremediation of phenol-containing wastewaters. PMID:25837630

  10. Phenol degradation by halophilic fungal isolate JS4 and evaluation of its tolerance of heavy metals.

    PubMed

    Jiang, Yu; Shang, Yu; Yang, Kai; Wang, Hongyu

    2016-02-01

    Phenol is one of the most common pollutants in many kinds of industrial wastewater, some of which are in high salinity, resulting in more difficulties of biodegradation. In this work, a halophilic strain capable of utilizing phenol as sole source of carbon and energy in both hypersaline and no-salt media was isolated and identified as genus Debaryomyces. The optimization of environmental parameters including phenol concentration, pH, dissolved oxygen as well as salinity was carried out and tolerance of heavy metals by the strain was evaluated. The strain Debaryomyces sp. was able to grow in culture when initial phenol concentration, pH, agitation and salinity were at wide ranges (0-1200 mg L(-1), 4.0-10.0, 50-200 rpm, 0 %-15 %, respectively). High removal efficiency was hardly affected in the presence of 5 mM of Zn (II) and Mn (II). Under optimal conditions (pH 6.0, 200 rpm, 1 % of salinity without heavy metals), 500 mg L(-1) of phenol could be completely degraded within 32 h. The high removal efficiency of phenol by the strain with significant variations of process parameters might contribute to the bioremediation of phenol-polluted environments under hypersaline or no-salt conditions. PMID:26610801

  11. Molecular Tools for Monitoring and Validating Bioremediation

    NASA Astrophysics Data System (ADS)

    Stenuit, Ben; Eyers, Laurent; Schuler, Luc; George, Isabelle; Agathos, Spiros N.

    Bioremediation is now in a position to take advantage of genomic-driven strategies to analyze, monitor and assess its course by considering multiple micro-organisms with various genomes, expressed transcripts and proteins. High-throughput methodologies, including microarrays, fingerprinting, real-time PCR, metagenomics and metaproteomics, show great promise in our environmental interventions against recalcitrant contaminants such as 2,4,6-trinitrotoluene (TNT) that we have been studying for many years. The emerging genomic and metagenomic methodologies will allow us to promote or restore environmental health in impacted sites, monitor remediation activities, identify key microbial players and processes, and finally compile an intelligent database of genes for targeted use in bioremediation.

  12. Natural and accelerated bioremediation research program plan

    SciTech Connect

    1995-09-01

    This draft plan describes a ten-year program to develop the scientific understanding needed to harness and develop natural and enhanced biogeochemical processes to bioremediate contaminated soils, sediments and groundwater at DOE facilities. The Office of Health and Environmental Research (OHER) developed this program plan, with advice and assistance from DOE`s Office of Environmental Management (EM). The program builds on OHER`s tradition of sponsoring fundamental research in the life and environmental sciences and was motivated by OHER`s and Office of Energy Research`s (OER`s) commitment to supporting DOE`s environmental management mission and the belief that bioremediation is an important part of the solution to DOE`s environmental problems.

  13. Bioremediation of petroleum-contaminated soil

    SciTech Connect

    Pearce, K.; Snyman, H.G.; Oellermann, R.A.; Gerber, A.

    1995-12-31

    A pilot-scale study was conducted to evaluate the application of land-farming techniques in bioremediating a soil highly contaminated with petroleum products. A commercial biosupplement, and one prepared with indigenous microorganisms from the contaminated soil, were tested. Application of either of the biosupplements, in addition to the control of pH, moisture, and oxygen levels, resulted in a 94% reduction of the initial total petroleum hydrocarbon concentration (TPHC) (32% mass/mass) over a 70-day period. Implementation of these findings at full scale to bioremediate highly weathered petroleum products showed an average reduction of 89% over 5.5 months. Target levels of 1,400 mg/kg soil were reached from an initial average TPHC concentration of 12,200 mg/kg soil.

  14. Controlling the catalytic aerobic oxidation of phenols.

    PubMed

    Esguerra, Kenneth Virgel N; Fall, Yacoub; Petitjean, Laurène; Lumb, Jean-Philip

    2014-05-28

    The oxidation of phenols is the subject of extensive investigation, but there are few catalytic aerobic examples that are chemo- and regioselective. Here we describe conditions for the ortho-oxygenation or oxidative coupling of phenols under copper (Cu)-catalyzed aerobic conditions that give rise to ortho-quinones, biphenols or benzoxepines. We demonstrate that each product class can be accessed selectively by the appropriate choice of Cu(I) salt, amine ligand, desiccant and reaction temperature. In addition, we evaluate the effects of substituents on the phenol and demonstrate their influence on selectivity between ortho-oxygenation and oxidative coupling pathways. These results create an important precedent of catalyst control in the catalytic aerobic oxidation of phenols and set the stage for future development of catalytic systems and mechanistic investigations. PMID:24784319

  15. Use of molecular techniques in bioremediation.

    PubMed

    Płaza, G; Ulfig, K; Hazen, T C; Brigmon, R L

    2001-01-01

    In a practical sense, biotechnology is concerned with the production of commercial products generated by biological processes. More formally, biotechnology may be defined as "the application of scientific and engineering principles to the processing of material by biological agents to provide goods and services" (Cantor, 2000). From a historical perspective, biotechnology dates back to the time when yeast was first used for beer or wine fermentation, and bacteria were used to make yogurt. In 1972, the birth of recombinant DNA technology moved biotechnology to new heights and led to the establishment of a new industry. Progress in biotechnology has been truly remarkable. Within four years of the discovery of recombinant DNA technology, genetically modified organisms (GMOs) were making human insulin, interferon, and human growth hormone. Now, recombinant DNA technology and its products--GMOs are widely used in environmental biotechnology (Glick and Pasternak, 1988; Cowan, 2000). Bioremediation is one of the most rapidly growing areas of environmental biotechnology. Use of bioremediation for environmental clean up is popular due to low costs and its public acceptability. Indeed, bioremediation stands to benefit greatly and advance even more rapidly with the adoption of molecular techniques developed originally for other areas of biotechnology. The 1990s was the decade of molecular microbial ecology (time of using molecular techniques in environmental biotechnology). Adoption of these molecular techniques made scientists realize that microbial populations in the natural environments are much more diverse than previously thought using traditional culture methods. Using molecular ecological methods, such as direct DNA isolation from environmental samples, denaturing gradient gel electrophoresis (DGGE), PCR methods, nucleic acid hybridization etc., we can now study microbial consortia relevant to pollutant degradation in the environment. These techniques promise to

  16. Bioremediation Education Science and Technology (BEST) Program Annual Report 1999

    SciTech Connect

    Hazen, Terry C.

    2000-07-01

    The Bioremediation, Education, Science and Technology (BEST) partnership provides a sustainable and contemporary approach to developing new bioremedial technologies for US Department of Defense (DoD) priority contaminants while increasing the representation of underrepresented minorities and women in an exciting new biotechnical field. This comprehensive and innovative bioremediation education program provides under-represented groups with a cross-disciplinary bioremediation cirruculum and financial support, coupled with relevant training experiences at advanced research laboratories and field sites. These programs are designed to provide a stream of highly trained minority and women professionals to meet national environmental needs.

  17. In-situ bioremediation: Or how to get nutrients to all the contaminated soil

    SciTech Connect

    Jackson, D.S.; Scovazzo, P.

    1994-12-31

    Petroleum contamination is a pervasive environmental problem. Bioremediation is winning favor primarily because the soil may be treated on site and systems can be installed to operate without interfering with facility activities. Although bioremediation has been utilized for many years, its acceptance as a cost-effective approach is only now being realized. KEMRON applied in-situ bioremediation at a retired rail yard which had maintained a diesel locomotive refueling station supplied by two 20,000 gallon above ground storage tanks. Contamination originated from both spillage at the pumps and leaking fuel distribution lines. The contamination spread over a 3 acre area from the surface to a depth of up to 20 feet. Levels of diesel contamination found in the soil ranged from less than a 100 ppm to more than 25,000 ppm. The volume of soil which ultimately required treatment was more than 60,000 cubic yards. Several remedial options were examined including excavation and disposal. Excavation was rejected because it would have been cost prohibitive due to the random distribution of the contaminated soil. In-situ Bioremediation was selected as the only alternative which could successfully treat all the contaminated soils. This paper focuses on how KEMRON solved four major problems which would have prevented a successful remediation project. These problems were: soil compaction, random distribution of contaminated soils, potential free product, and extremely high levels of dissolved iron in the groundwater.

  18. Toxic effects of phenol on grey mullet, Mugil auratus Risso

    SciTech Connect

    Krajnovic-Ozretic, M.; Ozretic, B.

    1988-01-01

    Phenolic compounds are frequently found as contaminants in surface waters, including marine coastal waters. Phenols are generally classified as nonspecific metabolic inhibitors, and the main toxic effects are manifested on the nervous system due to the dissolution of lipids, whereas in the circulatory system phenols act as hemolysing agents of the erythrocytes. Data about sublethal effects of phenol, particularly to marine organisms are rather scarce. In several fresh water fish species exposed to phenol, the number of erythrocytes and the amount of serum proteins were decreased while lesion of gill filaments with edema and blood infiltration with degenerative changes in liver were also observed. These investigations concerned the identification of some physiological and biochemical changes in mullet blood as a consequence of exposure to phenol and some observations about the behavior and gross pathology of poisoned fish were also made.

  19. Enhanced bioremediation of petroleum contaminated soils with higher plants

    SciTech Connect

    Schwab, A.P.; Banks, M.K.

    1996-10-01

    Introduction of higher plants into a bioremediation system can enhance degradation of total petroleum hydrocarbons and target compounds, particularly relatively immobile and recalcitrant organic molecules. Over the past several years, an interdisciplinary team of civil engineers, chemical engineers, soil chemists, soil microbiologists, and plant scientists at Kansas State University have been studying phytoremediation systems. Greenhouse experiments have focused on selecting plants that are most adapted to degrading target compounds and to surviving in soils highly contaminated with petroleum hydrocarbons. Plant species do not seem to differ in their ability to aid in the decomposition of pyrene and anthracene, but benzo[a]pyrene is much more difficult to degrade. Most species are ineffective in enhancing the degradation of benzo[a]pyrene. Four field studies have been initiated in California, Texas, New Jersey, and Virginia to test some of our greenhouse observations.

  20. Detection of phenols using engineered bacteria

    DOEpatents

    Wise, Arlene A.; Kuske, Cheryl R.; Terwilliger, Thomas C.

    2004-08-10

    Detection of phenols using engineered bacteria. A biosensor can be created by placing a reporter gene under control of an inducible promoter. The reporter gene produces a signal when a cognate transcriptional activator senses the inducing chemical. Creation of bacterial biosensors is currently restricted by limited knowledge of the genetic systems of bacteria that catabolize xenobiotics. By using mutagenic PCR to change the chemical specificity of the Pseudomonas species CF600 DmpR protein, the potential for engineering novel biosensors for detection of phenols has been demonstrated. DmpR, a well-characterized transcriptional activator of the P. CF600's dmp operon mediates growth on simple phenols. Transcription from Po, the promoter heading the dmp operon, is activated when the sensor domain of DmpR interacts with phenol and mono-substituted phenols. By altering the sensor domain of the DmpR, a group of DmpR derivatives that activate transcription of a Po-lacZ fusion in response to eight of the EPA's eleven priority pollutant phenols has been created. The assays and the sensor domain mutations that alter the chemical specificity of DmpR is described.

  1. Detection of phenols using engineered bacteria

    DOEpatents

    Wise, Arlene A.; Kuske, Cheryl R.; Terwilliger, Thomas C.

    2007-12-04

    Detection of phenols using engineered bacteria. A biosensor can be created by placing a reporter gene under control of an inducible promoter. The reporter gene produces a signal when a cognate transcriptional activator senses the inducing chemical. Creation of bacterial biosensors is currently restricted by limited knowledge of the genetic systems of bacteria that catabolize xenobiotics. By using mutagenic PCR to change the chemical specificity of the Pseudomonas species CF600 DmpR protein, the potential for engineering novel biosensors for detection of phenols has been demonstrated. DmpR, a well-characterized transcriptional activator of the P. CF600's dmp operon mediates growth on simple phenols. Transcription from Po, the promoter heading the dmp operon, is activated when the sensor domain of DmpR interacts with phenol and mono-substituted phenols. By altering the sensor domain of the DmpR, a group of DmpR derivatives that activate transcription of a Po-lacZ fusion in response to eight of the EPA's eleven priority pollutant phenols has been created. The assays and the sensor domain mutations that alter the chemical specificity of DmpR is described.

  2. Synthesis of improved phenolic resins

    NASA Technical Reports Server (NTRS)

    Delano, C. B.; Mcleod, A. H.

    1979-01-01

    Twenty seven addition cured phenolic resin compositions were prepared and tested for their ability to give char residues comparable to state-of-the-art phenolic resins. Cyanate, epoxy, allyl, acrylate, methacrylate and ethynyl derivatized phenolic oligomers were investigated. The novolac-cyanate and propargyl-novolac resins provided anaerobic char yields at 800 C of 58 percent. A 59 percent char yield was obtained from modified epoxy novolacs. A phosphonitrilic derivative was found to be effective as an additive for increasing char yields. The novolac-cyanate, epoxy-novolac and methacrylate-epoxy-novolac systems were investigated as composite matrices with Thornel 300 graphite fiber. All three resins showed good potential as composite matrices. The free radical cured methacrylate-epoxy-novolac graphite composite provided short beam shear strengths at room temperature of 93.3 MPa (13.5 ksi). The novolac-cyanate graphite composite produced a short beam shear strength of 74 MPa (10.7 ksi) and flexural strength of 1302 MPa (189 ksi) at 177 C. Air heat aging of the novolac-cyanate and epoxy novolac based composites for 12 weeks at 204 C showed good property retention.

  3. Mass spectrometric behavior of phenolic acids standards and their analysis in the plant samples with LC/ESI/MS system.

    PubMed

    Ostrowski, Wojciech; Wojakowska, Anna; Grajzer, Magdalena; Stobiecki, Maciej

    2014-09-15

    Liquid chromatography coupled to mass spectrometry (MS) with electrospray ionization (ESI) is one of analytical techniques to obtain accurate results of low molecular weight aromatic compounds in biological samples of different origin. The interpretations of mass spectra of these aromatic compounds in the negative spectra registered in the full scan MS mode may be uneasy due to presence of deprotonated molecules [M-H](-) from different co-eluting entities, fragment ions created after the break-up of precursor ions and also ions representing modified molecules clusters. Thus, the first aim of this study was to evaluate general parameters during analysis performed in the full scan MS or MS/MS mode. Secondly, to set general fragmentation rules for aromatic compounds and entities in a complex biological matrix. We established that different groups of low molecular weight phenolic acids form unique adduct ions and additionally registration LC/MS/MS spectra with two different collision energies may allow for differentiating isomeric or isobaric molecules. These findings together with some general fragmentation rules can facilitate identifications of aromatic acids as we outlined in the sample of cold-pressed rose-hip oil and lupine leaves extract. PMID:25063924

  4. BIOREMEDIATION FIELD EVALUATION - HILL AIR FORCE BASE, UTAH

    EPA Science Inventory

    In 1990, the U.S. Environmental Protection Agency (EPA) established the Bioremediation Field Initiative as part of its overall strategy to increase the use of bioremediation to treat hazardous wastes at Comprehensive Environmental Response, Compensation, and Liabil- ity Act (C...

  5. MUTAGENICITY OF PAH-CONTAMINATED SOILS DURING BIOREMEDIATION

    EPA Science Inventory

    Bioremediation of contaminated soils is considered an effective method for reducing potential health hazards. Although it is assumed that (bio)remediation is a detoxifying process, degradation products of compounds such as polycyclic aromatic compounds (PACs) can be more toxic th...

  6. In situ and on-site bioremediation. Volume 2

    SciTech Connect

    Alleman, B.C.; Leeson, A.

    1997-11-01

    Collected in Volume 2 are articles on the bioremediation of media contaminated by polycyclic aromatic hydrocarbons (PAHs), PCBs and chlorinated aromatics, explosives and nitroaromatics, pesticides and herbicides, and other recalcitrant compounds. The technologies discussed include intrinsic remediation/natural attenuation, fungal technologies, application of surfactants, composting, and landfarming. This volume also contains articles on field methods and process monitoring to support bioremediation applications.

  7. BIOREMEDIATION OF PETROLEUM HYDROCARBON CONTAMINANTS IN MARINE HABITATS

    EPA Science Inventory

    Bioremediation is being increasingly seen as an effective environmentally benign treatment for shorelines contaminated as a result of marine oil spills. Despite a relatively long history of research on oil-spill bioremediation, it remains an essentially empirical technology and m...

  8. Soil Bioremediation Strategies Based on the Use of Fungal Enzymes

    NASA Astrophysics Data System (ADS)

    Mougin, Christian; Boukcim, Hassan; Jolivalt, Claude

    The pollution of soil due to chemical compounds is an important problem worldwide. For that reason, the development of bioremediation processes remains an important challenge. In that context, filamentous fungi and their enzymatic systems appear to be potent tools to decrease the levels of contaminants in soils, by contaminant degradation or stabilisation. The structures and modes of action of selected fungal enzymes, namely peroxidases and laccases, have been extensively studied and are now well-known. Nevertheless, some improvement of their catalytic characteristics can be attempted through genetic engineering, in order to develop specific properties. In addition, some research is still needed to overcome several of their limitations for their efficient use in soils.

  9. Enhanced bioremediation of oil spills in the sea.

    PubMed

    Ron, Eliora Z; Rosenberg, Eugene

    2014-06-01

    Hydrocarbon-degrading bacteria are ubiquitous in the sea, including hydrocarbonoclastic bacteria that utilize hydrocarbons almost exclusively as carbon and energy sources. However, the rates at which they naturally degrade petroleum following an oil spill appear to be too slow to prevent oil from reaching the shore and causing environmental damage, as has been documented in the Exxon Valdez and Gulf of Mexico disasters. Unfortunately, there is, at present, no experimentally demonstrated methodology for accelerating the degradation of hydrocarbons in the sea. The rate-limiting factor for petroleum degradation in the sea is availability of nitrogen and phosphorus. Oleophilic fertilizers, such as Inipol EAP 22 and urea-formaldehyde polymers, have stimulated hydrocarbon degradation on shorelines but are less effective in open systems. We suggest uric acid as a potentially useful fertilizer enhancing bioremediation at sea. PMID:24657912

  10. Attenuation of chromium toxicity by bioremediation technology.

    PubMed

    Mohanty, Monalisa; Patra, Hemanta Kumar

    2011-01-01

    Chromium is an important toxic environmental pollutant. Chromium pollution results largely from industrial activities, but other natural and anthropogenic sources also contribute to the problem. Plants that are exposed to environmental contamination by chromium are affected in diverse ways, including a tendency to suffer metabolic stress. The stress imposed by Cr exposure also extends to oxidative metabolic stress in plants that leads to the generation of active toxic oxygen free radicals. Such active free radicals degrade essential biomolecules and distort plant biological membranes. In this chapter, we describe sources of environmental chromium contamination, and provide information about the toxic impact of chromium on plant growth and metabolism. In addition, we address different phytoremediation processes that are being studied for use worldwide, in contaminated regions, to address and mitigate Cr pollution. There has been a long history of attempts to successfully mitigate the toxic effects of chromium-contaminated soil on plants and other organisms. One common approach, the shifting of polluted soil to landfills, is expensive and imposes environmental risks and health hazards of its own. Therefore, alternative eco-friendly bioremediation approaches are much in demand for cleaning chromium-polluted areas. To achieve its cleaning effects, bioremediation utilizes living organisms (bacteria, algae, fungi, and plants) that are capable of absorbing and processing chromium residues in ways which amend or eliminate it. Phytoremediation (bioremediation with plants) techniques are increasingly being used to reduce heavy metal contamination and to minimize the hazards of heavy metal toxicity. To achieve this, several processes, viz., rhizofiltration, phytoextraction, phytodetoxification, phytostabilization, and phytovolatilization, have been developed and are showing utility in practice, or promise. Sources of new native hyperaccumulator plants for use at contaminated

  11. Bioremediation of Mixtures of High Molecular Weight Polycyclic Aromatic Hydrocarbons

    NASA Astrophysics Data System (ADS)

    Xu, H.; Wu, J.; Shi, X.; Sun, Y.

    2014-12-01

    Although bioremediation has been considered as one of the most promising means to remove polycyclic aromatic hydrocarbons (PAHs) from polluted environments, the efficacy of PAHs bioremediation still remains challenged, especially for high molecular weight PAHs (HMW PAHs) and their mixtures. This study was focused on (a) isolation and characterization of pure strain and mixed microbial communities able to degrade HMW PAHs and (b) further evaluation of the ability of the isolated microbes to degrade HMW PAHs mixtures in the absence and presence of indigenous flora. Fluoranthene, benzo[b]fluoranthene and pyrene were selected as the representative HMW PAHs in this study. A pure bacterial strain, identified as Herbaspirillum chlorophenolicum FA1, was isolated from activated sludge. A mixed bacterial community designated as consortium-4 was isolated from petroleum contaminated soils, containing Pseudomonas sp. FbP1、Enterobacter sp. FbP2、Hydrogenophaga sp. FbP3 and Luteolibacter pohnpeiensis. FbP4. To our knowledge, this is the first study to demonstrate that bacterial strains of Herbaspirillum chlorophenolicum FA1 and Luteolibacter pohnpeiensis. FbP4 can also degrade fluoranthene, benzo[b]fluoranthene and pyrene. Experiment results showed that both strain FA1 and consortium-4 could degrade fluoranthene, benzo[b]fluoranthene and pyrene within a wide range of temperature, pH and initial PAHs concentration. Degradation of HMW PAHs mixtures (binary and ternary) demonstrated the interactive effects that can alter the rate and extent of biodegradation within a mixture. The presence of indigenous flora was found to either increase or decrease the degradation of HMW PAHs, suggesting possible synergistic or competition effects. Biodegradation kinetics of HMW PAHs for sole substrates, binary and ternary systems was evaluated, with the purpose to better characterize and compare the biodegradation process of individual HMW PAH and mixtures of HMW PAHs. Results of this study

  12. Utilization of microbial biofilms as monitors of bioremediation

    SciTech Connect

    Peacock, Aaron D.; IstokD., Jonathan; Krumholz, Lee R.; Geyer, Roland; Kinsall, Barry Lee; Watson, David B; Sublette, K.; White, David C.

    2004-03-01

    A down-well aquifer microbial sampling system was developed using glass wool or Bio-Sep beads as a solid-phase support matrix. Here we describe the use of these devices to monitor the groundwater microbial community dynamics during field bioremediation experiments at the U.S. Department of Energy Natural and Accelerated Bioremediation Research Programs Field Research Center at the Oak Ridge National Laboratory. During the 6-week deployment, microbial biofilms colonized glass wool and bead internal surfaces. Changes in viable biomass, community composition, metabolic status, and respiratory state were reflected in sampler composition, type of donor, and groundwater pH. Biofilms that formed on Bio-Sep beads had 2-13 times greater viable biomass; however, the bead communities were less metabolically active [higher cyclopropane/monoenoic phospholipid fatty acid (PLFA) ratios] and had a lower aerobic respiratory state (lower total respiratory quinone/PLFA ratio and ubiquinone/menaquinone ratio) than the biofilms formed on glass wool. Anaerobic growth in these systems was characterized by plasmalogen phospholipids and was greater in the wells that received electron donor additions. Partial 16S rDNA sequences indicated that Geobacter and nitrate-reducing organisms were induced by the acetate, ethanol, or glucose additions. DNA and lipid biomarkers were extracted and recovered without the complications that commonly plague sediment samples due to the presence of clay or dissolved organic matter. Although microbial community composition in the groundwater or adjacent sediments may differ from those formed on down-well biofilm samplers, the metabolic activity responses of the biofilms to modifications in groundwater geochemistry record the responses of the microbial community to biostimulation while providing integrative sampling and ease of recovery for biomarker analysis.

  13. Bioremediation of nitroaromatic and haloaromatic compounds

    SciTech Connect

    Alleman, B.C.; Leeson, A.

    1999-10-01

    Sites contaminated with explosive compounds, pesticides, herbicides, PCBs, and other aromatic compounds present formidable technical, regulatory, and financial challenges. The application of bioremediation technologies at such sites offers the promise of cost-effective site remediation that can serve as a key component of a well-formulated strategy for achieving site closure. This volume presents the results of bench-, pilot-, and field-scale projects focused on the use of biological approaches to remediate problem compounds, such as RDX, HMX, TNT, DDT, 2,4-D, nitro- and chlorobenzenes, nitroaniline, chloroaniline, hexachlorobenzene, PCPs, PCBs, and dichlorophenol in soils and groundwater.

  14. Bioremediation of uranium contaminated Fernald soils

    SciTech Connect

    Delwiche, M.E.; Wey, J.E.; Torma, A.E.

    1994-12-31

    This study investigated the use of microbial bioleaching for removal of uranium from contaminated soils. The ability of bacteria to assist in oxidation and solubilization of uranium was compared to the ability of fungi to produce complexing compounds which have the same effect. Biosorption of uranium by fungi was also measured. Soil samples were examined for changes in mineralogical properties due to these processes. On the basis of these laboratory scale studies a generalized flow sheet is proposed for bioremediation of contaminated Fernald soils.

  15. Vapor phase oxidation of benzoic acid to phenol over a novel catalyst system consisting of NiO and NiFe{sub 2}O{sub 4}

    SciTech Connect

    Miki, Jun; Asanuma, Minoru; Tachibana, Yakudo

    1995-02-01

    NiO and Fe{sub 2}O{sub 3} were found to show the catalytic activities for the vapor phase oxidation of benzoic acid to form phenol. Furthermore, the enhancement of the activity and phenol selectivity were achieved by combined Ni and Fe components prepared by precipitation. The calcination temperature and the atomic ratio of Ni to Fe were found to be important for the enhancement of activity. The homogeneous distribution profile of NiO and NiFe{sub 2}O{sub 4} on the surface and in the bulk of the catalyst is essential for the optimization of phenol formation. 32 refs., 7 figs., 4 tabs.

  16. THERMOPHILIC ANAEROBIC BIODEGRADATION OF PHENOLICS

    EPA Science Inventory

    The report gives results of a series of anaerobic microbial acclimation and treatment performance tests with synthetic phenolic substrates. The research is a feasibility level assessment of substituting anaerobic biodegradation of phenolics for solvent extraction. The tests showe...

  17. Bioremediation of organic solvents in ground water: A case study--Grandview, Missouri

    SciTech Connect

    Humenik, J.A. )

    1993-10-01

    Organic solvents leaking from underground storage tanks or from spillage pose a serious threat to ground-water quality. Chemicals such as styrene, ethylbenzene, toluene, and methyl-methacrylate are commonly associated with the manufacturing of plastics and fiberglass. After pump-and-treat operations were unsuccessful in remediating ground water contaminated with ethylbenzene and styrene resulting from leaking underground chemical storage tanks, bioremediation was implemented to degrade the contaminants to the Missouri Department of Natural Resources target cleanup limits. Due to low permeability clays and anaerobic subsurface conditions, the bioremediation design consisted of a ground-water recovery system, an aboveground bioreactor to treat ground water, and a recharge network to introduce acclimated microbes, nutrients, and oxygen to the subsurface. Commercially prepared microbial strains and nutrients were utilized for the close-loop system, as insufficient indigenous microbes and nutrients were present in subsurface matrix.

  18. Pyrolysis of phenolic impregnated carbon ablator (PICA).

    PubMed

    Bessire, Brody K; Lahankar, Sridhar A; Minton, Timothy K

    2015-01-28

    Molar yields of the pyrolysis products of thermal protection systems (TPSs) are needed in order to improve high fidelity material response models. The volatile chemical species evolved during the pyrolysis of a TPS composite, phenolic impregnated carbon ablator (PICA), have been probed in situ by mass spectrometry in the temperature range 100 to 935 °C. The relative molar yields of the desorbing species as a function of temperature were derived by fitting the mass spectra, and the observed trends are interpreted in light of the results of earlier mechanistic studies on the pyrolysis of phenolic resins. The temperature-dependent product evolution was consistent with earlier descriptions of three stages of pyrolysis, with each stage corresponding to a temperature range. The two main products observed were H2O and CO, with their maximum yields occurring at ∼350 °C and ∼450 °C, respectively. Other significant products were CH4, CO2, and phenol and its methylated derivatives; these products tended to desorb concurrently with H2O and CO, over the range from about 200 to 600 °C. H2 is presumed to be the main product, especially at the highest pyrolysis temperatures used, but the relative molar yield of H2 was not quantified. The observation of a much higher yield of CO than CH4 suggests the presence of significant hydroxyl group substitution on phenol prior to the synthesis of the phenolic resin used in PICA. The detection of CH4 in combination with the methylated derivatives of phenol suggests that the phenol also has some degree of methyl substitution. The methodology developed is suitable for real-time measurements of PICA pyrolysis and should lend itself well to the validation of nonequilibrium models whose aim is to simulate the response of TPS materials during atmospheric entry of spacecraft. PMID:25490209

  19. The Kwajalein bioremediation demonstration: Final technical report

    SciTech Connect

    Walker, J.R. Jr.; Walker, A.B.

    1994-12-01

    The US Army Kwajalein Atoll (USAKA) Base, located in the Republic of the Marshall Islands (RMI) in the east-central Pacific Ocean, has significant petroleum hydrocarbon contamination resulting from years of military activities. Because of its remoteness, the lack of on-site sophisticated remediation or waste disposal facilities, the amenability of petroleum hydrocarbons to biodegradation, and the year-round temperature favorable for microbial activity, USAKA requested, through the Hazardous Waste Remedial Actions Program (HAZWRAP), that a project be conducted to evaluate the feasibility of using bioremediation for environmental restoration of contaminated sites within the atoll. The project was conducted in four distinct phases: (1) initial site characterization and on-site biotreatability studies, (2) selection of the demonstration area and collection of soil columns, (3) laboratory column biotreatability studies, and (4) an on-site bioremediation demonstration. The results of phases (1) and (3) have been detailed in previous reports. This report summarizes the results of phases (1) and (3) and presents phases (2) and (4) in detail.

  20. Bioremediation of chlorinated solvents and diesel soils

    SciTech Connect

    Huismann, S.S.; Peterson, M.A.; Jardine, R.J.

    1995-11-01

    The US Army, in a cooperative effort with the Tennessee Valley Authority (TVA) and its cooperator, ENSR, performed an innovative enhanced bioremediation project at Fort Gillem in Atlanta, Georgia. The objective of the project was to remediate six hundred cubic yards of soil affected by a mixture of chlorinated compounds and petroleum hydrocarbons which posed a threat to uppermost groundwater and private drinking water wells. ENSR completed a demonstration project to measure the effects of bioremediation on both chlorinated compounds (primarily TCE) and petroleum hydrocarbons ({number_sign}2 diesel). Contaminated soil was placed on top of a bermed polyethylene liner to construct an ex-situ biovault. Nutrients were added to the soil as it was loaded onto the liner. Contaminated soil was also used to construct a control vault. A methane barrier cover was placed over both piles. The cover was designed to prevent short circuiting of induced airflow in and around the enhanced pile, and to prevent the release of fugitive emissions from either pile.

  1. Healthy environments for healthy people: bioremediation today and tomorrow.

    PubMed Central

    Bonaventura, C; Johnson, F M

    1997-01-01

    Increases in environmental contamination lead to a progressive deterioration of environmental quality. This condition challenges our global society to find effective measures of remediation to reverse the negative conditions that severely threaten human and environmental health. We discuss the progress being made toward this goal through application of bioremediation techniques. Bioremediation generally utilizes microbes (bacteria, fungi, yeast, and algae), although higher plants are used in some applications. New bioremediation approaches are emerging based on advances in molecular biology and process engineering. Bioremediation continues to be the favored approach for processing biological wastes and avoiding microbial pathogenesis. Bioremediation may also play an increasing role in concentrating metals and radioactive materials to avoid toxicity or to recover metals for reuse. Microbes can biodegrade organic chemicals; purposeful enhancement of this natural process can aid in pollutant degradation and waste-site cleanup operations. Recently developed rapid-screening assays can identify organisms capable of degrading specific wastes and new gene-probe methods can ascertain their abundance at specific sites. New tools and techniques for use of bioremediation in situ, in biofilters, and in bioreactors are contributing to the rapid growth of this field. Bioremediation has already proven itself to be a cost-effective and beneficial addition to chemical and physical methods of managing wastes and environmental pollutants. We anticipate that it will play an increasingly important role as a result of new and emerging techniques and processes. Images Figure 3. PMID:9114274

  2. Healthy environments for healthy people: Bioremediation today and tomorrow

    SciTech Connect

    Bonaventura, C.; Johnson, F.M.

    1997-02-01

    Increases in environmental contamination lead to a progressive deterioration of environmental quality. This condition challenges our global society to find effective measures of remediation to reverse the negative conditions that severely threaten human and environmental health. We discuss the progress being made toward this goal through application of bioremediation techniques. Bioremediation generally utilizes microbes (bacteria, fungi, yeast, and algae), although higher plants are used in some applications. New bioremediation approaches are emerging based on advances in molecular biology and process engineering. Bioremediation continues to be the favored approach for processing biological wastes and avoiding microbial pathogenesis. Bioremediation may also play an increasing role in concentrating metals and radioactive materials to avoid toxicity or to recover metals for reuse. Microbes can biodegrade organic chemicals; purposeful enhancement of this natural process can aid in pollutant degradation and waste-site cleanup operations. Recently developed rapid-screening assays can identify organisms capable of degrading specific wastes and new gene-probe methods can ascertain their abundance at specific sites. New tools and techniques for use of bioremediation in situ, in biofilters, and in bioreactors are contributing to the rapid growth of this field. Bioremediation has already proven itself to be a cost-effective and beneficial addition to chemical and physical methods of managing wastes and environmental pollutants. We anticipate that it will play an increasingly important role as a result of new and emerging techniques and processes. 140 refs., 4 figs., 1 tab.

  3. Method for enhanced longevity of in situ microbial filter used for bioremediation

    DOEpatents

    Carman, M.L.; Taylor, R.T.

    1999-03-30

    An improved method is disclosed for in situ microbial filter bioremediation having increasingly operational longevity of an in situ microbial filter emplaced into an aquifer. A method is presented for generating a microbial filter of sufficient catalytic density and thickness, which has increased replenishment interval, improved bacteria attachment and detachment characteristics and the endogenous stability under in situ conditions. A system is also disclosed for in situ field water remediation. 31 figs.

  4. Induction of NAD(P)H:quinone reductase in murine hepatoma cells by phenolic antioxidants, azo dyes, and other chemoprotectors: a model system for the study of anticarcinogens

    SciTech Connect

    De Long, M.J.; Prochaska, H.J.; Talalay, P.

    1986-02-01

    Exposure of murine hepatoma (Hepa 1c1c7) cells to a variety of chemical agents known to protect animals against the neoplastic, mutagenic, and other toxic effects of chemical carcinogens results in dose- and time-dependent inductions of NAD(P)H:quinone reductase (EC 1.6.99.2). This enzyme protects against quinone toxicity by promoting obligatory two-electron reductions that divert quinones from oxidative cycling or direct interactions with critical nucleophiles. Quinone reductase levels are stable in culture, are easily measured, and are useful markers for the inductive effects of chemoprotective agents. The Hepa 1c1c7 system responds to chemoprotective compounds such as phenolic antioxidants /e.g., BHA (3(2)-tert-butyl-4-hydroxyanisole), BHT (3,5-di-tert-butyl-4-hydroxytoluene), and tert-butylhydroquinone/, lipophilic azo dyes belonging to the 1,1'-azonaphthalene, Sudan I (1-phenylazo-2-naphthol), and Sudan III (1-(4-phenylazophenylazo)-2-naphthol) families, polycyclic aromatic hydrocarbons, coumarin and various other lactones, flavonoids, and certain sulfur compounds (e.g., benzylisothiocyanate, dithiolthiones, and dithiocarbamates), all of which are recognized enzyme inducers and chemoprotectors in vivo. Quinone reductase induction in Hepa 1c1c7 cells therefore provides a simple, versatile, and reliable system for the evaluation of the potency, kinetics, and mechanism of action of anticarcinogens.

  5. Phenol and phenolics from lignocellulosic biomass by catalytic microwave pyrolysis

    SciTech Connect

    Bu, Quan; Lei, Hanwu; Ren, Shoujie; Wang, Lu; Holladay, Johnathan E.; Zhang, Qin; Tang, Juming; Ruan, Roger

    2011-07-01

    Catalytic microwave pyrolysis of biomass using activated carbon was investigated to determine the effects of pyrolytic conditions on the yields of phenol and phenolics. The high concentrations of phenol (38.9%) and phenolics (66.9%) were obtained at the temperature of 589 K, catalyst-to-biomass ratio of 3:1 and retention time of 8 min. The increase of phenol and its derivatives compared to pyrolysis without catalysts has a close relationship with the decomposition of lignin under the performance of activated carbon. The concentration of esters was also increased using activated carbon as a catalyst. The high content of phenols obtained in this study can be used either directly as fuel after upgrading or as feedstock of biobased phenols for chemical industry.

  6. Hydraulic control for manipulating subsurface conditions for in situ experiments of uranium(VI) bioremediation

    NASA Astrophysics Data System (ADS)

    Kitanidis, P.; Luo, J.; Wu, W.; Carley, J.; Mehlhorn, T.; Watson, D.; Criddle, C.; Jardine, P.

    2007-12-01

    A field test on in-situ subsurface bioremediation of uranium (VI) is underway at the Y-12 National Security Complex in the Oak Ridge Reservation, Oak Ridge, TN. A four-well system, including two downgradient extraction and two upgradient injection wells were installed to create an inner cell, which functioned as the treatment zone, nested within an outer cell, which protected the inner cell from the influence of regional flow. The proposed four- well system has several advantages in the subsurface flow field manipulation: (1) the recirculation ratio within the nested inner cell is less sensitive to the regional flow direction; (2) a transitional recirculation zone between the inner and outer cells can capture flow leakage from the inner cell, minimizing the release of untreated contaminants; (3) the size of the recirculation zone and residence times can be better controlled within the inner cell by changing the pumping rates. A three-phase remediation strategy was applied in this experiment. It included first removing nitrate prior to stimulation of U(VI) reduction, then adjusting the pH to levels favorable for activity of U(VI)-reducing bacteria, i.e., to about neutral values, and finally adding electron donor to the in-situ reactor to foster reduction and immobilization of U(VI). Tracer tests and bioremediation experiments demonstrated that the designed multiple-well system and the experimental strategy were successful in creating favorable subsurface chemical and biological conditions for uranium bioremediation.

  7. Bioremediation of hazardous wastes. Research, development, and field evaluations, 1995

    SciTech Connect

    Kremer, F.

    1995-09-01

    The U.S. Environmental Protection Agency`s (EPA`s) Office of Research and Development (ORD) hosted the eighth annual Symposium on Bioremediation of Hazardous Wastes: Research, Development, and Field Evaluations in Rye Brook, New York, August 8-10, 1995. In this document, abstracts of paper and poster presentations from the symposium are organized within five key research and program areas: Bioremediation Field Initiative; Field research; Performance evaluation; Pilot-scale research; and Process research. The last section of the document includes abstracts of presentations on bioremediation research performed as part of the Hazardous Substance Research Center (HSRC) program.

  8. Preconversion catalytic deoxygenation of phenolic functional groups

    SciTech Connect

    Kubiak, C.P.

    1991-01-01

    The deoxygenation of phenols is a conceptually simple, but unusually difficult chemical transformation to achieve. Aryl carbon-oxygen bond cleavage is a chemical transformation of importance in coal liquefaction and the upgrading of coal liquids as well as in the synthesis of natural products. This proposed research offers the possibility of effecting the selective catalytic deoxygenation of phenolic functional groups using CO. A program of research for the catalytic deoxygenation of phenols, via a low energy mechanistic pathway that is based on the use of the CO/CO{sub 2} couple to remove phenolic oxygen atoms, is underway. We are focusing on systems which have significant promise as catalysts: Ir(triphos)OPh, (Pt(triphos)OPh){sup +} and Rh(triphos)OPh. Our studies of phenol deoxygenation focus on monitoring the reactions for the elementary processes upon which catalytic activity will depend: CO insertion into M-OPh bonds, CO{sub 2} elimination from aryloxy carbonyls {l brace}M-C(O)-O-Ph{r brace}, followed by formation of a coordinated benzyne intermediate.

  9. Laboratory-scale in situ bioremediation in heterogeneous porous media: Biokinetics-limited scenario

    NASA Astrophysics Data System (ADS)

    Song, Xin; Hong, Eunyoung; Seagren, Eric A.

    2014-03-01

    Subsurface heterogeneities influence interfacial mass-transfer processes and affect the application of in situ bioremediation by impacting the availability of substrates to the microorganisms. However, for difficult-to-degrade compounds, and/or cases with inhibitory biodegradation conditions, slow biokinetics may also limit the overall bioremediation rate, or be as limiting as mass-transfer processes. In this work, a quantitative framework based on a set of dimensionless coefficients was used to capture the effects of the competing interfacial and biokinetic processes and define the overall rate-limiting process. An integrated numerical modeling and experimental approach was used to evaluate application of the quantitative framework for a scenario in which slow-biokinetics limited the overall bioremediation rate of a polycyclic aromatic hydrocarbon (naphthalene). Numerical modeling was conducted to simulate the groundwater flow and naphthalene transport and verify the system parameters, which were used in the quantitative framework application. The experiments examined the movement and biodegradation of naphthalene in a saturated, heterogeneous intermediate-scale flow cell with two layers of contrasting hydraulic conductivities. These experiments were conducted in two phases: Phase I, simulating an inhibited slow biodegradation; and Phase II, simulating an engineered bioremediation, with system perturbations selected to enhance the slow biodegradation rate. In Phase II, two engineered perturbations to the system were selected to examine their ability to enhance in situ biodegradation. In the first perturbation, nitrogen and phosphorus in excess of the required stoichiometric amounts were spiked into the influent solution to mimic a common remedial action taken in the field. The results showed that this perturbation had a moderate positive impact, consistent with slow biokinetics being the overall rate-limiting process. However, the second perturbation, which was to

  10. Laboratory-scale in situ bioremediation in heterogeneous porous media: biokinetics-limited scenario.

    PubMed

    Song, Xin; Hong, Eunyoung; Seagren, Eric A

    2014-03-01

    Subsurface heterogeneities influence interfacial mass-transfer processes and affect the application of in situ bioremediation by impacting the availability of substrates to the microorganisms. However, for difficult-to-degrade compounds, and/or cases with inhibitory biodegradation conditions, slow biokinetics may also limit the overall bioremediation rate, or be as limiting as mass-transfer processes. In this work, a quantitative framework based on a set of dimensionless coefficients was used to capture the effects of the competing interfacial and biokinetic processes and define the overall rate-limiting process. An integrated numerical modeling and experimental approach was used to evaluate application of the quantitative framework for a scenario in which slow-biokinetics limited the overall bioremediation rate of a polycyclic aromatic hydrocarbon (naphthalene). Numerical modeling was conducted to simulate the groundwater flow and naphthalene transport and verify the system parameters, which were used in the quantitative framework application. The experiments examined the movement and biodegradation of naphthalene in a saturated, heterogeneous intermediate-scale flow cell with two layers of contrasting hydraulic conductivities. These experiments were conducted in two phases: Phase I, simulating an inhibited slow biodegradation; and Phase II, simulating an engineered bioremediation, with system perturbations selected to enhance the slow biodegradation rate. In Phase II, two engineered perturbations to the system were selected to examine their ability to enhance in situ biodegradation. In the first perturbation, nitrogen and phosphorus in excess of the required stoichiometric amounts were spiked into the influent solution to mimic a common remedial action taken in the field. The results showed that this perturbation had a moderate positive impact, consistent with slow biokinetics being the overall rate-limiting process. However, the second perturbation, which was to