WorldWideScience

Sample records for bioremediation spatial similarities

  1. Bacterial Community Succession During in situ Uranium Bioremediation: Spatial Similarities Along Controlled Flow Paths

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Chiachi; Wu, Weimin; Gentry, Terry J.; Carley, Jack; Corbin, Gail A.; Carroll, Sue L.; Watson, David B.; Jardine, Phil M.; Zhou, Jizhong; Criddle, Craig S.; Fields, Matthew W.

    2009-05-22

    Bacterial community succession was investigated in a field-scale subsurface reactor formed by a series of wells that received weekly ethanol additions to re-circulating groundwater. Ethanol additions stimulated denitrification, metal reduction, sulfate reduction, and U(VI) reduction to sparingly soluble U(IV). Clone libraries of SSU rRNA gene sequences from groundwater samples enabled tracking of spatial and temporal changes over a 1.5 y period. Analyses showed that the communities changed in a manner consistent with geochemical variations that occurred along temporal and spatial scales. Canonical correspondence analysis revealed that the levels of nitrate, uranium, sulfide, sulfate, and ethanol strongly correlated with particular bacterial populations. As sulfate and U(VI) levels declined, sequences representative of sulfate-reducers and metal-reducers were detected at high levels. Ultimately, sequences associated with sulfate-reducing populations predominated, and sulfate levels declined as U(VI) remained at low levels. When engineering controls were compared to the population variation via canonical ordination, changes could be related to dissolved oxygen control and ethanol addition. The data also indicated that the indigenous populations responded differently to stimulation for bio-reduction; however, the two bio-stimulated communities became more similar after different transitions in an idiosyncratic manner. The strong associations between particular environmental variables and certain populations provide insight into the establishment of practical and successful remediation strategies in radionuclide-contaminated environments with respect to engineering controls and microbial ecology.

  2. Textual Spatial Cosine Similarity

    OpenAIRE

    Crocetti, Giancarlo

    2015-01-01

    When dealing with document similarity many methods exist today, like cosine similarity. More complex methods are also available based on the semantic analysis of textual information, which are computationally expensive and rarely used in the real time feeding of content as in enterprise-wide search environments. To address these real-time constraints, we developed a new measure of document similarity called Textual Spatial Cosine Similarity, which is able to detect similitude at the semantic ...

  3. Measurement of Similarity for Spatial Directions Between Areal Objects

    Institute of Scientific and Technical Information of China (English)

    DING Hong; GUO Qingsheng; DU Xiaohu

    2004-01-01

    Similarity for spatial directions plays an important role in GIS. In this paper, the conventional approaches are analyzed. Based on raster data areal objects, the authors propose two new methods for measuring similarity among spatial directions. One is to measure the similarity among spatial directions based on the features of raster data and the changes of distances between spatial objects, the other is to measure the similarity among spatial directions according to the variation of each raster cell centroid angle. The two methods overcome the complexity of measuring similarity among spatial directions with direction matrix model and solve the limitation of small changes in direction. The two methods are simple and have broader applicability.

  4. Distance decay of ß-similarity: spatial or ecological barriers?

    Directory of Open Access Journals (Sweden)

    Duccio Rocchini

    2008-01-01

    Full Text Available ß-diversity is defined as the complementarity in species composition between pairs of sites and plays a crucial role in biodiversity management and conservation, since it allows to detect those environmental gradients that functionally act in determining the variation of species composition. From an ecological viewpoint, the decay of ß-similarity principally arises from: (i a decrease in environmental similarity with distance, which inevitably creates a competition among species with different physiological abilities (niche difference model; (ii a spatial configuration which creates spatial barriers and thus isolation among habitats, that influences species and gene movement across landscapes. To date, efforts were made to demonstrate the effect of distance on species similarity. However, few tests have been performed at local scale, i.e. at the community level. The aim of this study is to test the distance decay of ß-similarity hypothesis at local scale (10x10 m plots considering both (i spatial distance between pairs of sites; (ii the ecological distance between pairs of sites, measured as Euclidean distance in vector spaces defined by ecological variables (elevation, aspect, slope, assolation, spectral reflectance considering both the whole multispectral system of a Landsat ETM+ image and the Near Infrared Wavelength, band 4. ß-similarity decay rates at different thresholds (t have been quantified by means of quantile regressions based on exponential models, focusing on the main factors influencing their trends.

  5. Similarity between neonatal profile and socioeconomic index: a spatial approach

    Directory of Open Access Journals (Sweden)

    d'Orsi Eleonora

    2005-01-01

    Full Text Available This study aims to compare neonatal characteristics and socioeconomic conditions in Rio de Janeiro city neighborhoods in order to identify priority areas for intervention. The study design was ecological. Two databases were used: the Brazilian Population Census and the Live Birth Information System, aggregated by neighborhoods. Spatial analysis, multivariate cluster classification, and Moran's I statistics for detection of spatial clustering were used. A similarity index was created to compare socioeconomic clusters with the neonatal profile in each neighborhood. The proportions of Apgar score above 8 and cesarean sections showed positive spatial correlation and high similarity with the socioeconomic index. The proportion of low birth weight infants showed a random spatial distribution, indicating that at this scale of analysis, birth weight is not sufficiently sensitive to discriminate subtler differences among population groups. The observed relationship between the neighborhoods' neonatal profile (particularly Apgar score and mode of delivery and socioeconomic conditions shows evidence of a change in infant health profile, where the possibility for intervention shifts to medical services and the Apgar score assumes growing significance as a risk indicator.

  6. BIOREMEDIATION TRAINING

    Science.gov (United States)

    Bioremediation encompasses a collection of technologies which use microbes to degrade or transform contaminants. Three technologies have an established track record of acceptable performance: aerobic bioventing for fuels; enhanced reductive dechlorination for chlorinated solvent...

  7. Cometabolic bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. Arctic bioremediation

    International Nuclear Information System (INIS)

    Cleanup of oil and diesel spills on gravel pads in the Arctic has typically been accomplished by utilizing a water flushing technique to remove the gross contamination or excavating the spill area and placing the material into a lined pit, or a combination of both. Enhancing the biological degradation of hydrocarbon (bioremediation) by adding nutrients to the spill area has been demonstrated to be an effective cleanup tool in more temperate locations. However, this technique has never been considered for restoration in the Arctic because the process of microbial degradation of hydrocarbon in this area is very slow. The short growing season and apparent lack of nutrients in the gravel pads were thought to be detrimental to using bioremediation to cleanup Arctic oil spills. This paper discusses the potential to utilize bioremediation as an effective method to clean up hydrocarbon spills in the northern latitudes

  9. Arctic bioremediation

    International Nuclear Information System (INIS)

    Cleanup of oil and diesel spills on gravel pads in the Arctic has typically been accomplished by utilizing a water flushing technique to remove the gross contamination or excavating the spill area and placing the material into a lined pit, or a combination of both. This paper discusses the potential to utilize bioremediation as an effective method to clean up hydrocarbon spills in the northern latitudes. Discussed are the results of a laboratory bioremediation study which simulated microbial degradation of hydrocarbon under arctic conditions

  10. A Quantitative Calculation Method of Composite Spatial Direction Similarity Concerning Scale Differences

    Directory of Open Access Journals (Sweden)

    CHEN Zhanlong

    2016-03-01

    Full Text Available This article introduces a new model for direction relations between multiple spatial objects at multiple scales and a corresponding similarity assessment method. The model is an improvement of direction relation matrix, which quantitatively models direction relations on object scale, and by the idea of decomposition and means of the optimum solution of the transportation problem to solve the minimum conversion cost between multiple direction matrices, namely distance between a pair of matrices, thus quantified the difference between a pair of directions, finally obtain the similarity values between arbitrary pairs of multiple spatial objects and compare the results. Experiments on calculating similarity between objects at different scales show that the presented method is efficient, accurate, and capable of obtaining results consistent with human cognition.

  11. Spatial-Temporal Congestion Identification Based on Time Series Similarity Considering Missing Data.

    Science.gov (United States)

    Qi, Hongsheng; Liu, Meiqi; Wang, Dianhai; Chen, Mengwei

    2016-01-01

    Traffic congestion varies spatially and temporally. The observation of the formation, propagation and dispersion of network traffic congestion can lead to insights about the network performance, the bottleneck dynamics etc. While many researchers use the traffic flow data to reconstruct the congestion profile, the data missing problem is bypassed. Current methods either omit the missing data or supplement the missing part by average etc. Great error may be introduced during these processes. Rather than simply discarding the missing data, this research regards the data missing event as a result of either the severe congestion which prevent the floating vehicle from entering the congested area, or a type of feature of the resulting traffic flow time series. Hence a new traffic flow operational index time series similarity measurement is expected to be established as a basis of identifying the dynamic network bottleneck. The method first measures the traffic flow operational similarity between pairs of neighboring links, and then the similarity results are used to cluster the spatial-temporal congestion. In order to get the similarity under missing data condition, the measurement is implemented in a two-stage manner: firstly the so called first order similarity is calculated given that the traffic flow variables are bounded both upside and downside; then the first order similarity is aggregated to generate the second order similarity as the output. We implement the method on part of the real-world road network; the results generated are not only consistent with empirical observation, but also provide useful insights. PMID:27649412

  12. Spatial-Temporal Congestion Identification Based on Time Series Similarity Considering Missing Data.

    Science.gov (United States)

    Qi, Hongsheng; Liu, Meiqi; Wang, Dianhai; Chen, Mengwei

    2016-01-01

    Traffic congestion varies spatially and temporally. The observation of the formation, propagation and dispersion of network traffic congestion can lead to insights about the network performance, the bottleneck dynamics etc. While many researchers use the traffic flow data to reconstruct the congestion profile, the data missing problem is bypassed. Current methods either omit the missing data or supplement the missing part by average etc. Great error may be introduced during these processes. Rather than simply discarding the missing data, this research regards the data missing event as a result of either the severe congestion which prevent the floating vehicle from entering the congested area, or a type of feature of the resulting traffic flow time series. Hence a new traffic flow operational index time series similarity measurement is expected to be established as a basis of identifying the dynamic network bottleneck. The method first measures the traffic flow operational similarity between pairs of neighboring links, and then the similarity results are used to cluster the spatial-temporal congestion. In order to get the similarity under missing data condition, the measurement is implemented in a two-stage manner: firstly the so called first order similarity is calculated given that the traffic flow variables are bounded both upside and downside; then the first order similarity is aggregated to generate the second order similarity as the output. We implement the method on part of the real-world road network; the results generated are not only consistent with empirical observation, but also provide useful insights.

  13. Biodegradation and bioremediation

    DEFF Research Database (Denmark)

    Albrechtsen, H.-J.

    1996-01-01

    Anmeldelse af Alexander,M.: Biodegradation and bioremediation. Academic Press, Sandiego, USA, 1994......Anmeldelse af Alexander,M.: Biodegradation and bioremediation. Academic Press, Sandiego, USA, 1994...

  14. VERBAL AND SPATIAL WORKING MEMORY LOAD HAVE SIMILARLY MINIMAL EFFECTS ON SPEECH PRODUCTION

    Science.gov (United States)

    Lee, Ogyoung; Redford, Melissa A.

    2015-01-01

    The goal of the present study was to test the effects of working memory on speech production. Twenty American-English speaking adults produced syntactically complex sentences in tasks that taxed either verbal or spatial working memory. Sentences spoken under load were produced with more errors, fewer prosodic breaks, and at faster rates than sentence produced in the control conditions, but other acoustic correlates of rhythm and intonation did not change. Verbal and spatial working memory had very similar effects on production, suggesting that the different span tasks used to tax working memory merely shifted speakers’ attention away from the act of speaking. This finding runs contra the hypothesis of incremental phonological/phonetic encoding, which predicts the manipulation of information in verbal working memory during speech production. PMID:26448563

  15. Self-similar spatial structure of a streamer-free nanosecond discharge

    Science.gov (United States)

    Karelin, V. I.; Tren'kin, A. A.

    2008-03-01

    The microstructure of a current channel is experimentally found under the conditions when homogeneous air gaps are subjected to nanosecond voltage pulses in an electric field insufficient for streamer generation. As a possible mechanism of microstructure formation, instability of the ionization process at the avalanche stage leading to the formation of a self-similar spatial structure is considered. The fractal dimension of this structure is determined. In inhomogeneous gaps, the avalanche is shown to be unstable as well. The energy benefit of structuring is considered. It is demonstrated that the microstructure of streamer discharges in homogeneous gaps can also be treated in terms of the model suggested.

  16. The Effect of Similarity: Non-Spatial Features Modulate Obstacle Avoidance

    OpenAIRE

    Rudmer Menger; H Chris Dijkerman; Stefan Van der Stigchel

    2013-01-01

    The introduction of non-target objects into a workspace leads to temporal and spatial adjustments of reaching trajectories towards a target. If the non-target is obstructing the path of the hand towards the target, the reach is adjusted such that collision with the non-target, or obstacle, is avoided. Little is known about the influence of features which are irrelevant for the execution of the movement on avoidance movements, like color similarity between target and non-target objects. In eye...

  17. Spatially pooled contrast responses predict neural and perceptual similarity of naturalistic image categories.

    Directory of Open Access Journals (Sweden)

    Iris I A Groen

    Full Text Available The visual world is complex and continuously changing. Yet, our brain transforms patterns of light falling on our retina into a coherent percept within a few hundred milliseconds. Possibly, low-level neural responses already carry substantial information to facilitate rapid characterization of the visual input. Here, we computationally estimated low-level contrast responses to computer-generated naturalistic images, and tested whether spatial pooling of these responses could predict image similarity at the neural and behavioral level. Using EEG, we show that statistics derived from pooled responses explain a large amount of variance between single-image evoked potentials (ERPs in individual subjects. Dissimilarity analysis on multi-electrode ERPs demonstrated that large differences between images in pooled response statistics are predictive of more dissimilar patterns of evoked activity, whereas images with little difference in statistics give rise to highly similar evoked activity patterns. In a separate behavioral experiment, images with large differences in statistics were judged as different categories, whereas images with little differences were confused. These findings suggest that statistics derived from low-level contrast responses can be extracted in early visual processing and can be relevant for rapid judgment of visual similarity. We compared our results with two other, well- known contrast statistics: Fourier power spectra and higher-order properties of contrast distributions (skewness and kurtosis. Interestingly, whereas these statistics allow for accurate image categorization, they do not predict ERP response patterns or behavioral categorization confusions. These converging computational, neural and behavioral results suggest that statistics of pooled contrast responses contain information that corresponds with perceived visual similarity in a rapid, low-level categorization task.

  18. Similarity between Spatial-temporal Expression Patterning of HOXA11 and Progesterone Receptor in Human Endometrium

    Institute of Scientific and Technical Information of China (English)

    Li-fen WANG; Hong-zhi LUO; Zheng-mei ZHU; Jie-dong WANG

    2003-01-01

    Objective To study HOXAll expression and its correlation with that of the progesterone receptor(PR) gene in human endometriumMethods In situ hybridization and semi-quantitative RT-PCR were used.Results HOXA l l mRNA was detected in both stromal and glandular cells of normal endometrium bv in situ hybridization. But the expression levels in the glandular cells had a dramatic decline or even disappearance at mid-secretory stage.Semi-quantitative RT-PCR analysis, however, demonstrated that the total expression levels of HOXAll mRNA were markedly increased in the mid-secretory endometrium, which suggested that there was an increased expression in stromal cells. Similar results were obtained for PR gene expression in human endometrium by in situ hybridization and semi-quantitative RT-PCR analysis.Conclusion HOXAll gene spatial and temporal expression patterns were similar to that of PR gene in endometrium across menstrual cycle, and HOXA l l was closely related to the endometrial proltferation and differentiation during menstrual cycle, especially the establishment of receptive status in implantation.

  19. The Effects of Attitude Similarity, Spatial Relationship, and Task Difficulty on Interpersonal Attraction.

    Science.gov (United States)

    Krivonos, Paul D.

    1980-01-01

    Presents a study of the effects of the occupation of an individual's personal space on that individual's judgment of the invader when the invader's attitudes are known to the invadee. Also studies the effect of the difficulty of the task on the relationship between spatial orientation and interpersonal attraction. (JMF)

  20. In situ groundwater bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. Suitable Region for Flue-cured Tobacco (Nicotiana glauca L.) Planting Based on Spatial Scene Similarity%Suitable Region for Flue-cured Tobacco (Nicotiana glauca L.) Planting Based on Spatial Scene Similarity

    Institute of Scientific and Technical Information of China (English)

    Junxiang DONG; Danhuai GUO; Xiaodong SHAO

    2012-01-01

    [Objective] The aim was to establish a model based on spatial scene similarity, for which soil, slope, transport, water conservancy, light, social economic factors in suitable planting areas were all considered. A new suitable planting area of flue-cured tobacco was determined by comparison and analysis, with consideration of excellent area. [Method] Totaling thirty natural factors were chosen, which were clas- sified into nine categories, from Longpeng Town (LP) and Shaochong Town (SC) in Shiping County in Honghe Hani and Yi Autonomous Prefecture. [Result] According to weights, the factors from high to low were as follows: soil〉light〉elevation〉slope〉 water conservancy〉transport〉baking facility〉planting plans over the years〉others. The similarity of geographical conditions in the area was 0.894 3, which indicated that the planting conditions in the two regions are similar. If farmer population in unit area, farmland quantity for individual farmer, labors in every household, activity in planting flue-cured tobacco and work of local instructor were considered, the weights of different factors were as follows: farmer population in unit area〉farmland quantity for individual farmer〉farmers' activity in planting flue-cured tobacco〉educational back- ground〉labor force in every household〉instructor〉population of farmers' children at- tending school. The similarity of geographical conditions was 0.703 1, which indicated that it is none-natural factors that influence yield and quality of flue-cured tobacco. [Conclusion] According to analysis on suitable planting area of flue-cured tobacco based on assessment of spatial scene similarity, similarity of growing conditions in two spatial scenes can be analyzed and evaluated, which would promote further exploration on, influencing factors and effects on tobacco production.

  2. Spatial Similarity Assessment of Point Clusters%空间点群目标相似度计算

    Institute of Scientific and Technical Information of China (English)

    刘涛; 杜清运; 闫浩文

    2011-01-01

    顾及到视觉认知的Gestalt原则,提出了一种综合考虑到点群的空间关系、空间分布和几何特征,注重空间点群的整体描述的相似度计算模型。实验结果表明,相似度计算结果与直观认知比较一致。%With the consideration of Gestalt principles in visual cognition,this paper proposed a similarity assessment model which has a comprehensive consideration of point cluster's spatial relationships,spatial distribution and geometry attributes.The topology relationship of point cluster is defined using point cluster's topology neighbors,the direction relationship and distance relationship is defined using point cluster's standard deviation ellipse,and then the computation method of point cluster's topology,direction and distance similarity assessment is given out on this basis.Also the distribution range and the distribution density of point cluster and their similarity assessment method is put forward.Finally the formal five factors were combined to do a whole assessment of point clusters similarity.Experiment results show that the similarity assessment is consistent with intuitive cognition.

  3. Fungi in Bioremediation

    Science.gov (United States)

    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.

  4. Bioremediation of oil spills

    International Nuclear Information System (INIS)

    In-situ bioremediation of crude oil spills relies on either the indigenous microbes at the polluted site, whose degradative abilities are accelerated by adding such agents as fertilizers or dispersants, or on introducing pollutant-degrading microbes into the site (possibly accompanied by stimulatory chemicals). The bioremediation method to be used at a specific site must be selected to be suitable for that site and its environmental conditions. The basic components of bioremediation are outlined and the background information needed to understand the chemical and biological limitations of the technique are presented. Specifically, the microbial community, the crude oil substrate composition, and biological limiting factors are discussed. Generalized examples of bioremediation applications are illustrated. 10 refs

  5. Integrated Field, Laboratory, and Modeling Studies to Determine the Effects of Linked Microbial and Physical Spatial Heterogeneity on Engineered Vadose Zone Bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Fred Brokman; John Selker; Mark Rockhold

    2004-01-26

    While numerous techniques exist for remediation of contaminant plumes in groundwater or near the soil surface, remediation methods in the deep vadose zone are less established due to complex transport dynamics and sparse microbial populations. There is a lack of knowledge on how physical and hydrologic features of the vadose zone control microbial growth and colonization in response to nutrient delivery during bioremediation. Yet pollution in the vadose zone poses a serious threat to the groundwater resources lying deeper in the sediment. While the contaminants may be slowly degraded by native microbial communities, microbial degradation rates rarely keep pace with the spread of the pollutant. It is crucial to increase indigenous microbial degradation in the vadose zone to combat groundwater contamination.

  6. Integrated Field, Laboratory, and Modeling Studies to Determine the Effects of Linked Microbial and Physical Spatial Heterogeneity on Engineered Vadose Zone Bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Brockman, Fred J.; Selker, John S.; Rockhold, Mark L.

    2004-10-31

    Executive Summary - While numerous techniques exist for remediation of contaminant plumes in groundwater or near the soil surface, remediation methods in the deep vadose zone are less established due to complex transport dynamics and sparse microbial populations. There is a lack of knowledge on how physical and hydrologic features of the vadose zone control microbial growth and colonization in response to nutrient delivery during bioremediation. Yet pollution in the vadose zone poses a serious threat to the groundwater resources lying deeper in the sediment. While the contaminants may be slowly degraded by native microbial communities, microbial degradation rates rarely keep pace with the spread of the pollutant. It is crucial to increase indigenous microbial degradation in the vadose zone to combat groundwater contamination...

  7. Four-Dimensional Computerized Tomography (4D-CT) Reconstruction Based on the Similarity Measure of Spatial Adjacent Images

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shu-xu; ZHOU Ling-hong; CHEN Guang-jie; LIN Sheng-qu; YE Yu-sheng; ZHANG Hai-nan

    2008-01-01

    Objective:To investigate the feasibility of a 4D-CT reconstruction method based on the similarity principle of spatial adjacent images and mutual information measure. Methods:A motor driven sinusoidal motion platform made in house was used to create one-dimensional periodical motion that was along the longitudinal axis of the CT couch. The amplitude of sinusoidal motion was set to an amplitude of ±1 cm. The period of the motion was adjustable and set to 3.5 s. Phantom objects of two eggs were placed in a Styrofoam block, which in turn were placed on the motion platform. These objects were used to simulate volumes of interest undergoing ideal periodic motion. CT data of static phantom were acquired using a multi-slice general electric (GE) LightSpeed 16-slice CT scanner in an axial mode. And the CT data of periodical motion phantom were acquired in an axial and cine-mode scan. A software program was developed by using VC++ and VTK software tools to resort the CT data and reconstruct the 4D-CT. Then all of the CT data with same phase were sorted by the program into the same series based on the similarity principle of spatial adjacent images and mutual information measure among them, and 3D reconstruction of different phase CT data were completed by using the software. Results:All of the CT data were sorted accurately into different series based on the similarity principle of spatial adjacent images and mutual information measures among them. Compared with the unsorted CT data, the motion artifacts in the 3D reconstruction of sorted CT data were reduced significantly, and all of the sorted CT series result in a 4D-CT that reflected the characteristic of the periodical motion phantom. Conclusion:Time-resolved 4D-CT reconstruction can be implemented with any general multi-slice CT scanners based on the similarity principle of spatial adjacent images and mutual information measure.The process of the 4D-CT data acquisition and reconstruction were not restricted to the

  8. Quantifying Effects of Spatial Heterogeneity of Farmlands on Bird Species Richness by Means of Similarity Index Pairwise

    Directory of Open Access Journals (Sweden)

    Federico Morelli

    2013-01-01

    Full Text Available Many studies have shown how intensification of farming is the main cause of loss biodiversity in these environments. During the last decades, agroecosystems in Europe have changed drastically, mainly due to mechanization of agriculture. In this work, species richness in bird communities was examined on a gradient of spatial heterogeneity of farmlands, in order to quantify its effects. Four categories of farmland spatial heterogeneity were defined, based on landscape and landuse parameters. The impact of features increasing the spatial heterogeneity was quantified comparing the similarity indexes between bird communities in several farmlands of Central Italy. The effects of environmental variables on bird richness were analyzed using GLM. The results highlighted that landscape features surrogates of high nature values (HNVs of farmlands can increase more than 50% the bird species richness. The features more related to bird richness were hedgerows, scattered shrubs, uncultivated patches, and powerlines. The results confirm that the approach based on HNV for evaluating the farmlands is also suitable in order to study birds’ diversity. However, some species are more sensitive to heterogeneity, while other species occupy mainly homogeneous farmlands. As a consequence, different conservation methods must be considered for each farmland bird species.

  9. Bioremediation of nanomaterials

    Science.gov (United States)

    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.

  10. Bioremediation of Creosote - contaminated Soil

    OpenAIRE

    BYSS, Marius

    2008-01-01

    Bioremediation of creosote-contaminated soil was studied employing the methods of soil microbial biology and using new gas chromatography-mass spectrometry-mass spectrometry analytical approach. The changes of the soil microbial community under the polycyclic aromatic hydrocarbons (PAH) pollution impact were analyzed and described, as well as the changes during the bioremediation experiments. Laboratory-scale bioremediation experiments using the soil microbial community (consisted of bacteria...

  11. Bioremediation of oil spills

    International Nuclear Information System (INIS)

    The conversion of oil to environmentally benign chemicals such as water and carbon dioxide by 'hydrocarbon-eating' bacteria is described. The emphasis is on a new process to selectively increase the population of 'oil eating' bacteria, a development that became the foundation for the second-generation bioremediation accelerator, Inipol EAP-22. Second-generation bioremediation products focus on providing nitrogen and phosphorus, chemicals that are not present in crude oil in readily available form, but are essential for the synthesis of proteins, nucleic acids, phospholipids and the energy metabolism of the bacteria. Providing these chemicals in the proper amounts encourages the preferential growth of oil-degrading microbes already present in the local biomass, thus overcoming the major limiting factor for biodegradation. These second-generation bioremediation products also have strong oleophilic properties engineered into them, to assure that the nutrients essential for the bacteria are in contact with the oil. The first major test for second-generation bioremediation accelerators came with the clean-up of the oil spill from the Exxon Valdez, a disaster that contaminated more than 120 kilometres of Alaskan beaches along the shores of Prince William Sound. The Inipol EAP-22 successfully held the nutrients in contact with the oil for the duration of the treatment period, despite constant exposure to the washing action of the surf and occasional heavy rainstorms. Today, the accelerator is routinely used in cleaning up all types of ordinary spills including diesel fuel spills along railway right-of-ways, truck yards and refinery sludge. Conditions under which the application of the accelerator is likely to be most successful are described

  12. Similar processes but different environmental filters for soil bacterial and fungal community composition turnover on a broad spatial scale.

    Directory of Open Access Journals (Sweden)

    Nicolas Chemidlin Prévost-Bouré

    Full Text Available Spatial scaling of microorganisms has been demonstrated over the last decade. However, the processes and environmental filters shaping soil microbial community structure on a broad spatial scale still need to be refined and ranked. Here, we compared bacterial and fungal community composition turnovers through a biogeographical approach on the same soil sampling design at a broad spatial scale (area range: 13300 to 31000 km2: i to examine their spatial structuring; ii to investigate the relative importance of environmental selection and spatial autocorrelation in determining their community composition turnover; and iii to identify and rank the relevant environmental filters and scales involved in their spatial variations. Molecular fingerprinting of soil bacterial and fungal communities was performed on 413 soils from four French regions of contrasting environmental heterogeneity (Landesspatial variables also explained 3% to 9% of total variance. These variables highlighted significant spatial autocorrelation of both communities unexplained by the environmental variables measured and could partly be explained by dispersal limitations. Although the identified filters and their hierarchy were dependent on the region and organism, selection was systematically based on a common group of environmental variables: pH, trophic resources, texture and land use. Spatial autocorrelation was also important at

  13. Stone formation in peach fruit exhibits spatial coordination of the lignin and flavonoid pathways and similarity to Arabidopsis dehiscence

    Directory of Open Access Journals (Sweden)

    Piagnani M Claudia

    2010-02-01

    Full Text Available Abstract Background Lignification of the fruit endocarp layer occurs in many angiosperms and plays a critical role in seed protection and dispersal. This process has been extensively studied with relationship to pod shatter or dehiscence in Arabidopsis. Dehiscence is controlled by a set of transcription factors that define the fruit tissue layers and whether or not they lignify. In contrast, relatively little is known about similar processes in other plants such as stone fruits which contain an extremely hard lignified endocarp or stone surrounding a single seed. Results Here we show that lignin deposition in peach initiates near the blossom end within the endocarp layer and proceeds in a distinct spatial-temporal pattern. Microarray studies using a developmental series from young fruits identified a sharp and transient induction of phenylpropanoid, lignin and flavonoid pathway genes concurrent with lignification and subsequent stone hardening. Quantitative polymerase chain reaction studies revealed that specific phenylpropanoid (phenylalanine ammonia-lyase and cinnamate 4-hydroxylase and lignin (caffeoyl-CoA O-methyltransferase, peroxidase and laccase pathway genes were induced in the endocarp layer over a 10 day time period, while two lignin genes (p-coumarate 3-hydroxylase and cinnamoyl CoA reductase were co-regulated with flavonoid pathway genes (chalcone synthase, dihydroflavanol 4-reductase, leucoanthocyanidin dioxygen-ase and flavanone-3-hydrosylase which were mesocarp and exocarp specific. Analysis of other fruit development expression studies revealed that flavonoid pathway induction is conserved in the related Rosaceae species apple while lignin pathway induction is not. The transcription factor expression of peach genes homologous to known endocarp determinant genes in Arabidopsis including SHATTERPROOF, SEEDSTCK and NAC SECONDARY WALL THICENING PROMOTING FACTOR 1 were found to be specifically expressed in the endocarp while the

  14. Bioremediation of marine oil pollution

    International Nuclear Information System (INIS)

    An assessment is presented of the scientific and technological developments in the area of bioremediation and biodegradation of marine oil pollution. A number of allied technologies are also considered. The basic technology in bioremediation involves adding fertilizers to an oil spill to enhance the natural process of oil biodegradation. Bioremediation can be applied to open systems such as beach or land spills, or in closed and controlled environments such as storage containers, specially constructed or modified bioreactors, and cargo tanks. The major advantage of using closed environments is the opportunity to control the physical and nutritional parameters to optimize the rate of biodegradation. An evaluation of the state of the art of bioremediation in Canada is also included. Recommendations are made to involve the Canadian Transportation Development Centre in short-term research projects on bioremediation. These projects would include the use of a barge as a mobile bioreactor for the treatment of off-loaded oily waste products, the use of in-situ bioremediation to carry out extensive cleaning, degassing, and sludge remediation on board an oil tanker, and the use of a barge as a mobile bioreactor and facility for the bioremediation of bilges. 51 refs., 4 figs., 14 tabs

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

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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...

  17. ORD RESEARCH PRIORITIES IN BIOREMEDIATION

    Science.gov (United States)

    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,...

  18. Mechanisms of mercury bioremediation.

    Science.gov (United States)

    Essa, A M M; Macaskie, L E; Brown, N L

    2002-08-01

    Mercury is one of the most toxic heavy metals, and has significant industrial and agricultural uses. These uses have led to severe localized mercury pollution. Mercury volatilization after its reduction to the metallic form by mercury-resistant bacteria has been reported as a mechanism for mercury bioremediation [Brunke, Deckwer, Frischmuth, Horn, Lunsdorf, Rhode, Rohricht, Timmis and Weppen (1993) FEMS Microbiol. Rev. 11, 145-152; von Canstein, Timmis, Deckwer and Wagner-Dobler (1999) Appl. Environ. Microbiol. 65, 5279-5284]. The reduction/volatilization system requires to be studied further, in order to eliminate the escape of the metallic mercury into the environment. Recently we have demonstrated three different mechanisms for mercury detoxification in one organism, Klebsiella pneumoniae M426, which may increase the capture efficiency of mercury.

  19. Spatial organization of the glucosinolate-myrosinase system in brassica specialist aphids is similar to that of the host plant.

    OpenAIRE

    Bridges, Matthew; Jones, Alexandra M. E.; Bones, Atle M.; Hodgson, Chris; Cole, Rosemary; Bartlet, Elspeth; Wallsgrove, Roger; Karapapa, Vassiliki K; Watts, Nigel; Rossiter, John T.

    2002-01-01

    Secondary metabolites are important in plant defence against pests and diseases. Similarly, insects can use plant secondary metabolites in defence and, in some cases, synthesize their own products. The paper describes how two specialist brassica feeders, Brevicoryne brassicae (cabbage aphid) and Lipaphis erysimi (turnip aphid) can sequester glucosinolates (thioglucosides) from their host plants, yet avoid the generation of toxic degradation products by compartmentalizing myrosinase (thiogluco...

  20. Bioremediation of oil spills

    International Nuclear Information System (INIS)

    For some years now UK and European oil spill response agencies, together with oil companies having an exploration or production interest in the European area, have been developing interest in the possible use of bioremediation techniques in combatting oil spills. The interest has accelerated in the aftermath of Exxon Valdez but there is significant scepticism over the actual value of the technique. The promise of increased rates of oil degradation, using bacteria or nutrients, does not yet appear to have been properly validated and there is concern over possible knock-on environmental effects. In consequence the response agencies are reluctant to bring the technique into their current combat armory. Some of the questions raised are: What efficacious techniques are available and how were they proven? On what type of oils can they be used? What is the scope for their use (at sea, type of coastline, temperature limitations, etc.)? What are the short and long term effects? Does bioremediation really work and offer a potential tool for oil spill clean-up? How do cleaning rates compare with natural recovery? There are many others. The view of the European Commission is that there should be a coordinated effort to answer these questions, but that effort should be properly targeted. I concur strongly with this view. The tasks are too large and varied for piecemeal attention. The European Commission wishes to initiate appropriate coordinated work, directed at the needs of European nations but which will subsequently inform the international response community through the International Maritime Organization and its Oil Pollution Preparedness and Response Cooperation initiative

  1. Cognitive processing load during listening is reduced more by decreasing voice similarity than by increasing spatial separation between target and masker speech

    OpenAIRE

    Adriana A. Zekveld; Mary eRudner; Kramer, Sophia E.; Johannes eLyzenga; Jerker eRönnberg

    2014-01-01

    We investigated changes in speech recognition and cognitive processing load due to the masking release attributable to decreasing similarity between target and masker speech. This was achieved by using masker voices with either the same (female) gender as the target speech or different gender (male) and/or by spatially separating the target and masker speech using HRTFs. We assessed the relation between the signal-to-noise ratio required for 50% sentence intelligibility, the pupil response an...

  2. Systems biology approach to bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    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. Cognitive processing load during listening is reduced more by decreasing voice similarity than by increasing spatial separation between target and masker speech

    Directory of Open Access Journals (Sweden)

    Adriana A. Zekveld

    2014-04-01

    Full Text Available We investigated changes in speech recognition and cognitive processing load due to the masking release attributable to decreasing similarity between target and masker speech. This was achieved by using masker voices with either the same (female gender as the target speech or different gender (male and/or by spatially separating the target and masker speech using HRTFs. We assessed the relation between the signal-to-noise ratio required for 50% sentence intelligibility, the pupil response and cognitive abilities. We hypothesized that the pupil response, a measure of cognitive processing load, would be larger for co-located maskers and for same-gender compared to different-gender maskers. We further expected that better cognitive abilities would be associated with better speech perception and larger pupil responses as the allocation of larger capacity may result in more intense mental processing.In line with previous studies, the performance benefit from different-gender compared to same-gender maskers was larger for co-located masker signals. The performance benefit of spatially-separated maskers was larger for same-gender maskers. The pupil response was larger for same-gender than for different-gender maskers, but was not reduced by spatial separation. We observed associations between better perception performance and better working memory, better information updating, and better executive abilities when applying no corrections for multiple comparisons. The pupil response was not associated with cognitive abilities. Thus, although both gender and location differences between target and masker facilitate speech perception, only gender differences lower cognitive processing load. Presenting a more dissimilar masker may facilitate target-masker separation at a later (cognitive processing stage than increasing the spatial separation between the target and masker. The pupil response provides information about speech perception that complements

  4. In situ vadose zone bioremediation.

    Science.gov (United States)

    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.

  5. Enhanced in situ aerobic bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Sharfe, K. [CleanEARTH Solutions Ltd., Concord, ON (Canada)

    2007-07-01

    An enhanced in situ aerobic bioremediation process was described. The process used microbe supporting emulsifications to enhance bioavailability as well as to attenuate microbe competition and boost microbial production. Microbes were added prior to application and rapidly initiated bioremediation once applied to impacted areas. The microbe supporting emulsifiers were metabolically active. The study showed that exposed surface areas increased as hydrocarbon masses were divided, which in turn increased the water/substrate interface where microbial action occurred. Nutrients were used to ensure that crowding and waste accumulation were attenuated in order to ensure that the speed of growth and reproduction progressed exponentially. Water-carrying bacteria, enzymes and nutrients were adsorbed to the soil's particle surface and then diffused between particles. The sequestered hydrocarbons were then emulsified and removed in order to be bioremediated. It was concluded that biological catalysts were used to increase microbial activity and to trigger anabolic responses in microbes. Details of a biocatalyst laboratory solution analysis were also included. tabs., figs.

  6. The temporal and spatial pattern of histone H3 phosphorylation at serine 28 and serine 10 is similar in plants but differs between mono- and polycentric chromosomes.

    Science.gov (United States)

    Gernand, D; Demidov, D; Houben, A

    2003-01-01

    Immunolabeling using site-specific antibodies against phosphorylated histone H3 at serine 10 or serine 28 revealed in plants an almost similar temporal and spatial pattern of both post-translational modification sites at mitosis and meiosis. During the first meiotic division the entire chromosomes are highly H3 phosphorylated. In the second meiotic division, like in mitosis, the chromosomes contain high phosphorylation levels in the pericentromeric region and very little H3 phosphorylation along the arms of monocentric species. In the polycentric plant Luzula luzuloides phosphorylation at both serine positions occurs along the whole chromosomes, whereas in monocentric species, only the pericentromeric regions showed strong signals from mitotic prophase to telophase. No phosphorylated serine 10 or serine 28 was detectable on single chromatids at anaphase II resulting from equational segregation of rye B chromosome univalents during the preceding anaphase I. In addition, we found a high level of serine 28 as well as of serine 10 phosphorylation along the entire mitotic monocentric chromosomes after treatment of mitotic cells using the phosphatase inhibitor cantharidin. These observations suggest that histone H3 phosphorylation at serine 10 and 28 is an evolutionarily conserved event and both sites are likely to be involved in the same process, such as sister chromatid cohesion. PMID:14610360

  7. Intrinsic bioremediation of landfills interim report

    Energy Technology Data Exchange (ETDEWEB)

    Brigmon, R.L. [Westinghouse Savannah River Company, Aiken, SC (United States); 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).

  8. Intrinsic bioremediation of landfills interim report

    International Nuclear Information System (INIS)

    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)

  9. Diverse Metabolic Capacities of Fungi for Bioremediation.

    Science.gov (United States)

    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.

  10. BIOREMEDIATION OF LOW GRADE ORES

    OpenAIRE

    Rashmi Mishra*

    2016-01-01

    The research work presented in this paper is on a Bioremediation for the recovery of zinc from mining waste i.e. Low grade ore of Hindustan Zinc Limited. They are waste product for the mines, as the recovery process is expensive compared to the recovery product moreover it causes lots of pollution   Bioleaching Studies were carried out at different pH using mixed culture grown from mine water. Recovery of zinc in control set (without culture) was 8% in 37 days and at the same pH ...

  11. Bioremediation at a petroleum refinery

    International Nuclear Information System (INIS)

    This paper presents a summary of three projects at the Mobil Refinery in Torrance, California where bioremediation technologies were successfully employed for the remediation of hydrocarbon contaminated soil. The three projects represent variations of implementation of bioremediation, both in-situ and ex-situ. Soil from all of the projects was considered non-hazardous designated waste under the California Code of Regulations, Title 23, section 2522. The projects were permitted and cleanup requirements were defined with the Los Angeles Regional Water Quality Control Board. In all of the projects, different methods were used for supplying water, oxygen, and nutrients to the hydrocarbon degrading bacteria to stimulate growth. The Stormwater Retention Basin Project utilized in-situ mechanical mixing of soils to supply solid nutrients and oxygen, and a self-propelled irrigation system to supply water. The Tank Farm Lake project used an in-situ active bioventing technology to introduce oxygen, moisture, and vapor phase nutrients. The Tank 1340X247 project was an ex-situ bioventing remediation project using a drip irrigation system to supply water and dissolved nutrients, and a vapor extraction system to provide oxygen

  12. Monitoring and interpreting bioremediation effectiveness

    International Nuclear Information System (INIS)

    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

  13. Treatment of a mud pit by bioremediation.

    Science.gov (United States)

    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

  14. Petroleum biodegradation and oil spill bioremediation

    International Nuclear Information System (INIS)

    Hydrocarbon-utilizing microorganisms are ubiquitously distributed in the marine environment following oil spills. These microorganisms naturally biodegrade numerous contaminating petroleum hydrocarbons, thereby cleansing the oceans of oil pullutants. Bioremediation, which is accomplished by adding exogenous microbial populations or stimulating indigenous ones, attempts to raise the rates of degradation found naturally to significantly higher rates. Seeding with oil degraders has not been demonstrated to be effective, but addition of nitrogenous fertilizers has been shown to increase rates of petroleum biodegradation. In the case of the Exxon Valdez spill, the largest and most thoroughly studied application of bioremediation, the application of fertilizer (slow release or oleophilic) increased rates of biodegradation 3-5 times. Because of the patchiness of oil, an internally conserved compound, hopane, was critical for demonstrating the efficacy of bioremediation. Multiple regression models showed that the effectiveness of bioremediation depended upon the amount of nitrogen delivered, the concentration of oil, and time. (author)

  15. Biosurfactant-enhanced soil bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Kosaric, N.; Lu, G.; Velikonja, J. [Univ. of Western Ontario, London, Ontario (Canada)

    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.

  16. Bioremediation of wastewater using microalgae

    Science.gov (United States)

    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. Solvent enhanced bioremediation of weathered oil contamination

    International Nuclear Information System (INIS)

    This paper describes a novel bioremediation process for the treatment of oil spills on land. The method was developed specifically to deal with long term oil contamination where the volatile fractions have evaporated leaving the more recalcitrant fractions. A model system of sand and Kuwaiti crude oil was used to test the system. A combined treatment which introduced an additional solvent component was found to enhance mobility and availability of oil, enhancing bioremediation. (author)

  18. Modal Similarity

    OpenAIRE

    Vigo , Dr. Ronaldo

    2009-01-01

    Just as Boolean rules define Boolean categories, the Boolean operators define higher-order Boolean categories referred to as modal categories. We examine the similarity order between these categories and the standard category of logical identity (i.e. the modal category defined by the biconditional or equivalence operator). Our goal is 4-fold: first, to introduce a similarity measure for determining this similarity order; second, to show that such a measure is a good predictor of the similari...

  19. Web Similarity

    OpenAIRE

    Cohen, Andrew; Vitányi, Paul

    2015-01-01

    Normalized web distance (NWD) is a similarity or normalized semantic distance based on the World Wide Web or any other large electronic database, for instance Wikipedia, and a search engine that returns reliable aggregate page counts. For sets of search terms the NWD gives a similarity on a scale from 0 (identical) to 1 (completely different). The NWD approximates the similarity according to all (upper semi)computable properties. We develop the theory and give applications. The derivation of ...

  20. A geometric construction of traveling waves in a bioremediation.

    NARCIS (Netherlands)

    Beck, M.; Doelman, A.; Kaper, T.J.

    2005-01-01

    Bioremediation is a promising technique for cleaning contaminated soil. We study an idealized bioremediation model involving a substrate (contaminant to be removed), electron acceptor (added nutrient), and microorganisms in a one-dimensional soil column. Using geometric singular perturbation theory,

  1. A geometric construction of traveling waves in a bioremediation model

    NARCIS (Netherlands)

    M.A. Beck; A. Doelman; T.J. Kaper

    2006-01-01

    Bioremediation is a promising technique for cleaning contaminated soil. We study an idealized bioremediation model involving a substrate (contaminant to be removed), electron acceptor (added nutrient), and microorganisms in a one-dimensional soil column. Using geometric singular perturbation theory,

  2. Diverse Metabolic Capacities of Fungi for Bioremediation.

    Science.gov (United States)

    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

  3. Bioremediation of oil-contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    Balba, T. [Conestoga-Rovers and Associates, Calgary, AB (Canada)

    2003-07-01

    One of the most prevalent contaminants in subsurface soil and groundwater are petroleum hydrocarbons. This paper presented bioremediation of petroleum hydrocarbons as one of the most promising treatment technologies. Petroleum hydrocarbons are categorized into four simple fractions: saturates, aromatics, resins, and asphaltenes. Bioremediation refers to the treatment process whereby contaminants are metabolized into less toxic or nontoxic compounds by naturally occurring organisms. The various strategies include: use of constitutive enzymes, enzyme induction, co-metabolism, transfer of plasmids coding for certain metabolic pathways, and production of biosurfactants to enhance bioavailability of hydrophobic compounds. Three case studies were presented: (1) bioremediation of heavy oils in soil at a locomotive maintenance yard in California, involving a multi-step laboratory treatability study followed by a field demonstration achieving up to 94 per cent removal of TPH in less than 16 weeks, (2) bioremediation of light oils in soil at an oil refinery in Germany where a dual process was applied (excavation and in-situ treatment), achieving an 84 per cent reduction within 24 weeks, and (3) bioremediation of oil-contaminated desert soil in Kuwait which involved landfarming, composting piles, and bioventing soil piles, achieving an 80 per cent reduction within 12 months. 7 refs., 1 tab., 3 figs.

  4. Bioremediation of Petroleum Hydrocarbon Contaminated Sites

    Energy Technology Data Exchange (ETDEWEB)

    Fallgren, Paul

    2009-03-30

    Bioremediation has been widely applied in the restoration of petroleum hydrocarbon-contaminated. Parameters that may affect the rate and efficiency of biodegradation include temperature, moisture, salinity, nutrient availability, microbial species, and type and concentration of contaminants. Other factors can also affect the success of the bioremediation treatment of contaminants, such as climatic conditions, soil type, soil permeability, contaminant distribution and concentration, and drainage. Western Research Institute in conjunction with TechLink Environmental, Inc. and the U.S. Department of Energy conducted laboratory studies to evaluate major parameters that contribute to the bioremediation of petroleum-contaminated drill cuttings using land farming and to develop a biotreatment cell to expedite biodegradation of hydrocarbons. Physical characteristics such as soil texture, hydraulic conductivity, and water retention were determined for the petroleum hydrocarbon contaminated soil. Soil texture was determined to be loamy sand to sand, and high hydraulic conductivity and low water retention was observed. Temperature appeared to have the greatest influence on biodegradation rates where high temperatures (>50 C) favored biodegradation. High nitrogen content in the form of ammonium enhanced biodegradation as well did the presence of water near field water holding capacity. Urea was not a good source of nitrogen and has detrimental effects for bioremediation for this site soil. Artificial sea water had little effect on biodegradation rates, but biodegradation rates decreased after increasing the concentrations of salts. Biotreatment cell (biocell) tests demonstrated hydrocarbon biodegradation can be enhanced substantially when utilizing a leachate recirculation design where a 72% reduction of hydrocarbon concentration was observed with a 72-h period at a treatment temperature of 50 C. Overall, this study demonstrates the investigation of the effects of

  5. Soil mesocosm studies on atrazine bioremediation.

    Science.gov (United States)

    Sagarkar, Sneha; Nousiainen, Aura; Shaligram, Shraddha; Björklöf, Katarina; Lindström, Kristina; Jørgensen, Kirsten S; Kapley, Atya

    2014-06-15

    Accumulation of pesticides in the environment causes serious issues of contamination and toxicity. Bioremediation is an ecologically sound method to manage soil pollution, but the bottleneck here, is the successful scale-up of lab-scale experiments to field applications. This study demonstrates pilot-scale bioremediation in tropical soil using atrazine as model pollutant. Mimicking field conditions, three different bioremediation strategies for atrazine degradation were explored. 100 kg soil mesocosms were set-up, with or without atrazine application history. Natural attenuation and enhanced bioremediation were tested, where augmentation with an atrazine degrading consortium demonstrated best pollutant removal. 90% atrazine degradation was observed in six days in soil previously exposed to atrazine, while soil without history of atrazine use, needed 15 days to remove the same amount of amended atrazine. The bacterial consortium comprised of 3 novel bacterial strains with different genetic atrazine degrading potential. The progress of bioremediation was monitored by measuring the levels of atrazine and its intermediate, cyanuric acid. Genes from the atrazine degradation pathway, namely, atzA, atzB, atzD, trzN and trzD were quantified in all mesocosms for 60 days. The highest abundance of all target genes was observed on the 6th day of treatment. trzD was observed in the bioaugmented mesocosms only. The bacterial community profile in all mesocosms was monitored by LH-PCR over a period of two months. Results indicate that the communities changed rapidly after inoculation, but there was no drastic change in microbial community profile after 1 month. Results indicated that efficient bioremediation of atrazine using a microbial consortium could be successfully up-scaled to pilot scale.

  6. Technical Basis for Assessing Uranium Bioremediation Performance

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Technical Basis for Assessing Uranium Bioremediation Performance

    International Nuclear Information System (INIS)

    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

  8. Strategies for chromium bioremediation of tannery effluent.

    Science.gov (United States)

    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

  9. Natural and accelerated bioremediation research program plan

    International Nuclear Information System (INIS)

    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

  10. Optimization-based image reconstruction in x-ray computed tomography by sparsity exploitation of local continuity and nonlocal spatial self-similarity

    Science.gov (United States)

    Han-Ming, Zhang; Lin-Yuan, Wang; Lei, Li; Bin, Yan; Ai-Long, Cai; Guo-En, Hu

    2016-07-01

    The additional sparse prior of images has been the subject of much research in problems of sparse-view computed tomography (CT) reconstruction. A method employing the image gradient sparsity is often used to reduce the sampling rate and is shown to remove the unwanted artifacts while preserve sharp edges, but may cause blocky or patchy artifacts. To eliminate this drawback, we propose a novel sparsity exploitation-based model for CT image reconstruction. In the presented model, the sparse representation and sparsity exploitation of both gradient and nonlocal gradient are investigated. The new model is shown to offer the potential for better results by introducing a similarity prior information of the image structure. Then, an effective alternating direction minimization algorithm is developed to optimize the objective function with a robust convergence result. Qualitative and quantitative evaluations have been carried out both on the simulation and real data in terms of accuracy and resolution properties. The results indicate that the proposed method can be applied for achieving better image-quality potential with the theoretically expected detailed feature preservation. Project supported by the National Natural Science Foundation of China (Grant No. 61372172).

  11. In-situ bioremediation via horizontal wells

    International Nuclear Information System (INIS)

    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

  12. Bioremediation effectiveness following the Exxon Valdez spill

    International Nuclear Information System (INIS)

    Statistical analyses of changes in the composition of oil residues remaining on beaches following the Exxon Valdez oil spill in Prince William Sound have demonstrated that bioremediation was effective in accelerating oil removal. Extensive data were obtained in a joint bioremediation monitoring program conducted during the summer of 1990 by the US Environmental Protection Agency (EPA), the State of Alaska, and Exxon. Composition changes in the oil relative to hopane, a trace oil component very resistant to biodegradation, provided the basis for accurately determining rates and extent of biodegradation. Results show that on fertilized beaches the rate of oil biodegradation was from three to more than five times faster than on adjacent, unfertilized control beaches. Further, most hydrocarbon components of the oil were biodegraded simultaneously, although at different rates. On one beach studied, about 60 percent of the total hydrocarbons detectable by gas chromatograph and 45 percent of the total PAH were biodegraded in three months. Bioremediation effectiveness was determined to depend primarily on the amount of nitrogen fertilizer delivered to the sediment per unit of oil present, time, and the extent of oil degradation prior to fertilizer application. The results suggest ways to improve future bioremediation application strategies and monitoring

  13. Bioremediation: A countermeasure for marine oil spills

    International Nuclear Information System (INIS)

    Three main types of bioremediation techniques are currently being developed or used for treatment of oil spills: adding nutrients to oiled shorelines; adding microbes to oiled shorelines; and addition of nutrients and/or microbes to open water oil slicks. Since all these technologies attempt to accelerate biodegradation, the processes of biodegradation of oil are summarized. Some of the potential uses of this technology are discussed, including specific instances where bioremediation has been applied at oil spills. Guidelines for evaluating and monitoring bioremediation applications are presented. Of the three types of bioremediation discussed, nutrient addition seems to hold the most immediate promise, especially for use in areas that would be adversely affected by physical or other removal methods. Environments where nutrient addition may play an important role in shoreline treatment include sheltered shorelines that are heavily oiled, shorelines with subsurface oil, and sensitive environments, especially wetlands. Nutrient additions are less likely to be effective in environments that are already nutrient-rich and for short-term, immediate response actions. 41 refs., 1 tab

  14. Bioremediation: Effectiveness in reducing the ecological impact

    International Nuclear Information System (INIS)

    Bioremediation becomes an important technique in oil spill combat programmes. The purpose is to shorten the exposure time of biota to oil compounds, in order to reduce long term environmental effects. Although bioremediation products have the advantage of stimulating the natural capacity to degrade oil, there are some limitations to be considered. Application as a technique for first emergency actions following an oil spill is not effective, and can therefore be no alternative for dispersion or mechanical removal of floating or freshly stranded oil slicks. Acute toxic effects are related to the short term exposure to unweathered oils. An immediate removal of oil is necessary to reduce the extent of the environmental impact of an oil spill. Physical processes (transport, dilution and evaporation) are determining the initial fate of environmentally released oil. Biodegradation only becomes important as a process of removing oil in the next phase. It is the only effective way to further reduce the concentration of oil that is left in (intertidal) coastal areas. Bioremediation thus reduces the duration of the environmental impact of an oil spill. This is especially important in ecosystems with a low recovery potential (e.g., salt marshes, rocky shores). The experimental evaluation of bioremediation products is mainly based on the capacity to reduce fresh oil and the acute toxicity of the product itself, rather than on the capacity to enhance the further reduction of weathered oil and the toxicological consequences of higher release rates of intermediate metabolites produced during the biotransformation processes

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

    International Nuclear Information System (INIS)

    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

  16. Integrative analysis of the interactions between Geobacter spp. and sulfate-reducing bacteria during uranium bioremediation

    Directory of Open Access Journals (Sweden)

    D. R. Lovley

    2011-11-01

    Full Text Available Enhancing microbial U(VI reduction with the addition of organic electron donors is a promising strategy for immobilizing uranium in contaminated groundwaters, but has yet to be optimized because of a poor understanding of the factors controlling the growth of various microbial communities during bioremediation. In previous field trials in which acetate was added to the subsurface, there were two distinct phases: an initial phase in which acetate-oxidizing, U(VI-reducing Geobacter predominated and U(VI was effectively reduced and a second phase in which acetate-oxidizing sulfate reducing bacteria (SRB predominated and U(VI reduction was poor. The interaction of Geobacter and SRB was investigated both in sediment incubations that mimicked in situ bioremediation and with in silico metabolic modeling. In sediment incubations, Geobacter grew quickly but then declined in numbers as the microbially reducible Fe(III was depleted whereas the SRB grow more slowly and reached dominance after 30–40 days. Modeling predicted a similar outcome. Additional modeling in which the relative initial percentages of the Geobacter and SRB were varied indicated that there was little to no competitive interaction between Geobacter and SRB when acetate was abundant. Further simulations suggested that the addition of Fe(III would revive the Geobacter, but have little to no effect on the SRB. This result was confirmed experimentally. The results demonstrate that it is possible to predict the impact of amendments on important components of the subsurface microbial community during groundwater bioremediation. The finding that Fe(III availability, rather than competition with SRB, is the key factor limiting the activity of Geobacter during in situ uranium bioremediation will aid in the design of improved uranium bioremediation strategies.

  17. Integrative analysis of Geobacter spp. and sulfate-reducing bacteria during uranium bioremediation

    Directory of Open Access Journals (Sweden)

    D. Lovley

    2012-03-01

    Full Text Available Enhancing microbial U(VI reduction with the addition of organic electron donors is a promising strategy for immobilizing uranium in contaminated groundwaters, but has yet to be optimized because of a poor understanding of the factors controlling the growth of various microbial communities during bioremediation. In previous field trials in which acetate was added to the subsurface, there were two distinct phases: an initial phase in which acetate-oxidizing, U(VI-reducing Geobacter predominated and U(VI was effectively reduced and a second phase in which acetate-oxidizing sulfate reducing bacteria (SRB predominated and U(VI reduction was poor. The interaction of Geobacter and SRB was investigated both in sediment incubations that mimicked in situ bioremediation and with in silico metabolic modeling. In sediment incubations, Geobacter grew quickly but then declined in numbers as the microbially reducible Fe(III was depleted whereas the SRB grow more slowly and reached dominance after 30–40 days. Modeling predicted a similar outcome. Additional modeling in which the relative initial percentages of the Geobacter and SRB were varied indicated that there was little to no competitive interaction between Geobacter and SRB when acetate was abundant. Further simulations suggested that the addition of Fe(III would revive the Geobacter, but have little to no effect on the SRB. This result was confirmed experimentally. The results demonstrate that it is possible to predict the impact of amendments on important components of the subsurface microbial community during groundwater bioremediation. The finding that Fe(III availability, rather than competition with SRB, is the key factor limiting the activity of Geobacter during in situ uranium bioremediation will aid in the design of improved uranium bioremediation strategies.

  18. Integrative analysis of the interactions between Geobacter spp. and sulfate-reducing bacteria during uranium bioremediation

    Science.gov (United States)

    Barlett, M.; Zhuang, K.; Mahadevan, R.; Lovley, D. R.

    2011-11-01

    Enhancing microbial U(VI) reduction with the addition of organic electron donors is a promising strategy for immobilizing uranium in contaminated groundwaters, but has yet to be optimized because of a poor understanding of the factors controlling the growth of various microbial communities during bioremediation. In previous field trials in which acetate was added to the subsurface, there were two distinct phases: an initial phase in which acetate-oxidizing, U(VI)-reducing Geobacter predominated and U(VI) was effectively reduced and a second phase in which acetate-oxidizing sulfate reducing bacteria (SRB) predominated and U(VI) reduction was poor. The interaction of Geobacter and SRB was investigated both in sediment incubations that mimicked in situ bioremediation and with in silico metabolic modeling. In sediment incubations, Geobacter grew quickly but then declined in numbers as the microbially reducible Fe(III) was depleted whereas the SRB grow more slowly and reached dominance after 30-40 days. Modeling predicted a similar outcome. Additional modeling in which the relative initial percentages of the Geobacter and SRB were varied indicated that there was little to no competitive interaction between Geobacter and SRB when acetate was abundant. Further simulations suggested that the addition of Fe(III) would revive the Geobacter, but have little to no effect on the SRB. This result was confirmed experimentally. The results demonstrate that it is possible to predict the impact of amendments on important components of the subsurface microbial community during groundwater bioremediation. The finding that Fe(III) availability, rather than competition with SRB, is the key factor limiting the activity of Geobacter during in situ uranium bioremediation will aid in the design of improved uranium bioremediation strategies.

  19. Integrative analysis of Geobacter spp. and sulfate-reducing bacteria during uranium bioremediation

    Science.gov (United States)

    Barlett, M.; Zhuang, K.; Mahadevan, R.; Lovley, D.

    2012-03-01

    Enhancing microbial U(VI) reduction with the addition of organic electron donors is a promising strategy for immobilizing uranium in contaminated groundwaters, but has yet to be optimized because of a poor understanding of the factors controlling the growth of various microbial communities during bioremediation. In previous field trials in which acetate was added to the subsurface, there were two distinct phases: an initial phase in which acetate-oxidizing, U(VI)-reducing Geobacter predominated and U(VI) was effectively reduced and a second phase in which acetate-oxidizing sulfate reducing bacteria (SRB) predominated and U(VI) reduction was poor. The interaction of Geobacter and SRB was investigated both in sediment incubations that mimicked in situ bioremediation and with in silico metabolic modeling. In sediment incubations, Geobacter grew quickly but then declined in numbers as the microbially reducible Fe(III) was depleted whereas the SRB grow more slowly and reached dominance after 30-40 days. Modeling predicted a similar outcome. Additional modeling in which the relative initial percentages of the Geobacter and SRB were varied indicated that there was little to no competitive interaction between Geobacter and SRB when acetate was abundant. Further simulations suggested that the addition of Fe(III) would revive the Geobacter, but have little to no effect on the SRB. This result was confirmed experimentally. The results demonstrate that it is possible to predict the impact of amendments on important components of the subsurface microbial community during groundwater bioremediation. The finding that Fe(III) availability, rather than competition with SRB, is the key factor limiting the activity of Geobacter during in situ uranium bioremediation will aid in the design of improved uranium bioremediation strategies.

  20. Selenite bioremediation potential of indigenous microorganisms from industrial activated sludge.

    Science.gov (United States)

    Garbisu, C; Alkorta, I; Carlson, D E; Leighton, T; Buchanan, B B

    1997-12-01

    Ten bacterial strains were isolated from the activated sludge waste treatment system (BIOX) at the Exxon refinery in Benicia, California. Half of these isolates could be grown in minimal medium. When tested for selenite detoxification capability, these five isolates (members of the genera Bacillus, Pseudomonas, Enterobacter and Aeromonas), were capable of detoxifying selenite with kinetics similar to those of a well characterized Bacillus subtilis strain (168 Trp+) studied previously. The selenite detoxification phenotype of the Exxon isolates was stable to repeated transfer on culture media which did not contain selenium. Microorganisms isolated from the Exxon BIOX reactor were capable of detoxifying selenite. Treatability studies using the whole BIOX microbial community were also carried out to evaluate substrates for their ability to support growth and selenite bioremediation. Under the appropriate conditions, indigenous microbial communities are capable of remediating selenite in situ.

  1. Improving Bioremediation of PAH Contaminated Soils by Thermal Pretreatment

    OpenAIRE

    Bonten, L.T.C.

    2001-01-01

    Numerous sites and large volumes of sediments in the Netherlands are contaminated with polycyclic aromatic hydrocarbons (PAH), which are of great concern because of their toxic and carcinogenic effects. Since PAH tend to sorb very strongly to the soil matrix, bioremediation is a slow process with often high residual concentrations after remediation. In this study it was tried to develop methods to improve bioremediation, this means to decrease residual concentrations after bioremediation. In ...

  2. Metagenomic applications in environmental monitoring and bioremediation.

    Science.gov (United States)

    Techtmann, Stephen M; Hazen, Terry C

    2016-10-01

    With the rapid advances in sequencing technology, the cost of sequencing has dramatically dropped and the scale of sequencing projects has increased accordingly. This has provided the opportunity for the routine use of sequencing techniques in the monitoring of environmental microbes. While metagenomic applications have been routinely applied to better understand the ecology and diversity of microbes, their use in environmental monitoring and bioremediation is increasingly common. In this review we seek to provide an overview of some of the metagenomic techniques used in environmental systems biology, addressing their application and limitation. We will also provide several recent examples of the application of metagenomics to bioremediation. We discuss examples where microbial communities have been used to predict the presence and extent of contamination, examples of how metagenomics can be used to characterize the process of natural attenuation by unculturable microbes, as well as examples detailing the use of metagenomics to understand the impact of biostimulation on microbial communities. PMID:27558781

  3. Biosurfactant-enhanced bioremediation of hydrophobic pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Cameotra, S.S.; Makkar, R.S. [Inst. of Microbial Technology, Chandigarh (India)

    2010-01-15

    Biosurfactants are surface-active compounds synthesized by a wide variety of microorganisms. They are molecules that have both hydrophobic and - philic domains and are capable of lowering the surface tension and the interfacial tension of the growth medium. Biosurfactants possess different chemical structures-lipopeptides, glycolipids, neutral lipids, and fatty acids. They are nontoxic biomolecules that are biodegradable. Biosurfactants also exhibit strong emulsification of hydrophobic compounds and form stable emulsions. Polycyclic aromatic hydrocarbons (PAHs), crude on sludge, and pesticides call be toxic, mutagenic, and carcinogenic compounds that pollute the environment. They are released into the environment as a result of oil spillage and by-products of coal treatment processes. The low water solubility of these compounds limits their availability to microorganisms, which is a potential problem for bioremediation of contaminated sites. Microbially produced surfactants enhance the bioavailability of these hydrophobic compounds for bioremediation. Therefore, biosurfactant-enhanced solubility of pollutants has potential hioremediation applications.

  4. Molecular Tools for Monitoring and Validating Bioremediation

    Science.gov (United States)

    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.

  5. Natural and accelerated bioremediation research program plan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Fungal Bioremediation of Creosote-contaminated Soil

    OpenAIRE

    BYSS, Marius

    2008-01-01

    The influence of two ligninolytic fungi (Pleurotus ostreatus and Irpex lacteus) on bioremediation of creosote-contaminated soil was studied. The thesis describes the polycyclic aromatic hydrocarbon concentration decrease during the laboratory-scale experiments and reveals the changes in the present soil microbial community under the influence of either fungus. The thesis compares different impact on PAH concentrations and soil microbial community depending on the fungus applied.

  8. Use of molecular techniques in bioremediation.

    Science.gov (United States)

    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

  9. Bioremediation Kinetics of Pharmaceutical Industrial Effluent

    OpenAIRE

    Šabić, M.; Vuković Domanovac, M.; Findrik Blažević, Z.; Meštrović, E.

    2015-01-01

    In recent years, concerns about the occurrence and fate of pharmaceuticals that could be present in water and wastewater has gained increasing attention. With the public’s enhanced awareness of eco-safety, environmentally benign methods based on microorganisms have become more accepted methods of removing pollutants from aquatic systems. This study investigates bioremediation of pharmaceutical wastewater from pharmaceutical company Pliva Hrvatska d.o.o., using activated sludge and bioaugmente...

  10. Field evaluations of marine oil spill bioremediation.

    OpenAIRE

    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 environ...

  11. [Response of soil microbial community to the bioremediation of soil contaminated with PAHs].

    Science.gov (United States)

    Zhang, Jing; Lin, Xian-gui; Liu, Wei-wei; Yin, Rui

    2012-08-01

    The diversity of bacterial community in soil contaminated with polycyclic aromatic hydrocarbons (PAHs) was investigated during the plant-microbe remediation enhanced by biosurfactant rhamnolips (RH), using the polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) method. The results showed that Shannon-Weaver diversity index was only 3.17 before bioremediation, and increased to 3.24-3.45 after bioremediation, in particular, highest value was found in the treatment of alfalfa (AL) inoculated with arbuscular mycorrhizal fungi (AM) and PAHs-degrading bacteria (DB) among all the treatments. The clustering analysis showed that the similarities of soil bacterial community of AL, AL + RH, AL + AM and AL + AM + RH were above 90%. At the same time, the similarity of AL + DB was much closer to those of the four treatments mentioned above. Additionally, when the bacterial communities of AL + DB + RH, AL + DB + AM and AL + DB + AM + RH were grouped together, the similarities of these three treatments were also higher than 80%. By sequence alignment, it was found that the predominant and characteristic bands in DGGE patterns were closely related with PAHs-degrading bacteria, such as Bacillus, Pseudomonas, Acidobacteria, Sphingmonas, Rhodopseudomonas, Firmicutes, and Methylocytaceae. Application of rhamnolipids in plant-microbe bioremediation not only improved the bioavailability of PAHs, but also had a simultaneous influence on the diversity of soil bacterial community, resulting in the efficient promotion of PAHs removal from soils.

  12. A scrutiny of heterogeneity at the TCE Source Area BioREmediation (SABRE) test site

    Science.gov (United States)

    Rivett, M.; Wealthall, G. P.; Mcmillan, L. A.; Zeeb, P.

    2015-12-01

    A scrutiny of heterogeneity at the UK's Source Area BioREmediation (SABRE) test site is presented to better understand how spatial heterogeneity in subsurface properties and process occurrence may constrain performance of enhanced in-situ bioremediation (EISB). The industrial site contained a 25 to 45 year old trichloroethene (TCE) dense non-aqueous phase liquid (DNAPL) that was exceptionally well monitored via a network of multilevel samplers and high resolution core sampling. Moreover, monitoring was conducted within a 3-sided sheet-pile cell that allowed a controlled streamtube of flow to be drawn through the source zone by an extraction well. We primarily focus on the longitudinal transect of monitoring along the length of the cell that provides a 200 groundwater point sample slice along the streamtube of flow through the DNAPL source zone. TCE dechlorination is shown to be significant throughout the cell domain, but spatially heterogeneous in occurrence and progress of dechlorination to lesser chlorinated ethenes - it is this heterogeneity in dechlorination that we primarily scrutinise. We illustrate the diagnostic use of the relative occurrence of TCE parent and daughter compounds to confirm: dechlorination in close proximity to DNAPL and enhanced during the bioremediation; persistent layers of DNAPL into which gradients of dechlorination products are evident; fast flowpaths through the source zone where dechlorination is less evident; and, the importance of underpinning flow regime understanding on EISB performance. Still, even with such spatial detail, there remains uncertainty over the dataset interpretation. These includes poor closure of mass balance along the cell length for the multilevel sampler based monitoring and points to needs to still understand lateral flows (even in the constrained cell), even greater spatial resolution of point monitoring and potentially, not easily proven, ethene degradation loss.

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

    OpenAIRE

    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 respirin...

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

    OpenAIRE

    FaraiMaphosa; ShaktiHLieten; DonnaE.Fennell

    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 ...

  15. BIOREMEDIATION OF PETROLEUM HYDROCARBON CONTAMINANTS IN MARINE HABITATS

    Science.gov (United States)

    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...

  16. Bioremediation of hydrocarbon contaminated surface water, groundwater, and soils

    International Nuclear Information System (INIS)

    Bioremediation is currently receiving considerable attention as a remediation option for sites contaminated with hazardous organic compounds. There is an enormous amount of interest in bioremediation, and numerous journals now publish research articles concerning some aspect of the remediation approach. A review of the literature indicates that two basic forms of bioremediation are currently being practiced: the microbiological approach and the microbial ecology approach. Each form has its advocates and detractors, and the microbiological approach is generally advocated by most of the firms that practice bioremediation. In this paper, the merits and disadvantages of these forms are reviewed and a conceptual approach is presented for assessing which form may be most useful for a particular contaminant situation. I conclude that the microbial ecology form of bioremediation may be the most useful for the majority of contaminant situations, and I will present two case histories in support of this hypothesis

  17. Scaling methods of sediment bioremediation processes and applications

    Energy Technology Data Exchange (ETDEWEB)

    Adriaens, P.; Li, M.Y.; Michalak, A.M. [The University of Michigan, Department of Civil and Environmental Engineering, 1351 Beal Ave, 175 EWRE Bldg, Ann Arbor, MI 48109-2125 (United States)

    2006-06-15

    Bioremediation has been argued to be one of the most cost-effective remediation technologies available to reduce soil, sediment, or groundwater contamination, particularly because this approach may allow for the implementation of in-place strategies. Recent trends have advocated the application of innovative sediment stabilization strategies through placement of (reactive) capping material to allow long-term biodegradation of contaminants in these complex biogeochemical environments. The potential long-term risk reduction associated with this approach requires a demonstration of causal relationships between sediment or contaminant stability on the one hand, and microbial reactivity on the other. The spatial analysis needed to fully understand and quantify these correlations requires sensitive probabilistic techniques. Geostatistics has been used for the characterization of multi-scale spatial patterns for the last few decades, and the analysis of microbial attributes has shown significant spatial structures on microbial abundance and activity. However, there is a dearth of information on the applicability of geostatistics to quantitatively describe the interaction between the microorganisms and their environment. Using the Passaic River (NJ) dioxin data as a model dataset, multiple scaling models were applied to scale and interpolate sampled dioxin data and derive dechlorination signatures in sediments. Unlike conventional geostatistic tools that are based on the point-to-point spatial structures, the new multi-scale model (M-Scale) introduces a new framework for spatial analysis in which regional values at different scales are anchored by the correlations to each other. Spatial dioxin distributions and microbial dechlorination signatures were used as benchmarks for comparison of M-Scale to ordinary kriging. The results from cross-validation and jackknifing approaches applied to these datasets were analyzed and compared using Quantile-Quantile (Q-Q) plots and

  18. POTENTIAL FUNGI FOR BIOREMEDIATION OF INDUSTRIAL EFFLUENTS

    Directory of Open Access Journals (Sweden)

    Vara Saritha

    2010-02-01

    Full Text Available Two fungi (unidentified were isolated from soil and marine environ-ments. These isolates were used for bioremediation of pulp and paper mill effluent at the laboratory scale. The treatment resulted in the reduction of color, lignin, and COD of the effluent in the order of 78.6%, 79.0%, and 89.4% in 21 days. A major part of reductions in these parameters occurred within 5 days of the treatment, which was also characterized by a steep decline in the pH of the effluent. The enzyme activity of these fungi was also tested, and the clearance zone was obtained in the plate assay.

  19. POTENTIAL FUNGI FOR BIOREMEDIATION OF INDUSTRIAL EFFLUENTS

    OpenAIRE

    Vara Saritha; Avasn Maruthi; Mukkanti, K.

    2010-01-01

    Two fungi (unidentified) were isolated from soil and marine environ-ments. These isolates were used for bioremediation of pulp and paper mill effluent at the laboratory scale. The treatment resulted in the reduction of color, lignin, and COD of the effluent in the order of 78.6%, 79.0%, and 89.4% in 21 days. A major part of reductions in these parameters occurred within 5 days of the treatment, which was also characterized by a steep decline in the pH of the effluent. The enzyme activity of t...

  20. Bioremediation of uranium contaminated Fernald soils

    International Nuclear Information System (INIS)

    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

  1. Bioremediation:A review of applications and problems to be resolved

    Institute of Scientific and Technical Information of China (English)

    ZHOU Qixing; HUA Tao

    2004-01-01

    This review article describes the factors affecting bioremediation processes including: goals of bioremediation and the optimal ecological conditions required; inoculation of microorganisms; cometabolism; bioavailability and its improvement; biological evolution and its utilization;monitoring and control of bioremediation processes; identification of bioremediation effectiveness and ecological remediation and its key elements. The current progress in bioremediation techniques is summarized. The direction of future development, research and applications is also examined.

  2. Bioremediation of petroleum hydrocarbons in soil environments

    International Nuclear Information System (INIS)

    The bioremediation of petroleum hydrocarbons in soil environments was reviewed via a literature survey and discussions with workers in relevant disciplines. The impacts of hydrocarbons on soil are discussed along with a range of methods available to assist in their decomposition by soil microorganisms. The range of petroleum-based materials considered includes conventional and synthetic crude oils, refined oils, sludges, asphalts and bitumens, drilling mud residues, creosote tars, and some pesticides. The degradability of hydrocarbons largely depends upon their aqueous solubility and their adsorption on soil surfaces and, therefore, is related to their molecular structures. The ease of decomposition decreases with increasing complexity of structure, in the order aliphatics > aromatics > heterocyclics and asphaltenes (most recalcitrant). Most soils contain an adequate population of microorganisms and hence bioaugmentation may only be needed in special circumstances. Decomposition is fastest in soils where the hydrocarbon loading rate, aeration, nutrition, moisture, and pH are all optimized. At spill sites there is little control over the application rate, although containment measures can assist in either limiting contamination or distributing it more evenly. The enhancement of bioremediation is discussed in light of all these factors. Other techniques such as enhanced aeration, hydrocarbon decomposition by anaerobic processes, surfactants, and burning are also discussed. 211 refs., 11 figs., 10 tabs

  3. Influence of a precepitator on bioremedial processes

    Directory of Open Access Journals (Sweden)

    Nježić Zvonko B.

    2010-01-01

    Full Text Available Natural environment represents a dynamic bioreactor with numerous chemical, biochemical and microbiological processes through which harmful materials are destroyed, so that living organisms and human beings are not endanger. Controlled anthropogenic actions can assist the natural ecosystem to become an efficient bioremedial unit and to reduce the level of effluents produced in the biotechnological transformations during massive food production. In this study, a monitoring system for the chemical oxygen demand (COD and the heavy metal levels in water was established, followed by construction and building of a precipitator in order to prevent discharging of sludge. The results contribute to the hypothesis of existence of in situ bioremedial processes in the observed ecosystem. The significant influence of the precipitator on the decrease of pollution was demonstrated: a decrease of both the COD value and the heavy metal levels downstream from the precipitator for about 15%. Therefore it can be concluded that the precipitator significantly contributes to the ecosystem by the reduction of pollutant level.

  4. Bioremediation of Carbendazim by Streptomyces albogriseolus

    Directory of Open Access Journals (Sweden)

    Ridhima Arya

    2014-08-01

    Full Text Available Carbendazim (methyl-1H-benzimidazol-2-ylcarbamate, or MBC is a benzimidazole fungicide which is used to protect crops against the attack of fungi. MBC has a half-life of about 3-12 months and remain persistent in the environment which may lead to many harmful consequences. Besides chemical and photo-catalytic degradation of pesticides, microbial degradation has now been evolved as a much effective and safer way to eliminate these harmful compounds from the environment. However, in the literature very few reports are available where microbial community is involved in degrading MBC. Hence, the present study was planned to investigate the role of microbes isolated from the field soils for the bioremediation of MBC. Soil samples were collected from wheat fields of northern regions of India. Enrichment culture technique was employed to isolate the bacterium which was found to be growing at higher concentrations of MBC up to 500µg/ml. After biochemical and morphological analysis, the bacterium was identified as Streptomyces albogriseolus. Streptomyces albogriseolus was found to degrade MBC in a time-dependent manner from the initial concentration of 29 ppm to 285.67ppb and 62.73ppb in 24hrs and 48hrs respectively. LCMS-MS analysis was carried out to detect 2-aminobenzimidazole, a metabolite formed after degradation in 10 hrs of growth which eventually disappeared after 24hrs of growth. The strain Streptomyces albogriseolus holds a promising potential to be an efficient MBC bioremediation agent.

  5. The Kwajalein bioremediation demonstration: Final technical report

    International Nuclear Information System (INIS)

    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

  6. The Kwajalein bioremediation demonstration: Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Bioremediation Kinetics of Pharmaceutical Industrial Effluent

    Directory of Open Access Journals (Sweden)

    M. Šabić

    2015-05-01

    Full Text Available In recent years, concerns about the occurrence and fate of pharmaceuticals that could be present in water and wastewater has gained increasing attention. With the public’s enhanced awareness of eco-safety, environmentally benign methods based on microorganisms have become more accepted methods of removing pollutants from aquatic systems. This study investigates bioremediation of pharmaceutical wastewater from pharmaceutical company Pliva Hrvatska d.o.o., using activated sludge and bioaugmented activated sludge with isolated mixed bacterial culture. The experiments were conducted in a batch reactor in submerged conditions, at initial concentration of organic matter in pharmaceutical wastewater, expressed as COD, 5.01 g dm–3 and different initial concentrations of activated sludge, which ranged from 1.16 to 3.54 g dm–3. During the experiments, the COD, pH, concentrations of dissolved oxygen and biomass were monitored. Microscopic analyses were performed to monitor the quality of activated sludge. Before starting with the bioremediation in the batch reactor, toxicity of the pharmaceutical wastewater was determined by toxicity test using bacteria Vibrio fischeri. The obtained results showed that the effective concentration of the pharmaceutical wastewater was EC50 = 17 % and toxicity impact index was TII50 = 5.9, meaning that the untreated pharmaceutical industrial effluent must not be discharged into the environment before treatment. The results of the pharmaceutical wastewater bioremediation process in the batch reactor are presented in Table 1. The ratio γXv ⁄ γX maintained high values throughout all experiments and ranged from 0.90 and 0.95, suggesting that the concentrations of biomass remained unchanged during the experiments. The important kinetic parameters required for performance of the biological removal process, namely μmax, Ks, Ki, Y and kd were calculated from batch experiments (Table 2. Figs. 1 and 2 show the experimental

  8. Enrichment of specific protozoan populations during in situ bioremediation of uranium-contaminated groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, Dawn; Giloteaux, L.; Williams, Kenneth H.; Wrighton, Kelly C.; Wilkins, Michael J.; Thompson, Courtney A.; Roper, Thomas J.; Long, Philip E.; Lovley, Derek

    2013-07-28

    The importance of bacteria in the anaerobic bioremediation of groundwater polluted with organic and/or metal contaminants is well-recognized and in some instances so well understood that modeling of the in situ metabolic activity of the relevant subsurface microorganisms in response to changes in subsurface geochemistry is feasible. However, a potentially significant factor influencing bacterial growth and activity in the subsurface that has not been adequately addressed is protozoan predation of the microorganisms responsible for bioremediation. In field experiments at a uranium-contaminated aquifer located in Rifle, CO, acetate amendments initially promoted the growth of metal-reducing Geobacter species followed by the growth of sulfate-reducers, as previously observed. Analysis of 18S rRNA gene sequences revealed a broad diversity of sequences closely related to known bacteriovorous protozoa in the groundwater prior to the addition of acetate. The bloom of Geobacter species was accompanied by a specific enrichment of sequences most closely related to the amoeboid flagellate, Breviata anathema, which at their peak accounted for over 80% of the sequences recovered. The abundance of Geobacter species declined following the rapid emergence of B. anathema. The subsequent growth of sulfate-reducing Peptococcaceae was accompanied by another specific enrichment of protozoa, but with sequences most similar to diplomonadid flagellates from the family Hexamitidae, which accounted for up to 100% of the sequences recovered during this phase of the bioremediation. These results suggest a prey-predator response with specific protozoa responding to increased availability of preferred prey bacteria. Thus, quantifying the influence of protozoan predation on the growth, activity, and composition of the subsurface bacterial community is essential for predictive modeling of in situ uranium bioremediation strategies.

  9. Semifield testing of a bioremediation tool for atrazine-contaminated soils: evaluating the efficacy on soil and aquatic compartments.

    Science.gov (United States)

    Chelinho, Sónia; Moreira-Santos, Matilde; Silva, Cátia; Costa, Catarina; Viana, Paula; Viegas, Cristina A; Fialho, Arsénio M; Ribeiro, Rui; Sousa, José Paulo

    2012-07-01

    The present study evaluated the bioremediation efficacy of a cleanup tool for atrazine-contaminated soils (Pseudomonas sp. ADP plus citrate [P. ADP + CIT]) at a semifield scale, combining chemical and ecotoxicological information. Three experiments representing worst-case scenarios of atrazine contamination for soil, surface water (due to runoff), and groundwater (due to leaching) were performed in laboratory simulators (100 × 40 × 20 cm). For each experiment, three treatments were set up: bioremediated, nonbioremediated, and a control. In the first, the soil was sprayed with 10 times the recommended dose (RD) for corn of Atrazerba and with P. ADP + CIT at day 0 and a similar amount of P. ADP at day 2. The nonbioremediated treatment consisted of soil spraying with 10 times the RD of Atrazerba (day 0). After 7 d of treatment, samples of soil (and eluates), runoff, and leachate were collected for ecotoxicological tests with plants (Avena sativa and Brassica napus) and microalgae (Pseudokirchneriella subcapitata) species. In the nonbioremediated soils, atrazine was very toxic to both plants, with more pronounced effects on plant growth than on seed emergence. The bioremediation tool annulled atrazine toxicity to A. sativa (86 and 100% efficacy, respectively, for seed emergence and plant growth). For B. napus, results point to incomplete bioremediation. For the microalgae, eluate and runoff samples from the nonbioremediated soils were extremely toxic; a slight toxicity was registered for leachates. After only 7 d, the ecotoxicological risk for the aquatic compartments seemed to be diminished with the application of P. ADP + CIT. In aqueous samples obtained from the bioremediated soils, the microalgal growth was similar to the control for runoff samples and slightly lower than control (by 11%) for eluates.

  10. In situ bioremediation of chlorinated solvent with natural gas

    International Nuclear Information System (INIS)

    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

  11. Bioremediation of oil-contaminated soils: A recipe for success

    Energy Technology Data Exchange (ETDEWEB)

    Wittenbach, S.A.

    1995-12-31

    Bioremediation of land crude oil and lube oil spills is an effective and economical option. Other options include road spreading (where permitted), thermal desorption, and off-site disposal. The challenge for environment and operations managers is to select the best approach for each remediation site. Costs and liability for off-site disposal are ever increasing. Kerr-McGee`s extensive field research in eastern and western Texas provides the data to support bioremediation as a legitimate and valid option. Both practical and economical bioremediation as a legitimate and valid option. Both practical and economical, bioremediation also offers a lower risk of, for example, Superfund clean-up exposure than off-site disposal.

  12. Bioremediation of chlorinated ethenes in aquifer thermal energy storage

    NARCIS (Netherlands)

    Ni, Z.

    2015-01-01

      Subjects: bioremediation; biodegradation; environmental biotechnology, subsurface and groundwater contamination; biological processes; geochemistry; microbiology The combination of enhanced natural attenuation (ENA) of chlorinated volatile organic compounds (CVOCs) and aquife

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

    Science.gov (United States)

    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...

  14. Heavy Metal Polluted Soils: Effect on Plants and Bioremediation Methods

    Directory of Open Access Journals (Sweden)

    G. U. Chibuike

    2014-01-01

    Full Text Available Soils polluted with heavy metals have become common across the globe due to increase in geologic and anthropogenic activities. Plants growing on these soils show a reduction in growth, performance, and yield. Bioremediation is an effective method of treating heavy metal polluted soils. It is a widely accepted method that is mostly carried out in situ; hence it is suitable for the establishment/reestablishment of crops on treated soils. Microorganisms and plants employ different mechanisms for the bioremediation of polluted soils. Using plants for the treatment of polluted soils is a more common approach in the bioremediation of heavy metal polluted soils. Combining both microorganisms and plants is an approach to bioremediation that ensures a more efficient clean-up of heavy metal polluted soils. However, success of this approach largely depends on the species of organisms involved in the process.

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

    NARCIS (Netherlands)

    Maphosa, F.; Lieten, S.; Dinkla, I.; Stams, A.J.M.; Fennel, D.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 bioremedi

  16. Chemometric assessment of enhanced bioremediation of oil contaminated soils

    DEFF Research Database (Denmark)

    Soleimani, Mohsen; Farhoudi, Majid; Christensen, Jan H.

    2013-01-01

    Bioremediation is a promising technique for reclamation of oil polluted soils. In this study, six methods for enhancing bioremediation were tested on oil contaminated soils from three refinery areas in Iran (Isfahan, Arak, and Tehran). The methods included bacterial enrichment, planting, and addi......Bioremediation is a promising technique for reclamation of oil polluted soils. In this study, six methods for enhancing bioremediation were tested on oil contaminated soils from three refinery areas in Iran (Isfahan, Arak, and Tehran). The methods included bacterial enrichment, planting...... steranes were used for determining the level and type of hydrocarbon contamination. The same methods were used to study oil weathering of 2 to 6 ring polycyclic aromatic compounds (PACs). Results demonstrated that bacterial enrichment and addition of nutrients were most efficient with 50% to 62% removal...

  17. ENHANCING STAKEHOLDER ACCEPTANCE OF BIOREMEDIATION TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Focht, Will; Albright, Matt; Anex, Robert P., Jr., ed.

    2009-04-21

    This project inquired into the judgments and beliefs of people living near DOE reservations and facilities at Oak Ridge, Tennessee; Hanford, Washington; and Los Alamos, Tennessee about bioremediation of subsurface contamination. The purpose of the investigation was to identify strategies based on these judgments and beliefs for enhancing public support of bioremediation. Several methods were used to collect and analyze data including content analysis of transcripts of face-to-face personal interviews, factor analysis of subjective perspectives using Q methodology, and statistical analysis of results from a large-sample randomized telephone survey. Content analysis of interview transcripts identified themes about public perceptions and constructions of contamination risk, risk management, and risk managers. This analysis revealed that those who have no employment relationship at the sites and are not engaged in technical professions are most concerned about contamination risks. We also found that most interviewees are unfamiliar with subsurface contamination risks and how they can be reduced, believe they have little control over exposure, are frustrated with the lack of progress in remediation, are concerned about a lack of commitment of DOE to full remediation, and distrust site managers to act in the public interest. Concern is also expressed over frequent site management turnover, excessive secrecy, ineffective and biased communication, perceived attempts to talk the public into accepting risk, and apparent lack of concern about community welfare. In the telephone survey, we asked respondents who were aware of site contamination about their perceptions of risk from exposure to subsurface contamination. Response analysis revealed that most people believe that they are at significant risk from subsurface contamination but they acknowledge that more education is needed to calibrate risk perceptions against scientific risk assessments. Most rate their personal

  18. Bioremediation of PCBs. CRADA final report

    Energy Technology Data Exchange (ETDEWEB)

    Klasson, K.T. [Oak Ridge National Lab., TN (United States). Chemical Technology Div., TN (United States); Abramowicz, D.A. [General Electric Co. Corporate Research and Development, Niskayuna, NY (United States)

    1996-06-01

    The Cooperative Research and Development Agreement was signed between Oak Ridge National Laboratory (ORNL) and General Electric Company (GE) on August 12, 1991. The objective was a collaborative venture between researchers at GE and ORNL to develop bioremediation of polychlorinated biphenyls (PCBs). The work was conducted over three years, and this report summarizes ORNL`s effort. It was found that the total concentration of PCBs decreased by 70% for sequential anaerobic-aerobic treatment compared with a 67% decrease for aerobic treatment alone. The sequential treatment resulted in PCB products with fewer chlorines and shorter halflives in humans compared with either anaerobic or aerobic treatment alone. The study was expected to lead to a technology applicable to a field experiment that would be performed on a DOE contaminated site.

  19. Bioremediation of PCBs. CRADA final report

    International Nuclear Information System (INIS)

    The Cooperative Research and Development Agreement was signed between Oak Ridge National Laboratory (ORNL) and General Electric Company (GE) on August 12, 1991. The objective was a collaborative venture between researchers at GE and ORNL to develop bioremediation of polychlorinated biphenyls (PCBs). The work was conducted over three years, and this report summarizes ORNL's effort. It was found that the total concentration of PCBs decreased by 70% for sequential anaerobic-aerobic treatment compared with a 67% decrease for aerobic treatment alone. The sequential treatment resulted in PCB products with fewer chlorines and shorter halflives in humans compared with either anaerobic or aerobic treatment alone. The study was expected to lead to a technology applicable to a field experiment that would be performed on a DOE contaminated site

  20. Bacteria and bioremediation of marine oil spills

    International Nuclear Information System (INIS)

    Virtually all marine ecosystems harbor indigenous hydrocarbon-degrading bacteria. These hydrocarbon degraders comprise less than one percent of the bacterial community in unpolluted environments, but generally increase to one to ten percent following petroleum contamination. Various hydrocarbons are degraded by these microorganisms at different rates, so there is an evolution in the residual hydrocarbon mixture, and some hydrocarbons and asphaltic petroleum hydrocarbons remain undegraded. Fortunately, these persistent petroleum pollutants are, for the most part, insoluble or are bound to solids; hence they are not biologically available and therefore not toxic to marine organisms. Carbon dioxide, water, and cellular biomass produced by the microorganisms from the degradable hydrocarbons may be consumed by detrital feeders and comprise the end products of the natural biological degradation process. Bioremediation attempts to accelerate the natural hydrocarbon degradation rates by overcoming factors that limit bacterial hydrocarbon degrading activities

  1. The role of soil hydrologic heterogeneity for modeling large-scale bioremediation protocols.

    Science.gov (United States)

    Romano, N.; Palladino, M.; Speranza, G.; Di Fiore, P.; Sica, B.; Nasta, P.

    2014-12-01

    The major aim of the EU-Life+ project EcoRemed (Implementation of eco-compatible protocols for agricultural soil remediation in Litorale Domizio-Agro Aversano NIPS) is the implementation of operating protocols for agriculture-based bioremediation of contaminated croplands, which also involves plants extracting pollutants being then used as biomasses for renewable energy production. The study area is the National Interest Priority Site (NIPS) called Litorale Domitio-Agro Aversano, which is located in the Campania Region (Southern Italy) and has an extent of about 200,000 ectars. In this area, a high-level spotted soil contamination is mostly due to the legal or outlaw industrial and municipal wastes, with hazardous consequences also on the quality of the groundwater. An accurate determination of the soil hydraulic properties to characterize the landscape heterogeneity of the study area plays a key role within the general framework of this project, especially in view of the use of various modeling tools for water flow and solute transport simulations and to predict the effectiveness of the adopted bioremediation protocols. The present contribution is part of an ongoing study where we are investigating the following research questions: a) Which spatial aggregation schemes seem more suitable for upscaling from point to block support? b) Which effective soil hydrologic characteristic schemes simulate better the average behavior of larger scale phytoremediation processes? c) Allowing also for questions a) and b), how the spatial variability of soil hydraulic properties affect the variability of plant responses to hydro-meteorological forcing?

  2. Development of combinatorial bacteria for metal and radionuclide bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    A. C. Matin, Ph. D.

    2006-06-15

    The grant concerned chromate [Cr(VI)] bioremediation and it was our aim from the outset to construct individual bacterial strains capable of improved bioremediation of multiple pollutants and to identify the enzymes suited to this end. Bacteria with superior capacity to remediate multiple pollutants can be an asset for the cleanup of DOE sites as they contain mixed waste. I describe below the progress made during the period of the current grant, providing appropriate context.

  3. Development of combinatorial bacteria for metal and radionuclide bioremediation

    International Nuclear Information System (INIS)

    The grant concerned chromate [Cr(VI)] bioremediation and it was our aim from the outset to construct individual bacterial strains capable of improved bioremediation of multiple pollutants and to identify the enzymes suited to this end. Bacteria with superior capacity to remediate multiple pollutants can be an asset for the cleanup of DOE sites as they contain mixed waste. I describe below the progress made during the period of the current grant, providing appropriate context

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

    OpenAIRE

    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 ...

  5. Bioremediation of crude oil spills in marine and terrestrial environments

    International Nuclear Information System (INIS)

    Bioremediation can be a safe and effective tool for dealing with crude oil spills, as demonstrated during the cleanup following the Exxon Valdez spill in Alaska. Crude oil has also been spilled on land, and bioremediation is a promising option for land spills too. Nevertheless, there are still areas where understanding of the phenomenon is rather incomplete. Research groups around the world are addressing these problems, and this symposium provides an excellent overview of some of this work

  6. Effectiveness of bioremediation for the Exxon Valdez oil spill

    Science.gov (United States)

    Bragg, James R.; Prince, Roger C.; Harner, E. James; Atlas, Ronald M.

    1994-03-01

    The effectiveness of bioremediation for oil spills has been difficult to establish on dynamic, heterogeneous marine shorelines. A new interpretative technique used following the 1989 Exxon Valdez spill in Alaska shows that fertilizer applications significantly increased rates of oil biodegradation. Biodegradation rates depended mainly on the concentration of nitrogen within the shoreline, the oil loading, and the extent to which natural biodegradation had already taken place. The results suggest ways to improve the effectiveness of bioremediation measures in the future.

  7. Effectiveness of bioremediation for the Exxon Valdez oil spill

    International Nuclear Information System (INIS)

    The effectiveness of bioremediation for oil spills has been difficult to establish on dynamic, heterogeneous marine shorelines. A new interpretative technique used following the 1989 Exxon Valdez spill in Alaska shows that fertilizer applications significantly increased rates of oil biodegradation. Biodegradation rates depended mainly on the concentration of nitrogen within the shoreline, the oil loading, and the extent to which natural biodegradation had already taken place. The results suggest ways to improve the effectiveness of bioremediation measures in the future. (Author)

  8. Endophytic microorganisms--promising applications in bioremediation of greenhouse gases.

    Science.gov (United States)

    Stępniewska, Z; Kuźniar, A

    2013-11-01

    Bioremediation is a technique that uses microbial metabolism to remove pollutants. Various techniques and strategies of bioremediation (e.g., phytoremediation enhanced by endophytic microorganisms, rhizoremediation) can mainly be used to remove hazardous waste from the biosphere. During the last decade, this specific technique has emerged as a potential cleanup tool only for metal pollutants. This situation has changed recently as a possibility has appeared for bioremediation of other pollutants, for instance, volatile organic compounds, crude oils, and radionuclides. The mechanisms of bioremediation depend on the mobility, solubility, degradability, and bioavailability of contaminants. Biodegradation of pollutions is associated with microbial growth and metabolism, i.e., factors that have an impact on the process. Moreover, these factors have a great influence on degradation. As a result, recognition of natural microbial processes is indispensable for understanding the mechanisms of effective bioremediation. In this review, we have emphasized the occurrence of endophytic microorganisms and colonization of plants by endophytes. In addition, the role of enhanced bioremediation by endophytic bacteria and especially of phytoremediation is presented.

  9. Bioremediation Well Borehole Soil Sampling and Data Analysis Summary Report for the 100-N Area Bioremediation Project

    Energy Technology Data Exchange (ETDEWEB)

    D. A. Gamon

    2009-09-28

    The purpose of this report is to present data and findings acquired during the drilling and construction of seven bioremediation wells in the 100-N Area in conjunction with remediation of the UPR-100-N-17 petroleum waste site.

  10. Laboratory experiment on bioremediation of crude oil by microbial consortium

    Energy Technology Data Exchange (ETDEWEB)

    Bao, M.; Wang, L. [Ocean Univ. of China, Qingdao, Shandong (China); Cao, L.; Sun, P. [State Ocean Administration, Qingdao, Shandong (China). North China Sea Environmental Monitoring Center

    2009-07-01

    Bioremediation has been touted as a promising method to remove oil from seawater. Studies have shown that 4 bacteria N1, N2, N3 and N4, isolated from seawater and oil-polluted coastal sediments in Qingdao Port, have a strong ability to degrade crude oil. Laboratory-scale experiments were conducted based on the microbial remediation functions of the bacterium flora. This paper reported on a study in which shake flask experiments were used to investigate the degradation conditions of the 4 strains. The flask tests were followed by small model basin tests where 4 strains were applied to the simulated marine environment. In the model basin test, the biodegradation rate reached 86.22 per cent. In the simulation experiment, the crude oil was analyzed by gas chromatography before and after biodegradation. The study showed that shake flask experiments provided better biodegradation conditions for the bacteria, resulting in high degradation rates. The 3 stages of laboratory-scale studies produced very similar biodegradation trends, although the degradation rate decreased slightly. It was concluded that the predominant flora chosen for this study may be feasible in treating contaminated sea water. 19 refs., 1 tab., 6 figs.

  11. Impact of organic carbon and nutrients mobilized during chemical oxidation on subsequent bioremediation of a diesel-contaminated soil.

    Science.gov (United States)

    Sutton, Nora B; Grotenhuis, Tim; Rijnaarts, Huub H M

    2014-02-01

    Remediation with in situ chemical oxidation (ISCO) impacts soil organic matter (SOM) and the microbial community, with deleterious effects on the latter being a major hurdle to coupling ISCO with in situ bioremediation (ISB). We investigate treatment of a diesel-contaminated soil with Fenton's reagent and modified Fenton's reagent coupled with a subsequent bioremediation phase of 187d, both with and without nutrient amendment. Chemical oxidation mobilized SOM into the liquid phase, producing dissolved organic carbon (DOC) concentrations 8-16 times higher than the untreated field sample. Higher aqueous concentrations of nitrogen and phosphorous species were also observed following oxidation; NH4(+) increased 14-172 times. During the bioremediation phase, dissolved carbon and nutrient species were utilized for microbial growth-yielding DOC concentrations similar to field sample levels within 56d of incubation. In the absence of nutrient amendment, the highest microbial respiration rates were correlated with higher availability of nitrogen and phosphorus species mobilized by oxidation. Significant diesel degradation was only observed following nutrient amendment, implying that nutrients mobilized by chemical oxidation can increase microbial activity but are insufficient for bioremediation. While all bioremediation occurred in the first 28d of incubation in the biotic control microcosm with nutrient amendment, biodegradation continued throughout 187d of incubation following chemical oxidation, suggesting that chemical treatment also affects the desorption of organic contaminants from SOM. Overall, results indicate that biodegradation of DOC, as an alternative substrate to diesel, and biological utilization of mobilized nutrients have implications for the success of coupled ISCO and ISB treatments.

  12. Enhancing Stakeholder Acceptance Of Bioremediation Technologies

    International Nuclear Information System (INIS)

    This project inquired into the judgments and beliefs of people living near DOE reservations and facilities at Oak Ridge, Tennessee; Hanford, Washington; and Los Alamos, Tennessee about bioremediation of subsurface contamination. The purpose of the investigation was to identify strategies based on these judgments and beliefs for enhancing public support of bioremediation. Several methods were used to collect and analyze data including content analysis of transcripts of face-to-face personal interviews, factor analysis of subjective perspectives using Q methodology, and statistical analysis of results from a large-sample randomized telephone survey. Content analysis of interview transcripts identified themes about public perceptions and constructions of contamination risk, risk management, and risk managers. This analysis revealed that those who have no employment relationship at the sites and are not engaged in technical professions are most concerned about contamination risks. We also found that most interviewees are unfamiliar with subsurface contamination risks and how they can be reduced, believe they have little control over exposure, are frustrated with the lack of progress in remediation, are concerned about a lack of commitment of DOE to full remediation, and distrust site managers to act in the public interest. Concern is also expressed over frequent site management turnover, excessive secrecy, ineffective and biased communication, perceived attempts to talk the public into accepting risk, and apparent lack of concern about community welfare. In the telephone survey, we asked respondents who were aware of site contamination about their perceptions of risk from exposure to subsurface contamination. Response analysis revealed that most people believe that they are at significant risk from subsurface contamination but they acknowledge that more education is needed to calibrate risk perceptions against scientific risk assessments. Most rate their personal

  13. ENHANCING STAKEHOLDER ACCEPTANCE OF BIOREMEDIATION TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Focht, Will; Albright, Matt; Anex, Robert P., Jr., ed.

    2009-04-21

    This project inquired into the judgments and beliefs of people living near DOE reservations and facilities at Oak Ridge, Tennessee; Hanford, Washington; and Los Alamos, Tennessee about bioremediation of subsurface contamination. The purpose of the investigation was to identify strategies based on these judgments and beliefs for enhancing public support of bioremediation. Several methods were used to collect and analyze data including content analysis of transcripts of face-to-face personal interviews, factor analysis of subjective perspectives using Q methodology, and statistical analysis of results from a large-sample randomized telephone survey. Content analysis of interview transcripts identified themes about public perceptions and constructions of contamination risk, risk management, and risk managers. This analysis revealed that those who have no employment relationship at the sites and are not engaged in technical professions are most concerned about contamination risks. We also found that most interviewees are unfamiliar with subsurface contamination risks and how they can be reduced, believe they have little control over exposure, are frustrated with the lack of progress in remediation, are concerned about a lack of commitment of DOE to full remediation, and distrust site managers to act in the public interest. Concern is also expressed over frequent site management turnover, excessive secrecy, ineffective and biased communication, perceived attempts to talk the public into accepting risk, and apparent lack of concern about community welfare. In the telephone survey, we asked respondents who were aware of site contamination about their perceptions of risk from exposure to subsurface contamination. Response analysis revealed that most people believe that they are at significant risk from subsurface contamination but they acknowledge that more education is needed to calibrate risk perceptions against scientific risk assessments. Most rate their personal

  14. Rehabilitation of oil polluted soils by bioremediation

    Science.gov (United States)

    Dumitru, Mihail; Parvan, Lavinia; Cioroianu, Mihai; Carmen, Sirbu; Constantin, Carolina

    2015-04-01

    In Romania about 50,000 ha are polluted with oil and/or brine. The main sources of pollution are the different activities using petroleum products: extraction, transport, treatment, refining and distribution. Taking into acoount the large areas and the cost per unit area, bioremediation was tested as a method of rehabilitation. To stimulate the performance of the bioremediation process for a polluted soil (luvisol) by 3% oil, different methods were tested: -application of a bacterial inoculum consisting of species of the Pseudomonas and Arthrobacter genera;- application of two types of absorbent materials, 16 t/ha peat and 16, respectively, 32 kg/ha Zeba (starch-based polymer, superabsorbent); -mineral fertilization with N200P200K200 and 5 different liquid fertilizer based on potassium humates extracted from lignite in a NPK matrix with micronutrients and added monosaccharides (4 and 8%). After 45 days from the treatment (60 days from pollution) the following observations have been noticed: • the application of only bacterial inoculum had no significant effect on the degradation of petroleum hydrocarbons; • the use of 650 l/ha AH-SH fertilizer (potassium humate in a NPK matrix) led to a 47% decrease of TPH (total petroleum hydrocarbons); • the application of 16 t/ha peat, together with the bacterial inoculum and the AH-SG2 liquid fertilizer (containing humates of potassium in a NPK matrix with microelements and 8% monosaccharides, in which the nitrogen is amide form) led to a 50% decrease of the TPH content; • the application of 16 kg/ha Zeba absorbent together with bacterial inoculum and 650 l/ha AH-SG1 liquid fertilizer (containing humates of potassium in a NPK matrix with microelements and 4% monosaccharide in which the nitrogen is in amide form) led to a 57% decrease of the TPH content; • the application of 32 kg/ha Zeba absorbent, together with the AH-SG2 fertilizer, led to a 58% decrease of the TPH content.

  15. SPATIO-TEXTUAL SIMILARITY JOIN

    Directory of Open Access Journals (Sweden)

    Ch Shylaja and Supreethi K.P

    2015-07-01

    Full Text Available Data mining is the process of discovering interesting patterns and knowledge from large amounts of data. Spatial databases store large space related data, such as maps, preprocessed remote sensing or medical imaging data. Modern mobile phones and mobile devices are equipped with GPS devices; this is the reason for the Location based services to gain significant attention. These Location based services generate large amounts of spatio- textual data which contain both spatial location and textual description. The spatiotextual objects have different representations because of deviations in GPS or due to different user descriptions. This calls for the need of efficient methods to integrate spatio-textual data. Spatio-textual similarity join meets this need. Spatio-textual similarity join: Given two sets of spatio-textual data, it finds all the similar pairs. Filter and refine framework will be developed to device the algorithms. The prefix filter technique will be extended to generate spatial and textual signatures and inverted indexes will be built on top of these signatures. Candidate pairs will be found using these indexes. Finally the candidate pairs will be refined to get the result. MBR-prefix based signature will be used to prune dissimilar objects. Hybrid signature will be used to support spatial and textual pruning simultaneously.

  16. Response of Archaeal Communities in Beach Sediments to Spilled Oil and Bioremediation

    OpenAIRE

    Röling, Wilfred F. M.; Couto de Brito, Ivana R.; Swannell, Richard P. J.; Head, Ian M.

    2004-01-01

    While the contribution of Bacteria to bioremediation of oil-contaminated shorelines is well established, the response of Archaea to spilled oil and bioremediation treatments is unknown. The relationship between archaeal community structure and oil spill bioremediation was examined in laboratory microcosms and in a bioremediation field trial. 16S rRNA gene-based PCR and denaturing gradient gel analysis revealed that the archaeal community in oil-free laboratory microcosms was stable for 26 day...

  17. Fungal Laccases and Their Applications in Bioremediation

    Directory of Open Access Journals (Sweden)

    Buddolla Viswanath

    2014-01-01

    Full Text Available 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.

  18. Oil bioremediation using insoluble nitrogen source.

    Science.gov (United States)

    Rosenberg, E; Legman, R; Kushmaro, A; Adler, E; Abir, H; Ron, E Z

    1996-11-15

    Oil bioremediation is limited by the availability of nitrogen and phosphorous, which are needed by the bacteria and not present in sufficient amounts in hydrocarbons. The supply of these two essential elements as water-soluble salts presents several problems. These include the rapid dilution of the salts in the large volumes of polluted land or water and their utilization by other bacteria that do not degrade oil. In addition, increasing the concentration of mobile nitrogen creates further environmental problems. The use of hydrophobic sources of nitrogen and phosphorous that have a low water solubility can overcome these problems. We have studied one such compound. F-1, that is not used by most bacteria but serves as a good nitrogen and phosphorous source for those bacterial strains that are capable of utilizing it. We have shown that bacteria using F-1 do not cross-feed other bacterial strains. Moreover, when the concentration of the pollutant is sufficiently reduced, the multiplication of the bacteria slows down until they become a negligible fraction of the bacterial population. Chemical analysis indicated that following a 28-day treatment of Alaskan crude oil, most of the hydrocarbons, including polycyclic aromatics, are degraded to undetectable levels. The C34 and C35 components were also degraded, although their degradation was not completed within this time period. In treatment of a sandy beach that was accidentally polluted with crude heavy oil, about 90% degradation was obtained within about 4 months at an outside average temperature of 5 -10 degrees C. PMID:8988651

  19. Bioremediation a promising technology for nuclear waste treatment

    International Nuclear Information System (INIS)

    Microbes play a primordial role in completing various elemental cycles namely carbon, nitrogen, sulfur, which are necessary for sustainability of planet Earth. This natural capability of microbes is employed to transform manmade compounds to their elemental forms. Redeployment of microbes for specific tasks needs a re-engineering of microbial metabolism to accelerate transformation. The most widely used approach is genetic modification but this approach has resulted into grievous failures due to inability of genetically modified organism to survive in natural environment. Consequently, development of new approach towards bioremediation was conceptualized, where desired metabolic capability were achieved using consortia of microorganisms having complementary metabolism. Of late, the potential of biofilm communities for bioremediation processes has been realized since it has many advantages over whole cells, used as biocatalysts. Naturally immobilized microbial biofilms exclude the necessity of cell-immobilization as biofilm cells are already embedded in self-produced exopolymers. Moreover, biofilm-mediated bioremediation offers a proficient and safer alternative to planktonic cells-mediated bioremediation because cells in a biofilm are more robust to toxic materials present in the waste as they are embedded in the matrix that provides a physical barrier. This presentation will highlight the importance of planktonic and sessile bacteria in bioremediation of a few nuclear waste compounds. (author)

  20. The development and application of engineered proteins for bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Trewhella, J. [ed.

    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.

  1. Bioremediation treatment of hydrocarbon-contaminated Arctic soils: influencing parameters.

    Science.gov (United States)

    Naseri, Masoud; Barabadi, Abbas; Barabady, Javad

    2014-10-01

    The Arctic environment is very vulnerable and sensitive to hydrocarbon pollutants. Soil bioremediation is attracting interest as a promising and cost-effective clean-up and soil decontamination technology in the Arctic regions. However, remoteness, lack of appropriate infrastructure, the harsh climatic conditions in the Arctic and some physical and chemical properties of Arctic soils may reduce the performance and limit the application of this technology. Therefore, understanding the weaknesses and bottlenecks in the treatment plans, identifying their associated hazards, and providing precautionary measures are essential to improve the overall efficiency and performance of a bioremediation strategy. The aim of this paper is to review the bioremediation techniques and strategies using microorganisms for treatment of hydrocarbon-contaminated Arctic soils. It takes account of Arctic operational conditions and discusses the factors influencing the performance of a bioremediation treatment plan. Preliminary hazard analysis is used as a technique to identify and assess the hazards that threaten the reliability and maintainability of a bioremediation treatment technology. Some key parameters with regard to the feasibility of the suggested preventive/corrective measures are described as well.

  2. Oil bioremediation processes in Brazilian marine environments : laboratory simulations

    International Nuclear Information System (INIS)

    Bioremediation methods have been used in Brazil to remediate contaminated soils from refinery residues. In particular, bioremediation is a process that can reduce the amount of oil that reaches shorelines, by enhancing natural biodegradation. This presentation presents the results of a laboratory study in which seawater contaminated with light crude oil was bioremediated in a period of 28 days using NPK fertilizer. Whole oil gas chromatography and gas chromatography-mass spectrometry analyses of the hydrocarbon fractions were used to determine the extent of oil biodegradation. It was determined that natural degradation occurred in the first 4 days, and mostly through the evaporation of light end n-alkanes. Biodegradation of n-alkanes was found to be most effective after 7 days, and no changes were observed in the relative abundance of steranes and triterpanes. It appears that the addition of NPK nutrient reduces the biodegradation potential of polyaromatic compounds. Seawater samples were also measured to determine the efficiency of bioremediation. The use of NPK fertilizer resulted in higher toxicity after 14 days probably due to the creation of metabolites as polyaromatic compounds biodegrade. Non toxic levels were found to be reestablished after 28 days of bioremediation. 16 refs., 4 tabs., 6 figs

  3. Bioremediation and detoxification of hydrocarbon pollutants in soil

    International Nuclear Information System (INIS)

    As a cleanup alterative, the bioremediation potential of soil, contaminated by spills of three medium petroleum distillates, jet fuel heating oil (No. 2 fuel oil) and diesel fuel was evaluated in controlled-temperature laboratory soil columns and in outdoor lysimeters. Solvent extraction followed by gas chromatography (GC) was used routinely for analysis of fuel residues. Occasionally, class separation and GC-mass spectrometry (GC-MS) were also used in residue characterization. The decrease in toxic residues was evaluated by Microtox and Ames tests. Seed germination and plant growth bioassays were also performed. Persistence and toxicity of the fuels increased in the order of jet fuel < heating oil < diesel fuel. Bioremediation consisting of liming, fertilization and tilling decreased the half-lives of the pollutants in soil by a factor of 2-3. Biodegradation was faster at 27C than at 17 or 37C, but hydrocarbon concentration and soil quality had only modest influence on biodegradation rates and did not preclude successful bioremediation of these contaminated soils within one growing season. Microbial activity measurements by the fluorescein diacetate hydrolysis assay confirmed that microbial activity was the principal force in hydrocarbon elimination. Bioremediation was highly effective in eliminating also the polycyclic aromatic components of diesel fuel. The bioremediation and detoxification of fuel-contaminated soil was corroborated by Microtox, Ames and plant growth bioassays

  4. Predicting bioremediation of hydrocarbons: laboratory to field scale.

    Science.gov (United States)

    Diplock, E E; Mardlin, D P; Killham, K S; Paton, G I

    2009-06-01

    There are strong drivers to increasingly adopt bioremediation as an effective technique for risk reduction of hydrocarbon impacted soils. Researchers often rely solely on chemical data to assess bioremediation efficiently, without making use of the numerous biological techniques for assessing microbial performance. Where used, laboratory experiments must be effectively extrapolated to the field scale. The aim of this research was to test laboratory derived data and move to the field scale. In this research, the remediation of over thirty hydrocarbon sites was studied in the laboratory using a range of analytical techniques. At elevated concentrations, the rate of degradation was best described by respiration and the total hydrocarbon concentration in soil. The number of bacterial degraders and heterotrophs as well as quantification of the bioavailable fraction allowed an estimation of how bioremediation would progress. The response of microbial biosensors proved a useful predictor of bioremediation in the absence of other microbial data. Field-scale trials on average took three times as long to reach the same endpoint as the laboratory trial. It is essential that practitioners justify the nature and frequency of sampling when managing remediation projects and estimations can be made using laboratory derived data. The value of bioremediation will be realised when those that practice the technology can offer transparent lines of evidence to explain their decisions. PMID:19232804

  5. Application of Fingerprinting Molecular Methods in Bioremediation Studies

    Science.gov (United States)

    Karpouzas, Dimitrios G.; Singh, Brajesh K.

    Bioremediation has been identified as a beneficial and effective strategy for the removal of recalcitrant environmental contaminants. Bioaugmentation of polluted environments with exogenous degrading microorganisms constitutes a major strategy of bioremediation. However, the ecological role of these strains and their impact on the endogenous microbial community of the micro-ecosystems where they are released should be known. Fingerprinting PCR-based methods, like denaturating gradient gel electrophoresis (DGGE) and terminal restriction fragment length polymorphism (TRFLP), could be used in studies exploring the ecology of pollutant-degrading microorganisms and their effects on the structure of the soil microbial community. This chapter provides a brief outline of the technical details involved in the application of DGGE and TRFLP fingerprinting in soil microbial ecology, with particular reference to bioremediation studies.

  6. Bioremediation of soluble heavy metals with recombinant Caulobacter crescentus.

    Science.gov (United States)

    Xu, Zhaohui; Lei, Yu; Patel, Jigar

    2010-01-01

    To achieve one-step separation of heavy metal ions from contaminated water, we have developed a novel bioremediation technology based on self-immobilization of the Caulobacter crescentus recombinant strain JS4022/p723-6H, which overexpresses hexahistidine peptide on the surface of the bacterial cells and serves as a whole-cell adsorbent for dissolved heavy metals. Biofilms formed by JS4022/p723-6H are effective at retaining cadmium from bacterial growth media or environmental water samples. Here we provide additional experiment data discussing the application potential of this new technology. Supplementation of calcium to the growth media produced robust JS4022/p723-6H cells by alleviating their sensitivity to chelators. After growth in the presence of 0.3% CaCl(2)·2H(2)O, double the amount of JS4022/p723-6H cells survived the treatment with 2 mM EDTA. Free cells of JS4022/p723-6H effectively sequestered 51% of the total cadmium from a Lake Erie water sample at pH 5.4, compared to 37% retrieved by the control strain. Similar levels of adsorption were observed at pH 4.2 as well. Cells of JS4022/p723-6H were tolerant of acid treatment for 90 min at pH ≥1.1 or 120 min at pH ≥2.5, which provides an avenue for the convenient regeneration of the bacterial cells metal-binding capacity with acidic solutions. Designs of possible bioreactors and an operation system are also presented.

  7. Technical considerations regarding toxicity testing of commercial bioremediation agents

    International Nuclear Information System (INIS)

    The toxicological evaluation of commercial bioremediation agents (CBAs) for use on oil spills is under consideration by the USEPA. Currently, acute and chronic bioassays are conducted with the CBA alone and with CBA that has been diluted with the water soluble fraction (WSF) of a crude oil. Endpoints are expressed as a concentration of the CBA. This approach may not address the toxicological issue of CBA use since it (1) does not determine if the CBA affects toxicity of the oil itself, and (2) does not consider temporal aspects associated with byproducts of oil degradation. The present study was conducted to address these issues. A CBA was mixed with unweathered crude oil from 1 to 42 days. The WSF of the mixture was then drawn off and acute bioassays were conducted with silverside minnows, Menidia beryllina, and mysid shrimp, Mysidopsis bahia. For silversides, 96-hr LC50 values ranged from 42.7% WSF after 1 day mixing to 10.5% after 42 days. Toxicity increased sharply between days 4 and 7 when the 96-hr LC50 dropped from 39.0 to 18.2% WSF. A similar trend occurred for mysid shrimp. The presence of the CBA caused a more rapid increase in the toxicity of the oil as compared to bioassays in which oil was mixed alone and then tested. These data indicate that the interaction of CBAs with oil, and associated temporal trends in toxicity, are important aspects to consider in hazard evaluation of these products. The current proposed CBA toxicity testing protocol does not effectively address these issues

  8. Microbial population changes during bioremediation of an experimental oil spill

    International Nuclear Information System (INIS)

    Three crude oil bioremediation techniques were applied in a randomized block field experiment simulating a coastal oil spill. Four treatments (no oil control, oil alone, oil plus nutrients, and oil plus nutrients plus an indigenous inoculum) were applied. In situ microbial community structures were monitored by phospholipid fatty acid (PLFA) analysis and 16S rDNA PCR-denaturing gradient gel electrophoresis (DGGE) to (i) identify the bacterial community members responsible for the decontamination of the site and (ii) define an end point for the removal of the hydrocarbon substrate. The results of PLFA analysis demonstrated a community shift in all plots from primarily eukaryotic biomass to gram-negative bacterial biomass with time. PLFA profiles from the oiled plots suggested increased gram-negative biomass and adaptation to metabolic stress compared to unoiled controls. DGGE analysis of untreated control plots revealed a simple, dynamic dominant population structure throughout the experiment. This banding pattern disappeared in all oiled plots, indicating that the structure and diversity of the dominant bacterial community changed substantially. No consistent differences were detected between nutrient-amended and indigenous inoculum-treated plots, but both differed from the oil-only plots. Prominent bands were excised for sequence analysis and indicated that oil treatment encouraged the growth of gram-negative microorganisms within the α-proteobacteria and Flexibacter-Cytophaga-Bacteroides phylum. α-Proteobacteria were never detected in unoiled controls. PLFA analysis indicated that by week 14 the microbial community structures of the oiled plots were becoming similar to those of the unoiled controls from the same time point, but DGGE analysis suggested that major differences in the bacterial communities remained

  9. Preliminary technology report for Southern Sector bioremediation

    International Nuclear Information System (INIS)

    This project was designed to demonstrate the potential of intrinsic bioremediation and phytoremediation in the Southern Sector of the A/M-Area at the Savannah River Site. A subsurface plume of trichloroethylene (TCE) and perchloroethylene (PCE) is present in the Lost Lake aquifer upgradient of the study site and is predicted to impact the area at some point in the future. The surface area along the Lost lake aquifer seep line where the plume is estimated to emerge was identified. Ten sites along the seep line were selected for biological, chemical, and contaminant treatability analyses. A survey was undertaken in this area to to quantify the microbial and plant population known to be capable of remediating TCE and PCE. The current groundwater quality upgradient and downgradient of the zone of influence was determined. No TCE or PCE was found in the soils or surface water from the area tested at this time. A TCE biodegradation treatability test was done on soil from the 10 selected locations. From an initial exposure of 25 ppm of TCE, eight of the samples biodegraded up to 99.9 percent of all the compound within 6 weeks. This biodegradation of TCE appears to be combination of aerobic and anaerobic microbial activity as intermediates that were detected in the treatability test include vinyl chloride (VC) and the dichloroethenes (DCE) 1,2-cis-dichloroethylene and 1,1-dichloroethylene. The TCE biological treatability studies were combines with microbiological and chemical analyses. The soils were found through immunological analysis with direct fluorescent antibodies (DFA) and microbiological analysis with direct fluorescent antibodies (DFA) and microbiological analysis to have a microbial population of methanotrophic bacteria that utilize the enzyme methane monooxygenase (MMO) and cometabolize TCE

  10. Metals, minerals and microbes: geomicrobiology and bioremediation.

    Science.gov (United States)

    Gadd, Geoffrey Michael

    2010-03-01

    Microbes play key geoactive roles in the biosphere, particularly in the areas of element biotransformations and biogeochemical cycling, metal and mineral transformations, decomposition, bioweathering, and soil and sediment formation. All kinds of microbes, including prokaryotes and eukaryotes and their symbiotic associations with each other and 'higher organisms', can contribute actively to geological phenomena, and central to many such geomicrobial processes are transformations of metals and minerals. Microbes have a variety of properties that can effect changes in metal speciation, toxicity and mobility, as well as mineral formation or mineral dissolution or deterioration. Such mechanisms are important components of natural biogeochemical cycles for metals as well as associated elements in biomass, soil, rocks and minerals, e.g. sulfur and phosphorus, and metalloids, actinides and metal radionuclides. Apart from being important in natural biosphere processes, metal and mineral transformations can have beneficial or detrimental consequences in a human context. Bioremediation is the application of biological systems to the clean-up of organic and inorganic pollution, with bacteria and fungi being the most important organisms for reclamation, immobilization or detoxification of metallic and radionuclide pollutants. Some biominerals or metallic elements deposited by microbes have catalytic and other properties in nanoparticle, crystalline or colloidal forms, and these are relevant to the development of novel biomaterials for technological and antimicrobial purposes. On the negative side, metal and mineral transformations by microbes may result in spoilage and destruction of natural and synthetic materials, rock and mineral-based building materials (e.g. concrete), acid mine drainage and associated metal pollution, biocorrosion of metals, alloys and related substances, and adverse effects on radionuclide speciation, mobility and containment, all with immense social

  11. TECHNOLOGIES FOR BIOREMEDIATION OF SOILS CONTAMINATED WITH PETROLEUM PRODUCTS

    Directory of Open Access Journals (Sweden)

    Roxana Gabriela POPA

    2012-05-01

    Full Text Available Biological methods for remediation of soils is based on the degradation of pollutants due to activity of microorganisms (bacteria, fungi. Effectiveness of biological decontamination of soils depends on the following factors: biodegradation of pollutants, type of microorganisms used, choice of oxidant and nutrient and subject to clean up environmental characteristics. Ex situ techniques for bioremediation of soils polluted are: composting (static / mechanical agitation, land farming and biopiles. Techniques in situ bioremediation of soils polluted are: bioventingul, biospargingul and biostimulation – bioaugumentarea.

  12. Developments in Bioremediation of Soils and Sediments Pollutedwith Metals and Radionuclides: 2. Field Research on Bioremediation of Metals and Radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Hazen, Terry C.; Tabak, Henry H.

    2007-03-15

    Bioremediation of metals and radionuclides has had manyfield tests, demonstrations, and full-scale implementations in recentyears. Field research in this area has occurred for many different metalsand radionuclides using a wide array of strategies. These strategies canbe generally characterized in six major categories: biotransformation,bioaccumulation/bisorption, biodegradation of chelators, volatilization,treatment trains, and natural attenuation. For all field applicationsthere are a number of critical biogeochemical issues that most beaddressed for the successful field application. Monitoring andcharacterization parameters that are enabling to bioremediation of metalsand radionuclides are presented here. For each of the strategies a casestudy is presented to demonstrate a field application that uses thisstrategy.

  13. Partial Characterization of Biosurfactant from Lactobacillus pentosus and Comparison with Sodium Dodecyl Sulphate for the Bioremediation of Hydrocarbon Contaminated Soil

    Directory of Open Access Journals (Sweden)

    A. B. Moldes

    2013-01-01

    Full Text Available The capability of a cell bound biosurfactant produced by Lactobacillus pentosus, to accelerate the bioremediation of a hydrocarbon-contaminated soil, was compared with a synthetic anionic surfactant (sodium dodecyl sulphate SDS-. The biosurfactant produced by the bacteria was analyzed by Fourier transform infrared spectroscopy (FTIR that clearly indicates the presence of OH and NH groups, C=O stretching of carbonyl groups and NH nebding (peptide linkage, as well as CH2–CH3 and C–O stretching, with similar FTIR spectra than other biosurfactants obtained from lactic acid bacteria. After the characterization of biosurfactant by FTIR, soil contaminated with 7,000 mg Kg−1 of octane was treated with biosurfactant from L. pentosus or SDS. Treatment of soil for 15 days with the biosurfactant produced by L. pentosus led to a 65.1% reduction in the hydrocarbon concentration, whereas SDS reduced the octane concentration to 37.2% compared with a 2.2% reduction in the soil contaminated with octane in absence of biosurfactant used as control. Besides, after 30 days of incubation soil with SDS or biosurfactant gave percentages of bioremediation around 90% in both cases. Thus, it can be concluded that biosurfactant produced by L. pentosus accelerates the bioremediation of octane-contaminated soil by improving the solubilisation of octane in the water phase of soil, achieving even better results than those reached with SDS after 15-day treatment.

  14. Performance Indicators for Uranium Bioremediation in the Subsurface: Basis and Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Long, Philip E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Yabusaki, Steven B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2006-12-29

    The purpose of this letter report is to identify performance indicators for in situ engineered bioremediation of subsurface uranium (U) contamination. This report focuses on in situ treatment of groundwater by biostimulation of extant in situ microbial populations (see http://128.3.7.51/NABIR/generalinfo/primers_guides/03_NABIR_primer.pdf for background information on bioremediation of metals and radionuclides). The treatment process involves amendment of the subsurface with an electron donor such as acetate, lactate, ethanol or other organic compound such that in situ microorganisms mediate the reduction of U(VI) to U(IV). U(VI) precipitates as uraninite or other insoluble U phase. Uranium is thus immobilized in place by such processes and is subject to reoxidation that may remobilize the reduced uranium. Related processes include augmenting the extant subsurface microbial populations, addition of electron acceptors, and introduction of chemically reducing materials such as zero-valent Fe. While metrics for such processes may be similar to those for in situ biostimulation, these related processes are not directly in the scope of this letter report.

  15. RNA-TGGE, a Tool for Assessing the Potential for Bioremediation in Impacted Marine Ecosystems

    Directory of Open Access Journals (Sweden)

    Krishna K. Kadali

    2015-08-01

    Full Text Available Cultivation-independent genomic approaches have greatly advanced our understanding of the ecology and diversity of microbial communities involved in biodegradation processes. However, much still needs to be resolved in terms of the structure, composition and dynamics of the microbial community in impacted ecosystems. Here we report on the RNA activity of the microbial community during the bioremediation process using RNA Temperature Gradient Gel Electrophoresis (RNA-TGGE. Dendrograms constructed from similarity matching data produced from the TGGE profiles separated a community exhibiting high remediation potential. Overall, increased Shannon Weaver Diversity indices (1–2.4 were observed in the high potential remediation treatment samples. The functionality of the microbial community was compared, with the microbial community showing the greatest organisation also showing the highest levels of hydrocarbon degradation. Subsequent sequencing of excised bands from the microbial community identified the presence of Gammaproteobacteria together with a number of uncultured bacteria. The data shows that RNA TGGE represents a simple, reproducible and effective tool for use in the assessment of a commercial bioremediation event, in terms of monitoring either the natural or augmented hydrocarbon-degrading microbial community.

  16. Pilot-scale bioremediation of a petroleum hydrocarbon-contaminated clayey soil from a sub-Arctic site

    Energy Technology Data Exchange (ETDEWEB)

    Akbari, Ali; Ghoshal, Subhasis, E-mail: subhasis.ghoshal@mcgill.ca

    2014-09-15

    Highlights: • Aeration and moisture addition alone caused extensive hydrocarbon biodegradation. • 30-day slurry reactor remediation endpoints attained in 385 days in biopiles. • High nitrogen concentrations inhibited hydrocarbon degradation. • Inhibition of biodegradation linked to lack of shifts in soil microbial community. - Abstract: Bioremediation is a potentially cost-effective solution for petroleum contamination in cold region sites. This study investigates the extent of biodegradation of petroleum hydrocarbons (C16–C34) in a pilot-scale biopile experiment conducted at 15 °C for periods up to 385 days, with a clayey soil, from a crude oil-impacted site in northern Canada. Although several studies on bioremediation of petroleum hydrocarbon-contaminated soils from cold region sites have been reported for coarse-textured, sandy soils, there are limited studies of bioremediation of petroleum contamination in fine-textured, clayey soils. Our results indicate that aeration and moisture addition was sufficient for achieving 47% biodegradation and an endpoint of 530 mg/kg for non-volatile (C16–C34) petroleum hydrocarbons. Nutrient amendment with 95 mg-N/kg showed no significant effect on biodegradation compared to a control system without nutrient but similar moisture content. In contrast, in a biopile amended with 1340 mg-N/kg, no statistically significant biodegradation of non-volatile fraction was detected. Terminal Restriction Fragment Length Polymorphism (T-RFLP) analyses of alkB and 16S rRNA genes revealed that inhibition of hydrocarbon biodegradation was associated with a lack of change in microbial community composition. Overall, our data suggests that biopiles are feasible for attaining the bioremediation endpoint in clayey soils. Despite the significantly lower biodegradation rate of 0.009 day{sup −1} in biopile tank compared to 0.11 day{sup −1} in slurry bioreactors for C16–C34 hydrocarbons, the biodegradation extents for this fraction

  17. Pilot-scale bioremediation of a petroleum hydrocarbon-contaminated clayey soil from a sub-Arctic site.

    Science.gov (United States)

    Akbari, Ali; Ghoshal, Subhasis

    2014-09-15

    Bioremediation is a potentially cost-effective solution for petroleum contamination in cold region sites. This study investigates the extent of biodegradation of petroleum hydrocarbons (C16-C34) in a pilot-scale biopile experiment conducted at 15°C for periods up to 385 days, with a clayey soil, from a crude oil-impacted site in northern Canada. Although several studies on bioremediation of petroleum hydrocarbon-contaminated soils from cold region sites have been reported for coarse-textured, sandy soils, there are limited studies of bioremediation of petroleum contamination in fine-textured, clayey soils. Our results indicate that aeration and moisture addition was sufficient for achieving 47% biodegradation and an endpoint of 530 mg/kg for non-volatile (C16-C34) petroleum hydrocarbons. Nutrient amendment with 95 mg-N/kg showed no significant effect on biodegradation compared to a control system without nutrient but similar moisture content. In contrast, in a biopile amended with 1340 mg-N/kg, no statistically significant biodegradation of non-volatile fraction was detected. Terminal Restriction Fragment Length Polymorphism (T-RFLP) analyses of alkB and 16S rRNA genes revealed that inhibition of hydrocarbon biodegradation was associated with a lack of change in microbial community composition. Overall, our data suggests that biopiles are feasible for attaining the bioremediation endpoint in clayey soils. Despite the significantly lower biodegradation rate of 0.009 day(-1) in biopile tank compared to 0.11 day(-1) in slurry bioreactors for C16-C34 hydrocarbons, the biodegradation extents for this fraction were comparable in these two systems.

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

    Directory of Open Access Journals (Sweden)

    Farai Maphosa

    2012-10-01

    Full Text Available 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.

  19. Bioremediation of a pesticide polluted soil: Case DDT

    International Nuclear Information System (INIS)

    1,1,1-trichloro-2,2 bis (p-chlorophenyl) ethane (DDT) has been used since the Second World War to control insect-borne diseases in humans and domestic animals. The use of these organochlorine insecticides has been banned in most countries because of its persistence in the environment, biomagnification and potential susceptibility to toxicity to higher animals. Bioremediation involves the use of microorganisms to degrade organic contaminants in the environment, transforming them into simpler and less dangerous, even harmless compounds. This decontamination strategy has low costs, and wide public acceptance, also it can take place on the site. Compared to other methods, bioremediation is a more promising and less expensive to eliminate contaminants in soil and water. In soil, compounds such as DDT, chlorinated biphenyls can be partially biodegraded by a group of aerobic bacteria that cometabolize the contaminant. The bioavailability of pollutants may be enhanced by treating the soil in the presence of contaminant mobilizing agents such as surfactants. In this review we discuss the different strategies for bioremediation of soil contaminated with DDT, including mechanisms and degradation pathways. The application of these techniques in contaminated soil is also described. This review also discusses which is the best strategy for bioremediation of DDT.

  20. U.S. bioremediation market: Yesterday, today, and tomorrow

    International Nuclear Information System (INIS)

    The use of bioremediation for full-scale cleanup has increased dramatically throughout the past 10 years. This growth in activity is expected to continue through the year 2000. It is estimated that fewer than 10 companies offered field-level bioremedial services prior to 1985. Although the market today still is dominated by a small number of companies, the total number of firms claiming to offer services and/or products for bioremediation purposes has grown to over 1,000. It is estimated that aggregate bioremediation revenues for 1994 through 2000 will equal $2 to $3 billion (1994 dollars). This revenue will be generated in the initial part of this 7-year period primarily from underground storage cleanup, with revenues from hazardous waste sites becoming an increasingly important factor by accounting for the majority of revenues in the latter years. Market opportunities exist in technology development and implementation including biosparging, centralized treatment facilities for petroleum-contaminated soils, biofilters, and improvements in the cost-effectiveness of the technology

  1. ENGINEERING ISSUE: IN SITU BIOREMEDIATION OF CONTAMINATED UNSATURATED SUBSURFACE SOILS

    Science.gov (United States)

    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 th...

  2. [Effects and Biological Response on Bioremediation of Petroleum Contaminated Soil].

    Science.gov (United States)

    Yang, Qian; Wu, Man-li; Nie, Mai-qian; Wang, Ting-ting; Zhang, Ming-hui

    2015-05-01

    Bioaugmentation and biostimulation were used to remediate petroleum-contaminated soil which were collected from Zichang city in North of Shaanxi. The optimal bioremediation method was obtained by determining the total petroleum hydrocarbon(TPH) using the infrared spectroscopy. During the bioremediation, number of degrading strains, TPH catabolic genes, and soil microbial community diversity were determined by Most Probable Number (MPN), polymerase chain reaction (PCR) combined agarose electrophoresis, and PCR-denaturing gradient electrophoresis (DGGE). The results in different treatments showed different biodegradation effects towards total petroleum hydrocarbon (TPH). Biostimulation by adding N and P to soils achieved the best degradation effects towards TPH, and the bioaugmentation was achieved by inoculating strain SZ-1 to soils. Further analysis indicated the positive correlation between catabolic genes and TPH removal efficiency. During the bioremediation, the number of TPH and alkanes degrading strains was higher than the number of aromatic degrading strains. The results of PCR-DGGE showed microbial inoculums could enhance microbial community functional diversity. These results contribute to understand the ecologically microbial effects during the bioremediation of petroleum-polluted soil.

  3. Bioremediation of chlorinated ethenes in aquifer thermal energy storage

    OpenAIRE

    Ni, Z

    2015-01-01

      Subjects: bioremediation; biodegradation; environmental biotechnology, subsurface and groundwater contamination; biological processes; geochemistry; microbiology The combination of enhanced natural attenuation (ENA) of chlorinated volatile organic compounds (CVOCs) and aquifer thermal energy storage (ATES) appears attractive because such integration provides a promising solution for redevelopment of urban areas in terms of improving the local environmental quality as well as achieving ...

  4. Legal and social concerns to the development of bioremediation technologies

    Energy Technology Data Exchange (ETDEWEB)

    Bilyard, G.R.; McCabe, G.H.; White, K.A.; Gajewski, S.W.; Hendrickson, P.L.; Jaksch, J.A.; Kirwan-Taylor, H.A.; McKinney, M.D.

    1996-09-01

    The social and legal framework within which bioremediation technologies must be researched, developed, and deployed in the US are discussed in this report. Discussions focus on policies, laws and regulations, intellectual property, technology transfer, and stakeholder concerns. These discussions are intended to help program managers, scientists and engineers understand the social and legal framework within which they work, and be cognizant of relevant issues that must be navigated during bioremediation technology research, development, and deployment activities. While this report focuses on the legal and social environment within which the DOE operates, the laws, regulations and social processes could apply to DoD and other sites nationwide. This report identifies specific issues related to bioremediation technologies, including those involving the use of plants; native, naturally occurring microbes; non-native, naturally occurring microbes; genetically engineered organisms; and microbial products (e.g., enzymes, surfactants, chelating compounds). It considers issues that fall within the following general categories: US biotechnology policy and the regulation of field releases of organisms; US environmental laws and waste cleanup regulations; intellectual property and patenting issues; technology transfer procedures for commercializing technology developed through government-funded research; stakeholder concerns about bioremediation proposals; and methods for assuring public involvement in technology development and deployment.

  5. Genomic and physiological perspectives on bioremediation processes at the FRC

    Energy Technology Data Exchange (ETDEWEB)

    Cardenas, Erick; Leigh, Mary Beth; Hemme, Christopher; Gentry, Terry; Harzman, Christina; Wu, Weimin; Criddle, Craig S.; Zhou, Jizhong; Marsh, Terence; Tiedje, James M.

    2006-04-05

    A suite of molecular and physiological studies, including metal reduction assays, metagenomics, functional gene microarrays and community sequence analyses were applied to investigate organisms involved in bioremediation processes at the ERSP Field Research Center and to understand the effects of stress on the makeup and evolution of microbial communities to inform effective remediation strategies.

  6. Legal and social concerns to the development of bioremediation technologies

    International Nuclear Information System (INIS)

    The social and legal framework within which bioremediation technologies must be researched, developed, and deployed in the US are discussed in this report. Discussions focus on policies, laws and regulations, intellectual property, technology transfer, and stakeholder concerns. These discussions are intended to help program managers, scientists and engineers understand the social and legal framework within which they work, and be cognizant of relevant issues that must be navigated during bioremediation technology research, development, and deployment activities. While this report focuses on the legal and social environment within which the DOE operates, the laws, regulations and social processes could apply to DoD and other sites nationwide. This report identifies specific issues related to bioremediation technologies, including those involving the use of plants; native, naturally occurring microbes; non-native, naturally occurring microbes; genetically engineered organisms; and microbial products (e.g., enzymes, surfactants, chelating compounds). It considers issues that fall within the following general categories: US biotechnology policy and the regulation of field releases of organisms; US environmental laws and waste cleanup regulations; intellectual property and patenting issues; technology transfer procedures for commercializing technology developed through government-funded research; stakeholder concerns about bioremediation proposals; and methods for assuring public involvement in technology development and deployment

  7. Electromigration of Contaminated Soil by Electro-Bioremediation Technique

    Science.gov (United States)

    Azhar, A. T. S.; Nabila, A. T. A.; Nurshuhaila, M. S.; Shaylinda, M. Z. N.; Azim, M. A. M.

    2016-07-01

    Soil contamination with heavy metals poses major environmental and human health problems. This problem needs an efficient method and affordable technological solution such as electro-bioremediation technique. The electro-bioremediation technique used in this study is the combination of bacteria and electrokinetic process. The aim of this study is to investigate the effectiveness of Pseudomonas putida bacteria as a biodegradation agent to remediate contaminated soil. 5 kg of kaolin soil was spiked with 5 g of zinc oxide. During this process, the anode reservoir was filled with Pseudomonas putida while the cathode was filled with distilled water for 5 days at 50 V of electrical gradient. The X-Ray Fluorescent (XRF) test indicated that there was a significant reduction of zinc concentration for the soil near the anode with 89% percentage removal. The bacteria count is high near the anode which is 1.3x107 cfu/gww whereas the bacteria count at the middle and near the cathode was 5.0x106 cfu/gww and 8.0x106 cfu/gww respectively. The migration of ions to the opposite charge of electrodes during the electrokinetic process resulted from the reduction of zinc. The results obtained proved that the electro-bioremediation reduced the level of contaminants in the soil sample. Thus, the electro-bioremediation technique has the potential to be used in the treatment of contaminated soil.

  8. Genetic engineering microbes for bioremediation/ biorecovery of uranium

    International Nuclear Information System (INIS)

    Bioremediation (both bioremoval and biorecovery) of metals is considered a feasible, economic and eco-friendly alternative to chemical methods of metal extraction, particularly when the metal concentration is very low. Scanty distribution along with poor ore quality makes biomining of uranium an attractive preposition. Biosorption, bioprecipitation or bioaccumulation of uranium, aided by recombinant DNA technology, offer a promising technology for recovery of uranium from acidic or alkaline nuclear waste, tailings or from sea-water. Genetic engineering of bacteria, with a gene encoding an acid phosphatase, has yielded strains that can bioprecipitate uranium from very low concentrations at acidic-neutral pH, in a relatively short time. Organisms overproducing alkaline phosphatase have been selected for uranium precipitation from alkaline waste. Such abilities have now been transferred to the radioresistant microbe Deinococcus radiodurans to facilitate in situ bioremediation of nuclear waste, with some success. Sulfate-reducing bacteria are being characterized for bioremediation of uranium in tailings with the dual objective of uranium precipitation and reduction of sulfate to sulphide. Certain marine cyanobacteria have shown promise for uranium biosorption to extracellular polysaccharides, and intracellular accumulation involving metal sequestering metallothionin proteins. Future work is aimed at understanding the genetic basis of these abilities and to engineer them into suitable organisms subsequently. As photosynthetic, nitrogen-fixing microbes, which are considerably resistant to ionizing radiations, cyanobacteria hold considerable potential for bioremediation of nuclear waste. (author)

  9. INTRINSIC BIOREMEDIATION OF A PETROLEUM-IMPACTED WETLAND

    Science.gov (United States)

    Following the 1994 San Jacinto River flood and oil spill in southeast Texas, a petroleum-contaminated wetland was reserved for a long-term research program to evaluate bioremediation as a viable spill response tool. The first phase of this program, presented in this paper, evalua...

  10. MICROBIAL POPULATION CHANGES DURING BIOREMEDIATION OF AN EXPERIMENTAL OIL SPILL

    Science.gov (United States)

    Three crude oil bioremediation techniques were applied in a randomized block field experiment simulating a coastal oil-spill. Four treatments (no oil control, oil alone, oil + nutrients, and oil + nutrients + an indigenous inoculum) were applied. In-situ microbial community str...

  11. BIOREMEDIATION AS A TECHNOLOGY: EXPERIENCES WITH THE EXXON VALDEZ SPILL

    Science.gov (United States)

    The results from our oil spill bioremediation project have demonstrated convincingly that fertilizers can be applied to oiled beaches to overcome nutrient limitations, thereby enhancing biodegradation of the oil. n Prince William Sound, the natural biodegradation rate of oil on t...

  12. Monitoring for bioremediation efficacy: The marrow marsh experience

    International Nuclear Information System (INIS)

    The US Environmental Protection Agency's Environmental Response Team analyzed samples taken from Marrow Marsh, Galveston Bay, Texas, to assess the efficacy of a bioremediation effort in the marsh following the Apex barges spill on July 28, 1990. Samples from the marsh had been collected over a 96-hour period following the first application of the bioremediation agent and then 25 days after the second application, which occurred 8 days after the first. Results of sample analyses to evaluate changes in the chemical characteristics of spilled oil failed to show evidence of oil degradation during the 96 hours after the initial treatment, but did show evidence of degradation 25 days after the second treatment-although differences between samples from treated and untreated sites were not evident. Because control areas had not been maintained after the second application, contamination by the bioremediation agent of previously untreated (control) areas may have occurred, perhaps negating the possibility of detecting differences between treated and control areas. Better preparedness to implement bioremediation and conduct monitoring might have increased the effectiveness of the monitoring effort

  13. OIL SPILL BIOREMEDIATION ON COASTAL SHORELINES: A CRITIQUE

    Science.gov (United States)

    The purpose of this chapter is not to provide an extensive review of the literature on oil spill bioremediation. For that, the reader is referred to Swannell et al. (1996), who have conducted the most exhaustive review I have yet to come across. Other reviews are also av...

  14. Use of Additives in Bioremediation of Contaminated Groundwater and Soil

    Science.gov (United States)

    This chapter reviews application of additives used in bioremediation of chlorinated solvents and fuels for groundwater and soil remediation. Soluble carbon substrates are applicable to most site conditions except aquifers with very high or very low groundwater flow. Slow-release ...

  15. Bioremediation of lead contaminated soil with Rhodobacter sphaeroides.

    Science.gov (United States)

    Li, Xiaomin; Peng, Weihua; Jia, Yingying; Lu, Lin; Fan, Wenhong

    2016-08-01

    Bioremediation with microorganisms is a promising technique for heavy metal contaminated soil. Rhodobacter sphaeroides was previously isolated from oil field injection water and used for bioremediation of lead (Pb) contaminated soil in the present study. Based on the investigation of the optimum culturing conditions and the tolerance to Pb, we employed the microorganism for the remediation of Pb contaminated soil simulated at different contamination levels. It was found that the optimum temperature, pH, and inoculum size for R. sphaeroides is 30-35 °C, 7, and 2 × 10(8) mL(-1), respectively. Rhodobacter sphaeroides did not remove the Pb from soil but did change its speciation. During the bioremediation process, more available fractions were transformed to less accessible and inert fractions; in particular, the exchangeable phase was dramatically decreased while the residual phase was substantially increased. A wheat seedling growing experiment showed that Pb phytoavailability was reduced in amended soils. Results inferred that the main mechanism by which R. sphaeroides treats Pb contaminated soil is the precipitation formation of inert compounds, including lead sulfate and lead sulfide. Although the Pb bioremediation efficiency on wheat was not very high (14.78% root and 24.01% in leaf), R. sphaeroides remains a promising alternative for Pb remediation in contaminated soil.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. In situ microcosms in aquifer bioremediation studies.

    Science.gov (United States)

    Mandelbaum, R T; Shati, M R; Ronen, D

    1997-07-01

    The extent to which aquifer microbiota can be studied under laboratory or simulated conditions is limited by our inability to authentically duplicate natural conditions in the laboratory. Therefore, extrapolation of laboratory results to real aquifer situations is often criticized, unless validation of the data is performed in situ. Reliable data acquisition is critical for the estimation of chemical and biological reaction rates of biodegradation processes in groundwater and as input data for mathematical models. Typically, in situ geobiochemical studies relied on the injection of groundwater spiked with compounds or bacteria of interest into the aquifer, followed by monitoring the changes over time and space. In situ microcosms provide a more confined study site for measurements of microbial reactions, yet closer to natural conditions than laboratory microcosms. Two basic types of in situ aquifer microcosm have been described in recent years, and both originated from in situ instruments initially designed for geochemical measurements. Gillham et al. [Ground Water 28 (1990) 858-862] constructed an instrument that isolates a portion of an aquifer for in situ biochemical rate measurements. More recently Shati et al. [Environ. Sci. Technol. 30 (1996) 2646-2653] modified a multilayer sampler for studying the activity of inoculated bacteria in a contaminated aquifer Keeping in mind recent advances in environmental microbiology methodologies such as immunofluorescence direct counts, oligonucleotide and PCR probes, fatty acid methyl esther analysis for the detection and characterization of bacterial communities, measurement of mRNA and expression of proteins, it is evident that much new information can now be gained from in situ work. Using in situ microcosms to study bioremediation efficiencies, the fate of introduced microorganisms and general geobiochemical aquifer processes can shed more realistic light on the microbial underworld. The aim of this paper is to

  18. Identifying Field-scale Bioremediation Status from Geochemical and Geophysical Data Using Dynamic Linear Models with Switching: Development and Application at a Uranium Contaminated Aquifer

    Science.gov (United States)

    Chen, J.; Hubbard, S. S.; Williams, K. H.

    2011-12-01

    Many field bioremediation experiments have been carried out at the uranium-contaminated Rifle Integrated Field Research Center (IFRC) site in Rifle, Colorado. The experiments include continuously injecting acetate and bromide for a period of 1~2 months and subsequently collecting multiple geochemical samples from downstream monitoring wells. Surface spectral induced polarization data along several two-dimensional (2D) profiles have also been collected to obtain information on the spatial distribution of biogeochemical transformations induced by bioremediation. The biogeochemical reactions vary over space and time during the contaminated aquifer transitions from iron to sulfate reduction following introduction of the electron donor. Developing methods to identify the onset and distribution of these transitions could improve our ability to assess remediation efficacy and sustainability. In this study, we develop a dynamic linear model with switching to identify bioremediation transitions using time-lapse aqueous geochemical data (such as Fe(II), sulfate, sulfide, acetate, uranium, chloride, and bromide concentrations) and spectral induced polarization data. We consider the multivariate geochemical concentrations as hidden random processes (observed at borehole locations but unknown at other locations) and the time-lapse geophysical data as observations at each location along the 2D profiles. The connection between the geophysical observations and geochemical time-series is determined by design matrices, which vary depending upon redox status. We describe the unknown biogeochemical events as categorical random variables. We take a Bayesian approach to estimate unknown parameters by first assigning suitable priors to the unknowns and then drawing many samples from their joint posterior distribution using Markov Chain Monte Carlo methods. The developed approach can provide us a wide range of information on bioremediation for evaluating the effectiveness of

  19. Shape Similarity Measures of Linear Entities

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The essential of feature matching technology lies in how to measure the similarity of spatial entities.Among all the possible similarity measures,the shape similarity measure is one of the most important measures because it is easy to collect the necessary parameters and it is also well matched with the human intuition.In this paper a new shape similarity measure of linear entities based on the differences of direction change along each line is presented and its effectiveness is illustrated.

  20. Monitoring bioremediation of atrazine in soil microcosms using molecular tools

    International Nuclear Information System (INIS)

    Molecular tools in microbial community analysis give access to information on catabolic potential and diversity of microbes. Applied in bioremediation, they could provide a new dimension to improve pollution control. This concept has been demonstrated in the study using atrazine as model pollutant. Bioremediation of the herbicide, atrazine, was analyzed in microcosm studies by bioaugmentation, biostimulation and natural attenuation. Genes from the atrazine degrading pathway atzA/B/C/D/E/F, trzN, and trzD were monitored during the course of treatment and results demonstrated variation in atzC, trzD and trzN genes with time. Change in copy number of trzN gene under different treatment processes was demonstrated by real-time PCR. The amplified trzN gene was cloned and sequence data showed homology to genes reported in Arthrobacter and Nocardioides. Results demonstrate that specific target genes can be monitored, quantified and correlated to degradation analysis which would help in predicting the outcome of any bioremediation strategy. - Highlights: ► Degradation of herbicide, atrazine. ► Comparison of bioremediation via bioaugmentation, biostimulation and natural attenuation. ► Gene profile analysis in all treatments. ► Variation in trzN gene numbers correlated to degradation efficiency. ► Cloning and sequence analysis of trzN gene demonstrates very high homology to reported gene. - This study demonstrates the use of molecular tools in bioremediation to monitor and track target genes; correlates the results with degradation and thereby predicts the efficiency of treatment.

  1. Bioremediation potential of diesel-contaminated Libyan soil.

    Science.gov (United States)

    Koshlaf, Eman; Shahsavari, Esmaeil; Aburto-Medina, Arturo; Taha, Mohamed; Haleyur, Nagalakshmi; Makadia, Tanvi H; Morrison, Paul D; Ball, Andrew S

    2016-11-01

    Bioremediation is a broadly applied environmentally friendly and economical treatment for the clean-up of sites contaminated by petroleum hydrocarbons. However, the application of this technology to contaminated soil in Libya has not been fully exploited. In this study, the efficacy of different bioremediation processes (necrophytoremediation using pea straw, bioaugmentation and a combination of both treatments) together with natural attenuation were assessed in diesel contaminated Libyan soils. The addition of pea straw was found to be the best bioremediation treatment for cleaning up diesel contaminated Libyan soil after 12 weeks. The greatest TPH degradation, 96.1% (18,239.6mgkg(-1)) and 95% (17,991.14mgkg(-1)) were obtained when the soil was amended with pea straw alone and in combination with a hydrocarbonoclastic consortium respectively. In contrast, natural attenuation resulted in a significantly lower TPH reduction of 76% (14,444.5mgkg(-1)). The presence of pea straw also led to a significant increased recovery of hydrocarbon degraders; 5.7log CFU g(-1) dry soil, compared to 4.4log CFUg(-1) dry soil for the untreated (natural attenuation) soil. DGGE and Illumina 16S metagenomic analyses confirm shifts in bacterial communities compared with original soil after 12 weeks incubation. In addition, metagenomic analysis showed that original soil contained hydrocarbon degraders (e.g. Pseudoxanthomonas spp. and Alcanivorax spp.). However, they require a biostimulant (in this case pea straw) to become active. This study is the first to report successful oil bioremediation with pea straw in Libya. It demonstrates the effectiveness of pea straw in enhancing bioremediation of the diesel-contaminated Libyan soil.

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

    Science.gov (United States)

    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...

  3. Approximate similarity search

    OpenAIRE

    Amato, Giuseppe

    2000-01-01

    Similarity searching is fundamental in various application areas. Recently it has attracted much attention in the database community because of the growing need to deal with large volume of data. Consequently, efficiency has become a matter of concern in design. Although much has been done to develop structures able to perform fast similarity search, results are still not satisfactory, and more research is needed. The performance of similarity search for complex features deteriorates and does...

  4. Similarity Structure of Wave-Collapse

    DEFF Research Database (Denmark)

    Rypdal, Kristoffer; Juul Rasmussen, Jens; Thomsen, Kenneth

    1985-01-01

    Similarity transformations of the cubic Schrödinger equation (CSE) are investigated. The transformations are used to remove the explicit time variation in the CSE and reduce it to differential equations in the spatial variables only. Two different methods for similarity reduction are employed and...

  5. Similarity transformations of MAPs

    Directory of Open Access Journals (Sweden)

    Andersen Allan T.

    1999-01-01

    Full Text Available We introduce the notion of similar Markovian Arrival Processes (MAPs and show that the event stationary point processes related to two similar MAPs are stochastically equivalent. This holds true for the time stationary point processes too. We show that several well known stochastical equivalences as e.g. that between the H 2 renewal process and the Interrupted Poisson Process (IPP can be expressed by the similarity transformations of MAPs. In the appendix the valid region of similarity transformations for two-state MAPs is characterized.

  6. Clustering by Pattern Similarity

    Institute of Scientific and Technical Information of China (English)

    Hai-xun Wang; Jian Pei

    2008-01-01

    The task of clustering is to identify classes of similar objects among a set of objects. The definition of similarity varies from one clustering model to another. However, in most of these models the concept of similarity is often based on such metrics as Manhattan distance, Euclidean distance or other Lp distances. In other words, similar objects must have close values in at least a set of dimensions. In this paper, we explore a more general type of similarity. Under the pCluster model we proposed, two objects are similar if they exhibit a coherent pattern on a subset of dimensions. The new similarity concept models a wide range of applications. For instance, in DNA microarray analysis, the expression levels of two genes may rise and fall synchronously in response to a set of environmental stimuli. Although the magnitude of their expression levels may not be close, the patterns they exhibit can be very much alike. Discovery of such clusters of genes is essential in revealing significant connections in gene regulatory networks. E-commerce applications, such as collaborative filtering, can also benefit from the new model, because it is able to capture not only the closeness of values of certain leading indicators but also the closeness of (purchasing, browsing, etc.) patterns exhibited by the customers. In addition to the novel similarity model, this paper also introduces an effective and efficient algorithm to detect such clusters, and we perform tests on several real and synthetic data sets to show its performance.

  7. New Similarity Functions

    DEFF Research Database (Denmark)

    Yazdani, Hossein; Ortiz-Arroyo, Daniel; Kwasnicka, Halina

    2016-01-01

    In data science, there are important parameters that affect the accuracy of the algorithms used. Some of these parameters are: the type of data objects, the membership assignments, and distance or similarity functions. This paper discusses similarity functions as fundamental elements in membership...

  8. Effect of alternating bioremediation and electrokinetics on the remediation of n-hexadecane-contaminated soil

    OpenAIRE

    Sa Wang; Shuhai Guo; Fengmei Li; Xuelian Yang; Fei Teng; Jianing Wang

    2016-01-01

    This study demonstrated the highly efficient degradation of n-hexadecane in soil, realized by alternating bioremediation and electrokinetic technologies. Using an alternating technology instead of simultaneous application prevented competition between the processes that would lower their efficiency. For the consumption of the soil dissolved organic matter (DOM) necessary for bioremediation by electrokinetics, bioremediation was performed first. Because of the utilization and loss of the DOM a...

  9. In situ bioremediation using horizontal wells. Innovative technology summary report

    International Nuclear Information System (INIS)

    In Situ Bioremediation (ISB) is the term used in this report for Gaseous Nutrient Injection for In Situ Bioremediation. This process (ISB) involves injection of air and nutrients (sparging and biostimulation) into the ground water and vacuum extraction to remove Volatile Organic Compounds (VOCs) from the vadose zone concomitant with biodegradation of the VOCs. This process is effective for remediation of soils and ground water contaminated with VOCs both above and below the water table. A full-scale demonstration of ISB was conducted as part of the Savannah River Integrated Demonstration: VOCs in Soils and Ground Water at Nonarid Sites. This demonstration was performed at the Savannah River Site from February 1992 to April 1993

  10. Contributions of biosurfactants to natural or induced bioremediation.

    Science.gov (United States)

    Lawniczak, Lukasz; Marecik, Roman; Chrzanowski, Lukasz

    2013-03-01

    The number of studies dedicated to evaluating the influence of biosurfactants on bioremediation efficiency is constantly growing. Although significant progress regarding the explanation of mechanisms behind biosurfactant-induced effects could be observed, there are still many factors which are not sufficiently elucidated. This corresponds to the fact that although positive influence of biosurfactants is often reported, there are also numerous cases where no or negative effect was observed. This review summarizes the recent finding in the field of biosurfactant-amended bioremediation, focusing mainly on a critical approach towards potential limitations and causes of failure while investigating the effects of biosurfactants on the efficiency of biodegradation and phytoextraction processes. It also provides a summary of successive steps, which should be taken into consideration when designing biosurfactant-related treatment processes. PMID:23400445

  11. Structural analysis of enzymes used for bioindustry and bioremediation.

    Science.gov (United States)

    Tanokura, Masaru; Miyakawa, Takuya; Guan, Lijun; Hou, Feng

    2015-01-01

    Microbial enzymes have been widely applied in the large-scale, bioindustrial manufacture of food products and pharmaceuticals due to their high substrate specificity and stereoselectivity, and their effectiveness under mild conditions with low environmental burden. At the same time, bioremedial techniques using microbial enzymes have been developed to solve the problem of industrial waste, particularly with respect to persistent chemicals and toxic substances. And finally, structural studies of these enzymes have revealed the mechanistic basis of enzymatic reactions, including the stereoselectivity and binding specificity of substrates and cofactors. The obtained structural insights are useful not only to deepen our understanding of enzymes with potential bioindustrial and/or bioremedial application, but also for the functional improvement of enzymes through rational protein engineering. This review shows the structural bases for various types of enzymatic reactions, including the substrate specificity accompanying cofactor-controlled and kinetic mechanisms.

  12. Kinetics of in situ bioremediation of Hanford groundwater

    International Nuclear Information System (INIS)

    Liquid wastes containing radioactive, hazardous, and regulated chemicals have been generated throughout the 40+ years of operations at the US Department of Energy's (DOE) Hanford Site. Some of these wastes were discharged to the soil column and many of the waste components, including nitrate, carbon tetrachloride (CCl4), and several radionuclides, have been detected in the Hanford groundwater. Current DOE policy prohibits the disposal of contaminated liquids directly to the environment, and may require the remediation of existing contaminated groundwaters. In situ bioremediation is one technology currently being developed at Hanford to meet the need for cost effective technologies to clean groundwater contaminated with CCl4, nitrate, and other organic and inorganic contaminants. This paper focuses on the latest results of an on-going effort to quantify the biological and chemical reactions that would occur during in situ bioremediation

  13. Microbial changes in rhizospheric soils contaminated with petroleum hydrocarbons after bioremediation

    Institute of Scientific and Technical Information of China (English)

    LIN Xin; LI Pei-jun; ZHOU Qi-xing; XU Hua-xia; ZHANG Hai-rong

    2004-01-01

    Effects of bioremediation on microbial communities in soils contaminated with petroleum hydrocarbons are a scientific problem to be solved. Changes in dominate microbial species and the total amount of microorganisms including bacteria and fungi in rhizospheric soils after bioremediation were thus evaluated using field bioremediation experiments. The results showed that there were changed dominant microorganisms including 11 bacterial strains which are mostly Gram positive bacteria and 6 fungal species which were identified. The total amount of microorganisms including bacteria and fungi increased after bioremediation of microbial agents combined with planting maize. On the contrary, fungi in rhizospheric soils were inhibited by adding microbial agents combined with planting soybean.

  14. Bioremediation Education Science and Technology (BEST) Program Annual Report 1999; TOPICAL

    International Nuclear Information System (INIS)

    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

  15. Bioremediation of severely weathered hydrocarbons: is it possible?

    International Nuclear Information System (INIS)

    Weathering processes of spilled hydrocarbons promote a reduced biodegradability of petroleum compounds mixtures, and consequently bioremediation techniques are often ruled out within the selection of suitable remediation approaches. This is truly relevant wherever old spills at abandoned industrial sites have to be remediated. However it is well known most of the remaining fractions and individual compounds of weathered oil are still biodegradable, although at slow rates than alkanes or no and two-ring aromatics. (Author)

  16. Petroleum-Degrading Enzymes: Bioremediation and New Prospects

    OpenAIRE

    R.S Peixoto; A.B. Vermelho; A.S. Rosado

    2011-01-01

    Anthropogenic forces, such as petroleum spills and the incomplete combustion of fossil fuels, have caused an accumulation of petroleum hydrocarbons in the environment. The accumulation of petroleum and its derivatives now constitutes an important environmental problem. Biocatalysis introduces new ways to improve the development of bioremediation strategies. The recent application of molecular tools to biocatalysis may improve bioprospecting research, enzyme yield recovery, and enzyme specific...

  17. Contributions of biosurfactants to natural or induced bioremediation

    OpenAIRE

    Ławniczak, Łukasz; Marecik, Roman; Chrzanowski, Łukasz

    2013-01-01

    The number of studies dedicated to evaluating the influence of biosurfactants on bioremediation efficiency is constantly growing. Although significant progress regarding the explanation of mechanisms behind biosurfactant-induced effects could be observed, there are still many factors which are not sufficiently elucidated. This corresponds to the fact that although positive influence of biosurfactants is often reported, there are also numerous cases where no or negative effect was observed. Th...

  18. Assisted bioremediation tests on three natural soils contaminated with benzene

    Directory of Open Access Journals (Sweden)

    Maria Manuela Carvalho

    2015-07-01

    Full Text Available Bioremediation is an attractive and useful method of remediation of soils contaminated with petroleum hydrocarbons because it is simple to maintain, applicable in large areas, is economic and enables an effective destruction of the contaminant. Usually, the autochthone microorganisms have no ability to degrade these compounds, and otherwise, the contaminated sites have inappropriate environmental conditions for microorganism’s development. These problems can be overcome by assisted bioremediation (bioaugmentation and/or biostimulation. In this study the assisted bioremediation capacity on the rehabilitation of three natural sub-soils (granite, limestone and schist contaminated with benzene was evaluated. Two different types of assisted bioremediation were used: without and with ventilation (bioventing. The bioaugmentation was held by inoculating the soil with a consortium of microorganisms collected from the protection area of crude oil storage tanks in a refinery. In unventilated trials, biostimulation was accomplished by the addition of a nutrient mineral media, while in bioventing oxygen was also added. The tests were carried out at controlled temperature of 25 ºC in stainless steel columns where the moist soil contaminated with benzene (200 mg per kg of soil occupied about 40% of the column’s volume. The processes were daily monitored in discontinued mode. Benzene concentration in the gas phase was quantified by gas chromatography (GC-FID, oxygen and carbon dioxide concentrations were monitored by respirometry. The results revealed that the three contaminated soils were remediated using both technologies, nevertheless, the bioventing showed faster rates. With this work it was proved that respirometric analysis is an appropriate instrument for monitoring the biological activity.

  19. Bioremediation of the textile waste effluent by Chlorella vulgaris

    OpenAIRE

    Hala Yassin El-Kassas; Laila Abdelfattah Mohamed

    2014-01-01

    The microalgae biomass production from textile waste effluent is a possible solution for the environmental impact generated by the effluent discharge into water sources. The potential application of Chlorella vulgaris for bioremediation of textile waste effluent (WE) was investigated using 22 Central Composite Design (CCD). This work addresses the adaptation of the microalgae C. vulgaris in textile waste effluent (WE) and the study of the best dilution of the WE for maximum biomass production...

  20. BIOREMEDIATION OF INDUSTRIAL AND MUNICIPAL WASTE WATER USING BACTERIAL ISOLATES

    OpenAIRE

    P.Priya darshini*, J.Sharpudin

    2016-01-01

    Bioremediation is a treatment that uses naturally occurring organisms to break down hazardous substances into less toxic or non toxic substances. The microbes are effective in control of pollution due to waste water. The industrial and municipal waste water is analyzed for different Physico-Chemical parameters such as pH, Temperature, TDS, BOD, COD, Total Alkalinity, Chlorides. The collected waste water samples were serially diluted and pour plated on Nutrient Agar medium and incubated at 37˚...

  1. Environmental Factors and Bioremediation of Xenobiotics Using White Rot Fungi

    OpenAIRE

    Magan, Naresh; Fragoeiro, Silvia; Bastos, Catarina

    2010-01-01

    This review provides background information on the importance of bioremediation approaches. It describes the roles of fungi, specifically white rot fungi, and their extracellular enzymes, laccases, ligninases, and peroxidises, in the degradation of xenobiotic compounds such as single and mixtures of pesticides. We discuss the importance of abiotic factors such as water potential, temperature, and pH stress when considering an environmental screening approach, and examples are provided of the ...

  2. Microbial Population Changes during Bioremediation of an Experimental Oil Spill

    OpenAIRE

    Macnaughton, Sarah J.; Stephen, John R.; Venosa, Albert D.; Davis, Gregory A.; Chang, Yun-juan; White, David C.

    1999-01-01

    Three crude oil bioremediation techniques were applied in a randomized block field experiment simulating a coastal oil spill. Four treatments (no oil control, oil alone, oil plus nutrients, and oil plus nutrients plus an indigenous inoculum) were applied. In situ microbial community structures were monitored by phospholipid fatty acid (PLFA) analysis and 16S rDNA PCR-denaturing gradient gel electrophoresis (DGGE) to (i) identify the bacterial community members responsible for the decontaminat...

  3. The bioremediation potential of marine sandy sediment microbiota

    OpenAIRE

    Dan Răzvan POPOVICIU

    2012-01-01

    The natural microbiota from marine sandy sediments on the Romanian sea coast was tested for resilience in case of hydrocarbon contamination, for estimating the number of (culturable) hydrocarbon and lipid oil-degrading microorganisms and for determining the influence of inorganic nitrate and phosphate nutrients on hydrocarbon spill bioremediation process, by microcosm experiments.Results show that hydrocarbon contamination affects the bacteriobenthos both in terms of cell numbers and composit...

  4. Bioremediation of severely weathered hydrocarbons: is it possible?

    Energy Technology Data Exchange (ETDEWEB)

    Gallego, J. R.; Villa, R.; Sierra, C.; Sotres, A.; Pelaez, A. I.; Sanchez, J.

    2009-07-01

    Weathering processes of spilled hydrocarbons promote a reduced biodegradability of petroleum compounds mixtures, and consequently bioremediation techniques are often ruled out within the selection of suitable remediation approaches. This is truly relevant wherever old spills at abandoned industrial sites have to be remediated. However it is well known most of the remaining fractions and individual compounds of weathered oil are still biodegradable, although at slow rates than alkanes or no and two-ring aromatics. (Author)

  5. Heavy Metal Polluted Soils: Effect on Plants and Bioremediation Methods

    OpenAIRE

    Chibuike, G. U.; S. C. Obiora

    2014-01-01

    Soils polluted with heavy metals have become common across the globe due to increase in geologic and anthropogenic activities. Plants growing on these soils show a reduction in growth, performance, and yield. Bioremediation is an effective method of treating heavy metal polluted soils. It is a widely accepted method that is mostly carried out in situ; hence it is suitable for the establishment/reestablishment of crops on treated soils. Microorganisms and plants employ different mechanisms for...

  6. Similar component analysis

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong; WANG Xin; LI Junwei; CAO Xianguang

    2006-01-01

    A new unsupervised feature extraction method called similar component analysis (SCA) is proposed in this paper. SCA method has a self-aggregation property that the data objects will move towards each other to form clusters through SCA theoretically,which can reveal the inherent pattern of similarity hidden in the dataset. The inputs of SCA are just the pairwise similarities of the dataset,which makes it easier for time series analysis due to the variable length of the time series. Our experimental results on many problems have verified the effectiveness of SCA on some engineering application.

  7. A case study of the intrinsic bioremediation of petroleum hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Barker, G.W.; Raterman, K.T.; Fisher, J.B.; Corgan, J.M. [and others

    1995-12-31

    Condensate liquids have been found to contaminate soil and groundwater at two gas production sites in the Denver Basin operated by Amoco Production Co. These sites have been closely monitored since July 1993 to determine whether intrinsic aerobic or anaerobic bioremediation of hydrocarbons occurs at a sufficient rate and to an adequate endpoint to support a no-intervention decision. Groundwater monitoring and analysis of soil cores suggest that intrinsic bioremediation is occurring at these sites by multiple pathways including aerobic oxidation, Fe{sup 3+} reduction, and sulfate reduction. In laboratory experiments the addition of gas condensate hydrocarbons to saturated soil from the gas production site stimulated sulfate reduction under anaerobic and oxygen-limiting conditions, and nitrate and Fe{sup 3+} reduction under oxygen-limiting conditions, compared to biotic controls that lacked hydrocarbon and sterile controls. The sulfate reduction corresponded to a reduction in the amount of toluene relative to other hydrocarbons. These results confirmed that subsurface soils at the gas production site have the potential for intrinsic bioremediation of hydrocarbons.

  8. Characterization of weathered petroleum hydrocarbons during a landfarming bioremediation study

    Directory of Open Access Journals (Sweden)

    Maletić Snežana

    2012-01-01

    Full Text Available Landfarming bioremediation was performed over 2 years on soil heavily polluted with weathered oil and oil derivatives: 23200 mg kg-1 of mineral oil, 35300 mg kg-1 total hydrocarbons, and 8.65 mg kg-1 of total PAHs. During the experiment, mineral oil, total hydrocarbon and PAH concentrations decreased by approximately 53%, 27% and 72%, respectively. A GC/MS-Scan was used to identify the crude oil components that persist after bioremediation treatment of contaminated soil and the metabolites generated during this process. The data shows that in weathered-hydrocarbons contaminated soil, the number of initially detected compounds after the bioremediation process further decreased over a 2 year period, and at the same time several new compounds were observed at the end of experiment. Higher persistence was also shown for heavier n-alkanes and branched alkanes, which could be detected over a longer period of time. The analysis highlights the importance of n-alkanes, their substituted derivatives and polycyclic aromatic hydrocarbons as the most significant pollutants.

  9. Bioremediation of Oil Spills in Cold Environments: A Review

    Institute of Scientific and Technical Information of China (English)

    YANG Si-Zhong; JIN Hui-Jun; WEI Zhi; HE Rui-Xia; JI Yan-Jun; LI Xiu-Mei; YU Shao-Peng

    2009-01-01

    Oil spills have become a serious problem in cold environments with the ever-increasing resource exploitation,transportation,storage,and accidental leakage of oil.Several techniques,including physical,chemical,and biological methods,are used to recover spilled oil from the environment.Bioremediation is a promising option for remediation since it is effective and economic in removing oil with less undue environmental damages.However,it is a relatively slow process in cold regions and the degree of success depends on a number of factors,including the properties and fate of oil spilled in cold environments,and the major microbial and environmental limitations of bioremediation.The microbial factors include bioavailability of hydrocarbons,mass transfer through the cell membrane,and metabolic limitations.As for the environmental limitations in the cold regions,the emphasis is on soil temperatures,freeze-thaw processes,oxygen and nutrients availability,toxicity,and electron acceptors.There have been several cases of success in the polar regions,particularly in the Arctic and sub-Arctic regions.However,the challenges and constraints for bioremediation in cold environments remain large.

  10. Challenging Oil Bioremediation at Deep-Sea Hydrostatic Pressure

    Science.gov (United States)

    Scoma, Alberto; Yakimov, Michail M.; Boon, Nico

    2016-01-01

    The Deepwater Horizon accident has brought oil contamination of deep-sea environments to worldwide attention. The risk for new deep-sea spills is not expected to decrease in the future, as political pressure mounts to access deep-water fossil reserves, and poorly tested technologies are used to access oil. This also applies to the response to oil-contamination events, with bioremediation the only (bio)technology presently available to combat deep-sea spills. Many questions about the fate of petroleum-hydrocarbons within deep-sea environments remain unanswered, as well as the main constraints limiting bioremediation under increased hydrostatic pressures and low temperatures. The microbial pathways fueling oil bioassimilation are unclear, and the mild upregulation observed for beta-oxidation-related genes in both water and sediments contrasts with the high amount of alkanes present in the spilled oil. The fate of solid alkanes (tar), hydrocarbon degradation rates and the reason why the most predominant hydrocarbonoclastic genera were not enriched at deep-sea despite being present at hydrocarbon seeps at the Gulf of Mexico have been largely overlooked. This mini-review aims at highlighting the missing information in the field, proposing a holistic approach where in situ and ex situ studies are integrated to reveal the principal mechanisms accounting for deep-sea oil bioremediation. PMID:27536290

  11. Microbial inoculants and fertilization for bioremediation of oil in wetlands

    International Nuclear Information System (INIS)

    Bioremediation is an attractive alternative to physical methods of oil spill cleanup in wetlands where the ecosystem can be easily damaged. Because populations of oil-degrading microorganisms are usually low in wetlands, there is potential for increasing bioremediation through bioaugmentation in conjunction with N and P supplementation. Eight microbial inoculant products were added to microcosms containing soil from a salt marsh. Four of these products were also used in mesocosms containing Spartina alterniflora grown in a glasshouse. In unfertilized microcosms, the extent of oil degraded as measured by carbon dioxide evolution during 90 days, was 30% higher in the product with the highest activity than was recorded in the control with oil by 36%. None of the products when added to the fertilized soil increased activity above that of the fertilized control with oil. Addition of oil to microcosms increased populations of hydrocarbon-degrading microorganisms, but bioaugmentation products did not increase populations. Neither addition of products nor fertilization enhanced the disappearance of oil in mesocosms in the glasshouse. Approximately 50% of the weathered oil disappeared in 41 d for all treatments. Because bioaugmentation did not enhance oil degradation, it seems that natural populations of hydrocarbon-degrading microorganisms were adequate in the salt marsh soil for bioremediation

  12. Gender similarities and differences.

    Science.gov (United States)

    Hyde, Janet Shibley

    2014-01-01

    Whether men and women are fundamentally different or similar has been debated for more than a century. This review summarizes major theories designed to explain gender differences: evolutionary theories, cognitive social learning theory, sociocultural theory, and expectancy-value theory. The gender similarities hypothesis raises the possibility of theorizing gender similarities. Statistical methods for the analysis of gender differences and similarities are reviewed, including effect sizes, meta-analysis, taxometric analysis, and equivalence testing. Then, relying mainly on evidence from meta-analyses, gender differences are reviewed in cognitive performance (e.g., math performance), personality and social behaviors (e.g., temperament, emotions, aggression, and leadership), and psychological well-being. The evidence on gender differences in variance is summarized. The final sections explore applications of intersectionality and directions for future research.

  13. Gender similarities and differences.

    Science.gov (United States)

    Hyde, Janet Shibley

    2014-01-01

    Whether men and women are fundamentally different or similar has been debated for more than a century. This review summarizes major theories designed to explain gender differences: evolutionary theories, cognitive social learning theory, sociocultural theory, and expectancy-value theory. The gender similarities hypothesis raises the possibility of theorizing gender similarities. Statistical methods for the analysis of gender differences and similarities are reviewed, including effect sizes, meta-analysis, taxometric analysis, and equivalence testing. Then, relying mainly on evidence from meta-analyses, gender differences are reviewed in cognitive performance (e.g., math performance), personality and social behaviors (e.g., temperament, emotions, aggression, and leadership), and psychological well-being. The evidence on gender differences in variance is summarized. The final sections explore applications of intersectionality and directions for future research. PMID:23808917

  14. Bioremediation of hydrocarbon polluted soil - Improvement of in situ bioremediation by bioaugmentation with endogenous and exogenous strains

    OpenAIRE

    Tarayre, Cédric

    2010-01-01

    Petroleum pollution has now become a real problem because hydrocarbons are persistent contaminants in soils and water. Contamination problems increase when ages of relevant facilities, such as oil storage tanks and pipelines, increase over time. The evolution of Legislation concerning soil pollution has led to the need of efficient techniques able to restore the polluted ground. Unfortunately, these techniques are expensive. Bioremediation of hydrocarbon polluted soils has been recognized as...

  15. Phylogenetic diversity of dominant bacterial communities during bioremediation of crude oil-polluted soil

    Directory of Open Access Journals (Sweden)

    Eugene Thomas Cloete

    2011-08-01

    degradation. Cluster analysis of DGGE bands using simple matching group average setting revealed that poultry droppings-amended soils and calcium ammonium nitrate-amended soils formed distinct clades meaning that the treatment selected similar bacterial populations for each of the treatments whereas NPK soils showed less association. Excision, reamplification and sequencing of dominant DGGE bands in biostimulated soils revealed the presence of distinct hydrocarbon degraders like Corynebacterium spp., Dietzia spp., low G+C Gram positive bacteria and some uncultured bacterial clones. Phylogenetic analysis of the 16S rRNA gene sequences of these dominant bacterial communities was conducted using the neighbour joining method of PHYLIP. Two distinct clades appeared in the tree clustered members of the Actinobacteria and Firmicutes separately. The overall data suggested that Gram positive bacteria especially members of the Actinobacteria may have a key role in bioremediation of crude oil-polluted soil.

  16. Cognitive residues of similarity

    OpenAIRE

    OToole, Stephanie; Keane, Mark T.

    2013-01-01

    What are the cognitive after-effects of making a similarity judgement? What, cognitively, is left behind and what effect might these residues have on subsequent processing? In this paper, we probe for such after-effects using a visual search task, performed after a task in which pictures of real-world objects were compared. So, target objects were first presented in a comparison task (e.g., rate the similarity of this object to another) thus, presumably, modifying some of their features befor...

  17. Biochar-carrying hydrocarbon decomposers promote degradation during the early stage of bioremediation

    Science.gov (United States)

    Galitskaya, Polina; Akhmetzyanova, Leisan; Selivanovskaya, Svetlana

    2016-10-01

    Oil pollution is one of the most serious current environmental problems. In this study, four strategies of bioremediation of oil-polluted soil were tested in the laboratory over a period of 84 days: (A) aeration and moistening; (B) amendment with 1 % biochar (w ⁄ w) in combination with A; amendment with 1 % biochar with immobilized Pseudomonas aeruginosa (C) or Acinetobacter radioresistens (D) in combination with A. All strategies used resulted in a decrease of the hydrocarbon content, while biochar addition (B, C, D strategies) led to acceleration of decomposition in the beginning. Microbial biomass and respiration rate increased significantly at the start of bioremediation. It was demonstrated that moistening and aeration were the main factors influencing microbial biomass, while implementation of biochar and introduction of microbes were the main factors influencing microbial respiration. All four remediation strategies altered bacterial community structure and phytotoxicity. The Illumina MiSeq method revealed 391 unique operational taxonomic units (OTUs) belonging to 40 bacterial phyla and a domination of Proteobacteria in all investigated soil samples. The lowest alpha diversity was observed in the samples with introduced bacteria on the first day of remediation. Metric multidimensional scaling demonstrated that in the beginning and at the end, microbial community structures were more similar than those on the 28th day of remediation. Strategies A and B decreased phytotoxicity of remediated soil between 2.5 and 3.1 times as compared with untreated soil. C and D strategies led to additional decrease of phytotoxicity between 2.1 and 3.2 times.

  18. The Qualitative Similarity Hypothesis

    Science.gov (United States)

    Paul, Peter V.; Lee, Chongmin

    2010-01-01

    Evidence is presented for the qualitative similarity hypothesis (QSH) with respect to children and adolescents who are d/Deaf or hard of hearing. The primary focus is on the development of English language and literacy skills, and some information is provided on the acquisition of English as a second language. The QSH is briefly discussed within…

  19. Similarity of molecular shape.

    Science.gov (United States)

    Meyer, A Y; Richards, W G

    1991-10-01

    The similarity of one molecule to another has usually been defined in terms of electron densities or electrostatic potentials or fields. Here it is expressed as a function of the molecular shape. Formulations of similarity (S) reduce to very simple forms, thus rendering the computerised calculation straightforward and fast. 'Elements of similarity' are identified, in the same spirit as 'elements of chirality', except that the former are understood to be variable rather than present-or-absent. Methods are presented which bypass the time-consuming mathematical optimisation of the relative orientation of the molecules. Numerical results are presented and examined, with emphasis on the similarity of isomers. At the extreme, enantiomeric pairs are considered, where it is the dissimilarity (D = 1 - S) that is of consequence. We argue that chiral molecules can be graded by dissimilarity, and show that D is the shape-analog of the 'chirality coefficient', with the simple form of the former opening up numerical access to the latter. PMID:1770379

  20. Profiling microbial community structures across six large oilfields in China and the potential role of dominant microorganisms in bioremediation.

    Science.gov (United States)

    Sun, Weimin; Li, Jiwei; Jiang, Lei; Sun, Zhilei; Fu, Meiyan; Peng, Xiaotong

    2015-10-01

    Successful bioremediation of oil pollution is based on a comprehensive understanding of the in situ physicochemical conditions and indigenous microbial communities as well as the interaction between microorganisms and geochemical variables. Nineteen oil-contaminated soil samples and five uncontaminated controls were taken from six major oilfields across different geoclimatic regions in China to investigate the spatial distribution of the microbial ecosystem. Microbial community analysis revealed remarkable variation in microbial diversity between oil-contaminated soils taken from different oilfields. Canonical correspondence analysis (CCA) further demonstrated that a suite of in situ geochemical parameters, including soil moisture and sulfate concentrations, were among the factors that influenced the overall microbial community structure and composition. Phylogenetic analysis indicated that the vast majority of sequences were related to the genera Arthrobacter, Dietzia, Pseudomonas, Rhodococcus, and Marinobacter, many of which contain known oil-degrading or oil-emulsifying species. Remarkably, a number of archaeal genera including Halalkalicoccus, Natronomonas, Haloterrigena, and Natrinema were found in relatively high abundance in some of the oil-contaminated soil samples, indicating that these Euryarchaeota may play an important ecological role in some oil-contaminated soils. This study offers a direct and reliable reference of the diversity of the microbial community in various oil-contaminated soils and may influence strategies for in situ bioremediation of oil pollution. PMID:26078113

  1. Bioremediation of polluted wasewaterwater influent: phiosphorus and nitrogen removal. Scientific Research and Essays

    DEFF Research Database (Denmark)

    Muchie, Mammo; Akpor, OB

    2010-01-01

    Akpor OB and Muchie M. (2010). Bioremediation of polluted wasewaterwater influent: phiosphorus and nitrogen removal. Scientific Research and Essays, Vol. 5(21), pp. 3222–3230......Akpor OB and Muchie M. (2010). Bioremediation of polluted wasewaterwater influent: phiosphorus and nitrogen removal. Scientific Research and Essays, Vol. 5(21), pp. 3222–3230...

  2. BIOREMEDIATION OF AN EXPERIMENTAL OIL SPILL ON THE SHORELINE OF DELAWARE BAY

    Science.gov (United States)

    In the summer of 1994, a field study was undertaken in Delaware in which light crude oil was intentionally released onto plots to evaluate bioremediation. The objectives were to obtain credible statistical evidence to determine if bioremediation with inorganic mineral nutrients ...

  3. Bioremediation techniques-classification based on site of application: principles, advantages, limitations and prospects.

    Science.gov (United States)

    Azubuike, Christopher Chibueze; Chikere, Chioma Blaise; Okpokwasili, Gideon Chijioke

    2016-11-01

    Environmental pollution has been on the rise in the past few decades owing to increased human activities on energy reservoirs, unsafe agricultural practices and rapid industrialization. Amongst the pollutants that are of environmental and public health concerns due to their toxicities are: heavy metals, nuclear wastes, pesticides, green house gases, and hydrocarbons. Remediation of polluted sites using microbial process (bioremediation) has proven effective and reliable due to its eco-friendly features. Bioremediation can either be carried out ex situ or in situ, depending on several factors, which include but not limited to cost, site characteristics, type and concentration of pollutants. Generally, ex situ techniques apparently are more expensive compared to in situ techniques as a result of additional cost attributable to excavation. However, cost of on-site installation of equipment, and inability to effectively visualize and control the subsurface of polluted sites are of major concerns when carrying out in situ bioremediation. Therefore, choosing appropriate bioremediation technique, which will effectively reduce pollutant concentrations to an innocuous state, is crucial for a successful bioremediation project. Furthermore, the two major approaches to enhance bioremediation are biostimulation and bioaugmentation provided that environmental factors, which determine the success of bioremediation, are maintained at optimal range. This review provides more insight into the two major bioremediation techniques, their principles, advantages, limitations and prospects. PMID:27638318

  4. Limiting Similarity Revisited

    OpenAIRE

    Szabo, P; Meszena, G.

    2005-01-01

    We reinvestigate the validity of the limiting similarity principle via numerical simulations of the Lotka-Volterra model. A Gaussian competition kernel is employed to describe decreasing competition with increasing difference in a one-dimensional phenotype variable. The simulations are initiated by a large number of species, evenly distributed along the phenotype axis. Exceptionally, the Gaussian carrying capacity supports coexistence of all species, initially present. In case of any other, d...

  5. Compression-based similarity

    OpenAIRE

    Vitányi, Paul

    2011-01-01

    First we consider pair-wise distances for literal objects consisting of finite binary files. These files are taken to contain all of their meaning, like genomes or books. The distances are based on compression of the objects concerned, normalized, and can be viewed as similarity distances. Second, we consider pair-wise distances between names of objects, like "red" or "christianity." In this case the distances are based on searches of the Internet. Such a search can be performed by any search...

  6. Variably saturated flow and multicomponent biogeochemical reactive transport modeling of a uranium bioremediation field experiment.

    Science.gov (United States)

    Yabusaki, Steven B; Fang, Yilin; Williams, Kenneth H; Murray, Christopher J; Ward, Andy L; Dayvault, Richard D; Waichler, Scott R; Newcomer, Darrell R; Spane, Frank A; Long, Philip E

    2011-11-01

    Three-dimensional, coupled variably saturated flow and biogeochemical reactive transport modeling of a 2008 in situ uranium bioremediation field experiment is used to better understand the interplay of transport and biogeochemical reactions controlling uranium behavior under pulsed acetate amendment, seasonal water table variation, spatially variable physical (hydraulic conductivity, porosity) and geochemical (reactive surface area) material properties. While the simulation of the 2008 Big Rusty acetate biostimulation field experiment in Rifle, Colorado was generally consistent with behaviors identified in previous field experiments at the Rifle IFRC site, the additional process and property detail provided several new insights. A principal conclusion from this work is that uranium bioreduction is most effective when acetate, in excess of the sulfate-reducing bacteria demand, is available to the metal-reducing bacteria. The inclusion of an initially small population of slow growing sulfate-reducing bacteria identified in proteomic analyses led to an additional source of Fe(II) from the dissolution of Fe(III) minerals promoted by biogenic sulfide. The falling water table during the experiment significantly reduced the saturated thickness of the aquifer and resulted in reactants and products, as well as unmitigated uranium, in the newly unsaturated vadose zone. High permeability sandy gravel structures resulted in locally high flow rates in the vicinity of injection wells that increased acetate dilution. In downgradient locations, these structures created preferential flow paths for acetate delivery that enhanced local zones of TEAP reactivity and subsidiary reactions. Conversely, smaller transport rates associated with the lower permeability lithofacies (e.g., fine) and vadose zone were shown to limit acetate access and reaction. Once accessed by acetate, however, these same zones limited subsequent acetate dilution and provided longer residence times that resulted

  7. Bioremediation of PAHs and VOCs: Advances in clay mineral-microbial interaction.

    Science.gov (United States)

    Biswas, Bhabananda; Sarkar, Binoy; Rusmin, Ruhaida; Naidu, Ravi

    2015-12-01

    Bioremediation is an effective strategy for cleaning up organic contaminants, such as polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs). Advanced bioremediation implies that biotic agents are more efficient in degrading the contaminants completely. Bioremediation by microbial degradation is often employed and to make this process efficient, natural and cost-effective materials can serve as supportive matrices. Clay/modified clay minerals are effective adsorbents of PAHs/VOCs, and readily available substrate and habitat for microorganisms in the natural soil and sediment. However, the mechanism underpinning clay-mediated biodegradation of organic compounds is often unclear, and this requires critical investigation. This review describes the role of clay/modified clay minerals in hydrocarbon bioremediation through interaction with microbial agents in specific scenarios. The vision is on a faster, more efficient and cost-effective bioremediation technique using clay-based products. This review also proposes future research directions in the field of clay modulated microbial degradation of hydrocarbons.

  8. CHARACTERIZATION OF POLYLACTIC ACID COLLOIDS FOR IN SITU BIOREMEDIATION

    Energy Technology Data Exchange (ETDEWEB)

    Ashley N. Westbrook

    2003-07-01

    Groundwater contamination is a widespread problem. As human activities generate chemical wastes, we seek quick, yet not always environmentally friendly, ways to dispose of them. Often, chemicals are dumped into waste containers and buried. Unfortunately, these chemicals may spill or leak, seep deeper into the ground, and eventually reach groundwater. Chlorinated organic solvents such as trichloroethene, tetrachloroethane, and chloroform are common contaminants in groundwater [1]. These solvents originate from chemical spills, tank leaks, and waste disposal practices [2]. Such contaminants are harmful to humans, and need to be removed to restore clean groundwater. There are two types of methods to clean chemically contaminated soil and groundwater: ex situ and in situ. Both types have advantages and disadvantages. In situ remediation avoids the cost of removing the contaminated material and has a lower risk of worker exposure to the contaminants. One in situ technique that shows promise is remediation, which uses microorganisms to anaerobically degrade contaminants. In bioremediation in situ, the microorganisms that are already present in the ground utilize nutrients that are injected into the ground to metabolize the contaminants into nonhazardous materials. The nutrients serve as a carbon source for the microbes. Though this method has been used with some success, there have been problems with too rapid release of nutrients to the microbes. In these cases, the microbes multiplied too rapidly and caused biofouling. This can occur when the nutrient content of the bioremediation solution is too high, as when lactate or lactic acid is the nutrient. Lactic acid is typically produced in carbohydrate matter by fermentation, and is used mainly in the food and pharmaceutical industries [3]. Because it has been found difficult to uniformly distribute lactate solutions in a contaminated area due to biofouling, it was suggested that polylactic acid, in colloidal form, be used

  9. In situ bioremediation strategies for oiled shoreline environments

    International Nuclear Information System (INIS)

    Despite advances in preventative measures, recent events have demonstrated that accidental oil spills at sea will still occur. While physical (e.g. booms and skimmers) and chemical (e.g. chemical dispersants) methods have been developed to recover and/or disperse oil spilled at sea, they are not 100% effective and are frequently limited by operational constraints attributed to sea state and/or nature of the contamination. As a result, oil spills frequently impact shoreline environments. In situ bioremediation, the addition of substances or modification of habitat at contaminated sites to accelerate natural biodegradation processes, is now recognised as an alternative spill response technology of the remediation of these sites. Recommended for use following the physical removal of bulk oil, this treatment strategy has an operational advantage in that it breaks down and/or removes the residual contamination in place. Laboratory experiments and field trials have demonstrated the feasibility and success of bioremediation strategies such as nutrient enrichment to enhance bacterial degradation of oil on cobble, sand beach and salt marsh environments. With improved knowledge of the factors that limit natural oil degradation rates, the feasibility of other strategies such as phytoremediation, enhanced oil-mineral fines interaction and the addition of oxygen or alternative electron acceptors are now being evaluated. Laboratory and field test protocols are being refined for the selection of effective bioremediation agents and methods of application. It is recommended that future operational guidelines include real time product efficacy test and environmental effects monitoring programs. Termination of treatment should be implemented when: 1) it is no longer effective; 2) the oil has degraded to acceptable biologically benign concentrations; or 3) toxicity due to the treatment is increasing. (Author)

  10. Integrated green algal technology for bioremediation and biofuel.

    Science.gov (United States)

    Sivakumar, Ganapathy; Xu, Jianfeng; Thompson, Robert W; Yang, Ying; Randol-Smith, Paula; Weathers, Pamela J

    2012-03-01

    Sustainable non-food energy biomass and cost-effective ways to produce renewable energy technologies from this biomass are continuously emerging. Algae are capable of producing lipids and hydrocarbons quickly and their photosynthetic abilities make them a promising candidate for an alternative energy source. In addition, their favorable carbon life cycle and a renewed focus on rural economic development are attractive factors. In this review the focus is mainly on the integrated approach of algae culture for bioremediation and oil-based biofuel production with mention of possible other value-added benefits of using algae for those purposes. PMID:22230775

  11. Ex-situ bioremediation of petroleum contaminated soil

    International Nuclear Information System (INIS)

    The use of stress acclimated bacteria and nutrient supplements to enhance the biodegradation of petroleum contaminated soil can be a cost effective and reliable treatment technology to reduce organic contaminant levels to below established by local, state, and federal regulatory clean-up criteria. This paper will summarize the results of a field study in which 12,000 yds3 of petroleum contaminated soil was successfully treated via ex-situ bioremediation and through management of macro and micronutrient concentrations, as well as, other site specific environmental factors that are essential for optimizing microbial growth

  12. Aerobic bioremediation of petroleum contaminated soil using controlled landfarming technology

    International Nuclear Information System (INIS)

    This paper reports that the Delaware Department of Natural Resources and Environmental Control (DNREC) has been concerned about open, uncontrolled landfarming remediation procedures producing a significant amount of atmospheric volatile petroleum discharge and increasing the probability of the remediation site's soil and groundwater becoming contaminated by rainwater. WIK Associates, Inc., therefore, has been developing full scale aerobic bioremediation technology for clients within the Delaware area in order to carry out year round, full scale, aerobic biodegradation of petroleum contaminated soils, while controlling any volatile emissions

  13. Throw it overboard: a commentary on coastal pollution and bioremediation

    OpenAIRE

    Charlier, R.H.; Finkl, C.W.; Krystosyk-Gromadzinska, A.

    2012-01-01

    Charlier, R.H.; Finkl, C.W., and Krystosyk-Gromadzinska, A. 2012. Throw it Overboard: A Commentary on Coastal Pollution and Bioremediation. Journal of Coastal Research, 28(4), 881-890. West Palm Beach (Florida), ISSN 0749-0208.The belief that rivers and oceans cleaned themselves faded as humanity expanded and wastes took on an ever more diversified character. The pollution of waterways, bays, inlets, and gulfs made many of them unusable for water transport. The solution commonly applied is to...

  14. Conceptualizing "suicidal genetically engineered microorganisms" for bioremediation applications.

    Science.gov (United States)

    Pandey, Gunjan; Paul, Debarati; Jain, Rakesh K

    2005-02-18

    Use of genetically modified microorganisms (GEMs) for pollution abatement has been limited because of risks associated with their release in the environment. Recent developments in the area of recombinant DNA technologies have paved the way for conceptualizing "suicidal genetically engineered microorganisms" (S-GEMS) to minimize such anticipated hazards and to achieve efficient and safer bioremediation of contaminated sites. Our strategy of designing a novel S-GEM is based on the knowledge of killer-anti-killer gene(s) that would be susceptible to programmed cell death after detoxification of any given contaminated site(s). PMID:15649393

  15. In situ bioremediation of oil pollution in the unsaturated zone

    International Nuclear Information System (INIS)

    Leakage of an underground storage tank at the Trandum Army Base caused a 20.000 liter spill of fuel oil. Several options for remediation have been evaluated. In situ bioremediation was chosen as the most cost effective and realistic method and was evaluated in detail. Preliminary laboratory studies showed that a large number of hydrocarbon degrading micro-organism are present and that good degradation rates can be obtained with the addition of a nitrogen and phosphorus source. Since July 1991 a full scale bioventing installation has been in operation. The preliminary monitoring results give an indication of biological activity. 8 refs., 6 figs., 2 tabs

  16. Mechanisms for similarity matching in disparity measurement

    Directory of Open Access Journals (Sweden)

    Ross eGoutcher

    2014-01-01

    Full Text Available Early neural mechanisms for the measurement of binocular disparity appear to operate in a manner consistent with cross-correlation-like processes. Consequently, cross-correlation, or cross-correlation-like procedures have been used in a range of models of disparity measurement. Using such procedures as the basis for disparity measurement creates a preference for correspondence solutions that maximise the similarity between local left and right eye image regions. Here, we examine how observers’ perception of depth in an ambiguous stereogram is affected by manipulations of luminance and orientation-based image similarity. Results show a strong effect of coarse-scale luminance similarity manipulations, but a relatively weak effect of finer-scale manipulations of orientation similarity. This is in contrast to the measurements of depth obtained from a standard cross-correlation model. This model shows strong effects of orientation similarity manipulations and weaker effects of luminance similarity. In order to account for these discrepancies, the standard cross-correlation approach may be modified to include an initial spatial frequency filtering stage. The performance of this adjusted model most closely matches human psychophysical data when spatial frequency filtering favours coarser scales. This is consistent with the operation of disparity measurement processes where spatial frequency and disparity tuning are correlated, or where disparity measurement operates in a coarse-to-fine manner.

  17. Similar dissection of sets

    CERN Document Server

    Akiyama, Shigeki; Okazaki, Ryotaro; Steiner, Wolfgang; Thuswaldner, Jörg

    2010-01-01

    In 1994, Martin Gardner stated a set of questions concerning the dissection of a square or an equilateral triangle in three similar parts. Meanwhile, Gardner's questions have been generalized and some of them are already solved. In the present paper, we solve more of his questions and treat them in a much more general context. Let $D\\subset \\mathbb{R}^d$ be a given set and let $f_1,...,f_k$ be injective continuous mappings. Does there exist a set $X$ such that $D = X \\cup f_1(X) \\cup ... \\cup f_k(X)$ is satisfied with a non-overlapping union? We prove that such a set $X$ exists for certain choices of $D$ and $\\{f_1,...,f_k\\}$. The solutions $X$ often turn out to be attractors of iterated function systems with condensation in the sense of Barnsley. Coming back to Gardner's setting, we use our theory to prove that an equilateral triangle can be dissected in three similar copies whose areas have ratio $1:1:a$ for $a \\ge (3+\\sqrt{5})/2$.

  18. Spatial planning

    OpenAIRE

    Dimitrov, Nikola; Koteski, Cane

    2016-01-01

    The professional book ,, Space planning "processed chapters on: space, concept and definition of space, space as a system, spatial economics, economic essence of space, space planning, social determinants of spatial planning, spatial planning as a process, factors development and elements in spatial planning, methodology, components and content of spatial planning stages and types of preparation of spatial planning, spatial planning and industrialization, industrialization, urbanization and s...

  19. Self-similar parabolic plasmonic beams.

    Science.gov (United States)

    Davoyan, Arthur R; Turitsyn, Sergei K; Kivshar, Yuri S

    2013-02-15

    We demonstrate that an interplay between diffraction and defocusing nonlinearity can support stable self-similar plasmonic waves with a parabolic profile. Simplicity of a parabolic shape combined with the corresponding parabolic spatial phase distribution creates opportunities for controllable manipulation of plasmons through a combined action of diffraction and nonlinearity.

  20. Self Similar Optical Fiber

    Science.gov (United States)

    Lai, Zheng-Xuan

    This research proposes Self Similar optical fiber (SSF) as a new type of optical fiber. It has a special core that consists of self similar structure. Such a structure is obtained by following the formula for generating iterated function systems (IFS) in Fractal Theory. The resulted SSF can be viewed as a true fractal object in optical fibers. In addition, the method of fabricating SSF makes it possible to generate desired structures exponentially in numbers, whereas it also allows lower scale units in the structure to be reduced in size exponentially. The invention of SSF is expected to greatly ease the production of optical fiber when a large number of small hollow structures are needed in the core of the optical fiber. This dissertation will analyze the core structure of SSF based on fractal theory. Possible properties from the structural characteristics and the corresponding applications are explained. Four SSF samples were obtained through actual fabrication in a laboratory environment. Different from traditional conductive heating fabrication system, I used an in-house designed furnace that incorporated a radiation heating method, and was equipped with automated temperature control system. The obtained samples were examined through spectrum tests. Results from the tests showed that SSF does have the optical property of delivering light in a certain wavelength range. However, SSF as a new type of optical fiber requires a systematic research to find out the theory that explains its structure and the associated optical properties. The fabrication and quality of SSF also needs to be improved for product deployment. As a start of this extensive research, this dissertation work opens the door to a very promising new area in optical fiber research.

  1. The phage-driven microbial loop in petroleum bioremediation.

    Science.gov (United States)

    Rosenberg, Eugene; Bittan-Banin, Gili; Sharon, Gil; Shon, Avital; Hershko, Galit; Levy, Itzik; Ron, Eliora Z

    2010-07-01

    During the drilling process and transport of crude oil, water mixes with the petroleum. At oil terminals, the water settles to the bottom of storage tanks. This drainage water is contaminated with emulsified oil and water-soluble hydrocarbons and must be treated before it can be released into the environment. In this study, we tested the efficiency of a continuous flow, two-stage bioreactor for treating drainage water from an Israeli oil terminal. The bioreactor removed all of the ammonia, 93% of the sulfide and converted 90% of the total organic carbon (TOC) into carbon dioxide. SYBR Gold staining indicated that reactor 1 contained 1.7 × 10(8) bacteria and 3.7 × 10(8) phages per millilitre, and reactor 2 contained 1.3 × 10(8) bacteria and 1.7 × 10(9) phages per millilitre. The unexpectedly high mineralization of TOC and high concentration of phage in reactor 2 support the concept of a phage-driven microbial loop in the bioremediation of the drainage water. In general, application of this concept in bioremediation of contaminated water has the potential to increase the efficiency of processes. PMID:21255344

  2. Transformation of a petroleum pollutant during soil bioremediation experiments

    Directory of Open Access Journals (Sweden)

    B. JOVANCICEVIC

    2008-05-01

    Full Text Available The experiment of ex situ soil bioremediation was performed at the locality of the Oil Refinery in Pančevo (alluvial formation of the Danube River, Serbia polluted with an oil type pollutant. The experiments of biostimulation, bioventilation and reinoculation of an autochthonous microbial consortium were performed during the six-month period (May–November 2006. The changes in the quantity and composition of the pollutant, or the bioremediation effect, were monitored by analysis of the samples of the polluted soil taken in time spans of two weeks. In this way, from the beginning until the end of the experiment, 12 samples were collected and marked as P1–P12 (Pančevo 1–Pančevo 12. The results obtained showed that more significant changes in the composition of the oil pollutant occurred only during the last phases of the experiment (P8–P12. The activity of microorganisms was reflected in the increase of the quantity of polar oil fractions, mainly fatty acid fractions. In this way, the quantity of total eluate increased, and the quantity of the insoluble residue was reduced to a minimum, whereby the oil pollutant was transformed to a form that could be removed more efficiently and more completely from the soil, as a segment of the environment.

  3. Bioremediation of petrochemical sludge from oil refining operations

    International Nuclear Information System (INIS)

    Petroleum refineries have historically produced large quantities of hydrocarbon sludge as a waste product. A common past practice for disposal of this material was to deposit it in open pits. These hazardous waste sites now require remediation to meet current environmental regulations. This report will present data from a feasibility study on bioremediation for one such site. Data will be presented on the characteristics and composition of the crude sludge including organic analysis by GC/MS techniques, loss on ignition, TOC pH, oil and grease levels, metals content by atomic adsorption and bacteria plate counts. The effectiveness of bioremediation will be examined using data from shaker flask studies with indigenous and other bacteria sources. Key parameters being monitored will include toxicity using a Microtox assay, oil and grease levels, and the concentration of individual chemical species using GC/MS analysis. Biological data such as bacteria growth rates and nutrient uptake rates will also be presented and compared to biodegradation rates

  4. Degrading and Detoxifying Industrial Waste Water using Bioremediation Approach

    Directory of Open Access Journals (Sweden)

    P. K. Agrawal

    2014-06-01

    Full Text Available Bioremediation uses various microorganisms to detoxify or degrade various harmful substances in the nature, particularly soil and water. In the proposed work, five species of micro-organisms were used to analyse their impact on various physico-chemical parameters of water. In the first attempt the actual physico chemical parameters of the collected sample water were noted down (Fresh sample parameters. Then the sample water was treated with micro-organisms (one at a time. The growth of microbes was noted carefully over 96 hours after inoculation. The physico chemical parameters were recorded again and were compared with the fresh sample parameters. The results were analysed for any change and on this basis an impact factor was developed. The study reveals all the selected microbes have a great capacity of degrading and simplifying the complex molecules into simpler ones. Bioremediative treatment further enhances this capacity and therefore this approach can be utilized on large scale to minimize pollution of water bodies.

  5. Microbial Bioremediation of Fuel Oil Hydrocarbons in Marine Environment

    Directory of Open Access Journals (Sweden)

    Sapna Pavitran

    2006-04-01

    Full Text Available Pollution in marine environment due to heavier petroleum products such as high-speeddiesel is known to take from days to months for complete natural remediation owing to its lowvolatility. For the survival of marine flora and fauna, it is important to control pollution causedby such recalcitrant and xenobiotic substances. Several petroleum hydrocarbons found in natureare toxic and recalcitrant. Therefore, pollution due to high-speed diesel is a cause of concern.The natural dispersion of high-speed diesel, a slow process, is attributed to an overall combinedeffect of physico-chemical and biological processes which take months for complete dispersion.History of marine oil spill bioremediation indicates limited laboratory studies. But experiencesfrom various oil spill management and field trials indicate important role of bioremediation, where,biodegradation of hydrocarbons through microbial mediators plays a major role in pollutant oildispersion. These microbial mediators such as bioemulsifiers and fimbrae, help in emulsification,dispersion, allowing attachment of bacteria to oil layers, followed by substrate-specific enzymaticbiodegradation in water.

  6. In situ petroleum hydrocarbon bioremediation in the Canadian Arctic

    Energy Technology Data Exchange (ETDEWEB)

    Greer, C.; Bell, T.; Lee, K.; Delisle, S.; Kovanen, D.; Craig, D.; Juck, D. [National Research Council of Canada, Montreal, PQ (Canada). Biotechnology Research Inst.

    2010-07-01

    This presentation reported on the in-situ bioremediation of diesel contaminated soils at the Canadian Forces Station CFS-Alert, in the Arctic. The soil was amended with monoammonium phosphate (MAP). The operation was designed to take place in a 2 month period during the brief thaw season. This presentation described the installation of the bioventing stacks, the turning of soil, and the application of an oxygen release compound (ORC) at the surface of the permafrost. A significant decrease in petroleum hydrocarbons (PC) was noted over 2 months. The effect of MAP amendment was a slight decrease in biomass in the pristine environment and a significant increase in biomass in the contaminated environment. The alkB gene was found to be important in the biodegradation of alkanes. Stable isotope probing (SIP) was used to identify active organisms. This bioremediation study showed that even in harsh Arctic climates, soils that are moderately contaminated with petroleum hydrocarbons can be remediated effectively and economically via biodegradation. tabs., figs.

  7. Bioremediation of Pyrene-Contaminated Soils Using Biosurfactant

    Directory of Open Access Journals (Sweden)

    Jorfi

    2014-10-01

    Full Text Available Background Polycyclic aromatic hydrocarbons (PAHs are persistence organic chemicals with proved carcinogenic and mutagenic hazards. These compounds are usually adsorbed in soils in vicinity of oil and gas industries. Bioremediation of PAHs contaminated soils is difficult due to hydrophobic nature of PAHs. Objectives The main purpose of the current study was to determine the pyrene removal efficiency in synthetically contaminated soil, using biosurfactant. Materials and Methods Four pure bacterial strains capable of pyrene degradation were isolated from contaminated soils via enrichment techniques. The soil samples were spiked with an initial pyrene concentration of 500 mg/kg and subjected to bioremediation using a mixed culture comprised of previously isolated strains, in addition to application of biosurfactant during 63 days. Results The pyrene removal efficiency in samples containing biosurfactant, without biosurfactant and controls, were 86.4%, 59.8% and 14%, respectively, after 63 days. The difference of pyrene removal efficiency between the biosurfactant-containing samples and the ones without it was significant (P < 0.05. Conclusions Application of rhamnolipid biosurfactant produced by Pseudomonas aeruginosa significantly improved pyrene removal in contaminated soils.

  8. Bioremediation of oil spills in the United States

    International Nuclear Information System (INIS)

    The involvement of EPA in the cleanup of oil-contaminated beaches in Prince William Sound, Alaska, following the Exxon Valdez oil spill, has generated a significant research effort in oil spill cleanup technology within EPA's Office of Research and Development. Because of the successful use of bioremediation in the Alaskan spill, a considerable portion of the research has been directed toward its further development, particularly as it might apply to other types of beaches and open water. In hindsight the problems faced in the application of bioremediation on the beaches of Prince William Sound appear relatively straightforward. First, the major obstacle of logistics on remote beaches was effectively overcome by using the operational capabilities created by the massive physical washing operation conducted from barges. Second, oil-degrading microbial communities were rapidly enriched in the oil-contaminated beach material, including subsurface, thereby precluding the need for any inoculation procedures. This situation, however, created a significant increased demand for nitrogen and phosphorus nutrients that was met through the application of commercially available fertilizers. Natural biodegradation of the oil was enhanced by the addition of fertilizer, substantially aiding in the overall cleanup operation. Third, the extremely high porosity of the cobblestone and mixed sand and gravel beach material allowed oil to be spread over a large surface area, thereby improving availability to the oil-degrading microbial communities and allowing, through tidal and wave action, the constant replenishment of oxygen. In addition, it created a high dilution capability that effectively prevented the accumulation of ammonia

  9. Bioremediation potential of crude oil spilled on soil

    International Nuclear Information System (INIS)

    Spills sometimes occur during routine operations associated with exploration and production (E and P) of crude oil. These spills at E and P sites typically are small, less than 1 acre (0.4 ha), and the spill may be in remote locations. As a result, bioremediation often represents a cost-effective alternative to other cleanup technologies. The goal of this study was to determine the potential for biodegrading a range of crude oil types and determining the effect of process variables such as soil texture and soil salinity. Crude oils evaluated ranged in American Petroleum institute (API) gravity from 14 degree to 45 degree. The extent of biodegradation was calculated from oxygen uptake data and the total extractable material (TEM) concentration. Based on the data collected, a simple model was developed for predicting the bioremediation potential of a range of crude oil types. Biodegradation rates were significantly lower in sandy soils. Soil salinities greater than approximately 40 mmhos/cm adversely impacted soil microbial activity and biodegradation rate

  10. Influence of salinity on bioremediation of oil in soil

    International Nuclear Information System (INIS)

    Spills from oil production and processing result in soils being contaminated with oil and salt. The effect of NaCl on degradation of oil in a sandy-clay loam and a clay loam soil was determined. Soils were treated with 50 g kg-1 non-detergent motor oil (30 SAE). Salt treatments included NaCl amendments to adjust the soil solution electrical conductivities to 40, 120, and 200 dS m-1. Soils were amended with nutrients and incubated at 25oC. Oil degradation was estimated from the quantities of CO2 evolved and from gravimetric determinations of remaining oil. Salt concentrations of 200 dS m-1 in oil amended soils resulted in a decrease in oil mineralized by 44% for a clay loam and 20% for a sandy-clay loam soil. A salt concentration of 40 dS m-1 reduced oil mineralization by about 10% in both soils. Oil mineralized in the oil amended clay-loam soil was 2-3 times greater than for comparable treatments of the sandy-clay loam soil. Amending the sandy-clay loam soil with 5% by weight of the clay-loam soil enhanced oil mineralization by 40%. Removal of salts from oil and salt contaminated soils before undertaking bioremediation may reduce the time required for bioremediation. (author)

  11. Laboratory studies of oil spill bioremediation; toward understanding field behavior

    International Nuclear Information System (INIS)

    Oil spill remediation aims to enhance the natural process of microbial hydrocarbon biodegradation. The microbial foundations have been studied throughout this century, but the focus of most of this work has been on the degradation of well defined compounds by well defined microbial species. This paper addresses laboratory studies on crude oil biodegradation by microbial consortia obtained from oiled beaches in Prince William Sound, Alaska following the spill from the Exxon Valdez. It demonstrates that oil degradation is indeed likely to be nitrogen-limited in Prince William Sound, the different molecular classes in crude oil that are subjected to biodegradation, the identification of conserved species in the oil that can be used for assessing biodegradation and bioremediation in the field, the effectiveness of fertilizers in stimulating sub-surface biodegradation, the role of the olephilic fertilizer Inipol EAP22, and the identification of the oil-degrading microorganisms in Prince William Sound. Together, these laboratory studies provided guidance and important insights into the microbial phenomena underlying the successful bioremediation of the oiled shorelines

  12. Bioremediation of zirconium from aqueous solution by coriolus versicolor: process optimization

    International Nuclear Information System (INIS)

    In the present study the potential of live mycelia of Coriolus versicolor was explored for the removal of zirconium from simulated aqueous solution. Optimum experimental parameters for the bioremediation of zirconium using C. versicolor biomass have been investigated by studying the effect of mycelia dose, concentration of zirconium, contact time and temperature. The isothermal studies indicated that the ongoing bioremediation process was exothermic in nature and obeyed Langmuir adsorption isotherm model. The Gibbs free energy (ΔG), entropy (ΔS) and enthalpy (ΔH) of bioremediation were also determined. The result showed that bioremediation of zirconium by live C. versicolor was feasible and spontaneous at room temperature. The equilibrium data verified the involvement of chemisorption during the bioremediation. The kinetic data indicated the operation of pseudo-second order process during the biosorption of zirconium from aqueous solution. Maximum bioremediation capacity (110.75 mg/g) of C. versicolor was observed under optimum operational conditions: pH 4.5, biomass dose 0.05 mg/100 mL, contact time 6 h and temperature 30 degree C. The results showed that C. versicolor could be used for bioremediation of heavy metal ions from aqueous systems. (author)

  13. Bioremediation of multi-polluted soil by spent mushroom (Agaricus bisporus) substrate: Polycyclic aromatic hydrocarbons degradation and Pb availability.

    Science.gov (United States)

    García-Delgado, Carlos; Yunta, Felipe; Eymar, Enrique

    2015-12-30

    This study investigates the effect of three spent Agaricus bisporus substrate (SAS) application methods on bioremediation of soil multi-polluted with Pb and PAH from close to a shooting range with respect natural attenuation (SM). The remediation treatments involve (i) use of sterilized SAS to biostimulate the inherent soil microbiota (SSAS) and two bioaugmentation possibilities (ii) its use without previous treatment to inoculate A. bisporus and inherent microbiota (SAS) or (iii) SAS sterilization and further A. bisporus re-inoculation (Abisp). The efficiency of each bioremediation microcosm was evaluated by: fungal activity, heterotrophic and PAH-degrading bacterial population, PAH removal, Pb mobility and soil eco-toxicity. Biostimulation of the native soil microbiology (SSAS) achieved similar levels of PAH biodegradation as SM and poor soil detoxification. Bioaugmented microcosms produced higher PAH removal and eco-toxicity reduction via different routes. SAS increased the PAH-degrading bacterial population, but lowered fungal activity. Abisp was a good inoculum carrier for A. bisporus exhibiting high levels of ligninolytic activity, the total and PAH-degrading bacteria population increased with incubation time. The three SAS applications produced slight Pb mobilization (<0.3%). SAS sterilization and further A. bisporus re-inoculation (Abisp) proved the best application method to remove PAH, mainly BaP, and detoxify the multi-polluted soil. PMID:26188871

  14. Bioremediation of multi-polluted soil by spent mushroom (Agaricus bisporus) substrate: Polycyclic aromatic hydrocarbons degradation and Pb availability.

    Science.gov (United States)

    García-Delgado, Carlos; Yunta, Felipe; Eymar, Enrique

    2015-12-30

    This study investigates the effect of three spent Agaricus bisporus substrate (SAS) application methods on bioremediation of soil multi-polluted with Pb and PAH from close to a shooting range with respect natural attenuation (SM). The remediation treatments involve (i) use of sterilized SAS to biostimulate the inherent soil microbiota (SSAS) and two bioaugmentation possibilities (ii) its use without previous treatment to inoculate A. bisporus and inherent microbiota (SAS) or (iii) SAS sterilization and further A. bisporus re-inoculation (Abisp). The efficiency of each bioremediation microcosm was evaluated by: fungal activity, heterotrophic and PAH-degrading bacterial population, PAH removal, Pb mobility and soil eco-toxicity. Biostimulation of the native soil microbiology (SSAS) achieved similar levels of PAH biodegradation as SM and poor soil detoxification. Bioaugmented microcosms produced higher PAH removal and eco-toxicity reduction via different routes. SAS increased the PAH-degrading bacterial population, but lowered fungal activity. Abisp was a good inoculum carrier for A. bisporus exhibiting high levels of ligninolytic activity, the total and PAH-degrading bacteria population increased with incubation time. The three SAS applications produced slight Pb mobilization (soil.

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

    Energy Technology Data Exchange (ETDEWEB)

    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. Hydrogeophysical imaging of deposit heterogeneity and groundwater chemistry changes during DNAPL source zone bioremediation

    Science.gov (United States)

    Chambers, J. E.; Wilkinson, P. B.; Wealthall, G. P.; Loke, M. H.; Dearden, R.; Wilson, R.; Allen, D.; Ogilvy, R. D.

    2010-10-01

    Robust characterization and monitoring of dense nonaqueous phase liquid (DNAPL) source zones is essential for designing effective remediation strategies, and for assessing the efficacy of treatment. In this study high-resolution cross-hole electrical resistivity tomography (ERT) was evaluated as a means of monitoring a field-scale in-situ bioremediation experiment, in which emulsified vegetable oil (EVO) electron donor was injected into a trichloroethene source zone. Baseline ERT scans delineated the geometry of the interface between the contaminated alluvial aquifer and the underlying mudstone bedrock, and also the extent of drilling-induced physical heterogeneity. Time-lapse ERT images revealed major preferential flow pathways in the source and plume zones, which were corroborated by multiple lines of evidence, including geochemical monitoring and hydraulic testing using high density multilevel sampler arrays within the geophysical imaging planes. These pathways were shown to control the spatial distribution of the injected EVO, and a bicarbonate buffer introduced into the cell for pH control. Resistivity signatures were observed within the preferential flow pathways that were consistent with elevated chloride levels, providing tentative evidence from ERT of the biodegradation of chlorinated solvents.

  17. Immobilization of bacteria isolated from the mining areas on polymeric supports for bioremediation

    International Nuclear Information System (INIS)

    Today pollution is an important environmental problem. Many bacteria have the ability to degrade several types of pollutants in various media (soil, water and air) are used in bioremediation. The present work is to study bacterial diversity colonizing contaminated soil from a mining site in the region of Gafsa and Sfax phosphogypsum and evaluate their potential in bioremediation. Three bacterial strains were selected based on the presence of pigments. These strains have been studied for their tolerances of strontium. Selected strains, was assessed for its bioremediation potential to confirm his use in the biodeppolution processes.

  18. Bioremediation of oil on shoreline environments: development of techniques and guidelines

    International Nuclear Information System (INIS)

    Over the last 20 years, the development of operational procedures to accelerate the natural biodegradation rates of oil spilled on shoreline environments has been the focus of numerous research programs. As a result, bioremediation has been demonstrated to be an effective oil spill countermeasure for use in cobble, sand beach, salt marsh, and mudflat environments. Today, studies are directed towards improving the efficacy and evaluating the ecological impacts of available bioremediation agents and/or procedures. This review describes the latest developments in bioremediation strategies and their key success factors. (author)

  19. Potential of cold-adapted microorganisms for bioremediation of oil-polluted Alpine soils

    International Nuclear Information System (INIS)

    The environmental contamination by organic pollutants is a widespread problem in all climates. The most widely distributed pollution can be attributed to oil contamination. Bioremediation methods can provide efficient, inexpensive and environmentally safe cleanup tools. The role of cold-adapted microorganisms for the bioremediation of experimentally and chronically oil-contaminated Alpine soils was evaluated in the studies described. The results demonstrated that there is a considerable potential for oil bioremediation in Alpine soils. Oil biodegradation can be significantly enhanced by biostimulation (inorganic nutrient supply), but a complete oil elimination is not possible by employing biological decontamination alone. (Author)

  20. Semantic Similarity Calculation of Chinese Word

    Directory of Open Access Journals (Sweden)

    Liqiang Pan

    2014-08-01

    Full Text Available This paper puts forward a two layers computing method to calculate semantic similarity of Chinese word. Firstly, using Latent Dirichlet Allocation (LDA subject model to generate subject spatial domain. Then mapping word into topic space and forming topic distribution which is used to calculate semantic similarity of word(the first layer computing. Finally, using semantic dictionary "HowNet" to deeply excavate semantic similarity of word (the second layer computing. This method not only overcomes the problem that it’s not specific enough merely using LDA to calculate semantic similarity of word, but also solves the problems such as new words (haven’t been added in dictionary and without considering specific context when calculating semantic similarity based on semantic dictionary "HowNet". By experimental comparison, this thesis proves feasibility,availability and advantages of the calculation method.

  1. Bioremediation of Metals and Radionuclides: What It Is and How It Works (2nd Edition)

    Energy Technology Data Exchange (ETDEWEB)

    Palmisano, Anna; Hazen, Terry

    2003-09-30

    This primer is intended for people interested in environmental problems of the U.S. Department of Energy (DOE) and in their potential solutions. It will specifically look at some of the more hazardous metal and radionuclide contaminants found on DOE lands and at the possibilities for using bioremediation technology to clean up these contaminants. The second edition of the primer incorporates recent findings by researchers in DOE's Natural and Accelerated Bioremediation Research (NABIR) Program. Bioremediation is a technology that can be used to reduce, eliminate, or contain hazardous waste. Over the past two decades, it has become widely accepted that microorganisms, and to a lesser extent plants, can transform and degrade many types of contaminants. These transformation and degradation processes vary, depending on the physical-chemical environment, microbial communities, and nature of the contaminant. This technology includes intrinsic bioremediation, which relies on naturally occurring processes, and accelerated bioremediation, which enhances microbial degradation or transformation through the addition of nutrients (biostimulation) or inoculation with microorganisms (bioaugmentation). Over the past few years, interest in bioremediation has increased. It has become clear that many organic contaminants such as hydrocarbon fuels can be degraded to relatively harmless products such as CO{sub 2} (the end result of the degradation process). Waste water managers and scientists have also found that microorganisms can interact with metals and convert them from one chemical form to another. Laboratory tests and ex situ bioremediation applications have shown that microorganisms can change the valence, or oxidation state, of some heavy metals (e.g., chromium and mercury) and radionuclides (e.g., uranium) by using them as electron acceptors. In some cases, the solubility of the altered species decreases and the contaminant is immobilized in situ, i.e., precipitated into

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

    Science.gov (United States)

    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

  3. Evaluation of bio-remediation technologies for PAHs contaminated soils

    International Nuclear Information System (INIS)

    Natural attenuation is a new concept related to polluted soil remediation. Can be understood like an 'in situ' bio-remediation process with low technical intervention. This low intervention may be in order to follow the behaviour of pollutants 'monitored natural attenuation' or include an optimisation process to improve biological remediation. The use of this technology is a fact for light hydrocarbon polluted soil, but few is known about the behaviour of polycyclic aromatic hydrocarbons (PAHs) in this process. PAHs are more recalcitrant to bio-remediation due to their physic-chemical characteristics, mainly hydrophobicity and electrochemical stability. PAHs are a kind of pollutants widely distributed in the environment, not only in the proximity of the source. This linked to the characteristics of some of them related to toxicity and mutagenicity implies its inclusion as target compounds from an environmental point of view. Their low availability, solubility and the strong tendency to bind to soil particle, especially to the organic phase affect PAHs biological mineralisation. So, if the pollutant is not available to microorganisms it can not be bio-degraded. Bioavailability can be assessed form several but complementary points of view: physico-chemical and biological. First including the term availability and the second to point out the capacity of soil microorganisms to mineralize PAHs. Availability and Bio-degradability must be determined, as well as the presence and activity of specific degraders among the soil organisms, once settled these points is necessary to study the biological requirements to optimise biodegradation kinetics of these compounds. In this work we present a study carried out on a soil, contaminated by PAHs, the study includes three main topics: bioavailability assessment (both term availability and bio-degradability), bio-remediation assessment, once optimised conditions for natural attenuation and finally a simulation of the

  4. Augmented In Situ Subsurface Bioremediation Process™BIO-REM, Inc. - Demonstration Bulletin

    Science.gov (United States)

    The Augmented In Situ Subsurface Bioremediation Process™ developed by BIO-REM, Inc., uses microaerophilic bacteria and micronutrients (H-10) and surface tension depressants/penetrants for the treatment of hydrocarbon contaminated soils and groundwater. The bacteria utilize hydroc...

  5. AQUIFER PROTIST RESPONSE AND THE POTENTIAL FOR TCE BIOREMEDIATION WITH BURKHOLDERIA CEPACIA G4 PR1

    Science.gov (United States)

    The introduction of bacteria into the environment for bioremediation purposes (bioaugmentation) requires analysis and monitoring of the persistence and activity of microbial population for efficacy and risk assessment purposes. Burkholderia cepacia G4 PR123 and PR131 constitutive...

  6. Bioremediation of metals and radionuclides: What it is and How itWorks

    Energy Technology Data Exchange (ETDEWEB)

    McCullough, J.; Hazen, Terry; Benson, Sally

    1999-01-01

    This primer is intended for people interested in DOE environmental problems and in their potential solutions. It will specifically look at some of the more hazardous metal and radionuclide contaminants found on DOE lands and at the possibilities for using bioremediation technology to clean up these contaminants. Bioremediation is a technology that can be used to reduce, eliminate, or contain hazardous waste. Over the past two decades, it has become widely accepted that microorganisms, and to a lesser extent plants, can transform and degrade many types of contaminants. These transformation and degradation processes vary, depending on physical environment, microbial communities, and nature of contaminant. This technology includes intrinsic bioremediation, which relies on naturally occurring processes, and accelerated bioremediation, which enhances microbial degradation or transformation through inoculation with microorganisms (bioaugmentation) or the addition of nutrients (biostimulation).

  7. SITE TECHNOLOGY CAPSULE: J.R. SIMPLOT EX-SITU BIOREMEDIATION TECHNOLOGY: DINOSEB

    Science.gov (United States)

    The J.R. Simplot Ex-Situ Bioremediation Technology is designed to anaerobically degrade nitroaromatic and energetic compounds in soils and liquids without forming identifiable toxic intermediate compounds produced by other biotreatment methods. This technology was evaluated un...

  8. SITE TECHNOLOGY CAPSULE: GRACE DEARBORN INC.'S DARAMEND BIOREMEDIATION TECHNOLOGY

    Science.gov (United States)

    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 microorganisms and...

  9. Bioremediation efficacy in Marrow Marsh following the Apex oil spill, Galveston Bay, Texas

    International Nuclear Information System (INIS)

    Samples taken from Marrow Marsh in Galveston Bay, Texas were taken to assess the efficacy of the August 5, 1990 bioremediation treatment in the marsh following the Apex barges oil spill on July 28, 1990. The bioremediation treatment combined a lyophilized bacterial mixture and a nutrient mix containing phosphorus and nitrogen. Samples from the marsh had been collected over a 96 h period from both treated and untreated oiled sites. Oil fingerprinting, fatty acid analysis, polynuclear aromatic hydrocarbons analysis, and total petroleum hydrocarbons analysis were performed to evaluate changes in the chemical characteristics of spilled oil. Results of analyses, although not statistically reliable, failed to support the occurrence of any definite chemical alteration in the spilled oil that could be attributed to the bioremediation treatment. The relatively short sampling period and the number of samples taken, however, may have been insufficient to document the efficacy of the overall bioremediation effect. 13 refs., 6 figs., 4 tabs

  10. Removing environmental organic pollutants with bioremediation and phytoremediation.

    Science.gov (United States)

    Kang, Jun Won

    2014-06-01

    Hazardous organic pollutants represent a threat to human, animal, and environmental health. If left unmanaged, these pollutants could cause concern. Many researchers have stepped up efforts to find more sustainable and cost-effective alternatives to using hazardous chemicals and treatments to remove existing harmful pollutants. Environmental biotechnology, such as bioremediation and phytoremediation, is a promising field that utilizes natural resources including microbes and plants to eliminate toxic organic contaminants. This technology offers an attractive alternative to other conventional remediation processes because of its relatively low cost and environmentally-friendly method. This review discusses current biological technologies for the removal of organic contaminants, including chlorinated hydrocarbons, focusing on their limitation and recent efforts to correct the drawbacks.

  11. Deploying in situ bioremediation at the Hanford Site

    International Nuclear Information System (INIS)

    An innovative in-situ bioremediation technology was developed by Pacific Northwest Laboratory (PNL) to destroy nitrate and carbon tetrachloride (CC14) in the Hanford ground water. The goal of this in-situ treatment process is to stimulate native microorganisms to degrade nitrate and CCl4. Nutrient solutions are distributed in the contaminated aquifer to create a biological treatment zone. This technology is being demonstrated at the US Department of Energy's Hanford Site to provide the design, operating, and cost information needed to assess its effectiveness in contaminated ground water. The process design and field operations for demonstration of this technology are influenced by the physical, chemical, and microbiological properties observed at the site. A description of the technology is presented including the well network design, nutrient injection equipment, and means for controlling the hydraulics and microbial reactions of the treatment process

  12. An evaluation of in-situ bioremediation processes

    International Nuclear Information System (INIS)

    Remediation of petroleum hydrocarbons in groundwater was the primary focus in the initial application of in-situ bioremediation which, from its development in the 1970s, has grown to become one of the most promising technologies for the degradation of a wide variety of organic contaminants. The degradation of contaminants in subsurface soils is the current new focus of the technology. While the need for improvements in the technology does exist, the indisputable fact remains that this technology is by far the least expensive and that it has the capability to provide long term reduced levels of contaminants or long term complete remediation of contaminated sites. The aim of this paper is to disclose pertinent information related to current conditions and current feelings in the area of new research, novel applications, new government regulations, and an overview of new topics on the horizon that relate to the overall technology

  13. Bioremediation of municipal solid waste by windrow composting.

    Science.gov (United States)

    Manjula, G; Ravikannan, S P; Meenambal, T

    2013-10-01

    Due to rapid urbanization and economic development the urban cities are facing the problem of solid waste management. It is one among the major challenges faced by governing bodies. Bioremediation of municipal solid waste can be effectively done by windrow composting. In this study, a consortium of effective microorganisms was used for the windrow composting process. About 500 kg of shredded waste was placed in two windrows and 1 litre effective microorganisms were sprayed on one of the windrows. The variation in physical and chemical parameters was monitored throughout the process. The results indicate that usage of effective microorganisms not only shortens the stabilization time but also improves product quality. The final product was more stable and homogenous and can be effectively used as soil conditioner. PMID:25906592

  14. Intrinsic bioremediation potential of a chronically polluted marine coastal area.

    Science.gov (United States)

    Catania, Valentina; Santisi, Santina; Signa, Geraldina; Vizzini, Salvatrice; Mazzola, Antonio; Cappello, Simone; Yakimov, Michail M; Quatrini, Paola

    2015-10-15

    A microbiological survey of the Priolo Bay (eastern coast of Sicily, Ionian Sea), a chronically polluted marine coastal area, was carried out in order to discern its intrinsic bioremediation potential. Microbiological analysis, 16S rDNA-based DGGE fingerprinting and PLFAs analysis were performed on seawater and sediment samples from six stations on two transects. Higher diversity and variability among stations was detected by DGGE in sediment than in water samples although seawater revealed higher diversity of culturable hydrocarbon-degrading bacteria. The most polluted sediment hosted higher total bacterial diversity and higher abundance and diversity of culturable HC degraders. Alkane- and PAH-degrading bacteria were isolated from all stations and assigned to Alcanivorax, Marinobacter, Thalassospira, Alteromonas and Oleibacter (first isolation from the Mediterranean area). High total microbial diversity associated to a large selection of HC degraders is believed to contribute to natural attenuation of the area, provided that new contaminant contributions are avoided.

  15. UTILIZING Aspergillus niger FOR BIOREMEDIATION OF TANNERY EFFLUENT

    Directory of Open Access Journals (Sweden)

    Jyoti Bisht

    2014-03-01

    Full Text Available Tannery waste water is characterized by highly toxic ammonium, sulfates, surfactants, acids, dyes, sulfonated oils and organic substances, including natural or synthetic tannins. This study was designed to study the potential of Aspergillus niger for bioremediation of tannery effluent. Addition of glucose as a carbon source in the tannery effluent encouraged the growth of A. niger but there was no change in physico-chemical parameters. The toxic effects were mostly reduced after treatment when 20% mineral salt medium was added in tannery effluent. Colour, COD, TS, TDS, TSS, chlorides, sulfides and chromium reduction were 71.9%, 72.1%, 69.0%, 65.0%, 68.1%, 66.8%, 65.7% and 57.8%, respectively.

  16. Engineering microbial consortia to enhance biomining and bioremediation

    Directory of Open Access Journals (Sweden)

    Karl Dietrich Brune

    2012-06-01

    Full Text Available In natural environments microorganisms commonly exist as communities of multiple species that are capable of performing more varied and complicated tasks than clonal populations. Synthetic biologists have engineered clonal populations with characteristics such as differentiation, memory and pattern formation, which are usually associated with more complex multicellular organisms. The prospect of designing microbial communities has alluring possibilities for environmental, biomedical and energy applications and is likely to reveal insight into how natural microbial consortia function. Cell signaling and communication pathways between different species are likely to be key processes for designing novel functions in synthetic and natural consortia. Recent efforts to engineer synthetic microbial interactions will be reviewed here, with particular emphasis given to research with significance for industrial applications in the field of biomining and bioremediation of acid mine drainage.

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

    Science.gov (United States)

    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.

  18. Bioremediation of organic pollutants in a radioactive wastewater

    International Nuclear Information System (INIS)

    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)

  19. Intrinsic bioremediation potential of a chronically polluted marine coastal area.

    Science.gov (United States)

    Catania, Valentina; Santisi, Santina; Signa, Geraldina; Vizzini, Salvatrice; Mazzola, Antonio; Cappello, Simone; Yakimov, Michail M; Quatrini, Paola

    2015-10-15

    A microbiological survey of the Priolo Bay (eastern coast of Sicily, Ionian Sea), a chronically polluted marine coastal area, was carried out in order to discern its intrinsic bioremediation potential. Microbiological analysis, 16S rDNA-based DGGE fingerprinting and PLFAs analysis were performed on seawater and sediment samples from six stations on two transects. Higher diversity and variability among stations was detected by DGGE in sediment than in water samples although seawater revealed higher diversity of culturable hydrocarbon-degrading bacteria. The most polluted sediment hosted higher total bacterial diversity and higher abundance and diversity of culturable HC degraders. Alkane- and PAH-degrading bacteria were isolated from all stations and assigned to Alcanivorax, Marinobacter, Thalassospira, Alteromonas and Oleibacter (first isolation from the Mediterranean area). High total microbial diversity associated to a large selection of HC degraders is believed to contribute to natural attenuation of the area, provided that new contaminant contributions are avoided. PMID:26248825

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

    Science.gov (United States)

    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

  1. Microbial population changes during bioremediation of an experimental oil spill

    International Nuclear Information System (INIS)

    Three crude oil bioremediation techniques were tested in a field experiment in Delaware, United States to determine the progress of natural and accelerated attenuation during a controlled oil spill. The four treatments studied were: no oil control, oil alone, oil plus nutrients, and oil plus nutrients plus an indigenous inoculum. During the first 14 weeks, microbial numbers were high but were steadily declining with no major differences among treatments. However, after the 14 week period, phospholipid fatty acid (PLFA) results showed that the communities shifted from being composed mostly of eukaryotes to gram-negative bacteria. The dominant species diversity changed and increased significantly over 14 weeks. Nutrient addition and the addition of the indigenous inoculum altered the nature of this change. Gas chromatography/mass spectrometry analyses of the oil analytes detected major differences in rates of biodegradation between the amended and unamended natural attenuation plots, but not between the nutrient and inoculum plots. 11 refs., 3 figs

  2. San Jacinto River oil spill: wetland bioremediation project

    International Nuclear Information System (INIS)

    Gasoline, diesel and unrefined Arabian light crude oil were accidentally released into the San Jacinto River after a series of pipelines ruptured. Natural removal processes (volatilization, dissolution, weathering), fire, and the spill clean-up effort, removed approximately 95% of the petroleum. The area where residual oil was found was an estuarine wetland on the lower San Jacinto River. Samples were collected from 21 study areas and an evaluation of the varying levels of bioremediation was conducted. Phase one has been completed and involved the evaluation of the natural recovery of oil from the spill. Phase two was still in progress and involved the addition of inorganic nutrients and the alternate electron acceptor to enhance the biodegradation of the petroleum. Results showed that biodegradation was responsible for much of the reduction of certain components in petroleum within the first 150 days. 12 refs., 8 figs

  3. Enhanced bioremediation of oil spills in the sea.

    Science.gov (United States)

    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

  4. An evaluation of in-situ bioremediation processes

    Energy Technology Data Exchange (ETDEWEB)

    Cole, L.L. [Prairie View A and M Univ., TX (United States); Rashidi, M. [Lawrence Livermore National Lab., CA (United States). Environmental Programs Directorate

    1996-08-01

    Remediation of petroleum hydrocarbons in groundwater was the primary focus in the initial application of in-situ bioremediation which, from its development in the 1970s, has grown to become one of the most promising technologies for the degradation of a wide variety of organic contaminants. The degradation of contaminants in subsurface soils is the current new focus of the technology. While the need for improvements in the technology does exist, the indisputable fact remains that this technology is by far the least expensive and that it has the capability to provide long term reduced levels of contaminants or long term complete remediation of contaminated sites. The aim of this paper is to disclose pertinent information related to current conditions and current feelings in the area of new research, novel applications, new government regulations, and an overview of new topics on the horizon that relate to the overall technology.

  5. Petroleum-Degrading Enzymes: Bioremediation and New Prospects

    Directory of Open Access Journals (Sweden)

    R. S. Peixoto

    2011-01-01

    Full Text Available Anthropogenic forces, such as petroleum spills and the incomplete combustion of fossil fuels, have caused an accumulation of petroleum hydrocarbons in the environment. The accumulation of petroleum and its derivatives now constitutes an important environmental problem. Biocatalysis introduces new ways to improve the development of bioremediation strategies. The recent application of molecular tools to biocatalysis may improve bioprospecting research, enzyme yield recovery, and enzyme specificity, thus increasing cost-benefit ratios. Enzymatic remediation is a valuable alternative as it can be easier to work with than whole organisms, especially in extreme environments. Furthermore, the use of free enzymes avoids the release of exotic or genetically modified organisms (GMO in the environment.

  6. SPATIAL STABILITY

    OpenAIRE

    Pascal Mossay

    2004-01-01

    We consider a continuous spatial economy consisting of pure exchange local economies. Agents are allowed to change their location over time as a response to spatial utility differentials. These spatial adjustments toward higher utility neighborhoods lead the spatial economy to converge to a spatially uniform allocation of resources, provided that the matrix of price effects is quasi-negative definite. Furthermore our model provides a real time interpretation of the tâtonnement story. Also, sp...

  7. Insight in the PCB-degrading functional community in long-term contaminated soil under bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Petric, Ines; Hrsak, Dubravka; Udikovic-Kolic, Nikolina [Ruder Boskovic Inst., Division for Marine and Environmental Research, Zagreb (Croatia); Fingler, Sanja [Inst. for Medical Research and Occupational Health, Zagreb (Croatia); Bru, David; Martin-Laurent, Fabrice [INRA, Univ. der Bourgogne, Soil and Environmental Microbiology, Dijon (France)

    2011-02-15

    A small-scale bioremediation assay was developed in order to get insight into the functioning of a polychlorinated biphenyl (PCB) degrading community during the time course of bioremediation treatment of a contaminated soil. The study was conducted with the aim to better understand the key mechanisms involved in PCB-removal from soils. Materials and methods Two bioremediation strategies were applied in the assay: (a) biostimulation (addition of carvone as inducer of biphenyl pathway, soya lecithin for improving PCB bioavailability, and xylose as supplemental carbon source) and (b) bioaugmentation with selected seed cultures TSZ7 or Rhodococcus sp. Z6 originating from the transformer station soil and showing substantial PCB-degrading activity. Functional PCB-degrading community was investigated by using molecular-based approaches (sequencing, qPCR) targeting bphA and bphC genes, coding key enzymes of the upper biphenyl pathway, in soil DNA extracts. In addition, kinetics of PCBs removal during the bioremediation treatment was determined using gas chromatography mass spectrometry analyses. Results and discussion bphA-based phylogeny revealed that bioremediation affected the structure of the PCB-degrading community in soils, with Rhodococcus-like bacterial populations developing as dominant members. Tracking of this population further indicated that applied bioremediation treatments led to its enrichment within the PCB-degrading community. The abundance of the PCB-degrading community, estimated by quantifying the copy number of bphA and bphC genes, revealed that it represented up to 0.3% of the total bacterial community. All bioremediation treatments were shown to enhance PCB reduction in soils, with approximately 40% of total PCBs being removed during a 1-year period. The faster PCB reduction achieved in bioaugmented soils suggested an important role of the seed cultures in bioremediation processes. Conclusions The PCBs degrading community was modified in response to

  8. Bioremediation of industrially contaminated soil using compost and plant technology.

    Science.gov (United States)

    Taiwo, A M; Gbadebo, A M; Oyedepo, J A; Ojekunle, Z O; Alo, O M; Oyeniran, A A; Onalaja, O J; Ogunjimi, D; Taiwo, O T

    2016-03-01

    Compost technology can be utilized for bioremediation of contaminated soil using the active microorganisms present in the matrix of contaminants. This study examined bioremediation of industrially polluted soil using the compost and plant technology. Soil samples were collected at the vicinity of three industrial locations in Ogun State and a goldmine site in Iperindo, Osun State in March, 2014. The compost used was made from cow dung, water hyacinth and sawdust for a period of twelve weeks. The matured compost was mixed with contaminated soil samples in a five-ratio pot experimental design. The compost and contaminated soil samples were analyzed using the standard procedures for pH, electrical conductivity (EC), organic carbon (OC), total nitrogen (TN), phosphorus, exchangeable cations (Na, K, Ca and Mg) and heavy metals (Fe, Mn, Cu, Zn and Cr). Kenaf (Hibiscus cannabinus) seeds were also planted for co-remediation of metals. The growth parameters of Kenaf plants were observed weekly for a period of one month. Results showed that during the one-month remediation experiment, treatments with 'compost-only' removed 49 ± 8% Mn, 32 ± 7% Fe, 29 ± 11% Zn, 27 ± 6% Cu and 11 ± 5% Cr from the contaminated soil. On the other hand, treatments with 'compost+plant' remediated 71 ± 8% Mn, 63 ± 3% Fe, 59 ± 11% Zn, 40 ± 6% Cu and 5 ± 4% Cr. Enrichment factor (EF) of metals in the compost was low while that of Cu (EF=7.3) and Zn (EF=8.6) were high in the contaminated soils. Bioaccumulation factor (BF) revealed low metal uptake by Kenaf plant. The growth parameters of Kenaf plant showed steady increments from week 1 to week 4 of planting.

  9. Fungal treatment: a prospective process for eco-friendly bioremediation of wastewater sludge

    International Nuclear Information System (INIS)

    None of the conventional techniques is safe and environmental friendly for wastewaters/sludge disposal. A sustainable, safe and environmental friendly biological technique is a great apprehension to the relevant scientists. Since the fungal treatment was exercised to evaluate its potentially for sustainable bioseparation and bioremediation of wastewater. Bioseparation and bioremediation of wastewater sludge by fungal inoculation implied the decreasing of bio solids, total suspended solids (TSS), turbidity, chemical oxygen demand (COD) and specific resistance to filtration (SRF) of wastewater. (Author)

  10. Role of Microbial Enzymes in the Bioremediation of Pollutants: A Review

    OpenAIRE

    Karigar, Chandrakant S.; Rao, Shwetha S.

    2011-01-01

    A large number of enzymes from bacteria, fungi, and plants have been reported to be involved in the biodegradation of toxic organic pollutants. Bioremediation is a cost effective and nature friendly biotechnology that is powered by microbial enzymes. The research activity in this area would contribute towards developing advanced bioprocess technology to reduce the toxicity of the pollutants and also to obtain novel useful substances. The information on the mechanisms of bioremediation-related...

  11. Bioremediation: Hope/Hype for Environmental Cleanup (LBNL Summer Lecture Series)

    Energy Technology Data Exchange (ETDEWEB)

    Hazen, Terry [LBNL, Ecology Dept

    2007-07-18

    Summer Lecture Series 2007: Terry Hazen, Senior Staff Scientists and Head of the LBNL Ecology Department, discusses when it's best to resort to engineered bioremediation of contaminated sites, and when it's best to rely on natural attenuation. Recent advances have greatly broadened the potential applications for bioremediation. At the same time, scientists' knowledge of biogeochemical processes has advanced and they can better gauge how quickly and completely contaminants can be degraded without human intervention.

  12. Metagenomic Analysis of the Bioremediation of Diesel-Contaminated Canadian High Arctic Soils

    OpenAIRE

    Yergeau, Etienne; Sanschagrin, Sylvie; Beaumier, Danielle; Greer, Charles W.

    2012-01-01

    As human activity in the Arctic increases, so does the risk of hydrocarbon pollution events. On site bioremediation of contaminated soil is the only feasible clean up solution in these remote areas, but degradation rates vary widely between bioremediation treatments. Most previous studies have focused on the feasibility of on site clean-up and very little attention has been given to the microbial and functional communities involved and their ecology. Here, we ask the question: which microorga...

  13. Correlation between social proximity and mobility similarity

    CERN Document Server

    Fan, Chao; Huang, Junming; Rong, Zhihai; Zhou, Tao

    2016-01-01

    Human behaviors exhibit ubiquitous correlations in many aspects, such as individual and collective levels, temporal and spatial dimensions, content, social and geographical layers. With rich Internet data of online behaviors becoming available, it attracts academic interests to explore human mobility similarity from the perspective of social network proximity. Existent analysis shows a strong correlation between online social proximity and offline mobility similari- ty, namely, mobile records between friends are significantly more similar than between strangers, and those between friends with common neighbors are even more similar. We argue the importance of the number and diversity of com- mon friends, with a counter intuitive finding that the number of common friends has no positive impact on mobility similarity while the diversity plays a key role, disagreeing with previous studies. Our analysis provides a novel view for better understanding the coupling between human online and offline behaviors, and will...

  14. Ecotoxicity monitoring and bioindicator screening of oil-contaminated soil during bioremediation.

    Science.gov (United States)

    Shen, Weihang; Zhu, Nengwu; Cui, Jiaying; Wang, Huajin; Dang, Zhi; Wu, Pingxiao; Luo, Yidan; Shi, Chaohong

    2016-02-01

    A series of toxicity bioassays was conducted to monitor the ecotoxicity of soils in the different phases of bioremediation. Artificially oil-contaminated soil was inoculated with a petroleum hydrocarbon-degrading bacterial consortium containing Burkholderia cepacia GS3C, Sphingomonas GY2B and Pandoraea pnomenusa GP3B strains adapted to crude oil. Soil ecotoxicity in different phases of bioremediation was examined by monitoring total petroleum hydrocarbons, soil enzyme activities, phytotoxicity (inhibition of seed germination and plant growth), malonaldehyde content, superoxide dismutase activity and bacterial luminescence. Although the total petroleum hydrocarbon (TPH) concentration in soil was reduced by 64.4%, forty days after bioremediation, the phytotoxicity and Photobacterium phosphoreum ecotoxicity test results indicated an initial increase in ecotoxicity, suggesting the formation of intermediate metabolites characterized by high toxicity and low bioavailability during bioremediation. The ecotoxicity values are a more valid indicator for evaluating the effectiveness of bioremediation techniques compared with only using the total petroleum hydrocarbon concentrations. Among all of the potential indicators that could be used to evaluate the effectiveness of bioremediation techniques, soil enzyme activities, phytotoxicity (inhibition of plant height, shoot weight and root fresh weight), malonaldehyde content, superoxide dismutase activity and luminescence of P. phosphoreum were the most sensitive. PMID:26491984

  15. Ecotoxicity monitoring and bioindicator screening of oil-contaminated soil during bioremediation.

    Science.gov (United States)

    Shen, Weihang; Zhu, Nengwu; Cui, Jiaying; Wang, Huajin; Dang, Zhi; Wu, Pingxiao; Luo, Yidan; Shi, Chaohong

    2016-02-01

    A series of toxicity bioassays was conducted to monitor the ecotoxicity of soils in the different phases of bioremediation. Artificially oil-contaminated soil was inoculated with a petroleum hydrocarbon-degrading bacterial consortium containing Burkholderia cepacia GS3C, Sphingomonas GY2B and Pandoraea pnomenusa GP3B strains adapted to crude oil. Soil ecotoxicity in different phases of bioremediation was examined by monitoring total petroleum hydrocarbons, soil enzyme activities, phytotoxicity (inhibition of seed germination and plant growth), malonaldehyde content, superoxide dismutase activity and bacterial luminescence. Although the total petroleum hydrocarbon (TPH) concentration in soil was reduced by 64.4%, forty days after bioremediation, the phytotoxicity and Photobacterium phosphoreum ecotoxicity test results indicated an initial increase in ecotoxicity, suggesting the formation of intermediate metabolites characterized by high toxicity and low bioavailability during bioremediation. The ecotoxicity values are a more valid indicator for evaluating the effectiveness of bioremediation techniques compared with only using the total petroleum hydrocarbon concentrations. Among all of the potential indicators that could be used to evaluate the effectiveness of bioremediation techniques, soil enzyme activities, phytotoxicity (inhibition of plant height, shoot weight and root fresh weight), malonaldehyde content, superoxide dismutase activity and luminescence of P. phosphoreum were the most sensitive.

  16. Effects on lead bioavailability and plant uptake during the bioremediation of soil PAHs

    Energy Technology Data Exchange (ETDEWEB)

    Amezcua-Allieri, M.A. [Inst. Politecnico Nacional, Mexico City (Mexico); Rodriguez-Vazquez, R. [CINVESTAV, Mexico City (Mexico)

    2008-07-01

    Polycyclic aromatic hydrocarbons (PAHs) are a group of priority pollutants that are present in the soils of many industrially contaminated sites. In Mexico, the petrochemical industry is the main source of soil pollution. Soils polluted with PAHs are often accompanied by high levels of metals. Although bioremediation of soil contaminated with PAHs have received increasing attentions, the influence of microbial activity on metal behaviour is not understood. For that reason, this study investigated lead behaviour during the bioremoval of phenanthrene in soils sampled from Tabasco, Mexico. Lead bioavailable concentrations were evaluated by diffusive gradients in thin-films (DGT). Metal uptake to plants was quantified. Lead concentrations were determined before and after organic removal by Penicillium frequentans and soil microflora. Metal uptake by Echinochloa polystachya and Triticum aestivum L was also investigated. DGT concentrations increased significantly after the addition of fungi in the presence of plants before bioremediation and after fungal addition. Although DGT responded immediately to uptake, plant uptake did not begin immediately. The fungal bioremediation reduced organic contaminants significantly while it increased bioavailable metal concentrations and plant uptake. The results highlight the impact of bioremediation of organic contaminants on trace metal behaviour. The bioremediation process makes the toxic lead more available to plants, and therefore more metal may be incorporated into the human food chain if crops grown on bioremediated soil are used for human or animal consumption. 15 refs., 3 figs.

  17. Polishing of Anaerobic Secondary Effluent and Symbiotic Bioremediation of Raw Municipal Wastewater by Chlorella Vulgaris

    KAUST Repository

    Cheng, Tuoyuan

    2016-05-01

    To assess polishing of anaerobic secondary effluent and symbiotic bioremediation of primary effluent by microalgae, bench scale bubbling column reactors were operated in batch modes to test nutrients removal capacity and associated factors. Chemical oxygen demand (COD) together with oil and grease in terms of hexane extractable material (HEM) in the reactors were measured after batch cultivation tests of Chlorella Vulgaris, indicating the releasing algal metabolites were oleaginous (dissolved HEM up to 8.470 mg/L) and might hazard effluent quality. Ultrafiltration adopted as solid-liquid separation step was studied via critical flux and liquid chromatography-organic carbon detection (LC-OCD) analysis. Although nutrients removal was dominated by algal assimilation, nitrogen removal (99.6% maximum) was affected by generation time (2.49 days minimum) instead of specific nitrogen removal rate (sN, 20.72% maximum), while phosphorus removal (49.83% maximum) was related to both generation time and specific phosphorus removal rate (sP, 1.50% maximum). COD increase was affected by cell concentration (370.90 mg/L maximum), specific COD change rate (sCOD, 0.87 maximum) and shading effect. sCOD results implied algal metabolic pathway shift under nutrients stress, generally from lipid accumulation to starch accumulation when phosphorus lower than 5 mg/L, while HEM for batches with initial nitrogen of 10 mg/L implied this threshold around 8 mg/L. HEM and COD results implied algal metabolic pathway shift under nutrients stress. Anaerobic membrane bioreactor effluent polishing showed similar results to synthetic anaerobic secondary effluent with slight inhibition while 4 symbiotic bioremediation of raw municipal wastewater with microalgae and activated sludge showed competition for ammonium together with precipitation or microalgal luxury uptake of phosphorus. Critical flux was governed by algal cell concentration for ultrafiltration membrane with pore size of 30 nm, while

  18. Isolation, identification and characterization of indigenous fungi for bioremediation of hexavalent chromium, nickel and cobalt

    Science.gov (United States)

    Hernahadini, Nelis; Suhandono, Sony; Choesin, Devi N.; Chaerun, Siti K.; Kadarusman, Ade

    2014-03-01

    Waste from nickel mining of Sorowako in South Sulawesi contains hexavalent chromium, nickel and cobalt metals in high concentration and may have a negative impact to the environment. Common waste treatment systems such as chemical treatment using a reducing reagent may still have a negative impact. Bioremediation using fungi or bacteria becomes more popular because it is an environmentally friendly alternative. The purposes of this study are to isolate and identify indigenous fungi that are resistant to heavy metals (hexavalent chromium, nickel, and cobalt) and are capable of reducing the concentration of metals in mining wastes. Ten fungal isolates were successfully isolated from the soils and pond sediments in the area of nickel mining in Sorowako. Selection of superior isolate was carried out by growing all the isolates on PDA medium, which contained all of the three metals. One superior isolate was identified to be able to grow on medium with concentrations of 6400 ppm hexavalent chromium, 200 ppm nickel and 50 ppm cobalt. Molecular identification and phylogenetic studies of the isolate using fungal PCR primers developed to amplify the ITS (internal transcribed spacer) region showed that the isolate sequence was very close to Trichoderma atroviride with 99.8% similarity. Optimum incubation time for the uptake of hexavalent chromium was 3 days, nickel and cobalt was 5 days, respectively, with an optimum pH of 4.

  19. Algae as an electron donor promoting sulfate reduction for the bioremediation of acid rock drainage.

    Science.gov (United States)

    Ayala-Parra, Pedro; Sierra-Alvarez, Reyes; Field, Jim A

    2016-11-01

    This study assessed bioremediation of acid rock drainage in simulated permeable reactive barriers (PRB) using algae, Chlorella sorokiniana, as the sole electron donor for sulfate-reducing bacteria. Lipid extracted algae (LEA), the residues of biodiesel production, were compared with whole cell algae (WCA) as an electron donor to promote sulfate-reducing activity. Inoculated columns containing anaerobic granular sludge were fed a synthetic medium containing H2SO4 and Cu(2+). Sulfate, sulfide, Cu(2+) and pH were monitored throughout the experiment of 123d. Cu recovered in the column packing at the end of the experiment was evaluated using sequential extraction. Both WCA and LEA promoted 80% of sulfate removal (12.7mg SO4(2-) d(-1)) enabling near complete Cu removal (>99.5%) and alkalinity generation raising the effluent pH to 6.5. No noteworthy sulfate reduction, alkalinity formation and Cu(2+) removal were observed in the endogenous control. In algae amended-columns, Cu(2+) was precipitated with biogenic H2S produced by sulfate reduction. Formation of CuS was evidenced by sequential extraction and X-ray diffraction. LEA and WCA provided similar levels of electron donor based on the COD balance. The results demonstrate an innovative passive remediation system using residual algae biomass from the biodiesel industry. PMID:27318730

  20. Estimating similarity of XML Schemas using path similarity measure

    Directory of Open Access Journals (Sweden)

    Veena Trivedi

    2012-07-01

    Full Text Available In this paper, an attempt has been made to develop an algorithm which estimates the similarity for XML Schemas using multiple similarity measures. For performing the task, the XML Schema element information has been represented in the form of string and four different similarity measure approaches have been employed. To further improve the similarity measure, an overall similarity measure has also been calculated. The approach used in this paper is a distinguished one, as it calculates the similarity between two XML schemas using four approaches and gives an integrated values for the similarity measure. Keywords-componen

  1. Bioremediation of Metals and Radionuclides: What It Is and How It Works (2nd Edition)

    Energy Technology Data Exchange (ETDEWEB)

    Palmisano, Anna; Hazen, Terry

    2003-09-30

    This primer is intended for people interested in environmental problems of the U.S. Department of Energy (DOE) and in their potential solutions. It will specifically look at some of the more hazardous metal and radionuclide contaminants found on DOE lands and at the possibilities for using bioremediation technology to clean up these contaminants. The second edition of the primer incorporates recent findings by researchers in DOE's Natural and Accelerated Bioremediation Research (NABIR) Program. Bioremediation is a technology that can be used to reduce, eliminate, or contain hazardous waste. Over the past two decades, it has become widely accepted that microorganisms, and to a lesser extent plants, can transform and degrade many types of contaminants. These transformation and degradation processes vary, depending on the physical-chemical environment, microbial communities, and nature of the contaminant. This technology includes intrinsic bioremediation, which relies on naturally occurring processes, and accelerated bioremediation, which enhances microbial degradation or transformation through the addition of nutrients (biostimulation) or inoculation with microorganisms (bioaugmentation). Over the past few years, interest in bioremediation has increased. It has become clear that many organic contaminants such as hydrocarbon fuels can be degraded to relatively harmless products such as CO{sub 2} (the end result of the degradation process). Waste water managers and scientists have also found that microorganisms can interact with metals and convert them from one chemical form to another. Laboratory tests and ex situ bioremediation applications have shown that microorganisms can change the valence, or oxidation state, of some heavy metals (e.g., chromium and mercury) and radionuclides (e.g., uranium) by using them as electron acceptors. In some cases, the solubility of the altered species decreases and the contaminant is immobilized in situ, i.e., precipitated into

  2. Assessment of microbial community changes and limiting factors during bioremediation of hydrocarbon-polluted soil with new miniaturized physiological methods

    OpenAIRE

    Kaufmann, Karin

    2004-01-01

    Due to human activities, organic pollutants are spilled to the environment where they threaten public health, often as contaminants of soil or groundwater. Living organisms are able to transform or mineralize many organic pollutants, and bioremediation techniques have been developed to remove pollutants from a contaminated site. However, fast and easy methods to document both the efficacy of bioremediation and the changes in soil microbial communities during bioremediation are not well develo...

  3. Assessment of microbial community changes and limiting factors during bioremediation of hydrocarbon-polluted soil with new miniaturized physiological methods

    OpenAIRE

    Kaufmann, Karin; Holliger, Hans Christof

    2005-01-01

    Due to human activities, organic pollutants are spilled to the environment where they threaten public health, often as contaminants of soil or groundwater. Living organisms are able to transform or mineralize many organic pollutants, and bioremediation techniques have been developed to remove pollutants from a contaminated site. However, fast and easy methods to document both the efficacy of bioremediation and the changes in soil microbial communities during bioremediation are not well develo...

  4. Spatial Sense.

    Science.gov (United States)

    Del Grande, John

    1990-01-01

    Describes seven spatial abilities related to mathematics including eye-motor coordination, figure-ground perception, perceptual constancy, position-in-space perception, perception of spatial relationships, visual discrimination, and visual memory. Discusses the relationship of the spatial abilities to the study of geometry. Lists 19 references.…

  5. Multivariate Time Series Similarity Searching

    OpenAIRE

    Jimin Wang; Yuelong Zhu; Shijin Li; Dingsheng Wan; Pengcheng Zhang

    2014-01-01

    Multivariate time series (MTS) datasets are very common in various financial, multimedia, and hydrological fields. In this paper, a dimension-combination method is proposed to search similar sequences for MTS. Firstly, the similarity of single-dimension series is calculated; then the overall similarity of the MTS is obtained by synthesizing each of the single-dimension similarity based on weighted BORDA voting method. The dimension-combination method could use the existing similarity searchin...

  6. SEAL: Spatio-Textual Similarity Search

    CERN Document Server

    Fan, Ju; Zhou, Lizhu; Chen, Shanshan; Hu, Jun

    2012-01-01

    Location-based services (LBS) have become more and more ubiquitous recently. Existing methods focus on finding relevant points-of-interest (POIs) based on users' locations and query keywords. Nowadays, modern LBS applications generate a new kind of spatio-textual data, regions-of-interest (ROIs), containing region-based spatial information and textual description, e.g., mobile user profiles with active regions and interest tags. To satisfy search requirements on ROIs, we study a new research problem, called spatio-textual similarity search: Given a set of ROIs and a query ROI, we find the similar ROIs by considering spatial overlap and textual similarity. Spatio-textual similarity search has many important applications, e.g., social marketing in location-aware social networks. It calls for an efficient search method to support large scales of spatio-textual data in LBS systems. To this end, we introduce a filter-and-verification framework to compute the answers. In the filter step, we generate signatures for ...

  7. In Situ Bioremediation of Chlorinated Ethenes in Hydraulically-Tight Sediments: Challenges and Limitations

    Science.gov (United States)

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

    2011-12-01

    Chlorinated ethenes, like perchloroethene (PCE) and trichloroethene (TCE), have been widely used by many industries, especially in developed countries like Japan. Because of their wide applications, lack of proper regulation, poor handing, storage and disposal practices in the past, chlorinated ethenes have become a type of the most prevalent contaminants for soils and groundwater pollution. For the sake of their degradability, bioremediation has been considered as a potentially cost-effective and environmentally friendly approach for cleanup of chlorinated ethenes in situ. In this presentation, we briefly overview the status of soil and groundwater pollution, the recent amendment of the Soil Contamination Countermeasures Act in Japan, comparison between the bioremediation and other techniques like pump and treat, and the mechanisms of reductive dechlorination, direct oxidation and co-metabolism of chlorinated ethenes. We then introduce and discuss some recent challenges and advancements in in-situ bioremediation including technologies for accelerating bio-degradation of chlorinated ethenes, technologies for assessing diffusive properties of dissolved hydrogen in hydraulically-tight soil samples, and combination of bioremediation with other techniques like electro-kinetic approach. Limiting factors that may cause incomplete remediation and/or ineffectiveness of bioremediation are examined from biochemical, geochemical and hydro-geological aspects. This study reconfirmed and illustrated that: 1) The key factor for an effective bioremediation is how to disperse a proper accelerating agent throughout the polluted strata, 2) The effective diffusion coefficient of dissolved hydrogen in geologic media is relatively big and is almost independent on their permeability, and 3) To effectively design and perform an accelerated bioremediation, a combination of natural migration with pressurized injection and/or other approaches, like electro-migration, for stimulating mass

  8. INFLUENCE OF TIDE AND WAVES ON WASHOUT OF DISSOLVED NUTRIENTS FROM THE BIOREMEDIATION ZONE OF A COARSE-SAND BEACH: APPLICATION IN OIL-SPILL BIOREMEDIATION

    Science.gov (United States)

    Successful bioremediation of oil-contaminated beaches requires maintenance of a sufficient quantity of growth-limiting nutrients in contact with the oiled beach materials. A conservative tracer study was conducted on a moderate-energy, sandy beach on Delaware Bay to estimate the...

  9. Methodology for bioremediation monitoring of oil wastes contaminated soils by using vegetal bio indicators; Metodologia para monitoramento de biorremediacao de solos contaminados com residuos oleosos com bioindicadores vegetais

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento Neto, Durval; Carvalho, Francisco Jose Pereira de Campos [Parana Univ., Curitiba, PR (Brazil). Curso de Pos-Graduacao em Ciencia do Solo]. E-mail: fjcampos@cce.ufpr.br

    1998-07-01

    This work studies the development of a methodology for the evaluation of the bioremediation status of oil waste contaminated soils, by using vegetal bioindicators for the bioremediation process monitoring, and evaluation of the environmental impacts on the contaminated areas.

  10. Eliciting Public Attitudes Regarding Bioremediation Cleanup Technologies: Lessons Learned from a Consensus Workshop in Idaho

    International Nuclear Information System (INIS)

    During the summer of 2002, we developed and implemented a ''consensus workshop'' with Idaho citizens to elicit their concerns and issues regarding the use of bioremediation as a cleanup technology for radioactive nuclides and heavy metals at Department of Energy (DOE) sites. The consensus workshop is a derivation of a technology assessment method designed to ensure dialogue between experts and lay people. It has its origins in the United States in the form of ''consensus development conferences'' used by the National Institutes of Health (NIH) to elicit professional knowledge and concerns about new medical treatments. Over the last 25 years, NIH has conducted over 100 consensus development conferences. (Jorgensen 1995). The consensus conference is grounded in the idea that technology assessment and policy needs to be socially negotiated among many different stakeholders and groups rather than narrowly defined by a group of experts. To successfully implement new technology, the public requires access to information that addresses a full complement of issues including understanding the organization proposing the technology. The consensus conference method creates an informed dialogue, making technology understandable to the general public and sets it within perspectives and priorities that may differ radically from those of the expert community. While specific outcomes differ depending on the overall context of a conference, one expected outcome is that citizen panel members develop greater knowledge of the technology during the conference process and, sometimes, the entire panel experiences a change in attitude toward the technology and/or the organization proposing its use (Kluver 1995). The purpose of this research project was to explore the efficacy of the consensus conference model as a way to elicit the input of the general public about bioremediation of radionuclides and heavy metals at Department of Energy sites. Objectives of the research included: (1

  11. Bioremediation via in situ microbial degradation of organic pollutants.

    Science.gov (United States)

    Vogt, Carsten; Richnow, Hans Hermann

    2014-01-01

    Contamination of soil and natural waters by organic pollutants is a global problem. The major organic pollutants of point sources are mineral oil, fuel components, and chlorinated hydrocarbons. Research from the last two decades discovered that most of these compounds are biodegradable under anoxic conditions. This has led to the rise of bioremediation strategies based on the in situ biodegradation of pollutants. Monitored natural attenuation is a concept by which a contaminated site is remediated by natural biodegradation; to evaluate such processes, a combination of chemical and microbiological methods are usually used. Compound specific stable isotope analysis emerged as a key method for detecting and quantifying in situ biodegradation. Natural attenuation processes can be initiated or accelerated by manipulating the environmental conditions to become favorable for indigenous pollutant degrading microbial communities or by adding externally breeded specific pollutant degrading microorganisms; these techniques are referred to as enhanced natural attenuation. Xenobiotic micropollutants, such as pesticides or pharmaceuticals, contaminate diffusively large areas in low concentrations; the biodegradation pattern of such contaminations are not yet understood. PMID:24337042

  12. Enzymatic bioremediation of cashew nut shell liquid contamination.

    Science.gov (United States)

    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

  13. Fungal degradation of pesticides - construction of microbial consortia for bioremediation

    DEFF Research Database (Denmark)

    Ellegaard-Jensen, Lea

    and Mortierella sp. LEJ703. In the experimental setup a layer of sterile glass beads was added between the organisms and the sand column above; simulating air-filled gaps in soil. [Ring-U-14C]-diuron was mixed into the sand to a concentration of 100 μg diuron kg-1. Degradation was measured as the amount of 14C......-diuron mineralized and as 14C residues in the sand at experimental termination. Mineralization results established the three-member consortium LEJ702/SRS16/D47 as the most efficient transforming 32% of the diuron to 14CO2, while the single strains or other consortia mineralized no more than 10%. Furthermore...... in groundwater contamination. New technologies are therefore needed for cleaning up contaminated soil and water resources. This PhD was part of the project entitled Microbial Remediation of Contaminated Soil and Water Resources (MIRESOWA) where the overall aim is to develop new technologies for bioremediation...

  14. USING PHYTOREMEDIATION AND BIOREMEDIATION FOR PROTECTION SOIL NEAR GRAVEYARD

    Directory of Open Access Journals (Sweden)

    Katarzyna Ignatowicz

    2016-07-01

    Full Text Available The aim of present research was to assess the usefulness of Basket willow (Salix viminalis to phytoremediation and bioremediation of sorption subsoil contaminated with pesticides. Studies upon purification of sorption material consisting of a soil and composting sewage sludge were conducted under pot experiment conditions. The study design included control pot along with 3 other ones polluted with pesticides. The vegetation season has lasted since spring till late autumn 2015. After acclimatization, the mixture of chloroorganic pesticides was added into 3 experimental pots. After harvest, it was found that pesticide contents in sorption subsoil (from 0.0017 to 0.0087 mg kg DM were much higher than in control soil (from 0.0005 to 0.0027 mg kg DM. Achieved results initially indicate that Basket willow (Salix viminalis can be used for reclamation of soils contaminated with pesticides, particularly for vitality prolongation of sorption barrier around the pesticide burial area. In future, it would allow for applying the sorption screen around pesticide burial area, which reduces pesticide migration into the environment, and grown energetic plants – through phytoremediation – would prolong the sorbent vitality and remove pesticides from above ground parts by means of combustion.

  15. Nanoassembly of immobilized ligninolytic enzymes for biocatalysis, bioremediation, and biosensing

    Science.gov (United States)

    Kuila, Debasish; Tien, Ming; Lvov, Yuri M.; McShane, Michael J.; Aithal, Rajendra K.; Singh, Saurabh; Potluri, Avinash; Kaul, Swati; Patel, Devendra S.; Krishna, Gopal

    2004-12-01

    Extracellular enzymes, lignin peroxidase (LiP) and manganese peroxidase (MnP) from white rot fungus Phanerochaete chrysosoporium, have been shown to degrade various harmful organic compounds ranging from chlorinated compounds to polycyclic aromatic hydrocarbons (PAH) to polymeric dyes. The problems in using immobilized enzymes for biocatalysis/bioremediation are their loss of activity and long-term stability. To address these issues, adsorption by layer-by-layer assembly (LbL) using polyelectrolytes, entrapment using gelatin, and chmisorption using coupling reagents have been investigated. In order to increase surface area for catalysis, porous silicon, formed by electrochemical etching of silicon, has been considered. The efficacy of these extremely stable nanoassemblies towards degradation of model organic compounds-veratryl alcohol (VA and 2,6-dimethoxyphenol (DMP)-in aqueous and in a mixture of aqueous/acetone has already been demonstrated. In parallel, we are pursuing development of sensors using these immobilized enzymes. Experiments carried out in solution show that NO can reversibly bind Ferri-LiP to produce a diamagnetic complex with a distinct change in its optical spectrum. NO can be photolyzed off to produce the spectrum of native paramagnetic ferri-species. Preliminary data on the detection of NO by LiP, based on surface plasmon resonance (SPR) using fiber optic probe, are presented.

  16. In situ recycling of contaminated soil uses bioremediation

    International Nuclear Information System (INIS)

    OxyChem Pipeline Operations, primarily an ethylene and propylene products mover, has determined that substantial savings can be realized by adopting a bioremediation maintenance and recycling approach to hydrocarbon-contaminated soil. By this method, the soil can be recycled in situ, or in containers. To implement the soil-recycling program, OxyChem elected to use a soil remediator and natural absorbent product, Oil Snapper. This field maintenance material, based on an Enhanced Urea Technology, provides a diet to stimulate the growth of hydrocarbon-eating microbes. It works well either with indigenous soil microbes or with commercial microbes. The product is carried in field vehicles, which makes it immediately available when leaks or spills are discovered. Procedure for clean-up is to apply product and mix it into affected soil. Thus the contaminant is contained, preventing further migration; the contaminant is dispersed throughout the product, making it more accessible to the microbes; nutrients are immediately available to the microbes; and the material contributes aeration and moisture-retention properties

  17. Bioremediation of aflatoxins by some reference fungal strains.

    Science.gov (United States)

    El-Shiekh, Hussein H; Mahdy, Hesham M; El-Aaser, Mahmoud M

    2007-01-01

    Aspergillus parasiticus RCMB 002001 (2) producing four types of aflatoxins B1, B2, G1, and G2 was used in this study as an aflatoxin-producer. Penicillium griseofulvum, P. urticae, Paecilomyces lilacinus, Trichoderma viride, Candida utilis, Saccharomyces cerevisiae as well as a non-toxigenic strain of Aspergillus flavus were found to be able to exhibit growth on aflatoxin B1-containing medium up to a concentration of 500 ppb. It was also found that several fungal strains exhibited the growth in co-culture with A. parasiticus, natural aflatoxins producer, and were able to decreased the total aflatoxin concentration, resulting in the highest inhibition percentage of 67.2% by T viride, followed by P. lilacinus, P. griseofulvum, S. cerevisiae, C. utilis, P. urticae, Rhizopus nigricans and Mucor rouxii with total aflatoxin inhibition percentage of 53.9, 52.4, 52, 51.7, 44, 38.2 and 35.4%, respectively. The separation of bioremediation products using GC/MS revealed that the toxins were degraded into furan moieties.

  18. Aspergillus flavus: A potential Bioremediator for oil contaminated soils

    Directory of Open Access Journals (Sweden)

    Y.Avasn Maruthi

    2013-02-01

    Full Text Available Biodegradation is cost-effective, environmentally friendly treatment for oily contaminated sites by the use of microorganisms. In this study, laboratory experiments were conducted to establish the performance of fungal isolates in degradation of organic compounds contained in soils contaminated with petrol and diesel. As a result of the laboratory screening, two natural fungal strains capable of degrading total organic carbons (TOC were prepared from isolates enriched from the oil contaminated sites. Experiments were conducted in Erlenmeyer flasks under aerobic conditions, with TOC removal percentage varied from 0.7 to 32% depending on strains type and concentration. Strains Phanerocheate chrysosporium and Aspergillus niger exhibited the highest TOC removal percentage of 32 and 21%, respectively, before nutrient addition. TOC removal rate was enhanced after addition of nutrients to incubated flasks. The highest TOC reduction (45% was estimated after addition of combination of nitrogen, phosphorus and sulphur to Phanerocheate chrysosporium strains. Results of experimental work carried out elucidate that the fungi like Phanerocheate chrysosporium and Aspergillus niger were capabled of producing enzymes at a faster rate to decompose the substrate hydrocarbon and released more CO2 and hence these potential fungi can be utilized effectively as agents of biodegradation in waste recycling process and Bioremediation of oil contaminated sites.

  19. Feasibility of electrokinetic oxygen supply for soil bioremediation purposes.

    Science.gov (United States)

    Mena Ramírez, E; Villaseñor Camacho, J; Rodrigo Rodrigo, M A; Cañizares Cañizares, P

    2014-12-01

    This paper studies the possibility of providing oxygen to a soil by an electrokinetic technique, so that the method could be used in future aerobic polluted soil bioremediation treatments. The oxygen was generated from the anodic reaction of water electrolysis and transported to the soil in a laboratory-scale electrokinetic cell. Two variables were tested: the soil texture and the voltage gradient. The technique was tested in two artificial soils (clay and sand) and later in a real silty soil, and three voltage gradients were used: 0.0 (control), 0.5, and 1.0 V cm(-1). It was observed that these two variables strongly influenced the results. Oxygen transport into the soil was only available in the silty and sandy soils by oxygen diffusion, obtaining high dissolved oxygen concentrations, between 4 and 9 mg L(-1), useful for possible aerobic biodegradation processes, while transport was not possible in fine-grained soils such as clay. Electro-osmotic flow did not contribute to the transport of oxygen, and an increase in voltage gradients produced higher oxygen transfer rates. However, only a minimum fraction of the electrolytically generated oxygen was efficiently used, and the maximum oxygen transport rate observed, approximately 1.4 mgO2 L(-1)d(-1), was rather low, so this technique could be only tested in slow in-situ biostimulation processes for organics removal from polluted soils.

  20. The bioremediation potential of marine sandy sediment microbiota

    Directory of Open Access Journals (Sweden)

    Dan Răzvan POPOVICIU

    2012-11-01

    Full Text Available The natural microbiota from marine sandy sediments on the Romanian sea coast was tested for resilience in case of hydrocarbon contamination, for estimating the number of (culturable hydrocarbon and lipid oil-degrading microorganisms and for determining the influence of inorganic nitrate and phosphate nutrients on hydrocarbon spill bioremediation process, by microcosm experiments.Results show that hydrocarbon contamination affects the bacteriobenthos both in terms of cell numbers and composition. Bacterial numbers showed a rapid decrease (28% in four days, followed by a relatively fast recovery (two weeks. The pollution favoured the increase of Gram-positive bacterial proportion (from around 25% to 33%Sandy sediment microbiota in both sites studied contained microorganisms able to use mineral or lipid oils as sole carbon sources, usually around 103-104/cm3, with variations according to the sediment grain size and substrate used.The biostimulation experiments showed that, in absence of water dynamism (and, implicitly, an efficient oxygenation, the addition of nitrogen and phosphorus can be ineffective and even inhibit the remediation process, probably due to eutrophication.

  1. Bioremediation of the textile waste effluent by Chlorella vulgaris

    Directory of Open Access Journals (Sweden)

    Hala Yassin El-Kassas

    2014-01-01

    Full Text Available The microalgae biomass production from textile waste effluent is a possible solution for the environmental impact generated by the effluent discharge into water sources. The potential application of Chlorella vulgaris for bioremediation of textile waste effluent (WE was investigated using 22 Central Composite Design (CCD. This work addresses the adaptation of the microalgae C. vulgaris in textile waste effluent (WE and the study of the best dilution of the WE for maximum biomass production and for the removal of colour and Chemical Oxygen Demand (COD by this microalga. The cultivation of C. vulgaris, presented maximum cellular concentrations Cmax and maximum specific growth rates μmax in the wastewater concentration of 5.0% and 17.5%, respectively. The highest colour and COD removals occurred with 17.5% of textile waste effluent. The results of C. vulgaris culture in the textile waste effluent demonstrated the possibility of using this microalga for the colour and COD removal and for biomass production. There was a significant negative relationship between textile waste effluent concentration and Cmax at 0.05 level of significance. However, sodium bicarbonate concentration did not significantly influence the responses of Cmax and the removal of colour and COD.

  2. Bioremediation of an area contaminated by a fuel spill.

    Science.gov (United States)

    Vallejo, B; Izquierdo, A; Blasco, R; Pérez del Campo, P; Luque de Castro, M D

    2001-06-01

    In order to decontaminate a large area of restricted access contaminated by a fuel spill, laboratory and field studies were developed in two steps: (a) monitoring of the laboratory experiment on bacterial growth under aerobic and anaerobic conditions with and without addition of nutrients; and (b) use of the best conditions obtained in (a) for the decontamination of the soil. A hydraulic barrier was installed both to clean the aquifer and to avoid migration of hydrocarbons as a consequence of their solution in the groundwater and subsequent displacement. The objective was to create an ideal environment for the treatment of the affected area that favoured the growth of the indigenous bacteria (Pseudomonas and Arthrobacter) that biodegrade the hydrocarbons. Monitoring of the changes in the total concentration of petroleum hydrocarbons in the soil subjected to bacterial action was performed by gas chromatography. In a field study, the progress of biodegradation of hydrocarbons was evaluated in situ by changes in subsurface CO2/O2 levels by means of an analyser equipped with an infrared detector. Biostimulation and oxygen were the most influential factors for the biodegradation of the hydrocarbons. The use of bioventing of the soil was shown as an excellent technology to promote in situ bioremediation of the polluted area.

  3. Searching bioremediation patents through Cooperative Patent Classification (CPC).

    Science.gov (United States)

    Prasad, Rajendra

    2016-03-01

    Patent classification systems have traditionally evolved independently at each patent jurisdiction to classify patents handled by their examiners to be able to search previous patents while dealing with new patent applications. As patent databases maintained by them went online for free access to public as also for global search of prior art by examiners, the need arose for a common platform and uniform structure of patent databases. The diversity of different classification, however, posed problems of integrating and searching relevant patents across patent jurisdictions. To address this problem of comparability of data from different sources and searching patents, WIPO in the recent past developed what is known as International Patent Classification (IPC) system which most countries readily adopted to code their patents with IPC codes along with their own codes. The Cooperative Patent Classification (CPC) is the latest patent classification system based on IPC/European Classification (ECLA) system, developed by the European Patent Office (EPO) and the United States Patent and Trademark Office (USPTO) which is likely to become a global standard. This paper discusses this new classification system with reference to patents on bioremediation. PMID:26812756

  4. Bioremediation of aflatoxins by some reference fungal strains.

    Science.gov (United States)

    El-Shiekh, Hussein H; Mahdy, Hesham M; El-Aaser, Mahmoud M

    2007-01-01

    Aspergillus parasiticus RCMB 002001 (2) producing four types of aflatoxins B1, B2, G1, and G2 was used in this study as an aflatoxin-producer. Penicillium griseofulvum, P. urticae, Paecilomyces lilacinus, Trichoderma viride, Candida utilis, Saccharomyces cerevisiae as well as a non-toxigenic strain of Aspergillus flavus were found to be able to exhibit growth on aflatoxin B1-containing medium up to a concentration of 500 ppb. It was also found that several fungal strains exhibited the growth in co-culture with A. parasiticus, natural aflatoxins producer, and were able to decreased the total aflatoxin concentration, resulting in the highest inhibition percentage of 67.2% by T viride, followed by P. lilacinus, P. griseofulvum, S. cerevisiae, C. utilis, P. urticae, Rhizopus nigricans and Mucor rouxii with total aflatoxin inhibition percentage of 53.9, 52.4, 52, 51.7, 44, 38.2 and 35.4%, respectively. The separation of bioremediation products using GC/MS revealed that the toxins were degraded into furan moieties. PMID:18062656

  5. Bioremediation of petroleum hydrocarbons: catabolic genes, microbial communities, and applications.

    Science.gov (United States)

    Fuentes, Sebastián; Méndez, Valentina; Aguila, Patricia; Seeger, Michael

    2014-06-01

    Bioremediation is an environmental sustainable and cost-effective technology for the cleanup of hydrocarbon-polluted soils and coasts. In spite of that longer times are usually required compared with physicochemical strategies, complete degradation of the pollutant can be achieved, and no further confinement of polluted matrix is needed. Microbial aerobic degradation is achieved by the incorporation of molecular oxygen into the inert hydrocarbon molecule and funneling intermediates into central catabolic pathways. Several families of alkane monooxygenases and ring hydroxylating dioxygenases are distributed mainly among Proteobacteria, Actinobacteria, Firmicutes and Fungi strains. Catabolic routes, regulatory networks, and tolerance/resistance mechanisms have been characterized in model hydrocarbon-degrading bacteria to understand and optimize their metabolic capabilities, providing the basis to enhance microbial fitness in order to improve hydrocarbon removal. However, microbial communities taken as a whole play a key role in hydrocarbon pollution events. Microbial community dynamics during biodegradation is crucial for understanding how they respond and adapt to pollution and remediation. Several strategies have been applied worldwide for the recovery of sites contaminated with persistent organic pollutants, such as polycyclic aromatic hydrocarbons and petroleum derivatives. Common strategies include controlling environmental variables (e.g., oxygen availability, hydrocarbon solubility, nutrient balance) and managing hydrocarbon-degrading microorganisms, in order to overcome the rate-limiting factors that slow down hydrocarbon biodegradation.

  6. Potential of Penicillium Species in the Bioremediation Field

    Directory of Open Access Journals (Sweden)

    Ana Lúcia Leitão

    2009-04-01

    Full Text Available 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.

  7. Apparatus and method for phosphate-accelerated bioremediation

    Science.gov (United States)

    Looney, B.B.; Phelps, T.J.; Hazen, T.C.; Pfiffner, S.M.; Lombard, K.H.; Borthen, J.W.

    1994-01-01

    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.

  8. Microbial aspects of acid mine drainage and its bioremediation

    Institute of Scientific and Technical Information of China (English)

    K.A.NATARAJAN

    2008-01-01

    The role of chemolithotrophs such as Acidithiobacillus ferrooxidans,Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans which were isolated from some abandoned mines and processed waste tailings in the generation of acid mine drainage and toxic metal dissolution was discussed.Mechanisms of acid formation and dissolution of copper,zinc,iron and arsenic from copper,lead-zinc and arsenopyrite-bearing sulfide ores and tailings were established in the presence of Acidithiobacillus group of bacteria.Sulphate Reducing Bacteria(SRB) isolated from the above mine sites could be used to precipitate dissolved metals such as copper,zinc,iron and arsenic.Arsenic bioremediation was demonstrated through the use of native microorganisms such Thiomonas spp.which could oxidize arsenite to arsenate.Bioremoval of arsenic through the use of jarosite precipitates generated by Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans was also found to be very effective.Biotechnological processes hold great promise in the remediation of acid mine drainage and efficient removal of toxic metal ions such as copper,zinc and arsenic.

  9. Testing the efficacy of oil spill bioremediation products

    International Nuclear Information System (INIS)

    Ten bioremediation products were tested in laboratory respirometers for their ability to enhance the biodegradation of artificially weathered Alaska North Slope crude oil compared to natural populations supplied with mineral nutrients. The sea water used was natural sea water obtained from the Gulf of Mexico near Gulf Breeze, Florida. All products were tested in triplicate in closed laboratory flasks connected to an instrument able to track and record cumulative oxygen uptake continuously over time. Triplicate flasks were sacrificed periodically, the contents extracted with hexane, and the oil components quantified by gas chromatography/mass spectrometry (GC/MS). Correlations were made between the decline in aliphatic and aromatic analytes and the net oxygen uptake observed in each flask. From these correlations, the median time needed to consume enough oxygen to effect a 6O percent decline in the total resolved analytes was computed for each product, and this time was compared statistically to the time needed by the natural populations in the source sea water to effect the same removal. Using this approach, five of the ten products were found to enhance biotransformation of the crude oil analytes. When the analysis was repeated for the aromatic constituents only, using a target removal of only 25 percent, only two of the ten products gave shorter response times than the nutrient-supplemented sea water

  10. Bioremediation of polyaromatic hydrocarbons (PAHs using rhizosphere technology

    Directory of Open Access Journals (Sweden)

    Sandeep Bisht

    2015-03-01

    Full Text Available The remediation of polluted sites has become a priority for society because of increase in quality of life standards and the awareness of environmental issues. Over the past few decades there has been avid interest in developing in situ strategies for remediation of environmental contaminants, because of the high economic cost of physicochemical strategies, the biological tools for remediation of these persistent pollutants is the better option. Major foci have been considered on persistent organic chemicals i.e.polyaromatic hydrocarbons (PAHs due to their ubiquitous occurrence, recalcitrance, bioaccumulation potential and carcinogenic activity. Rhizoremediation, a specific type of phytoremediation that involves both plants and their associated rhizospheric microbes is the creative biotechnological approach that has been explored in this review. Moreover, in this review we showed the significance of rhizoremediation of PAHs from other bioremediation strategies i.e. natural attenuation, bioaugmentation and phytoremediation and also analyze certain environmental factor that may influence the rhizoremediation technique. Numerous bacterial species were reported to degrade variety of PAHs and most of them are isolated from contaminated soil, however few reports are available from non contaminated soil. Pseudomonas aeruginosa, Pseudomons fluoresens, Mycobacterium spp., Haemophilus spp., Rhodococcus spp., Paenibacillus spp. are some of the commonly studied PAH-degrading bacteria. Finally, exploring the molecular communication between plants and microbes, and exploiting this communication to achieve better results in the elimination of contaminants, is a fascinating area of research for future perspective.

  11. Proteogenomic monitoring of Geobacter physiology during stimulated uranium bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Wilkins, M.J.; VerBerkmoes, N.C.; Williams, K.H.; Callister, S.J.; Mouser, P.J.; Elifantz, H.; N' Guessan, A.L.; Thomas, B.C.; Nicora, C.D.; Shah, M.B.; Lipton, M.S.; Lovley, D.R.; Hettich, R.L.; Long, P.E.; Banfield, J.F.; Abraham, P.

    2009-08-01

    Implementation of uranium bioremediation requires methods for monitoring the membership and activities of the subsurface microbial communities that are responsible for reduction of soluble U(VI) to insoluble U(IV). Here, we report a proteomics-based approach for simultaneously documenting the strain membership and microbial physiology of the dominant Geobacter community members during in situ acetate amendment of the U-contaminated Rifle, CO, aquifer. Three planktonic Geobacter-dominated samples were obtained from two wells down-gradient of acetate addition. Over 2,500 proteins from each of these samples were identified by matching liquid chromatography-tandem mass spectrometry spectra to peptides predicted from seven isolate Geobacter genomes. Genome-specific peptides indicate early proliferation of multiple M21 and Geobacter bemidjiensis-like strains and later possible emergence of M21 and G. bemidjiensis-like strains more closely related to Geobacter lovleyi. Throughout biostimulation, the proteome is dominated by enzymes that convert acetate to acetyl-coenzyme A and pyruvate for central metabolism, while abundant peptides matching tricarboxylic acid cycle proteins and ATP synthase subunits were also detected, indicating the importance of energy generation during the period of rapid growth following the start of biostimulation. Evolving Geobacter strain composition may be linked to changes in protein abundance over the course of biostimulation and may reflect changes in metabolic functioning. Thus, metagenomics-independent community proteogenomics can be used to diagnose the status of the subsurface consortia upon which remediation biotechnology relies.

  12. Acoustic Similarity and Dichotic Listening.

    Science.gov (United States)

    Benson, Peter

    1978-01-01

    An experiment tests conjectures that right ear advantage (REA) has an auditory origin in competition or interference between acoustically similar stimuli and that feature-sharing effect (FSE) has its origin in assignment of features of phonetically similar stimuli. No effect on the REA for acoustic similarity, and a clear effect of acoustic…

  13. Functional Similarity and Interpersonal Attraction.

    Science.gov (United States)

    Neimeyer, Greg J.; Neimeyer, Robert A.

    1981-01-01

    Students participated in dyadic disclosure exercises over a five-week period. Results indicated members of high functional similarity dyads evidenced greater attraction to one another than did members of low functional similarity dyads. "Friendship" pairs of male undergraduates displayed greater functional similarity than did "nominal" pairs from…

  14. Change of isoprenoids, steranes and terpanes during ex situ bioremediation of mazut on industrial level

    Directory of Open Access Journals (Sweden)

    Beškoski Vladimir P.

    2010-01-01

    Full Text Available The paper presents results of the ex situ bioremediation of soil contaminated by mazut (heavy residual fuel oil in the field scale (600 m3. A treatment-bed (thickness 0.4 m consisted of mechanically mixed mazut-contaminated soil, softwood sawdust as the additional carbon source and crude river sand, as bulking and porosity increasing material. The inoculation/reinoculation was conducted periodically using a biomass of a consortium of zymogenous microorganisms isolated from the bioremediation substrate. The biostimulation was performed through addition of nutritious substances (N, P and K. The aeration was improved by systematic mixing of the bioremediation system. After 50 days, the number of hydrocarbon degraders increased 100 times. Based on the changes in the group composition, the average biodegradation rate during bioremediation was 24 mg/kg/day for the aliphatic fraction, 6 mg/kg/day for the aromatic fraction, and 3 mg/kg/day for the nitrogen-sulphuroxygen compounds (NSO-asphaltene fraction. In the saturated hydrocarbon fraction, gas chromatography-mass spectrometry (GC-MS in the single ion-monitoring mode (SIM was applied to analyse isoprenoids pristane and phytane and polycyclic molecules of sterane and triterpane type. Biodegradation occurred during the bioremediation process, as well as reduction of relative quantities of isoprenoids, steranes, tri- and tetracyclic terpanes and pentacyclic terpanes of hopane type.

  15. Investigation of the bioremediation potential of aerobic zymogenous microorganisms in soil for crude oil biodegradation

    Directory of Open Access Journals (Sweden)

    TATJANA ŠOLEVIĆ

    2011-03-01

    Full Text Available The bioremediation potential of the aerobic zymogenous microorganisms in soil (Danube alluvium, Pančevo, Serbia for crude oil biodegradation was investigated. A mixture of paraffinic types of oils was used as the substrate. The laboratory experiment of the simulated oil biodegradation lasted 15, 30, 45, 60 and 75 days. In parallel, an experiment with a control sample was conducted. Extracts were isolated from the samples with chloroform in a separation funnel. From these extracts, the hydrocarbons were isolated by column chromatography and analyzed by gas chromatography–mass spectrometry (GC–MS. n-Alkanes, isoprenoids, phenanthrene and its derivatives with one and two methyl groups were quantitatively analyzed. The ability and efficiency of zymogenous microorganisms in soil for crude oil bioremediation was assessed by comparison between the composition of samples which were exposed to the microorganisms and the control sample. The investigated microorganisms showed the highest bioremediation potential in the biodegradation of n-alkanes and isoprenoids. A considerably high bioremediation potential was confirmed in the biodegradation of phenanthrene and methyl phenanthrenes. Low bioremediation potential of these microorganisms was proven in the case of polycyclic alkanes of the sterane and triterpane types and dimethyl phenanthrenes.

  16. PROSPECTIVE IN-SILCO APPROACH IN BIOREMEDIATION OF PETROLEUM HYDROCARBON: SUCCESS SO FAR

    Directory of Open Access Journals (Sweden)

    Mohammad Nadeem Khan

    2013-06-01

    Full Text Available Bioremediation has the potential to reduce contaminated environment inexpensively yet effectively. But, the lack of information about the factors controlling the growth and metabolism in microorganisms in polluted environment often limits its implementation. However rapid advances in the understanding of bioremediation are on the horizon. With advances in biotechnology, bioremediation has become one of the most rapidly developing fields of environmental restoration, utilizing microorganisms to reduce the concentration and toxicity of various chemical pollutants, such as petroleum hydrocarbons. In this mini-review, the current state of the field is described and the role of synthetic biology in biotechnology in short and medium term is discussed. A number of bioremediation strategies have been developed to treat contaminated wastes and sites. Selecting the most appropriate strategy to treat a specific site can be guided by considering three basic principles: the amenability of the pollutant to biological transformation to less toxic products, the bioavailability of the contaminant to microorganisms and the opportunity for bioprocess optimization. By the recent advances on in-silico dimensions of bioremediation, it seems that the synthetic biology software will soon drive the wet-lab implementation at molecular level.

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

    Science.gov (United States)

    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.

  18. Effectiveness of bioremediation for the Prestige fuel spill : a summary of case studies

    Energy Technology Data Exchange (ETDEWEB)

    Gallego, J.R. [Oviedo Univ., Asturias (Spain); Gonzalez-Rojas, E.; Pelaez, A.I.; Sanchez, J [Oviedo Univ., Asturias (Spain). Inst. de Biotecnologia de Asturias; Garcia-Martinez, M.J.; Llamas, J.F. [Univ. Polictenica de Madrid, Madrid (Spain). Laboratorio de Estratigrafia Biomolecular

    2006-07-01

    This paper described novel bioremediation strategies used to remediate coastal areas in Spain impacted by the Prestige fuel oil spill in 2002. The bioremediation techniques were applied after hot pressurized water washing was used to remove hydrocarbons adhering to shorelines and rocks. Bioremediation strategies included monitored natural attenuation as well as accelerating biodegradation by stimulating indigenous populations through the addition of exogenous microbial populations. The sites selected for bioremediation were rocky shorelines of heterogenous granitic sediments with grain sizes ranging from sands to huge boulders; limestone-sandstone pebbles and cobbles; and fuel-coated limestone cliffs. Total surface area covered by the fuel was determined through the use of image analysis calculations. A statistical measurement of the fuel layer thickness was calculated by averaging the weights of multiple-fuel sampling increments. Bioremediation products included the use of oleophilic fertilizers; a biodegradable surfactant; and a microbial seeding agent. Determinations of saturate, aromatic, resins, and asphaltene (SARA) were performed using maltenes extraction and liquid chromatography. Microbial plating and selective enrichment with fuel as the sole carbon source were used to monitor the evolution of microbial populations in a variety of experiments. It was concluded that the biostimulation technique enhanced the efficiency of the in situ oleophilic fertilizers. 17 refs., 2 tabs., 6 figs.

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

    Science.gov (United States)

    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

  20. Effectiveness of bioremediation for the Prestige fuel spill : a summary of case studies

    International Nuclear Information System (INIS)

    This paper described novel bioremediation strategies used to remediate coastal areas in Spain impacted by the Prestige fuel oil spill in 2002. The bioremediation techniques were applied after hot pressurized water washing was used to remove hydrocarbons adhering to shorelines and rocks. Bioremediation strategies included monitored natural attenuation as well as accelerating biodegradation by stimulating indigenous populations through the addition of exogenous microbial populations. The sites selected for bioremediation were rocky shorelines of heterogenous granitic sediments with grain sizes ranging from sands to huge boulders; limestone-sandstone pebbles and cobbles; and fuel-coated limestone cliffs. Total surface area covered by the fuel was determined through the use of image analysis calculations. A statistical measurement of the fuel layer thickness was calculated by averaging the weights of multiple-fuel sampling increments. Bioremediation products included the use of oleophilic fertilizers; a biodegradable surfactant; and a microbial seeding agent. Determinations of saturate, aromatic, resins, and asphaltene (SARA) were performed using maltenes extraction and liquid chromatography. Microbial plating and selective enrichment with fuel as the sole carbon source were used to monitor the evolution of microbial populations in a variety of experiments. It was concluded that the biostimulation technique enhanced the efficiency of the in situ oleophilic fertilizers. 17 refs., 2 tabs., 6 figs

  1. J.R. SIMPLOT EX-SITU BIOREMEDIATION TECHNOLOGY FOR TREATMENT OF TNT-CONTAMINATED SOILS - INNOVATIVE TECHNOLOGY EVALUATION REPORT

    Science.gov (United States)

    This report summarizes the findings of the second evaluation of the J.R. Simplot Ex-situ Bioremediation Technology also known as the Simplot Anaerobic Bioremediation (SABRE™) process. This technology was developed by the J.R. Simplot Company to biologically degrade nitroaromatic...

  2. Evaluation of biodiesel as bioremediation agent for the treatment of the shore affected by the heavy oil spill of the Prestige

    International Nuclear Information System (INIS)

    The efficiency of different bioremediation products (nutrients, microorganisms and biodiesel) was tested using tiles located in both the supra-littoral and intertidal zones of a beach that was affected by the heavy oil spill of the Prestige. Neither nutrients nor microorganisms meant an improvement with respect to the natural processes. The addition of biodiesel improved the appearance of the treated tiles and apparently accelerated the degradation of the aliphatic and aromatic fractions of the residual fuel oil. Nevertheless, PAHs degradation was similar and very high in all the treatments (80-85% after 60 days). On the other hand, the evolution with time of the amount of vanadium was similar to that of 17α(H),21β(H)-hopane, so it was concluded that vanadium could also be used to estimate the extent of oil degradation in the field. These results also suggested that the residual fuel oil mineralization was very low throughout 1 year in all the treatments. Moreover, the increase of the oxygen content of the residual oil from around 1% till 4-8% indicated that the partial oxidation of hydrocarbons took place, and that the hydrocarbon oxidation products accumulated in the polar fractions. In general, the results pointed out that bioremediation techniques were not suitable for the recovery of shores affected by heavy oil spills

  3. Image fusion using bi-directional similarity

    Science.gov (United States)

    Bai, Chunshan; Luo, Xiaoyan

    2015-05-01

    Infrared images are widely used in the practical applications to capture abundant information. However, it is still challenging to enhance the infrared image by the visual image. In this paper, we propose an effective method using bidirectional similarity. In the proposed method, we aim to find an optimal solution from many feasible solutions without introducing intermediate image. We employ some priori constraints to meet the requirements of image fusion which can be detailed to preserve both good characteristics in the infrared image and spatial information in the visual image. In the iterative step, we use the matrix with the square of the difference between images to integrate the image holding most information. We call this matrix the bidirectional similarity distance. By the bidirectional similarity distance, we can get the transitive images. Then, we fuse the images according to the weight. Experimental results show that, compared to the traditional image fusion algorithm, fusion images from bidirectional similarity fusion algorithm have greatly improved in the subjective vision, entropy, structural similarity index measurement. We believe that the proposed scheme can have a wide applications.

  4. Test plan for the soils facility demonstration: A petroleum contaminated soil bioremediation facility

    International Nuclear Information System (INIS)

    The objectives of this test plan are to show the value added by using bioremediation as an effective and environmentally sound method to remediate petroleum contaminated soils (PCS) by: demonstrating bioremediation as a permanent method for remediating soils contaminated with petroleum products; establishing the best operating conditions for maximizing bioremediation and minimizing volatilization for SRS PCS during different seasons; determining the minimum set of analyses and sampling frequency to allow efficient and cost-effective operation; determining best use of existing site equipment and personnel to optimize facility operations and conserve SRS resources; and as an ancillary objective, demonstrating and optimizing new and innovative analytical techniques that will lower cost, decrease time, and decrease secondary waste streams for required PCS assays

  5. Numerical simulations in support of the in situ bioremediation demonstration at Savannah River

    International Nuclear Information System (INIS)

    This report assesses the performance of the in situ bioremediation technology demonstrated at the Savannah River Integrated Demonstration (SRID) site in 1992--1993. The goal of the technology demonstration was to stimulate naturally occurring methanotrophic bacteria at the SRID site with injection of methane, air and air-phase nutrients (nitrogen and phosphate) such that significant amounts of the chlorinated solvent present in the subsurface would be degraded. Our approach is based on site-specific numerical simulations using the TRAMP computer code. In this report, we discuss the interactions among the physical and biochemical processes involved in in situ bioremediation. We also investigate improvements to technology performance, make predictions regarding the performance of this technology over long periods of time and at different sites, and compare in situ bioremediation with other remediation technologies

  6. Test plan for the soils facility demonstration: A petroleum contaminated soil bioremediation facility

    Energy Technology Data Exchange (ETDEWEB)

    Lombard, K.H.

    1994-08-01

    The objectives of this test plan are to show the value added by using bioremediation as an effective and environmentally sound method to remediate petroleum contaminated soils (PCS) by: demonstrating bioremediation as a permanent method for remediating soils contaminated with petroleum products; establishing the best operating conditions for maximizing bioremediation and minimizing volatilization for SRS PCS during different seasons; determining the minimum set of analyses and sampling frequency to allow efficient and cost-effective operation; determining best use of existing site equipment and personnel to optimize facility operations and conserve SRS resources; and as an ancillary objective, demonstrating and optimizing new and innovative analytical techniques that will lower cost, decrease time, and decrease secondary waste streams for required PCS assays.

  7. ASSESSMENT OF DISTILLERY EFFLUENT IRRIGATION ON SOIL MICROBES AND ITS BIOREMEDIATION

    Directory of Open Access Journals (Sweden)

    Tripathi D. M

    2014-12-01

    Full Text Available The present study deals with the assessment of toxicity of distillery effluent on soil microorganisms and its quality improvement through bioremediation using Pseudomonas spp. Under lab scale experiment, different dilutions of distillery effluent i.e. 25%, 50%, 75% were used to examine effects on physico-chemical parameters of effluent and on soil microflora e.g. algae, bacteria, fungi and actinomycetes. The results revealed that dilution may reduce significantly the metal contents and other toxicants in the effluent as well as in the soil. Statistical analysis revealed that bioremediation of distillery effluent using Pseudomonas spp. caused significant reduction in BOD, COD, TDS, TN, TP and color. The study indicates that raw distillery effluent is harmful for soil microflora and bioremediation improves the quality of distillery effluent making it suitable as a soil amendment.

  8. Applicability and Limits of Bioremediation of Contaminated Groundwater by Organic Compounds

    Institute of Scientific and Technical Information of China (English)

    Taboure Aboubacar; Lin Xueyu

    2001-01-01

    This paper gives in some ways a broad look at the Bioremediation Technology in the treatment of polluted groundwater. Environmentalists and Hydrologeologists around the world, especially in the developed countries welcomed this revolutionizing technique at a moment when other methods were becoming rather expensive and sources of secondary and more challenging pollution problems across sole fresh groundwater. Bioremediation of contaminated groundwater is based on the use of bacteria which breakdown organic matters to more stable forms, which will not create nuisance or give off foul odors. The Applicability of this technology at a specific site lies in the understanding of the site's hydrogeologic, physiochemical backgrounds and the knowledge of the properties of the designated bacteria colonies, which would likely stabilize the contaminants. These are key points, which determine the success of the all process. Only, by complying with all those measures, Bioremediation can meet all the expectations.

  9. Brevibacterium frigoritolerans as a Novel Organism for the Bioremediation of Phorate.

    Science.gov (United States)

    Jariyal, Monu; Gupta, V K; Mandal, Kousik; Jindal, Vikas

    2015-11-01

    Phorate, an organophosphorus insecticide, has been found effective for the control of various insect pests. However, it is an extremely hazardous insecticide and causes a potential threat to ecosystem. Bioremediation is a promising approach to degrade the pesticide from the soil. The screening of soil from sugarcane fields resulted in identification of Brevibacterium frigoritolerans, a microorganism with potential for phorate bioremediation was determined. B. frigoritolerans strain Imbl 2.1 resulted in the active metabolization of phorate by between 89.81% and 92.32% from soils amended with phorate at different levels (100, 200, 300 mg kg(-1) soil). But in case of control soil, 33.76%-40.92% degradation were observed. Among metabolites, sulfone was found as the main metabolite followed by sulfoxide. Total phorate residues were not found to follow the first order kinetics. This demonstrated that B. frigoritolerans has potential for bioremediation of phorate both in liquid cultures and agricultural soils. PMID:26205232

  10. Microorganism as a tool of bioremediation technology for cleaning environment: A review

    Directory of Open Access Journals (Sweden)

    Ravindra Singh

    2014-03-01

    Full Text Available The term bioremediation has been introduced to describe the process of using biological agents to remove toxic waste from environment. Bioremediation is the most effective management tool to manage the polluted environment and recover contaminated soil. The hazardous wastes generated from the chemical processes/operations are being treated using physico-chemical and biological methods by the respective industries to meet the prescribed standard as per the Environmental Protection Act, 1986. The wastes treated by the respective industries are collected at Common Effluent Treatment Plant, before discharge into the environment. After the treatment of collected waste at Common Effluent Treatment Plant, the solid and treated effluents are segregated and disposed of into the soil- water environment. In spite of the present treatment technology, the organic pollutants are found persisting in the soil-water environment above their acceptable level. Hence, bioremediation is an innovative technology that has the potential to alleviate the toxic contamination.

  11. Dynamism of PGPR in bioremediation and plant growth promotion in heavy metal contaminated soil.

    Science.gov (United States)

    Patel, P R; Shaikh, S S; Sayyed, R Z

    2016-04-01

    Heavy metal contamination, particularly of cultivable lands, is a matter of concern. Bioremediation helps in reversing such contamination to certain extent. Here, we report isolation, polyphasic identification and the role of siderophore producing rhizobacteria Alcaligenes feacalis RZS2 and Pseudomonas aeruginosa RZS3 in bioremediation of heavy metal contaminated soil and plant growth promotion activity in such contaminated soil. Siderophore produced by A. feacalis RZS2 and P. aeruginosa RZS3 strains chelated various heavy metal ions like MnCl₂.4H₂O, NiCl₂.6H₂O, ZnCl₂, CuCl₂ and CoCl₂ other than FeCl₃.6H2O at batch scale. Their bioremediation potential was superior over the chemical ion chelators like EDTA and citric acid. These isolates also promoted growth of wheat and peanut seeds sown in heavy metal contaminated soil. Effective root colonizing ability of these isolates was observed in wheat and peanut plants.

  12. Brevibacterium frigoritolerans as a Novel Organism for the Bioremediation of Phorate.

    Science.gov (United States)

    Jariyal, Monu; Gupta, V K; Mandal, Kousik; Jindal, Vikas

    2015-11-01

    Phorate, an organophosphorus insecticide, has been found effective for the control of various insect pests. However, it is an extremely hazardous insecticide and causes a potential threat to ecosystem. Bioremediation is a promising approach to degrade the pesticide from the soil. The screening of soil from sugarcane fields resulted in identification of Brevibacterium frigoritolerans, a microorganism with potential for phorate bioremediation was determined. B. frigoritolerans strain Imbl 2.1 resulted in the active metabolization of phorate by between 89.81% and 92.32% from soils amended with phorate at different levels (100, 200, 300 mg kg(-1) soil). But in case of control soil, 33.76%-40.92% degradation were observed. Among metabolites, sulfone was found as the main metabolite followed by sulfoxide. Total phorate residues were not found to follow the first order kinetics. This demonstrated that B. frigoritolerans has potential for bioremediation of phorate both in liquid cultures and agricultural soils.

  13. Isolation, characterization and development of bacteria in the Mine Gafsa for applications in bioremediation

    International Nuclear Information System (INIS)

    Today pollution represents an important environmental problem. Bacterial ability to bioremediate many types of pollutants in different matrixes (soil, water, and air) have been widely acknowledged. The goal of the present work is to isolate from contaminated soil of Gafsa, in Tunisia, bacterial strains to evaluate their potential for bioremediation. Soil from the mining area of Gafsa was collected. Initially, many bacterial strains were isolated in TGY agar (Tryptone/Glucose/Yeast extract agar) based on the presence of pigments. The primary bacterial selection was performed using heavy metals and the minimal inhibitory concentrations (MICs) of a metal-resistant bacterium, Cupriavidus metallidurans CH34. Isolated metal-resistant bacterium was checked for its potential to resistant to gamma radiation. Selected strain, Micrococcus luteus S7, was assessed for its bioremediation potential of matrixes artificially contaminated under laboratory conditions for its future use in developing a bio product for contaminated soil inoculation.

  14. Bioremediation of 60Co from simulated spent decontamination solutions of nuclear power reactors by bacteria

    International Nuclear Information System (INIS)

    The spent decontamination solutions generated from nuclear power reactors contain radionuclides of cobalt (60Co, 56Co and 57Co) along with a large excess (105) of non-radioactive metal ions (Fe, Ni and Cr). Our previous studies demonstrated that bioremediation of 60Co from simulated effluents using fungal biomass can provide an alternative to conventional ion exchangers. In this study, we used several bacteria to further improve the process of bioremediation by decreasing biomass requirement and treatment period. Further, metabolite activation in specific bacterial species resulted in enhanced bioremediation of 60Co from simulated effluent. Optimization of conditions in simulated effluent for the eight bacterial species to accomplish maximum 60Co removal is discussed. (author)

  15. Approach of Bioremediation in Olive Oil and Dairy Industry: A Review

    Directory of Open Access Journals (Sweden)

    Amir Hamid

    2013-02-01

    Full Text Available Bioremediation methods are a promising way of dealing with soil and subsoil contamination by organic substances. This biodegradation process is supported by micro-organisms which use the organic carbon from the pollutants as energy source and cells building blocks. There are several advantages of the implementation of such methods but mainly they have to do with the lack of interference with the ecology of the ecosystem. This study presents the use of technique in numerous ways such as olive oil industry and dairy industry. Although the use of bioremediation technique is not innovative in food industry and microbiology. The use of herbicides, pesticides and contaminated chemicals are producing pollutant compounds in ecosystem which is effecting the environment. Bioremediation method is very constructive method to converted contaminated compounds into non contaminated compounds.

  16. Ex-situ bioremediation of Brazilian soil contaminated with plasticizers process wastes

    Directory of Open Access Journals (Sweden)

    I. D. Ferreira

    2012-03-01

    Full Text Available The aim of this research was to evaluate the bioremediation of a soil contaminated with wastes from a plasticizers industry, located in São Paulo, Brazil. A 100-kg soil sample containing alcohols, adipates and phthalates was treated in an aerobic slurry-phase reactor using indigenous and acclimated microorganisms from the sludge of a wastewater treatment plant of the plasticizers industry (11gVSS kg-1 dry soil, during 120 days. The soil pH and temperature were not corrected during bioremediation; soil humidity was corrected weekly to maintain 40%. The biodegradation of the pollutants followed first-order kinetics; the removal efficiencies were above 61% and, among the analyzed plasticizers, adipate was removed to below the detection limit. Biological molecular analysis during bioremediation revealed a significant change in the dominant populations initially present in the reactor.

  17. Learning Multi-modal Similarity

    CERN Document Server

    McFee, Brian

    2010-01-01

    In many applications involving multi-media data, the definition of similarity between items is integral to several key tasks, e.g., nearest-neighbor retrieval, classification, and recommendation. Data in such regimes typically exhibits multiple modalities, such as acoustic and visual content of video. Integrating such heterogeneous data to form a holistic similarity space is therefore a key challenge to be overcome in many real-world applications. We present a novel multiple kernel learning technique for integrating heterogeneous data into a single, unified similarity space. Our algorithm learns an optimal ensemble of kernel transfor- mations which conform to measurements of human perceptual similarity, as expressed by relative comparisons. To cope with the ubiquitous problems of subjectivity and inconsistency in multi- media similarity, we develop graph-based techniques to filter similarity measurements, resulting in a simplified and robust training procedure.

  18. Roget's Thesaurus and Semantic Similarity

    OpenAIRE

    Jarmasz, Mario; Szpakowicz, Stan

    2012-01-01

    We have implemented a system that measures semantic similarity using a computerized 1987 Roget's Thesaurus, and evaluated it by performing a few typical tests. We compare the results of these tests with those produced by WordNet-based similarity measures. One of the benchmarks is Miller and Charles' list of 30 noun pairs to which human judges had assigned similarity measures. We correlate these measures with those computed by several NLP systems. The 30 pairs can be traced back to Rubenstein ...

  19. Spatial Operations

    Directory of Open Access Journals (Sweden)

    Anda VELICANU

    2010-09-01

    Full Text Available This paper contains a brief description of the most important operations that can be performed on spatial data such as spatial queries, create, update, insert, delete operations, conversions, operations on the map or analysis on grid cells. Each operation has a graphical example and some of them have code examples in Oracle and PostgreSQL.

  20. Spatializing Time

    DEFF Research Database (Denmark)

    Thomsen, Bodil Marie Stavning

    2011-01-01

    The article analyses some of artist Søren Lose's photographic installations in which time, history and narration is reflected in the creation of allegoric, spatial relations.......The article analyses some of artist Søren Lose's photographic installations in which time, history and narration is reflected in the creation of allegoric, spatial relations....

  1. Grey Self-similar Solitary Waves in Inhomogeneous Nonlinear Media

    Institute of Scientific and Technical Information of China (English)

    LI Hua-Mei

    2009-01-01

    This paper analyzes spatial grey self-similar solitary waves propagation and collision in graded-index nonlinear waveguide amplifiers with self-focusing and self-defocusing Kerr nonlinearities.New exact self-similar solutions are found using a novel transformation and their main features are investigated by using direct computer simulations.

  2. Large Scale Bioremediation of Petroleum Hydrocarbon Contaminated Waste at Various Installations of ONGC. India: Case Studies

    Directory of Open Access Journals (Sweden)

    Ajoy Kumar Mandal

    2014-07-01

    Full Text Available In situ and ex situ bioremediation of oil contaminated effluent pits, sludge pits, oil spilled land and tank bottom, and effluent treatment plant (ETP oily sludge was carried out at Ankleshwar, Mehsana, Assam and Cauvery Asset of Oil and Natural Gas Corporation Limited (ONGC, India. The types of contaminant were heavy paraffinic, asphaltic and light crude oil and emulsified oily sludge /contaminated soil. An indigenous microbial consortium was developed by assembling four species of bacteria, isolated from various oil contaminated sites of India, which could biodegrade different fractions of total petroleum hydrocarbon (TPH of the oily waste to environment friendly end products. The said consortium was on a large scale field applied to the above oil installations and it successfully bioremediated 30,706 tonnes of different types of oily waste. In 65 case studies of different batch size of in situ and ex situ bioremediation processes, the initial TPH content varying from 69.20 to 662.70 g/kg of oily waste has been biodegraded to 5.30 – 16.90 g/kg of oily waste in a range of 2 to 33 months. Biodegradation rate varied in the range of 0.22 – 1.10 Kg TPH /day/m2 area due to the climatic condition of the treatment zone and the type of waste treated. The bioremediated soil was non-toxic and natural vegetation was found to be grown on the same ground. Successful eco-restoration of one large effluent pit of 26,000 m2 area was carried out by cultivation of local fish species after completion of bioremediation. Bioremediation technology has helped ONGC with the management of their hazardous oily wastes in an environment friendly manner. DOI: http://dx.doi.org/10.5755/j01.erem.68.2.5632

  3. Effects of bioremediation agents on oil degradation in mineral and sandy salt marsh sediments

    International Nuclear Information System (INIS)

    Although bioremediation for oil spill cleanup has received considerable attention in recent years, its satisfactory use in the cleanup of oil spills in the wetland environment is still generally untested. A study of the often most used bioremediation agents, fertiliser, microbial product and soil oxidation, as a means of enhancing oil biodegradation in coastal mineral and sandy marsh substrates was conducted in controlled greenhouse conditions. Artificially weathered south Louisiana crude oil was applied to sods of marsh (soil and intact vegetation) at the rate of 2 l m-2. Fertiliser application enhanced marsh plant growth, soil microbial populations, and oil biodegradation rate. The live aboveground biomass of Spartina alterniflora with fertiliser application was higher than that without fertiliser. The application of fertiliser significantly increased soil microbial respiration rates, indicating the potential for enhancing oil biodegradation. Bioremediation with fertiliser application significantly reduced the total targeted normal hydrocarbons (TTNH) and total targeted aromatic hydrocarbons (TTAH) remaining in the soil, by 81% and 17%, respectively, compared to those of the oil controls. TTNH/hopane and TTAAH/hopane ratios showed a more consistent reduction, further suggesting an enhancement of oil biodegradation by fertilisation. Furthermore, soil type affected oil bioremediation; the extent of fertiliser-enhanced oil biodegradation was greater for sandy (13% TTNH remaining in the treatments with fertiliser compared to the control) than for mineral soils (26% of the control), suggesting that fertiliser application was more effective in enhancing TTNH degradation in the former. Application of microbial product and soil oxidant had no positive effects on the variables mentioned above under the present experimental conditions, suggesting that microbial degraders are not limiting biodegradation in this soil. Thus, the high cost of microbial amendments during

  4. The sequential application of macroalgal biosorbents for the bioremediation of a complex industrial effluent.

    Directory of Open Access Journals (Sweden)

    Joel T Kidgell

    Full Text Available Fe-treated biochar and raw biochar produced from macroalgae are effective biosorbents of metalloids and metals, respectively. However, the treatment of complex effluents that contain both metalloid and metal contaminants presents a challenging scenario. We test a multiple-biosorbent approach to bioremediation using Fe-biochar and biochar to remediate both metalloids and metals from the effluent from a coal-fired power station. First, a model was derived from published data for this effluent to predict the biosorption of 21 elements by Fe-biochar and biochar. The modelled outputs were then used to design biosorption experiments using Fe-biochar and biochar, both simultaneously and in sequence, to treat effluent containing multiple contaminants in excess of water quality criteria. The waste water was produced during ash disposal at an Australian coal-fired power station. The application of Fe-biochar and biochar, either simultaneously or sequentially, resulted in a more comprehensive remediation of metalloids and metals compared to either biosorbent used individually. The most effective treatment was the sequential use of Fe-biochar to remove metalloids from the waste water, followed by biochar to remove metals. Al, Cd, Cr, Cu, Mn, Ni, Pb, Zn were reduced to the lowest concentration following the sequential application of the two biosorbents, and their final concentrations were predicted by the model. Overall, 17 of the 21 elements measured were remediated to, or below, the concentrations that were predicted by the model. Both metalloids and metals can be remediated from complex effluent using biosorbents with different characteristics but derived from a single feedstock. Furthermore, the extent of remediation can be predicted for similar effluents using additive models.

  5. Characterization and Transcription of Arsenic Respiration and Resistance Genes During In Situ Uranium Bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Giloteaux, L.; Holmes, Dawn E.; Williams, Kenneth H.; Wrighton, Kelly C.; Wilkins, Michael J.; Montgomery, Alison P.; Smith, Jessica A.; Orellana, Roberto; Thompson, Courtney A.; Roper, Thomas J.; Long, Philip E.; Lovley, Derek R.

    2013-02-04

    The possibility of arsenic release and the potential role of Geobacter in arsenic biogeochemistry during in situ uranium bioremediation was investigated because increased availability of organic matter has been associated with substantial releases of arsenic in other subsurface environments. In a field experiment conducted at the Rifle, CO study site, groundwater arsenic concentrations increased when acetate was added. The number of transcripts from arrA, which codes for the alpha subunit of dissimilatory As(V) reductase, and acr3, which codes for the arsenic pump protein Acr3, were determined with quantitative RT-PCR. Most of the arrA (> 60%) and acr3-1 (> 90%) sequences that were recovered were most similar to Geobacter species, while the majority of acr3-2 (>50%) sequences were most closely related to Rhodoferax ferrireducens. Analysis of transcript abundance demonstrated that transcription of acr3-1 by the subsurface Geobacter community was correlated with arsenic concentrations in the groundwater. In contrast, Geobacter arrA transcript numbers lagged behind the major arsenic release and remained high even after arsenic concentrations declined. This suggested that factors other than As(V) availability regulated transcription of arrA in situ even though the presence of As(V) increased transcription of arrA in cultures of G. lovleyi, which was capable of As(V) reduction. These results demonstrate that subsurface Geobacter species can tightly regulate their physiological response to changes in groundwater arsenic concentrations. The transcriptomic approach developed here should be useful for the study of a diversity of other environments in which Geobacter species are considered to have an important influence on arsenic biogeochemistry.

  6. Functional environmental proteomics: elucidating the role of a c-type cytochrome abundant during uranium bioremediation.

    Science.gov (United States)

    Yun, Jiae; Malvankar, Nikhil S; Ueki, Toshiyuki; Lovley, Derek R

    2016-02-01

    Studies with pure cultures of dissimilatory metal-reducing microorganisms have demonstrated that outer-surface c-type cytochromes are important electron transfer agents for the reduction of metals, but previous environmental proteomic studies have typically not recovered cytochrome sequences from subsurface environments in which metal reduction is important. Gel-separation, heme-staining and mass spectrometry of proteins in groundwater from in situ uranium bioremediation experiments identified a putative c-type cytochrome, designated Geobacter subsurface c-type cytochrome A (GscA), encoded within the genome of strain M18, a Geobacter isolate previously recovered from the site. Homologs of GscA were identified in the genomes of other Geobacter isolates in the phylogenetic cluster known as subsurface clade 1, which predominates in a diversity of Fe(III)-reducing subsurface environments. Most of the gscA sequences recovered from groundwater genomic DNA clustered in a tight phylogenetic group closely related to strain M18. GscA was most abundant in groundwater samples in which Geobacter sp. predominated. Expression of gscA in a strain of Geobacter sulfurreducens that lacked the gene for the c-type cytochrome OmcS, thought to facilitate electron transfer from conductive pili to Fe(III) oxide, restored the capacity for Fe(III) oxide reduction. Atomic force microscopy provided evidence that GscA was associated with the pili. These results demonstrate that a c-type cytochrome with an apparent function similar to that of OmcS is abundant when Geobacter sp. are abundant in the subsurface, providing insight into the mechanisms for the growth of subsurface Geobacter sp. on Fe(III) oxide and suggesting an approach for functional analysis of other Geobacter proteins found in the subsurface.

  7. Compost as a source of microbial isolates for the bioremediation of heavy metals: In vitro selection

    Energy Technology Data Exchange (ETDEWEB)

    Vargas-Garcia, Maria del Carmen, E-mail: mcvargas@ual.es; Lopez, Maria Jose, E-mail: mllopez@ual.es; Suarez-Estrella, Francisca, E-mail: fsuarez@ual.es; Moreno, Joaquin, E-mail: jcasco@ual.es

    2012-08-01

    Heavy metal pollution has become a major environmental concern nowadays and the bioremediation of polluted habitats is an increasingly popular strategy due to both its efficiency and safety. A screening and selection protocol based on different composting processes was designed in order to isolate heavy metal-resistant microorganisms. A collection of 51 microorganisms was obtained and most of them showed the capability to tolerate heavy metals in multi-polluted aqueous systems (Cd(II), Cr(VI), Ni, Pb, Zn(II)), as well as to remove them. The highest detoxification ratios were observed for Pb. Some of the isolates detoxifying more than a 90% of this metal, while the other metals were removed in a range between 20% and 60%. The best isolates (Graphium putredinis, Fusarium solani, Fusarium sp. and Penicillium chrysogenum) were further assayed in order to determine the predominant removal mechanism and the potential use of their dead biomass as a biosorbent. Intracellular accumulation was the prevalent mechanism for most isolates and metals, with the exception of Ni. In this case, the proportion removed by extracellular adsorption was similar or even higher than that removed by intracellular accumulation. Thus, the efficiency of living cells was higher than that of dead biomass except in the case of Ni. - Highlights: Black-Right-Pointing-Pointer Composting is a good reservoir for the isolation of HM-resistant microorganisms. Black-Right-Pointing-Pointer Pb was the most removed heavy metal in multi-polluted aqueous systems. Black-Right-Pointing-Pointer Intracellular accumulation was the predominant mechanism for heavy metal removal. Black-Right-Pointing-Pointer Graphium putredinis, which detoxifies organic pollutants, was the most efficient isolate.

  8. Functional environmental proteomics: elucidating the role of a c-type cytochrome abundant during uranium bioremediation.

    Science.gov (United States)

    Yun, Jiae; Malvankar, Nikhil S; Ueki, Toshiyuki; Lovley, Derek R

    2016-02-01

    Studies with pure cultures of dissimilatory metal-reducing microorganisms have demonstrated that outer-surface c-type cytochromes are important electron transfer agents for the reduction of metals, but previous environmental proteomic studies have typically not recovered cytochrome sequences from subsurface environments in which metal reduction is important. Gel-separation, heme-staining and mass spectrometry of proteins in groundwater from in situ uranium bioremediation experiments identified a putative c-type cytochrome, designated Geobacter subsurface c-type cytochrome A (GscA), encoded within the genome of strain M18, a Geobacter isolate previously recovered from the site. Homologs of GscA were identified in the genomes of other Geobacter isolates in the phylogenetic cluster known as subsurface clade 1, which predominates in a diversity of Fe(III)-reducing subsurface environments. Most of the gscA sequences recovered from groundwater genomic DNA clustered in a tight phylogenetic group closely related to strain M18. GscA was most abundant in groundwater samples in which Geobacter sp. predominated. Expression of gscA in a strain of Geobacter sulfurreducens that lacked the gene for the c-type cytochrome OmcS, thought to facilitate electron transfer from conductive pili to Fe(III) oxide, restored the capacity for Fe(III) oxide reduction. Atomic force microscopy provided evidence that GscA was associated with the pili. These results demonstrate that a c-type cytochrome with an apparent function similar to that of OmcS is abundant when Geobacter sp. are abundant in the subsurface, providing insight into the mechanisms for the growth of subsurface Geobacter sp. on Fe(III) oxide and suggesting an approach for functional analysis of other Geobacter proteins found in the subsurface. PMID:26140532

  9. MICROBIAL TRANSFORMATIONS OF RADIONUCLIDES AND ENVIRONMENTAL RESTORATION THROUGH BIOREMEDIATION.

    Energy Technology Data Exchange (ETDEWEB)

    FRANCIS, A.J.

    2006-09-29

    Treatment of waste streams containing radionuclides, the remediation of contaminated materials, soils, and water, and the safe and economical disposal of radionuclides and toxic metals containing wastes is a major concern. Radionuclides may exist in various oxidation states and may be present as oxide, coprecipitates, inorganic, and organic complexes depending on the process and waste stream. Unlike organic contaminants, the metals cannot be destroyed, but must either be converted to a stable form or removed. Microorganisms present in the natural environment play a major role in the mobilization and immobilization of radionuclides and toxic metals by direct enzymatic or indirect non-enzymatic actions and could affect the chemical nature of the radionuclides by altering the speciation, solubility and sorption properties and thus could increase or decrease the concentrations of radionuclides in solution. Fundamental understanding of the mechanisms of microbiological transformations of various chemical forms of uranium present in wastes and contaminated soils and water has led to the development of novel bioremediation processes. One process uses anaerobic bacteria to stabilize the radionuclides by reductive precipitation from higher to lower oxidation state with a concurrent reduction in volume due to the dissolution and removal of nontoxic elements from the waste matrix. In an another process, uranium and other toxic metals are removed from contaminated surfaces, soils, and wastes by extracting with the chelating agent citric acid. Uranium is recovered from the citric acid extract after biodegradation followed by photodegradation in a concentrated form as UO{sub 3} {center_dot} 2H{sub 2}O for recycling or appropriate disposal. These processes use all naturally occurring materials, common soil bacteria, naturally occurring organic compound citric acid and sunlight.

  10. Optimization of a Hydrocarbon Bioremediation System at Laboratory Scale

    Directory of Open Access Journals (Sweden)

    Acuña A.J.

    2012-01-01

    Full Text Available The aim of this study was to optimize the parameters of moisture, temperature and ratio of nutrients to estimate the possibility of applying the technique of bioremediation in a soil contaminated with hydrocarbons. For this, an initial characterization of contaminated soil was made according to their physical and chemical characteristics and the number of heterotrophic and hydrocarbon degraders bacteria. Also the contaminant concentration by gravimetric method and by gas chromatography was studied. To optimize moisture and temperature, microcosms with moisture of 3%, 10%, 15% and 20% and temperatures of 5°C, 15°C, 28°C and 37°C were used. The monitoring of the mineralization of hydrocarbons was performed by measuring the CO2 produced. To optimize the ratio of nutrients, different microcosms were designed and were monitored by oxygen consumption and by determination of hydrocarbons by gas chromatography. The C:N:P relationships studied were 100:20:2, 100:10:1, 100:5:0,5 and 100:1:0,1. The results indicate that the mineralization of hydrocarbons was optimal for moisture of 10% to 20% and temperatures of 25°C to 37°C with CO2 production values of 3000-4500 mgCO2 kg-1. The optimal C:N:P ratio was 100:1:0,1 in which the highest oxygen consumption was and the elimination of 83% of total hydrocarbons determined by gas chromatography with 78% and 89% of n-alkanes and polyaromatic hydrocarbons elimination, respectively.

  11. Bioremediation potential of microorganisms derived from petroleum reservoirs

    International Nuclear Information System (INIS)

    Highlights: • Metagenomic clones could degrade saturated hydrocarbons up to 47% in petroleum. • Metagenomic clones consumed more than 90% of some aromatic portion after 21 days. • Isolated strains could degrade n-alkanes with rates up to 99% after 21 days. • Bacterial strains and metagenomic clones showed high petroleum degradation potential. - Abstract: Bacterial strains and metagenomic clones, both obtained from petroleum reservoirs, were evaluated for petroleum degradation abilities either individually or in pools using seawater microcosms for 21 days. Gas Chromatography–Flame Ionization Detector (GC–FID) and Gas Chromatography-Mass Spectrometry (GC–MS) analyses were carried out to evaluate crude oil degradation. The results showed that metagenomic clones 1A and 2B were able to biodegrade n-alkanes (C14 to C33) and isoprenoids (phytane and pristane), with rates ranging from 31% to 47%, respectively. The bacteria Dietzia maris CBMAI 705 and Micrococcus sp. CBMAI 636 showed higher rates reaching 99% after 21 days. The metagenomic clone pool biodegraded these compounds at rates ranging from 11% to 45%. Regarding aromatic compound biodegradation, metagenomic clones 2B and 10A were able to biodegrade up to 94% of phenanthrene and methylphenanthrenes (3-MP, 2-MP, 9-MP and 1-MP) with rates ranging from 55% to 70% after 21 days, while the bacteria Dietzia maris CBMAI 705 and Micrococcus sp. CBMAI 636 were able to biodegrade 63% and up to 99% of phenanthrene, respectively, and methylphenanthrenes (3-MP, 2-MP, 9-MP and 1-MP) with rates ranging from 23% to 99% after 21 days. In this work, isolated strains as well as metagenomic clones were capable of degrading several petroleum compounds, revealing an innovative strategy and a great potential for further biotechnological and bioremediation applications

  12. Effectiveness of bioremediation of crude oil contaminated subantarctic intertidal sediment: The microbial response

    OpenAIRE

    Delille, D.; B. Delille; Pelletier, E.

    2002-01-01

    A field study was initiated in February 1996 in a remote sandy beach of The Grande Terre (Kerguelen Archipelago, 69°42' E, 49°19' S) with the objective of determining the long-term effects of some bioremediation agents on the biodegradation rate and the toxicity of oil residues under severe subantarctic conditions. A series of 10 experimental plots were settled firmly into sediment. Each plot received 2L of Arabian light crude oil and some of them were treated with bioremediation agents: slow...

  13. Immobilized Native Bacteria as a Tool for Bioremediation of Soils and Waters: Implementation and Modeling

    Directory of Open Access Journals (Sweden)

    C. Lobo

    2002-01-01

    Full Text Available Based on 3,4-dihydroxyphenylacetate (3,4-DHPA dioxygenase amino acid sequence and DNA sequence data for homologous genes, two different oligonucleotides were designed. These were assayed to detect 3,4-DHPA related aromatic compound—degrading bacteria in soil samples by using the FISH method. Also, amplification by PCR using a set of ERIC primers was assayed for the detection of Pseudomonas GCH1 strain, which used in the soil bioremediation process. A model was developed to understand and predict the behavior of bacteria and pollutants in a bioremediation system, taking into account fluid dynamics, molecular/cellular scale processes, and biofilm formation.

  14. Bioremediation of a Large Chlorinated Solvent Plume, Dover AFB, DE

    Energy Technology Data Exchange (ETDEWEB)

    Bloom, Aleisa C [ORNL

    2015-01-01

    Bioremediation of a Large Chlorinated Solvent Plume, Dover AFB, DE Aleisa Bloom, (Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA) Robert Lyon (bob.lyon@aecom.com), Laurie Stenberg, and Holly Brown (AECOM, Germantown, Maryland, USA) ABSTRACT: Past disposal practices at Dover Air Force Base (AFB), Delaware, created a large solvent plume called Area 6 (about 1 mile long, 2,000 feet wide, and 345 acres). The main contaminants are PCE, TCE, and their degradation products. The remedy is in-situ accelerated anaerobic bioremediation (AAB). AAB started in 2006 and is focusing on source areas and downgradient plume cores. Direct-push injections occurred in source areas where contamination is typically between 5 and 20 feet below ground surface. Lower concentration dissolved-phased contamination is present downgradient at 35 and 50 feet below ground surface. Here, permanent injection/extraction wells installed in transects perpendicular to the flow of groundwater are used to apply AAB. The AAB substrate is a mix of sodium lactate, emulsified vegetable oil, and nutrients. After eight years, dissolved contaminant mass within the main 80-acre treatment area has been reduced by over 98 percent. This successful application of AAB has stopped the flux of contaminants to the more distal portions of the plume. While more time is needed for effects to be seen in the distal plume, AAB injections will soon cease, and the remedy will transition to natural attenuation. INTRODUCTION Oak Ridge National Laboratory Environmental Science Division (ORNL) and AECOM (formerly URS Corporation) have successfully implemented in situ accelerated anaerobic bioremediation (AAB) to remediate chlorinated solvent contamination in a large, multi-sourced groundwater plume at Dover Air Force Base (AFB). AAB has resulted in significant reductions of dissolved phase chlorinated solvent concentrations. This plume, called Area 6, was originally over 1 mile in length and over 2,000 feet wide (Figure 1

  15. Dynamic similarity in erosional processes

    Science.gov (United States)

    Scheidegger, A.E.

    1963-01-01

    A study is made of the dynamic similarity conditions obtaining in a variety of erosional processes. The pertinent equations for each type of process are written in dimensionless form; the similarity conditions can then easily be deduced. The processes treated are: raindrop action, slope evolution and river erosion. ?? 1963 Istituto Geofisico Italiano.

  16. Personalized recommendation with corrected similarity

    International Nuclear Information System (INIS)

    Personalized recommendation has attracted a surge of interdisciplinary research. Especially, similarity-based methods in applications of real recommendation systems have achieved great success. However, the computations of similarities are overestimated or underestimated, in particular because of the defective strategy of unidirectional similarity estimation. In this paper, we solve this drawback by leveraging mutual correction of forward and backward similarity estimations, and propose a new personalized recommendation index, i.e., corrected similarity based inference (CSI). Through extensive experiments on four benchmark datasets, the results show a greater improvement of CSI in comparison with these mainstream baselines. And a detailed analysis is presented to unveil and understand the origin of such difference between CSI and mainstream indices. (paper)

  17. Similarity of samples and trimming

    CERN Document Server

    Álvarez-Esteban, Pedro C; Cuesta-Albertos, Juan A; Matrán, Carlos; 10.3150/11-BEJ351

    2012-01-01

    We say that two probabilities are similar at level $\\alpha$ if they are contaminated versions (up to an $\\alpha$ fraction) of the same common probability. We show how this model is related to minimal distances between sets of trimmed probabilities. Empirical versions turn out to present an overfitting effect in the sense that trimming beyond the similarity level results in trimmed samples that are closer than expected to each other. We show how this can be combined with a bootstrap approach to assess similarity from two data samples.

  18. Explaining spatial homogamy: compositional, spatial and regional cultural determinants of regional patterns of spatial homogamy in the Netherlands

    OpenAIRE

    Haandrikman, K.; Wissen, L.J.G.; Harmsen, C.N.

    2011-01-01

    Spatial homogamy, or sharing a similarity in geographical origin, is an under-researched dimension in homogamy studies. In the Netherlands, people tend to choose spatially homogamous partners. Moreover, there is considerable regional variation in spatial homogamy, even when residential location and population density are controlled for. This study aims to explain the regional variation in spatial homogamy by means of a spatial regression. Three sets of explanations are taken into account: com...

  19. Justice… spatiale !

    OpenAIRE

    Gervais-Lambony, Philippe; Dufaux, Frédéric

    2009-01-01

    International audience The notion of spatial justice was developed by Anglo-Saxon radical geographyin the 1970’s. Today it is often used in different contexts, mostly within thefield of urban studies. The central idea in this paper is to demonstrate thata revisited form of the concept of « spatial justice » may be used to promoteinteraction between the very diverse contemporary approaches of geography atevery scale. The theoretical background of political philosophy is presented first,we t...

  20. Self-similar aftershock rates

    CERN Document Server

    Davidsen, Jörn

    2016-01-01

    In many important systems exhibiting crackling noise --- intermittent avalanche-like relaxation response with power-law and, thus, self-similar distributed event sizes --- the "laws" for the rate of activity after large events are not consistent with the overall self-similar behavior expected on theoretical grounds. This is in particular true for the case of seismicity and a satisfying solution to this paradox has remained outstanding. Here, we propose a generalized description of the aftershock rates which is both self-similar and consistent with all other known self-similar features. Comparing our theoretical predictions with high resolution earthquake data from Southern California we find excellent agreement, providing in particular clear evidence for a unified description of aftershocks and foreshocks. This may offer an improved way of time-dependent seismic hazard assessment and earthquake forecasting.

  1. Self-similar aftershock rates

    Science.gov (United States)

    Davidsen, Jörn; Baiesi, Marco

    2016-08-01

    In many important systems exhibiting crackling noise—an intermittent avalanchelike relaxation response with power-law and, thus, self-similar distributed event sizes—the "laws" for the rate of activity after large events are not consistent with the overall self-similar behavior expected on theoretical grounds. This is particularly true for the case of seismicity, and a satisfying solution to this paradox has remained outstanding. Here, we propose a generalized description of the aftershock rates which is both self-similar and consistent with all other known self-similar features. Comparing our theoretical predictions with high-resolution earthquake data from Southern California we find excellent agreement, providing particularly clear evidence for a unified description of aftershocks and foreshocks. This may offer an improved framework for time-dependent seismic hazard assessment and earthquake forecasting.

  2. Community Detection by Neighborhood Similarity

    Institute of Scientific and Technical Information of China (English)

    LIU Xu; XIE Zheng; YI Dong-Yun

    2012-01-01

    Detection of the community structure in a network is important for understanding the structure and dynamics of the network.By exploring the neighborhood of vertices,a local similarity metric is proposed,which can be quickly computed.The resulting similarity matrix retains the same support as the adjacency matrix.Based on local similarity,an agglomerative hierarchical clustering algorithm is proposed for community detection.The algorithm is implemented by an efficient max-heap data structure and runs in nearly linear time,thus is capable of dealing with large sparse networks with tens of thousands of nodes.Experiments on synthesized and real-world networks demonstrate that our method is efficient to detect community structures,and the proposed metric is the most suitable one among all the tested similarity indices.%Detection of the community structure in a network is important for understanding the structure and dynamics of the network. By exploring the neighborhood of vertices, a local similarity metric is proposed, which can be quickly computed. The resulting similarity matrix retains the same support as the adjacency matrix. Based on local similarity, an agglomerative hierarchical clustering algorithm is proposed for community detection. The algorithm is implemented by an efficient max-heap data structure and runs in nearly linear time, thus is capable of dealing with large sparse networks with tens of thousands of nodes. Experiments on synthesized and real-world networks demonstrate that our method is efficient to detect community structures, and the proposed metric is the most suitable one among all the tested similarity indices.

  3. SELF-SIMILAR TRAFFIC GENERATOR

    OpenAIRE

    Linawati Linawati; I Made Suartika

    2009-01-01

    Network traffic generator can be produced using OPNET. OPNET generates the traffic as explicit traffic or background traffic. This paper demonstrates generating traffic in OPNET 7.0 as background traffic. The traffi generator that was simulated is self-similar traffic with different Hurst parameter. The simulation results proved that OPNET with background traffic function can be as a qualified self-similar traffic generator. These results can help in investigating and analysing network perfor...

  4. Similarity measures for protein ensembles

    DEFF Research Database (Denmark)

    Lindorff-Larsen, Kresten; Ferkinghoff-Borg, Jesper

    2009-01-01

    Analyses of similarities and changes in protein conformation can provide important information regarding protein function and evolution. Many scores, including the commonly used root mean square deviation, have therefore been developed to quantify the similarities of different protein conformations...... a synthetic example from molecular dynamics simulations. We then apply the algorithms to revisit the problem of ensemble averaging during structure determination of proteins, and find that an ensemble refinement method is able to recover the correct distribution of conformations better than standard single...

  5. Self-Similar Isentropic Implosions

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, M.; Amable, L.

    1980-07-01

    The self-similar compression of an isentropic spherical gas pellet Is analyzed for large values of the ratio of the final to initial densities. An asymptotic analysis provides the solution corresponding to a prescribed value of the final density when it is high. In addition an approximate solution is given when the specific heat ratio is not constant. The time evolution of the pressure on the outer surface leading to the self-similar solutions, is calculated for large density ratios. (Author)

  6. Molecular similarity of MDR inhibitors

    OpenAIRE

    Simon Gibbons; Mire Zloh

    2004-01-01

    Abstract: The molecular similarity of multidrug resistance (MDR) inhibitors was evaluated using the point centred atom charge approach in an attempt to find some common features of structurally unrelated inhibitors. A series of inhibitors of bacterial MDR were studied and there is a high similarity between these in terms of their shape, presence and orientation of aromatic ring moieties. A comparison of the lipophilic properties of these molecules has also been conducted suggesting that this ...

  7. Representation is representation of similarities.

    Science.gov (United States)

    Edelman, S

    1998-08-01

    Advanced perceptual systems are faced with the problem of securing a principled (ideally, veridical) relationship between the world and its internal representation. I propose a unified approach to visual representation, addressing the need for superordinate and basic-level categorization and for the identification of specific instances of familiar categories. According to the proposed theory, a shape is represented internally by the responses of a small number of tuned modules, each broadly selective for some reference shape, whose similarity to the stimulus it measures. This amounts to embedding the stimulus in a low-dimensional proximal shape space spanned by the outputs of the active modules. This shape space supports representations of distal shape similarities that are veridical as Shepard's (1968) second-order isomorphisms (i.e., correspondence between distal and proximal similarities among shapes, rather than between distal shapes and their proximal representations). Representation in terms of similarities to reference shapes supports processing (e.g., discrimination) of shapes that are radically different from the reference ones, without the need for the computationally problematic decomposition into parts required by other theories. Furthermore, a general expression for similarity between two stimuli, based on comparisons to reference shapes, can be used to derive models of perceived similarity ranging from continuous, symmetric, and hierarchical ones, as in multidimensional scaling (Shepard 1980), to discrete and nonhierarchical ones, as in the general contrast models (Shepard & Arabie 1979; Tversky 1977). PMID:10097019

  8. Walking softly : using bioremediation to reclaim sites leaves a smaller footprint than traditional dig-and-dump technologies

    International Nuclear Information System (INIS)

    Recent developments in the bioremediation industry in Alberta were outlined. The market for bioremediation services in the United States alone is estimated to hit $1 billion by 2010 and has become a staple of the U.S. Environmental Protection Agency's emergency management practices in the event of an oil spill. Alberta Environment has recently updated its policies and guidance documents on contaminated sites management, and is planning a manual that will include best bioremediation practices. Advances in the science and technology of bioremediation and a rise in environmental awareness have contributed to the sector's growth in recent years. In the past, oil companies in Alberta typically reclaimed sites by digging up contaminated soil and trucking it to landfills. Recent techniques developed by industry and bioremediation experts now mean that soil profiles can remain undisturbed, and biological treatment amendments are often introduced into the fractures to destroy contaminants where they lie. The National Research Council's Biotechnology Research Institute (NRC-BRI) is now conducting research to identify and profile unknown micro-organisms to improve conditions for the breakdown of toxins. Bioremediation techniques are also being used in urban redevelopment. It was concluded that while the environmental industry is regulatory-driven, many oil and mining companies are deciding to invest in remediation instead of waiting until a later date. A list of new bioremediation partnerships with industry, government and municipalities was also provided. 2 figs

  9. Literature review and assessment of various approaches to bioremediation of oil and associated hydrocarbons in soil and groundwater

    International Nuclear Information System (INIS)

    A study was conducted of available techniques for the biological treatment of oil and associated hydrocarbon contamination in soil and groundwater. The study involved a detailed literature search and review, as well as discussions with the users and developers of a number of the bioremediation techniques assessed. The result is a compendium of selected state-of-the-art bioremediation technologies which can serve to guide the selection process for treatment technology for a particular site subject to remediation. Background is provided on the various classes of sites on which petroleum-related contamination could occur, and the nature of contaminants typical of such sites. The mechanisms of hydrocarbon biodegradation are outlined along with various approaches to bioremediation such as in-situ, on-site, bioreactors, landfarming, composting, and physical/chemical treatments. Field trials required to characterize the site and provide an indication of the suitability of bioremediation and the most appropriate bioremediation approach are described. Commercially available bioremediation technologies are briefly discussed. A number of the bioremedial techniques reviewed are compared to more conventional treatment processes in terms of such criteria as operating cost, effectiveness, advantages, risks, applicability, equipment and manpower requirements, and considerations regarding usage in Canadian conditions. 15 figs., 17 tabs

  10. Multiscale Modeling for Biomass Growth Associated with Bioremediation and Its Impact on Permeability Change and Distribution of Contaminants

    Science.gov (United States)

    Oka, G. K.; Pinder, G.

    2009-12-01

    Bioremediation involves using bacteria present in the soil or injected into the soil to degrade contaminants dissolved in groundwater. The degrading bacteria grow attached to the soil particles using the contaminants as substrate for growth. In the process, the pore spaces between soil particles get partially or totally blocked. This blocking, called bioclogging, affects an important parameter, the permeability of soil, which governs the distribution of contaminants in groundwater. The distribution of contaminants in turn affects the growth of bacteria through its changed availability pattern. We attempt to model the complex relationship between the growth of bacteria and biodegradation of the contaminants by coupling a 'Cellular Automata' (CA) model for biomass growth with a multiphase transport model for contaminants in groundwater. The growth in biomass of bacteria at the microscopic spatial scale is translated into a change in permeability at the macroscopic scale by using averaging techniques on CA grids regarding them as 'Representative Elementary Volume' (REV) elements. The results of simulation are presented and compared with a laboratory column experiment.

  11. Genome Sequence of Klebsiella quasipneumoniae subsp. similipneumoniae MB373, an Effective Bioremediator

    Science.gov (United States)

    Aslam, Fozia; Thomas, Torsten

    2016-01-01

    Klebsiella quasipneumoniae subsp. similipneumoniae MB373 was isolated from effluent of the Hattar Industrial Estate, Haripur, Pakistan. K. quasipneumoniae subsp. similipneumoniae has few cultivated/characterized members so far. Whole-genome sequencing revealed its potential for metal and toxin resistance, which further elucidated various enzymatic processes for the degradation of xenobiotics, illuminating its bioremediation applications. PMID:27688323

  12. Stable isotope probing in the metagenomics era: a bridge towards improved bioremediation

    OpenAIRE

    Uhlik, Ondrej; Leewis, Mary-Cathrine; Strejcek, Michal; Musilova, Lucie; Mackova, Martina; Leigh, Mary Beth; Macek, Tomas

    2012-01-01

    Microbial biodegradation and biotransformation reactions are essential to most bioremediation processes, yet the specific organisms, genes, and mechanisms involved are often not well understood. Stable isotope probing (SIP) enables researchers to directly link microbial metabolic capability to phylogenetic and metagenomic information within a community context by tracking isotopically labeled substances into phylogenetically and functionally informative biomarkers. SIP is thus applicable as a...

  13. Characterization of bacterial consortia for its use in bioremediation of gas-oil contaminated antarctic soils

    Energy Technology Data Exchange (ETDEWEB)

    Ruberto, L.; Vazquez, S.; Mestre, C.; Nogales, B.; Christie-Oleza, J.; Bosch, R.; Mac Cormack, W. P.

    2009-07-01

    Success of bio augmentation of chronically-contaminated soils is controversial, mainly because the inocula are frequently unable to establish in the matrix under bioremediation. In Antarctica, the environmental conditions and the restriction for the introduction of non-autochthonous organisms (imposed by the Antarctic Treaty) prevent inoculation with foreign bacteria. (Author)

  14. High bacterial biodiversity increases degradation performance of hydrocarbons during bioremediation of contaminated harbor marine sediments

    International Nuclear Information System (INIS)

    We investigated changes of bacterial abundance and biodiversity during bioremediation experiments carried out on oxic and anoxic marine harbor sediments contaminated with hydrocarbons. Oxic sediments, supplied with inorganic nutrients, were incubated in aerobic conditions at 20 °C and 35 °C for 30 days, whereas anoxic sediments, amended with organic substrates, were incubated in anaerobic conditions at the same temperatures for 60 days. Results reported here indicate that temperature exerted the main effect on bacterial abundance, diversity and assemblage composition. At higher temperature bacterial diversity and evenness increased significantly in aerobic conditions, whilst decreased in anaerobic conditions. In both aerobic and anaerobic conditions, biodegradation efficiencies of hydrocarbons were significantly and positively related with bacterial richness and evenness. Overall results presented here suggest that bioremediation strategies, which can sustain high levels of bacterial diversity rather than the selection of specific taxa, may significantly increase the efficiency of hydrocarbon degradation in contaminated marine sediments. - Highlights: ► Bioremediation performance was investigated on hydrocarbon contaminated sediments. ► Major changes in bacterial diversity and assemblage composition were observed. ► Temperature exerted the major effect on bacterial assemblages. ► High bacterial diversity increased significantly biodegradation performance. This should be considered for sediment remediation by bio-treatments. - Bioremediation strategies which can sustain high levels of bacterial diversity may significantly increase the biodegradation of hydrocarbons in contaminated marine sediments.

  15. Bioremediation of hydrocarbon-contaminated soils: are treatability and ecotoxicity endpoints related?

    International Nuclear Information System (INIS)

    To determine if there is a relationship between biotreatability and ecotoxicity endpoints in a wide range of hydrocarbon-contaminated soils, including medium and heavy crude oil-contaminated flare pit wastes and lubrication oil contaminated soil, research was conducted. Each test material was analyzed for pH, water repellency, electrical conductivity, available N and P, total extractable hydrocarbons, oil and grease, and toxicity to seedling emergence, root elongation in barley, lettuce and canola, earthworm survival and luminescent bacteria (Microtox), prior to, and following three months of bioremediation in the laboratory. By monitoring soil respiration, progress of the bioremediation process and determination of a treatment endpoint were assessed. The time required to attain a treatment endpoint under laboratory conditions can range from 30 days to 100 days depending on the concentration of hydrocarbons and degree of weathering. Most flare pits are biotreatable, averaging a loss of 25-30% of hydrocarbons during bioremediation. Once a treatment endpoint is achieved, residual hydrocarbons contents almost always exceeds Alberta Tier I criteria for mineral oil and grease. As a result of bioremediation treatments, hydrophobicity is often reduced from severe to low. Many flare pit materials are still moderately to extremely toxic after reaching a treatment endpoint. (Abstract only)

  16. MICROBIAL ANALYSIS OF MTBE, BTEX BIOREMEDIATION: BIONETS CONTAINING PM1, SOS, ISOLITE.

    Science.gov (United States)

    MTBE and BTEX (benzene, toluene, ethylbenzene, and xylene) are major problems of many sites in the United States. The objective of this study was to determine if biologically active in-situ BioNets could bioremediation MTBE and BTEX contaminated groundwater. Seven BioNets were ...

  17. MICROBIAL ANALYSIS OF MTBE, BTEX BIOREMEDIATION: BIONETS(TM) CONTAINING PM1, SOS, ISOLITE (R)

    Science.gov (United States)

    MTBE and BTEX (benzene, toluene, ethylbenzene, and xylene) are major problems of many sites in the United States. The objective of this study was to determine if biologically active in-situ BioNets could bioremediation MTBE and BTEX contaminated groundwater. Seven BioNets were ...

  18. BTEX AND MTBE BIOREMEDIATION: BIONETS™ CONTAINING SOS, PM1 AND ISOLITE®

    Science.gov (United States)

    MTBE and BTEX (benzene, toluene, ethylbenzene, and xylenes) are major problems of many sites in the United States. The objective of this study was to determine if biologically active in situ BioNets could bioremediate MTBE and BTEX contaminated groundwater. Seven BioNets w...

  19. MICROBIAL ANALYSIS OF MTBE, BTEX BIOREMEDIATION: BIONETS CONTAINING PM1, SOS, ISOLITE�

    Science.gov (United States)

    MTBE and BTEX (benzene, toluene, ethylbenzene, and xylene) are major problems of many sites in the United States. The objective of this study was to determine if biologically active in-situ BioNets could bioremediate MTBE and BTEX contaminated groundwater. Seven BioNets were plac...

  20. Natural and Accelerated Bioremediation Research (NABIR) Field Research Center (FRC) Management Plan

    Energy Technology Data Exchange (ETDEWEB)

    Watson, D.B.

    2002-02-28

    The Environmental Sciences Division at Oak Ridge National Laboratory has established a Field Research Center (FRC) to support the Natural and Accelerated Bioremediation Research (NABIR) Program on the U.S. Department of Energy (DOE) Oak Ridge Reservation in Oak Ridge, Tennessee for the DOE Headquarters Office of Biological and Environmental Research within the Office of Science.

  1. Bioremediation strategies for removal of residual atrazine in the boreal groundwater zone.

    Science.gov (United States)

    Nousiainen, Aura O; Björklöf, Katarina; Sagarkar, Sneha; Nielsen, Jeppe Lund; Kapley, Atya; Jørgensen, Kirsten S

    2015-12-01

    Strategies for bioremediation of atrazine, a pesticide commonly polluting groundwater in low concentrations, were studied in two boreal nonagricultural soils. Atrazine was not mineralized in soil without bioremediation treatments. In biostimulation treatment with molasses, up to 52% of atrazine was mineralized at 10 °C, even though the degradation gene copy numbers did not increase. Incubations with radioactively labeled atrazine followed by microautoradiographic analysis revealed that bioremediation strategies increased the relative proportion of active degraders from 0.3 up to 1.9% of the total bacterial count. These results indicate that atrazine degradation might not solely be facilitated by atzA/trzN-atzB genes. In combined biostimulation treatment using citrate or molasses and augmentation with Pseudomonas citronellolis ADP or Arthrobacter aurescens strain TC1, up to 76% of atrazine was mineralized at 30 °C, and the atrazine degradation gene numbers increased up to 10(7) copies g(-1) soil. Clone libraries from passive samplers in groundwater monitoring wells revealed the presence of phylogenetic groups formerly shown to include atrazine degraders, and the presence of atrazine degradation genes atzA and atzB. These results show that the mineralization of low concentrations of atrazine in the groundwater zone at low temperatures is possible by bioremediation treatments.

  2. Colloidal properties of nanoparticular biogenic selenium govern environmental fate and bioremediation effectiveness

    NARCIS (Netherlands)

    Buchs, B.; Evangelou, M.H.W.; Winkel, L.; Lenz, M.

    2013-01-01

    Microbial selenium (Se) bioremediation is based on conversion of water soluble, toxic Se oxyanions to water insoluble, elemental Se. Formed biogenic elemental Se is of nanometer size, hampering straightforward separation from the aqueous phase. This study represents the first systematic investigatio

  3. Microorganisms in heavy metal bioremediation: strategies for applying microbial-community engineering to remediate soils

    Directory of Open Access Journals (Sweden)

    Jennifer L. Wood

    2016-06-01

    Full Text Available The remediation of heavy-metal-contaminated soils is essential as heavy metals persist and do not degrade in the environment. Remediating heavy-metal-contaminated soils requires metals to be mobilized for extraction whilst, at the same time, employing strategies to avoid mobilized metals leaching into ground-water or aquatic systems. Phytoextraction is a bioremediation strategy that extracts heavy metals from soils by sequestration in plant tissues and is currently the predominant bioremediation strategy investigated for remediating heavy-metal-contaminated soils. Although the efficiency of phytoextraction remains a limiting feature of the technology, there are numerous reports that soil microorganisms can improve rates of heavy metal extraction.This review highlights the unique challenges faced when remediating heavy-metal-contaminated soils as compared to static aquatic systems and suggests new strategies for using microorganisms to improve phytoextraction. We compare how microorganisms are used in soil bioremediation (i.e. phytoextraction and water bioremediation processes, discussing how the engineering of microbial communities, used in water remediation, could be applied to phytoextraction. We briefly outline possible approaches for the engineering of soil communities to improve phytoextraction either by mobilizing metals in the rhizosphere of the plant or by promoting plant growth to increase the root-surface area available for uptake of heavy metals. We highlight the technological advances that make this research direction possible and how these technologies could be employed in future research.

  4. Ripening of PAH and TPH polluted sediments : determination and quantification of bioremediation parameters

    NARCIS (Netherlands)

    Vermeulen, J.

    2007-01-01

    In this study, bioremediation parameters were determined and quantified for different clayey dredged sediments. The research described in this thesis increased the insight into the individual processes of physical ripening, biochemical ripening – including PAH and TPH degradation – that result from

  5. Effect of alternating bioremediation and electrokinetics on the remediation of n-hexadecane-contaminated soil

    Science.gov (United States)

    Wang, Sa; Guo, Shuhai; Li, Fengmei; Yang, Xuelian; Teng, Fei; Wang, Jianing

    2016-04-01

    This study demonstrated the highly efficient degradation of n-hexadecane in soil, realized by alternating bioremediation and electrokinetic technologies. Using an alternating technology instead of simultaneous application prevented competition between the processes that would lower their efficiency. For the consumption of the soil dissolved organic matter (DOM) necessary for bioremediation by electrokinetics, bioremediation was performed first. Because of the utilization and loss of the DOM and water-soluble ions by the microbial and electrokinetic processes, respectively, both of them were supplemented to provide a basic carbon resource, maintain a high electrical conductivity and produce a uniform distribution of ions. The moisture and bacteria were also supplemented. The optimal DOM supplement (20.5 mg·kg-1 glucose; 80-90% of the total natural DOM content in the soil) was calculated to avoid competitive effects (between the DOM and n-hexadecane) and to prevent nutritional deficiency. The replenishment of the water-soluble ions maintained their content equal to their initial concentrations. The degradation rate of n-hexadecane was only 167.0 mg·kg-1·d-1 (1.9%, w/w) for the first 9 days in the treatments with bioremediation or electrokinetics alone, but this rate was realized throughout the whole process when the two technologies were alternated, with a degradation of 78.5% ± 2.0% for the n-hexadecane after 45 days of treatment.

  6. Characterization of bacterial consortia for its use in bioremediation of gas-oil contaminated antarctic soils

    International Nuclear Information System (INIS)

    Success of bio augmentation of chronically-contaminated soils is controversial, mainly because the inocula are frequently unable to establish in the matrix under bioremediation. In Antarctica, the environmental conditions and the restriction for the introduction of non-autochthonous organisms (imposed by the Antarctic Treaty) prevent inoculation with foreign bacteria. (Author)

  7. Recovery of microbial diversity and activity during bioremediation following chemical oxidation of diesel contaminated soils

    NARCIS (Netherlands)

    Sutton, N.B.; Langenhoff, A.A.M.; Hidalgo Lasso, D.; Zaan, van der B.M.; Gaans, van P.; Maphosa, F.; Smidt, H.; Grotenhuis, J.T.C.; Rijnaarts, H.H.M.

    2014-01-01

    To improve the coupling of in situ chemical oxidation and in situ bioremediation, a systematic analysis was performed of the effect of chemical oxidation with Fenton's reagent, modified Fenton's reagent, permanganate, or persulfate, on microbial diversity and activity during 8 weeks of incubation in

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

    International Nuclear Information System (INIS)

    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

  9. Bioremediation in marine ecosystems: a computational study combining ecological modelling and flux balance analysis

    Directory of Open Access Journals (Sweden)

    Marianna eTaffi

    2014-09-01

    Full Text Available The pressure to search effective bioremediation methodologies for contaminated ecosystems has led to the large-scale identification of microbial species and metabolic degradation pathways. However, minor attention has been paid to the study of bioremediation in marine food webs and to the definition of integrated strategies for reducing bioaccumulation in species. We propose a novel computational framework for analysing the multiscale effects of bioremediation at the ecosystem level, based on coupling food web bioaccumulation models and metabolic models of degrading bacteria. The combination of techniques from synthetic biology and ecological network analysis allows the specification of arbitrary scenarios of contaminant removal and the evaluation of strategies based on natural or synthetic microbial strains.In this study, we derive a bioaccumulation model of polychlorinated biphenyls (PCBs in the Adriatic food web, and we extend a metabolic reconstruction of Pseudomonas putida KT2440 (iJN746 with the aerobic pathway of PCBs degradation. We assess the effectiveness of different bioremediation scenarios in reducing PCBs concentration in species and we study indices of species centrality to measure their importance in the contaminant diffusion via feeding links.The analysis of the Adriatic sea case study suggests that our framework could represent a practical tool in the design of effective remediation strategies, providing at the same time insights into the ecological role of microbial communities within food webs.

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

    Science.gov (United States)

    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...

  11. SITE TECHNOLOGY CAPSULE: J.R. SIMPLOT EX-SITU ANAEROBIC BIOREMEDIATION TECHNOLOGY: TNT

    Science.gov (United States)

    The J.R. Simplot Ex-Situ Bioremediation Technology is designed to degrade nitroaromatic compounds anaerobically, with total destruction of toxic intermediates at the completion of treatment. An evaluation of this technology was conducted under the SITE Program on TNT-contaminated...

  12. Bioremediation strategies for removal of residual atrazine in the boreal groundwater zone.

    Science.gov (United States)

    Nousiainen, Aura O; Björklöf, Katarina; Sagarkar, Sneha; Nielsen, Jeppe Lund; Kapley, Atya; Jørgensen, Kirsten S

    2015-12-01

    Strategies for bioremediation of atrazine, a pesticide commonly polluting groundwater in low concentrations, were studied in two boreal nonagricultural soils. Atrazine was not mineralized in soil without bioremediation treatments. In biostimulation treatment with molasses, up to 52% of atrazine was mineralized at 10 °C, even though the degradation gene copy numbers did not increase. Incubations with radioactively labeled atrazine followed by microautoradiographic analysis revealed that bioremediation strategies increased the relative proportion of active degraders from 0.3 up to 1.9% of the total bacterial count. These results indicate that atrazine degradation might not solely be facilitated by atzA/trzN-atzB genes. In combined biostimulation treatment using citrate or molasses and augmentation with Pseudomonas citronellolis ADP or Arthrobacter aurescens strain TC1, up to 76% of atrazine was mineralized at 30 °C, and the atrazine degradation gene numbers increased up to 10(7) copies g(-1) soil. Clone libraries from passive samplers in groundwater monitoring wells revealed the presence of phylogenetic groups formerly shown to include atrazine degraders, and the presence of atrazine degradation genes atzA and atzB. These results show that the mineralization of low concentrations of atrazine in the groundwater zone at low temperatures is possible by bioremediation treatments. PMID:26239066

  13. Genome Sequence of Klebsiella quasipneumoniae subsp. similipneumoniae MB373, an Effective Bioremediator.

    Science.gov (United States)

    Aslam, Fozia; Yasmin, Azra; Thomas, Torsten

    2016-01-01

    Klebsiella quasipneumoniae subsp. similipneumoniae MB373 was isolated from effluent of the Hattar Industrial Estate, Haripur, Pakistan. K. quasipneumoniae subsp. similipneumoniae has few cultivated/characterized members so far. Whole-genome sequencing revealed its potential for metal and toxin resistance, which further elucidated various enzymatic processes for the degradation of xenobiotics, illuminating its bioremediation applications. PMID:27688323

  14. Mineral transformation and biomass accumulation associated with uranium bioremediation at Rifle, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Li, L.; Steefel, C.I.; Williams, K.H.; Wilkins, M.J.; Hubbard, S.S.

    2009-04-20

    Injection of organic carbon into the subsurface as an electron donor for bioremediation of redox-sensitive contaminants like uranium often leads to mineral transformation and biomass accumulation, both of which can alter the flow field and potentially bioremediation efficacy. This work combines reactive transport modeling with a column experiment and field measurements to understand the biogeochemical processes and to quantify the biomass and mineral transformation/accumulation during a bioremediation experiment at a uranium contaminated site near Rifle, Colorado. We use the reactive transport model CrunchFlow to explicitly simulate microbial community dynamics of iron and sulfate reducers, and their impacts on reaction rates. The column experiment shows clear evidence of mineral precipitation, primarily in the form of calcite and iron monosulfide. At the field scale, reactive transport simulations suggest that the biogeochemical reactions occur mostly close to the injection wells where acetate concentrations are highest, with mineral precipitate and biomass accumulation reaching as high as 1.5% of the pore space. This work shows that reactive transport modeling coupled with field data can be an effective tool for quantitative estimation of mineral transformation and biomass accumulation, thus improving the design of bioremediation strategies.

  15. Feasibility of on-site bioremediation of loam soil contaminated by diesel oil.

    Science.gov (United States)

    Rubin, H; Narkis, N

    2001-09-01

    This study originated from an accidental event of diesel oil contamination in a loam soil area of 7,000 m2. Approximately a volume of 1,300 m3 of diesel oil was released into the environment. Reclamation of the contaminated soil by on-site bioremediation was selected as the most appropriate treatment method. A major concern was associated with the nature of the local loam soil. Loam has a very low hydraulic conductivity and very quickly becomes impermeable after its contact with water. The bioremediation approach incorporated excavation of the contaminated soil, mixing it with an agent, which increased its permeability. Following this preliminary treatment came the construction of bioreactors as a suitable environment of nutrients, moisture, dissolved oxygen, and enriched culture of microorganisms, which enabled breakdown of the diesel oil. This case study indicated that the target of 99% of diesel oil clean up could be achieved by using the technology of on-site bioremediation. The selected treatment method was found to be technologically and economically feasible. However, some improvement in the application of the basic treatment approach might increase the bioremediation efficiency. PMID:11597113

  16. OIL SPILL BIOREMEDIATION: EXPERIENCES, LESSONS AND RESULTS FROM THE EXXON VALDEZ OIL SPILL IN ALASKA

    Science.gov (United States)

    The use of bioremediation as a supplemental cleanup technology in the Exxon Valdez oil spill, in Prince William Sound, Alaska, has proven to be a good example of the problems and successes associated with the practical application of this technology. ield studies conducted by sci...

  17. ROLE OF MICROORGANISMS IN THE BIOREMEDIATION OF THE OIL SPILL INPRINCE WILLIAM SOUND, ALASKA

    Science.gov (United States)

    The U.S. Environmental Protection Agency's Alaskan BioremediationProject was initiated in the aftermath of the March 24, 1989, EXXONVALDEZ oil Spill. he objective of the project was to demonstratean alternative cleanup method for oil-contaminated shorelines basedon enhancing natu...

  18. BIOSTIMULATION CAN SOMETIMES ENHANCE ENVIRONMENTAL CLEANUP - An Editorial Viewpoint on Bioremediation

    Science.gov (United States)

    The Exxon Valdex oil spill, which led to the enactment of the Oil Pollution Act of 1990, gave rise to the largest bioremediation field trial ever attempted. A research sutdy was conducted by EPA in 1989 and 1990 to develop data to support the recommendation to go forward w...

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

    Science.gov (United States)

    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. CONTAMINANT REDISTRIBUTION CAN CONFOUND INTERPRETATION OF OIL-SPILL BIOREMEDIATION STUDIES

    Science.gov (United States)

    The physical redistribution of oil between the inside and outside of experimental plots can affect the results of bioremediation field studies that are conducted on shorelines contaminated by real oil spills. Because untreated oil from the surrounding beach will enter the plot, ...

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

    Science.gov (United States)

    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...

  2. TOXICITY TRENDS DURING AN OIL SPILL BIOREMEDIATION EXPERIMENT ON A SANDY SHORELINE IN DELAWARE, USA

    Science.gov (United States)

    A 13-week, refereed, inter-agency toxicity testing program involving five bioassay methods was used to document the effectiveness of shoreline bioremediation to accelerate toxicity reduction of an oiled sandy shoreline at Fowler Beach, Delaware, USA. The study was part of an inte...

  3. Bioremediation of refinery wastewater using immobilised Burkholderia cepacia and Corynebacterium sp and their transconjugants

    Directory of Open Access Journals (Sweden)

    Abdullahi T. Ajao

    2013-07-01

    Full Text Available When oil spill occurs, it poses serious toxic hazards to all forms of life. Mixed culture of Burkholderia cepacia and Corynebacterium sp isolated from refinery sludge using selective enrichment technique was used for bioremediation of refinery wastewater in a laboratoryscale bioreactor. Physicochemical parameters of both raw and treated water were as determined and compared with Federal Environ - mental Protection Agency (FEPA-limit, Abuja, Nigeria to asses the efficiency of the bioremediation process. Each of the bacterium was screened for the presence of plasmid DNA and for the involvement or otherwise of plasmid in the bioremediation of wastewater. The immobilised cells showed percentage decrease in chemical oxygen demand (97%, biochemical oxygen demand (94%, phenol (98%, total petroleum hydrocarbon (79%, oil and grease (90% of the refinery waste water after 20 days of treatment while their transconjugants showed the multiplicative effect by achieving the same percentage after 10 days of treatment. Therefore, the findings revealed that bioaugmentation of wastewater using transmissible catabolic plasmid will enhance efficiency of the bioremediation by spreading the plasmid among indigenous microbial community either through horizontal gene transfer or transformation.

  4. Intrinsic and enhanced bioremediation in aquifers contaminated with chlorinated and aromatic hydrocarbons in The Netherlands

    NARCIS (Netherlands)

    Rijnaarts, H.H.M.; Aalst-van Leeuwen, M.A. van; Heiningen, E. van; Buyzen, H. van; Sinke, A.; Liere, H.C. van; Harkes, M.; Baartmans, R.; Bosma, T.N.P.; Doddema, H.J.

    1998-01-01

    The feasibility of intrinsic and enhanced bioremediation approaches for 16 contaminated sites in the Netherlands are discussed. At at least five out of 10 chlorinated solvent sites, natural attenuation can be used as one of the tools to prevent further dispersion of the plume. At two sites stimulati

  5. Monitoring Genetic and Metabolic Potential for In-Site Bioremediation: Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Buchanan, M.V.

    2000-07-20

    A number of DOE sites are contaminated with mixtures of dense non-aqueous phase liquids (DNAPLs) such as carbon tetrachloride, chloroform, perchloroethylene, and trichloroethylene. At many of these sites, in situ microbial bioremediation is an attractive strategy for cleanup, since it has the potential to degrade DNAPLs in situ without the need for pump-and-treat or soil removal procedures, and without producing toxic byproducts. A rapid screening method to determine broad range metabolic and genetic potential for contaminant degradation would greatly reduce the cost and time involved in assessment for in situ bioremediation, as well as for monitoring ongoing bioremediation treatment. The objective of this project was the development of mass-spectrometry-based methods to screen for genetic potential for both assessment and monitoring of in situ bioremediation of DNAPLs. These methods were designed to provide more robust and routine methods for DNA-based characterization of the genetic potential of subsurface microbes for degrading pollutants. Specifically, we sought to (1) Develop gene probes that yield information equivalent to conventional probes, but in a smaller size that is more amenable to mass spectrometric detection, (2) Pursue improvements to matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) methodology in order to allow its more general application to gene probe detection, and (3) Increase the throughput of microbial characterization by integrating gene probe preparation, purification, and MALDI-MS analysis.

  6. Practical Bioremediation Course – Laboratory Exercises on Biodegradation of Cationic Surfactant

    Directory of Open Access Journals (Sweden)

    Tomislav Ivankovic

    2015-02-01

    Full Text Available 0 From the perspective of the lab exercises leader and teaching assistant for the Bioremediation course, it was very difficult to design and conduct a set of exercises that would fit the course curriculum and satisfactorily demonstrate bioremediation basics through practical laboratory work. Thus, Bioremediation course students designed the experiment with the help of the teaching assistant; a simulation of possible bioremediation of “Jarun” lake in Zagreb, Croatia, if contaminated with cationic surfactant. The experiment nicely showed how natural bioremediation differs from engineered bioremediation and the levels of success between different types of engineered bioremediation. The laboratory exercises were designed to be interesting and the results perceivable to the students.  Editor's Note:The ASM advocates that students must successfully demonstrate the ability to explain and practice safe laboratory techniques. For more information, read the laboratory safety section of the ASM Curriculum Recommendations: Introductory Course in Microbiology and the Guidelines for Biosafety in Teaching Laboratories, available at www.asm.org. The Editors of JMBE recommend that adopters of the protocols included in this article follow a minimum of Biosafety Level 2 practices. Normal 0 21 false false false HR X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Cambria","serif"; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  7. A review on slurry bioreactors for bioremediation of soils and sediments

    Directory of Open Access Journals (Sweden)

    Poggi-Varaldo Héctor M

    2008-02-01

    Full Text Available Abstract The aim of this work is to present a critical review on slurry bioreactors (SB and their application to bioremediation of soils and sediments polluted with recalcitrant and toxic compounds. The scope of the review encompasses the following subjects: (i process fundamentals of SB and analysis of advantages and disadvantages; (ii the most recent applications of SB to laboratory scale and commercial scale soil bioremediation, with a focus on pesticides, explosives, polynuclear aromatic hydrocarbons, and chlorinated organic pollutants; (iii trends on the use of surfactants to improve availability of contaminants and supplementation with degradable carbon sources to enhance cometabolism of pollutants; (iv recent findings on the utilization of electron acceptors other than oxygen; (v bioaugmentation and advances made on characterization of microbial communities of SB; (vi developments on ecotoxicity assays aimed at evaluating bioremediation efficiency of the process. From this review it can be concluded that SB is an effective ad situ and ex situ technology that can be used for bioremediation of problematic sites, such as those characterized by soils with high contents of clay and organic matter, by pollutants that are recalcitrant, toxic, and display hysteretic behavior, or when bioremediation should be accomplished in short times under the pressure and monitoring of environmental agencies and regulators. SB technology allows for the convenient manipulation and control of several environmental parameters that could lead to enhanced and faster treatment of polluted soils: nutrient N, P and organic carbon source (biostimulation, inocula (bioaugmentation, increased availability of pollutants by use of surfactants or inducing biosurfactant production inside the SB, etc. An interesting emerging area is the use of SB with simultaneous electron acceptors, which has demonstrated its usefulness for the bioremediation of soils polluted with

  8. Diagnosis of In Situ Metabolic State and Rates of Microbial Metabolism During In Situ Uranium Bioremediation with Molecular Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Lovley, Derek R

    2012-11-28

    The goal of these projects was to develop molecule tools to tract the metabolic activity and physiological status of microorganisms during in situ uranium bioremediation. Such information is important in able to design improved bioremediation strategies. As summarized below, the research was highly successful with new strategies developed for estimating in situ rates of metabolism and diagnosing the physiological status of the predominant subsurface microorganisms. This is a first not only for groundwater bioremediation studies, but also for subsurface microbiology in general. The tools and approaches developed in these studies should be applicable to the study of microbial communities in a diversity of soils and sediments.

  9. Similarity measures for face recognition

    CERN Document Server

    Vezzetti, Enrico

    2015-01-01

    Face recognition has several applications, including security, such as (authentication and identification of device users and criminal suspects), and in medicine (corrective surgery and diagnosis). Facial recognition programs rely on algorithms that can compare and compute the similarity between two sets of images. This eBook explains some of the similarity measures used in facial recognition systems in a single volume. Readers will learn about various measures including Minkowski distances, Mahalanobis distances, Hansdorff distances, cosine-based distances, among other methods. The book also summarizes errors that may occur in face recognition methods. Computer scientists "facing face" and looking to select and test different methods of computing similarities will benefit from this book. The book is also useful tool for students undertaking computer vision courses.

  10. Spatial Culture

    DEFF Research Database (Denmark)

    Reeh, Henrik

    2012-01-01

    of Humani-ties, University of Copenhagen, have been exploring urbanity and aesthetics from the viewpoint of their own generation. Some twenty graduates contribute to the present volume which has been entitled Spatial Culture in order to indicate a common denominator of their MA theses from the years 2002......Spatial Culture – A Humanities Perspective Abstract of introductory essay by Henrik Reeh Secured by alliances between socio-political development and cultural practices, a new field of humanistic studies in spatial culture has developed since the 1990s. To focus on links between urban culture...... and modern society is, however, an intellectual practice which has a much longer history. Already in the 1980s, the debate on the modern and the postmodern cited Paris and Los Angeles as spatio-cultural illustrations of these major philosophical concepts. Earlier, in the history of critical studies, the work...

  11. Similarity Measures for Comparing Biclusterings.

    Science.gov (United States)

    Horta, Danilo; Campello, Ricardo J G B

    2014-01-01

    The comparison of ordinary partitions of a set of objects is well established in the clustering literature, which comprehends several studies on the analysis of the properties of similarity measures for comparing partitions. However, similarity measures for clusterings are not readily applicable to biclusterings, since each bicluster is a tuple of two sets (of rows and columns), whereas a cluster is only a single set (of rows). Some biclustering similarity measures have been defined as minor contributions in papers which primarily report on proposals and evaluation of biclustering algorithms or comparative analyses of biclustering algorithms. The consequence is that some desirable properties of such measures have been overlooked in the literature. We review 14 biclustering similarity measures. We define eight desirable properties of a biclustering measure, discuss their importance, and prove which properties each of the reviewed measures has. We show examples drawn and inspired from important studies in which several biclustering measures convey misleading evaluations due to the absence of one or more of the discussed properties. We also advocate the use of a more general comparison approach that is based on the idea of transforming the original problem of comparing biclusterings into an equivalent problem of comparing clustering partitions with overlapping clusters. PMID:26356865

  12. Sparse Similarity-Based Fisherfaces

    DEFF Research Database (Denmark)

    Fagertun, Jens; Gomez, David Delgado; Hansen, Mads Fogtmann;

    2011-01-01

    intensities are used by Sparse Principal Component Analysis and Fisher Linear Discriminant Analysis to assign a one dimensional subspace projection to each person belonging to a reference data set. Experimental results performed in the AR dataset show that Similarity-based Fisherfaces in a sparse version can...

  13. HOW DISSIMILARLY SIMILAR ARE BIOSIMILARS?

    Directory of Open Access Journals (Sweden)

    Ramshankar Vijayalakshmi

    2012-05-01

    Full Text Available Recently Biopharmaceuticals are the new chemotherapeutical agents that are called as “Biosimilars” or “follow on protein products” by the European Medicines Agency (EMA and the American regulatory agencies (Food and Drug Administration respectively. Biosimilars are extremely similar to the reference molecule but not identical, however close their similarities may be. A regulatory framework is therefore in place to assess the application for marketing authorisation of biosimilars. When a biosimilar is similar to the reference biopharmaceutical in terms of safety, quality, and efficacy, it can be registered. It is important to document data from clinical trials with a view of similar safety and efficacy. If the development time for a generic medicine is around 3 years, a biosimilar takes about 6-9 years. Generic medicines need to demonstrate bioequivalence only unlike biosimilars that need to conduct phase I and Phase III clinical trials. In this review, different biosimilars that are already being used successfully in the field on Oncology is discussed. Their similarity, differences and guidelines to be followed before a clinically informed decision to be taken, is discussed. More importantly the regulatory guidelines that are operational in India with a work flow of making a biosimilar with relevant dos and dont’s are discussed. For a large populous country like India, where with improved treatments in all sectors including oncology, our ageing population is increasing. For the health care of this sector, we need more newer, cheaper and effective biosimilars in the market. It becomes therefore important to understand the regulatory guidelines and steps to come up with more biosimilars for the existing population and also more information is mandatory for the practicing clinicians to translate these effectively into clinical practice.

  14. Spatial distribution

    DEFF Research Database (Denmark)

    Borregaard, Michael Krabbe; Hendrichsen, Ditte Katrine; Nachman, Gøsta Støger

    2008-01-01

    , depending on the nature of intraspecific interactions between them: while the individuals of some species repel each other and partition the available area, others form groups of varying size, determined by the fitness of each group member. The spatial distribution pattern of individuals again strongly...

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

    Science.gov (United States)

    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: (...

  16. LITERATURE REVIEW ON THE USE OF COMMERCIAL BIOREMEDIATION AGENTS FOR CLEAN-UP OF OIL-CONTAMINATED ESTUARINE ENVIRONMENTS

    Science.gov (United States)

    The objective of this document is to conduct a comprehensive review of the use of commercial bioremediation products treating oil spills in all environments, Literature assessed includes peer-reviewed articles, company reports, government reports, and reports by cleanup contracto...

  17. Eliciting Public Attitudes Regarding Bioremediation Cleanup Technologies: Lessons Learned from a Consensus Workshop in Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Denise Lach, Principle Investigator; Stephanie Sanford, Co-P.I.

    2003-03-01

    During the summer of 2002, we developed and implemented a ''consensus workshop'' with Idaho citizens to elicit their concerns and issues regarding the use of bioremediation as a cleanup technology for radioactive nuclides and heavy metals at Department of Energy (DOE) sites. The consensus workshop is a derivation of a technology assessment method designed to ensure dialogue between experts and lay people. It has its origins in the United States in the form of ''consensus development conferences'' used by the National Institutes of Health (NIH) to elicit professional knowledge and concerns about new medical treatments. Over the last 25 years, NIH has conducted over 100 consensus development conferences. (Jorgensen 1995). The consensus conference is grounded in the idea that technology assessment and policy needs to be socially negotiated among many different stakeholders and groups rather than narrowly defined by a group of experts. To successfully implement new technology, the public requires access to information that addresses a full complement of issues including understanding the organization proposing the technology. The consensus conference method creates an informed dialogue, making technology understandable to the general public and sets it within perspectives and priorities that may differ radically from those of the expert community. While specific outcomes differ depending on the overall context of a conference, one expected outcome is that citizen panel members develop greater knowledge of the technology during the conference process and, sometimes, the entire panel experiences a change in attitude toward the technology and/or the organization proposing its use (Kluver 1995). The purpose of this research project was to explore the efficacy of the consensus conference model as a way to elicit the input of the general public about bioremediation of radionuclides and heavy metals at Department of Energy sites

  18. Retrieval of similar chess positions

    OpenAIRE

    Ganguly, Debasis; LEVELING, JOHANNES; Jones, Gareth J.F.

    2014-01-01

    We address the problem of retrieving chess game positions similar to a given query position from a collection of archived chess games. We investigate this problem from an information retrieval (IR) perspective. The advantage of our proposed IR-based approach is that it allows using the standard inverted organization of stored chess positions, leading to an ecient retrieval. Moreover, in contrast to retrieving exactly identical board positions, the IR-based approach is able to provide approxim...

  19. Scaling Group Testing Similarity Search

    OpenAIRE

    Iscen, Ahmet; Amsaleg, Laurent; Furon, Teddy

    2016-01-01

    The large dimensionality of modern image feature vectors, up to thousands of dimensions, is challenging the high dimensional indexing techniques. Traditional approaches fail at returning good quality results within a response time that is usable in practice. However, similarity search techniques inspired by the group testing framework have recently been proposed in an attempt to specifically defeat the curse of dimensionality. Yet, group testing does not scale and fails at indexing very large...

  20. Explaining Spatial Homogamy. Compositional, Spatial and Regional Cultural Determinants of Regional Patterns of Spatial Homogamy in the Netherlands

    NARCIS (Netherlands)

    Haandrikman, Karen; van Wissen, Leo J. G.; Harmsen, Carel N.

    2011-01-01

    Spatial homogamy, or sharing a similarity in geographical origin, is an under-researched dimension in homogamy studies. In the Netherlands, people tend to choose spatially homogamous partners. Moreover, there is considerable regional variation in spatial homogamy, even when residential location and

  1. Roget's Thesaurus and Semantic Similarity

    CERN Document Server

    Jarmasz, Mario

    2012-01-01

    We have implemented a system that measures semantic similarity using a computerized 1987 Roget's Thesaurus, and evaluated it by performing a few typical tests. We compare the results of these tests with those produced by WordNet-based similarity measures. One of the benchmarks is Miller and Charles' list of 30 noun pairs to which human judges had assigned similarity measures. We correlate these measures with those computed by several NLP systems. The 30 pairs can be traced back to Rubenstein and Goodenough's 65 pairs, which we have also studied. Our Roget's-based system gets correlations of .878 for the smaller and .818 for the larger list of noun pairs; this is quite close to the .885 that Resnik obtained when he employed humans to replicate the Miller and Charles experiment. We further evaluate our measure by using Roget's and WordNet to answer 80 TOEFL, 50 ESL and 300 Reader's Digest questions: the correct synonym must be selected amongst a group of four words. Our system gets 78.75%, 82.00% and 74.33% of ...

  2. Active browsing using similarity pyramids

    Science.gov (United States)

    Chen, Jau-Yuen; Bouman, Charles A.; Dalton, John C.

    1998-12-01

    In this paper, we describe a new approach to managing large image databases, which we call active browsing. Active browsing integrates relevance feedback into the browsing environment, so that users can modify the database's organization to suit the desired task. Our method is based on a similarity pyramid data structure, which hierarchically organizes the database, so that it can be efficiently browsed. At coarse levels, the similarity pyramid allows users to view the database as large clusters of similar images. Alternatively, users can 'zoom into' finer levels to view individual images. We discuss relevance feedback for the browsing process, and argue that it is fundamentally different from relevance feedback for more traditional search-by-query tasks. We propose two fundamental operations for active browsing: pruning and reorganization. Both of these operations depend on a user-defined relevance set, which represents the image or set of images desired by the user. We present statistical methods for accurately pruning the database, and we propose a new 'worm hole' distance metric for reorganizing the database, so that members of the relevance set are grouped together.

  3. Biofilm shows spatially stratified metabolic responses to contaminant exposure

    Science.gov (United States)

    Cao, Bin; Majors, Paul D.; Ahmed, Bulbul; Renslow, Ryan S.; Silvia, Crystal P.; Shi, Liang; Kjelleberg, Staffan; Fredrickson, Jim K.; Beyenal, Haluk

    2012-01-01

    Summary Biofilms are core to a range of biological processes, including the bioremediation of environmental contaminants. Within a biofilm population, cells with diverse genotypes and phenotypes coexist, suggesting that distinct metabolic pathways may be expressed based on the local environmental conditions in a biofilm. However, metabolic responses to local environmental conditions in a metabolically active biofilm interacting with environmental contaminants have never been quantitatively elucidated. In this study, we monitored the spatiotemporal metabolic responses of metabolically active Shewanella oneidensis MR-1 biofilms to U(VI) (uranyl, UO22+) and Cr(VI) (chromate, CrO42−) using noninvasive nuclear magnetic resonance imaging (MRI) and spectroscopy (MRS) approaches to obtain insights into adaptation in biofilms during biofilm-contaminant interactions. While overall biomass distribution was not significantly altered upon exposure to U(VI) or Cr(VI), MRI and spatial mapping of the diffusion revealed localized changes in the water diffusion coefficients in the biofilms, suggesting significant contaminant-induced changes in structural or hydrodynamic properties during bioremediation. Finally, we quantitatively demonstrated that the metabolic responses of biofilms to contaminant exposure are spatially stratified, implying that adaptation in biofilms is custom-developed based on local microenvironments. PMID:22925136

  4. Raw Materials Synthesis from Heavy Metal Industry Effluents with Bioremediation and Phytomining: A Biomimetic Resource Management Approach

    OpenAIRE

    Karman, Salmah B.; S. Zaleha M. Diah; Gebeshuber, Ille C.

    2015-01-01

    Heavy metal wastewater poses a threat to human life and causes significant environmental problems. Bioremediation provides a sustainable waste management technique that uses organisms to remove heavy metals from contaminated water through a variety of different processes. Biosorption involves the use of biomass, such as plant extracts and microorganisms (bacteria, fungi, algae, yeast), and represents a low-cost and environmentally friendly method of bioremediation and resource management. Bio...

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

    OpenAIRE

    Fariba Mohsenzadeh; Abdolkarim Chehregani Rad; Mehrangiz Akbari

    2012-01-01

    Abstract 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 ch...

  6. Resistance of Solid-Phase U(VI) to Microbial Reduction during In Situ Bioremediation of Uranium-Contaminated Groundwater

    OpenAIRE

    Ortiz-Bernad, Irene; Anderson, Robert T.; Vrionis, Helen A.; Lovley, Derek R.

    2004-01-01

    Speciation of solid-phase uranium in uranium-contaminated subsurface sediments undergoing uranium bioremediation demonstrated that although microbial reduction of soluble U(VI) readily immobilized uranium as U(IV), a substantial portion of the U(VI) in the aquifer was strongly associated with the sediments and was not microbially reducible. These results have important implications for in situ uranium bioremediation strategies.

  7. Bioremediation of CCA-Treated Wood By Brown-Rot Fungi Fomitopsis Palustris, Coniophora Puteana, and Laetiporus Sulphureus

    OpenAIRE

    Kartal, S Nami; Munir, Erman; Kamitani, Tomo

    2008-01-01

    This study evaluated oxalic acid accumulation and bioremediation of chromated copper arscnate (CCA)-treated wood by three brown-rot fungi Fomitopsis palustris Coniophora puteane, and Laetiporus sulphureas. The fungi were first cultivated in a fermentation broth to accumulate oxalic acid. Bioremediation of CCA-treated wood was then carried out by leaching of heavy metals with oxalic acid over a 10-day fermentation period. Higher amounts of oxalic acid were produced by F. polustris and L. sulp...

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

    Science.gov (United States)

    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

  9. Design and field-scale implementation of an “on site” bioremediation treatment in PAH-polluted soil

    International Nuclear Information System (INIS)

    An “on site” bioremediation program was designed and implemented in soil polluted with polycyclic aromatic hydrocarbons (PAHs), especially naphthalene. We began by characterizing the soil's physical and chemical properties. A microbiological screening corroborated the presence of microorganisms capable of metabolizing PAHs. We then analyzed the viability of bioremediation by developing laboratory microcosms and pilot scale studies, to optimize the costs and time associated with remediation. The treatment assays were based on different types of biostimulants, such as a slow or fast-release fertilizer, combined with commercial surfactants. Once the feasibility of the biostimulation was confirmed, a real-scale bioremediation program was undertaken in 900 m3 of contaminated soil. The three-step design reduced PAH contamination by 94.4% at the end of treatment (161 days). The decrease in pollutants was concomitant with the selection of autochthonous bacteria capable of degrading PAHs, with Bacillus and Pseudomonas the most abundant genera. -- Highlights: •A three-step bioremediation program was designed for a polluted soil with PAHs. •Biostimulation was based in applying nutrient plus surfactants, watering and aeration. •Microcosm and pilot scale studies allowed the selection of the best treatment. •Bioremediation of 900 m3 of contaminated soil showed a final reduction of 94.4% PAHs. •Autochthonous Bacillus and Pseudomonas were the bacterial genera with highest representation. -- PAH-polluted soil underwent biostimulation at the microcosms and pilot-scale to optimize subsequent field-scale bioremediation

  10. Importance of soil-water relation in assessment endpoint in bioremediated soils: Plant growth and soil physical properties

    International Nuclear Information System (INIS)

    Much effort has been focused on defining the end-point of bioremediated soils by chemical analysis (Alberta Tier 1 or CCME Guideline for Contaminated Soils) or toxicity tests. However, these tests do not completely assess the soil quality, or the capability of soil to support plant growth after bioremediation. This study compared barley (Hordeum vulgare) growth on: (i) non-contaminated, agricultural topsoil, (2) oil-contaminated soil (4% total extractable hydrocarbons, or TEH), and (3) oil-contaminated soil treated by bioremediation (< 2% TEH). Soil physical properties including water retention, water uptake, and water repellence were measured. The results indicated that the growth of barley was significantly reduced by oil-contamination of agricultural topsoil. Furthermore, bioremediation did not improve the barley yield. The lack of effects from bioremediation was attributed to development of water repellence in hydrocarbon contaminated soils. There seemed to be a critical water content around 18% to 20% in contaminated soils. Above this value the water uptake by contaminated soil was near that of the agricultural topsoil. For lower water contents, there was a strong divergence in sorptivity between contaminated and agricultural topsoil. For these soils, water availability was likely the single most important parameter controlling plant growth. This parameter should be considered in assessing endpoint of bioremediation for hydrocarbon contaminated soils

  11. Enhanced Bioremediation of Soil Artificially Contaminated with Petroleum Hydrocarbons after Amendment with Capra aegagrus hircus (Goat Manure

    Directory of Open Access Journals (Sweden)

    T. P. Nwogu

    2015-01-01

    Full Text Available This study was carried out to evaluate the biostimulant potentials of Capra aegagrus hircus manure for bioremediation of crude oil contaminated soil (COCS under tropical conditions. 1 kg of COCS sample was amended with 0.02 kg of C. a. hircus manure and monitored at 14-day intervals for total petroleum hydrocarbon (TPH, nutrient content, and changes in microbial counts. At the end of the study period, there was 62.08% decrease in the concentration of TPH in the amended sample compared to 8.15% decrease in the unamended sample, with significant differences (P<0.05 in TPH concentrations for both samples at different time intervals. Similarly, there was a gradual decrease in the concentrations of total organic carbon, nitrogen, phosphorus, and potassium in both samples. The culturable hydrocarbon-utilizing bacteria (CHUB increased steadily from 8.5 × 105 cfu/g to 2.70 × 106 cfu/g and from 8.0 × 105 cfu/g to 1.78 × 106 cfu/g for both samples. Acinetobacter, Achromobacter, Bacillus, Flavobacterium, Klebsiella, Micrococcus, Pseudomonas, and Staphylococcus were isolated from amended sample with Pseudomonas being the predominant isolated bacterial genus. This study demonstrated that C. a. hircus manure is a good biostimulant, which enhanced the activities of indigenous hydrocarbonoclastic bacteria resulting in significant decrease in TPH concentration of COCS.

  12. Enhanced Bioremediation of Soil Artificially Contaminated with Petroleum Hydrocarbons after Amendment with Capra aegagrus hircus (Goat) Manure

    Science.gov (United States)

    Nwogu, T. P.; Azubuike, C. C.; Ogugbue, C. J.

    2015-01-01

    This study was carried out to evaluate the biostimulant potentials of Capra aegagrus hircus manure for bioremediation of crude oil contaminated soil (COCS) under tropical conditions. 1 kg of COCS sample was amended with 0.02 kg of C. a. hircus manure and monitored at 14-day intervals for total petroleum hydrocarbon (TPH), nutrient content, and changes in microbial counts. At the end of the study period, there was 62.08% decrease in the concentration of TPH in the amended sample compared to 8.15% decrease in the unamended sample, with significant differences (P < 0.05) in TPH concentrations for both samples at different time intervals. Similarly, there was a gradual decrease in the concentrations of total organic carbon, nitrogen, phosphorus, and potassium in both samples. The culturable hydrocarbon-utilizing bacteria (CHUB) increased steadily from 8.5 × 105 cfu/g to 2.70 × 106 cfu/g and from 8.0 × 105 cfu/g to 1.78 × 106 cfu/g for both samples. Acinetobacter, Achromobacter, Bacillus, Flavobacterium, Klebsiella, Micrococcus, Pseudomonas, and Staphylococcus were isolated from amended sample with Pseudomonas being the predominant isolated bacterial genus. This study demonstrated that C. a. hircus manure is a good biostimulant, which enhanced the activities of indigenous hydrocarbonoclastic bacteria resulting in significant decrease in TPH concentration of COCS. PMID:26770830

  13. Solarization and biosolarization using organic wastes for the bioremediation of soil polluted with terbuthylazine and linuron residues.

    Science.gov (United States)

    Fenoll, José; Hellín, Pilar; Flores, Pilar; Lacasa, Alfredo; Navarro, Simón

    2014-10-01

    Strategies for remediation of polluted soils are needed to accelerate the degradation and natural attenuation of pesticides. This study was conducted to assess the effect of solarization (S) and biosolarization (BS) during the summer season using organic wastes (composted sheep manure and sugar beet vinasse) for the bioremediation of soil containing residues of terbuthylazine and linuron. The results showed that both S and BS enhanced herbicide dissipation rates compared with the non-disinfected control, an effect which was attributed to the increased soil temperature and organic matter. Linuron showed similar behavior under S and BS conditions. However, terbuthylazine was degraded to a greater extent in the biosolarization experiment using sugar beet vinasse than in the both the solarization and biosolarization experiments using composted sheep manure treatments. The main organic intermediates detected during the degradation of terbuthylazine and linuron were identified, enabling the main steps of degradation to be proposed. The results confirm that both S and BS techniques can be considered as a remediation tools for polluted soils containing these herbicides.

  14. Spatial alexia.

    Science.gov (United States)

    Ardila, A; Rosselli, M

    1994-05-01

    Twenty-one patients with right hemisphere damage were studied (11 men, 10 women; average age = 41.33; range = 19-65). Patients were divided in two groups: pre-Rolandic (six patients) and retro-Rolandic (15 patients) right hemisphere damage. A special reading test was given to each patient. The observed errors included: literal errors (substitutions, additions, and omissions of letters), substitutions of syllables and pseudowords for meaningful words, left hemispatial neglect, confabulation, splitting of words, verbal errors (substitutions, additions, and omission of words), grouping of letters belonging to two different words, misuse of punctuation marks, and errors in following lines. It was proposed that spatial alexia is characterized by: (1) some difficulties in the recognition of the spatial orientation in letters; (2) left hemispatial neglect; (3) tendency to "complete" the sense of words and sentences; (4) inability to follow lines when reading texts, and sequentially explore the spatial distribution of the written material; and (5) grouping and fragmentation of words, most likely as a consequence of the inability to interpret the relative value of spaces between letters correctly. PMID:7960468

  15. Mechanisms for similarity based cooperation

    Science.gov (United States)

    Traulsen, A.

    2008-06-01

    Cooperation based on similarity has been discussed since Richard Dawkins introduced the term “green beard” effect. In these models, individuals cooperate based on an aribtrary signal (or tag) such as the famous green beard. Here, two different models for such tag based cooperation are analysed. As neutral drift is important in both models, a finite population framework is applied. The first model, which we term “cooperative tags” considers a situation in which groups of cooperators are formed by some joint signal. Defectors adopting the signal and exploiting the group can lead to a breakdown of cooperation. In this case, conditions are derived under which the average abundance of the more cooperative strategy exceeds 50%. The second model considers a situation in which individuals start defecting towards others that are not similar to them. This situation is termed “defective tags”. It is shown that in this case, individuals using tags to cooperate exclusively with their own kind dominate over unconditional cooperators.

  16. Microarray and Real-Time PCR Analyses of the Responses of High-Arctic Soil Bacteria to Hydrocarbon Pollution and Bioremediation Treatments▿

    OpenAIRE

    Yergeau, Etienne; Arbour, Mélanie; Brousseau, Roland; Juck, David; Lawrence, John R.; Masson, Luke; Whyte, Lyle G; Greer, Charles W.

    2009-01-01

    High-Arctic soils have low nutrient availability, low moisture content, and very low temperatures and, as such, they pose a particular problem in terms of hydrocarbon bioremediation. An in-depth knowledge of the microbiology involved in this process is likely to be crucial to understand and optimize the factors most influencing bioremediation. Here, we compared two distinct large-scale field bioremediation experiments, located at the Canadian high-Arctic stations of Alert (ex situ approach) a...

  17. Monitoring of ground water quality and heavy metals in soil during large scale bioremediation of petroleum hydrocarbon contaminated waste in India: case studies

    OpenAIRE

    Ajoy Kumar Mandal; Atanu Jana; Mr. Abhijit Datta; Sarma, Priyangshu M.; Banwari Lal; Jayati Datta

    2014-01-01

    Bioremediation using microbes has been well accepted as an environmentally friendly and economical treatment method for disposal of hazardous petroleum hydrocarbon contaminated waste (oily waste) and this type of bioremediation has been successfully conducted in laboratory and on a pilot scale in various countries, including India. Presently there are no federal regulatory guidelines available in India for carrying out field-scale bioremediation of oily waste using microbes. The results of th...

  18. The Gestalt principle of similarity benefits visual working memory.

    Science.gov (United States)

    Peterson, Dwight J; Berryhill, Marian E

    2013-12-01

    Visual working memory (VWM) is essential for many cognitive processes, yet it is notably limited in capacity. Visual perception processing is facilitated by Gestalt principles of grouping, such as connectedness, similarity, and proximity. This introduces the question, do these perceptual benefits extend to VWM? If so, can this be an approach to enhance VWM function by optimizing the processing of information? Previous findings have demonstrated that several Gestalt principles (connectedness, common region, and spatial proximity) do facilitate VWM performance in change detection tasks (Jiang, Olson, & Chun, 2000; Woodman, Vecera, & Luck, 2003; Xu, 2002, 2006; Xu & Chun, 2007). However, one prevalent Gestalt principle, similarity, has not been examined with regard to facilitating VWM. Here, we investigated whether grouping by similarity benefits VWM. Experiment 1 established the basic finding that VWM performance could benefit from grouping. Experiment 2 replicated and extended this finding by showing that similarity was only effective when the similar stimuli were proximal. In short, the VWM performance benefit derived from similarity was constrained by spatial proximity, such that similar items need to be near each other. Thus, the Gestalt principle of similarity benefits visual perception, but it can provide benefits to VWM as well.

  19. Bioremediation via Methanotrophy: Overview of Recent Findings and Suggestions for Future Research

    Directory of Open Access Journals (Sweden)

    Jeremy eSemrau

    2011-10-01

    Full Text Available Microbially-mediated bioremediation of polluted sites has been a subject of much research over the past 30 years, with many different compounds shown to be degraded under both aerobic and anaerobic conditions. Aerobic-mediated bioremediation commonly examines the use of methanotrophs, microorganisms that consume methane as their sole source of carbon and energy. Given the diverse environments in which methanotrophs have been found, the range of substrates they can degrade and the fact that they can be easily stimulated with the provision of methane and oxygen, these microorganisms in particular have been examined for aerobic degradation of chlorinated hydrocarbons. The physiological and phylogenetic diversity of methanotrophy, however, has increased substantially in just the past five years. Here in this review, the current state of knowledge of methanotrophy, particularly as it applies to pollutant degradation is summarized, and suggestions for future research provided.

  20. Application of statistical experimental methodology to optimize bioremediation of n-alkanes in aquatic environment

    International Nuclear Information System (INIS)

    Response surface methodology (RSM) was employed to optimize nitrogen and phosphorus concentrations for removal of n-alkanes from crude oil contaminated seawater samples in batch reactors. Erlenmeyer flasks were used as bioreactors; each containing 250 mL dispersed crude oil contaminated seawater, indigenous acclimatized microorganism and different amounts of nitrogen and phosphorus based on central composite design (CCD). Samples were extracted and analyzed according to US-EPA protocols using a gas chromatograph. During 28 days of bioremediation, a maximum of 95% total aliphatic hydrocarbons removal was observed. The obtained Model F-value of 267.73 and probability F < 0.0001 implied the model was significant. Numerical condition optimization via a quadratic model, predicted 98% n-alkanes removal for a 20-day laboratory bioremediation trial using nitrogen and phosphorus concentrations of 13.62 and 1.39 mg/L, respectively. In actual experiments, 95% removal was observed under these conditions.

  1. Biological sand filters: low-cost bioremediation technique for production of clean drinking water.

    Science.gov (United States)

    Lea, Michael

    2014-05-01

    Approximately 1.1 billion people in rural and peri-urban communities of developing countries do not have access to safe drinking water. The mortality from diarrheal-related diseases amounts to ∼2.2 million people each year from the consumption of unsafe water. Most of them are children under 5 years of age--250 deaths an hour from microbiologically contaminated water. There is conclusive evidence that one low-cost household bioremediation intervention, use of biological sand filters, is capable of dramatically improving the microbiological quality of drinking water. This unit will describe this relatively new and proven bioremediation technology's ability to empower at-risk populations to use naturally occurring biological principles and readily available materials as a sustainable way to achieve the health benefits of safe drinking water.

  2. Evaluation of Four Bio fertilizers for Bioremediation of Pesticide contaminated Soil

    International Nuclear Information System (INIS)

    Experiments were conducted to asses the ability of mixed populations of microorganisms which produced as a bio fertilizers by the General Organization of Agriculture Fund, Ministry of Agriculture, Egypt (phosphoren, microbien, cerealin and azospirillum) to degrade five selected pesticides representing different classes including organophosphate, carbamate and chlorinated organic compounds. There were differences in rates of biotransformation, suggesting the selective induction of certain metabolic enzymes. Inoculation of soil incorporated with malathion, fenamiphos, carbaryl, aldicarb and dieldrin, resulted in ca. 80-90% removal of malathion and fenamiphos within 8 days, carbaryl and aldicarb within 11-15 days respectively. Dieldrin removal occurred slowly within 2 months. These data suggest that bioremediate may act as potential candidates for soil inoculation to bioremediate pesticide contaminated soil. The production of Co2 (soil respiration ) was stimulated by some pesticides. In samples with microbien, an about 2 times higher Co2 production was measured

  3. Downscaling the in vitro test of fungal bioremediation of polycyclic aromatic hydrocarbons: methodological approach.

    Science.gov (United States)

    Drevinskas, Tomas; Mickienė, Rūta; Maruška, Audrius; Stankevičius, Mantas; Tiso, Nicola; Mikašauskaitė, Jurgita; Ragažinskienė, Ona; Levišauskas, Donatas; Bartkuvienė, Violeta; Snieškienė, Vilija; Stankevičienė, Antanina; Polcaro, Chiara; Galli, Emanuela; Donati, Enrica; Tekorius, Tomas; Kornyšova, Olga; Kaškonienė, Vilma

    2016-02-01

    The miniaturization and optimization of a white rot fungal bioremediation experiment is described in this paper. The optimized procedure allows determination of the degradation kinetics of anthracene. The miniaturized procedure requires only 2.5 ml of culture medium. The experiment is more precise, robust, and better controlled comparing it to classical tests in flasks. Using this technique, different parts, i.e., the culture medium, the fungi, and the cotton seal, can be analyzed. A simple sample preparation speeds up the analytical process. Experiments performed show degradation of anthracene up to approximately 60% by Irpex lacteus and up to approximately 40% by Pleurotus ostreatus in 25 days. Bioremediation of anthracene by the consortium of I. lacteus and P. ostreatus shows the biodegradation of anthracene up to approximately 56% in 23 days. At the end of the experiment, the surface tension of culture medium decreased comparing it to the blank, indicating generation of surfactant compounds. PMID:26660875

  4. [Bioremediation of petroleum hydrocarbon-contaminated soils by cold-adapted microorganisms: research advance].

    Science.gov (United States)

    Wang, Shi-jie; Wang, Xiang; Lu, Gui-lan; Wang, Qun-hui; Li, Fa-sheng; Guo, Guan-lin

    2011-04-01

    Cold-adapted microorganisms such as psychrotrophs and psychrophiles widely exist in the soils of sub-Arctic, Arctic, Antarctic, alpine, and high mountains, being the important microbial resources for the biodegradation of petroleum hydrocarbons at low temperature. Using the unique advantage of cold-adapted microorganisms to the bioremediation of petroleum hydrocarbon-contaminated soils in low temperature region has become a research hotspot. This paper summarized the category and cold-adaptation mechanisms of the microorganisms able to degrade petroleum hydrocarbon at low temperature, biodegradation characteristics and mechanisms of different petroleum fractions under the action of cold-adapted microorganisms, bio-stimulation techniques for improving biodegradation efficiency, e. g., inoculating petroleum-degrading microorganisms and adding nutrients or bio-surfactants, and the present status of applying molecular biotechnology in this research field, aimed to provide references to the development of bioremediation techniques for petroleum hydrocarbon-contaminated soils.

  5. Isolation, identification and characterization of fluoride resistant bacteria: possible role in bioremediation.

    Science.gov (United States)

    Chouhan, S; Tuteja, U; Flora, S J S

    2012-01-01

    Microorganisms found in industrial effluents and near the sites of the contamination can be used to indicate pollution and detoxify the contaminated water resources. Emergence of xenobiotic resistant bacteria among them might be potential application in bioremediation. The objective of this study was to isolate and characterize fluoride resistant bacteria from soil and water samples of different regions of India. Five isolates were recovered from different samples which were found to be fluoride resistant. Two of them effectively reduced the fluoride from their media. Through the current study it can be predicted that fluoride pollution results in selective pressure that leads to the development of fluoride resistant among bacterial populations, probably through the mechanism which involved high affinity anion binding compounds called ionophores. Resistant microbes may play a bioremediative role by transforming and concentrating these anions so that they are less available and less dangerous. PMID:22567885

  6. In silico Analysis for Laccase-mediated Bioremediation of the Emerging Pharmaceutical Pollutants

    Directory of Open Access Journals (Sweden)

    Anjali Singh

    2015-12-01

    Full Text Available Laccases, a copper oxidase enzyme, has been employed for bioremediation of anthropogenic pollutants in the recent past. Laccase has a broad range of substrate specificity which offers the prospect for screening in numerable xenobiotics. The present study was aimed to use protein-ligand docking as a tool for prediction of biodegradation of selected pharmaceutical pollutants. A comparative study was also done to determine the binding efficacy of bacterial and fungal laccase for those selected pollutants. The laccase-pollutant docking was carried out using HEX software. The docking scores of bacterial and fungal laccase for predefined pollutants were comparable to ABTS, a substrate for laccase, which suggested that laccase might be able to degrade emerging pharmaceutical pollutants. The docking analysis approach can be useful in prediction of binding competence of pharmaceutical pollutants with laccase for in situ laccase-mediated bioremediation.

  7. Bioremediation strategies of hydrocarbons and microbial diversity in the Trindade Island shoreline--Brazil.

    Science.gov (United States)

    Rodrigues, Edmo M; Kalks, Karlos H M; Fernandes, Péricles L; Tótola, Marcos R

    2015-12-30

    This study analyzed the microbial diversity colonizing the surface of an oil sample during its contact with water, off the Trindade Island coast and simulated the efficiency of eight different bioremediation strategies for this environment. The diversity analysis was performed using acrylic coupons that served as the support for an oil inclusion at sea. The coupons were sampled over 30 days, and T-RFLP multiplex was employed to access the diversity of fungi, Bacteria and Archaea present on the oil surface. The bioremediation strategies were simulated in a respirometer. The results showed that the bacterial domain was the most dominant in oil colonization and that the richness of the species attached to the oil gradually increases with the exposure time of the coupons. The combination of biostimulation and bioaugmentation with a native population was proven to be an effective strategy for the remediation of oil off the Trindade Island shoreline.

  8. Ecosystem protection by effluent bioremediation: silver nanoparticles impregnation in a textile fabrics process

    Energy Technology Data Exchange (ETDEWEB)

    Duran, Nelson, E-mail: duran@iqm.unicamp.br; Marcato, Priscyla D. [Universidade Estadual de Campinas, Biological Chemistry Laboratory, Instituto de Quimica (Brazil); Alves, Oswaldo L. [Universidade Estadual de Campinas, Solid State Chemistry Laboratory, Instituto de Quimica (Brazil); Silva, Joao P. S. Da; Souza, Gabriel I. H. De [Universidade de Mogi das Cruzes, Biological Chemistry and Biotechnology Laboratory, Environmental Sciences Center (Brazil); Rodrigues, Flavio A. [Universidade de Mogi das Cruzes, Material Chemistry Laboratory, Biochemical Research Center (Brazil); Esposito, Elisa [Universidade de Mogi das Cruzes, Biological Chemistry and Biotechnology Laboratory, Environmental Sciences Center (Brazil)

    2010-01-15

    This work studied a bioremediation process of silver nanoparticles with the bacterium Chromobacterium violaceum. These nanoparticles were obtained from several washes of cotton fabrics impregnated with silver nanoparticles produced by the fungus Fusarium oxysporum. The optimized growth of C. violaceum for silver nanoparticles bioremediation was obtained. The effluents of wash process of the cotton fabric were efficiently treated with C. violaceum. This treatment was based on biosorption which was very efficient for the elimination of silver nanoparticles remaining in the wash water. The bacteria after biosorption were morphologically transformed, but the normal morphology after a new culture was completely restored. The process also allowed the recovery of silver material that was leached into the effluent for a reutilization avoiding any effect to the eco-environment.

  9. Potential of non-ligninolytic fungi in bioremediation of chlorinated and polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Marco-Urrea, Ernest; García-Romera, Inmaculada; Aranda, Elisabet

    2015-12-25

    In previous decades, white-rot fungi as bioremediation agents have been the subjects of scientific research due to the potential use of their unspecific oxidative enzymes. However, some non-white-rot fungi, mainly belonging to the Ascomycota and Zygomycota phylum, have demonstrated their potential in the enzymatic transformation of environmental pollutants, thus overcoming some of the limitations observed in white-rot fungi with respect to growth in neutral pH, resistance to adverse conditions and the capacity to surpass autochthonous microorganisms. Despite their presence in so many soil and water environments, little information exists on the enzymatic mechanisms and degradation pathways involved in the transformation of hydrocarbons by these fungi. This review describes the bioremediation potential of non-ligninolytic fungi with respect to chlorinated hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) and also shows known conversion pathways and the prospects for future research.

  10. Role of Microbial Enzymes in the Bioremediation of Pollutants: A Review

    Directory of Open Access Journals (Sweden)

    Chandrakant S. Karigar

    2011-01-01

    Full Text Available A large number of enzymes from bacteria, fungi, and plants have been reported to be involved in the biodegradation of toxic organic pollutants. Bioremediation is a cost effective and nature friendly biotechnology that is powered by microbial enzymes. The research activity in this area would contribute towards developing advanced bioprocess technology to reduce the toxicity of the pollutants and also to obtain novel useful substances. The information on the mechanisms of bioremediation-related enzymes such as oxido-reductases and hydrolases have been extensively studied. This review attempts to provide descriptive information on the enzymes from various microorganisms involved in the biodegradation of wide range of pollutants, applications, and suggestions required to overcome the limitations of their efficient use.

  11. Potential of bioremediation for buried oil removal in beaches after an oil spill.

    Science.gov (United States)

    Pontes, Joana; Mucha, Ana P; Santos, Hugo; Reis, Izabela; Bordalo, Adriano; Basto, M Clara; Bernabeu, Ana; Almeida, C Marisa R

    2013-11-15

    Bioremediation potential for buried oil removal, an application still lacking thorough research, was assessed in a specifically designed system in which an artificially contaminated oil layer of sand was buried in a sand column subjected to tidal simulation. The efficiency of biostimulation (BS, fertilizer addition) and bioaugmentation (BA, inoculation of pre-stimulated indigenous hydrocarbon-degrading microorganisms plus fertilizer) compared to natural attenuation was tested during a 180-day experimental period. The effect of BA was evident after 60 days (degradation of hydrocarbons reached 80%). BS efficacy was revealed only after 120 days. Microorganisms and nutrients added at the top of the sand column were able to reach the buried oil layer and contributed to faster oil elimination, an important feature for effective bioremediation treatments. Therefore, autochthonous BA with suitable nutritive conditions results in faster oil-biodegradation, appears to be a cost-effective methodology for buried oil remediation and contributes to the recovery of oil-impacted areas.

  12. Implications of nitrogen fertilization for in-situ bioremediation of petroleum-contaminated soils

    International Nuclear Information System (INIS)

    In situ bioremediation is a promising and rapidly evolving technology for the cleanup of contaminated soils. Although the principles of biodegradation are not new, they are being applied to field remediations in novel ways. Likewise, the metabolic requirements for nitrogen and phosphorus during biodegradation are well-established. However, their effect on the quality of biodegradation still needs delineation. In addition to the physiological effects of mineral nutrients, their mobility and bioavailability in soil becomes critical during an in-situ bioremediation. Studies in the authors laboratory have investigated the effect of different types of fertilizers on hydrocarbon biodegradation in a variety of contaminated soils. Results indicate that the amount and/or species of fertilizer may affect not only the rate of biodegradation, but also the quality of biodegradation, i.e. mineralization of CO2

  13. Potential of bioremediation for buried oil removal in beaches after an oil spill.

    Science.gov (United States)

    Pontes, Joana; Mucha, Ana P; Santos, Hugo; Reis, Izabela; Bordalo, Adriano; Basto, M Clara; Bernabeu, Ana; Almeida, C Marisa R

    2013-11-15

    Bioremediation potential for buried oil removal, an application still lacking thorough research, was assessed in a specifically designed system in which an artificially contaminated oil layer of sand was buried in a sand column subjected to tidal simulation. The efficiency of biostimulation (BS, fertilizer addition) and bioaugmentation (BA, inoculation of pre-stimulated indigenous hydrocarbon-degrading microorganisms plus fertilizer) compared to natural attenuation was tested during a 180-day experimental period. The effect of BA was evident after 60 days (degradation of hydrocarbons reached 80%). BS efficacy was revealed only after 120 days. Microorganisms and nutrients added at the top of the sand column were able to reach the buried oil layer and contributed to faster oil elimination, an important feature for effective bioremediation treatments. Therefore, autochthonous BA with suitable nutritive conditions results in faster oil-biodegradation, appears to be a cost-effective methodology for buried oil remediation and contributes to the recovery of oil-impacted areas. PMID:24054785

  14. Enzymatic hydrolysis and characterization of waste lignocellulosic biomass produced after dye bioremediation under solid state fermentation.

    Science.gov (United States)

    Waghmare, Pankajkumar R; Kadam, Avinash A; Saratale, Ganesh D; Govindwar, Sanjay P

    2014-09-01

    Sugarcane bagasse (SCB) adsorbes 60% Reactive Blue172 (RB172). Providensia staurti EbtSPG able to decolorize SCB adsorbed RB172 up to 99% under solid state fermentation (SSF). The enzymatic saccharification efficiency of waste biomass after bioremediation of RB172 process (ddSCB) has been evaluated. The cellulolyitc crude enzyme produced by Phanerochaete chrysosporium used for enzymatic hydrolysis of native SCB and ddSCB which produces 0.08 and 0.3 g/L of reducing sugars respectively after 48 h of incubation. The production of hexose and pentose sugars during hydrolysis was confirmed by HPTLC. The effect of enzymatic hydrolysis on SCB and ddSCB has been evaluated by FTIR, XRD and SEM analysis. Thus, during dye biodegradation under SSF causes biological pretreatment of SCB which significantly enhanced its enzymatic saccharification. Adsorption of dye on SCB, its bioremediation under SSF produces wastes biomass and which further utilized for enzymatic saccharification for biofuel production.

  15. The Influence of Soil Chemical Factors on In Situ Bioremediation of Soil Contamination

    Energy Technology Data Exchange (ETDEWEB)

    Breedveld, Gijs D.

    1997-12-31

    Mineral oil is the major energy source in Western society. Production, transport and distribution of oil and oil products cause serious contamination problems of water, air and soil. The present thesis studies the natural biodegradation processes in the soil environment which can remove contamination by oil products and creosote. The main physical/chemical processes determining the distribution of organic contaminants between the soil solid, aqueous and vapour phase are discussed. Then a short introduction to soil microbiology and environmental factors important for biodegradation is given. There is a discussion of engineered and natural bioremediation methods and the problems related to scaling up laboratory experiments to field scale remediation. Bioremediation will seldom remove the contaminants completely; a residue remains. Factors affecting the level of residual contamination and the consequences for contaminant availability are discussed. Finally, the main findings of the work are summarized and recommendations for further research are given. 111 refs., 41 figs., 19 tabs.

  16. Mega Borg oil spill of the Texas coast: An open-water bioremediation test

    International Nuclear Information System (INIS)

    Nature has developed hydrocarbons as a part of life. Since the origin of life, more than 60,000 organic molecules have evolved that make up protoplasm; a given percentage of these molecules are hydrocarbons. Commercial hydrocarbon deposits are a by-product of this natural process and a continual source of oil in the aquatic environment through seeps. As a result, nature has also evolved a recycling system for the hydrocarbons. This cycle is the basis for a program of bioremediation using microorganisms. Effort has been made to develop mixed cultures capable of a wide range of hydrocarbon metabolism and co-metabolism. The cultures are economically produced in high concentrations as a dry powder with a shelf life of one year. The result is an economical process for the application of bacteria to hydrocarbon pollutants on water and soils. The process of bioremediation to the recent Mega Borg accident will be discussed

  17. Biofilm lifestyle enhances diesel bioremediation and biosurfactant production in the Antarctic polyhydroxyalkanoate producer Pseudomonas extremaustralis.

    Science.gov (United States)

    Tribelli, Paula M; Di Martino, Carla; López, Nancy I; Raiger Iustman, Laura J

    2012-09-01

    Diesel is a widely distributed pollutant. Bioremediation of this kind of compounds requires the use of microorganisms able to survive and adapt to contaminated environments. Pseudomonas extremaustralis is an Antarctic bacterium with a remarkable survival capability associated to polyhydroxyalkanoates (PHAs) production. This strain was used to investigate the effect of cell growth conditions--in biofilm versus shaken flask cultures--as well as the inocula characteristics associated with PHAs accumulation, on diesel degradation. Biofilms showed increased cell growth, biosurfactant production and diesel degradation compared with that obtained in shaken flask cultures. PHA accumulation decreased biofilm cell attachment and enhanced biosurfactant production. Degradation of long-chain and branched alkanes was observed in biofilms, while in shaken flasks only medium-chain length alkanes were degraded. This work shows that the PHA accumulating bacterium P. extremaustralis can be a good candidate to be used as hydrocarbon bioremediation agent, especially in extreme environments.

  18. Semantically enabled image similarity search

    Science.gov (United States)

    Casterline, May V.; Emerick, Timothy; Sadeghi, Kolia; Gosse, C. A.; Bartlett, Brent; Casey, Jason

    2015-05-01

    Georeferenced data of various modalities are increasingly available for intelligence and commercial use, however effectively exploiting these sources demands a unified data space capable of capturing the unique contribution of each input. This work presents a suite of software tools for representing geospatial vector data and overhead imagery in a shared high-dimension vector or embedding" space that supports fused learning and similarity search across dissimilar modalities. While the approach is suitable for fusing arbitrary input types, including free text, the present work exploits the obvious but computationally difficult relationship between GIS and overhead imagery. GIS is comprised of temporally-smoothed but information-limited content of a GIS, while overhead imagery provides an information-rich but temporally-limited perspective. This processing framework includes some important extensions of concepts in literature but, more critically, presents a means to accomplish them as a unified framework at scale on commodity cloud architectures.

  19. Performance Indexes: Similarities and Differences

    Directory of Open Access Journals (Sweden)

    André Machado Caldeira

    2013-06-01

    Full Text Available The investor of today is more rigorous on monitoring a financial assets portfolio. He no longer thinks only in terms of the expected return (one dimension, but in terms of risk-return (two dimensions. Thus new perception is more complex, since the risk measurement can vary according to anyone’s perception; some use the standard deviation for that, others disagree with this measure by proposing others. In addition to this difficulty, there is the problem of how to consider these two dimensions. The objective of this essay is to study the main performance indexes through an empirical study in order to verify the differences and similarities for some of the selected assets. One performance index proposed in Caldeira (2005 shall be included in this analysis.

  20. Features Based Text Similarity Detection

    CERN Document Server

    Kent, Chow Kok

    2010-01-01

    As the Internet help us cross cultural border by providing different information, plagiarism issue is bound to arise. As a result, plagiarism detection becomes more demanding in overcoming this issue. Different plagiarism detection tools have been developed based on various detection techniques. Nowadays, fingerprint matching technique plays an important role in those detection tools. However, in handling some large content articles, there are some weaknesses in fingerprint matching technique especially in space and time consumption issue. In this paper, we propose a new approach to detect plagiarism which integrates the use of fingerprint matching technique with four key features to assist in the detection process. These proposed features are capable to choose the main point or key sentence in the articles to be compared. Those selected sentence will be undergo the fingerprint matching process in order to detect the similarity between the sentences. Hence, time and space usage for the comparison process is r...

  1. Metagenomic analysis of the bioremediation of diesel-contaminated Canadian high arctic soils.

    Directory of Open Access Journals (Sweden)

    Etienne Yergeau

    Full Text Available As human activity in the Arctic increases, so does the risk of hydrocarbon pollution events. On site bioremediation of contaminated soil is the only feasible clean up solution in these remote areas, but degradation rates vary widely between bioremediation treatments. Most previous studies have focused on the feasibility of on site clean-up and very little attention has been given to the microbial and functional communities involved and their ecology. Here, we ask the question: which microorganisms and functional genes are abundant and active during hydrocarbon degradation at cold temperature? To answer this question, we sequenced the soil metagenome of an ongoing bioremediation project in Alert, Canada through a time course. We also used reverse-transcriptase real-time PCR (RT-qPCR to quantify the expression of several hydrocarbon-degrading genes. Pseudomonas species appeared as the most abundant organisms in Alert soils right after contamination with diesel and excavation (t = 0 and one month after the start of the bioremediation treatment (t = 1m, when degradation rates were at their highest, but decreased after one year (t = 1y, when residual soil hydrocarbons were almost depleted. This trend was also reflected in hydrocarbon degrading genes, which were mainly affiliated with Gammaproteobacteria at t = 0 and t = 1m and with Alphaproteobacteria and Actinobacteria at t = 1y. RT-qPCR assays confirmed that Pseudomonas and Rhodococcus species actively expressed hydrocarbon degradation genes in Arctic biopile soils. Taken together, these results indicated that biopile treatment leads to major shifts in soil microbial communities, favoring aerobic bacteria that can degrade hydrocarbons.

  2. Remediation of hydrocarbon contaminants in cold environments : electrokinetically enhanced bioremediation and biodegradable oil sorbents

    OpenAIRE

    Suni, Sonja

    2006-01-01

    Owing to the vast amounts of oil in the world, oil spills are common on land as well as at sea. In addition to oil products, other industrially used hydrocarbons, such as creosote, also contaminate soils. Most hydrocarbons are biodegradable. Hence, bioremediation is an attractive alternative for cleaning up hydrocarbon spills. In cold climate areas, however, biodegradation is often a slow process. The aim of this thesis was to develop efficient, cost-effective, and ecologically sound techniqu...

  3. Bioremediating Oil Spills in Nutrient Poor Ocean Waters Using Fertilized Clay Mineral Flakes: Some Experimental Constraints

    OpenAIRE

    Warr, Laurence N.; André Friese; Florian Schwarz; Frieder Schauer; Portier, Ralph J.; Basirico, Laura M.; Gregory M. Olson

    2013-01-01

    Much oil spill research has focused on fertilizing hydrocarbon oxidising bacteria, but a primary limitation is the rapid dilution of additives in open waters. A new technique is presented for bioremediation by adding nutrient amendments to the oil spill using thin filmed minerals comprised largely of Fullers Earth clay. Together with adsorbed N and P fertilizers, filming additives, and organoclay, clay flakes can be engineered to float on seawater, attach to the oil, and slowly release contai...

  4. Test plan, the Czechowice Oil Refinery bioremediation demonstration of a process waste lagoon. Revision 1

    International Nuclear Information System (INIS)

    The overall objective of the bioremediation project is to provide a cost effective bioremediation demonstration of petroleum contaminated soil at the Czechowice Oil Refinery. Additional objectives include training of personnel, and transfer of this technology by example to Poland, and the Risk Abatement Center for Central and Eastern Europe (RACE). The goal of the remediation is to reduce the risk of PAH compounds in soil and provide a green zone (grassy area) adjacent to the site boundary. Initial project discussions with the Czechowice Oil Refinery resulted in helping the refinery find an immediate cost effective solution for the dense organic sludge in the lagoons. They found that when mixed with other waste materials, the sludge could be sold as a fuel source to local cement kilns. Thus the waste was incinerated and provided a revenue stream for the refinery to cleanup the lagoon. This allowed the bioremediation project to focus on remediation of contaminated soil that unusable as fuel, less recalcitrant and easier to handle and remediate. The assessment identified 19 compounds at the refinery that represented significant risk and would require remediation. These compounds consisted of metals, PAH's, and BTEX. The contaminated soil to be remediated in the bioremediation demonstration contains only PAH (BTEX and metals are not significantly above background concentrations). The final biopile design consists of (1) dewatering and clearing lagoon A to clean clay, (2) adding a 20 cm layer of dolomite with pipes for drainage, leachate collection, air injection, and pH adjustment, (3) adding a 1.1 m layer of contaminated soil mixed with wood chips to improve permeability, and (4) completing the surface with 20 cm of top soil planted with grass

  5. Polychlorinated biphenyls fractioning assessment in aqueous bioremediation assy with phanerochaete chrysosporium

    OpenAIRE

    Sangely, Matthieu; Sablayrolles, Caroline; Vialle, Claire; Strehaiano, Pierre; Thannberger, Laurent; Vignoles, Mireille

    2009-01-01

    Thanks to growing environmental concerns in public opinion, bioremediation processes are more and more used to decontaminate soils from organic compounds. Polychlorinated biphenyls (PCBs) are known to be world wide spread persistent organic pollutants (POPs). The white rot fungus Phanerochaete chrysosporium is able to degrade PCBs in water, and soil As POPs, PCBs can also be adsorbed onto organic matter, such as Phanerochaete chrysosporium mycelium. This study aims at estimating the fractioni...

  6. Improvement of Bioremediation Performance for the Degradation of Petroleum Hydrocarbons in Contaminated Sediments

    OpenAIRE

    Laura Rocchetti; Francesca Beolchini; Maurizio Ciani; Antonio Dell'Anno

    2011-01-01

    Microcosm bioremediation strategies were applied to sediments contaminated with hydrocarbons. Experiments were performed in aerobic conditions in a single-step treatment and in a two-step anaerobic-aerobic treatment. In aerobic conditions, either inorganic nutrients or composts were added to the microcosms, while, in the first anaerobic phase of the two-step experiment, acetate and/or allochthonous sulfate-reducing bacteria were used. After the treatment under anaerobic conditions, samples we...

  7. Residues of endosulfan in surface and subsurface agricultural soil and its bioremediation.

    Science.gov (United States)

    Odukkathil, Greeshma; Vasudevan, Namasivayam

    2016-01-01

    The persistence of many hydrophobic pesticides has been reported by various workers in various soil environments and its bioremediation is a major concern due to less bioavailability. In the present study, the pesticide residues in the surface and subsurface soil in an area of intense agricultural activity in Pakkam Village of Thiruvallur District, Tamilnadu, India, and its bioremediation using a novel bacterial consortium was investigated. Surface (0-15 cm) and subsurface soils (15-30 cm and 30-40 cm) were sampled, and pesticides in different layers of the soil were analyzed. Alpha endosulfan and beta endosulfan concentrations ranged from 1.42 to 3.4 mg/g and 1.28-3.1 mg/g in the surface soil, 0.6-1.4 mg/g and 0.3-0.6 mg/g in the subsurface soil (15-30 cm), and 0.9-1.5 mg/g and 0.34-1.3 mg/g in the subsurface soil (30-40 cm) respectively. Residues of other persistent pesticides were also detected in minor concentrations. These soil layers were subjected to bioremediation using a novel bacterial consortium under a simulated soil profile condition in a soil reactor. The complete removal of alpha and beta endosulfan was observed over 25 days. Residues of endosulfate were also detected during bioremediation, which was subsequently degraded on the 30th day. This study revealed the existence of endosulfan in the surface and subsurface soils and also proved that the removal of such a ubiquitous pesticide in the surface and subsurface environment can be achieved in the field by bioaugumenting a biosurfactant-producing bacterial consortium that degrades pesticides. PMID:26413801

  8. Approach of Bioremediation in Olive Oil and Dairy Industry: A Review

    OpenAIRE

    Amir Hamid; Zohra Bibi; Irum Ghafoor; Zubair Anwar; Jabar Zaman Khan Khattak

    2013-01-01

    Bioremediation methods are a promising way of dealing with soil and subsoil contamination by organic substances. This biodegradation process is supported by micro-organisms which use the organic carbon from the pollutants as energy source and cells building blocks. There are several advantages of the implementation of such methods but mainly they have to do with the lack of interference with the ecology of the ecosystem. This study presents the use of technique in numerous ways such as olive ...

  9. Bioremediation potential of a newly isolate solvent tolerant strain Bacillus thermophilus PS11

    OpenAIRE

    PAYEL SARKAR; SHILPI GHOSH

    2012-01-01

    The increased generation of solvent waste has been stated as one of the most critical environmental problems. Though microbial bioremediation has been widely used for waste treatment but their application in solvent waste treatment is limited since the solvents have toxic effects on the microbial cells. A solvent tolerant strain of Bacillus thermophilus PS11 was isolated from soil by cyclohexane enrichment. Transmission electron micrograph of PS11 showed convoluted cell membrane and accumulat...

  10. Integrative analysis of Geobacter spp. and sulfate-reducing bacteria during uranium bioremediation

    OpenAIRE

    M. Barlett; K. Zhuang; R Mahadevan; Lovley, D.

    2012-01-01

    Enhancing microbial U(VI) reduction with the addition of organic electron donors is a promising strategy for immobilizing uranium in contaminated groundwaters, but has yet to be optimized because of a poor understanding of the factors controlling the growth of various microbial communities during bioremediation. In previous field trials in which acetate was added to the subsurface, there were two distinct phases: an initial phase in which acetate-oxidizing, U(VI)-reducing Geobacter predominat...

  11. Evaluating the efficacy of bioremediating a diesel-contaminated soil using ecotoxicological and bacterial community indices.

    Science.gov (United States)

    Khudur, Leadin Salah; Shahsavari, Esmaeil; Miranda, Ana F; Morrison, Paul D; Nugegoda, Dayanthi; Ball, Andrew S

    2015-10-01

    Diesel represents a common environmental contaminant as a result of operation, storage, and transportation accidents. The bioremediation of diesel in a contaminated soil is seen as an environmentally safe approach to treat contaminated land. The effectiveness of the remediation process is usually assessed by the degradation of the total petroleum hydrocarbon (TPH) concentration, without considering ecotoxicological effects. The aim of this study was to assess the efficacy of two bioremediation strategies in terms of reduction in TPH concentration together with ecotoxicity indices and changes in the bacterial diversity assessed using PCR-denaturing gradient gel electrophoresis (DGGE). The biostimulation strategy resulted in a 90 % reduction in the TPH concentration versus 78 % reduction from the natural attenuation strategy over 12 weeks incubation in a laboratory mesocosm-containing diesel-contaminated soil. In contrast, the reduction in the ecotoxicity resulting from the natural attenuation treatment using the Microtox and earthworm toxicity assays was more than double the reduction resulting from the biostimulation treatment (45 and 20 % reduction, respectively). The biostimulated treatment involved the addition of nitrogen and phosphorus in order to stimulate the microorganisms by creating an optimal C:N:P molar ratio. An increased concentration of ammonium and phosphate was detected in the biostimulated soil compared with the naturally attenuated samples before and after the remediation process. Furthermore, through PCR-DGGE, significant changes in the bacterial community were observed as a consequence of adding the nutrients together with the diesel (biostimulation), resulting in the formation of distinctly different bacterial communities in the soil subjected to the two strategies used in this study. These findings indicate the suitability of both bioremediation approaches in treating hydrocarbon-contaminated soil, particularly biostimulation. Although

  12. Residues of endosulfan in surface and subsurface agricultural soil and its bioremediation.

    Science.gov (United States)

    Odukkathil, Greeshma; Vasudevan, Namasivayam

    2016-01-01

    The persistence of many hydrophobic pesticides has been reported by various workers in various soil environments and its bioremediation is a major concern due to less bioavailability. In the present study, the pesticide residues in the surface and subsurface soil in an area of intense agricultural activity in Pakkam Village of Thiruvallur District, Tamilnadu, India, and its bioremediation using a novel bacterial consortium was investigated. Surface (0-15 cm) and subsurface soils (15-30 cm and 30-40 cm) were sampled, and pesticides in different layers of the soil were analyzed. Alpha endosulfan and beta endosulfan concentrations ranged from 1.42 to 3.4 mg/g and 1.28-3.1 mg/g in the surface soil, 0.6-1.4 mg/g and 0.3-0.6 mg/g in the subsurface soil (15-30 cm), and 0.9-1.5 mg/g and 0.34-1.3 mg/g in the subsurface soil (30-40 cm) respectively. Residues of other persistent pesticides were also detected in minor concentrations. These soil layers were subjected to bioremediation using a novel bacterial consortium under a simulated soil profile condition in a soil reactor. The complete removal of alpha and beta endosulfan was observed over 25 days. Residues of endosulfate were also detected during bioremediation, which was subsequently degraded on the 30th day. This study revealed the existence of endosulfan in the surface and subsurface soils and also proved that the removal of such a ubiquitous pesticide in the surface and subsurface environment can be achieved in the field by bioaugumenting a biosurfactant-producing bacterial consortium that degrades pesticides.

  13. Model-based analysis of the role of biological, hydrological and geochemical factors affecting uranium bioremediation.

    Science.gov (United States)

    Zhao, Jiao; Scheibe, Timothy D; Mahadevan, R

    2011-07-01

    Uranium contamination is a serious concern at several sites motivating the development of novel treatment strategies such as the Geobacter-mediated reductive immobilization of uranium. However, this bioremediation strategy has not yet been optimized for the sustained uranium removal. While several reactive-transport models have been developed to represent Geobacter-mediated bioremediation of uranium, these models often lack the detailed quantitative description of the microbial process (e.g., biomass build-up in both groundwater and sediments, electron transport system, etc.) and the interaction between biogeochemical and hydrological process. In this study, a novel multi-scale model was developed by integrating our recent model on electron capacitance of Geobacter (Zhao et al., 2010) with a comprehensive simulator of coupled fluid flow, hydrologic transport, heat transfer, and biogeochemical reactions. This mechanistic reactive-transport model accurately reproduces the experimental data for the bioremediation of uranium with acetate amendment. We subsequently performed global sensitivity analysis with the reactive-transport model in order to identify the main sources of prediction uncertainty caused by synergistic effects of biological, geochemical, and hydrological processes. The proposed approach successfully captured significant contributing factors across time and space, thereby improving the structure and parameterization of the comprehensive reactive-transport model. The global sensitivity analysis also provides a potentially useful tool to evaluate uranium bioremediation strategy. The simulations suggest that under difficult environments (e.g., highly contaminated with U(VI) at a high migration rate of solutes), the efficiency of uranium removal can be improved by adding Geobacter species to the contaminated site (bioaugmentation) in conjunction with the addition of electron donor (biostimulation). The simulations also highlight the interactive effect of

  14. Importance of organic amendment characteristics on bioremediation of PAH-contaminated soil.

    Science.gov (United States)

    Lukić, B; Huguenot, D; Panico, A; Fabbricino, M; van Hullebusch, E D; Esposito, G

    2016-08-01

    This study investigates the importance of the organic matter characteristics of several organic amendments (i.e., buffalo manure, food and kitchen waste, fruit and vegetables waste, and activated sewage sludge) and their influence in the bioremediation of a polycyclic aromatic hydrocarbons (PAH)-contaminated soil. The removal of low molecular weights (LMW) and high molecular weights (HMW) PAHs was monitored in four bioremediation reactors and used as an indicator of the role of organic amendments in contaminant removal. The total initial concentration of LMW PAHs was 234 mg kg(-1) soil (dry weight), while the amount for HMW PAHs was 422 mg kg(-1) soil (dry weight). Monitoring of operational parameters and chemical analysis was performed during 20 weeks. The concentrations of LMW PAH residues in soil were significantly lower in reactors that displayed a mesophilic phase, i.e., 11 and 15 %, compared to reactors that displayed a thermophilic phase, i.e., 29 and 31 %. Residual HMW PAHs were up to five times higher compared to residual LMW PAHs, depending on the reactor. This demonstrated that the amount of added organic matter and macronutrients such as nitrogen and phosphorus, the biochemical organic compound classes (mostly soluble fraction and proteins), and the operational temperature are important factors affecting the overall efficiency of bioremediation. On that basis, this study shows that characterization of biochemical families could contribute to a better understanding of the effects of organic amendments and clarify their different efficiency during a bioremediation process of PAH-contaminated soil.

  15. Bioremediation of soil polluted with crude oil and its derivatives: Microorganisms, degradation pathways, technologies

    OpenAIRE

    Beškoski Vladimir P.; Gojgić-Cvijović Gordana Đ.; Milić Jelena S.; Ilić Mila V.; Miletić Srđan B.; Jovančićević Branimir S.; Vrvić-Miroslav M.

    2012-01-01

    The contamination of soil and water with petroleum and its products occurs due to accidental spills during exploitation, transport, processing, storing and use. In order to control the environmental risks caused by petroleum products a variety of techniques based on physical, chemical and biological methods have been used. Biological methods are considered to have a comparative advantage as cost effective and environmentally friendly technologies. Bioremediation, defined as the use of b...

  16. ASSESSMENT OF DISTILLERY EFFLUENT IRRIGATION ON SOIL MICROBES AND ITS BIOREMEDIATION

    OpenAIRE

    Tripathi D. M; Tripathi S

    2014-01-01

    The present study deals with the assessment of toxicity of distillery effluent on soil microorganisms and its quality improvement through bioremediation using Pseudomonas spp. Under lab scale experiment, different dilutions of distillery effluent i.e. 25%, 50%, 75% were used to examine effects on physico-chemical parameters of effluent and on soil microflora e.g. algae, bacteria, fungi and actinomycetes. The results revealed that dilution may reduce significantly the metal contents and other...

  17. Isolation and Screening of Hydrocarbon Degrading Bacterial Strains for Bioremediation of Petroleum Pollution in Qatar

    OpenAIRE

    Al Disi, Zulfa Ali

    2013-01-01

    Pollution, due to activities related to the oil industry, represents a serious threat to the natural environment. The application of biotechnological methods provides much safer and sustainable alternatives for bioremediation of polluted areas, using microorganisms. Several techniques for the isolation of hydrocarbon degrading bacteria have been investigated and published worldwide. A wide range of bilogical activities was shown. However, local hydrocarbon degrading strains and the factors af...

  18. Bioremediation of Crude Oil Using Bacterium from the Coastal Sediments of Kish Island, Iran

    OpenAIRE

    SADEGHI HADDAD ZAVAREH, Maryam; Ebrahimipour, Gholamhossein; SHAHRIARI MOGHADAM, Mohsen; Fakhari, Javad; ABDOLI, Tahereh

    2016-01-01

    Background: Much of the environment is affected by petroleum contamination. It imposes serious health problems for humans as well as serious environmental impact. Bioremediation is an important consideration for removing environmental pollutants because, compared with other technologies, it incurrs lower costs and is environmentally compatible. Methods: Crude oil degrading bacteria were isolated using serial dilutions of a bacterial consortium. The Taguchi experimental design L16 (45) was use...

  19. Robust Hydrocarbon Degradation and Dynamics of Bacterial Communities during Nutrient-Enhanced Oil Spill Bioremediation

    OpenAIRE

    Röling, Wilfred F. M.; Milner, Michael G.; Jones, D. Martin; Lee, Kenneth; Daniel, Fabien; Swannell, Richard J. P.; Head, Ian M.

    2002-01-01

    Degradation of oil on beaches is, in general, limited by the supply of inorganic nutrients. In order to obtain a more systematic understanding of the effects of nutrient addition on oil spill bioremediation, beach sediment microcosms contaminated with oil were treated with different levels of inorganic nutrients. Oil biodegradation was assessed respirometrically and on the basis of changes in oil composition. Bacterial communities were compared by numerical analysis of denaturing gradient gel...

  20. Bioremediation of marine oil spills: when and when not – the Exxon Valdez experience

    OpenAIRE

    Atlas, Ronald; Bragg, James

    2009-01-01

    Summary In this article we consider what we have learned from the Exxon Valdez oil spill (EVOS) in terms of when bioremediation should be considered and what it can accomplish. We present data on the state of oiling of Prince William Sound shorelines 18 years after the spill, including the concentration and composition of subsurface oil residues (SSOR) sampled by systematic shoreline surveys conducted between 2002 and 2007. Over this period, 346 sediment samples were analysed by GC‐MS and ext...