WorldWideScience

Sample records for engineered microorganisms released

  1. Controlled field release of a bioluminescent genetically engineered microorganism for bioremediation process monitoring and control

    Energy Technology Data Exchange (ETDEWEB)

    Ripp, S.; Nivens, D.E.; Ahn, Y.; Werner, C.; Jarrell, J. IV; Easter, J.P.; Cox, C.D.; Burlage, R.S.; Sayler, G.S.

    2000-03-01

    Pseudomonas fluorescens HK44 represents the first genetically engineered microorganism approved for field testing in the United States for bioremediation purposes. Strain HK44 harbors an introduced lux gene fused within a naphthalene degradative pathway, thereby allowing this recombinant microbe to bioluminescent as it degrades specific polyaromatic hydrocarbons such as naphthalene. The bioremediation process can therefore be monitored by the detection of light. P. fluorescens HK44 was inoculated into the vadose zone of intermediate-scale, semicontained soil lysimeters contaminated with naphthalene, anthracene, and phenanthrene, and the population dynamics were followed over an approximate 2-year period in order to assess the long-term efficacy of using strain HK44 for monitoring and controlling bioremediation processes. Results showed that P. fluorescens HK44 was capable of surviving initial inoculation into both hydrocarbon contaminated and uncontaminated soils and was recoverable from these soils 660 days post inoculation. It was also demonstrated that strain HK44 was capable of generating bioluminescence in response to soil hydrocarbon bioavailability. Bioluminescence approaching 166,000 counts/s was detected in fiber optic-based biosensor devices responding to volatile polyaromatic hydrocarbons, while a portable photomultiplier module detected bioluminescence at an average of 4300 counts/s directly from soil-borne HK44 cells within localized treatment areas. The utilization of lux-based bioreporter microorganisms therefore promises to be a viable option for in situ determination of environmental contaminant bioavailability and biodegradation process monitoring and control.

  2. Engineering photosynthesis in plants and synthetic microorganisms.

    Science.gov (United States)

    Maurino, Veronica G; Weber, Andreas P M

    2013-01-01

    Photosynthetic organisms, such as cyanobacteria, algae, and plants, sustain life on earth by converting light energy, water, and CO(2) into chemical energy. However, due to global change and a growing human population, arable land is becoming scarce and resources, including water and fertilizers, are becoming exhausted. It will therefore be crucial to design innovative strategies for sustainable plant production to maintain the food and energy bases of human civilization. Several different strategies for engineering improved photosynthesis in crop plants and introducing novel photosynthetic capacity into microorganisms have been reviewed.

  3. Genetic engineering of microorganisms for biodiesel production

    Science.gov (United States)

    Lin, Hui; Wang, Qun; Shen, Qi; Zhan, Jumei; Zhao, Yuhua

    2013-01-01

    Biodiesel, as one type of renewable energy, is an ideal substitute for petroleum-based diesel fuel and is usually made from triacylglycerides by transesterification with alcohols. Biodiesel production based on microbial fermentation aiming to establish more efficient, less-cost and sustainable biodiesel production strategies is under current investigation by various start-up biotechnology companies and research centers. Genetic engineering plays a key role in the transformation of microbes into the desired cell factories with high efficiency of biodiesel production. Here, we present an overview of principal microorganisms used in the microbial biodiesel production and recent advances in metabolic engineering for the modification required. Overexpression or deletion of the related enzymes for de novo synthesis of biodiesel is highlighted with relevant examples. PMID:23222170

  4. Engineering of microorganisms towards recovery of rare metal ions

    Energy Technology Data Exchange (ETDEWEB)

    Kuroda, Kouichi; Ueda, Mitsuyoshi [Kyoto Univ. (Japan). Div. of Applied Life Sciences

    2010-06-15

    The bioadsorption of metal ions using microorganisms is an attractive technology for the recovery of rare metal ions as well as removal of toxic heavy metal ions from aqueous solution. In initial attempts, microorganisms with the ability to accumulate metal ions were isolated from nature and intracellular accumulation was enhanced by the overproduction of metal-binding proteins in the cytoplasm. As an alternative, the cell surface design of microorganisms by cell surface engineering is an emerging strategy for bioadsorption and recovery of metal ions. Cell surface engineering was firstly applied to the construction of a bioadsorbent to adsorb heavy metal ions for bioremediation. Cell surface adsorption of metal ions is rapid and reversible. Therefore, adsorbed metal ions can be easily recovered without cell breakage, and the bioadsorbent can be reused or regenerated. These advantages are suitable for the recovery of rare metal ions. Actually, the cell surface display of a molybdate-binding protein on yeast led to the enhanced adsorption of molybdate, one of the rare metal ions. An additional advantage is that the cell surface display system allows high-throughput screening of protein/peptide libraries owing to the direct evaluation of the displayed protein/peptide without purification and concentration. Therefore, the creation of novel metal-binding protein/ peptide and engineering of microorganisms towards the recovery of rare metal ions could be simultaneously achieved. (orig.)

  5. Evolutionary engineering of industrial microorganisms-strategies and applications.

    Science.gov (United States)

    Zhu, Zhengming; Zhang, Juan; Ji, Xiaomei; Fang, Zhen; Wu, Zhimeng; Chen, Jian; Du, Guocheng

    2018-06-01

    Microbial cells have been widely used in the industry to obtain various biochemical products, and evolutionary engineering is a common method in biological research to improve their traits, such as high environmental tolerance and improvement of product yield. To obtain better integrate functions of microbial cells, evolutionary engineering combined with other biotechnologies have attracted more attention in recent years. Classical laboratory evolution has been proven effective to letting more beneficial mutations occur in different genes but also has some inherent limitations such as a long evolutionary period and uncontrolled mutation frequencies. However, recent studies showed that some new strategies may gradually overcome these limitations. In this review, we summarize the evolutionary strategies commonly used in industrial microorganisms and discuss the combination of evolutionary engineering with other biotechnologies such as systems biology and inverse metabolic engineering. Finally, we prospect the importance and application prospect of evolutionary engineering as a powerful tool especially in optimization of industrial microbial cell factories.

  6. Metabolic Engineering of Microorganisms for the Production of Higher Alcohols

    Science.gov (United States)

    Choi, Yong Jun; Lee, Joungmin; Jang, Yu-Sin

    2014-01-01

    ABSTRACT Due to the increasing concerns about limited fossil resources and environmental problems, there has been much interest in developing biofuels from renewable biomass. Ethanol is currently used as a major biofuel, as it can be easily produced by existing fermentation technology, but it is not the best biofuel due to its low energy density, high vapor pressure, hygroscopy, and incompatibility with current infrastructure. Higher alcohols, including 1-propanol, 1-butanol, isobutanol, 2-methyl-1-butanol, and 3-methyl-1-butanol, which possess fuel properties more similar to those of petroleum-based fuel, have attracted particular interest as alternatives to ethanol. Since microorganisms isolated from nature do not allow production of these alcohols at high enough efficiencies, metabolic engineering has been employed to enhance their production. Here, we review recent advances in metabolic engineering of microorganisms for the production of higher alcohols. PMID:25182323

  7. Advancing metabolic engineering through systems biology of industrial microorganisms.

    Science.gov (United States)

    Dai, Zongjie; Nielsen, Jens

    2015-12-01

    Development of sustainable processes to produce bio-based compounds is necessary due to the severe environmental problems caused by the use of fossil resources. Metabolic engineering can facilitate the development of highly efficient cell factories to produce these compounds from renewable resources. The objective of systems biology is to gain a comprehensive and quantitative understanding of living cells and can hereby enhance our ability to characterize and predict cellular behavior. Systems biology of industrial microorganisms is therefore valuable for metabolic engineering. Here we review the application of systems biology tools for the identification of metabolic engineering targets which may lead to reduced development time for efficient cell factories. Finally, we present some perspectives of systems biology for advancing metabolic engineering further. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Advancing metabolic engineering through systems biology of industrial microorganisms

    DEFF Research Database (Denmark)

    Dai, Zongjie; Nielsen, Jens

    2015-01-01

    resources. The objective of systems biology is to gain a comprehensive and quantitative understanding of living cells and can hereby enhance our ability to characterize and predict cellular behavior. Systems biology of industrial microorganisms is therefore valuable for metabolic engineering. Here we review......Development of sustainable processes to produce bio-based compounds is necessary due to the severe environmental problems caused by the use of fossil resources. Metabolic engineering can facilitate the development of highly efficient cell factories to produce these compounds from renewable...... the application of systems biology tools for the identification of metabolic engineering targets which may lead to reduced development time for efficient cell factories. Finally, we present some perspectives of systems biology for advancing metabolic engineering further....

  9. Controlled drug release for tissue engineering.

    Science.gov (United States)

    Rambhia, Kunal J; Ma, Peter X

    2015-12-10

    Tissue engineering is often referred to as a three-pronged discipline, with each prong corresponding to 1) a 3D material matrix (scaffold), 2) drugs that act on molecular signaling, and 3) regenerative living cells. Herein we focus on reviewing advances in controlled release of drugs from tissue engineering platforms. This review addresses advances in hydrogels and porous scaffolds that are synthesized from natural materials and synthetic polymers for the purposes of controlled release in tissue engineering. We pay special attention to efforts to reduce the burst release effect and to provide sustained and long-term release. Finally, novel approaches to controlled release are described, including devices that allow for pulsatile and sequential delivery. In addition to recent advances, limitations of current approaches and areas of further research are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Effect of Microorganisms in the Bioremediation of Spent Engine Oil ...

    African Journals Online (AJOL)

    ADOWIE PERE

    interaction of these factors as suitable conditions are provided (Rahman et al., ... Magnesium, Copper, Zinc, Lead, Cadmium and so on from the wear and tear of the ..... microorganisms would also require essential nutrients as hydrocarbons ...

  11. Biobased production of alkanes and alkenes through metabolic engineering of microorganisms

    OpenAIRE

    Kang, Min Kyoung; Nielsen, Jens

    2017-01-01

    Advancement in metabolic engineering of microorganisms has enabled bio-based production of a range of chemicals, and such engineered microorganism can be used for sustainable production leading to reduced carbon dioxide emission there. One area that has attained much interest is microbial hydrocarbon biosynthesis, and in particular, alkanes and alkenes are important high-value chemicals as they can be utilized for a broad range of industrial purposes as well as ?drop-in? biofuels. Some microo...

  12. Cell surface engineering of industrial microorganisms for biorefining applications.

    Science.gov (United States)

    Tanaka, Tsutomu; Kondo, Akihiko

    2015-11-15

    In order to decrease carbon emissions and negative environmental impacts of various pollutants, biofuel/biochemical production should be promoted for replacing fossil-based industrial processes. Utilization of abundant lignocellulosic biomass as a feedstock has recently become an attractive option. In this review, we focus on recent efforts of cell surface display using industrial microorganisms such as Escherichia coli and yeast. Cell surface display is used primarily for endowing cellulolytic activity on the host cells, and enables direct fermentation to generate useful fuels and chemicals from lignocellulosic biomass. Cell surface display systems are systematically summarized, and the drawbacks/perspectives as well as successful application of surface display for industrial biotechnology are discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Biobased production of alkanes and alkenes through metabolic engineering of microorganisms

    DEFF Research Database (Denmark)

    Kang, Min Kyoung; Nielsen, Jens

    2017-01-01

    Advancement in metabolic engineering of microorganisms has enabled bio-based production of a range of chemicals, and such engineered microorganism can be used for sustainable production leading to reduced carbon dioxide emission there. One area that has attained much interest is microbial...... hydrocarbon biosynthesis, and in particular, alkanes and alkenes are important high-value chemicals as they can be utilized for a broad range of industrial purposes as well as ‘drop-in’ biofuels. Some microorganisms have the ability to biosynthesize alkanes and alkenes naturally, but their production level...... is extremely low. Therefore, there have been various attempts to recruit other microbial cell factories for production of alkanes and alkenes by applying metabolic engineering strategies. Here we review different pathways and involved enzymes for alkane and alkene production and discuss bottlenecks...

  14. Regulatory RNA-assisted genome engineering in microorganisms.

    Science.gov (United States)

    Si, Tong; HamediRad, Mohammad; Zhao, Huimin

    2015-12-01

    Regulatory RNAs are increasingly recognized and utilized as key modulators of gene expression in diverse organisms. Thanks to their modular and programmable nature, trans-acting regulatory RNAs are especially attractive in genome-scale applications. Here we discuss the recent examples in microbial genome engineering implementing various trans-acting RNA platforms, including sRNA, RNAi, asRNA and CRISRP-Cas. In particular, we focus on how the scalable and multiplex nature of trans-acting RNAs has been used to tackle the challenges in creating genome-wide and combinatorial diversity for functional genomics and metabolic engineering applications. Advances in computational design and context-dependent regulation are also discussed for their contribution in improving fine-tuning capabilities of trans-acting RNAs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Cell surface engineering of microorganisms towards adsorption of heavy metals.

    Science.gov (United States)

    Li, Peng-Song; Tao, Hu-Chun

    2015-06-01

    Heavy metal contamination has become a worldwide environmental concern due to its toxicity, non-degradability and food-chain bioaccumulation. Conventional physical and chemical treatment methods for heavy metal removal have disadvantages such as cost-intensiveness, incomplete removal, secondary pollution and the lack of metal specificity. Microbial biomass-based biosorption is one of the approaches gaining increasing attention because it is effective, cheap, and environmental friendly and can work well at low concentrations. To enhance the adsorption properties of microbial cells to heavy metal ions, the cell surface display of various metal-binding proteins/peptides have been performed using a cell surface engineering approach. The surface engineering of Gram-negative bacteria, Gram-positive bacteria and yeast towards the adsorption of heavy metals are reviewed in this article. The problems and future perspectives of this technology are discussed.

  16. Production of anthocyanins in metabolically engineered microorganisms: Current status and perspectives

    Directory of Open Access Journals (Sweden)

    Jian Zha

    2017-12-01

    Full Text Available Microbial production of plant-derived natural products by engineered microorganisms has achieved great success thanks to large extend to metabolic engineering and synthetic biology. Anthocyanins, the water-soluble colored pigments found in terrestrial plants that are responsible for the red, blue and purple coloration of many flowers and fruits, are extensively used in food and cosmetics industry; however, their current supply heavily relies on complex extraction from plant-based materials. A promising alternative is their sustainable production in metabolically engineered microbes. Here, we review the recent progress on anthocyanin biosynthesis in engineered bacteria, with a special focus on the systematic engineering modifications such as selection and engineering of biosynthetic enzymes, engineering of transportation, regulation of UDP-glucose supply, as well as process optimization. These promising engineering strategies will facilitate successful microbial production of anthocyanins in industry in the near future.

  17. Biobased organic acids production by metabolically engineered microorganisms

    DEFF Research Database (Denmark)

    Chen, Yun; Nielsen, Jens

    2016-01-01

    Bio-based production of organic acids via microbial fermentation has been traditionally used in food industry. With the recent desire to develop more sustainable bioprocesses for production of fuels, chemicals and materials, the market for microbial production of organic acids has been further...... expanded as organic acids constitute a key group among top building block chemicals that can be produced from renewable resources. Here we review the current status for production of citric acid and lactic acid, and we highlight the use of modern metabolic engineering technologies to develop high...... performance microbes for production of succinic acid and 3-hydroxypropionic acid. Also, the key limitations and challenges in microbial organic acids production are discussed...

  18. Evaluation of terrestrial microcosms for assessing the fate and effects of genetically engineered microorganisms on ecological processes

    Energy Technology Data Exchange (ETDEWEB)

    Fredrickson, J.K.; Bentjen, S.A.; Bolton, H. Jr.; Li, S.W.; Ligotke, M.W.; McFadden, K.M.; Van Voris, P.

    1989-04-01

    This project evaluates and modifies the existing US Environmental Protection Agency's Office of Pesticides and Toxic Substances (EPA/OPTS) terrestrial microcosm test system and test protocols such that they can be used to determine the environmental fate and ecological hazards of genetically engineered microorganisms (GEMs). The intact soil-core microcosm represents terrestrial ecosystems, and when coupled with appropriate test protocols, such microcosms may be appropriate to define and limit risks associated with the intentional release of GEMs. The terrestrial microcosm test system was used to investigate the survival and transport of two model GEMs (Azospirillum lipoferum and Pseudomonas sp. Tn5 mutants) to various trophic levels and niches and through intact soil cores. Subsequent effects on nutrient cycling and displacement of indigenous microorganisms were evaluated. The model organisms were a diazotrophic root-colonizing bacterium (A. lipoferum) and a wheat root growth-inhibiting rhizobacterium (Pseudomonas sp.). The transposable element Tn5 was used as a genetic marker for both microorganisms in two separate experiments. The organisms were subjected to transposon mutagenesis using a broad host-range-mobilizable suicide plasmid. The transposon Tn5 conferred levels of kanamycin resistance up to 500 ..mu..g/ml (Pseudomonas sp.), which allowed for selection of the bacteria from environmental samples. The presence of Tn5 DNA in the genome of the model GEMs also allowed the use of Tn5 gene probes to confirm and enumerate the microorganisms in different samples from the microcosms. Two types of root growth-inhibiting Pseudomonas sp. Tn5 mutants were obtained and used in microcosm studies: those that lacked the ability to inhibit either wheat root growth or the growth of other microorganisms in vitro (tox/sup /minus//) and those which retained these properties (tox/sup +/). 53 refs., 7 figs., 6 tabs.

  19. Metabolic engineering of microorganisms for biofuels production: from bugs to synthetic biology to fuels

    Energy Technology Data Exchange (ETDEWEB)

    Kuk Lee, Sung; Chou, Howard; Ham, Timothy S.; Soon Lee, Taek; Keasling, Jay D.

    2009-12-02

    The ability to generate microorganisms that can produce biofuels similar to petroleum-based transportation fuels would allow the use of existing engines and infrastructure and would save an enormous amount of capital required for replacing the current infrastructure to accommodate biofuels that have properties significantly different from petroleum-based fuels. Several groups have demonstrated the feasibility of manipulating microbes to produce molecules similar to petroleum-derived products, albeit at relatively low productivity (e.g. maximum butanol production is around 20 g/L). For cost-effective production of biofuels, the fuel-producing hosts and pathways must be engineered and optimized. Advances in metabolic engineering and synthetic biology will provide new tools for metabolic engineers to better understand how to rewire the cell in order to create the desired phenotypes for the production of economically viable biofuels.

  20. Redox cofactor engineering in industrial microorganisms: strategies, recent applications and future directions.

    Science.gov (United States)

    Liu, Jiaheng; Li, Huiling; Zhao, Guangrong; Caiyin, Qinggele; Qiao, Jianjun

    2018-05-01

    NAD and NADP, a pivotal class of cofactors, which function as essential electron donors or acceptors in all biological organisms, drive considerable catabolic and anabolic reactions. Furthermore, they play critical roles in maintaining intracellular redox homeostasis. However, many metabolic engineering efforts in industrial microorganisms towards modification or introduction of metabolic pathways, especially those involving consumption, generation or transformation of NAD/NADP, often induce fluctuations in redox state, which dramatically impede cellular metabolism, resulting in decreased growth performance and biosynthetic capacity. Here, we comprehensively review the cofactor engineering strategies for solving the problematic redox imbalance in metabolism modification, as well as their features, suitabilities and recent applications. Some representative examples of in vitro biocatalysis are also described. In addition, we briefly discuss how tools and methods from the field of synthetic biology can be applied for cofactor engineering. Finally, future directions and challenges for development of cofactor redox engineering are presented.

  1. [Effect of the interaction of microorganisms and iron oxides on arsenic releasing into groundwater in Chinese Loess].

    Science.gov (United States)

    Xie, Yun-Yun; Chen, Tian-Hu; Zhou, Yue-Fei; Xie, Qiao-Qin

    2013-10-01

    A large part of groundwater in the Chinese Loess Plateau area is characterized by high arsenic concentration. Anaerobic bacteria have been considered to play key roles in promoting arsenic releasing from loess to groundwater. However, this hypothesis remains unconfirmed. Based on modeling experiments, this study investigated the speciation of arsenic in loess, and then determined the release rates and quantities of arsenic with the mediation of anaerobic bacteria. The results showed that arsenic contents in loess were between 23 mg.kg-1 and 30 mg.kg-1. No obvious arsenic content difference among loess samples was observed. The ratios for specific adsorbed, iron oxides co-precipitated and silicate co-precipitated arsenic were 37.76% , 36. 15% and 25. 69% , respectively. Indigenous microorganisms, dissimilatory iron reducing bacteria (DIRB) and sulfate reducing bacteria (SRB) could all promote the release of arsenic from loess. Organic matters highly affected the release rates. More than 100 mg.L-1 sodium lactate was required for all bacterial experiments to facilitate obvious arsenic release. Considering the redox condition in loess, the contribution of SRB to arsenic release in loess area was less feasible than that of DIRB and indigenous microorganisms.

  2. 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.

  3. Release, transport and toxicity of engineered nanoparticles.

    Science.gov (United States)

    Soni, Deepika; Naoghare, Pravin K; Saravanadevi, Sivanesan; Pandey, Ram Avatar

    2015-01-01

    Recent developments in nanotechnology have facilitated the synthesis of novel engineered nanoparticles (ENPs) that possess new and different physicochemical properties. These ENPs have been ex tensive ly used in various commercial sectors to achieve both social and economic benefits. However. the increasing production and consumption of ENPs by many different industries has raised concerns about their possible release and accumulation in the environment. Released EN Ps may either remain suspended in the atmosphere for several years or may accumulate and eventually be modified int o other substances. Settled nanoparticles can he easily washed away during ra in s. and therefore may easily enter the food chain via water and so il. Thus. EN Ps can contaminate air. water and soil and can subsequently pose adverse risks to the health of different organisms. Studies to date indicate that ENP transport to and within the ecosystem depend on their chemical and physical properties (viz .. size. shape and solubility) . Therefore. the EN Ps display variable behavior in the environment because of their individual properties th at affect their tendency for adsorption, absorption, diffusional and colloidal interaction. The transport of EN Ps also influences their fate and chemical transformation in ecosystems. The adsorption, absorption and colloidal interaction of ENPs affect their capacity to be degraded or transformed, whereas the tendency of ENPs to agglomerate fosters their sedimentation. How widely ENPs are transported and their environmental fate influence how tox ic they may become to environmental organisms. One barrier to fully understanding how EN Ps are transformed in the environment and how best to characterize their toxicity, is related to the nature of their ultrafine structure. Experiments with different animals, pl ants, and cell lines have revealed that ENPs induce toxicity via several cellular pathways that is linked to the size. shape. surface area

  4. Global life cycle releases of engineered nanomaterials

    International Nuclear Information System (INIS)

    Keller, Arturo A.; McFerran, Suzanne; Lazareva, Anastasiya; Suh, Sangwon

    2013-01-01

    Engineered nanomaterials (ENMs) are now becoming a significant fraction of the material flows in the global economy. We are already reaping the benefits of improved energy efficiency, material use reduction, and better performance in many existing and new applications that have been enabled by these technological advances. As ENMs pervade the global economy, however, it becomes important to understand their environmental implications. As a first step, we combined ENM market information and material flow modeling to produce the first global assessment of the likely ENM emissions to the environment and landfills. The top ten most produced ENMs by mass were analyzed in a dozen major applications. Emissions during the manufacturing, use, and disposal stages were estimated, including intermediate steps through wastewater treatment plants and waste incineration plants. In 2010, silica, titania, alumina, and iron and zinc oxides dominate the ENM market in terms of mass flow through the global economy, used mostly in coatings/paints/pigments, electronics and optics, cosmetics, energy and environmental applications, and as catalysts. We estimate that 63–91 % of over 260,000–309,000 metric tons of global ENM production in 2010 ended up in landfills, with the balance released into soils (8–28 %), water bodies (0.4–7 %), and atmosphere (0.1–1.5 %). While there are considerable uncertainties in the estimates, the framework for estimating emissions can be easily improved as better data become available. The material flow estimates can be used to quantify emissions at the local level, as inputs for fate and transport models to estimate concentrations in different environmental compartments.

  5. Extremely Thermophilic Microorganisms as Metabolic Engineering Platforms for Production of Fuels and Industrial Chemicals

    Directory of Open Access Journals (Sweden)

    Benjamin M Zeldes

    2015-11-01

    Full Text Available Enzymes from extremely thermophilic microorganisms have been of technological interest for some time because of their ability to catalyze reactions of industrial significance at elevated temperatures. Thermophilic enzymes are now routinely produced in recombinant mesophilic hosts for use as discrete biocatalysts. Genome and metagenome sequence data for extreme thermophiles provide useful information for putative biocatalysts for a wide range of biotransformations, albeit involving at most a few enzymatic steps. However, in the past several years, unprecedented progress has been made in establishing molecular genetics tools for extreme thermophiles to the point that the use of these microorganisms as metabolic engineering platforms has become possible. While in its early days, complex metabolic pathways have been altered or engineered into recombinant extreme thermophiles, such that the production of fuels and chemicals at elevated temperatures has become possible. Not only does this expand the thermal range for industrial biotechnology, it also potentially provides biodiverse options for specific biotransformations unique to these microorganisms. The list of extreme thermophiles growing optimally between 70 and 100°C with genetic toolkits currently available includes archaea and bacteria, aerobes and anaerobes, coming from genera such as Caldicellulosiruptor, Sulfolobus, Thermotoga, Thermococcus and Pyrococcus. These organisms exhibit unusual and potentially useful native metabolic capabilities, including cellulose degradation, metal solubilization, and RuBisCO-free carbon fixation. Those looking to design a thermal bioprocess now have a host of potential candidates to choose from, each with its own advantages and challenges that will influence its appropriateness for specific applications. Here, the issues and opportunities for extremely thermophilic metabolic engineering platforms are considered with an eye towards potential technological

  6. Extremely thermophilic microorganisms as metabolic engineering platforms for production of fuels and industrial chemicals

    Science.gov (United States)

    Zeldes, Benjamin M.; Keller, Matthew W.; Loder, Andrew J.; Straub, Christopher T.; Adams, Michael W. W.; Kelly, Robert M.

    2015-01-01

    Enzymes from extremely thermophilic microorganisms have been of technological interest for some time because of their ability to catalyze reactions of industrial significance at elevated temperatures. Thermophilic enzymes are now routinely produced in recombinant mesophilic hosts for use as discrete biocatalysts. Genome and metagenome sequence data for extreme thermophiles provide useful information for putative biocatalysts for a wide range of biotransformations, albeit involving at most a few enzymatic steps. However, in the past several years, unprecedented progress has been made in establishing molecular genetics tools for extreme thermophiles to the point that the use of these microorganisms as metabolic engineering platforms has become possible. While in its early days, complex metabolic pathways have been altered or engineered into recombinant extreme thermophiles, such that the production of fuels and chemicals at elevated temperatures has become possible. Not only does this expand the thermal range for industrial biotechnology, it also potentially provides biodiverse options for specific biotransformations unique to these microorganisms. The list of extreme thermophiles growing optimally between 70 and 100°C with genetic toolkits currently available includes archaea and bacteria, aerobes and anaerobes, coming from genera such as Caldicellulosiruptor, Sulfolobus, Thermotoga, Thermococcus, and Pyrococcus. These organisms exhibit unusual and potentially useful native metabolic capabilities, including cellulose degradation, metal solubilization, and RuBisCO-free carbon fixation. Those looking to design a thermal bioprocess now have a host of potential candidates to choose from, each with its own advantages and challenges that will influence its appropriateness for specific applications. Here, the issues and opportunities for extremely thermophilic metabolic engineering platforms are considered with an eye toward potential technological advantages for high

  7. DEVELOPMENT OF MICROORGANISMS FOR CELLULOSE-BIOFUEL CONSOLIDATED BIOPROCESSINGS: METABOLIC ENGINEERS' TRICKS

    Directory of Open Access Journals (Sweden)

    Roberto Mazzoli

    2012-10-01

    By starting from the description of natural enzyme systems for plant biomass degradation and natural metabolic pathways for some of the most valuable product (i.e. butanol, ethanol, and hydrogen biosynthesis, this review describes state-of-the-art bottlenecks and solutions for the development of recombinant microbial strains for cellulosic biofuel CBP by metabolic engineering. Complexed cellulases (i.e. cellulosomes benefit from stronger proximity effects and show enhanced synergy on insoluble substrates (i.e. crystalline cellulose with respect to free enzymes. For this reason, special attention was held on strategies involving cellulosome/designer cellulosome-bearing recombinant microorganisms.

  8. A self-referential HOWTO on release engineering

    Energy Technology Data Exchange (ETDEWEB)

    Galassi, Mark C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-01-31

    Release engineering is a fundamental part of the software development cycle: it is the point at which quality control is exercised and bug fixes are integrated. The way in which software is released also gives the end user her first experience of a software package, while in scientific computing release engineering can guarantee reproducibility. For these reasons and others, the release process is a good indicator of the maturity and organization of a development team. Software teams often do not put in place a release process at the beginning. This is unfortunate because the team does not have early and continuous execution of test suites, and it does not exercise the software in the same conditions as the end users. I describe an approach to release engineering based on the software tools developed and used by the GNU project, together with several specific proposals related to packaging and distribution. I do this in a step-by-step manner, demonstrating how this very paper is written and built using proper release engineering methods. Because many aspects of release engineering are not exercised in the building of the paper, the accompanying software repository also contains examples of software libraries.

  9. Evaluation of terrestrial microcosms for detection, fate, and survival analysis of genetically engineered microorganisms and their recombinant genetic material

    Energy Technology Data Exchange (ETDEWEB)

    Fredrickson, J.K.; Seidler, R.J.

    1989-02-01

    The research included in this document represents the current scientific information available regarding the applicability of terrestrial microcosms and related methodologies for evaluating detection methods and the fate and survival of microorganisms in the environment. The three terrestrial microcosms described in this document were used to evaluate the survival and fate of recombinant bacteria in soils and in association with plant surfaces and insects and their transport through soil with percolating water and root systems, and to test new methods and procedures to improve detection and enumeration of bacteria in soil. Simple (potting soil composed of peat mix and perlite, lacking environmental control and monitoring) and complex microcosms (agricultural soil with partial control and monitoring of environmental conditions) were demonstrated to be useful tools for preliminary assessments of microbial viability in terrestrial ecosystems. These studies evaluated the survival patterns of Enterobacter cloacae (pBR322) in soil and on plant surfaces and the ingestion of this same microorganism by cutworms and survival in the foregut and frass. The Versacore microcosm design was used to monitor the fate and competitiveness of genetically engineered bacteria in soil. Both selective media and gene probes were used successfully to follow the fate of two recombinant Pseudomonas sp. introduced into Versacore microcosms. Intact soil-core microcosms were employed to evaluate the fate and transport of genetically altered Azospirillum sp. and Pseudomonas sp. in soil and the plant rhizosphere. The usefulness of these various microcosms as a tool for risk assessment is underscored by the ease in obtaining soil from a proposed field release site to evaluate subsequent GEM fate and survival.

  10. Idaho National Engineering Laboratory release criteria for decontamination and decommissioning

    International Nuclear Information System (INIS)

    Dolenc, M.R.; Case, M.J.

    1986-01-01

    Criteria have been developed for release of Idaho National Engineering Laboratory (INEL) facilities and land areas following decontamination and decommissioning (D and D). Decommissioning release criteria in the form of dose guidelines were proposed by the US Nuclear Regulatory Commission as early as 1980. These criteria were used on an interim basis for INEL D and D projects. However, dose guidelines alone do not adequately cover the criteria necessary to release sites for unrestricted use. In actual practice, other parameters such as pathways analyses, sampling and instrumentation techniques, and implementation procedures are required to develop the basis for unrestricted release of a site. Thus, a rigorous approach for evaluating these other parameters is needed to develop acceptable D and D release criteria. Because of the complex and sensitive nature of the dose and pathways analyses work, a thorough review by experts in those respective fields was desired. Input and support in preparing or reviewing each part of the criteria development task was solicited from several DOE field offices. Experts were identified and contracted to assist in preparing portions of the release criteria, or to serve on a peer-review committee. Thus, the entire release criteria development task was thoroughly reviewed by recognized experts from each DOE field office, to validate technical content of the INEL site-specific document

  11. Application of genetically engineered microorganisms to bioremediation and wastewater treatment. Idenshi sosa biseibutsu no kankyo joka mizushori eno tekiyo

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, M; Ike, M [Osaka University, Osaka (Japan). Faculty of Engineering

    1993-11-10

    This paper summarizes the following techniques: a gene engineering method for bioremediation and wastewater treatment, microorganism breeding using the former method, and a monitoring technique for genetical and ecological stability of genetically engineered microorganisms. Recombination bacteria reinforced with PH genes showed higher phenol removing rate than wild strains, but presented accumulation of catechol in such a large quantity as cannot be seen in wild strains, with the complete degradation rate rather decreased. Gene recombined bacteria structured by introducing the recombined plasmid, pBH500, had high genetic stability when P.putida BH-1 is used as a host. E.coli C600 having recombined plasmid and P.putida BH were added and cultivated in activated sludge. As a result, both recombined bacteria showed rapid logarithmic decrease just after the addition, then, maintained the relatively stable population groups, and remained in the activated sludge for an extended period of time. In monitoring techniques, the colony hybridization process detected clearly the gene recombined bacteria. 9 refs., 7 figs., 1 tab.

  12. Persistance of a surrogate for a genetically engineered cellulolytic microorganism and effects on aquatic community and ecosystem properties: Mesocosm and stream comparisons

    International Nuclear Information System (INIS)

    Bott, T.L.; Kaplan, L.A.

    1993-01-01

    The accidental or deliberate release of genetically engineered microorganisms (GEMs) into the environment raises concerns related to their potential to alter natural processes and biological communities. Research was conducted to determine the persistance of an introduced surrogate for a GEM in lotic habitats, to test the responses to the introduced bacterial, and to evaluate the utility of flowing water mesocosms as tools for assessing the fates and effects of bacteria introduced into streams. Cellulolomonas cellulose-degrading bacteria were selcted as the GEM surrogate because cellulose superdegrader bacteria are being genetically engineered and are of interest to the food and paper industries and in the conversion of biomass to fuels. Cellulomonas densities were determined using fluorescent antibodies, and declined from postinoculation maxima faster in sediments than in Chlorophyta growths and leaf packs. Cellulomonas persisted in leaf packs at densities much greater than background. Cellulomonas had no statistically significant effects on primary productivity, community respiration, photosynthesis/respiration ratios, assimilation ratios, bacterial productivity, and rates of leaf litter decomposition. Cellulase concentrations were positively correlated with Cellulolomonas densities ≥7x10 8 cells/g dry mass in fresh leaf litter for 2 d following exposure. Mesocosms were good tools for studying bacterial population dynamics in leaf litter and physiological aspects of litter degradation. 45 refs., 8 figs., 5 tabs

  13. Protein engineering in designing tailored enzymes and microorganisms for biofuels production

    Science.gov (United States)

    Wen, Fei; Nair, Nikhil U; Zhao, Huimin

    2009-01-01

    Summary Lignocellulosic biofuels represent a sustainable, renewable, and the only foreseeable alternative energy source to transportation fossil fuels. However, the recalcitrant nature of lignocellulose poses technical hurdles to an economically viable biorefinery. Low enzymatic hydrolysis efficiency and low productivity, yield, and titer of biofuels are among the top cost contributors. Protein engineering has been used to improve the performances of lignocellulose-degrading enzymes, as well as proteins involved in biofuel synthesis pathways. Unlike its great success seen in other industrial applications, protein engineering has achieved only modest results in improving the lignocellulose-to-biofuels efficiency. This review will discuss the unique challenges that protein engineering faces in the process of converting lignocellulose to biofuels and how they are addressed by recent advances in this field. PMID:19660930

  14. Microorganism immobilization

    Science.gov (United States)

    Compere, Alicia L.; Griffith, William L.

    1981-01-01

    Live metabolically active microorganisms are immobilized on a solid support by contacting particles of aggregate material with a water dispersible polyelectrolyte such as gelatin, crosslinking the polyelectrolyte by reacting it with a crosslinking agent such as glutaraldehyde to provide a crosslinked coating on the particles of aggregate material, contacting the coated particles with live microorganisms and incubating the microorganisms in contact with the crosslinked coating to provide a coating of metabolically active microorganisms. The immobilized microorganisms have continued growth and reproduction functions.

  15. Impact of Dissociation and Sensible Heat Release on Pulse Detonation and Gas Turbine Engine Performance

    Science.gov (United States)

    Povinelli, Louis A.

    2001-01-01

    A thermodynamic cycle analysis of the effect of sensible heat release on the relative performance of pulse detonation and gas turbine engines is presented. Dissociation losses in the PDE (Pulse Detonation Engine) are found to cause a substantial decrease in engine performance parameters.

  16. Fuel effects on knock, heat releases and CARS temperatures in a spark ignition engine

    NARCIS (Netherlands)

    Kalghatgi, G.T.; Golombok, M.; Snowdon, P.

    1995-01-01

    Net heat release, knock characteristics and temperature were derived from in-cylinder pressure and end-gas CARS measurements for different fuels in a single-cylinder engine. The maximum net heat release rate resulting from the final phase of autoignition is closely associated with knock intensity.

  17. Method for the production of l-serine using genetically engineered microorganisms deficient in serine degradation pathways

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention generally relates to the microbiological industry, and specifically to the production of L-serine using genetically modified bacteria. The present invention provides genetically modified microorganisms, such as bacteria, wherein the expression of genes encoding for enzymes...... concentrations of serine. The present invention also provides methods for the production of L-serine or L-serine derivative using such genetically modified microorganisms....

  18. A new mechanistic and engineering fission gas release model for a uranium dioxide fuel

    International Nuclear Information System (INIS)

    Lee, Chan Bock; Yang, Yong Sik; Kim, Dae Ho; Kim, Sun Ki; Bang, Je Geun

    2008-01-01

    A mechanistic and engineering fission gas release model (MEGA) for uranium dioxide (UO 2 ) fuel was developed. It was based upon the diffusional release of fission gases from inside the grain to the grain boundary and the release of fission gases from the grain boundary to the external surface by the interconnection of the fission gas bubbles in the grain boundary. The capability of the MEGA model was validated by a comparison with the fission gas release data base and the sensitivity analyses of the parameters. It was found that the MEGA model correctly predicts the fission gas release in the broad range of fuel burnups up to 98 MWd/kgU. Especially, the enhancement of fission gas release in a high-burnup fuel, and the reduction of fission gas release at a high burnup by increasing the UO 2 grain size were found to be correctly predicted by the MEGA model without using any artificial factor. (author)

  19. Micro-Organ Device

    Science.gov (United States)

    Gonda, Steve R. (Inventor); Chang, Robert C. (Inventor); Starly, Binil (Inventor); Culbertson, Christopher (Inventor); Holtorf, Heidi L. (Inventor); Sun, Wei (Inventor); Leslie, Julia (Inventor)

    2013-01-01

    A method for fabricating a micro-organ device comprises providing a microscale support having one or more microfluidic channels and one or more micro-chambers for housing a micro-organ and printing a micro-organ on the microscale support using a cell suspension in a syringe controlled by a computer-aided tissue engineering system, wherein the cell suspension comprises cells suspended in a solution containing a material that functions as a three-dimensional scaffold. The printing is performed with the computer-aided tissue engineering system according to a particular pattern. The micro-organ device comprises at least one micro-chamber each housing a micro-organ; and at least one microfluidic channel connected to the micro-chamber, wherein the micro-organ comprises cells arranged in a configuration that includes microscale spacing between portions of the cells to facilitate diffusion exchange between the cells and a medium supplied from the at least one microfluidic channel.

  20. Mimicking Neurotransmitter Release in Chemical Synapses via Hysteresis Engineering in MoS2 Transistors.

    Science.gov (United States)

    Arnold, Andrew J; Razavieh, Ali; Nasr, Joseph R; Schulman, Daniel S; Eichfeld, Chad M; Das, Saptarshi

    2017-03-28

    Neurotransmitter release in chemical synapses is fundamental to diverse brain functions such as motor action, learning, cognition, emotion, perception, and consciousness. Moreover, improper functioning or abnormal release of neurotransmitter is associated with numerous neurological disorders such as epilepsy, sclerosis, schizophrenia, Alzheimer's disease, and Parkinson's disease. We have utilized hysteresis engineering in a back-gated MoS 2 field effect transistor (FET) in order to mimic such neurotransmitter release dynamics in chemical synapses. All three essential features, i.e., quantal, stochastic, and excitatory or inhibitory nature of neurotransmitter release, were accurately captured in our experimental demonstration. We also mimicked an important phenomenon called long-term potentiation (LTP), which forms the basis of human memory. Finally, we demonstrated how to engineer the LTP time by operating the MoS 2 FET in different regimes. Our findings could provide a critical component toward the design of next-generation smart and intelligent human-like machines and human-machine interfaces.

  1. Dynamic Model for the Stocks and Release Flows of Engineered Nanomaterials.

    Science.gov (United States)

    Song, Runsheng; Qin, Yuwei; Suh, Sangwon; Keller, Arturo A

    2017-11-07

    Most existing life-cycle release models for engineered nanomaterials (ENM) are static, ignoring the dynamics of stock and flows of ENMs. Our model, nanoRelease, estimates the annual releases of ENMs from manufacturing, use, and disposal of a product explicitly taking stock and flow dynamics into account. Given the variabilities in key parameters (e.g., service life of products and annual release rate during use) nanoRelease is designed as a stochastic model. We apply nanoRelease to three ENMs (TiO 2 , SiO 2 and FeO x ) used in paints and coatings through seven product applications, including construction and building, household and furniture, and automotive for the period from 2000 to 2020 using production volume and market projection information. We also consider model uncertainties using Monte Carlo simulation. Compared with 2016, the total annual releases of ENMs in 2020 will increase by 34-40%, and the stock will increase by 28-34%. The fraction of the end-of-life release among total release flows will increase from 11% in 2002 to 43% in 2020. As compared to static models, our dynamic model predicts about an order of magnitude lower values for the amount of ENM released from this sector in the near-term while stock continues to build up in the system.

  2. Prediction and Validation of Heat Release Direct Injection Diesel Engine Using Multi-Zone Model

    Science.gov (United States)

    Anang Nugroho, Bagus; Sugiarto, Bambang; Prawoto; Shalahuddin, Lukman

    2014-04-01

    The objective of this study is to develop simulation model which capable to predict heat release of diesel combustion accurately in efficient computation time. A multi-zone packet model has been applied to solve the combustion phenomena inside diesel cylinder. The model formulations are presented first and then the numerical results are validated on a single cylinder direct injection diesel engine at various engine speed and timing injections. The model were found to be promising to fulfill the objective above.

  3. Performance and efficiency evaluation and heat release study of a direct-injection stratified-charge rotary engine

    Science.gov (United States)

    Nguyen, H. L.; Addy, H. E.; Bond, T. H.; Lee, C. M.; Chun, K. S.

    1987-01-01

    A computer simulation which models engine performance of the Direct Injection Stratified Charge (DISC) rotary engines was used to study the effect of variations in engine design and operating parameters on engine performance and efficiency of an Outboard Marine Corporation (OMC) experimental rotary combustion engine. Engine pressure data were used in a heat release analysis to study the effects of heat transfer, leakage, and crevice flows. Predicted engine data were compared with experimental test data over a range of engine speeds and loads. An examination of methods to improve the performance of the rotary engine using advanced heat engine concepts such as faster combustion, reduced leakage, and turbocharging is also presented.

  4. Source Release Modeling for the Idaho National Engineering and Environmental Laboratory's Subsurface Disposal Area

    International Nuclear Information System (INIS)

    Becker, B.H.

    2002-01-01

    A source release model was developed to determine the release of contaminants into the shallow subsurface, as part of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) evaluation at the Idaho National Engineering and Environmental Laboratory's (INEEL) Subsurface Disposal Area (SDA). The output of the source release model is used as input to the subsurface transport and biotic uptake models. The model allowed separating the waste into areas that match the actual disposal units. This allows quantitative evaluation of the relative contribution to the total risk and allows evaluation of selective remediation of the disposal units within the SDA

  5. Performance and heat release analysis of a pilot-ignited natural gas engine

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, S.R.; Biruduganti, M.; Mo, Y.; Bell, S.R.; Midkiff, K.C. [Alabama Univ., Dept. of Mechanical Engineering, Tuscaloosa, AL (United States)

    2002-09-01

    The influence of engine operating variables on the performance, emissions and heat release in a compression ignition engine operating in normal diesel and dual-fuel modes (with natural gas fuelling) was investigated. Substantial reductions in NO{sub x} emissions were obtained with dual-fuel engine operation. There was a corresponding increase in unburned hydrocarbon emissions as the substitution of natural gas was increased. Brake specific energy consumption decreased with natural gas substitution at high loads but increased at low loads. Experimental results at fixed pilot injection timing have also established the importance of intake manifold pressure and temperature in improving dual-fuel performance and emissions at part load. (Author)

  6. In vivo drug release behavior and osseointegration of a doxorubicin-loaded tissue-engineered scaffold

    DEFF Research Database (Denmark)

    Sun, Ming; Chen, Muwan; Wang, Miao

    2016-01-01

    Bone tissue-engineered scaffolds with therapeutic effects must meet the basic requirements as to support bone healing at the defect side and to release an effect drug within the therapeutic window. Here, a rapid prototyped PCL scaffold embedded with chitosan/nanoclay/β-tricalcium phosphate...

  7. Approaches to evaluating weathering effects on release of engineered nanomaterials from solid matrices

    Science.gov (United States)

    Increased production and use of engineered nanomaterials (ENMs) over the past decade has increased the potential for the transport and release of these materials into the environment. Here we present results of two separate studies designed to simulate the effects of weathering o...

  8. Release mechanisms from shallow engineered trenches used as repositories for radioactive wastes

    International Nuclear Information System (INIS)

    Locke, J.; Wood, E.

    1987-05-01

    This report has been written for the Department of the Environment as part of their radioactive waste management research programme. The aim has been to identify release mechanisms of radioactivity from fully engineered trenches of the LAND 2 type and, to identify the data needed for their assessment. No direct experimental work has been involved. The report starts with a brief background to UK strategy and outlines a basic disposal system. It gives reviews of existing experience of low level radioactive waste disposal from LAND 1 trenches and of UK experience of toxic waste disposal to provide a practical basis for the next section which covers the implications of identified release mechanisms on the design requirements for an engineered trench. From these design requirements and their interaction with potential site conditions (both saturated and unsaturated zone sites are considered) an assessment of radionuclide release mechanism is made. (author)

  9. Release of engineered nanomaterials from polymer nanocomposites: the effect of matrix degradation.

    Science.gov (United States)

    Duncan, Timothy V

    2015-01-14

    Polymer nanocomposites-polymer-based materials that incorporate filler elements possessing at least one dimension in the nanometer range-are increasingly being developed for commercial applications ranging from building infrastructure to food packaging to biomedical devices and implants. Despite a wide range of intended applications, it is also important to understand the potential for exposure to these nanofillers, which could be released during routine use or abuse of these materials so that it can be determined whether they pose a risk to human health or the environment. This article is the second of a pair that review what is known about the release of engineered nanomaterials (ENMs) from polymer nanocomposites. Two roughly separate ENM release paradigms are considered in this series: the release of ENMs via passive diffusion, desorption, and dissolution into external liquid media and the release of ENMs assisted by matrix degradation. The present article is focused primarily on the second paradigm and includes a thorough, critical review of the associated body of peer-reviewed literature on ENM release by matrix degradation mechanisms, including photodegradation, thermal decomposition, mechanical wear, and hydrolysis. These release mechanisms may be especially relevant to nanocomposites that are likely to be subjected to weathering, including construction and infrastructural materials, sporting equipment, and materials that might potentially end up in landfills. This review pays particular attention to studies that shed light on specific release mechanisms and synergistic mechanistic relationships. The review concludes with a short section on knowledge gaps and future research needs.

  10. Surface-Engineered Nanocontainers Based on Molecular Self-Assembly and Their Release of Methenamine

    Directory of Open Access Journals (Sweden)

    Minghui Zhang

    2018-02-01

    Full Text Available The mixing of polymers and nanoparticles is opening pathways for engineering flexible composites that exhibit advantageous functional properties. To fabricate controllable assembling nanocomposites for efficiently encapsulating methenamine and releasing them on demand, we functionalized the surface of natural halloysite nanotubes (HNTs selectively with polymerizable gemini surfactant which has peculiar aggregation behavior, aiming at endowing the nanomaterials with self-assembly and stimulative responsiveness characteristics. The micromorphology, grafted components and functional groups were identified using transmission electron microscopy (TEM, thermogravimetric analysis (TGA, Fourier transform infrared (FTIR spectroscopy, and X-ray photoelectron spectroscopy (XPS. The created nanocomposites presented various characteristics of methenamine release with differences in the surface composition. It is particularly worth mentioning that the controlled release was more efficient with the increase of geminized monomer proportion, which is reasonably attributed to the fact that the amphiphilic geminized moieties with positive charge and obvious hydrophobic interactions interact with the outer and inner surface in different ways through fabricating polymeric shell as release stoppers at nanotube ends and forming polymer brush into the nanotube lumen for guest immobilization. Meanwhile, the nanocomposites present temperature and salinity responsive characteristics for the release of methenamine. The combination of HNTs with conjugated functional polymers will open pathways for engineering flexible composites which are promising for application in controlled release fields.

  11. Drug-releasing nano-engineered titanium implants: therapeutic efficacy in 3D cell culture model, controlled release and stability

    Energy Technology Data Exchange (ETDEWEB)

    Gulati, Karan [School of Chemical Engineering, The University of Adelaide, SA 5005 (Australia); Kogawa, Masakazu; Prideaux, Matthew; Findlay, David M. [Discipline of Orthopaedics and Trauma, The University of Adelaide, SA 5005 (Australia); Atkins, Gerald J., E-mail: gerald.atkins@adelaide.edu.au [Discipline of Orthopaedics and Trauma, The University of Adelaide, SA 5005 (Australia); Losic, Dusan, E-mail: dusan.losic@adelaide.edu.au [School of Chemical Engineering, The University of Adelaide, SA 5005 (Australia)

    2016-12-01

    There is an ongoing demand for new approaches for treating localized bone pathologies. Here we propose a new strategy for treatment of such conditions, via local delivery of hormones/drugs to the trauma site using drug releasing nano-engineered implants. The proposed implants were prepared in the form of small Ti wires/needles with a nano-engineered oxide layer composed of array of titania nanotubes (TNTs). TNTs implants were inserted into a 3D collagen gel matrix containing human osteoblast-like, and the results confirmed cell migration onto the implants and their attachment and spread. To investigate therapeutic efficacy, TNTs/Ti wires loaded with parathyroid hormone (PTH), an approved anabolic therapeutic for the treatment of severe bone fractures, were inserted into 3D gels containing osteoblast-like cells. Gene expression studies revealed a suppression of SOST (sclerostin) and an increase in RANKL (receptor activator of nuclear factor kappa-B ligand) mRNA expression, confirming the release of PTH from TNTs at concentrations sufficient to alter cell function. The performance of the TNTs wire implants using an example of a drug needed at relatively higher concentrations, the anti-inflammatory drug indomethacin, is also demonstrated. Finally, the mechanical stability of the prepared implants was tested by their insertion into bovine trabecular bone cores ex vivo followed by retrieval, which confirmed the robustness of the TNT structures. This study provides proof of principle for the suitability of the TNT/Ti wire implants for localized bone therapy, which can be customized to cater for specific therapeutic requirements. - Highlights: • Ti wire with titania nanotubes (TNTs) are proposed as ‘in-bone’ therapeutic implants. • 3D cell culture model is used to confirm therapeutic efficacy of drug releasing implants. Osteoblasts migrated and firmly attached to the TNTs and the micro-scale cracks. • Tailorable drug loading from few nanograms to several hundred

  12. Towards efficient bioethanol production from agricultural and forestry residues: Exploration of unique natural microorganisms in combination with advanced strain engineering.

    Science.gov (United States)

    Zhao, Xinqing; Xiong, Liang; Zhang, Mingming; Bai, Fengwu

    2016-09-01

    Production of fuel ethanol from lignocellulosic feedstocks such as agricultural and forestry residues is receiving increasing attention due to the unsustainable supply of fossil fuels. Three key challenges include high cellulase production cost, toxicity of the cellulosic hydrolysate to microbial strains, and poor ability of fermenting microorganisms to utilize certain fermentable sugars in the hydrolysate. In this article, studies on searching of natural microbial strains for production of unique cellulase for biorefinery of agricultural and forestry wastes, as well as development of strains for improved cellulase production were reviewed. In addition, progress in the construction of yeast strains with improved stress tolerance and the capability to fully utilize xylose and glucose in the cellulosic hydrolysate was also summarized. With the superior microbial strains for high titer cellulase production and efficient utilization of all fermentable sugars in the hydrolysate, economic biofuels production from agricultural residues and forestry wastes can be realized. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Influences of use activities and waste management on environmental releases of engineered nanomaterials

    International Nuclear Information System (INIS)

    Wigger, Henning; Hackmann, Stephan; Zimmermann, Till; Köser, Jan; Thöming, Jorg; Gleich, Arnim von

    2015-01-01

    Engineered nanomaterials (ENM) offer enhanced or new functionalities and properties that are used in various products. This also entails potential environmental risks in terms of hazard and exposure. However, hazard and exposure assessment for ENM still suffer from insufficient knowledge particularly for product-related releases and environmental fate and behavior. This study therefore analyzes the multiple impacts of the product use, the properties of the matrix material, and the related waste management system (WMS) on the predicted environmental concentration (PEC) by applying nine prospective life cycle release scenarios based on reasonable assumptions. The products studied here are clothing textiles treated with silver nanoparticles (AgNPs), since they constitute a controversial application. Surprisingly, the results show counter-intuitive increases by a factor of 2.6 in PEC values for the air compartment in minimal AgNP release scenarios. Also, air releases can shift from washing to wearing activity; their associated release points may shift accordingly, potentially altering release hot spots. Additionally, at end-of-life, the fraction of AgNP-residues contained on exported textiles can be increased by 350% when assuming short product lifespans and globalized WMS. It becomes evident that certain combinations of use activities, matrix material characteristics, and WMS can influence the regional PEC by several orders of magnitude. Thus, in the light of the findings and expected ENM market potential, future assessments should consider these aspects to derive precautionary design alternatives and to enable prospective global and regional risk assessments. - Highlights: • Textile use activities and two waste management systems (WMSs) are investigated. • Matrix material and use activities determine the ENM release. • Counter-intuitive shifts of releases to air can happen during usage. • WMS export can increase by 350% in case of short service life and

  14. Influences of use activities and waste management on environmental releases of engineered nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Wigger, Henning, E-mail: hwigger@uni-bremen.de [Faculty of Production Engineering, Department of Technological Design and Development, University of Bremen, Badgasteiner Str. 1, 28359 Bremen (Germany); Hackmann, Stephan [UFT Center for Environmental Research and Sustainable Technology, Department of General and Theoretical Ecology, University of Bremen, Leobener Str., 28359 Bremen (Germany); Zimmermann, Till [Faculty of Production Engineering, Department of Technological Design and Development, University of Bremen, Badgasteiner Str. 1, 28359 Bremen (Germany); ARTEC — Research Center for Sustainability Studies, Enrique-Schmidt-Str. 7, 28359 Bremen (Germany); Köser, Jan [UFT Center for Environmental Research and Sustainable Technology, Department of Sustainable Chemistry, University of Bremen, Leobener Str., 28359 Bremen (Germany); Thöming, Jorg [UFT Center for Environmental Research and Sustainable Technology, Department of Sustainable Chemical Engineering, University of Bremen, Leobener Str., 28359 Bremen (Germany); Gleich, Arnim von [Faculty of Production Engineering, Department of Technological Design and Development, University of Bremen, Badgasteiner Str. 1, 28359 Bremen (Germany); ARTEC — Research Center for Sustainability Studies, Enrique-Schmidt-Str. 7, 28359 Bremen (Germany)

    2015-12-01

    Engineered nanomaterials (ENM) offer enhanced or new functionalities and properties that are used in various products. This also entails potential environmental risks in terms of hazard and exposure. However, hazard and exposure assessment for ENM still suffer from insufficient knowledge particularly for product-related releases and environmental fate and behavior. This study therefore analyzes the multiple impacts of the product use, the properties of the matrix material, and the related waste management system (WMS) on the predicted environmental concentration (PEC) by applying nine prospective life cycle release scenarios based on reasonable assumptions. The products studied here are clothing textiles treated with silver nanoparticles (AgNPs), since they constitute a controversial application. Surprisingly, the results show counter-intuitive increases by a factor of 2.6 in PEC values for the air compartment in minimal AgNP release scenarios. Also, air releases can shift from washing to wearing activity; their associated release points may shift accordingly, potentially altering release hot spots. Additionally, at end-of-life, the fraction of AgNP-residues contained on exported textiles can be increased by 350% when assuming short product lifespans and globalized WMS. It becomes evident that certain combinations of use activities, matrix material characteristics, and WMS can influence the regional PEC by several orders of magnitude. Thus, in the light of the findings and expected ENM market potential, future assessments should consider these aspects to derive precautionary design alternatives and to enable prospective global and regional risk assessments. - Highlights: • Textile use activities and two waste management systems (WMSs) are investigated. • Matrix material and use activities determine the ENM release. • Counter-intuitive shifts of releases to air can happen during usage. • WMS export can increase by 350% in case of short service life and

  15. Evaluating protein incorporation and release in electrospun composite scaffolds for bone tissue engineering applications.

    Science.gov (United States)

    Briggs, Tonye; Matos, Jeffrey; Collins, George; Arinzeh, Treena Livingston

    2015-10-01

    Electrospun polymer/ceramic composites have gained interest for use as scaffolds for bone tissue engineering applications. In this study, we investigated methods to incorporate Platelet Derived Growth Factor-BB (PDGF-BB) in electrospun polycaprolactone (PCL) or PCL prepared with polyethylene oxide (PEO), where both contained varying levels (up to 30 wt %) of ceramic composed of biphasic calcium phosphates, hydroxyapatite (HA)/β-tricalcium phosphate (TCP). Using a model protein, lysozyme, we compared two methods of protein incorporation, adsorption and emulsion electrospinning. Adsorption of lysozyme on scaffolds with ceramic resulted in minimal release of lysozyme over time. Using emulsion electrospinning, lysozyme released from scaffolds containing a high concentration of ceramic where the majority of the release occurred at later time points. We investigated the effect of reducing the electrostatic interaction between the protein and the ceramic on protein release with the addition of the cationic surfactant, cetyl trimethylammonium bromide (CTAB). In vitro release studies demonstrated that electrospun scaffolds prepared with CTAB released more lysozyme or PDGF-BB compared with scaffolds without the cationic surfactant. Human mesenchymal stem cells (MSCs) on composite scaffolds containing PDGF-BB incorporated through emulsion electrospinning expressed higher levels of osteogenic markers compared to scaffolds without PDGF-BB, indicating that the bioactivity of the growth factor was maintained. This study revealed methods for incorporating growth factors in polymer/ceramic scaffolds to promote osteoinduction and thereby facilitate bone regeneration. © 2015 Wiley Periodicals, Inc.

  16. Fabrication and characterization of a rapid prototyped tissue engineering scaffold with embedded multicomponent matrix for controlled drug release

    DEFF Research Database (Denmark)

    Chen, Muwan; Le, Dang Q S; Hein, San

    2012-01-01

    Bone tissue engineering implants with sustained local drug delivery provide an opportunity for better postoperative care for bone tumor patients because these implants offer sustained drug release at the tumor site and reduce systemic side effects. A rapid prototyped macroporous polycaprolactone......, this scaffold can fulfill the requirements for both bone tissue engineering and local sustained release of an anticancer drug in vitro. These results suggest that the scaffold can be used clinically in reconstructive surgery after bone tumor resection. Moreover, by changing the composition and amount...... of individual components, the scaffold can find application in other tissue engineering areas that need local sustained release of drug....

  17. Effect of Engineered Nanoparticles on Exopolymeric Substances Release from Marine Phytoplankton

    Science.gov (United States)

    Chiu, Meng-Hsuen; Khan, Zafir A.; Garcia, Santiago G.; Le, Andre D.; Kagiri, Agnes; Ramos, Javier; Tsai, Shih-Ming; Drobenaire, Hunter W.; Santschi, Peter H.; Quigg, Antonietta; Chin, Wei-Chun

    2017-12-01

    Engineered nanoparticles (ENPs), products from modern nanotechnologies, can potentially impact the marine environment to pose serious threats to marine ecosystems. However, the cellular responses of marine phytoplankton to ENPs are still not well established. Here, we investigate four different diatom species ( Odontella mobiliensis, Skeletonema grethae, Phaeodactylum tricornutum, Thalassiosira pseudonana) and one green algae ( Dunaliella tertiolecta) for their extracellular polymeric substances (EPS) release under model ENP treatments: 25 nm titanium dioxide (TiO2), 10-20 nm silicon dioxide (SiO2), and 15-30 nm cerium dioxide (CeO2). We found SiO2 ENPs can significantly stimulate EPS release from these algae (200-800%), while TiO2 ENP exposure induced the lowest release. Furthermore, the increase of intracellular Ca2+ concentration can be triggered by ENPs, suggesting that the EPS release process is mediated through Ca2+ signal pathways. With better understanding of the cellular mechanism mediated ENP-induced EPS release, potential preventative and safety measures can be developed to mitigate negative impact on the marine ecosystem.

  18. An Experimental Investigation on the Combustion and Heat Release Characteristics of an Opposed-Piston Folded-Cranktrain Diesel Engine

    Directory of Open Access Journals (Sweden)

    Fukang Ma

    2015-06-01

    Full Text Available In opposed-piston folded-cranktrain diesel engines, the relative movement rules of opposed-pistons, combustion chamber components and injector position are different from those of conventional diesel engines. The combustion and heat release characteristics of an opposed-piston folded-cranktrain diesel engine under different operating conditions were investigated. Four phases: ignition delay, premixed combustion, diffusion combustion and after combustion are used to describe the heat release process of the engine. Load changing has a small effect on premixed combustion duration while it influences diffusion combustion duration significantly. The heat release process has more significant isochoric and isobaric combustion which differs from the conventional diesel engine situation, except at high exhaust pressure and temperature, due to its two-stroke and uniflow scavenging characteristics. Meanwhile, a relatively high-quality exhaust heat energy is produced in opposed-piston folded-cranktrain diesel engines.

  19. Development of criteria for release of Idaho National Engineering Laboratory sites following decontamination and decommissioning

    International Nuclear Information System (INIS)

    Kirol, L.

    1986-08-01

    Criteria have been developed for release of Idaho National Engineering Laboratory (INEL) facilities and land areas following decontamination and decommissioning (D and D). Although these facilities and land areas are not currently being returned to the public domain, and no plans exist for doing so, criteria suitable for unrestricted release to the public were desired. Midway through this study, the implementation of Department of Energy (DOE) Order 5820.2, Radioactive Waste Management, required development of site specific release criteria for use on D and D projects. These criteria will help prevent remedial actions from being required if INEL reuse considerations change in the future. Development of criteria for release of INEL facilities following D and D comprised four study areas: pathways analysis, dose and concentration guidelines, sampling and instrumentation, and implementation procedures. Because of the complex and sensitive nature of the first three categories, a thorough review by experts in those respective fields was desired. Input and support in preparing or reviewing each part of the criteria development task was solicited from several DOE field offices. Experts were identified and contracted to assist in preparing portions of the release criteria, or to serve on a peer-review committee. Thus, the entire release criteria development task was thoroughly reviewed by recognized experts from contractors at several DOE field offices, to validate technical content of the document. Each of the above four study areas was developed originally as an individual task, and a report was generated from each. These reports are combined here to form this document. This release criteria document includes INEL-specific pathways analysis, instrumentation requirements, sampling procedures, the basis for selection of dose and concentration guidelines, and cost-risk-benefit procedures

  20. Open field release of genetically engineered sterile male Aedes aegypti in Malaysia.

    Directory of Open Access Journals (Sweden)

    Renaud Lacroix

    Full Text Available BACKGROUND: Dengue is the most important mosquito-borne viral disease. In the absence of specific drugs or vaccines, control focuses on suppressing the principal mosquito vector, Aedes aegypti, yet current methods have not proven adequate to control the disease. New methods are therefore urgently needed, for example genetics-based sterile-male-release methods. However, this requires that lab-reared, modified mosquitoes be able to survive and disperse adequately in the field. METHODOLOGY/PRINCIPAL FINDINGS: Adult male mosquitoes were released into an uninhabited forested area of Pahang, Malaysia. Their survival and dispersal was assessed by use of a network of traps. Two strains were used, an engineered 'genetically sterile' (OX513A and a wild-type laboratory strain, to give both absolute and relative data about the performance of the modified mosquitoes. The two strains had similar maximum dispersal distances (220 m, but mean distance travelled of the OX513A strain was lower (52 vs. 100 m. Life expectancy was similar (2.0 vs. 2.2 days. Recapture rates were high for both strains, possibly because of the uninhabited nature of the site. CONCLUSIONS/SIGNIFICANCE: After extensive contained studies and regulatory scrutiny, a field release of engineered mosquitoes was safely and successfully conducted in Malaysia. The engineered strain showed similar field longevity to an unmodified counterpart, though in this setting dispersal was reduced relative to the unmodified strain. These data are encouraging for the future testing and implementation of genetic control strategies and will help guide future field use of this and other engineered strains.

  1. Composite microsphere-functionalized scaffold for the controlled release of small molecules in tissue engineering

    Directory of Open Access Journals (Sweden)

    Laura Pandolfi

    2016-01-01

    Full Text Available Current tissue engineering strategies focus on restoring damaged tissue architectures using biologically active scaffolds. The ideal scaffold would mimic the extracellular matrix of any tissue of interest, promoting cell proliferation and de novo extracellular matrix deposition. A plethora of techniques have been evaluated to engineer scaffolds for the controlled and targeted release of bioactive molecules to provide a functional structure for tissue growth and remodeling, as well as enhance recruitment and proliferation of autologous cells within the implant. Recently, novel approaches using small molecules, instead of growth factors, have been exploited to regulate tissue regeneration. The use of small synthetic molecules could be very advantageous because of their stability, tunability, and low cost. Herein, we propose a chitosan–gelatin scaffold functionalized with composite microspheres consisting of mesoporous silicon microparticles and poly(dl-lactic-co-glycolic acid for the controlled release of sphingosine-1-phospate, a small molecule of interest. We characterized the platform with scanning electron microscopy, Fourier transform infrared spectroscopy, and confocal microscopy. Finally, the biocompatibility of this multiscale system was analyzed by culturing human mesenchymal stem cells onto the scaffold. The presented strategy establishes the basis of a versatile scaffold for the controlled release of small molecules and for culturing mesenchymal stem cells for regenerative medicine applications.

  2. Recent advances in the metabolic engineering of microorganisms for the production of 3-hydroxypropionic acid as C3 platform chemical.

    Science.gov (United States)

    Valdehuesa, Kris Niño G; Liu, Huaiwei; Nisola, Grace M; Chung, Wook-Jin; Lee, Seung Hwan; Park, Si Jae

    2013-04-01

    Development of sustainable technologies for the production of 3-hydroxypropionic acid (3HP) as a platform chemical has recently been gaining much attention owing to its versatility in applications for the synthesis of other specialty chemicals. Several proposed biological synthesis routes and strategies for producing 3HP from glucose and glycerol are reviewed presently. Ten proposed routes for 3HP production from glucose are described and one of which was recently constructed successfully in Escherichia coli with malonyl-Coenzyme A as a precursor. This resulted in a yield still far from the required level for industrial application. On the other hand, strategies employing engineered E. coli and Klebsiella pneumoniae capable of producing 3HP from glycerol are also evaluated. The titers produced by these recombinant strains reached around 3 %. At its current state, it is evident that a bulk of engineering works is yet to be done to acquire a biosynthesis route for 3HP that is acceptable for industrial-scale production.

  3. Lignite microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Bulankina, M.A.; Lysak, L.V.; Zvyagintsev, D.G. [Moscow MV Lomonosov State University, Moscow (Russian Federation). Faculty of Soil Science

    2007-03-15

    The first demonstration that samples of lignite at a depth of 10 m are considerably enriched in bacteria is reported. According to direct microscopy, the abundance of bacteria was about 10{sup 7} cells/g. About 70% of cells had intact cell membranes and small size, which points to their anabiotic state. The fungal mycelium length was no more than 1 m. Lignite inoculation onto solid glucose-yeast-peptone medium allowed us to isolate bacteria of the genera Bacillus, Rhodococcus, Arthrobacter, Micrococcus, Spirillum, and Cytophaga. Representatives of the genera Penicillium and Trichoderma were identified on Czapek medium. Moistening of lignite powder increased the microbial respiration rate and microbial and fungal abundance but did not increase their generic diversity. This finding suggests that the studied microorganisms are autochthonous to lignite.

  4. Combustion Heat Release Rate Comparison of Algae Hydroprocessed Renewable Diesel to F-76 in a Two-Stroke Diesel Engine

    Science.gov (United States)

    2013-06-01

    was recorded. Figure 14 shows the gauge on the rocker arm during calibration . Figure 14. Mechanical Injector Rocker Arm Strain Gauge. D. DATA...RELEASE RATE COMPARISON OF ALGAE HYDROPROCESSED RENEWABLE DIESEL TO F-76 IN A TWO-STROKE DIESEL ENGINE by John H. Petersen June 2013 Thesis...RELEASE RATE COMPARISON OF ALGAE HYDROPROCESSED RENEWABLE DIESEL TO F-76 IN A TWO-STROKE DIESEL ENGINE 5. FUNDING NUMBERS 6. AUTHOR(S) John H

  5. Sensitivity of the engineered barrier system (EBS) release rate to alternative conceptual models of advective release from waste packages under dripping fractures

    International Nuclear Information System (INIS)

    Lee, J.H.; Atkins, J.E.; McNeish, J.A.; Vallikat, V.

    1996-01-01

    Simulations were conducted to analyze the sensitivity of the engineered barrier system (EBS) release rate to alternative conceptual models of the advective release from waste packages under dripping fractures. The first conceptual model assumed that dripping water directly contacts the waste form inside the 'failed' waste package, and radionuclides are released from the EBS by advection. The second conceptual model assumed that dripping water is diverted around the 'failed' waste package (because of the presence of corrosion products plugging the perforations) and dripping water is prevented from directly contacting the waste form. In the second model, radionuclides were assumed to transport through the perforations by diffusion, and, once outside the waste package, to be released from the EBS by advection. The second model was to incorporate more realism into the EBS release calculations. For the case with the second EBS release model, most radionuclides had significantly lower peak EBS release rates (from at least one to several orders of magnitude) than with the first EBS release model. The impacts of the alternative EBS release models were greater for the radionuclides with a low solubility (or solubility-limited radionuclides) than for the radionuclides with a high solubility (or waste form dissolution-limited radionuclides). The analyses indicated that the EBS release model representing advection through a 'failed' waste package (the first EBS release model) may be too conservative in predicting the EBS performance. One major implication from this sensitivity study was that a 'failed' waste package container with multiple perforations may still be able to perform effectively as an important barrier to radionuclide release. (author)

  6. Airborne engineered nanomaterials in the workplace—a review of release and worker exposure during nanomaterial production and handling processes

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Yaobo [Institute for Work and Health (IST), Universities of Lausanne and Geneva, Route de la Corniche 2, 1066, Epalinges (Switzerland); Kuhlbusch, Thomas A.J. [Institute of Energy and Environmental Technology (IUTA), Air Quality & Sustainable Nanotechnology Unit, Bliersheimer Straße 58-60, 47229 Duisburg (Germany); Centre for Nanointegration (CENIDE), University Duisburg-Essen, Duisburg (Germany); Van Tongeren, Martie; Jiménez, Araceli Sánchez [Centre for Human Exposure Science, Institute of Occupational Medicine (IOM), Research Avenue North, Edinburgh EH14 4AP (United Kingdom); Tuinman, Ilse [TNO, Lange Kleiweg 137, Rijswijk (Netherlands); Chen, Rui [CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology of China, Beijing 100190 (China); Alvarez, Iñigo Larraza [ACCIONA Infrastructure, Materials Area, Innovation Division, C/Valportillo II 8, 28108, Alcobendas (Spain); Mikolajczyk, Urszula [Nofer Institute of Occupational Medicine, Lodz (Poland); Nickel, Carmen; Meyer, Jessica; Kaminski, Heinz [Institute of Energy and Environmental Technology (IUTA), Air Quality & Sustainable Nanotechnology Unit, Bliersheimer Straße 58-60, 47229 Duisburg (Germany); Wohlleben, Wendel [Dept. Material Physics, BASF SE, Advanced Materials Research, Ludwigshafen (Germany); Stahlmecke, Burkhard [Institute of Energy and Environmental Technology (IUTA), Air Quality & Sustainable Nanotechnology Unit, Bliersheimer Straße 58-60, 47229 Duisburg (Germany); Clavaguera, Simon [NanoSafety Platform, Commissariat à l’Energie Atomique et aux Energies Alternatives (CEA), Univ. Grenoble Alpes, Grenoble, 38054 (France); and others

    2017-01-15

    Highlights: • Release characteristics can be grouped by the type of occupational activities. • Release levels may be linked to process energy. • A better data reporting practice will facilitate exposure assessment. • The results help prioritize industrial processes for human risk assessment. - Abstract: For exposure and risk assessment in occupational settings involving engineered nanomaterials (ENMs), it is important to understand the mechanisms of release and how they are influenced by the ENM, the matrix material, and process characteristics. This review summarizes studies providing ENM release information in occupational settings, during different industrial activities and using various nanomaterials. It also assesses the contextual information — such as the amounts of materials handled, protective measures, and measurement strategies — to understand which release scenarios can result in exposure. High-energy processes such as synthesis, spraying, and machining were associated with the release of large numbers of predominantly small-sized particles. Low-energy processes, including laboratory handling, cleaning, and industrial bagging activities, usually resulted in slight or moderate releases of relatively large agglomerates. The present analysis suggests that process-based release potential can be ranked, thus helping to prioritize release assessments, which is useful for tiered exposure assessment approaches and for guiding the implementation of workplace safety strategies. The contextual information provided in the literature was often insufficient to directly link release to exposure. The studies that did allow an analysis suggested that significant worker exposure might mainly occur when engineering safeguards and personal protection strategies were not carried out as recommended.

  7. Airborne engineered nanomaterials in the workplace—a review of release and worker exposure during nanomaterial production and handling processes

    International Nuclear Information System (INIS)

    Ding, Yaobo; Kuhlbusch, Thomas A.J.; Van Tongeren, Martie; Jiménez, Araceli Sánchez; Tuinman, Ilse; Chen, Rui; Alvarez, Iñigo Larraza; Mikolajczyk, Urszula; Nickel, Carmen; Meyer, Jessica; Kaminski, Heinz; Wohlleben, Wendel; Stahlmecke, Burkhard; Clavaguera, Simon

    2017-01-01

    Highlights: • Release characteristics can be grouped by the type of occupational activities. • Release levels may be linked to process energy. • A better data reporting practice will facilitate exposure assessment. • The results help prioritize industrial processes for human risk assessment. - Abstract: For exposure and risk assessment in occupational settings involving engineered nanomaterials (ENMs), it is important to understand the mechanisms of release and how they are influenced by the ENM, the matrix material, and process characteristics. This review summarizes studies providing ENM release information in occupational settings, during different industrial activities and using various nanomaterials. It also assesses the contextual information — such as the amounts of materials handled, protective measures, and measurement strategies — to understand which release scenarios can result in exposure. High-energy processes such as synthesis, spraying, and machining were associated with the release of large numbers of predominantly small-sized particles. Low-energy processes, including laboratory handling, cleaning, and industrial bagging activities, usually resulted in slight or moderate releases of relatively large agglomerates. The present analysis suggests that process-based release potential can be ranked, thus helping to prioritize release assessments, which is useful for tiered exposure assessment approaches and for guiding the implementation of workplace safety strategies. The contextual information provided in the literature was often insufficient to directly link release to exposure. The studies that did allow an analysis suggested that significant worker exposure might mainly occur when engineering safeguards and personal protection strategies were not carried out as recommended.

  8. [Construction and evaluation of the tissue engineered nerve of bFGF-PLGA sustained release microspheres].

    Science.gov (United States)

    Wang, Guanglin; Lin, Wei; Gao, Weiqiang; Xiao, Yuhua; Dong, Changchao

    2008-12-01

    To study the outcomes of nerve defect repair with the tissue engineered nerve, which is composed of the complex of SCs, 30% ECM gel, bFGF-PLGA sustained release microspheres, PLGA microfilaments and permeable poly (D, L-lactic acid) (PDLLA) catheters. SCs were cultured and purified from the sciatic nerves of 1-day-old neonatal SD rats. The 1st passage cells were compounded with bFGF-PLGA sustained release microspheres and ECM gel, and then were injected into permeable PDLLA catheters with PLGA microfilaments inside. In this way, the tissue engineered nerve was constructed. Sixty SD rats were included. The model of 15-mm sciatic nerve defects was made, and then the rats were randomly divided into 5 groups, with 12 rats in each. In group A, autograft was adopted. In group B, the blank PDLLA catheters with PBS inside were used. In group C, PDLLA catheters, with PLGA microfilaments and 30% ECM gel inside, were used. In group D, PDLLA catheters, with PLGA microfilaments, SCs and 30% ECM gel inside, were used. In group E, the tissue engineered nerve was applied. After the operation, observation was made for general conditions of the rats. The sciatic function index (SFI) analysis was performed at 12, 16, 20 and 24 weeks after the operation, respectively. Electrophysiological detection and histological observation were performed at 12 and 24 weeks after the operation, respectively. All rats survived to the end of the experiment. At 12 and 16 weeks after the operation, group E was significantly different from group B in SFI (P fibers in group E were significantly differents from those in groups A, B and C (P fibers in group E were smaller than those in group A (P fibers in group E was significantly different from those in groups A, B, C (P fibers in group E were bigger than those in groups B and C (P < 0.05). The tissue engineered nerve with the complex of SCs, ECM gel, bFGF-PLGA sustained release microspheres, PLGA microfilaments and permeable PDLLA catheters promote

  9. Sustained release of sphingosine 1-phosphate for therapeutic arteriogenesis and bone tissue engineering.

    Science.gov (United States)

    Sefcik, Lauren S; Petrie Aronin, Caren E; Wieghaus, Kristen A; Botchwey, Edward A

    2008-07-01

    Sphingosine 1-phosphate (S1P) is a bioactive phospholipid that impacts migration, proliferation, and survival in diverse cell types, including endothelial cells, smooth muscle cells, and osteoblast-like cells. In this study, we investigated the effects of sustained release of S1P on microvascular remodeling and associated bone defect healing in vivo. The murine dorsal skinfold window chamber model was used to evaluate the structural remodeling response of the microvasculature. Our results demonstrated that 1:400 (w/w) loading and subsequent sustained release of S1P from poly(lactic-co-glycolic acid) (PLAGA) significantly enhanced lumenal diameter expansion of arterioles and venules after 3 and 7 days. Incorporation of 5-bromo-2-deoxyuridine (BrdU) at day 7 revealed significant increases in mural cell proliferation in response to S1P delivery. Additionally, three-dimensional (3D) scaffolds loaded with S1P (1:400) were implanted into critical-size rat calvarial defects, and healing of bony defects was assessed by radiograph X-ray, microcomputed tomography (muCT), and histology. Sustained release of S1P significantly increased the formation of new bone after 2 and 6 weeks of healing and histological results suggest increased numbers of blood vessels in the defect site. Taken together, these experiments support the use of S1P delivery for promoting microvessel diameter expansion and improving the healing outcomes of tissue-engineered therapies.

  10. Heat release and engine performance effects of soybean oil ethyl ester blending into diesel fuel

    International Nuclear Information System (INIS)

    Bueno, Andre Valente; Velasquez, Jose Antonio; Milanez, Luiz Fernando

    2011-01-01

    The engine performance impact of soybean oil ethyl ester blending into diesel fuel was analyzed employing heat release analysis, in-cylinder exergy balances and dynamometric tests. Blends with concentrations of up to 30% of soybean oil ethyl ester in volume were used in steady-state experiments conducted in a high speed turbocharged direct injection engine. Modifications in fuel heat value, fuel-air equivalence ratio and combustion temperature were found to govern the impact resulting from the addition of biodiesel on engine performance. For the analyzed fuels, the 20% biodiesel blend presented the best results of brake thermal efficiency, while the 10% biodiesel blend presented the best results of brake power and sfc (specific fuel consumption). In relation to mineral diesel and in full load conditions, an average increase of 4.16% was observed in brake thermal efficiency with B20 blend. In the same conditions, an average gain of 1.15% in brake power and a reduction of 1.73% in sfc was observed with B10 blend.

  11. Applications of human factors engineering to LNG release prevention and control

    Energy Technology Data Exchange (ETDEWEB)

    Shikiar, R.; Rankin, W.L.; Rideout, T.B.

    1982-06-01

    The results of an investigation of human factors engineering and human reliability applications to LNG release prevention and control are reported. The report includes a discussion of possible human error contributions to previous LNG accidents and incidents, and a discussion of generic HF considerations for peakshaving plants. More specific recommendations for improving HF practices at peakshaving plants are offered based on visits to six facilities. The HF aspects of the recently promulgated DOT regulations are reviewed, and recommendations are made concerning how these regulations can be implemented utilizing standard HF practices. Finally, the integration of HF considerations into overall system safety is illustrated by a presentation of human error probabilities applicable to LNG operations and by an expanded fault tree analysis which explicitly recognizes man-machine interfaces.

  12. Sensitivity of performance assessment of the engineered barriers to nuances of release rate criteria

    International Nuclear Information System (INIS)

    Oliver, D.L.R.

    1987-01-01

    The United States Nuclear Regulatory Commission (NRC) has established criteria for the long-term performance of proposed high-level waste repositories. As with any regulation, the criteria may be interpreted in several ways. Due to the high capital costs and the emotional political climate associated with any high-level radioactive waste repository, it is important that there be an early consensus regarding interpretations of the criteria, and what assumptions may be used to demonstrate compliance with them. This work uses analytic solutions of mass transport theory to demonstrate how sensitive performance analyses are to various nuances of the NRC release rate criterion for the engineered barriers. The analysis is directed at the proposed repository in basalt at the Hanford site in Washington State

  13. Neural tissue engineering scaffold with sustained RAPA release relieves neuropathic pain in rats.

    Science.gov (United States)

    Ding, Tan; Zhu, Chao; Kou, Zhen-Zhen; Yin, Jun-Bin; Zhang, Ting; Lu, Ya-Cheng; Wang, Li-Ying; Luo, Zhuo-Jing; Li, Yun-Qing

    2014-09-01

    To investigate the effect of locally slow-released rapamycin (RAPA) from bionic peripheral nerve stent to reduce the incidence of neuropathic pain or mitigate the degree of pain after nerve injury. We constructed a neural tissue engineering scaffold with sustained release of RAPA to repair 20mm defects in rat sciatic nerves. Four presurgical and postsurgical time windows were selected to monitor the changes in the expression of pain-related dorsal root ganglion (DRG) voltage-gated sodium channels 1.3 (Nav1.3), 1.7 (Nav1.7), and 1.8 (Nav1.8) through immunohistochemistry (IHC) and Western Blot, along with the observation of postsurgical pathological pain in rats by pain-related behavior approaches. Relatively small upregulation of DRG sodium channels was observed in the experimental group (RAPA+poly(lactic-co-glycolic acid) (PLGA)+stent) after surgery, along with low degrees of neuropathic pain and anxiety, which were similar to those in the Autologous nerve graft group. Autoimmune inflammatory response plays a leading role in the occurrence of post-traumatic neuropathic pain, and that RAPA significantly inhibits the abnormal upregulation of sodium channels to reduce pain by alleviating inflammatory response. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Simulating Exposure Concentrations of Engineered Nanomaterials in Surface Water Systems: Release of WASP8

    Science.gov (United States)

    Knightes, C. D.; Bouchard, D.; Zepp, R. G.; Henderson, W. M.; Han, Y.; Hsieh, H. S.; Avant, B. K.; Acrey, B.; Spear, J.

    2017-12-01

    The unique properties of engineered nanomaterials led to their increased production and potential release into the environment. Currently available environmental fate models developed for traditional contaminants are limited in their ability to simulate nanomaterials' environmental behavior. This is due to an incomplete understanding and representation of the processes governing nanomaterial distribution in the environment and by scarce empirical data quantifying the interaction of nanomaterials with environmental surfaces. The well-known Water Quality Analysis Simulation Program (WASP) was updated to incorporate nanomaterial-specific processes, specifically hetero-aggregation with particulate matter. In parallel with this effort, laboratory studies were used to quantify parameter values parameters necessary for governing processes in surface waters. This presentation will discuss the recent developments in the new architecture for WASP8 and the newly constructed Advanced Toxicant Module. The module includes advanced algorithms for increased numbers of state variables: chemicals, solids, dissolved organic matter, pathogens, temperature, and salinity. This presentation will focus specifically on the incorporation of nanomaterials, with the applications of the fate and transport of hypothetical releases of Multi-Walled Carbon Nanotubes (MWCNT) and Graphene Oxide (GO) into the headwaters of a southeastern US coastal plains river. While this presentation focuses on nanomaterials, the advanced toxicant module can also simulate metals and organic contaminants.

  15. Novel cobalt releasing sol-gel derived bioactive glass for bone tissue engineering

    International Nuclear Information System (INIS)

    Oliveira, Ana Celeste Ximenes; Barrioni, Breno Rocha; Leite, Maria de Fatima; Pereira, Marivalda Magalhaes

    2016-01-01

    Full text: Bone defects are caused by traumas, congenital disorders or infections, and bone grafts are the usual treatment. However, limitations of this therapy have lead to the advance of tissue engineering approaches. Bioactive glasses (BG) are an attractive bioactive ceramic for bone repair [1], due to its osteogenic properties and capability of releasing different ions, inducing specific biological responses. Tissue repair depends also on blood vessels formation. Among angiogenic agents, cobalt ion has been regarded as strategic component to incorporate into ion releasing materials. In this study, 5% (molar) cobalt releasing BG was synthesized by sol-gel method. To characterize the material, powder samples were evaluated by FTIR and DRX. To access the cytotoxic effects, MTT and LIVE/DEAD tests were performed on osteoblasts exposed to the ionic product of the material (100 μg/mL) for 72h. FTIR analysis reveals typical absorption bands of present groups in BG. X-ray diffractogram of DRX confirmed the amorphous character of BG, without the occurrence of recrystallization of cobalt precursor, suggesting that cobalt incorporation was well succeeded. MTT test showed that cells exposed to ionic product presented high levels of metabolic activity. LIVE/DEAD assay evidenced that cell membrane integrity and intracellular esterases activity were preserved. Both cytotoxic tests proved that cobalt-BG material generated a cell friendly environment. This work shows that BG with cobalt agent presented proper structural features and a non-cytotoxic behaviour. Reference: [1] Hench LL, J Mater Sci Mater Med 17(11), 967-78 (2006). (author)

  16. Metabolic engineering of a diazotrophic bacterium improves ammonium release and biofertilization of plants and microalgae.

    Science.gov (United States)

    Ambrosio, Rafael; Ortiz-Marquez, Juan Cesar Federico; Curatti, Leonardo

    2017-03-01

    The biological nitrogen fixation carried out by some Bacteria and Archaea is one of the most attractive alternatives to synthetic nitrogen fertilizers. However, with the exception of the symbiotic rhizobia-legumes system, progress towards a more extensive realization of this goal has been slow. In this study we manipulated the endogenous regulation of both nitrogen fixation and assimilation in the aerobic bacterium Azotobacter vinelandii. Substituting an exogenously inducible promoter for the native promoter of glutamine synthetase produced conditional lethal mutant strains unable to grow diazotrophically in the absence of the inducer. This mutant phenotype could be reverted in a double mutant strain bearing a deletion in the nifL gene that resulted in constitutive expression of nif genes and increased production of ammonium. Under GS non-inducing conditions both the single and the double mutant strains consistently released very high levels of ammonium (>20mM) into the growth medium. The double mutant strain grew and excreted high levels of ammonium under a wider range of concentrations of the inducer than the single mutant strain. Induced mutant cells could be loaded with glutamine synthetase at different levels, which resulted in different patterns of extracellular ammonium accumulation afterwards. Inoculation of the engineered bacteria into a microalgal culture in the absence of sources of C and N other than N 2 and CO 2 from the air, resulted in a strong proliferation of microalgae that was suppressed upon addition of the inducer. Both single and double mutant strains also promoted growth of cucumber plants in the absence of added N-fertilizer, while this property was only marginal in the parental strain. This study provides a simple synthetic genetic circuit that might inspire engineering of optimized inoculants that efficiently channel N 2 from the air into crops. Copyright © 2017 International Metabolic Engineering Society. Published by Elsevier Inc. All

  17. Fabrication and characterization of a rapid prototyped tissue engineering scaffold with embedded multicomponent matrix for controlled drug release

    Science.gov (United States)

    Chen, Muwan; Le, Dang QS; Hein, San; Li, Pengcheng; Nygaard, Jens V; Kassem, Moustapha; Kjems, Jørgen; Besenbacher, Flemming; Bünger, Cody

    2012-01-01

    Bone tissue engineering implants with sustained local drug delivery provide an opportunity for better postoperative care for bone tumor patients because these implants offer sustained drug release at the tumor site and reduce systemic side effects. A rapid prototyped macroporous polycaprolactone scaffold was embedded with a porous matrix composed of chitosan, nanoclay, and β-tricalcium phosphate by freeze-drying. This composite scaffold was evaluated on its ability to deliver an anthracycline antibiotic and to promote formation of mineralized matrix in vitro. Scanning electronic microscopy, confocal imaging, and DNA quantification confirmed that immortalized human bone marrow-derived mesenchymal stem cells (hMSC-TERT) cultured in the scaffold showed high cell viability and growth, and good cell infiltration to the pores of the scaffold. Alkaline phosphatase activity and osteocalcin staining showed that the scaffold was osteoinductive. The drug-release kinetics was investigated by loading doxorubicin into the scaffold. The scaffolds comprising nanoclay released up to 45% of the drug for up to 2 months, while the scaffold without nanoclay released 95% of the drug within 4 days. Therefore, this scaffold can fulfill the requirements for both bone tissue engineering and local sustained release of an anticancer drug in vitro. These results suggest that the scaffold can be used clinically in reconstructive surgery after bone tumor resection. Moreover, by changing the composition and amount of individual components, the scaffold can find application in other tissue engineering areas that need local sustained release of drug. PMID:22904634

  18. Engineered collagen hydrogels for the sustained release of biomolecules and imaging agents: promoting the growth of human gingival cells.

    Science.gov (United States)

    Choi, Jonghoon; Park, Hoyoung; Kim, Taeho; Jeong, Yoon; Oh, Myoung Hwan; Hyeon, Taeghwan; Gilad, Assaf A; Lee, Kwan Hyi

    2014-01-01

    We present here the in vitro release profiles of either fluorescently labeled biomolecules or computed tomography contrast nanoagents from engineered collagen hydrogels under physiological conditions. The collagen constructs were designed as potential biocompatible inserts into wounded human gingiva. The collagen hydrogels were fabricated under a variety of conditions in order to optimize the release profile of biomolecules and nanoparticles for the desired duration and amount. The collagen constructs containing biomolecules/nanoconstructs were incubated under physiological conditions (ie, 37°C and 5% CO2) for 24 hours, and the release profile was tuned from 20% to 70% of initially loaded materials by varying the gelation conditions of the collagen constructs. The amounts of released biomolecules and nanoparticles were quantified respectively by measuring the intensity of fluorescence and X-ray scattering. The collagen hydrogel we fabricated may serve as an efficient platform for the controlled release of biomolecules and imaging agents in human gingiva to facilitate the regeneration of oral tissues.

  19. Intermediate temperature heat release in an HCCI engine fueled by ethanol/n-heptane mixtures: An experimental and modeling study

    KAUST Repository

    Vuilleumier, David

    2014-03-01

    This study examines intermediate temperature heat release (ITHR) in homogeneous charge compression ignition (HCCI) engines using blends of ethanol and n-heptane. Experiments were performed over the range of 0-50% n-heptane liquid volume fractions, at equivalence ratios 0.4 and 0.5, and intake pressures from 1.4bar to 2.2bar. ITHR was induced in the mixtures containing predominantly ethanol through the addition of small amounts of n-heptane. After a critical threshold, additional n-heptane content yielded low temperature heat release (LTHR). A method for quantifying the amount of heat released during ITHR was developed by examining the second derivative of heat release, and this method was then used to identify trends in the engine data. The combustion process inside the engine was modeled using a single-zone HCCI model, and good qualitative agreement of pre-ignition pressure rise and heat release rate was found between experimental and modeling results using a detailed n-heptane/ethanol chemical kinetic model. The simulation results were used to identify the dominant reaction pathways contributing to ITHR, as well as to verify the chemical basis behind the quantification of the amount of ITHR in the experimental analysis. The dominant reaction pathways contributing to ITHR were found to be H-atom abstraction from n-heptane by OH and the addition of fuel radicals to O2. © 2013 The Combustion Institute.

  20. Intermediate temperature heat release in an HCCI engine fueled by ethanol/n-heptane mixtures: An experimental and modeling study

    KAUST Repository

    Vuilleumier, David; Kozarac, Darko; Mehl, Marco; Saxena, Samveg; Pitz, William J.; Dibble, Robert W.; Chen, Jyhyuan; Sarathy, Mani

    2014-01-01

    This study examines intermediate temperature heat release (ITHR) in homogeneous charge compression ignition (HCCI) engines using blends of ethanol and n-heptane. Experiments were performed over the range of 0-50% n-heptane liquid volume fractions, at equivalence ratios 0.4 and 0.5, and intake pressures from 1.4bar to 2.2bar. ITHR was induced in the mixtures containing predominantly ethanol through the addition of small amounts of n-heptane. After a critical threshold, additional n-heptane content yielded low temperature heat release (LTHR). A method for quantifying the amount of heat released during ITHR was developed by examining the second derivative of heat release, and this method was then used to identify trends in the engine data. The combustion process inside the engine was modeled using a single-zone HCCI model, and good qualitative agreement of pre-ignition pressure rise and heat release rate was found between experimental and modeling results using a detailed n-heptane/ethanol chemical kinetic model. The simulation results were used to identify the dominant reaction pathways contributing to ITHR, as well as to verify the chemical basis behind the quantification of the amount of ITHR in the experimental analysis. The dominant reaction pathways contributing to ITHR were found to be H-atom abstraction from n-heptane by OH and the addition of fuel radicals to O2. © 2013 The Combustion Institute.

  1. Concrete release protocol case studies for decommissioning work at the Idaho National Engineering and Environmental Laboratory

    International Nuclear Information System (INIS)

    Kamboj, S.; Arnish, J.; Chen, S-Y; Parker, F. L.; Phillips, A. M.; Tripp, J. L.; Meservey, R. H.

    2000-01-01

    The US Department of Energy (DOE) Order 5400.5, ''Radiation Protection of the Public and Environment'' contains provisions pertinent to releasing potentially radioactive materials from DOE facilities for reuse or recycle. A process of authorized release for materials recovered from radiation areas is permitted under Order 5400.5 and the proposed rule in Title 10, Part 834, of the Code of Federal Regulations (10 CFR Part 834). A generic disposition protocol to facilitate release of concrete under these provisions has been developed. This report analyzes the application of that generic protocol to site-specific cases at the Idaho National Engineering and Environmental Laboratory (INEEL). The potential radiological doses and costs for several concrete disposition alternatives for the sewage treatment plant (STP) at the Central Facilities Area (CFA) of INEEL were evaluated in this analysis. Five disposition alternatives were analyzed for the concrete: (A) decontaminate, crush, and reuse; (B) crush and reuse without decontamination; (C) decontaminate, demolish, and dispose of at a nonradiological landfill; (D) demolish and dispose of at a nonradiological landfill without decontamination; and (E) demolish and dispose of at a low-level radioactive waste (LLW) facility. The analysis was performed for disposition of concrete from four INEEL structures: (1) trickle filter, (2) primary clarifier, (3) secondary clarifier, and (4) CFA-691 pumphouse for a generic case (based on default parameters from the disposition protocol) and an INEEL-specific case (based on INEEL-specific parameters). The results of the analysis indicated that Alternatives B and D would incur the lowest cost and result in a dose less than 1 mrem/yr (except for the trickle filter, the dose for which was estimated at 1.9 mrem/yr) for nonradiological workers. The analysis indicated that the main contributor to the radiological dose would be cobalt-60 contamination in the concrete. A characterization conducted

  2. Modelling the effect of injection pressure on heat release parameters and nitrogen oxides in direct injection diesel engines

    Directory of Open Access Journals (Sweden)

    Yüksek Levent

    2014-01-01

    Full Text Available Investigation and modelling the effect of injection pressure on heat release parameters and engine-out nitrogen oxides are the main aim of this study. A zero-dimensional and multi-zone cylinder model was developed for estimation of the effect of injection pressure rise on performance parameters of diesel engine. Double-Wiebe rate of heat release global model was used to describe fuel combustion. extended Zeldovich mechanism and partial equilibrium approach were used for modelling the formation of nitrogen oxides. Single cylinder, high pressure direct injection, electronically controlled, research engine bench was used for model calibration. 1000 and 1200 bars of fuel injection pressure were investigated while injection advance, injected fuel quantity and engine speed kept constant. The ignition delay of injected fuel reduced 0.4 crank angle with 1200 bars of injection pressure and similar effect observed in premixed combustion phase duration which reduced 0.2 crank angle. Rate of heat release of premixed combustion phase increased 1.75 % with 1200 bar injection pressure. Multi-zone cylinder model showed good agreement with experimental in-cylinder pressure data. Also it was seen that the NOx formation model greatly predicted the engine-out NOx emissions for both of the operation modes.

  3. Fabrication and characterization of a rapid prototyped tissue engineering scaffold with embedded multicomponent matrix for controlled drug release

    Directory of Open Access Journals (Sweden)

    Chen M

    2012-08-01

    Full Text Available Muwan Chen,1,2 Dang QS Le,1,2 San Hein,2 Pengcheng Li,1 Jens V Nygaard,2 Moustapha Kassem,3 Jørgen Kjems,2 Flemming Besenbacher,2 Cody Bünger11Orthopaedic Research Lab, Aarhus University Hospital, Aarhus C, Denmark; 2Interdisciplinary Nanoscience Center (iNANO, Aarhus University, Aarhus C, Denmark; 3Department of Endocrinology and Metabolism, Odense University Hospital, Odense C, DenmarkAbstract: Bone tissue engineering implants with sustained local drug delivery provide an opportunity for better postoperative care for bone tumor patients because these implants offer sustained drug release at the tumor site and reduce systemic side effects. A rapid prototyped macroporous polycaprolactone scaffold was embedded with a porous matrix composed of chitosan, nanoclay, and β-tricalcium phosphate by freeze-drying. This composite scaffold was evaluated on its ability to deliver an anthracycline antibiotic and to promote formation of mineralized matrix in vitro. Scanning electronic microscopy, confocal imaging, and DNA quantification confirmed that immortalized human bone marrow-derived mesenchymal stem cells (hMSC-TERT cultured in the scaffold showed high cell viability and growth, and good cell infiltration to the pores of the scaffold. Alkaline phosphatase activity and osteocalcin staining showed that the scaffold was osteoinductive. The drug-release kinetics was investigated by loading doxorubicin into the scaffold. The scaffolds comprising nanoclay released up to 45% of the drug for up to 2 months, while the scaffold without nanoclay released 95% of the drug within 4 days. Therefore, this scaffold can fulfill the requirements for both bone tissue engineering and local sustained release of an anticancer drug in vitro. These results suggest that the scaffold can be used clinically in reconstructive surgery after bone tumor resection. Moreover, by changing the composition and amount of individual components, the scaffold can find application in other

  4. Microorganisms in food technology

    Energy Technology Data Exchange (ETDEWEB)

    Rose, A H

    1981-11-01

    Man has been using microorganisms for thousands of years to make bread, cheese, beer, wine, etc. Today, microorganisms can be specially grown or genetically manipulated so as to synthesize high-quality proteins even from low-grade basic materials.

  5. Thermophilic microorganisms in biomining.

    Science.gov (United States)

    Donati, Edgardo Rubén; Castro, Camila; Urbieta, María Sofía

    2016-11-01

    Biomining is an applied biotechnology for mineral processing and metal extraction from ores and concentrates. This alternative technology for recovering metals involves the hydrometallurgical processes known as bioleaching and biooxidation where the metal is directly solubilized or released from the matrix for further solubilization, respectively. Several commercial applications of biomining can be found around the world to recover mainly copper and gold but also other metals; most of them are operating at temperatures below 40-50 °C using mesophilic and moderate thermophilic microorganisms. Although biomining offers an economically viable and cleaner option, its share of the world´s production of metals has not grown as much as it was expected, mainly considering that due to environmental restrictions in many countries smelting and roasting technologies are being eliminated. The slow rate of biomining processes is for sure the main reason of their poor implementation. In this scenario the use of thermophiles could be advantageous because higher operational temperature would increase the rate of the process and in addition it would eliminate the energy input for cooling the system (bioleaching reactions are exothermic causing a serious temperature increase in bioreactors and inside heaps that adversely affects most of the mesophilic microorganisms) and it would decrease the passivation of mineral surfaces. In the last few years many thermophilic bacteria and archaea have been isolated, characterized, and even used for extracting metals. This paper reviews the current status of biomining using thermophiles, describes the main characteristics of thermophilic biominers and discusses the future for this biotechnology.

  6. Utilisation of VOC in Diesel Engines. Ignition and combustion of VOC released in crude oil tankers

    International Nuclear Information System (INIS)

    Melhus, Oeyvin

    2002-01-01

    the radiation of visible light from the diffusion combustion of diesel oil and VOC Fuel (i.e. propane, iso-butane and n-butane) are quite different. First, this radiation disturbs the Schlieren image and second, the radiation from the combustion of diesel oil is far more intense than that of the VOC Fuel. The light VOC fraction of the vent gas - methane and ethane - is not utilised in the concept of ''Condensate Diesel Process''. This fraction represents about 15 % of the total energy in the VOC release when loading crude oil at the Statfjord field. At other fields as Gullfaks, this fraction can represent up to 50% or more of the total energy. After the VOC Fuel is produced, a residual VOC consisting of methane, ethane, some propane and inert gas is lost. A useful and simple way of utilising even this fraction is to mix it with the charge air at low pressure and feed the mixture into the cylinder where a pilot fuel spray ignites the charge. The method is found to have potential of being a suitable way, at least theoretically, to utilise the light VOC fraction. Some practical difficulties, however, may restrict the use of this fraction to medium and high engine loads. At lower loads the ignition delay increases due to the dilution with great quantities of inert gas. Another option to utilise the light VOC fraction is by capturing the gas in hydrates. No real study of this concept has been carried out, but an initial survey of possible solutions is described. A final conclusion of the potential of this concept cannot be drawn until more detailed work has been carried out. However, simply using the light VOC fraction extracted by melting the hydrate will be the most likely way. As a main conclusion it can be stated that the use of VOC Fuel in a ''Condensate Diesel Process'' is a feasible way of utilising energy otherwise lost

  7. Size-fractionated characterization and quantification of nanoparticle release rates from a consumer spray product containing engineered nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Hagendorfer, Harald, E-mail: Harald.Hagendorfer@empa.c [EMPA, Swiss Federal Laboratories for Materials Testing and Research (Switzerland); Lorenz, Christiane, E-mail: Christiane.Lorenz@chem.ethz.c [ETHZ, Swiss Federal Institute of Technology Zurich (Switzerland); Kaegi, Ralf, E-mail: Ralf.Kaegi@eawag.ch; Sinnet, Brian, E-mail: Brian.Sinnet@eawag.c [EAWAG, Swiss Federal Institute of Aquatic Science and Technology (Switzerland); Gehrig, Robert, E-mail: Robert.Gehrig@empa.c [EMPA, Swiss Federal Laboratories for Materials Testing and Research (Switzerland); Goetz, Natalie V., E-mail: Natalie.vonGoetz@chem.ethz.ch; Scheringer, Martin, E-mail: Martin.Scheringer@chem.ethz.c [ETHZ, Swiss Federal Institute of Technology Zurich (Switzerland); Ludwig, Christian, E-mail: Christian.Ludwig@psi.c [PSI, Paul Scherrer Institue (Switzerland); Ulrich, Andrea, E-mail: Andrea.Ulrich@empa.c [EMPA, Swiss Federal Laboratories for Materials Testing and Research (Switzerland)

    2010-09-15

    This study describes methods developed for reliable quantification of size- and element-specific release of engineered nanoparticles (ENP) from consumer spray products. A modified glove box setup was designed to allow controlled spray experiments in a particle-minimized environment. Time dependence of the particle size distribution in a size range of 10-500 nm and ENP release rates were studied using a scanning mobility particle sizer (SMPS). In parallel, the aerosol was transferred to a size-calibrated electrostatic TEM sampler. The deposited particles were investigated using electron microscopy techniques in combination with image processing software. This approach enables the chemical and morphological characterization as well as quantification of released nanoparticles from a spray product. The differentiation of solid ENP from the released nano-sized droplets was achieved by applying a thermo-desorbing unit. After optimization, the setup was applied to investigate different spray situations using both pump and gas propellant spray dispensers for a commercially available water-based nano-silver spray. The pump spray situation showed no measurable nanoparticle release, whereas in the case of the gas spray, a significant release was observed. From the results it can be assumed that the homogeneously distributed ENP from the original dispersion grow in size and change morphology during and after the spray process but still exist as nanometer particles of size <100 nm. Furthermore, it seems that the release of ENP correlates with the generated aerosol droplet size distribution produced by the spray vessel type used. This is the first study presenting results concerning the release of ENP from spray products.

  8. Size-fractionated characterization and quantification of nanoparticle release rates from a consumer spray product containing engineered nanoparticles

    International Nuclear Information System (INIS)

    Hagendorfer, Harald; Lorenz, Christiane; Kaegi, Ralf; Sinnet, Brian; Gehrig, Robert; Goetz, Natalie V.; Scheringer, Martin; Ludwig, Christian; Ulrich, Andrea

    2010-01-01

    This study describes methods developed for reliable quantification of size- and element-specific release of engineered nanoparticles (ENP) from consumer spray products. A modified glove box setup was designed to allow controlled spray experiments in a particle-minimized environment. Time dependence of the particle size distribution in a size range of 10-500 nm and ENP release rates were studied using a scanning mobility particle sizer (SMPS). In parallel, the aerosol was transferred to a size-calibrated electrostatic TEM sampler. The deposited particles were investigated using electron microscopy techniques in combination with image processing software. This approach enables the chemical and morphological characterization as well as quantification of released nanoparticles from a spray product. The differentiation of solid ENP from the released nano-sized droplets was achieved by applying a thermo-desorbing unit. After optimization, the setup was applied to investigate different spray situations using both pump and gas propellant spray dispensers for a commercially available water-based nano-silver spray. The pump spray situation showed no measurable nanoparticle release, whereas in the case of the gas spray, a significant release was observed. From the results it can be assumed that the homogeneously distributed ENP from the original dispersion grow in size and change morphology during and after the spray process but still exist as nanometer particles of size <100 nm. Furthermore, it seems that the release of ENP correlates with the generated aerosol droplet size distribution produced by the spray vessel type used. This is the first study presenting results concerning the release of ENP from spray products.

  9. Cylinder pressure, performance parameters, heat release, specific heats ratio and duration of combustion for spark ignition engine

    International Nuclear Information System (INIS)

    Shehata, M.S.

    2010-01-01

    An experimental work were conducted for investigating cylinder pressure, performance parameters, heat release, specific heat ratio and duration of combustion for multi cylinder spark ignition engine (SIE). Ccylinder pressure was measured for gasoline, kerosene and Liquefied Petroleum Gases (LPG) separately as a fuel for SIE. Fast Fourier Transformations (FFT) was used to cylinder pressure data transform from time domain into frequency domain to develop empirical correlation for calculating cylinder pressures at different engine speeds and different fuels. In addition, Inverse Fast Fourier Transformations (IFFT) was used to cylinder pressure reconstruct into time domain. The results gave good agreement between the measured cylinder pressure and the reconstructed cylinder pressure in time domain with different engine speeds and different fuels. The measured cylinder pressure and hydraulic dynamotor were the sours of data for calculating engine performance parameters. First law of thermodynamics and single zone heat release model with temperature dependant specific heat ratio γ(T) were the main tools for calculating heat release and heat transfer to cylinder walls. Third order empirical correlation for calculating γ(T) was one of the main gains of the present study. The correlation gave good agreement with other researchers with wide temperatures range. For kerosene, cylinder pressure is higher than for gasoline and LPG due to high volumetric efficiency where kerosene density (mass/volume ratio) is higher than gasoline and LPG. In addition, kerosene heating value is higher than gasoline that contributes in heat release rate and pressure increases. Duration of combustion for different engine speeds was determined using four different methods: (I) Mass fuel burnt, (II) Entropy change, (III) Temperature dependant specific heat ratio γ(T), and (IV) Logarithmic scale of (P and V). The duration of combustion for kerosene is smaller than for gasoline and LPG due to high

  10. Cylinder pressure, performance parameters, heat release, specific heats ratio and duration of combustion for spark ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Shehata, M.S. [Mechanical Engineering Technology Department, Higher Institute of Technology, Banha University, 4Zagalol Street, Benha, Galubia 1235 Z (Egypt)

    2010-12-15

    An experimental work were conducted for investigating cylinder pressure, performance parameters, heat release, specific heat ratio and duration of combustion for multi cylinder spark ignition engine (SIE). Ccylinder pressure was measured for gasoline, kerosene and Liquefied Petroleum Gases (LPG) separately as a fuel for SIE. Fast Fourier Transformations (FFT) was used to cylinder pressure data transform from time domain into frequency domain to develop empirical correlation for calculating cylinder pressures at different engine speeds and different fuels. In addition, Inverse Fast Fourier Transformations (IFFT) was used to cylinder pressure reconstruct into time domain. The results gave good agreement between the measured cylinder pressure and the reconstructed cylinder pressure in time domain with different engine speeds and different fuels. The measured cylinder pressure and hydraulic dynamotor were the source of data for calculating engine performance parameters. First law of thermodynamics and single zone heat release model with temperature dependant specific heat ratio {gamma}(T) were the main tools for calculating heat release and heat transfer to cylinder walls. Third order empirical correlation for calculating {gamma}(T) was one of the main gains of the present study. The correlation gave good agreement with other researchers with wide temperatures range. For kerosene, cylinder pressure is higher than for gasoline and LPG due to high volumetric efficiency where kerosene density (mass/volume ratio) is higher than gasoline and LPG. In addition, kerosene heating value is higher than gasoline that contributes in heat release rate and pressure increases. Duration of combustion for different engine speeds was determined using four different methods: (I) Mass fuel burnt, (II) Entropy change, (III) Temperature dependant specific heat ratio {gamma}(T), and (IV) Logarithmic scale of (P and V). The duration of combustion for kerosene is smaller than for gasoline and

  11. Modified n-HA/PA66 scaffolds with chitosan coating for bone tissue engineering: cell stimulation and drug release.

    Science.gov (United States)

    Zou, Qin; Li, Junfeng; Niu, Lulu; Zuo, Yi; Li, Jidong; Li, Yubao

    2017-09-01

    The dipping-drying procedure and cross-linking method were used to make drug-loaded chitosan (CS) coating on nano-hydroxyapatite/polyamide66 (nHA/PA66) composite porous scaffold, endowing the scaffold controlled drug release functionality. The prefabricated scaffold was immersed into an aqueous drug/CS solution in a vacuum condition and then crosslinked by vanillin. The structure, porosity, composition, compressive strength, swelling ratio, drug release and cytocompatibility of the pristine and coating scaffolds were investigated. After coating, the scaffold porosity and pore interconnection were slightly decreased. Cytocompatibility performance was observed through an in vitro experiment based on cell attachment and the MTT assay by MG63 cells which revealed positive cell viability and increasing proliferation over the 11-day period in vitro. The drug could effectively release from the coated scaffold in a controlled fashion and the release rate was sustained for a long period and highly dependent on coating swelling, suggesting the possibility of a controlled drug release. Our results demonstrate that the scaffold with drug-loaded crosslinked CS coating can be used as a simple technique to render the surfaces of synthetic scaffolds active, thus enabling them to be a promising high performance biomaterial in bone tissue engineering.

  12. Microorganisms as sources of oils

    Directory of Open Access Journals (Sweden)

    Thevenieau France

    2013-11-01

    Full Text Available A number of microorganism belonging to the genera of yeast, fungi, bacteria and microalgae have ability to accumulate substantial amounts of oil, sometimes up to an even in excess of 70% of their biomass weight under specific cultivation conditions. For nearly 100 years, the commercial opportunities of using microorganisms as sources of oils have been continuously examined. Although it was evident that microbial oils could never compete commercially with the major commodity plant oils, there were commercially opportunities for the production of some of the higher valued oils. Today, with the great progress of metabolic and genetic engineering, the developments are focus on the high value oils containing important polyunsaturated or specific fatty acids. Such oils have the potential to be used in different applications area as food, feed and oleochemistry. This review is covering the related researches about different oleaginous microorganisms for lipids production and microbial oils biosynthesis process. In add, the lipid metabolism, metabolic engineering strategies to increase lipid production and the economics of microbial oils production are introduced.

  13. Controllable mineral coatings on scaffolds as carriers for growth factor release for bone tissue engineering

    Science.gov (United States)

    Saurez-Gonzalez, Darilis

    The work presented in this document, focused on the development and characterization of mineral coatings on scaffold materials to serve as templates for growth factor binding and release. Mineral coatings were formed using a biomimetic approach that consisted in the incubation of scaffolds in modified simulated body fluids (mSBF). To modulate the properties of the mineral coating, which we hypothesized would dictate growth factor release, we used carbonate (HCO3) concentration in mSBF of 4.2 mM, 25mM, and 100mM. Analysis of the mineral coatings formed using scanning electron microscopy indicated growth of a continuous layer of mineral with different morphologies. X-ray diffraction analysis showed peaks associated with hydroxyapatite. FTIR data confirmed the substitution of HCO3 in the mineral. As the extent of HCO3 substitution increased, the coating exhibited more rapid dissolution kinetics in an environment deficient in calcium and phosphate. The mineral coatings provided an effective mechanism for bioactive growth factor binding and release. Peptide versions of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP2) were bound with efficiencies up to 90% to mineral-coated PCL scaffolds. Recombinant human vascular endothelial growth factor (rhVEGF) also bound to mineral coated scaffolds with lower efficiency (20%) and released with faster release kinetics compared to peptides growth factor. Released rhVEGF induced human umbilical vein endothelial cell (HUVEC) proliferation in vitro and enhanced blood vessel formation in vivo in an intramuscular sheep model. In addition to the use the mineral coatings for single growth factor release, we expanded the concept and bound both an angiogenic (rhVEGF) and osteogenic (mBMP2) growth factor by a simple double dipping process. Sustained release of both growth factors was demonstrated for over 60 days. Released rhVEGF enhanced blood vessel formation in vivo in sheep and its biological activity was

  14. An Fc engineering approach that modulates antibody-dependent cytokine release without altering cell-killing functions.

    Science.gov (United States)

    Kinder, Michelle; Greenplate, Allison R; Strohl, William R; Jordan, Robert E; Brezski, Randall J

    2015-01-01

    Cytotoxic therapeutic monoclonal antibodies (mAbs) often mediate target cell-killing by eliciting immune effector functions via Fc region interactions with cellular and humoral components of the immune system. Key functions include antibody-dependent cell-mediated cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and complement-dependent cytotoxicity (CDC). However, there has been increased appreciation that along with cell-killing functions, the induction of antibody-dependent cytokine release (ADCR) can also influence disease microenvironments and therapeutic outcomes. Historically, most Fc engineering approaches have been aimed toward modulating ADCC, ADCP, or CDC. In the present study, we describe an Fc engineering approach that, while not resulting in impaired ADCC or ADCP, profoundly affects ADCR. As such, when peripheral blood mononuclear cells are used as effector cells against mAb-opsonized tumor cells, the described mAb variants elicit a similar profile and quantity of cytokines as IgG1. In contrast, although the variants elicit similar levels of tumor cell-killing as IgG1 with macrophage effector cells, the variants do not elicit macrophage-mediated ADCR against mAb-opsonized tumor cells. This study demonstrates that Fc engineering approaches can be employed to uncouple macrophage-mediated phagocytic and subsequent cell-killing functions from cytokine release.

  15. Characterization of nanoparticles released during construction of photocatalytic pavements using engineered nanoparticles

    International Nuclear Information System (INIS)

    Dylla, Heather; Hassan, Marwa M.

    2012-01-01

    With the increasing use of titanium dioxide (TiO 2 ) nanoparticles in self-cleaning materials such as photocatalytic concrete pavements, the release of nanoparticles into the environment is inevitable. Nanoparticle concentration, particle size, surface area, elemental composition, and surface morphology are pertinent to determine the associated risks. In this study, the potential of exposure to synthetic nanoparticles released during construction activities for application of photocatalytic pavements was measured during laboratory-simulated construction activities of photocatalytic mortar overlays and in an actual field application of photocatalytic spray coat. A scanning mobility particle sizer system measured the size distribution of nanoparticles released during laboratory and field activities. Since incidental nanoparticles are released during construction activities, nanoparticle emissions were compared to those from similar activities without nano-TiO 2 . Nanoparticle counts and size distribution suggest that synthetic nanoparticles are released during application of photocatalytic pavements. In order to identify the nanoparticle source, nanoparticles were also collected for offline characterization using transmission electron microscopy. However, positive identification of synthetic nanoparticles was not possible due to difficulties in obtaining high-resolution images. As a result, further research is recommended to identify nanoparticle composition and sources.

  16. Functional microorganisms for functional food quality.

    Science.gov (United States)

    Gobbetti, M; Cagno, R Di; De Angelis, M

    2010-09-01

    Functional microorganisms and health benefits represent a binomial with great potential for fermented functional foods. The health benefits of fermented functional foods are expressed either directly through the interactions of ingested live microorganisms with the host (probiotic effect) or indirectly as the result of the ingestion of microbial metabolites synthesized during fermentation (biogenic effect). Since the importance of high viability for probiotic effect, two major options are currently pursued for improving it--to enhance bacterial stress response and to use alternative products for incorporating probiotics (e.g., ice cream, cheeses, cereals, fruit juices, vegetables, and soy beans). Further, it seems that quorum sensing signal molecules released by probiotics may interact with human epithelial cells from intestine thus modulating several physiological functions. Under optimal processing conditions, functional microorganisms contribute to food functionality through their enzyme portfolio and the release of metabolites. Overproduction of free amino acids and vitamins are two classical examples. Besides, bioactive compounds (e.g., peptides, γ-amino butyric acid, and conjugated linoleic acid) may be released during food processing above the physiological threshold and they may exert various in vivo health benefits. Functional microorganisms are even more used in novel strategies for decreasing phenomenon of food intolerance (e.g., gluten intolerance) and allergy. By a critical approach, this review will aim at showing the potential of functional microorganisms for the quality of functional foods.

  17. Biosurfactants from marine microorganisms

    Directory of Open Access Journals (Sweden)

    Suppasil Maneerat

    2005-11-01

    Full Text Available Biosurfactants are the surface-active molecules synthesized by microorganisms. With the advantage of environmental compatibility, the demand for biosurfactants has been steadily increasing and may eventually replace their chemically synthesized counterparts. Marine biosurfactants produced by some marine microorganisms have been paid more attention, particularly for the bioremediation of the sea polluted by crude oil. This review describes screening of biosurfactant-producing microorganisms, the determination of biosurfactant activity as well as the recovery of marine surfactant. The uses of marine biosurfactants for bioremediation are also discussed.

  18. Tissue-engineered matrices as functional delivery systems: adsorption and release of bioactive proteins from degradable composite scaffolds.

    Science.gov (United States)

    Cushnie, Emily K; Khan, Yusuf M; Laurencin, Cato T

    2010-08-01

    A tissue-engineered bone graft should imitate the ideal autograft in both form and function. However, biomaterials that have appropriate chemical and mechanical properties for grafting applications often lack biological components that may enhance regeneration. The concept of adding proteins such as growth factors to scaffolds has therefore emerged as a possible solution to improve overall graft design. In this study, we investigated this concept by loading porous hydroxyapatite-poly(lactide-co-glycolide) (HA-PLAGA) scaffolds with a model protein, cytochrome c, and then studying its release in a phosphate-buffered saline solution. The HA-PLAGA scaffold has previously been shown to be bioactive, osteoconductive, and to have appropriate physical properties for tissue engineering applications. The loading experiments demonstrated that the HA-PLAGA scaffold could also function effectively as a substrate for protein adsorption and release. Scaffold protein adsorptive loading (as opposed to physical entrapment within the matrix) was directly related to levels of scaffold HA-content. The HA phase of the scaffold facilitated protein retention in the matrix following incubation in aqueous buffer for periods up to 8 weeks. Greater levels of protein retention time may improve the protein's effective activity by increasing the probability for protein-cell interactions. The ability to control protein loading and delivery simply via composition of the HA-PLAGA scaffold offers the potential of forming robust functionalized bone grafts. (c) 2010 Wiley Periodicals, Inc.

  19. Effect of Engineered Nanoparticles on Exopolymeric Substances Release from Marine Phytoplankton

    OpenAIRE

    Chiu, Meng-Hsuen; Khan, Zafir A.; Garcia, Santiago G.; Le, Andre D.; Kagiri, Agnes; Ramos, Javier; Tsai, Shih-Ming; Drobenaire, Hunter W.; Santschi, Peter H.; Quigg, Antonietta; Chin, Wei-Chun

    2017-01-01

    Engineered nanoparticles (ENPs), products from modern nanotechnologies, can potentially impact the marine environment to pose serious threats to marine ecosystems. However, the cellular responses of marine phytoplankton to ENPs are still not well established. Here, we investigate four different diatom species (Odontella mobiliensis, Skeletonema grethae, Phaeodactylum tricornutum, Thalassiosira pseudonana) and one green algae (Dunaliella tertiolecta) for their extracellular polymeric substance...

  20. Using mass-release of engineered insects to manage insecticide resistance

    International Nuclear Information System (INIS)

    Alphey, Nina; Coleman, Paul G.; Donnelly, Christl A.

    2006-01-01

    Transgenic crops expressing insecticidal toxins derived from Bacillus thuringiensis (Bt) are widely used to control insect pests. The benefits of such crops would be lost if resistance to the toxins spread to a significant proportion of the pest population. The main resistance management method, mandatory in the US, is the high-dose/refuge strategy, requiring nearby refuges of toxin-free crops, and the use of toxin doses sufficiently high to kill not only wild type insects but also insects heterozygous for a resistance allele, thereby rendering the resistance functionally recessive. We propose that mass-release of harmless toxin-sensitive insects could substantially delay or even reverse the spread of resistance. Mass-release of such insects is an integral part of RIDL, a genetics-based method of pest control related to the Sterile Insect Technique. We used a population genetic mathematical model to analyze the effects of releasing male insects homozygous for a female-specific dominant lethal genetic construct, and concluded that this RIDL strategy could form an effective component of a resistance management scheme for insecticidal plants and other toxins. (author)

  1. Using mass-release of engineered insects to manage insecticide resistance

    Energy Technology Data Exchange (ETDEWEB)

    Alphey, Nina [University of Oxford (United Kingdom). Dept. of Zoology; Alphey, Luke [Oxitec Limited, Oxford (United Kingdom); Coleman, Paul G [London School of Hygiene and Tropical Medicine (United Kingdom). Dept. of Infectious and Tropical Diseases; Donnelly, Christl A [Imperial College Faculty of Medicine, London (United Kingdom). Dept. of Infectious Disease Epidemiology

    2006-07-01

    Transgenic crops expressing insecticidal toxins derived from Bacillus thuringiensis (Bt) are widely used to control insect pests. The benefits of such crops would be lost if resistance to the toxins spread to a significant proportion of the pest population. The main resistance management method, mandatory in the US, is the high-dose/refuge strategy, requiring nearby refuges of toxin-free crops, and the use of toxin doses sufficiently high to kill not only wild type insects but also insects heterozygous for a resistance allele, thereby rendering the resistance functionally recessive. We propose that mass-release of harmless toxin-sensitive insects could substantially delay or even reverse the spread of resistance. Mass-release of such insects is an integral part of RIDL, a genetics-based method of pest control related to the Sterile Insect Technique. We used a population genetic mathematical model to analyze the effects of releasing male insects homozygous for a female-specific dominant lethal genetic construct, and concluded that this RIDL strategy could form an effective component of a resistance management scheme for insecticidal plants and other toxins. (author)

  2. Biodegradable hyaluronic acid hydrogels to control release of dexamethasone through aqueous Diels–Alder chemistry for adipose tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Ming; Ma, Ye; Zhang, Ziwei; Mao, Jiahui [School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing (China); Tan, Huaping, E-mail: hptan@njust.edu.cn [School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing (China); Hu, Xiaohong [School of Material Engineering, Jinling Institute of Technology, Nanjing (China)

    2015-11-01

    A robust synthetic strategy of biopolymer-based hydrogels has been developed where hyaluronic acid derivatives reacted through aqueous Diels–Alder chemistry without the involvement of chemical catalysts, allowing for control and sustain release of dexamethasone. To conjugate the hydrogel, furan and maleimide functionalized hyaluronic acid were synthesized, respectively, as well as furan functionalized dexamethasone, for the covalent immobilization. Chemical structure, gelation time, morphologies, swelling kinetics, weight loss, compressive modulus and dexamethasone release of the hydrogel system in PBS at 37 °C were studied. The results demonstrated that the aqueous Diels–Alder chemistry provides an extremely selective reaction and proceeds with high efficiency for hydrogel conjugation and covalent immobilization of dexamethasone. Cell culture results showed that the dexamethasone immobilized hydrogel was noncytotoxic and preserved proliferation of entrapped human adipose-derived stem cells. This synthetic approach uniquely allows for the direct fabrication of biologically functionalized gel scaffolds with ideal structures for adipose tissue engineering, which provides a competitive alternative to conventional conjugation techniques such as copper mediated click chemistry. - Highlights: • A biodegradable hyaluronic acid hydrogel was crosslinked via aqueous Diels–Alder chemistry. • Dexamethasone was covalently immobilized into the hyaluronic acid hydrogel via aqueous Diels–Alder chemistry. • Dexamethasone could be released from the Diels–Alder hyaluronic acid hydrogel in a controlled fashion.

  3. Biodegradable hyaluronic acid hydrogels to control release of dexamethasone through aqueous Diels–Alder chemistry for adipose tissue engineering

    International Nuclear Information System (INIS)

    Fan, Ming; Ma, Ye; Zhang, Ziwei; Mao, Jiahui; Tan, Huaping; Hu, Xiaohong

    2015-01-01

    A robust synthetic strategy of biopolymer-based hydrogels has been developed where hyaluronic acid derivatives reacted through aqueous Diels–Alder chemistry without the involvement of chemical catalysts, allowing for control and sustain release of dexamethasone. To conjugate the hydrogel, furan and maleimide functionalized hyaluronic acid were synthesized, respectively, as well as furan functionalized dexamethasone, for the covalent immobilization. Chemical structure, gelation time, morphologies, swelling kinetics, weight loss, compressive modulus and dexamethasone release of the hydrogel system in PBS at 37 °C were studied. The results demonstrated that the aqueous Diels–Alder chemistry provides an extremely selective reaction and proceeds with high efficiency for hydrogel conjugation and covalent immobilization of dexamethasone. Cell culture results showed that the dexamethasone immobilized hydrogel was noncytotoxic and preserved proliferation of entrapped human adipose-derived stem cells. This synthetic approach uniquely allows for the direct fabrication of biologically functionalized gel scaffolds with ideal structures for adipose tissue engineering, which provides a competitive alternative to conventional conjugation techniques such as copper mediated click chemistry. - Highlights: • A biodegradable hyaluronic acid hydrogel was crosslinked via aqueous Diels–Alder chemistry. • Dexamethasone was covalently immobilized into the hyaluronic acid hydrogel via aqueous Diels–Alder chemistry. • Dexamethasone could be released from the Diels–Alder hyaluronic acid hydrogel in a controlled fashion

  4. Microorganisms involved in MIC

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, K. [Danish Technological Institute (Denmark)

    2011-07-01

    Microbiologically influenced corrosion (MIC) is a widespread problem that is difficult to detect and assess because of its complex mechanism. This paper presents the involvement of microorganisms in MIC. Some of the mechanisms that cause MIC include hydrogen consumption, production of acids, anode-cathode formation and electron shuttling. A classic bio-corrosive microorganism in the oil and gas industry is sulphate-reducing prokaryotes (SRP). Methanogens also increase corrosion rates in metals. Some of the phylogenetic orders detected while studying SRP and methanogens are archaeoglobales, clostridiales, methanosarcinales and methanothermococcus. There were some implications, such as growth of SRP not being correlated with growth of methanogens; methanogens were included in MIC risk assessment. A few examples are used to display how microorganisms are involved in topside corrosion and microbial community in producing wells. From the study, it can be concluded that, MIC risk assessment includes system data and empirical knowledge of the distribution and number of microorganisms in the system.

  5. Analysis of heat release dynamics in an internal combustion engine using multifractals and wavelets

    International Nuclear Information System (INIS)

    Sen, A.K.; Litak, G.; Finney, C.E.A.; Daw, C.S.; Wagner, R.M.

    2010-01-01

    In this paper we analyze data from previously reported experimental measurements of cycle-to-cycle combustion variations in a lean-fueled, multi-cylinder spark-ignition (SI) engine. We characterize the changes in the observed combustion dynamics with as-fed fuel-air ratio using conventional histograms and statistical moments, and we further characterize the shifts in combustion complexity in terms of multifractals and wavelet decomposition. Changes in the conventional statistics and multifractal structure indicate trends with fuel-air ratio that parallel earlier reported observations. Wavelet decompositions reveal persistent, non-stochastic oscillation modes at higher fuel-air ratios that were not obvious in previous analyses. Recognition of these long-time-scale, non-stochastic oscillations is expected to be useful for improving modelling and control of engine combustion variations and multi-cylinder balancing.

  6. Systems Biology of Industrial Microorganisms

    Science.gov (United States)

    Papini, Marta; Salazar, Margarita; Nielsen, Jens

    The field of industrial biotechnology is expanding rapidly as the chemical industry is looking towards more sustainable production of chemicals that can be used as fuels or building blocks for production of solvents and materials. In connection with the development of sustainable bioprocesses, it is a major challenge to design and develop efficient cell factories that can ensure cost efficient conversion of the raw material into the chemical of interest. This is achieved through metabolic engineering, where the metabolism of the cell factory is engineered such that there is an efficient conversion of sugars, the typical raw materials in the fermentation industry, into the desired product. However, engineering of cellular metabolism is often challenging due to the complex regulation that has evolved in connection with adaptation of the different microorganisms to their ecological niches. In order to map these regulatory structures and further de-regulate them, as well as identify ingenious metabolic engineering strategies that full-fill mass balance constraints, tools from systems biology can be applied. This involves both high-throughput analysis tools like transcriptome, proteome and metabolome analysis, as well as the use of mathematical modeling to simulate the phenotypes resulting from the different metabolic engineering strategies. It is in fact expected that systems biology may substantially improve the process of cell factory development, and we therefore propose the term Industrial Systems Biology for how systems biology will enhance the development of industrial biotechnology for sustainable chemical production.

  7. Spot the difference: engineered and natural nanoparticles in the environment--release, behavior, and fate.

    Science.gov (United States)

    Wagner, Stephan; Gondikas, Andreas; Neubauer, Elisabeth; Hofmann, Thilo; von der Kammer, Frank

    2014-11-10

    The production and use of nanoparticles leads to the emission of manufactured or engineered nanoparticles into the environment. Those particles undergo many possible reactions and interactions in the environment they are exposed to. These reactions and the resulting behavior and fate of nanoparticles in the environment have been studied for decades through naturally occurring nanoparticulate (1-100 nm) and colloidal (1-1000 nm) substances. The knowledge gained from these investigations is nowhere near sufficiently complete to create a detailed model of the behavior and fate of engineered nanoparticles in the environment, but is a valuable starting point for the risk assessment of these novel materials. It is the aim of this Review to critically compare naturally observed processes with those found for engineered systems to identify the "nanospecific" properties of manufactured particles and describe critical knowledge gaps relevant for the risk assessment of manufactured nanomaterials in the environment. © 2014 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution Non-Commercial NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

  8. Pathways and mechanisms for product release in the engineered haloalkane dehalogenases explored using classical and random acceleration molecular dynamics simulations.

    Science.gov (United States)

    Klvana, Martin; Pavlova, Martina; Koudelakova, Tana; Chaloupkova, Radka; Dvorak, Pavel; Prokop, Zbynek; Stsiapanava, Alena; Kuty, Michal; Kuta-Smatanova, Ivana; Dohnalek, Jan; Kulhanek, Petr; Wade, Rebecca C; Damborsky, Jiri

    2009-10-09

    Eight mutants of the DhaA haloalkane dehalogenase carrying mutations at the residues lining two tunnels, previously observed by protein X-ray crystallography, were constructed and biochemically characterized. The mutants showed distinct catalytic efficiencies with the halogenated substrate 1,2,3-trichloropropane. Release pathways for the two dehalogenation products, 2,3-dichloropropane-1-ol and the chloride ion, and exchange pathways for water molecules, were studied using classical and random acceleration molecular dynamics simulations. Five different pathways, denoted p1, p2a, p2b, p2c, and p3, were identified. The individual pathways showed differing selectivity for the products: the chloride ion releases solely through p1, whereas the alcohol releases through all five pathways. Water molecules play a crucial role for release of both products by breakage of their hydrogen-bonding interactions with the active-site residues and shielding the charged chloride ion during its passage through a hydrophobic tunnel. Exchange of the chloride ions, the alcohol product, and the waters between the buried active site and the bulk solvent can be realized by three different mechanisms: (i) passage through a permanent tunnel, (ii) passage through a transient tunnel, and (iii) migration through a protein matrix. We demonstrate that the accessibility of the pathways and the mechanisms of ligand exchange were modified by mutations. Insertion of bulky aromatic residues in the tunnel corresponding to pathway p1 leads to reduced accessibility to the ligands and a change in mechanism of opening from permanent to transient. We propose that engineering the accessibility of tunnels and the mechanisms of ligand exchange is a powerful strategy for modification of the functional properties of enzymes with buried active sites.

  9. Development and optimization of press coated tablets of release engineered valsartan for pulsatile delivery.

    Science.gov (United States)

    Shah, Sunny; Patel, Romik; Soniwala, Moinuddin; Chavda, Jayant

    2015-01-01

    The present work is aimed to develop and optimize pulsatile delivery during dissolution of an improved formulation of valsartan to coordinate the drug release with circadian rhythm. Preliminary studies suggested that β cyclodextrin could improve the solubility of valsartan and showed AL type solubility curve. A 1:1 stoichiometric ratio of valsartan to β cyclodextrin was revealed from phase solubility studies and Job's plot. The prepared complex showed significantly better dissolution efficiency (p valsartan β cyclodextrin complex was significantly higher (p valsartan β cyclodextrin complex were subsequently prepared and application of the Plackett-Burman screening design revealed that HPMC K4M and EC showed significant effect on lag time. A 3(2) full factorial design was used to measure the response of HPMC K4M and EC on lag time and time taken for 90% drug release (T90). The optimized batch prepared according to the levels obtained from the desirability function had a lag time of 6 h and consisted of HPMC K4M:ethylcellulose in a 1:1.5 ratio with 180 mg of coating and revealed a close agreement between observed and predicted value (R(2 )= 0.9694).

  10. Development of proposed free release criteria for Idaho National Engineering Laboratory lead

    International Nuclear Information System (INIS)

    Losinski, S.J.

    1994-01-01

    The INEL Lead Management Project (LMP) performed an investigation of the origin of lead used as shielding at the INEL and developed radiological profile information that was then used to establish a baseline for the DOE ''no-rad-added'' standard. Primary findings of the investigation include the following: (a) Much of the lead at the INEL was obtained from a DOE lead bank; (b) Lead inventory at the DOE lead bank was derived primarily from recycled sources and was most likely in the form of pure lead; (c) Secondary lead (lead from recycled sources), available in today's market, is expected to have radiological characteristics similar to those of the DOE lead bank; (d) Highly sensitive radiological testing of 20 samples of lead from secondary sources revealed the lead to be radiologically pristine. Beta-, gamma-, and alpha-emitting radionuclide concentrations were all found to be less than detectable, except for a very small quantity of lead-210 (an alpha emitter), which is a naturally occurring isotope of lead. Based on the pristine nature of lead, a proposed free release criterion for lead was developed based on a statistical null hypothesis approach. The free release criterion compares the natural background count of a clean lead standard with the natural background count of a sample. When the sample background count cannot be distinguished as different from the standard background count at the 95% confidence level, then the sample is considered radiologically clean

  11. Plant immunity triggered by engineered in vivo release of oligogalacturonides, damage-associated molecular patterns.

    Science.gov (United States)

    Benedetti, Manuel; Pontiggia, Daniela; Raggi, Sara; Cheng, Zhenyu; Scaloni, Flavio; Ferrari, Simone; Ausubel, Frederick M; Cervone, Felice; De Lorenzo, Giulia

    2015-04-28

    Oligogalacturonides (OGs) are fragments of pectin that activate plant innate immunity by functioning as damage-associated molecular patterns (DAMPs). We set out to test the hypothesis that OGs are generated in planta by partial inhibition of pathogen-encoded polygalacturonases (PGs). A gene encoding a fungal PG was fused with a gene encoding a plant polygalacturonase-inhibiting protein (PGIP) and expressed in transgenic Arabidopsis plants. We show that expression of the PGIP-PG chimera results in the in vivo production of OGs that can be detected by mass spectrometric analysis. Transgenic plants expressing the chimera under control of a pathogen-inducible promoter are more resistant to the phytopathogens Botrytis cinerea, Pectobacterium carotovorum, and Pseudomonas syringae. These data provide strong evidence for the hypothesis that OGs released in vivo act as a DAMP signal to trigger plant immunity and suggest that controlled release of these molecules upon infection may be a valuable tool to protect plants against infectious diseases. On the other hand, elevated levels of expression of the chimera cause the accumulation of salicylic acid, reduced growth, and eventually lead to plant death, consistent with the current notion that trade-off occurs between growth and defense.

  12. Sol-gel derived manganese-releasing bioactive glass as a therapeutical approach for bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Barrioni, B.R.; Oliveira, A.C.; Leite, M.F.; Pereira, M.M. [Universidade Federal de Minas Gerais (UFMG), MG (Brazil)

    2016-07-01

    Full text: Bioactive glasses (BG) have been highlighted in tissue engineering, due to their high bioactivity and biocompatibility, being potential materials for bone tissue repair. Its composition is variable and quite flexible, allowing the incorporation of therapeutic metallic ions, which has been regarded as a promising approach in the development of BG with superior properties for tissue engineering. These ions can be released in a controlled manner during the dissolution process of the glass, having the advantage of being released at the exactly implant site where they are needed, thus optimizing the therapeutic efficacy and reducing undesired side effects in the patient. Among several ions that have been studied, Manganese (Mn) has been shown to favor osteogenic differentiation. Besides, this ion is also a cofactor for several enzymes involved in remodeling of extracellular matrix, presenting an important role in cell adhesion. Therefore, it is very important to study the Mn role in the BG network and its influence on the glass bioactivity. In this context, new bioactive glass compositions derived from the 58S (60%SiO2-36%CaO-4%P2O5, mol%) were synthesized in this work, using the sol-gel method, by the incorporation of Mn into their structure. FTIR and Raman spectra showed the presence of typical BG chemical groups, whereas the amorphous structure typical of these materials was confirmed by XRD analysis, which also indicated that the Mn incorporation in the glass network was well succeeded, as its precursor did not recrystallize. The role of Mn in the glass network was also evaluated by XPS. The influence of Mn on carbonated hydroxyapatite layer formation after different periods of immersion of the BG powder in Simulated Body Fluid was evaluated using zeta potential, SEM, EDS and FTIR, whereas the controlled ion release was measured through ICP-OES. MTT assay revealed that Mn-containing BG showed no cytotoxic effect on cell culture. All these results indicate

  13. Sol-gel derived manganese-releasing bioactive glass as a therapeutical approach for bone tissue engineering

    International Nuclear Information System (INIS)

    Barrioni, B.R.; Oliveira, A.C.; Leite, M.F.; Pereira, M.M.

    2016-01-01

    Full text: Bioactive glasses (BG) have been highlighted in tissue engineering, due to their high bioactivity and biocompatibility, being potential materials for bone tissue repair. Its composition is variable and quite flexible, allowing the incorporation of therapeutic metallic ions, which has been regarded as a promising approach in the development of BG with superior properties for tissue engineering. These ions can be released in a controlled manner during the dissolution process of the glass, having the advantage of being released at the exactly implant site where they are needed, thus optimizing the therapeutic efficacy and reducing undesired side effects in the patient. Among several ions that have been studied, Manganese (Mn) has been shown to favor osteogenic differentiation. Besides, this ion is also a cofactor for several enzymes involved in remodeling of extracellular matrix, presenting an important role in cell adhesion. Therefore, it is very important to study the Mn role in the BG network and its influence on the glass bioactivity. In this context, new bioactive glass compositions derived from the 58S (60%SiO2-36%CaO-4%P2O5, mol%) were synthesized in this work, using the sol-gel method, by the incorporation of Mn into their structure. FTIR and Raman spectra showed the presence of typical BG chemical groups, whereas the amorphous structure typical of these materials was confirmed by XRD analysis, which also indicated that the Mn incorporation in the glass network was well succeeded, as its precursor did not recrystallize. The role of Mn in the glass network was also evaluated by XPS. The influence of Mn on carbonated hydroxyapatite layer formation after different periods of immersion of the BG powder in Simulated Body Fluid was evaluated using zeta potential, SEM, EDS and FTIR, whereas the controlled ion release was measured through ICP-OES. MTT assay revealed that Mn-containing BG showed no cytotoxic effect on cell culture. All these results indicate

  14. Microcapsule Technology for Controlled Growth Factor Release in Musculoskeletal Tissue Engineering.

    Science.gov (United States)

    Della Porta, Giovanna; Ciardulli, Maria C; Maffulli, Nicola

    2018-06-01

    Tissue engineering strategies have relied on engineered 3-dimensional (3D) scaffolds to provide architectural templates that can mimic the native cell environment. Among the several technologies proposed for the fabrication of 3D scaffold, that can be attractive for stem cell cultivation and differentiation, moulding or bioplotting of hydrogels allow the stratification of layers loaded with cells and with specific additives to obtain a predefined microstructural organization. Particularly with bioplotting technology, living cells, named bio-ink, and additives, such as biopolymer microdevices/nanodevices for the controlled delivery of growth factors or biosignals, can be organized spatially into a predesigned 3D pattern by automated fabrication with computer-aided digital files. The technologies for biopolymer microcarrier/nanocarrier fabrication can be strategic to provide a controlled spatiotemporal delivery of specific biosignals within a microenvironment that can better or faster address the stem cells loaded within it. In this review, some examples of growth factor-controlled delivery by biopolymer microdevices/nanodevices embedded within 3D hydrogel scaffolds will be described, to achieve a bioengineered 3D interactive microenvironment for stem cell differentiation. Conventional and recently proposed technologies for biopolymer microcapsule fabrication for controlled delivery over several days will also be illustrated and critically discussed.

  15. Sensitivity of the engineered barrier system (EBS) release rate to alternative conceptual models of advective release from waste packages under dripping fractures

    International Nuclear Information System (INIS)

    Lee, J.H.; Atkins, J.E.; McNeish, J.A.; Vallikat, V.

    1996-01-01

    The first model assumed that dripping water directly contacts the waste form inside the ''failed'' waste package and radionuclides are released from the EBS by advection. The second model assumed that dripping water is diverted around the package (because of corrosion products plugging the perforations), thereby being prevented from directly contacting the waste form. In the second model, radionuclides were assumed to diffuse through the perforations, and, once outside the waste package, to be released from the EBS by advection. For the case with the second EBS release model, most radionuclides had lower peak EBS release rates than with the first model. Impacts of the alternative EBS release models were greater for the radionuclides with low solubility. The analysis indicated that the EBS release model representing advection through a ''failed'' waste package (the first model) may be too conservative; thus a ''failed'' waste package container with multiple perforations may still be an important barrier to radionuclide release

  16. Fossil Microorganisms in Archaean

    Science.gov (United States)

    Astafleva, Marina; Hoover, Richard; Rozanov, Alexei; Vrevskiy, A.

    2006-01-01

    Ancient Archean and Proterozoic rocks are the model objects for investigation of rocks comprising astromaterials. The first of Archean fossil microorganisms from Baltic shield have been reported at the last SPIE Conference in 2005. Since this confeence biomorphic structures have been revealed in Archean rocks of Karelia. It was determined that there are 3 types of such bion structures: 1. structures found in situ, in other words microorganisms even-aged with rock matrix, that is real Archean fossils biomorphic structures, that is to say forms inhabited early formed rocks, and 3. younger than Archean-Protherozoic minerali microorganisms, that is later contamination. We made attempt to differentiate these 3 types of findings and tried to understand of burial of microorganisms. The structures belongs (from our point of view) to the first type, or real Archean, forms were under examination. Practical investigation of ancient microorganisms from Green-Stone-Belt of Northern Karelia turns to be very perspective. It shows that even in such ancient time as Archean ancient diverse world existed. Moreover probably such relatively highly organized cyanobacteria and perhaps eukaryotic formes existed in Archean world.

  17. Release of tensile strain on engineered human tendon tissue disturbs cell adhesions, changes matrix architecture, and induces an inflammatory phenotype

    DEFF Research Database (Denmark)

    Bayer, Monika L; Schjerling, Peter; Herchenhan, Andreas

    2014-01-01

    Mechanical loading of tendon cells results in an upregulation of mechanotransduction signaling pathways, cell-matrix adhesion and collagen synthesis, but whether unloading removes these responses is unclear. We investigated the response to tension release, with regard to matrix proteins, pro......-inflammatory mediators and tendon phenotypic specific molecules, in an in vitro model where tendon-like tissue was engineered from human tendon cells. Tissue sampling was performed 1, 2, 4 and 6 days after surgical de-tensioning of the tendon construct. When tensile stimulus was removed, integrin type collagen receptors...... were upregulated. Stimulation with the cytokine TGF-β1 had distinct effects on some tendon-related genes in both tensioned and de-tensioned tissue. These findings indicate an important role of mechanical loading for cellular and matrix responses in tendon, including that loss of tension leads...

  18. Biodegradable hyaluronic acid hydrogels to control release of dexamethasone through aqueous Diels-Alder chemistry for adipose tissue engineering.

    Science.gov (United States)

    Fan, Ming; Ma, Ye; Zhang, Ziwei; Mao, Jiahui; Tan, Huaping; Hu, Xiaohong

    2015-11-01

    A robust synthetic strategy of biopolymer-based hydrogels has been developed where hyaluronic acid derivatives reacted through aqueous Diels-Alder chemistry without the involvement of chemical catalysts, allowing for control and sustain release of dexamethasone. To conjugate the hydrogel, furan and maleimide functionalized hyaluronic acid were synthesized, respectively, as well as furan functionalized dexamethasone, for the covalent immobilization. Chemical structure, gelation time, morphologies, swelling kinetics, weight loss, compressive modulus and dexamethasone release of the hydrogel system in PBS at 37°C were studied. The results demonstrated that the aqueous Diels-Alder chemistry provides an extremely selective reaction and proceeds with high efficiency for hydrogel conjugation and covalent immobilization of dexamethasone. Cell culture results showed that the dexamethasone immobilized hydrogel was noncytotoxic and preserved proliferation of entrapped human adipose-derived stem cells. This synthetic approach uniquely allows for the direct fabrication of biologically functionalized gel scaffolds with ideal structures for adipose tissue engineering, which provides a competitive alternative to conventional conjugation techniques such as copper mediated click chemistry. Copyright © 2015. Published by Elsevier B.V.

  19. Bioplastics from microorganisms.

    Science.gov (United States)

    Luengo, José M; García, Belén; Sandoval, Angel; Naharro, Germán; Olivera, Elías R

    2003-06-01

    The term 'biomaterials' includes chemically unrelated products that are synthesised by microorganisms (or part of them) under different environmental conditions. One important family of biomaterials is bioplastics. These are polyesters that are widely distributed in nature and accumulate intracellularly in microorganisms in the form of storage granules, with physico-chemical properties resembling petrochemical plastics. These polymers are usually built from hydroxy-acyl-CoA derivatives via different metabolic pathways. Depending on their microbial origin, bioplastics differ in their monomer composition, macromolecular structure and physical properties. Most of them are biodegradable and biocompatible, which makes them extremely interesting from the biotechnological point of view.

  20. Physiologically anaerobic microorganisms of the deep subsurface

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, S.E. Jr.; Chung, K.T.

    1991-06-01

    This study seeks to determine numbers, diversity, and morphology of anaerobic microorganisms in 15 samples of subsurface material from the Idaho National Engineering Laboratory, in 18 samples from the Hanford Reservation and in 1 rock sample from the Nevada Test Site; set up long term experiments on the chemical activities of anaerobic microorganisms based on these same samples; work to improve methods for the micro-scale determination of in situ anaerobic microbial activity;and to begin to isolate anaerobes from these samples into axenic culture with identification of the axenic isolates.

  1. Motion of magnetotactic microorganisms

    International Nuclear Information System (INIS)

    Esquivel, D.M.S.; Barros, H.G. de P.L. de.

    1985-01-01

    Magnetic moments for different magnetotactic microorganisms are obtained by electron microscopy analyses and studies of motion by optical microscopy. The results are analysed in terms of a model due to C.Bean. The considerations presented suggest that magnetotaxy is an efficient mechanism for orientation only if the time for reorientation is smaller than the cycles of environmental perturbations. (Author) [pt

  2. Effectiveness of the two microorganisms Lactobacillus fermentum LF15 and Lactobacillus plantarum LP01, formulated in slow-release vaginal tablets, in women affected by bacterial vaginosis: a pilot study.

    Science.gov (United States)

    Vicariotto, Franco; Mogna, Luca; Del Piano, Mario

    2014-01-01

    Bacterial vaginosis (BV) is the most common reason for abnormal vaginal discharge in reproductive-age women and one of its most important causative agents is the gram-variable bacterium Gardnerella vaginalis. BV is not accompanied by significant local inflammation, whereas the "fishy odor" test is always positive. In contrast, aerobic vaginitis (AV) is predominantly associated with Escherichia coli, but Streptococcus agalactiae and Staphylococcus aureus are also involved. Standard treatment of BV consists of oral or intravaginal antibiotics, although these are unable to spontaneously restore normal flora characterized by a high concentration of lactobacilli. The main limitation is the inability to offer a long-term defensive barrier, thus facilitating relapses and recurrences. This study was undertaken firstly to assess the ability of selected lactobacilli to in vitro antagonize G. vaginalis to determine an association with a strain able to inhibit E. coli, thus identifying a possible use in AV. The second step of the study was to conduct a human pilot trial in women affected by BV using an association of the most promising and active bacteria. For this purpose, neutralized supernatants of individual lactobacilli were tested at percentages ranging from 0.5% to 4% to determine their ability to hinder the growth of G. vaginalis American Type Culture Collection 10231. The bacterium that was able to exert the strongest inhibition was subsequently tested with Lactobacillus plantarum LP01 in a human intervention, placebo-controlled, pilot trial involving 34 female subjects (aged between 18 and 50, mean 34.7±8.9, no menopausal women) diagnosed with BV. The 2 microorganisms Lactobacillus fermentum LF15 (DSM 26955) and L. plantarum LP01 (LMG P-21021) were delivered to the vagina by means of slow-release vaginal tablets, also containing 50 mg of tara gum. The amount of each strain was 400 million live cells per dose. The women were instructed to apply a vaginal tablet once

  3. Inactivation of Microorganisms

    Science.gov (United States)

    Alzamora, Stella Maris; Guerrero, Sandra N.; Schenk, Marcela; Raffellini, Silvia; López-Malo, Aurelio

    Minimal processing techniques for food preservation allow better retention of product flavor, texture, color, and nutrient content than comparable conventional treatments. A wide range of novel alternative physical factors have been intensely investigated in the last two decades. These physical factors can cause inactivation of microorganisms at ambient or sublethal temperatures (e.g., high hydrostatic pressure, pulsed electric fields, ultrasound, pulsed light, and ultraviolet light). These technologies have been reported to reduce microorganism population in foods while avoiding the deleterious effects of severe heating on quality. Among technologies, high-energy ultrasound (i.e., intensities higher than 1 W/cm2, frequencies between 18 and 100 kHz) has attracted considerable interest for food preservation applications (Mason et al., 1996; Povey and Mason, 1998).

  4. Properties of thermophilic microorganisms

    International Nuclear Information System (INIS)

    Ljungdahl, L.G.

    1984-01-01

    Microorganisms are called thermophilic or extreme thermophilic (caldo-active) if they grow and reproduce over 47 0 C and 70 0 C, respectively. A survey of growth characteristics of thermophiles is presented and it includes those which also live at extreme pH. The prevalent but not completely emcompassing theory of the ability of thermophiles to grow at high temperatures is that they have macromolecules and cell organelles with high thermostability. Work on some proteins and cell organelles from thermophiles is reviewed. The thermostabilities of these components are compared with those of the living cells, and factors which may govern optimum as well as minimum growth temperatures of microorganisms are discussed. Examples are from the literature but also include enzymes involved in tetrahydrofolate metabolism and other proteins of acetogenic therhmophilic bacteria which are presently studied in the author's laboratory

  5. Metal-microorganism interactions

    International Nuclear Information System (INIS)

    Andres, Y.; Thouand, G.; Redercher, S.; Boualam, M.; Texier, A.Cl.; Hoeffer, R.

    1997-01-01

    The physico-chemical procedures of treating the metalliferous effluents are not always adapted to de polluting the slightly concentrated industrial wastes. An alternative idea was advanced, implying the ability of some microorganisms to fix in considerable amounts the metal ions present in aqueous solutions, possibly in a selective way. This approach has been investigated thoroughly during the last 30 years, particularly from a mechanistic point of view. The advantage of the microorganisms lies mainly in the large diversity of bacteria and in their chemical state dependent interaction with metals, as well as, in the possibilities of developing their selective and quantitative separation properties. A biomass from Mycobacterium smegmatis, an acidic alcoholic resistant bacteria, has been used to prepare a bio-sorption support allowing the preferential sorption of thorium as compared to uranium and lanthanum. These studies have been extended to biological polymers such as chitosan and to studies related to bioaccumulation mechanisms and/or to the microbial resistances towards metals

  6. Microorganisms of Grape Berries

    Directory of Open Access Journals (Sweden)

    Kántor Attila

    2017-12-01

    Full Text Available Grape surface is an unstable habitat that changes greatly according to the stage of grape ripening. Different bacteria and yeasts can colonise the surface of grape berry and the diversity of microorganisms depends on the stage of ripening, pesticide application and health condition. The aim of this study was to study the microflora of the surface of grape berries. Altogether, 19 grape samples from Slovakia were collected. The spread plate method was applied and a 100 μL inoculum of each dilution (10−2, 10−3 was plated on TSA, MEA, and MRS agar for isolation of microorganisms from grapes. Proteins were extracted from cells by ethanol/formic acid extraction procedure. MALDI-TOF Mass Spectrometry was used for identification of microorganisms. In total, 11 genera of Gram-negative bacteria, 11 of Gram-positive bacteria and nine of yeasts were identified. Among 200 isolates, Gram-negative, Gram-positive bacteria and yeasts represented 11%, 27% and 62% of the total number of isolates studied. The most common genera of isolated yeasts were Hanseniaspora (37%, Metschnikowia (31%, and Rhodotorula (10%. The most frequently isolated among Gram-negative bacteria were Acinetobacter (22%, Pseudomonas (22% and Sphingomonas (13%. The most common genera of Gram-positive bacteria were Bacillus (20%, Lactobacillus (19%, Leuconostoc and Staphylococcus (11%, respectively.

  7. The environmental impact of mine wastes - roles of microorganisms and their significance in treatment of mine wastes

    International Nuclear Information System (INIS)

    Ledin, M.; Pedersen, K.

    1996-01-01

    Mine wastes constitute a potential source of contamination to the environment, as heavy metals and acid are released in large amounts. A great variety of microorganisms has been found in mine wastes and microbiological processes are usually responsible for the environmental hazard created by mine wastes. However, microorganisms can also be used to retard the adverse impact of mine wastes on the environment. Conventionally, the mine drainage as well as the waste itself can be treated with alkali to increase pH and precipitate metals. The main drawback of this method is that it has to be continuously repeated to be fully effective. There may also be negative effects on beneficial microorganisms. Several other treatment methods have been developed to stop weathering processes thereby reducing the environmental impact of mine wastes. The other main approach is to treat the drainage water. Various methods aim at using microorganisms for this in natural or engineered systems. Recently, much interest has been focused on the use of natural or artificial wetlands for treatment. In general, the activity of microorganisms is neglected in the design of mine waste treatment systems, and the treatments are created merely from a technical point of view. This can result in situations where unexpected microbial processes take over, and, in the worst scenario, the overall effect is opposite to the desired

  8. The Effect of Ethanol Addition to Gasoline on Low- and Intermediate-Temperature Heat Release under Boosted Conditions in Kinetically Controlled Engines

    Science.gov (United States)

    Vuilleumier, David Malcolm

    The detailed study of chemical kinetics in engines has become required to further advance engine efficiency while simultaneously lowering engine emissions. This push for higher efficiency engines is not caused by a lack of oil, but by efforts to reduce anthropogenic carbon dioxide emissions, that cause global warming. To operate in more efficient manners while reducing traditional pollutant emissions, modern internal combustion piston engines are forced to operate in regimes in which combustion is no longer fully transport limited, and instead is at least partially governed by chemical kinetics of combusting mixtures. Kinetically-controlled combustion allows the operation of piston engines at high compression ratios, with partially-premixed dilute charges; these operating conditions simultaneously provide high thermodynamic efficiency and low pollutant formation. The investigations presented in this dissertation study the effect of ethanol addition on the low-temperature chemistry of gasoline type fuels in engines. These investigations are carried out both in a simplified, fundamental engine experiment, named Homogeneous Charge Compression Ignition, as well as in more applied engine systems, named Gasoline Compression Ignition engines and Partial Fuel Stratification engines. These experimental investigations, and the accompanying modeling work, show that ethanol is an effective scavenger of radicals at low temperatures, and this inhibits the low temperature pathways of gasoline oxidation. Further, the investigations measure the sensitivity of gasoline auto-ignition to system pressure at conditions that are relevant to modern engines. It is shown that at pressures above 40 bar and temperatures below 850 Kelvin, gasoline begins to exhibit Low-Temperature Heat Release. However, the addition of 20% ethanol raises the pressure requirement to 60 bar, while the temperature requirement remains unchanged. These findings have major implications for a range of modern engines

  9. Atmospheric Sampling of Microorganisms with UAS

    Science.gov (United States)

    Schmale, D. G., III

    2017-12-01

    Many microorganisms relevant to crops, domestic animals, and humans are transported over long distances through the atmosphere. Some of these atmospheric microbes catalyze the freezing of water at higher temperatures and facilitate the onset of precipitation. A few have crossed continents. New technologies are needed to study the movement of microorganisms in the atmosphere. We have used unmanned aircraft systems (UAS) to study the transport of microorganisms tens to hundreds of meters above the ground. These UAS are equipped with unique devices for collecting microbes in the atmosphere during flight. Autonomous systems enable teams of UAS to perform complex atmospheric sampling tasks, and coordinate flight missions with one another. Data collected with UAS can be used to validate and improve disease forecasting models along highways in the sky, connecting transport scales across farms, states, and continents. Though terrestrial environments are often considered a major contributor to atmospheric microbial aerosols, little is known about aquatic sources of microbial aerosols. Droplets containing microorganisms can aerosolize from the water surface, liberating them into the atmosphere. We are using teams of unmanned surface vehicles (USVs) and UAS to study the aerosolization of microbes from aquatic environments. Controlled flume studies using highspeed video have allowed us to observe unique aerosolization phenomena that can launch microbes out of the water and into the air. Unmanned systems may be used to excite the next generation of biologists and engineers, and raise important ethical considerations about the future of human-robot interactions.

  10. Artifical Microorganism Infection in Aviation Kerosene

    Directory of Open Access Journals (Sweden)

    Dušan Vallo

    2004-12-01

    Full Text Available The fuel used in the aviation engineering has to be clean and dry, it may not contain mechanical impurities and water. Water inaviation kerosene may occur in soluble and insoluble form. The danger inheres in the insoluble form, which may drop out in the crystallineform and cause various failures, such as those caused by mechanical impurities. The water assists in the biological matter formation createdby various species of microorganisms (bacteria, mould fungi and yeast. The microorganisms, present in water phase occurring on thebottom of tanks or on the interface water phase – kerosene, grow and reproduce and subsequently may pollute (impair the fuel by thebiomass or by the products of their metabolism. There is a possibility to infect the fuel artificially by a selected reference microorganismstrain, which usually occur in contaminated fuel, or by microorganisms which cause a biological contamination of aviation kerosene.Out of the selected reference strains used in the experiments, the reference strains of Proteus vulgaris, Sacharamyces cerevisiae andClostridium perfringens were not cultivated in the sterile aviation kerosene and the propagating nutrient medium. The aviation kerosene actsas a biocide medium for the presented reference microorganism strains.

  11. Modeling of release of radionuclides from an engineered disposal facility for shallow-land disposal of low-level radioactive wastes

    International Nuclear Information System (INIS)

    Matsuzuru, H.; Suzuki, A.

    1989-01-01

    The computer code, ENBAR-1, for the simulation of radionuclide releases from an engineered disposal facility has been developed to evaluate the source term for subsequent migration of radionuclides in and through a natural barrier. The system considered here is that a waste package (waste form and container) is placed, together with backfill materials, into a concrete pit as a disposal unit for shallow-land disposal of low-level radioactive wastes. The code developed includes the following modules: water penetration into a concrete pit, corrosion of a drum as a container, leaching of radionuclides from a waste form, migration of radionuclides in backfill materials, release of radionuclides from the pit. The code has the advantage of its simplicity of operation and presentation while still allowing comprehensive evaluation of each element of an engineered disposal facility to be treated. The performance and source term of the facility might be readily estimated with a few key parameters to define the problem

  12. Genetic programming in microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Hopwood, D A

    1981-11-01

    Formerly, when microbiologists had only existing organisms at their disposal whose characteristics could only be changed randomly by genetic experiments, they used to dream of programmed genetic changes. This dream has come true with modern genetic engineering.

  13. New micro-organism

    Energy Technology Data Exchange (ETDEWEB)

    Takakuwa, Masayoshi; Hashimoto, Gotaro

    1987-09-12

    Invention relates with a new organism for the coal liquefying desulfurization. This micro-organism conducts a good sporulation on a culture medium which contains a coal as an only carbon source. It belongs to Penicillium and named Penicillium MT-6001 registered at Fermentation Research Institute No. 8463. Coal powder is thrown into a reaction vessel which accommodated a culture solution of this bacteria, and the surface of the solution is covered with liquid paraffin; coal powder is treated of liquefaction for about 5 hours while maintaining the anaerobic condition and slowly agitating to form a transparent solution layer on the surface of the reactor together with liquid paraffin. Liquefied product shows an analysis pattern similar to naphthenic petroleum containing a lipid with polar radical. (2 figs)

  14. Proteolysis in hyperthermophilic microorganisms

    Directory of Open Access Journals (Sweden)

    Donald E. Ward

    2002-01-01

    Full Text Available Proteases are found in every cell, where they recognize and break down unneeded or abnormal polypeptides or peptide-based nutrients within or outside the cell. Genome sequence data can be used to compare proteolytic enzyme inventories of different organisms as they relate to physiological needs for protein modification and hydrolysis. In this review, we exploit genome sequence data to compare hyperthermophilic microorganisms from the euryarchaeotal genus Pyrococcus, the crenarchaeote Sulfolobus solfataricus, and the bacterium Thermotoga maritima. An overview of the proteases in these organisms is given based on those proteases that have been characterized and on putative proteases that have been identified from genomic sequences, but have yet to be characterized. The analysis revealed both similarities and differences in the mechanisms utilized for proteolysis by each of these hyperthermophiles and indicated how these mechanisms relate to proteolysis in less thermophilic cells and organisms.

  15. Radioresistant microorganisms and food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ito, H [Japan Atomic Energy Research Inst., Takasaki, Gunma. Takasaki Radiation Chemistry Research Establishment

    1976-01-01

    This paper deals with Micrococcus radiodurans, Arthrobacter radiotolerance, etc., which were isolated and discovered as radioresistant microorganisms. As for the explanation of the mechanism of radioresistance of these microorganisms, the consideration that these organisms have marked repair power of the damaged DNA and have many opportunity to repair the damaged DNA because of their long fission term were cited. The relationship between the radioresistance of microorganisms and food irradiation was also mentioned.

  16. [Genome editing of industrial microorganism].

    Science.gov (United States)

    Zhu, Linjiang; Li, Qi

    2015-03-01

    Genome editing is defined as highly-effective and precise modification of cellular genome in a large scale. In recent years, such genome-editing methods have been rapidly developed in the field of industrial strain improvement. The quickly-updating methods thoroughly change the old mode of inefficient genetic modification, which is "one modification, one selection marker, and one target site". Highly-effective modification mode in genome editing have been developed including simultaneous modification of multiplex genes, highly-effective insertion, replacement, and deletion of target genes in the genome scale, cut-paste of a large DNA fragment. These new tools for microbial genome editing will certainly be applied widely, and increase the efficiency of industrial strain improvement, and promote the revolution of traditional fermentation industry and rapid development of novel industrial biotechnology like production of biofuel and biomaterial. The technological principle of these genome-editing methods and their applications were summarized in this review, which can benefit engineering and construction of industrial microorganism.

  17. The impact of the accuracy of indicator diagrams on the heat release characteristics calculation, used in the diagnosis of marine diesel engine

    Directory of Open Access Journals (Sweden)

    Witkowski Kazimierz

    2017-01-01

    Full Text Available The paper analyzes the possibility to use the electronic type indicators in the diagnosis of marine engines. It has been shown that in-depth analysis of indicator diagrams would be useful – calculation of heat release characteristics. To make this possible, measuring indicated systems should meet a number of important requirements in or-der to ensure that they can be used for the diagnostic purposes. These includes: high precision sensors for the measurement of cylinder pressure, high speed and accuracy of measuring and recording of measured values. These also includes reliable determination of the top dead center piston (TDC. In order to demonstrate the impact of positional error TDC, simulation study was conducted in which indicated diagrams were used, obtained on a medium-speed four-stroke marine diesel engine type A25/30 and the low-speed two-stroke marine diesel engine type RTA76, Sulzer company.

  18. COMBUSTION HEAT RELEASE RATE ANALYSIS OF C.I. ENGINE WITH SECONDARY CO-INJECTION OF DEE-H2O SOLUTION - A VIBRATIONAL APPROACH

    Directory of Open Access Journals (Sweden)

    Y. V. V. SATYANARAYANA MURTHY

    2015-08-01

    Full Text Available This paper discusses the combustion propensity of single cylinder direct injection engine fueled with palm kernel methyl ester (PKME, which is non- edible oil and a secondary co-injection of saturated Diethyl ether (DEE with water. DEE along with water is fumigated through a high pressure nozzle fitted to the inlet manifold of the engine and the flow rate of the secondary injection was electronically controlled. DEE is known to improve the cold starting problem in engines when used in straight diesel fuel. However, its application in emulsion form is little known. Experimental results show that for 5% DEE- H2O solution injection, occurrence of maximum net heat release rate is delayed due to controlled premixed combustion, which normally helped in better torque conversion when the piston is in accelerated mode. Vibration measurements in the frequency range of 900Hz to 1300Hz revealed that a new mode of combustion has taken place with different excitation frequencies.

  19. Authorized Limits for the Release of a 25 Ton Locomotive, Serial Number 21547, at the Area 25 Engine Maintenance, Assembly, and Disassembly Facility, Nevada Test Site, Nevada

    International Nuclear Information System (INIS)

    Gwin, Jeremy; Frenette, Douglas

    2010-01-01

    This document contains process knowledge and radiological data and analysis to support approval for release of the 25-ton locomotive, Serial Number 21547, at the Area 25 Engine Maintenance, Assembly, and Disassembly (EMAD) Facility, located on the Nevada Test Site (NTS). The 25-ton locomotive is a small, one-of-a-kind locomotive used to move railcars in support of the Nuclear Engine for Rocket Vehicle Application project. This locomotive was identified as having significant historical value by the Nevada State Railroad Museum in Boulder City, Nevada, where it will be used as a display piece. A substantial effort to characterize the radiological conditions of the locomotive was undertaken by the NTS Management and Operations Contractor, National Security Technologies, LLC (NSTec). During this characterization process, seven small areas on the locomotive had contamination levels that exceeded the NTS release criteria (limits consistent with U.S. Department of Energy (DOE) Order DOE O 5400.5, 'Radiation Protection of the Public and the Environment'). The decision was made to perform radiological decontamination of these known accessible impacted areas to further the release process. On February 9, 2010, NSTec personnel completed decontamination of these seven areas to within the NTS release criteria. Although all accessible areas of the locomotive had been successfully decontaminated to within NTS release criteria, it was plausible that inaccessible areas of the locomotive (i.e., those areas on the locomotive where it was not possible to perform radiological surveys) could potentially have contamination above unrestricted release limits. To access the majority of these inaccessible areas, the locomotive would have to be disassembled. A complete disassembly for a full radiological survey could have permanently destroyed parts and would have ruined the historical value of the locomotive. Complete disassembly would also add an unreasonable financial burden for the

  20. The fast release of stem cells from alginate-fibrin microbeads in injectable scaffolds for bone tissue engineering

    Science.gov (United States)

    Zhou, Hongzhi; Xu, Hockin H. K.

    2011-01-01

    Stem cell-encapsulating hydrogel microbeads of several hundred microns in size suitable for injection, that could quickly degrade to release the cells, are currently unavailable. The objectives of this study were to: (1) develop oxidized alginate-fibrin microbeads encapsulating human umbilical cord mesenchymal stem cells (hUCMSCs); (2) investigate microbead degradation, cell release, and osteogenic differentiation of the released cells for the first time. Three types of microbeads were fabricated to encapsulate hUCMSCs: (1) Alginate microbeads; (2) oxidized alginate microbeads; (3) oxidized alginate-fibrin microbeads. Microbeads with sizes of about 100–500 µm were fabricated with 1×106 hUCMSCs/mL of alginate. For the alginate group, there was little microbead degradation, with very few cells released at 21 d. For oxidized alginate, the microbeads started to slightly degrade at 14 d. In contrast, the oxidized alginate-fibrin microbeads started to degrade at 4 d and released the cells. At 7 d, the number of released cells greatly increased and showed a healthy polygonal morphology. At 21 d, the oxidized alginate-fibrin group had a live cell density that was 4-fold that of the oxidized alginate group, and 15-fold that of the alginate group. The released cells had osteodifferentiation, exhibiting highly elevated bone marker gene expressions of ALP, OC, collagen I, and Runx2. Alizarin staining confirmed the synthesis of bone minerals by hUCMSCs, with the mineral concentration at 21 d being 10-fold that at 7 d. In conclusion, fast-degradable alginate-fibrin microbeads with hUCMSC encapsulation were developed that could start to degrade and release the cells at 4 d. The released hUCMSCs had excellent proliferation, osteodifferentiation, and bone mineral synthesis. The alginate-fibrin microbeads are promising to deliver stem cells inside injectable scaffolds to promote tissue regeneration. PMID:21757229

  1. Polysaccharides from Extremophilic Microorganisms

    Science.gov (United States)

    Nicolaus, B.; Moriello, V. Schiano; Lama, L.; Poli, A.; Gambacorta, A.

    2004-02-01

    Several marine thermophilic strains were analyzed for exopolysaccharide production. The screening process revealed that a significant number of thermophilic microorganisms were able to produce biopolymers, and some of them also revealed interesting chemical compositions. We have identified four new polysaccharides from thermophilic marine bacteria, with complex primary structures and with different repetitive units: a galacto-mannane type from strain number 4004 and mannane type for the other strains. The thermophilic Bacillus thermantarcticus produces two exocellular polysaccharides (EPS 1, EPS 2) that give the colonies a typical mucous character. The exopolysaccharide fraction was produced with all substrates assayed, although a higher yield 400 mg liter-1 was obtained with mannose as carbon and energy source. NMR spectra confirmed that EPS 1 was a heteropolysaccharide of which the repeating unit was constituted by four different α-D-mannoses and three different β-D-glucoses. It seems to be close to some xantan polymers. EPS 2 was a mannan. Four different α-D-mannoses were found as the repeating unit. Production and chemical studies of biopolymers produced by halophilic archaea, Haloarcula species were also reported.

  2. A field release of genetically engineered gypsy moth (Lymantria dispar L.) Nuclear Polyhedrosis Virus (LdNPV)

    Science.gov (United States)

    Vincent D' Amico; Joseph S. Elkinton; John D. Podgwaite; James M. Slavicek; Michael L. McManus; John P. Burand

    1999-01-01

    The gypsy moth (Lymantria dispar L.) nuclear polyhedrosis virus was genetically engineered for nonpersistence by removal of the gene coding for polyhedrin production and stabilized using a coocclusion process. A β-galactosidase marker gene was inserted into the genetically engineered virus (LdGEV) so that infected larvae could be tested for...

  3. Radiological effluents released from nuclear rocket and ramjet engine tests at the Nevada Test Site 1959 through 1969: Fact Book

    Energy Technology Data Exchange (ETDEWEB)

    Friesen, H.N.

    1995-06-01

    Nuclear rocket and ramjet engine tests were conducted on the Nevada Test Site (NTS) in Area 25 and Area 26, about 80 miles northwest of Las Vegas, Nevada, from July 1959 through September 1969. This document presents a brief history of the nuclear rocket engine tests, information on the off-site radiological monitoring, and descriptions of the tests.

  4. Modeling of heat release and emissions from droplet combustion of multi component fuels in compression ignition engines

    DEFF Research Database (Denmark)

    Ivarsson, Anders

    emissions from the compression ignition engines (CI engines or diesel engines) are continuously increased. To comply with this, better modeling tools for the diesel combustion process are desired from the engine developers. The complex combustion process of a compression ignition engine may be divided...... it is well suited for optical line of sight diagnostics in both pre and post combustion regions. The work also includes some preliminary studies of radiant emissions from helium stabilized ethylene/air and methane/oxygen flames. It is demonstrated that nano particles below the sooting threshold actually...... of ethylene/air flames well known from the experimental work, was used for the model validation. Two cases were helium stabilized flames with φ = 1 and 2.14. The third case was an unstable flame with φ = 2.14. The unstable case was used to test whether a transient model would be able to predict the frequency...

  5. Environmental pH-controlled loading and release of protein on mesoporous hydroxyapatite nanoparticles for bone tissue engineering.

    Science.gov (United States)

    Zhang, Ning; Gao, Tianlin; Wang, Yu; Wang, Zongliang; Zhang, Peibiao; Liu, Jianguo

    2015-01-01

    To explore the controlled delivery of protein drugs in micro-environment established by osteoblasts or osteoclasts, the loading/release properties of bovine serum albumin (BSA) depending on pH environment were assessed. The adsorption amounts over mesoporous hydroxyapatite (MHA) or hydroxyapatite (HA) decreased as the pH increased, negatively correlating with zeta-potential values. The adsorption behavior over MHA fits well with the Freundlich and Langmuir models at different pHs. The results suggest that the adsorbed amount of protein on MHA or HA depended on the pH of protein solution. MHA adsorbed BSA at basic pH (MHApH 8.4) exhibited a different release kinetics compared with those in acid and neutral environments (MHApH 4.7 and MHApH 7.4), indicating that the release of protein could be regulated by environmental pH at which MHAs adsorb protein. MHApH 8.4 showed a sustained release for 6h before a gradual release when immersing in acidic environment, which is 2h longer than that in neutral environment. This suggests that MHApH 8.4 showed a more sustained release in acidic environment, which can be established by osteoclasts. The variation of adsorption strength between protein and MHA may be responsible for these behaviors. Our findings may be very useful for the development of MHA applications on both bone repair and protein delivery. Copyright © 2014. Published by Elsevier B.V.

  6. Influence of environmental parameters and of their interactions on the release of metal(loid)s from a construction material in hydraulic engineering.

    Science.gov (United States)

    Schmukat, A; Duester, L; Goryunova, E; Ecker, D; Heininger, P; Ternes, T A

    2016-03-05

    Besides the leaching behaviour of a construction material under standardised test-specific conditions with laboratory water, for some construction materials it is advisable to test their environmental behaviour also under close to end use conditions. The envisaged end use combined with the product characteristics (e.g. mineral phases) is decisive for the choice of environmental factors that may change the release of substance that potentially cause adverse environmental effects (e.g. fertilisation or ecotoxicity). At the moment an experimental link is missing between mono-factorial standardised test systems and non standardised complex incubation experiments such as mesocosms which are closer to environmental conditions. Multi-factorial batch experiments may have the potential to close the gap. To verify this, batch experiments with copper slag were performed which is used as armour stones in hydraulic engineering. Design of experiments (DoE) was applied to evaluate the impact of pH, ionic strength, temperature and sediment content on the release of As, Cu, Mo, Ni, Pb, Sb and Zn. The study shows that release and sediment-eluent partitioning of metal(loid)s are impacted by interactions between the studied factors. Under the prevalent test conditions sediment acts as a sink enhancing most strongly the release of elements from the material. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Idaho National Engineering Laboratory response to the December 13, 1991, Congressional inquiry on offsite release of hazardous and solid waste containing radioactive materials from Department of Energy facilities

    International Nuclear Information System (INIS)

    Shapiro, C.; Garcia, K.M.; McMurtrey, C.D.; Williams, K.L.; Jordan, P.J.

    1992-05-01

    This report is a response to the December 13, 1991, Congressional inquiry that requested information on all hazardous and solid waste containing radioactive materials sent from Department of Energy facilities to offsite facilities for treatment or disposal since January 1, 1981. This response is for the Idaho National Engineering Laboratory. Other Department of Energy laboratories are preparing responses for their respective operations. The request includes ten questions, which the report divides into three parts, each responding to a related group of questions. Part 1 answers Questions 5, 6, and 7, which call for a description of Department of Energy and contractor documentation governing the release of waste containing radioactive materials to offsite facilities. ''Offsite'' is defined as non-Department of Energy and non-Department of Defense facilities, such as commercial facilities. Also requested is a description of the review process for relevant release criteria and a list of afl Department of Energy and contractor documents concerning release criteria as of January 1, 1981. Part 2 answers Questions 4, 8, and 9, which call for information about actual releases of waste containing radioactive materials to offsite facilities from 1981 to the present, including radiation levels and pertinent documentation. Part 3 answers Question 10, which requests a description of the process for selecting offsite facilities for treatment or disposal of waste from Department of Energy facilities. In accordance with instructions from the Department of Energy, the report does not address Questions 1, 2, and 3

  8. On the experimental approaches for the assessment of the release of engineered nanomaterials from nanocomposites by physical degradation processes

    International Nuclear Information System (INIS)

    Blázquez, M; Unzueta, I; Egizabal, A

    2014-01-01

    The LIFE+ Project SIRENA, Simulation of the release of nanomaterials from consumer products for environmental exposure assessment, (LIFE11 ENV/ES/596) has set up a Technological Surveillance System (TSS) to trace technical references at worldwide level related to nanocomposites and the release from nanocomposites. So far a total of seventy three items of different nature (from peer reviewed articles to presentations and contributions to congresses) have been selected and classified as n anomaterials release simulation technologies . In present document, different approaches for the simulation of different life cycle stages through the physical degradation of polymer nanocomposites at laboratory scale are assessed. In absence of a reference methodology, the comparison of the different protocols used still remains a challenge

  9. On the experimental approaches for the assessment of the release of engineered nanomaterials from nanocomposites by physical degradation processes

    Science.gov (United States)

    Blázquez, M.; Egizabal, A.; Unzueta, I.

    2014-08-01

    The LIFE+ Project SIRENA, Simulation of the release of nanomaterials from consumer products for environmental exposure assessment, (LIFE11 ENV/ES/596) has set up a Technological Surveillance System (TSS) to trace technical references at worldwide level related to nanocomposites and the release from nanocomposites. So far a total of seventy three items of different nature (from peer reviewed articles to presentations and contributions to congresses) have been selected and classified as "nanomaterials release simulation technologies". In present document, different approaches for the simulation of different life cycle stages through the physical degradation of polymer nanocomposites at laboratory scale are assessed. In absence of a reference methodology, the comparison of the different protocols used still remains a challenge.

  10. The application of powerful promoters to enhance gene expression in industrial microorganisms.

    Science.gov (United States)

    Zhou, Shenghu; Du, Guocheng; Kang, Zhen; Li, Jianghua; Chen, Jian; Li, Huazhong; Zhou, Jingwen

    2017-02-01

    Production of useful chemicals by industrial microorganisms has been attracting more and more attention. Microorganisms screened from their natural environment usually suffer from low productivity, low stress resistance, and accumulation of by-products. In order to overcome these disadvantages, rational engineering of microorganisms to achieve specific industrial goals has become routine. Rapid development of metabolic engineering and synthetic biology strategies provide novel methods to improve the performance of industrial microorganisms. Rational regulation of gene expression by specific promoters is essential to engineer industrial microorganisms for high-efficiency production of target chemicals. Identification, modification, and application of suitable promoters could provide powerful switches at the transcriptional level for fine-tuning of a single gene or a group of genes, which are essential for the reconstruction of pathways. In this review, the characteristics of promoters from eukaryotic, prokaryotic, and archaea microorganisms are briefly introduced. Identification of promoters based on both traditional biochemical and systems biology routes are summarized. Besides rational modification, de novo design of promoters to achieve gradient, dynamic, and logic gate regulation are also introduced. Furthermore, flexible application of static and dynamic promoters for the rational engineering of industrial microorganisms is highlighted. From the perspective of powerful promoters in industrial microorganisms, this review will provide an extensive description of how to regulate gene expression in industrial microorganisms to achieve more useful goals.

  11. Addition of waste and introduction of microorganisms after 45 years of soil degradation

    Directory of Open Access Journals (Sweden)

    Adriana Avelino Santos

    Full Text Available ABSTRACT The construction of hydroelectric power plants (HPP may result in environmental problems, such as extensive areas of exposed subsoil and conditions of extreme degradation. These areas require alternative that minimize impact and allow partial recovery of their ecosystem functions and vegetation. This study aimed to evaluate the effects of residue addition (organic/macrophytes - OR and inorganic/ash - AR, hydrogel, and inoculation of microorganisms in degraded soil, cultivated with Jatropha curcas, through fertility and microbial activity. A conserved Cerrado ("savannah" soil was the source of microorganisms - mainly mycorrhizal fungi. The experiment was conducted for 12 months (during 2010/2011 at the farm of UNESP-School of Engineering/Campus of Ilha Solteira, Selvíria-MS, Brazil, installed in an area where the soil was degraded during the HPP construction, in the 1960s. The experimental design was complete randomized blocks, using a 2×2×4 factorial scheme, i.e., two inoculation treatments (with and without, two hydrogel treatments (with and without, and four residue treatments to introduce the J. curcas (OR, AR, OR + AR, and control without residues, with four replicates and five plants evaluated per replicate. The soil fertility analyses, quantification of microbial biomass carbon (MBC, and released C as CO2 (CO2-C, microbial quotient (qMic, and metabolic quotient (qCO2 were carried out 12 months after planting. The fertility positively responded to the addition of OR and OR + AR, with an increase in pH and SB and reduction in Al and H + Al. The inoculation of soil microorganisms associated with OR and OR + AR residue treatments raised the released CO2-C, MBC, and qMic. The addition of hydrogel combined with OR treatment contributed to the increase in the values of MBC and qMic.

  12. Pathways and mechanisms for product release in the engineered haloalkane dehalogenases explored using classical and random acceleration molecular dynamics simulations

    Czech Academy of Sciences Publication Activity Database

    Klvana, M.; Pavlová, M.; Koudeláková, T.; Chaloupková, R.; Dvořák, P.; Prokop, Z.; Stsiapanava, A.; Kutý, Michal; Kutá-Smatanová, Ivana; Dohnálek, Jan; Kulhánek, P.; Damborský, J.

    2009-01-01

    Roč. 392, č. 5 (2009), s. 1339-1356 ISSN 0022-2836 R&D Projects: GA MŠk(CZ) LC06010 Institutional research plan: CEZ:AV0Z40500505; CEZ:AV0Z60870520 Keywords : haloalkane dehalogenase * product release * random acceleration molecular dynamics Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.871, year: 2009

  13. Synthetic biology expands chemical control of microorganisms.

    Science.gov (United States)

    Ford, Tyler J; Silver, Pamela A

    2015-10-01

    The tools of synthetic biology allow researchers to change the ways engineered organisms respond to chemical stimuli. Decades of basic biology research and new efforts in computational protein and RNA design have led to the development of small molecule sensors that can be used to alter organism function. These new functions leap beyond the natural propensities of the engineered organisms. They can range from simple fluorescence or growth reporting to pathogen killing, and can involve metabolic coordination among multiple cells or organisms. Herein, we discuss how synthetic biology alters microorganisms' responses to chemical stimuli resulting in the development of microbes as toxicity sensors, disease treatments, and chemical factories. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Inventory of Engineered Nanoparticle-Containing Consumer Products Available in the Singapore Retail Market and Likelihood of Release into the Aquatic Environment.

    Science.gov (United States)

    Zhang, Yuanyuan; Leu, Yu-Rui; Aitken, Robert J; Riediker, Michael

    2015-07-24

    Consumer products containing engineered nanoparticles (ENP) are already entering the marketplace. This leads, inter alia, to questions about the potential for release of ENP into the environment from commercial products. We have inventoried the prevalence of ENP-containing consumer products in the Singapore market by carrying out onsite assessments of products sold in all major chains of retail and cosmetic stores. We have assessed their usage patterns and estimated release factors and emission quantities to obtain a better understanding of the quantities of ENP that are released into which compartments of the aquatic environment in Singapore. Products investigated were assessed for their likelihood to contain ENP based on the declaration of ENP by producers, feature descriptions, and the information on particle size from the literature. Among the 1,432 products investigated, 138 were "confirmed" and 293 were "likely" to contain ENP. Product categories included sunscreens, cosmetics, health and fitness, automotive, food, home and garden, clothing and footwear, and eyeglass/lens coatings. Among the 27 different types of nanomaterials identified, SiO2 was predominant, followed by TiO2 and ZnO, Carbon Black, Ag, and Au. The amounts of ENP released into the aquatic system, which was estimated on the basis of typical product use, ENP concentration in the product, daily use quantity, release factor, and market share, were in the range of several hundred tons per year. As these quantities are likely to increase, it will be important to further study the fate of ENP that reach the aquatic environment in Singapore.

  15. Inventory of Engineered Nanoparticle-Containing Consumer Products Available in the Singapore Retail Market and Likelihood of Release into the Aquatic Environment

    Directory of Open Access Journals (Sweden)

    Yuanyuan Zhang

    2015-07-01

    Full Text Available Consumer products containing engineered nanoparticles (ENP are already entering the marketplace. This leads, inter alia, to questions about the potential for release of ENP into the environment from commercial products. We have inventoried the prevalence of ENP-containing consumer products in the Singapore market by carrying out onsite assessments of products sold in all major chains of retail and cosmetic stores. We have assessed their usage patterns and estimated release factors and emission quantities to obtain a better understanding of the quantities of ENP that are released into which compartments of the aquatic environment in Singapore. Products investigated were assessed for their likelihood to contain ENP based on the declaration of ENP by producers, feature descriptions, and the information on particle size from the literature. Among the 1,432 products investigated, 138 were “confirmed” and 293 were “likely” to contain ENP. Product categories included sunscreens, cosmetics, health and fitness, automotive, food, home and garden, clothing and footwear, and eyeglass/lens coatings. Among the 27 different types of nanomaterials identified, SiO2 was predominant, followed by TiO2 and ZnO, Carbon Black, Ag, and Au. The amounts of ENP released into the aquatic system, which was estimated on the basis of typical product use, ENP concentration in the product, daily use quantity, release factor, and market share, were in the range of several hundred tons per year. As these quantities are likely to increase, it will be important to further study the fate of ENP that reach the aquatic environment in Singapore.

  16. Influence of environmental parameters and of their interactions on the release of metal(loid)s from a construction material in hydraulic engineering

    International Nuclear Information System (INIS)

    Schmukat, A.; Duester, L.; Goryunova, E.; Ecker, D.; Heininger, P.; Ternes, T.A.

    2016-01-01

    Highlights: • DoE supported multi-factorial study on the metal(loid) release from copper slag. • Interactions of four parameters were studied and weighted. • An effective separation method between slag and sediment was established. • The metal(loid) partitioning between sediment, slag and eluent is described. • The knowledge on the potential environmental impact of copper slag is increased. - Abstract: Besides the leaching behaviour of a construction material under standardised test-specific conditions with laboratory water, for some construction materials it is advisable to test their environmental behaviour also under close to end use conditions. The envisaged end use combined with the product characteristics (e.g. mineral phases) is decisive for the choice of environmental factors that may change the release of substance that potentially cause adverse environmental effects (e.g. fertilisation or ecotoxicity). At the moment an experimental link is missing between mono-factorial standardised test systems and non standardised complex incubation experiments such as mesocosms which are closer to environmental conditions. Multi-factorial batch experiments may have the potential to close the gap. To verify this, batch experiments with copper slag were performed which is used as armour stones in hydraulic engineering. Design of experiments (DoE) was applied to evaluate the impact of pH, ionic strength, temperature and sediment content on the release of As, Cu, Mo, Ni, Pb, Sb and Zn. The study shows that release and sediment-eluent partitioning of metal(loid)s are impacted by interactions between the studied factors. Under the prevalent test conditions sediment acts as a sink enhancing most strongly the release of elements from the material.

  17. Influence of environmental parameters and of their interactions on the release of metal(loid)s from a construction material in hydraulic engineering

    Energy Technology Data Exchange (ETDEWEB)

    Schmukat, A., E-mail: schmukat@harzwasserwerke.de [Harzwasserwerke GmbH, Zur Granetalsperre 8, 38685 Langelsheim (Germany); Federal Institute of Hydrology, Department of Aquatic Chemistry, Am Mainzer Tor 1, 56068 Koblenz (Germany); Duester, L. [Federal Institute of Hydrology, Department of Aquatic Chemistry, Am Mainzer Tor 1, 56068 Koblenz (Germany); Goryunova, E. [Federal Institute of Hydrology, Department of Aquatic Chemistry, Am Mainzer Tor 1, 56068 Koblenz (Germany); KAPP-Chemie GmbH & Co. KG, Industriestr. 2-4, 56357 Miehlen (Germany); Ecker, D.; Heininger, P.; Ternes, T.A. [Federal Institute of Hydrology, Department of Aquatic Chemistry, Am Mainzer Tor 1, 56068 Koblenz (Germany)

    2016-03-05

    Highlights: • DoE supported multi-factorial study on the metal(loid) release from copper slag. • Interactions of four parameters were studied and weighted. • An effective separation method between slag and sediment was established. • The metal(loid) partitioning between sediment, slag and eluent is described. • The knowledge on the potential environmental impact of copper slag is increased. - Abstract: Besides the leaching behaviour of a construction material under standardised test-specific conditions with laboratory water, for some construction materials it is advisable to test their environmental behaviour also under close to end use conditions. The envisaged end use combined with the product characteristics (e.g. mineral phases) is decisive for the choice of environmental factors that may change the release of substance that potentially cause adverse environmental effects (e.g. fertilisation or ecotoxicity). At the moment an experimental link is missing between mono-factorial standardised test systems and non standardised complex incubation experiments such as mesocosms which are closer to environmental conditions. Multi-factorial batch experiments may have the potential to close the gap. To verify this, batch experiments with copper slag were performed which is used as armour stones in hydraulic engineering. Design of experiments (DoE) was applied to evaluate the impact of pH, ionic strength, temperature and sediment content on the release of As, Cu, Mo, Ni, Pb, Sb and Zn. The study shows that release and sediment-eluent partitioning of metal(loid)s are impacted by interactions between the studied factors. Under the prevalent test conditions sediment acts as a sink enhancing most strongly the release of elements from the material.

  18. A prediction of the UO2 fission gas release data of Bellamy and Rich using a model recently developed by combustion engineering

    International Nuclear Information System (INIS)

    Freeburn, H.R.; Pati, S.R.

    1983-01-01

    The trend in the Light Water Reactor industry to higher discharge burnups of UO 2 fuel rods has initiated the modification of existing fuel rod models to better account for high burnup effects. A model recently developed by Combustion Engineering, Inc. (C-E) for fission gas release from UO 2 fuel recognizes the separate effects of temperature-dependent and temperature-independent release mechanisms. This model accounts for a moderate burnup enhancement that is based on a concept of a saturation inventory existing for the intra- and inter-grannular storage of fission gas within the fuel pellet. The saturation inventory, as modelled, is strongly dependent on the local temperature and the changing grain size of the fuel with burnup. Although the fitting constants of the model were determined solely from more current gas release data from fuel more typical of the C-E product line, the model, nonetheless, provides an excellent prediction of the Bellamy and Rich data over the entire burnup range represented by the data (+-1.6% gas release at a 1σ level). The ability to obtain a good comparison with this data base provides additional support for the use of the particular separation of the effects of thermal diffusion and burnup enhancement on fission gas release that is embodied in the model. Furthermore, the degree of burnup enhancement in the model is believed to be moderate enough to suggest that this high burnup effect should not impede the extension of discharge burnup limits associated with current design fuel rods for Pressurized Water Reactors

  19. Level Recession Of Emissions Release By Motor-And-Tractor Diesel Engines Through The Application Of Water-Fuel Emulsions

    Science.gov (United States)

    Ivanov, A.; Chikishev, E.

    2017-01-01

    The paper is dedicated to a problem of environmental pollution by emissions of hazardous substances with the exhaust gases of internal combustion engines. It is found that application of water-fuel emulsions yields the best results in diesels where production of a qualitative carburetion is the main problem for the organization of working process. During pilot studies the composition of a water-fuel emulsion with the patent held is developed. The developed composition of a water-fuel emulsion provides its stability within 14-18 months depending on mass content of components in it while stability of emulsions’ analogues makes 8-12 months. The mode of operation of pilot unit is described. Methodology and results of pilot study of operation of diesel engine on a water-fuel emulsion are presented. Cutting time of droplet combustion of a water-fuel emulsion improves combustion efficiency and reduces carbon deposition (varnish) on working surfaces. Partial dismantling of the engine after its operating time during 60 engine hours has shown that there is a removal of a carbon deposition in cylinder-piston group which can be observed visually. It is found that for steady operation of the diesel and ensuring decrease in level of emission of hazardous substances the water-fuel emulsion with water concentration of 18-20% is optimal.

  20. Cell-surface engineering by a conjugation-and-release approach based on the formation and cleavage of oxime linkages upon mild electrochemical oxidation and reduction.

    Science.gov (United States)

    Pulsipher, Abigail; Dutta, Debjit; Luo, Wei; Yousaf, Muhammad N

    2014-09-01

    We report a strategy to rewire cell surfaces for the dynamic control of ligand composition on cell membranes and the modulation of cell-cell interactions to generate three-dimensional (3D) tissue structures applied to stem-cell differentiation, cell-surface tailoring, and tissue engineering. We tailored cell surfaces with bioorthogonal chemical groups on the basis of a liposome-fusion and -delivery method to create dynamic, electroactive, and switchable cell-tissue assemblies through chemistry involving chemoselective conjugation and release. Each step to modify the cell surface: activation, conjugation, release, and regeneration, can be monitored and modulated by noninvasive, label-free analytical techniques. We demonstrate the utility of this methodology by the conjugation and release of small molecules to and from cell surfaces and by the generation of 3D coculture spheroids and multilayered cell tissues that can be programmed to undergo assembly and disassembly on demand. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. A poly(glycerol sebacate)-coated mesoporous bioactive glass scaffold with adjustable mechanical strength, degradation rate, controlled-release and cell behavior for bone tissue engineering.

    Science.gov (United States)

    Lin, Dan; Yang, Kai; Tang, Wei; Liu, Yutong; Yuan, Yuan; Liu, Changsheng

    2015-07-01

    Various requirements in the field of tissue engineering have motivated the development of three-dimensional scaffold with adjustable physicochemical properties and biological functions. A series of multiparameter-adjustable mesoporous bioactive glass (MBG) scaffolds with uncrosslinked poly(glycerol sebacate) (PGS) coating was prepared in this article. MBG scaffold was prepared by a modified F127/PU co-templating process and then PGS was coated by a simple adsorption and lyophilization process. Through controlling macropore parameters and PGS coating amount, the mechanical strength, degradation rate, controlled-release and cell behavior of the composite scaffold could be modulated in a wide range. PGS coating successfully endowed MBG scaffold with improved toughness and adjustable mechanical strength covering the bearing range of trabecular bone (2-12MPa). Multilevel degradation rate of the scaffold and controlled-release rate of protein from mesopore could be achieved, with little impact on the protein activity owing to an "ultralow-solvent" coating and "nano-cavity entrapment" immobilization method. In vitro studies indicated that PGS coating promoted cell attachment and proliferation in a dose-dependent manner, without affecting the osteogenic induction capacity of MBG substrate. These results first provide strong evidence that uncrosslinked PGS might also yield extraordinary achievements in traditional MBG scaffold. With the multiparameter adjustability, the composite MBG/PGS scaffolds would have a hopeful prospect in bone tissue engineering. The design considerations and coating method of this study can also be extended to other ceramic-based artificial scaffolds and are expected to provide new thoughts on development of future tissue engineering materials. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Medical Significance of Microorganisms in Spacecraft Environment

    Science.gov (United States)

    Pierson, Duane L.; Ott, C. Mark

    2007-01-01

    Microorganisms can spoil food supplies, contaminate drinking water, release noxious volatile compounds, initiate allergic responses, contaminate the environment, and cause infectious diseases. International acceptability limits have been established for bacterial and fungal contaminants in air and on surfaces, and environmental monitoring is conducted to ensure compliance. Allowable levels of microorganism in water and food have also been established. Environmental monitoring of the space shuttle, the Mir, and the ISS have allowed for some general conclusions. Generally, the bacteria found in air and on interior surfaces are largely of human origin such as Staphylococcus spp., Micrococcus spp. Common environmental genera such as Bacillus spp. are the most commonly isolated bacteria from all spacecraft. Yeast species associated with humans such as Candida spp. are commonly found. Aspergillus spp., Penicillium spp., and Cladosporium spp. are the most commonly isolated filamentous fungi. Microbial levels in the environment differ significantly depending upon humidity levels, condensate accumulation, and availability of carbon sources. However, human "normal flora" of bacteria and fungi can result in serious, life-threatening diseases if human immunity is compromised. Disease incidence is expected to increase as mission duration increases.

  3. Biodegradation of oil palm empty fruit bunch by composite micro-organisms

    International Nuclear Information System (INIS)

    Yusri Atan; Mat Rasol Awang; Mohammed Omar; Azizah Hashim; Tamikazu Kume; Shoji Hashimoto

    1998-01-01

    A comparison study on the comparative biodegradation ability on EFB by five groups of composite micro-organisms [Organomine, Thomas, Ohres C, Ohres II and micro-organisms from POME (palm oil mill effluent)] has been performed with the aim of producing a compost at a faster rate than that by natural biodegradation. The experiment was carried out by mixing 50 gram EFB (dry weight basis) with 3% ammonium sulphate to which was added 1% composite micro-organisms and water to produce a composting media of moisture content about 60%. Respiration of composite micro-organisms as well as from decomposition of EFB releasing CO sub 2. The choice of useful micro-organisms was based on its ability to degrade EFB as reflected by higher evolution rate of CO sub 2 released and retaining higher percentage of nitrogen in the final product

  4. Mechanical properties, biological activity and protein controlled release by poly(vinyl alcohol)–bioglass/chitosan–collagen composite scaffolds: A bone tissue engineering applications

    Energy Technology Data Exchange (ETDEWEB)

    Pon-On, Weeraphat, E-mail: fsciwpp@ku.ac.th [Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900 (Thailand); Charoenphandhu, Narattaphol; Teerapornpuntakit, Jarinthorn; Thongbunchoo, Jirawan; Krishnamra, Nateetip [Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University (Thailand); Department of Physiology, Faculty of Science, Mahidol University (Thailand); Tang, I-Ming [ThEP Center, Commission of Higher Education, 328 Si Ayutthaya Rd. (Thailand); Department of Materials Science, Faculty of Science, Kasetsart University, Bangkok 10900 (Thailand)

    2014-05-01

    In the present study, composite scaffolds made with different weight ratios (0.5:1, 1:1 and 2:1) of bioactive glass (15Ca:80Si:5P) (BG)/polyvinyl alcohol (PVA) (PVABG) and chitosan (Chi)/collagen (Col) (ChiCol) were prepared by three mechanical freeze–thaw followed by freeze-drying to obtain the porous scaffolds. The mechanical properties and the in vitro biocompatibility of the composite scaffolds to simulated body fluid (SBF) and to rat osteoblast-like UMR-106 cells were investigated. The results from the studies indicated that the porosity and compressive strength were controlled by the weight ratio of PVABG:ChiCol. The highest compressive modulus of the composites made was 214.64 MPa which was for the 1:1 weight ratio PVABG:ChiCol. Mineralization study in SBF showed the formation of apatite crystals on the PVABG:ChiCol surface after 7 days of incubation. In vitro cell availability and proliferation tests confirmed the osteoblast attachment and growth on the PVABG:ChiCol surface. MTT and ALP tests on the 1:1 weight ratio PVABG:ChiCol composite indicated that the UMR-106 cells were viable. Alkaline phosphatase activity was found to increase with increasing culturing time. In addition, we showed the potential of PVABG:ChiCol drug delivery through PBS solution studies. 81.14% of BSA loading had been achieved and controlled release for over four weeks was observed. Our results indicated that the PVABG:ChiCol composites, especially the 1:1 weight ratio composite exhibited significantly improved mechanical, mineral deposition, biological properties and controlled release. This made them potential candidates for bone tissue engineering applications. - Graphical abstract: Mechanical properties, biological activity and protein controlled release by poly(vinyl alcohol)–bioglass/chitosan–collagen composite scaffolds: A bone tissue engineering applications. - Highlights: • Preparation of PVABG:ChiCol hybrid composites and their bioactivities • Mechanical

  5. Mechanical properties, biological activity and protein controlled release by poly(vinyl alcohol)–bioglass/chitosan–collagen composite scaffolds: A bone tissue engineering applications

    International Nuclear Information System (INIS)

    Pon-On, Weeraphat; Charoenphandhu, Narattaphol; Teerapornpuntakit, Jarinthorn; Thongbunchoo, Jirawan; Krishnamra, Nateetip; Tang, I-Ming

    2014-01-01

    In the present study, composite scaffolds made with different weight ratios (0.5:1, 1:1 and 2:1) of bioactive glass (15Ca:80Si:5P) (BG)/polyvinyl alcohol (PVA) (PVABG) and chitosan (Chi)/collagen (Col) (ChiCol) were prepared by three mechanical freeze–thaw followed by freeze-drying to obtain the porous scaffolds. The mechanical properties and the in vitro biocompatibility of the composite scaffolds to simulated body fluid (SBF) and to rat osteoblast-like UMR-106 cells were investigated. The results from the studies indicated that the porosity and compressive strength were controlled by the weight ratio of PVABG:ChiCol. The highest compressive modulus of the composites made was 214.64 MPa which was for the 1:1 weight ratio PVABG:ChiCol. Mineralization study in SBF showed the formation of apatite crystals on the PVABG:ChiCol surface after 7 days of incubation. In vitro cell availability and proliferation tests confirmed the osteoblast attachment and growth on the PVABG:ChiCol surface. MTT and ALP tests on the 1:1 weight ratio PVABG:ChiCol composite indicated that the UMR-106 cells were viable. Alkaline phosphatase activity was found to increase with increasing culturing time. In addition, we showed the potential of PVABG:ChiCol drug delivery through PBS solution studies. 81.14% of BSA loading had been achieved and controlled release for over four weeks was observed. Our results indicated that the PVABG:ChiCol composites, especially the 1:1 weight ratio composite exhibited significantly improved mechanical, mineral deposition, biological properties and controlled release. This made them potential candidates for bone tissue engineering applications. - Graphical abstract: Mechanical properties, biological activity and protein controlled release by poly(vinyl alcohol)–bioglass/chitosan–collagen composite scaffolds: A bone tissue engineering applications. - Highlights: • Preparation of PVABG:ChiCol hybrid composites and their bioactivities • Mechanical

  6. Effect of injection pressure on heat release rate and emissions in CI engine using orange skin powder diesel solution

    International Nuclear Information System (INIS)

    Purushothaman, K.; Nagarajan, G.

    2009-01-01

    Experiments have been conducted to study the effect of injection pressure on the combustion process and exhaust emissions of a direct injection diesel engine fueled with Orange Skin Powder Diesel Solution (OSPDS). Earlier investigation by the authors revealed that 30% OSPDS was optimum for better performance and emissions. In the present investigation the injection pressure was varied with 30% OSPDS and the combustion, performance and emissions characteristics were compared with those of diesel fuel. The different injection pressures studied were 215 bar, 235 bar and 255 bar. The results showed that the cylinder pressure with 30% OSPDS at 235 bar fuel injection pressure, was higher than that of diesel fuel as well as at other injection pressures. Similarly, the ignition delay was longer and with shorter combustion duration with 30% OSPDS at 235 bar injection pressure. The brake thermal efficiency was better at 235 bar than that of other fuel injection pressures with OSPDS and lower than that of diesel fuel. The NO x emission with 30% OSPDS was higher at 235 bar. The hydrocarbon and CO emissions were lower with 30% OSPDS at 235 bar. The smoke emission with 30% OSPDS was marginally lower at 235 bar and marginally higher at 215 bar than for diesel fuel. The combustion, performance and emission characteristics of the engine operating on the test fuels at 235 bar injection pressure were better than other injection pressures

  7. Experimental investigation of n-butanol/diesel fuel blends and n-butanol fumigation – Evaluation of engine performance, exhaust emissions, heat release and flammability analysis

    International Nuclear Information System (INIS)

    Şahin, Zehra; Durgun, Orhan; Aksu, Orhan N.

    2015-01-01

    Highlights: • n-Butanol/diesel fuel blends and n-butanol fumigation investigated experimentally. • Flammability analysis of n-butanol performed. • Smoke decreases significantly for n-butanol/diesel fuel blends and n-butanol fumigation. • HC emission increases significantly for n-butanol/diesel fuel blends and n-butanol fumigation. • 2% n-Butanol/diesel fuel blend decreases slightly BSFC. - Abstract: The aim of this paper is to investigate and compare the effects of n-butanol/diesel fuel blends (nBDFBs) and n-butanol fumigation (nBF) on the engine performance and exhaust emissions in a turbocharged automobile diesel engine. Also, evaluations based on heat release and flammability analysis have been done. Experiments have been performed for various n-nBDFBs and nBF at different engine speeds and loads. For nBDFBs and nBF tests; nB2, nB4 and nB6 and nBF2, nBF4 and nBF6n-butanol percentages were selected. Here, for example nB2 and nBF2 contains 2% n-butanol and 98% diesel fuel by volume respectively. The test results showed that smoke decreases significantly by applying both of these two methods. However, decrement ratios of smoke for fumigation method are higher than that of blend method. NO x emission decreases for nB2, but it increases for nB4 and nB6 at selected engine speeds and loads. NO x emission decreases generally for nBF. For nB2 and nB4, BSFC decreases slightly but it increases for nB6. For nBF, BSFC increases at all of the test conditions. Adding n-butanol to diesel fuel becomes expensive for two methods. For nBDFBs, heat release rate (HRR) diagrams exhibit similar typical characteristic to NDF. However, for nBF, HRR shows slightly different pattern from NDF and a double peak is observed in the HRR diagram. The first peak occurs earlier than NDF and the second peak takes places later. In addition, this diagram shows that the first peak becomes larger and the second peak diminishes as n-butanol ratio is increased. Because of pilot injection of

  8. Biofuel production by recombinant microorganisms

    Science.gov (United States)

    Liao, James C.; Atsumi, Shota; Cann, Anthony F.

    2017-07-04

    Provided herein are metabolically-modified microorganisms useful for producing biofuels. More specifically, provided herein are methods of producing high alcohols including isobutanol, 1-butanol, 1-propanol, 2-methyl-1-butanol, 3-methyl-1-butanol and 2-phenylethanol from a suitable substrate.

  9. Airborne microorganisms from waste containers.

    Science.gov (United States)

    Jedlicka, Sabrina S; Stravitz, David M; Lyman, Charles E

    2012-01-01

    In physician's offices and biomedical labs, biological waste is handled every day. This waste is disposed of in waste containers designed for holding red autoclave bags. The containers used in these environments are closed hands-free containers, often with a step pedal. While these containers protect the user from surface-borne microorganisms, the containers may allow airborne microorganisms to escape via the open/close mechanism because of the air current produced upon open/close cycles. In this study, the air current was shown to be sufficient to allow airborne escape of microorganisms held in the container, including Aspergillus niger. However, bacterial cultures, such as Escherichia coli and Lactococcus lactis did not escape. This may be due to the choice of bacterial cultures and the absence of solid waste, such as dust or other particulate matter in the waste containers, that such strains of bacteria could travel on during aerosolization. We compared these results to those obtained using a re-designed receptacle, which mimimizes air currents, and detected no escaping microorganisms. This study highlights one potential source of airborne contamination in labs, hospitals, and other environments that dispose of biological waste.

  10. A bFGF-releasing silk/PLGA-based biohybrid scaffold for ligament/tendon tissue engineering using mesenchymal progenitor cells.

    Science.gov (United States)

    Sahoo, Sambit; Toh, Siew Lok; Goh, James C H

    2010-04-01

    An ideal scaffold that provides a combination of suitable mechanical properties along with biological signals is required for successful ligament/tendon regeneration in mesenchymal stem cell-based tissue engineering strategies. Among the various fibre-based scaffolds that have been used, hybrid fibrous scaffolds comprising both microfibres and nanofibres have been recently shown to be particularly promising. This study developed a biohybrid fibrous scaffold system by coating bioactive bFGF-releasing ultrafine PLGA fibres over mechanically robust slowly-degrading degummed knitted microfibrous silk scaffolds. On the ECM-like biomimetic architecture of ultrafine fibres, sustained release of bFGF mimicked the ECM in function, initially stimulating mesenchymal progenitor cell (MPC) proliferation, and subsequently, their tenogeneic differentiation. The biohybrid scaffold system not only facilitated MPC attachment and promoted cell proliferation, with cells growing both on ultrafine PLGA fibres and silk microfibres, but also stimulated tenogeneic differentiation of seeded MPCs. Upregulated gene expression of ligament/tendon-specific ECM proteins and increased collagen production likely contributed to enhancing mechanical properties of the constructs, generating a ligament/tendon analogue that has the potential to be used to repair injured ligaments/tendons. Copyright 2010 Elsevier Ltd. All rights reserved.

  11. Role of Microorganisms in the Removal of Radionuclides from Soil

    International Nuclear Information System (INIS)

    Bashandy, A.S.

    2007-01-01

    Resistance to radio nuclides and their accumulation by bacteria is a wide spread phenomenon that can be explored for the improvement of the environment. Metal resistant bacteria have developed very efficient and varying mechanisms for tolerating high levels of. toxic metals and thus hold potential for controlling heavy metal pollution. This property has been successfully applied for metal removal from soil. A total of 59 microorganisms were isolated from 5 locations in Sinai Desert. The microorganisms were examined for resistance to strontium, cobalt and cesium by spot technique on two kinds of media containing metals, Nutrient agar and King B agar. The resistant microorganisms were identified morphologically by Gram stain. The microorganisms were resistant to Sr and Cs at concentrations up to 200 mg/I and while Co proved to be toxic at a concentration of 100 mg/ I. The mechanisms of metal resistance to high concentrations were studied. Evidence show that the isolated microorganisms can uptake high concentrations of the studied elements. The results also, indicated that no binding proteins are released in the environment of the studied isolate

  12. Microorganisms .

    African Journals Online (AJOL)

    ) and heat/pH-shift treatments. This technique resulted in 47% enzyme yield with a purification fac- tor of 12. Technique II which involved two extraction steps by' aqueous two - phase system. (APS) coupled with UF resulted in 62 % enzyme ...

  13. An engineered pathway for glyoxylate metabolism in tobacco plants aimed to avoid the release of ammonia in photorespiration

    Directory of Open Access Journals (Sweden)

    Carvalho Josirley de FC

    2011-11-01

    Full Text Available Abstract Background The photorespiratory nitrogen cycle in C3 plants involves an extensive diversion of carbon and nitrogen away from the direct pathways of assimilation. The liberated ammonia is re-assimilated, but up to 25% of the carbon may be released into the atmosphere as CO2. Because of the loss of CO2 and high energy costs, there has been considerable interest in attempts to decrease the flux through the cycle in C3 plants. Transgenic tobacco plants were generated that contained the genes gcl and hyi from E. coli encoding glyoxylate carboligase (EC 4.1.1.47 and hydroxypyruvate isomerase (EC 5.3.1.22 respectively, targeted to the peroxisomes. It was presumed that the two enzymes could work together and compete with the aminotransferases that convert glyoxylate to glycine, thus avoiding ammonia production in the photorespiratory nitrogen cycle. Results When grown in ambient air, but not in elevated CO2, the transgenic tobacco lines had a distinctive phenotype of necrotic lesions on the leaves. Three of the six lines chosen for a detailed study contained single copies of the gcl gene, two contained single copies of both the gcl and hyi genes and one line contained multiple copies of both gcl and hyi genes. The gcl protein was detected in the five transgenic lines containing single copies of the gcl gene but hyi protein was not detected in any of the transgenic lines. The content of soluble amino acids including glycine and serine, was generally increased in the transgenic lines growing in air, when compared to the wild type. The content of soluble sugars, glucose, fructose and sucrose in the shoot was decreased in transgenic lines growing in air, consistent with decreased carbon assimilation. Conclusions Tobacco plants have been generated that produce bacterial glyoxylate carboligase but not hydroxypyruvate isomerase. The transgenic plants exhibit a stress response when exposed to air, suggesting that some glyoxylate is diverted away from

  14. Microorganism Utilization for Synthetic Milk

    Science.gov (United States)

    Morford, Megan A.; Khodadad, Christina L.; Caro, Janicce I.; Spencer, LaShelle E.; Richards, Jeffery T.; Strayer, Richard F.; Birmele, Michele N.; Wheeler, Raymond M.

    2014-01-01

    A desired architecture for long duration spaceflight, like aboard the International Space Station or for future missions to Mars, is to provide a supply of fresh food crops for the astronauts. However, some crops can create a high proportion of inedible plant waste. The main goal of the Synthetic Biology project, Cow in a Column, was to produce the components of milk (sugar, lipid, protein) from inedible plant waste by utilizing microorganisms (fungi, yeast, bacteria). Of particular interest was utilizing the valuable polysaccharide, cellulose, found in plant waste, to naturally fuel-through microorganism cellular metabolism- the creation of sugar (glucose), lipid (milk fat), and protein (casein) in order to produce a synthetic edible food product. Environmental conditions such as pH, temperature, carbon source, aeration, and choice microorganisms were optimized in the laboratory and the desired end-products, sugars and lipids, were analyzed. Trichoderma reesei, a known cellulolytic fungus, was utilized to drive the production of glucose, with the intent that the produced glucose would serve as the carbon source for milk fat production and be a substitute for the milk sugar lactose. Lipid production would be carried out by Rhodosporidium toruloides, yeast known to accumulate those lipids that are typically found in milk fat. Results showed that glucose and total lipid content were below what was expected during this phase of experimentation. In addition, individual analysis of six fatty acids revealed that the percentage of each fatty acid was lower than naturally produced bovine milk. Overall, this research indicates that microorganisms could be utilized to breakdown inedible solid waste to produce useable products. For future work, the production of the casein protein for milk would require the development of a genetically modified organism, which was beyond the scope of the original project. Additional trials would be needed to further refine the required

  15. The useful micro-organism

    International Nuclear Information System (INIS)

    1970-01-01

    Can man survive civilization? Academician Ivan Malek, Director of the Institute of Microbiology in Prague, a member of the Agency's Scientific Advisory Committee and for many years an adviser to the Food and Agriculture Organization, the World Health Organization and UNESCO, believes he can, But he also considers that if man is to survive he must study and use all the resources at his disposal - including the micro-organisms of the planet earth. (author)

  16. Secondary metabolites from marine microorganisms.

    Science.gov (United States)

    Kelecom, Alphonse

    2002-03-01

    After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.

  17. Secondary metabolites from marine microorganisms

    Directory of Open Access Journals (Sweden)

    KELECOM ALPHONSE

    2002-01-01

    Full Text Available After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.

  18. PROBIOTICS BASED ON TRANSGENIC MICROORGANISMS

    Directory of Open Access Journals (Sweden)

    S. А. Starovoitova

    2012-02-01

    Full Text Available Modern tendencies of recombinant microorganisms creation for obtaining on their basis a new effective biopreparations (probiotics with wider spectrum of biological and therapeutic properties were considered. A lot of attention was focused on the main genera of perspective bacteria for creation of recombinant probiotics particularly: Lactococcus, Bifidobac terium,Bacillus, Escherichia. The main created Ukrainian and foreign gene-modified strains, that are widely used today in creation of effective recombinant biopreparations were characterized. Some fundamental directions and methods of gene-modified strains obtaining, which are used in getting effective biopreparations that used for therapy and prophylactic illness were reported, under which this group of pharmaceutical drugs were not used earlier. The safety matters of probiotics using on basis of genemodified strains were examined. Medical and veterinary biopreparations on basis of recombinant microorganisms could be used directly and effectively for therapy and prophylaxis of different illness, beginning from disbacteriosis up to cardiovascular diseases. It is related with some probiotic microorganisms ability for lowering of serum cholesterol at the host organism.

  19. Transformation of the insecticide teflubenzuron by microorganisms

    NARCIS (Netherlands)

    Finkelstein, Z.I.; Baskunov, B.P.; Rietjens, I.M.C.M.; Boersma, M.G.; Vervoort, J.; Golovleva, L.A.

    2001-01-01

    Transformation of teflubenzuron, the active component in the insecticide commercialized as Nomolt, by soil microorganisms was studied. It was shown that microorganisms, belonging to Bacillus, Alcaligenes, Pseudomonas and Acinetobacter genera are capable to perform the hydrolytic cleavage of the

  20. 40 CFR 725.85 - Microorganism identity.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Microorganism identity. 725.85 Section... to Information § 725.85 Microorganism identity. (a) Claims applicable to the period prior to... specific microorganism identity at the time of submission of the information. This claim will apply only to...

  1. Mechanical properties, biological activity and protein controlled release by poly(vinyl alcohol)-bioglass/chitosan-collagen composite scaffolds: a bone tissue engineering applications.

    Science.gov (United States)

    Pon-On, Weeraphat; Charoenphandhu, Narattaphol; Teerapornpuntakit, Jarinthorn; Thongbunchoo, Jirawan; Krishnamra, Nateetip; Tang, I-Ming

    2014-05-01

    In the present study, composite scaffolds made with different weight ratios (0.5:1, 1:1 and 2:1) of bioactive glass (15Ca:80Si:5P) (BG)/polyvinyl alcohol (PVA) (PVABG) and chitosan (Chi)/collagen (Col) (ChiCol) were prepared by three mechanical freeze-thaw followed by freeze-drying to obtain the porous scaffolds. The mechanical properties and the in vitro biocompatibility of the composite scaffolds to simulated body fluid (SBF) and to rat osteoblast-like UMR-106 cells were investigated. The results from the studies indicated that the porosity and compressive strength were controlled by the weight ratio of PVABG:ChiCol. The highest compressive modulus of the composites made was 214.64 MPa which was for the 1:1 weight ratio PVABG:ChiCol. Mineralization study in SBF showed the formation of apatite crystals on the PVABG:ChiCol surface after 7 days of incubation. In vitro cell availability and proliferation tests confirmed the osteoblast attachment and growth on the PVABG:ChiCol surface. MTT and ALP tests on the 1:1 weight ratio PVABG:ChiCol composite indicated that the UMR-106 cells were viable. Alkaline phosphatase activity was found to increase with increasing culturing time. In addition, we showed the potential of PVABG:ChiCol drug delivery through PBS solution studies. 81.14% of BSA loading had been achieved and controlled release for over four weeks was observed. Our results indicated that the PVABG:ChiCol composites, especially the 1:1 weight ratio composite exhibited significantly improved mechanical, mineral deposition, biological properties and controlled release. This made them potential candidates for bone tissue engineering applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Cigarette company trade secrets are not secret: an analysis of reverse engineering reports in internal tobacco industry documents released as a result of litigation.

    Science.gov (United States)

    Velicer, Clayton; Lempert, Lauren K; Glantz, Stanton

    2015-09-01

    Use previously secret tobacco industry documents to assess tobacco companies' routine claims of trade secret protection for information on cigarette ingredients, additives and construction made to regulatory agencies, as well as the companies' refusal to publicly disclose this information. We analysed previously secret tobacco industry documents available at (http://legacy.library.ucsf.edu) to identify 100 examples of seven major tobacco companies' reverse engineering of their competitors' brands between 1937 and 2001. These reverse engineering reports contain detailed data for 142 different measurements for at least two companies, including physical parameters of the cigarettes, tobacco types, humectants, additives, flavourings, and smoke constituents of competitors' cigarettes. These 100 documents were distributed to 564 employees, including top managers in domestic and foreign offices across multiple departments, including executive leadership, research and design, product development, marketing and legal. These documents reported new competitors' products, measured ingredient changes over time, and informed companies' decisions regarding ingredients in their own products. Because cigarette companies routinely analyse their competitors' cigarettes in great detail, this information is neither secret nor commercially valuable and, thus, does not meet the legal definition of a 'trade secret.' This information is only being kept 'secret' from the people consuming cigarettes and the scientific community. Public agencies should release this detailed information because it would provide valuable information about how ingredients affect addictiveness and toxicity, and would help the public health community and consumers better understand the impact of cigarette design on human health. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  3. Effects of Atrazine on Soil Microorganisms

    Directory of Open Access Journals (Sweden)

    Ljiljana Radivojević

    2006-01-01

    Full Text Available Effects of the herbicide atrazine on soil microorganisms was investigated. Trials were set up in laboratory, on a clay loam soil. Atrazine was applied at 8.0, 40.0 and 80.0 mg/kg soil rates. The abundance of total microorganisms, fungi, actinomycetes, cellulolytic microorganisms and amino-heterotrophs was recorded. Soil samples were collected 1, 7, 14, 21, 30 and 60 days after atrazine treatment for microbiological analyses.The results showed that the intensity of atrazine effect on soil microorganisms depended on treatment rate, exposure time and group of microorganisms. Atrazine had an inhibiting effect on cellulolytic microorganisms and amino-heterotrophs. Initially, it inhibited fungiand actinomycetes but its effect turned into a stimulating one once a population recovered. Atrazine had a stimulating effect on total abundance of microorganisms.

  4. Marine microorganisms. Umi no biseibutsu

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, U. (Hiroshima University, Hiroshima (Japan). Faculty of Applied Biological Science)

    1992-11-10

    This paper explains properties, interactions, and activities of marine microorganisms. Marine bacteria include bacteria of vibrio family of arteromonas genus, luminous bacteria, and aerobic photosynthetic bacteria. Majority of marine bacteria is halophilic, and many proliferate at 5[degree]C or lower. Some of them can proliferate at 20[degree]C to 30[degree]C, or as high temperature as 80[degree]C and higher. Spongiaria and tumicata have many symbiotic microorganisms, and genes equivalent to luminous bacteria genes were discovered in DNA of light emitting organs in luminous fishes. It was verified that animal groups in upwelling zones are supported by bacteria that assimilate inorganics supplied from ocean bottoms. Marine bacteria decompose almost all of organics brought in from land to sea, and those produced in sea. Marine bacteria engage in complex interrelations with other organisms for competition, antagonism, parasitism, and symbiosis. The bacteria make antibacterial substances, anti-algae bacteria, enzyme inhibitors, toxins, pharmacologically active substances, and such physiologically active substances as deposition promoting substances to undersea structures including shells and barnacles, and deposition blocking substances. 53 refs., 3 figs.

  5. Study of radioresistance of microorganisms

    International Nuclear Information System (INIS)

    Olbrichova, D.

    1983-01-01

    Strain radiosensitivity was evaluated on the basis of the determination of inactivation curve parameters and the determination of the D 10 value. The course of curves was investigated for two 60 Co sources, RCHM-gamma-20 (USSR) with an activity of 2.54x10 14 Bq and AECL (type J-6000, Canada) with an activity of 4.92x10 16 Bq. The curve parameters were determined for microorganisms in buffer medium and for cultures in dehydrated condition. Coccus germs were irradiated with doses of 1, 2, 3, 4, 5 and 6 kGy and aerobic sporulates with doses of 3, 6, 9, 12 and 15 kGy. For comparing the resistance of isolated strains the t-test was used. The most resistant of the isolated strains were Bacillus cereus, Bacillus subtilis, Bacillus pumilus and Bacillus megatherium. (E.S.)

  6. Functional Basis of Microorganism Classification.

    Science.gov (United States)

    Zhu, Chengsheng; Delmont, Tom O; Vogel, Timothy M; Bromberg, Yana

    2015-08-01

    Correctly identifying nearest "neighbors" of a given microorganism is important in industrial and clinical applications where close relationships imply similar treatment. Microbial classification based on similarity of physiological and genetic organism traits (polyphasic similarity) is experimentally difficult and, arguably, subjective. Evolutionary relatedness, inferred from phylogenetic markers, facilitates classification but does not guarantee functional identity between members of the same taxon or lack of similarity between different taxa. Using over thirteen hundred sequenced bacterial genomes, we built a novel function-based microorganism classification scheme, functional-repertoire similarity-based organism network (FuSiON; flattened to fusion). Our scheme is phenetic, based on a network of quantitatively defined organism relationships across the known prokaryotic space. It correlates significantly with the current taxonomy, but the observed discrepancies reveal both (1) the inconsistency of functional diversity levels among different taxa and (2) an (unsurprising) bias towards prioritizing, for classification purposes, relatively minor traits of particular interest to humans. Our dynamic network-based organism classification is independent of the arbitrary pairwise organism similarity cut-offs traditionally applied to establish taxonomic identity. Instead, it reveals natural, functionally defined organism groupings and is thus robust in handling organism diversity. Additionally, fusion can use organism meta-data to highlight the specific environmental factors that drive microbial diversification. Our approach provides a complementary view to cladistic assignments and holds important clues for further exploration of microbial lifestyles. Fusion is a more practical fit for biomedical, industrial, and ecological applications, as many of these rely on understanding the functional capabilities of the microbes in their environment and are less concerned with

  7. Functional Basis of Microorganism Classification

    Science.gov (United States)

    Zhu, Chengsheng; Delmont, Tom O.; Vogel, Timothy M.; Bromberg, Yana

    2015-01-01

    Correctly identifying nearest “neighbors” of a given microorganism is important in industrial and clinical applications where close relationships imply similar treatment. Microbial classification based on similarity of physiological and genetic organism traits (polyphasic similarity) is experimentally difficult and, arguably, subjective. Evolutionary relatedness, inferred from phylogenetic markers, facilitates classification but does not guarantee functional identity between members of the same taxon or lack of similarity between different taxa. Using over thirteen hundred sequenced bacterial genomes, we built a novel function-based microorganism classification scheme, functional-repertoire similarity-based organism network (FuSiON; flattened to fusion). Our scheme is phenetic, based on a network of quantitatively defined organism relationships across the known prokaryotic space. It correlates significantly with the current taxonomy, but the observed discrepancies reveal both (1) the inconsistency of functional diversity levels among different taxa and (2) an (unsurprising) bias towards prioritizing, for classification purposes, relatively minor traits of particular interest to humans. Our dynamic network-based organism classification is independent of the arbitrary pairwise organism similarity cut-offs traditionally applied to establish taxonomic identity. Instead, it reveals natural, functionally defined organism groupings and is thus robust in handling organism diversity. Additionally, fusion can use organism meta-data to highlight the specific environmental factors that drive microbial diversification. Our approach provides a complementary view to cladistic assignments and holds important clues for further exploration of microbial lifestyles. Fusion is a more practical fit for biomedical, industrial, and ecological applications, as many of these rely on understanding the functional capabilities of the microbes in their environment and are less concerned

  8. Effects of intratracheally instilled laser printer-emitted engineered nanoparticles in a mouse model: A case study of toxicological implications from nanomaterials released during consumer use.

    Science.gov (United States)

    Pirela, Sandra V; Lu, Xiaoyan; Miousse, Isabelle; Sisler, Jennifer D; Qian, Yong; Guo, Nancy; Koturbash, Igor; Castranova, Vincent; Thomas, Treye; Godleski, John; Demokritou, Philip

    2016-01-01

    Incorporation of engineered nanomaterials (ENMs) into toners used in laser printers has led to countless quality and performance improvements. However, the release of ENMs during printing (consumer use) has raised concerns about their potential adverse health effects. The aim of this study was to use "real world" printer-emitted particles (PEPs), rather than raw toner powder, and assess the pulmonary responses following exposure by intratracheal instillation. Nine-week old male Balb/c mice were exposed to various doses of PEPs (0.5, 2.5 and 5 mg/kg body weight) by intratracheal instillation. These exposure doses are comparable to real world human inhalation exposures ranging from 13.7 to 141.9 h of printing. Toxicological parameters reflecting distinct mechanisms of action were evaluated, including lung membrane integrity, inflammation and regulation of DNA methylation patterns. Results from this in vivo toxicological analysis showed that while intratracheal instillation of PEPs caused no changes in the lung membrane integrity, there was a pulmonary immune response, indicated by an elevation in neutrophil and macrophage percentage over the vehicle control and low dose PEPs groups. Additionally, exposure to PEPs upregulated expression of the Ccl5 ( Rantes ), Nos1 and Ucp2 genes in the murine lung tissue and modified components of the DNA methylation machinery ( Dnmt3a ) and expression of transposable element (TE) LINE-1 compared to the control group. These genes are involved in both the repair process from oxidative damage and the initiation of immune responses to foreign pathogens. The results are in agreement with findings from previous in vitro cellular studies and suggest that PEPs may cause immune responses in addition to modifications in gene expression in the murine lung at doses that can be comparable to real world exposure scenarios, thereby raising concerns of deleterious health effects.

  9. Peat soils stabilization using Effective Microorganisms (EM)

    Science.gov (United States)

    Yusof, N. Z.; Samsuddin, N. S.; Hanif, M. F.; Syed Osman, S. B.

    2018-04-01

    Peat soil is known as geotechnical problematic soil since it is the softest soil having highly organic and moisture content which led to high compressibility, low shear strength and long-term settlement. The aim of this study was to obtain the stabilized peat soils using the Effective Microorganisms (EM). The volume of EM added and mixed with peat soils varied with 2%, 4%, 6%, 8% and 10% and then were cured for 7, 14 and 21 days. The experiment was done for uncontrolled and controlled moisture content. Prior conducting the main experiments, the physical properties such as moisture content, liquid limit, specific gravity, and plastic limit etc. were measure for raw peat samples. The Unconfined Compressive Strength (UCS) test was performed followed by regression analysis to check the effect of EM on the soil strength. Obtained results have shown that the mix design for controlled moisture contents showed the promising improvement in their compressive strength. The peat soil samples with 10% of EM shows the highest increment in UCS value and the percentage of increments are in the range of 44% to 65% after curing for 21 days. The regression analysis of the EM with the soil compressive strength showed that in controlled moisture conditions, EM significantly improved the soil stability as the value of R2 ranged between 0.97 – 0.78. The results have indicated that the addition of EM in peat soils provides significant improving in the strength of the soil as well as the other engineering properties.

  10. Tracking microorganisms and gene in the environment

    International Nuclear Information System (INIS)

    Atlas, R.M.; Sayler, G.S.

    1988-01-01

    Studies have been conducted to determine the sensitivities and limitations of various methods for determining the fate of genetically engineered microorganisms (GEMs) and their genes in the environment. Selective viable plate count procedures can be designed to detect the introduced organisms with high sensitivity; but they are restricted by potential mutations affecting the expression of the selective characteristic in the introduced organism, the occurrence of the particular selective characteristic in the indigenous organisms, and the need to culture the organism. The accuracy of this approach is greatly improved by colony hybridization procedures that use a specific gene probe to detect the introduced genes, but this approach is still only as sensitive as the plating procedure. Direct extraction of DNA from environmental samples, coupled with dot blot hybridization with radiolabeled probe DNA or solution hybridization, gives a high degree of both sensitivity and precision. This approach does not require culturing of the organism; and even if an introduced gene moves into a new organism or if the introduced organism is viable but nonculturable, the gene probe methods will detect the persistence of the introduced genes in the environment. Efficient direct DNA extraction methods have been developed and tested following in vitro experimental additions of GEMs to sediment and water samples

  11. Biochemistry engineering

    International Nuclear Information System (INIS)

    Jang, Ho Nam

    1993-01-01

    This deals with biochemistry engineering with nine chapters. It explains bionics on development and prospect, basics of life science on classification and structure, enzyme and metabolism, fundamentals of chemical engineering on viscosity, shear rate, PFR, CSTR, mixing, dispersion, measurement and response, Enzyme kinetics, competitive inhibition, pH profile, temperature profile, stoichiometry and fermentation kinetics, bio-reactor on Enzyme-reactor and microorganism-reactor, measurement and processing on data acquisition and data processing, separation and purification, waste water treatment and economics of bionics process.

  12. Effective Microorganisms: Myth or reality?

    Directory of Open Access Journals (Sweden)

    Aníbal F. Cóndor_Golec

    2013-04-01

    Full Text Available Th e increase in population has lead to intensifi cation of agricultural systems. Due to the use of pesticides the productivity of agricultural systems has increased but environmental deterioration and unsustainable systems are the consequences of these ways of management. Th e environmentally friendly Eff ective Microorganisms (EM technology claims an enormous amount of benefi ts (claimed by the companies. Th e use of EM as an addictive to manure or as a spray directly in the fi elds may increase the microfauna diversity of the soil and many benefi ts are derived from that increase. It seems that suffi cient information is available about this new technology. Th e aim of this project is to make an analysis of the literature about EM and answer the following questions: 1 how much is known about EM?, 2 how much research is done on EM?, 3 what are the principals of EM?, what are the socio-economic implications of EM?. We want to answer these questions in order to publish the facts about EM and its socio-economic implications.

  13. Biofouling of marbles by oxygenic photosynthetic microorganisms.

    Science.gov (United States)

    Karaca, Zeki; Öztürk, Ayten; Çolak, Emel

    2015-08-01

    Phototrophic microorganisms disfigure the surfaces of different types of stone. Stone structure is damaged by the activity of photoautotrophic and other microorganisms. However, to date few, investigations have been undertaken into the relationship between microorganisms and the properties of different types of marble. In this study, biological activity of photoautotrophic microorganisms on three types of marble (Yatagan White, Giallo Anticato and Afyon White) was investigated under laboratory conditions over a short period of time. The three types of marble supported the growth of phototrophic microbial communities on their outer and inner layers, turning their original colour from white to a yellowish green colour. The porosity of the marble types facilitated filamentous microbial growth in the presence of water. Scanning electron microscope analysis revealed the accumulation of aggregates such as small spherical, fibrillar, calcified globular bodies on the inner surfaces of the marbles. This suggests that the microscopic characteristics of particular marble types may stimulate the growth of certain types of microorganisms.

  14. Prediction of the UO/sub 2/ fission gas release data of Bellamy and Rich using a model recently developed by Combustion Engineering

    International Nuclear Information System (INIS)

    Freeburn, H.R.; Pati, S.R.

    1983-01-01

    The trend in the light water reactor industry to higher discharge burnups of UO/sub 2/ fuel rods has initiated the modification of existing fuel rod models to better account for high burnup effects. The degree to which fission gas release from UO/sub 2/ fuel is enhanced at higher burnup is being addressed in the process. Fission gas release modeling should include the separation of the individual effects of thermal diffusion and any burnup enhancement on the release. Although some modelers have interpreted the Bellamy and Rich data on fission gas release from UO/sub 2/ fuel in this fashion, they have assumed that below about 1250 0 C the gas release is not temperature-dependent, and this has led them to predict a very strong burnup enhancement of gas release above 20 MWd/kgU. More recent data, however, suggest that an appreciable amount of fission gas is released by a thermal diffusion mechanism at even lower temperatures and will add to the fission gas released due to the temperature-independent mechanisms of knockout and recoil

  15. A FIELD STUDY WITH GENETICALLY ENGINEERED ALFALFA INOCULATED WITH RECOMBINANT SINORHIZOBIUM MELILOTI: EFFECTS ON THE SOIL ECOSYSTEM

    Science.gov (United States)

    The agricultural use of genetically engineered plants and microorganisms has become increasingly common. Because genetically engineered plants and microorganisms can produce compounds foreign to their environment, there is concern that they may become established outside of thei...

  16. Proposal of the concept of selection of accidents that release large amounts of radioactive substances in the high temperature engineering test reactor

    International Nuclear Information System (INIS)

    Ono, Masato; Honda, Yuki; Takada, Shoji; Sawa, Kazuhiro

    2015-01-01

    In Position, construction and equipment of testing and research reactor to be subjected to the use standards for rules Article 53 (prevention of expansion of the accident to release a large amount of radioactive material) generation the frequency is a lower accident than design basis accident, when what is likely to release a large amount of radioactive material or radiation from the facility has occurred, and take the necessary measures in order to prevent the spread of the accident. There is provided a lower accident than frequency design basis accidents, for those that may release a large amount of radioactive material or radiation. (author)

  17. FRUTOS DE UCHUVA (PHYSALIS PERUVIANA L. ECOTIPO ‘COLOMBIA’ MÍNIMAMENTE PROCESADOS, ADICIONADOS CON MICROORGANISMOS PROBIÓTICOS UTILIZANDO LA INGENIERÍA DE MATRICES MINIMALLY PROCESSED CAPE GOOSEBERRY FRUITS (PHYSALIS PERUVIANA L. ‘COLOMBIAN’ ECOTYPE, ADDED WITH PROBIOTIC MICROORGANISMS USING THE MATRIX ENGINEERING

    Directory of Open Access Journals (Sweden)

    Zaira Tatiana Marin Arango

    2010-06-01

    Full Text Available El consumo de alimentos con microorganismos probióticos se ha incrementado en los últimos años debido a los beneficios saludables que estos proporcionan. El desarrollo de nuevos alimentos con probióticos diferentes a los productos lácteos, representa un reto para los investigadores y la industria. El presente estudio desarrolló a nivel piloto frutos de uchuva (Physalis peruviana L. mínimamente procesados con microorganismos probióticos, combinando el efecto benéfico de la cepa comercial Lactobacillus casei ATCC 393 con la aplicación de la Ingeniería de Matrices como metodología de obtención de alimentos funcionales. Se utiliza como líquido de impregnación una solución de glucosa al 14% p/p, con concentración inicial de inóculo de 5 en la escala de McFarland (1,5 x 109 UFC/mL. Las uchuvas recién impregnadas alcanzaron conteos de células viables de 1,95 ± 0,28 x 10(9 UFC/100 g de uchuva fresca (9,28 ± 0,06 x 109 ciclos log UFC/100 g uchuva fresca y a los 15 días de almacenamiento a 4 ºC los conteos de células viables fueron de 2,20 ± 0,59 x 10(9 UFC/100 g de uchuva fresca. (9,32 ± 0,14 x 109 ciclos log UFC/100 g uchuva fresca. Estos niveles de concentración de microorganismos probióticos en la uchuva son similares a los encontrados en los productos lácteos, como el yogurt, helados, quesos, entre otros.Food consumption with probiotic microorganisms has been increased in the last years due to its healthy benefits that they provide. The development of new food with probiotics apart from dairy products represents a challenge for both researchers and industry. The present study developed at pilot level cape gooseberry fruits (Physalis peruviana L. minimally processed with microorganisms probiotics, combining the beneficent effect of the strain commercial Lactobacillus casei ATCC 393 with the application of the matrix Engineering as methodology to obtain functional foods. As liquid of impregnation a solution of glucose at

  18. Calculation of the radiative properties of photosynthetic microorganisms

    International Nuclear Information System (INIS)

    Dauchet, Jérémi; Blanco, Stéphane; Cornet, Jean-François; Fournier, Richard

    2015-01-01

    photosynthetic bacteria, cyanobacteria and eukaryotic microalgae. The obtained results are in very good agreement with the experimental measurements when the shape of the microorganisms is well described (in comparison to the standard volume-equivalent sphere approximation). As a main perspective, the consideration of the helical shape of Arthrospira platensis appears to be a key to an accurate estimation of its radiative properties. On the whole, the presented methodological chain also appears of great interest for other scientific communities such as atmospheric science, oceanography, astrophysics and engineering

  19. Calculation of the radiative properties of photosynthetic microorganisms

    Science.gov (United States)

    Dauchet, Jérémi; Blanco, Stéphane; Cornet, Jean-François; Fournier, Richard

    2015-08-01

    photosynthetic bacteria, cyanobacteria and eukaryotic microalgae. The obtained results are in very good agreement with the experimental measurements when the shape of the microorganisms is well described (in comparison to the standard volume-equivalent sphere approximation). As a main perspective, the consideration of the helical shape of Arthrospira platensis appears to be a key to an accurate estimation of its radiative properties. On the whole, the presented methodological chain also appears of great interest for other scientific communities such as atmospheric science, oceanography, astrophysics and engineering.

  20. Calculated concentrations of any radionuclide deposited on the ground by release from underground nuclear detonations, tests of nuclear rockets, and tests of nuclear ramjet engines

    International Nuclear Information System (INIS)

    Hicks, H.G.

    1981-11-01

    This report presents calculated gamma radiation exposure rates and ground deposition of related radionuclides resulting from three types of event that deposited detectable radioactivity outside the Nevada Test Site complex, namely, underground nuclear detonations, tests of nuclear rocket engines and tests of nuclear ramjet engines

  1. Decomposition of diesel oil by various microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Suess, A; Netzsch-Lehner, A

    1969-01-01

    Previous experiments demonstrated the decomposition of diesel oil in different soils. In this experiment the decomposition of /sup 14/C-n-Hexadecane labelled diesel oil by special microorganisms was studied. The results were as follows: (1) In the experimental soils the microorganisms Mycoccus ruber, Mycobacterium luteum and Trichoderma hamatum are responsible for the diesel oil decomposition. (2) By adding microorganisms to the soil an increase of the decomposition rate was found only in the beginning of the experiments. (3) Maximum decomposition of diesel oil was reached 2-3 weeks after incubation.

  2. Sequential VEGF and BMP-2 releasing PLA-PEG-PLA scaffolds for bone tissue engineering: I. Design and in vitro tests.

    Science.gov (United States)

    Eğri, Sinan; Eczacıoğlu, Numan

    2017-03-01

    Biodegradable PLA-PEG-PLA block copolymers were synthesized with desired backbone structures and molecular weights using PEG20000. Rectangular scaffolds were prepared by freeze drying with or without using NaCl particles. Bone morphogenetic protein (BMP)-2 was loaded to the matrix after the scaffold formation for sustained release while vascular endothelial growth factor (VEGF) was loaded within the pores with gelatin solution. VEGF release was quite fast and almost 60% of it was released in 2 d. However, sequential - sustained released was observed for BMP-2 in the following few months. Corporation of VEGF/BMP-2 couple into the scaffolds increased the cell adhesion and proliferation. Neither significant cytotoxicity nor apoptosis/necrosis were observed.

  3. Release of E.coli D21g with transients in water content

    Science.gov (United States)

    Transients in water content are well known to mobilize microorganisms that are retained in the vadose zone. However, there is no consensus on the relative importance of drainage and imbibition events on microorganism release. To overcome this limitation, we have systematically studied the release o...

  4. Engineering microorganisms to increase ethanol production by metabolic redirection

    Science.gov (United States)

    Deng, Yu; Olson, Daniel G.; van Dijken, Johannes Pieter; Shaw, IV, Arthur J.; Argyros, Aaron; Barrett, Trisha; Caiazza, Nicky; Herring, Christopher D.; Rogers, Stephen R.; Agbogbo, Frank

    2017-10-31

    The present invention provides for the manipulation of carbon flux in a recombinant host cell to increase the formation of desirable products. The invention relates to cellulose-digesting organisms that have been genetically modified to allow the production of ethanol at a high yield by redirecting carbon flux at key steps of central metabolism.

  5. Tapping uncultured microorganisms through metagenomics for drug ...

    African Journals Online (AJOL)

    African Journal of Biotechnology ... Microorganisms are major source of bioactive natural products, and several ... This review highlights the recent methodologies, limitations, and applications of metagenomics for the discovery of new drugs.

  6. Detection of extracellular enzymatic activity in microorganisms ...

    African Journals Online (AJOL)

    sunny t

    2015-09-18

    Sep 18, 2015 ... microorganisms with all three enzymatic activities, thereby establishing these techniques as ... supplemented at 1% with vegetable oils, including olive (OLI) ..... cepacia lipase for biodiesel fuel production from soybean oil.

  7. Microorganisms' mediated reduction of β-ketoesters

    African Journals Online (AJOL)

    STORAGESEVER

    2008-10-20

    Oct 20, 2008 ... Whole cells usually express a multitude of enzymatic activities; therefore an ... Each microorganism was cultivated for the biomass development on specific medium ..... Ketoester reductase for conversion of keto acid esters to ...

  8. Detection of extracellular enzymatic activity in microorganisms ...

    African Journals Online (AJOL)

    Detection of extracellular enzymatic activity in microorganisms isolated from waste vegetable oil contaminated soil using plate methodologies. Eugenia G. Ortiz Lechuga, Isela Quintero Zapata, Katiushka Arévalo Niño ...

  9. Defensive properties of pyrrolizidine alkaloids against microorganisms

    NARCIS (Netherlands)

    Joosten, L.; Van Veen, J.A.

    2011-01-01

    The understanding of the selection factors that drive chemical diversification of secondary metabolites of constitutive defence systems in plants, such as pyrrolizidine alkaloids (PAs), is still incomplete. Historically, plants always have been confronted with microorganisms. Long before herbivores

  10. Genetic fingerprint of microorganisms associated with the ...

    Indian Academy of Sciences (India)

    inviting range of elements which microorganisms use in their ... ization and degradation of organic binders leading to struc- tural damage (Herrera et al. 2004). Microbial solubilization of materials involves the produc- ... architectural cement.

  11. Mechanisms of nickel toxicity in microorganisms

    OpenAIRE

    Macomber, Lee; Hausinger, Robert P.

    2011-01-01

    Nickel has long been known to be an important human toxicant, including having the ability to form carcinomas, but until recently nickel was believed to be an issue only to microorganisms living in nickel-rich serpentine soils or areas contaminated by industrial pollution. This assumption was overturned by the discovery of a nickel defense system (RcnR/RcnA) found in microorganisms that live in a wide range of environmental niches, suggesting that nickel homeostasis is a general biological co...

  12. Pathogenic and opportunistic microorganisms in caves

    Directory of Open Access Journals (Sweden)

    Sanchez-Moral Sergio

    2010-01-01

    Full Text Available With today’s leisure tourism, the frequency of visits to many caves makes it necessary to know about possible potentially pathogenic microorganisms in caves, determine their reservoirs, and inform the public about the consequences of such visits. Our data reveal that caves could be a potential danger to visitors because of the presence of opportunistic microorganisms, whose existence and possible development in humans is currently unknown.

  13. Molecular Breeding of Advanced Microorganisms for Biofuel Production

    Directory of Open Access Journals (Sweden)

    Hiroshi Sakuragi

    2011-01-01

    Full Text Available Large amounts of fossil fuels are consumed every day in spite of increasing environmental problems. To preserve the environment and construct a sustainable society, the use of biofuels derived from different kinds of biomass is being practiced worldwide. Although bioethanol has been largely produced, it commonly requires food crops such as corn and sugar cane as substrates. To develop a sustainable energy supply, cellulosic biomass should be used for bioethanol production instead of grain biomass. For this purpose, cell surface engineering technology is a very promising method. In biobutanol and biodiesel production, engineered host fermentation has attracted much attention; however, this method has many limitations such as low productivity and low solvent tolerance of microorganisms. Despite these problems, biofuels such as bioethanol, biobutanol, and biodiesel are potential energy sources that can help establish a sustainable society.

  14. Biogenic nanomaterials from photosynthetic microorganisms.

    Science.gov (United States)

    Jeffryes, Clayton; Agathos, Spiros N; Rorrer, Gregory

    2015-06-01

    The use of algal cell cultures represents a sustainable and environmentally friendly platform for the biogenic production of nanobiomaterials and biocatalysts. For example, advances in the production of biogeneic nanomaterials from algal cell cultures, such as crystalline β-chitin nanofibrils and gold and silver nanoparticles, could enable the 'green' production of biomaterials such as tissue-engineering scaffolds or drug carriers, supercapacitors and optoelectric materials. The in vivo functionalization, as well as newly demonstrated methods of production and modification, of biogenic diatom biosilica have led to the development of organic-inorganic hybrid catalytic systems as well as new biomaterials for drug delivery, biosensors and heavy-metal adsorbents. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Using microorganisms to recover metals

    International Nuclear Information System (INIS)

    Jeffers, T.H.

    1991-01-01

    Biological processes have been used for thousands of years to make cheese, wine, and beer. During the past few hundred years these processes have been employed to process sewage. Increasingly, microbes are being used to clean up a wide variety of toxic chemical wastes that have been dumped into the environment. Scientists are currently examining the possible use of microbes to detoxify naturally occurring toxic selenium-bearing water at the Kesterson Wildlife Refuge. The mining and minerals industries also use biological processes to remove impurities from ores, cut processing costs, and treat some metallic ores that previously were too difficult or too expensive to process by traditional methods. In this article, the term 'mining industry' applies to the extraction of ore whereas the term 'minerals industry' applies to processing the ore. Applications of biotechnology in the mining and minerals industries are expected to increase. The paper discusses the use of microbial leaching in the copper, uranium, gold, and manganese mining industries; treatments of mine wastes; the treatment of cyanide solution, and research into bioleaching, biosorption, and genetic engineering

  16. Modelling biocide release based on coating properties

    NARCIS (Netherlands)

    Erich, S.J.F.; Baukh, V.

    2016-01-01

    Growth of micro-organisms on coated substrates is a common problem, since it reduces the performance of materials, in terms of durability as well as aesthetics. In order to prevent microbial growth biocides are frequently added to coatings. Unfortunately, early release of these biocides reduces the

  17. Application of thermotolerant microorganisms for biofertilizer preparation.

    Science.gov (United States)

    Chen, Kuo-Shu; Lin, Yann-Shying; Yang, Shang-Shyng

    2007-12-01

    Intensive agriculture is practised in Taiwan, and compost application is very popular as a means of improving the soil physical properties and supplying plant nutrition. We tested the potential of inoculation with thermotolerant microorganisms to shorten the maturity and improve the quality of biofertilizer prepared by composting. Thermotolerant microorganisms were isolated from compost and reinoculated for the preparation of biofertilizer. The physical, chemical and biological properties of the biofertilizer were determined during composting. The effects of biofertilizer application on the growth and yield of rape were also studied. Among 3823 colonies of thermotolerant microorganisms, Streptomyces thermonitrificans NTU-88, Streptococcus sp. NTU-130 and Aspergillus fumigatus NTU-132 exhibited high growth rates and cellulolytic and proteolytic activities. When a mixture of rice straw and swine manure were inoculated with these isolates and composted for 61 days, substrate temperature increased initially and then decreased gradually during composting. Substrate pH increased from 7.3 to 8.5. Microbial inoculation enhanced the rate of maturity, and increased the content of ash and total and immobilized nitrogen, improved the germination rate of alfalfa seed, and decreased the content of total organic carbon and the carbon/nitrogen ratio. Biofertilizer application increased the growth and yield of rape. Inoculation of thermotolerant and thermophilic microorganisms to agricultural waste for biofertilizer preparation enhances the rate of maturity and improves the quality of the resulting biofertilizer. Inoculation of appropriate microorganisms in biofertilizer preparation might be usefully applied to agricultural situations.

  18. Microorganism identification technique using radioactive and fluorescent agent

    International Nuclear Information System (INIS)

    Silman, R.E.

    1983-01-01

    A method for identifying microorganisms is claimed. An emissive agent is added to a specimen of microorganisms to produce a mix of emissive products. These products are detected and characteristic pattern functioning as an identifier for the microorganisms is derived. The identifier is then compared with identifiers representing known microorganisms

  19. Food fermentations: Microorganisms with technological beneficial use

    DEFF Research Database (Denmark)

    Bourdichon, François; Casaregola, Serge; Farrokh, Choreh

    2012-01-01

    Microbial food cultures have directly or indirectly come under various regulatory frameworks in the course of the last decades. Several of those regulatory frameworks put emphasis on “the history of use”, “traditional food”, or “general recognition of safety”. Authoritative lists of microorganism......, legumes, cereals, beverages, and vinegar). We have also reviewed and updated the taxonomy of the microorganisms used in food fermentations in order to bring the taxonomy in agreement with the current standing in nomenclature....... cultures in practical use. However, as the focus mainly was on commercially available dairy cultures, there was an unmet need for a list with a wider scope. We present an updated inventory of microorganisms used in food fermentations covering a wide range of food matrices (dairy, meat, fish, vegetables...

  20. Biosurfactants, bioemulsifiers and exopolysaccharides from marine microorganisms.

    Science.gov (United States)

    Satpute, Surekha K; Banat, Ibrahim M; Dhakephalkar, Prashant K; Banpurkar, Arun G; Chopade, Balu A

    2010-01-01

    Marine biosphere offers wealthy flora and fauna, which represents a vast natural resource of imperative functional commercial grade products. Among the various bioactive compounds, biosurfactant (BS)/bioemulsifiers (BE) are attracting major interest and attention due to their structural and functional diversity. The versatile properties of surface active molecules find numerous applications in various industries. Marine microorganisms such as Acinetobacter, Arthrobacter, Pseudomonas, Halomonas, Myroides, Corynebacteria, Bacillus, Alteromonas sp. have been studied for production of BS/BE and exopolysaccharides (EPS). Due to the enormity of marine biosphere, most of the marine microbial world remains unexplored. The discovery of potent BS/BE producing marine microorganism would enhance the use of environmental biodegradable surface active molecule and hopefully reduce total dependence or number of new application oriented towards the chemical synthetic surfactant industry. Our present review gives comprehensive information on BS/BE which has been reported to be produced by marine microorganisms and their possible potential future applications.

  1. Engineering Saccharomyces cerevisiae To Release 3-Mercaptohexan-1-ol during Fermentation through Overexpression of an S. cerevisiae Gene, STR3, for Improvement of Wine Aroma▿

    Science.gov (United States)

    Holt, Sylvester; Cordente, Antonio G.; Williams, Simon J.; Capone, Dimitra L.; Jitjaroen, Wanphen; Menz, Ian R.; Curtin, Chris; Anderson, Peter A.

    2011-01-01

    Sulfur-containing aroma compounds are key contributors to the flavor of a diverse range of foods and beverages. The tropical fruit characters of Vitis vinifera L. cv. Sauvignon blanc wines are attributed to the presence of the aromatic thiols 3-mercaptohexan-1-ol (3MH), 3-mercaptohexan-1-ol-acetate, and 4-mercapto-4-methylpentan-2-one (4MMP). These volatile thiols are found in small amounts in grape juice and are formed from nonvolatile cysteinylated precursors during fermentation. In this study, we overexpressed a Saccharomyces cerevisiae gene, STR3, which led to an increase in 3MH release during fermentation of a V. vinifera L. cv. Sauvignon blanc juice. Characterization of the enzymatic properties of Str3p confirmed it to be a pyridoxal-5′-phosphate-dependent cystathionine β-lyase, and we demonstrated that this enzyme was able to cleave the cysteinylated precursors of 3MH and 4MMP to release the free thiols. These data provide direct evidence for a yeast enzyme able to release aromatic thiols in vitro that can be applied in the development of self-cloned yeast to enhance wine flavor. PMID:21478306

  2. Risk Assessment of Genetically Modified Microorganisms

    DEFF Research Database (Denmark)

    Jacobsen, B. L.; Wilcks, Andrea

    2001-01-01

    the industry, national administration and research institutions were gathered to discuss which elements should be considered in a risk assessment of genetically modified microorganisms used as food or food ingredients. The existing EU and national regulations were presented, together with the experiences......The rapid development of recombinant DNA techniques for food organisms urges for an ongoing discussion on the risk assessment of both new as traditional use of microorganisms in food production. This report, supported by the Nordic Council of Ministers, is the result of a workshop where people from...... with risk assessment of these organisms in each Nordic country....

  3. Functional Properties of Microorganisms in Fermented Foods

    Directory of Open Access Journals (Sweden)

    Jyoti Prakash Tamang

    2016-04-01

    Full Text Available Fermented foods have unique functional properties imparting some health benefits to consumers due to presence of functional microorganisms, which possess probiotics properties, antimicrobial, antioxidant, peptide production, etc. Health benefits of some global fermented foods are synthesis of nutrients, prevention of cardiovascular disease, prevention of cancer, gastrointestinal disorders, allergic reactions, diabetes, among others. The present paper is aimed to review the information on some functional properties of the microorganisms associated with fermented foods and beverages, and their health-promoting benefits to consumers.

  4. Physiologically anaerobic microorganisms of the deep subsurface. Progress report, June 1, 1990--May 30, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, S.E. Jr.; Chung, K.T.

    1991-06-01

    This study seeks to determine numbers, diversity, and morphology of anaerobic microorganisms in 15 samples of subsurface material from the Idaho National Engineering Laboratory, in 18 samples from the Hanford Reservation and in 1 rock sample from the Nevada Test Site; set up long term experiments on the chemical activities of anaerobic microorganisms based on these same samples; work to improve methods for the micro-scale determination of in situ anaerobic microbial activity;and to begin to isolate anaerobes from these samples into axenic culture with identification of the axenic isolates.

  5. Localised controlled release of simvastatin from porous chitosan–gelatin scaffolds engrafted with simvastatin loaded PLGA-microparticles for bone tissue engineering application

    Energy Technology Data Exchange (ETDEWEB)

    Gentile, Piergiorgio [Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin (Italy); School of Clinical Dentistry, University of Sheffield, 19 Claremont Crescent, Sheffield (United Kingdom); Nandagiri, Vijay Kumar [Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin (Italy); School of Pharmacy, Royal College of Surgeons in Ireland, 123, St. Stephen Green, Dublin 2 (Ireland); Daly, Jacqueline [Division of Biology, Department of Anatomy, Royal College of Surgeons in Ireland, 123, St. Stephen Green, Dublin 2 (Ireland); Chiono, Valeria; Mattu, Clara; Tonda-Turo, Chiara; Ciardelli, Gianluca [Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin (Italy); Ramtoola, Zebunnissa, E-mail: zramtoola@rcsi.ie [School of Pharmacy, Royal College of Surgeons in Ireland, 123, St. Stephen Green, Dublin 2 (Ireland)

    2016-02-01

    Localised controlled release of simvastatin from porous freeze-dried chitosan–gelatin (CH–G) scaffolds was investigated by incorporating simvastatin loaded poly-(DL-lactide-co-glycolide) acid (PLGA) microparticles (MSIMs) into the scaffolds. MSIMs at 10% w/w simvastatin loading were prepared using a single emulsion-solvent evaporation method. The MSIM optimal amount to be incorporated into the scaffolds was selected by analysing the effect of embedding increasing amounts of blank PLGA microparticles (BL-MPs) on the scaffold physical properties and on the in vitro cell viability using a clonal human osteoblastic cell line (hFOB). Increasing the BL-MP content from 0% to 33.3% w/w showed a significant decrease in swelling degree (from 1245 ± 56% to 570 ± 35%). Scaffold pore size and distribution changed significantly as a function of BL-MP loading. Compressive modulus of scaffolds increased with increasing BL-MP amount up to 16.6% w/w (23.0 ± 1.0 kPa). No significant difference in cell viability was observed with increasing BL-MP loading. Based on these results, a content of 16.6% w/w MSIM particles was incorporated successfully in CH–G scaffolds, showing a controlled localised release of simvastatin able to influence the hFOB cell proliferation and the osteoblastic differentiation after 11 days. - Highlights: • Simvastatin loaded PLGA microparticle engrafted porous CH–G scaffolds were produced. • The microparticle optimal amount to be incorporated into the scaffolds was studied. • Physical properties of scaffolds changed as a function of microparticle loading. • The level of simvastatin released enhanced cell proliferation and mineralisation.

  6. Localised controlled release of simvastatin from porous chitosan–gelatin scaffolds engrafted with simvastatin loaded PLGA-microparticles for bone tissue engineering application

    International Nuclear Information System (INIS)

    Gentile, Piergiorgio; Nandagiri, Vijay Kumar; Daly, Jacqueline; Chiono, Valeria; Mattu, Clara; Tonda-Turo, Chiara; Ciardelli, Gianluca; Ramtoola, Zebunnissa

    2016-01-01

    Localised controlled release of simvastatin from porous freeze-dried chitosan–gelatin (CH–G) scaffolds was investigated by incorporating simvastatin loaded poly-(DL-lactide-co-glycolide) acid (PLGA) microparticles (MSIMs) into the scaffolds. MSIMs at 10% w/w simvastatin loading were prepared using a single emulsion-solvent evaporation method. The MSIM optimal amount to be incorporated into the scaffolds was selected by analysing the effect of embedding increasing amounts of blank PLGA microparticles (BL-MPs) on the scaffold physical properties and on the in vitro cell viability using a clonal human osteoblastic cell line (hFOB). Increasing the BL-MP content from 0% to 33.3% w/w showed a significant decrease in swelling degree (from 1245 ± 56% to 570 ± 35%). Scaffold pore size and distribution changed significantly as a function of BL-MP loading. Compressive modulus of scaffolds increased with increasing BL-MP amount up to 16.6% w/w (23.0 ± 1.0 kPa). No significant difference in cell viability was observed with increasing BL-MP loading. Based on these results, a content of 16.6% w/w MSIM particles was incorporated successfully in CH–G scaffolds, showing a controlled localised release of simvastatin able to influence the hFOB cell proliferation and the osteoblastic differentiation after 11 days. - Highlights: • Simvastatin loaded PLGA microparticle engrafted porous CH–G scaffolds were produced. • The microparticle optimal amount to be incorporated into the scaffolds was studied. • Physical properties of scaffolds changed as a function of microparticle loading. • The level of simvastatin released enhanced cell proliferation and mineralisation.

  7. Pesticides in Soil: Effects on Microorganisms

    Directory of Open Access Journals (Sweden)

    Ljiljana Radivojević

    2007-01-01

    Full Text Available Since their discovery to the present day, pesticides have been an inevitable segment of agricultural production and efforts have been made to synthesize compounds that would share a required efficacy along with selectivity, sufficient persistence on the object of protection and favourable toxicological and ecotoxicological characteristics so as to minimize their effect on the environment.When a pesticide gets into soil after application, it takes part in a number of physical, chemical and biological processes that depend not only on the compound itself, but a number of other factors as well, such as: physical, chemical and biological characteristics of soil; climatic factors, equipment used, method of application, method of storage, handling and disposal of waste, site characteristics (proximity of ground and underground waters, biodiversity and sensitivity of the environment. Microorganisms play an important role in pesticide degradation as they are able to utilize the biogenic elements from those compounds, as well as energy for their physiological processes. On the other hand, pesticides are more or less toxic substances that can have adverse effect on populations of microorganisms and prevent their development, reduce their abundance, deplete their taxonomic complexity and create communities with a lower level of diversity and reduced physiological activity.The article discusses complex interactions between pesticides and microorganisms in soil immediately after application and over the ensuing period. Data on changes in the abundance of some systematic and physiological groups of microorganisms, their microbial biomass and enzymatic activity caused under pesticide activity are discussed as indicators of these processes.

  8. [DIFFERENTIAL SENSITIVITY OF MICROORGANISMS TO POLYHEXAMETHYLENEGUANIDINE].

    Science.gov (United States)

    Lysytsya, A V; Mandygra, Y M; Bojko, O P; Romanishyna, O O; Mandygra, M S

    2015-01-01

    Factors identified that affect the sensitivity of microorganisms to polyhexamethyleneguanidine (PHMG). Salts of PHMG chloride, valerate, maleate, succinate was to use. Test strains of Esherichia coli, Staphylococcus aureus, Bacillus cereus, Leptospira interrogans, Paenibacillus larvae, Mycobacterium bovis, M. avium, M. fortuitum, Aspergillus niger and some strains of viruses are taken as objects of research. We have determined that the cytoplasm membrane phospholipids is main "target" for the polycation molecules of PHMG. A differential sensitivity of the microorganisms to this drug is primarily determined by relative amount of lipids in membrane and their accessibility. Such trends exist: increase the relative contents of anionic lipids and more negative surface electric potential of membrane, and reduction of the sizes fat acid remainder of lipids bring to increase of microorganism sensitivity. Types of anion salt PHMG just have a certain value. Biocide activity of PHMG chloride is more, than its salts with organic acid. Feasibility of combining PHMG with other biocides in the multicomponent disinfectants studied and analyzed. This combination does not lead to a significant increase in the sensitivity of microorganisms tested in most cases. Most species of pathogenic bacteria can be quickly neutralized by aqueous solutions of PHMG in less than 1% concentrations.

  9. Antibiotic Sensitivity Pattern of Microorganisms Isolated from ...

    African Journals Online (AJOL)

    Antibiotic sensitivity pattern of microorganisms isolated from smoked and frozen fishes sold in Benin and Warri metropolis were investigated. Adopting microbiological standard techniques, the results of the bacterial counts and fungal counts ranged from 5.4 x 106 (Ekpan market) to 25.1 x 106 (Ekpan market) and 1.1 x 105 ...

  10. Modelling the morphology of filamentous microorganisms

    DEFF Research Database (Denmark)

    Nielsen, Jens Bredal

    1996-01-01

    The rapid development in image analysis techniques has made it possible to study the growth kinetics of filamentous microorganisms in more detail than previously, However, owing to the many different processes that influence the morphology it is important to apply mathematical models to extract...

  11. Mechanisms of nickel toxicity in microorganisms

    Science.gov (United States)

    Macomber, Lee

    2014-01-01

    Summary Nickel has long been known to be an important human toxicant, including having the ability to form carcinomas, but until recently nickel was believed to be an issue only to microorganisms living in nickel-rich serpentine soils or areas contaminated by industrial pollution. This assumption was overturned by the discovery of a nickel defense system (RcnR/RcnA) found in microorganisms that live in a wide range of environmental niches, suggesting that nickel homeostasis is a general biological concern. To date, the mechanisms of nickel toxicity in microorganisms and higher eukaryotes are poorly understood. In this review, we summarize nickel homeostasis processes used by microorganisms and highlight in vivo and in vitro effects of exposure to elevated concentrations of nickel. On the basis of this evidence we propose four mechanisms of nickel toxicity: 1) nickel replaces the essential metal of metalloproteins, 2) nickel binds to catalytic residues of non-metalloenzymes; 3) nickel binds outside the catalytic site of an enzyme to inhibit allosterically, and 4) nickel indirectly causes oxidative stress. PMID:21799955

  12. False identification of other microorganisms as Staphylococcus ...

    African Journals Online (AJOL)

    Methods: 507 microorganisms which have been previously identified as S. aureus in 8 States in Southern Nigeria through characteristic morphology on blood agar, Gram staining, growth and fermentation on Mannitol Salt Agar and coagulase formation were collected. All the isolates were identified in this study through ...

  13. Host Defense against Opportunist Microorganisms Following Trauma.

    Science.gov (United States)

    1979-06-01

    Guide for Laboratory Animal, Resources, National Academy of Sciences - National Research Council. I ii t ___ ii A- KNOWLEDMENT The investigators express...and Candida albicans are the microorganisms which are most frequently associated with septic complica- tions in thermally injured patients. Management

  14. Ecophysiology of microorganisms in microbial elctrolysis cells

    NARCIS (Netherlands)

    Croese, E.

    2012-01-01

    One of the main challenges for improvement of the microbial electrolysis cell (MEC) has been the reduction of the cost of the cathode catalyst. As catalyst at the cathode, microorganisms offer great possibilities. Previous research has shown the principle possibilities for the biocathode for H2

  15. Ecology and metagenomics of soil microorganisms

    Czech Academy of Sciences Publication Activity Database

    Baldrian, Petr; Head, I. M.; Prosser, J. I.; Schloter, M.; Smalla, K.; Tebbe, C. C.

    2011-01-01

    Roč. 78, č. 1 (2011), s. 1-2 ISSN 0168-6496 R&D Projects: GA MŠk LC06066; GA MŠk(CZ) LA10001 Institutional research plan: CEZ:AV0Z50200510 Keywords : microorganism * bioremediation * biogenesis of soil Subject RIV: EE - Microbiology, Virology Impact factor: 3.408, year: 2011

  16. Novel genome alteration system for microorganisms

    NARCIS (Netherlands)

    Daran, J.G.; Geertman, J.M.; Bolat, I.

    2015-01-01

    The invention relates to a set of targeting constructs, comprising a first construct comprising a recognition site for an endonuclease, a first region of homology with a target gene of a microorganism, and a first part of a selection marker, and a second construct comprising a second part of the

  17. The influence of selected nanomaterials on microorganisms

    Czech Academy of Sciences Publication Activity Database

    Brandeburová, P.; Birošová, L.; Vojs, M.; Kromka, Alexander; Gál, M.; Tichý, J.; Híveš, J.; Mackul´ak, T.

    2017-01-01

    Roč. 148, č. 3 (2017), s. 525-530 ISSN 0026-9247 R&D Projects: GA ČR GA15-01687S Institutional support: RVO:68378271 Keywords : nanomaterials * nanotechnologies * microorganisms * toxicity Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 1.282, year: 2016

  18. Novel Industrial Enzymes from Uncultured Arctic Microorganisms

    DEFF Research Database (Denmark)

    Vester, Jan Kjølhede

    , and reduce the risk of contaminations. Cold- and alkaline-active enzymes can be found in microorganisms adapted to living in natural environments with these conditions, which are extremely rare but found in the unique ikaite columns from SW Greenland (4-6 °C, pH >10). It is estimated that less than 1...

  19. [Sorption of microorganisms by fiber materials].

    Science.gov (United States)

    Nikovskaia, G N; Gordienko, A S; Globa, L I

    1986-01-01

    Candida guilliermondii and Escherichia coli cells were adsorbed on glass and basalt fibres with a similar specific surface, but with a different charge. The quantity of adsorbed microorganisms did not depend on the type and charge of a fibre surface. However, cells were adsorbed faster and more firmly on positively charged and uncharged fibres than on negatively charged fibres.

  20. Doppler speedometer for micro-organisms

    International Nuclear Information System (INIS)

    Penkov, F.; Tuleushev, A.; Lisitsyn, V.; Kim, S.; Tuleushev, Yu.

    1996-01-01

    Objective of Investigations: Development and creation of the Doppler speedometer for micro-organisms which allows to evaluate, in a real temporal scale, variations in the state of water suspension of micro-organisms under the effect of chemical, physical and other external actions. Statement of the Problem The main problem is absence of reliable, accessible for users and simple, in view of application, Doppler speedometers for micro-organisms. Nevertheless, correlation Doppler spectrometry in the regime of heterodyning the supporting and cell-scattered laser radiation is welt known. The main idea is that the correlation function of photo-current pulses bears an information on the averages over the assembly of cell velocities. For solving the biological problems, construction of auto-correlation function in the real-time regime with the delay time values comprising, function in the real-time regime with the delay time values comprising, nearly, 100 me (10 khz) or higher is needed. Computers of high class manage this problem using but the program software. Due to this, one can simplify applications of the proposed techniques provided he creates the Doppler speedometer for micro-organism on a base of the P entium . Expected Result Manufactured operable mock-up of the Doppler speedometer for micro-organisms in a form of the auxiliary computer block which allows to receive an information, in the real time scale, on the results of external effects of various nature on the cell assembly in transparent medium with a small volume of the studied cell suspension

  1. Role of soil micro-organisms in the sorption of radionuclides in organic systems

    International Nuclear Information System (INIS)

    Parekh, N.R.; Potter, E.D.; Poskitt, J.M.; Dodd, B.A.; Sanchez, A.

    2004-01-01

    Although the fraction of radionuclides linked to soil organic matter and soil microorganisms may be relatively small when compared to the amount bound to the mineral constituents, (mostly irreversibly bound), this fraction is of great importance as it remains readily exchangeable and is thus available for plant uptake. Many studies have measured the uptake of radionuclides by organic soils but the role of soil micro-organisms may have been masked by the presence of even small amounts of clay minerals occurring in these soils. We have carried out a series of experiments using a biologically active, 'mineral-free' organic soil produced under laboratory conditions, to determine the potential of soil micro-organisms to accumulate radionuclides Cs-134 and Sr-85. Biological uptake and release was differentiated from abiotic processes by comparing experimental results with inoculated and non-inoculated sterile organic material. We have investigated the role of different clay minerals, competing potassium and calcium ions, and changes in temperature on the sorption of Cs and Sr isotopes. The results from studies so far show conclusively that living components of soil systems are of primary importance in the uptake of radionuclides in organic material, microorganisms also influence the importance of chemical factors (e.g. adsorption to clay minerals) which may play a secondary role in these highly organic systems. In further experiments we hope to define the precise role of specific soil micro-organisms in these organic systems. (author)

  2. Methylamine as a nitrogen source for microorganisms from a coastal marine environment.

    Science.gov (United States)

    Taubert, Martin; Grob, Carolina; Howat, Alexandra M; Burns, Oliver J; Pratscher, Jennifer; Jehmlich, Nico; von Bergen, Martin; Richnow, Hans H; Chen, Yin; Murrell, J Colin

    2017-06-01

    Nitrogen is a key limiting resource for biomass production in the marine environment. Methylated amines, released from the degradation of osmolytes, could provide a nitrogen source for marine microbes. Thus far, studies in aquatic habitats on the utilization of methylamine, the simplest methylated amine, have mainly focussed on the fate of the carbon from this compound. Various groups of methylotrophs, microorganisms that can grow on one-carbon compounds, use methylamine as a carbon source. Non-methylotrophic microorganisms may also utilize methylamine as a nitrogen source, but little is known about their diversity, especially in the marine environment. In this proof-of-concept study, stable isotope probing (SIP) was used to identify microorganisms from a coastal environment that assimilate nitrogen from methylamine. SIP experiments using 15 N methylamine combined with metagenomics and metaproteomics facilitated identification of active methylamine-utilizing Alpha- and Gammaproteobacteria. The draft genomes of two methylamine utilizers were obtained and their metabolism with respect to methylamine was examined. Both bacteria identified in these SIP experiments used the γ-glutamyl-methylamide pathway, found in both methylotrophs and non-methylotrophs, to metabolize methylamine. The utilization of 15 N methylamine also led to the release of 15 N ammonium that was used as nitrogen source by other microorganisms not directly using methylamine. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  3. Peptidomic analysis reveals proteolytic activity of kefir microorganisms on bovine milk proteins

    Science.gov (United States)

    Dallas, David C.; Citerne, Florine; Tian, Tian; Silva, Vitor L. M.; Kalanetra, Karen M.; Frese, Steven A.; Robinson, Randall C.; Mills, David A.; Barile, Daniela

    2015-01-01

    Scope The microorganisms that make up kefir grains are well known for lactose fermentation, but the extent to which they hydrolyze and consume milk proteins remains poorly understood. Peptidomics technologies were used to examine the proteolytic activity of kefir grains on bovine milk proteins. Methods and results Gel electrophoresis revealed substantial digestion of milk proteins by kefir grains, with mass spectrometric analysis showing the release of 609 protein fragments and alteration of the abundance of >1,500 peptides that derived from 27 milk proteins. Kefir contained 25 peptides identified from the literature as having biological activity, including those with antihypertensive, antimicrobial, immunomodulatory, opioid and anti-oxidative functions. 16S rRNA and shotgun metagenomic sequencing identified the principle taxa in the culture as Lactobacillus species. Conclusion The model kefir sample contained thousands of protein fragments released in part by kefir microorganisms and in part by native milk proteases. PMID:26616950

  4. Peptidomic analysis reveals proteolytic activity of kefir microorganisms on bovine milk proteins.

    Science.gov (United States)

    Dallas, David C; Citerne, Florine; Tian, Tian; Silva, Vitor L M; Kalanetra, Karen M; Frese, Steven A; Robinson, Randall C; Mills, David A; Barile, Daniela

    2016-04-15

    The microorganisms that make up kefir grains are well known for lactose fermentation, but the extent to which they hydrolyze and consume milk proteins remains poorly understood. Peptidomics technologies were used to examine the proteolytic activity of kefir grains on bovine milk proteins. Gel electrophoresis revealed substantial digestion of milk proteins by kefir grains, with mass spectrometric analysis showing the release of 609 protein fragments and alteration of the abundance of >1500 peptides that derived from 27 milk proteins. Kefir contained 25 peptides identified from the literature as having biological activity, including those with antihypertensive, antimicrobial, immunomodulatory, opioid and anti-oxidative functions. 16S rRNA and shotgun metagenomic sequencing identified the principle taxa in the culture as Lactobacillus species. The model kefir sample contained thousands of protein fragments released in part by kefir microorganisms and in part by native milk proteases. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Optimal Zn-Modified Ca–Si-Based Ceramic Nanocoating with Zn Ion Release for Osteoblast Promotion and Osteoclast Inhibition in Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Jiangming Yu

    2017-01-01

    Full Text Available We investigated the slow release of Zn ion (Zn2+ from nanocoatings and compared the in vitro response of osteoblasts (MC3T3-E1 and proosteoclasts (RAW 264.7 cultured on Ca2ZnSi2O7 nanocoated with different Zn/Ca molar ratios on a Ti-6Al-4V (i.e., Ti substrate to optimize cell behaviors and molecule levels. Significant morphology differences were observed among samples. By comparing with pure Ti and CaSiO3 nanocoating, the morphology of Ca2ZnSi2O7 ceramic nanocoatings was rough and contained small nanoparticles or aggregations. Slow Zn2+ release from nanocoatings was observed and Zn2+ concentration was regulated by varying the Zn/Ca ratios. The cell-response results showed Ca2ZnSi2O7 nanocoating at different Zn/Ca molar ratios for osteoblasts and osteoclasts. Compared to other nanocoatings and Ti, sample Zn/Ca (0.3 showed the highest cell viability and upregulated expression of the osteogenic differentiation genes ALP, COL-1, and OCN. Additionally, sample Zn/Ca (0.3 showed the greatest inhibition of RAW 264.7 cell growth and decreased the mRNA levels of osteoclast-related genes OAR, TRAP, and HYA1. Therefore, the optimal Zn-Ca ratio of 0.3 in Ca2ZnSi2O7 ceramic nanocoating on Ti had a dual osteoblast-promoting and osteoclast-inhibiting effect to dynamically balance osteoblasts/osteoclasts. These optimal Zn-Ca ratios are valuable for Ca2ZnSi2O7 ceramic nanocoating on Ti-coated implants for potential applications in bone tissue regeneration.

  6. Identification of Microorganisms by Modern Analytical Techniques.

    Science.gov (United States)

    Buszewski, Bogusław; Rogowska, Agnieszka; Pomastowski, Paweł; Złoch, Michał; Railean-Plugaru, Viorica

    2017-11-01

    Rapid detection and identification of microorganisms is a challenging and important aspect in a wide range of fields, from medical to industrial, affecting human lives. Unfortunately, classical methods of microorganism identification are based on time-consuming and labor-intensive approaches. Screening techniques require the rapid and cheap grouping of bacterial isolates; however, modern bioanalytics demand comprehensive bacterial studies at a molecular level. Modern approaches for the rapid identification of bacteria use molecular techniques, such as 16S ribosomal RNA gene sequencing based on polymerase chain reaction or electromigration, especially capillary zone electrophoresis and capillary isoelectric focusing. However, there are still several challenges with the analysis of microbial complexes using electromigration technology, such as uncontrolled aggregation and/or adhesion to the capillary surface. Thus, an approach using capillary electrophoresis of microbial aggregates with UV and matrix-assisted laser desorption ionization time-of-flight MS detection is presented.

  7. Assessment of microorganisms from Indonesian Oil Fields

    Energy Technology Data Exchange (ETDEWEB)

    Kadarwati, S.; Udiharto, M.; Rahman, M.; Jasjfi, E.; Legowo, E.H. [Research and Development Centre for Oil and Gas Technology LEMIGAS, Jakarta Selatan (Indonesia)

    1995-12-31

    Petroleum resources have been the mainstay of the national development in Indonesia. However, resources are being depleted after over a century of exploitation, while the demand continues to grow with the rapid economic development of the country. In facing the problem, EOR has been applied in Indonesia, such as the steamflooding project in Duri field, but a more energy efficient technology would be preferable. Therefore, MEOR has been recommended as a promising solution. Our study, aimed at finding indigenous microorganisms which can be developed for application in MEOR, has isolated microbes from some oil fields of Indonesia. These microorganisms have been identified, their activities studied, and the effects of their metabolisms examined. This paper describes the research carried out by LEMIGAS in this respect, giving details on the methods of sampling, incubation, identification, and activation of the microbes as well as tests on the effects of their metabolites, with particular attention to those with potential for application in MEOR.

  8. UV inactivation of pathogenic and indicator microorganisms

    International Nuclear Information System (INIS)

    Chang, J.C.; Ossoff, S.F.; Lobe, D.C.; Dorfman, M.H.; Dumais, C.M.; Qualls, R.G.; Johnson, J.D.

    1985-01-01

    Survival was measured as a function of the dose of germicidal UV light for the bacteria Escherichia coli, Salmonella typhi, Shigella sonnei, Streptococcus faecalis, Staphylococcus aureus, and Bacillus subtilis spores, the enteric viruses poliovirus type 1 and simian rotavirus SA11, the cysts of the protozoan Acanthamoeba castellanii, as well as for total coliforms and standard plate count microorganisms from secondary effluent. The doses of UV light necessary for a 99.9% inactivation of the cultured vegetative bacteria, total coliforms, and standard plate count microorganisms were comparable. However, the viruses, the bacterial spores, and the amoebic cysts required about 3 to 4 times, 9 times, and 15 times, respectively, the dose required for E. coli. These ratios covered a narrower relative dose range than that previously reported for chlorine disinfection of E. coli, viruses, spores, and cysts

  9. UV inactivation of pathogenic and indicator microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Chang, J.C.; Ossoff, S.F.; Lobe, D.C.; Dorfman, M.H.; Dumais, C.M.; Qualls, R.G.; Johnson, J.D.

    1985-06-01

    Survival was measured as a function of the dose of germicidal UV light for the bacteria Escherichia coli, Salmonella typhi, Shigella sonnei, Streptococcus faecalis, Staphylococcus aureus, and Bacillus subtilis spores, the enteric viruses poliovirus type 1 and simian rotavirus SA11, the cysts of the protozoan Acanthamoeba castellanii, as well as for total coliforms and standard plate count microorganisms from secondary effluent. The doses of UV light necessary for a 99.9% inactivation of the cultured vegetative bacteria, total coliforms, and standard plate count microorganisms were comparable. However, the viruses, the bacterial spores, and the amoebic cysts required about 3 to 4 times, 9 times, and 15 times, respectively, the dose required for E. coli. These ratios covered a narrower relative dose range than that previously reported for chlorine disinfection of E. coli, viruses, spores, and cysts.

  10. Influence of near ultraviolet light on microorganisms

    International Nuclear Information System (INIS)

    Fraikin, G.Y.A.; Rubin, L.B.

    1980-01-01

    Our results and the recent literature data on the biological action of near ultraviolet light (300-380 nm) are examined in the review. Factual material is presented on the principles governing the manifestation of the following effects of near ultraviolet light in microorganisms: inactivation, delayed growth, photoreactivation, photoprotection, photoinduced sporulation (in fungi), and carotene synthesis. The mature and possible mechanisms of the effects examined are discussed

  11. Chemosensing in microorganisms to practical biosensors

    OpenAIRE

    Ghosh, Surya K.; Kundu, Tapanendu; Sain, Anirban

    2012-01-01

    Microorganisms like bacteria can sense concentration of chemo-attractants in its medium very accurately. They achieve this through interaction between the receptors on their cell surface and the chemo-attractant molecules (like sugar). But the physical processes like diffusion set some limits on the accuracy of detection which was discussed by Berg and Purcell in the late seventies. We have a re-look at their work in order to assess what insight it may offer towards making efficient, practica...

  12. Bioemulsan Production by Iranian Oil Reservoirs Microorganisms

    Directory of Open Access Journals (Sweden)

    A Amiriyan, M Mazaheri Assadi, VA Saggadian, A Noohi

    2004-10-01

    Full Text Available The biosurfactants are believed to be surface active components that are shed into the surrounding medium during the growth of the microorganisms. The oil degrading microorganism Acinetobacter calcoaceticus RAG-1 produces a poly-anionic biosurfactant, hetero-polysaccharide bioemulsifier termed as emulsan which forms and stabilizes oil-water emulsions with a variety of hydrophobic substrates. In the present paper results of the possibility of biosurfactant (Emulsan production by microorganisms isolated from Iranian oil reservoirs is presented. Fourthy three gram negative and gram positive, non fermentative, rod bacilli and coccobacilli shaped baceria were isolated from the oil wells of Bibi Hakimeh, Siri, Maroon, Ilam , East Paydar and West Paydar. Out of the isolated strains, 39 bacterial strains showed beta haemolytic activity, further screening revealed the emulsifying activity and surface tension. 11 out of 43 tested emulsifiers were identified as possible biosurfactant producers and two isolates produced large surface tension reduction, indicating the high probability of biosurfactant production. Further investigation revealed that, two gram negative, oxidase negative, aerobic and coccoid rods isolates were the best producers and hence designated as IL-1, PAY-4. Whole culture broth of isolates reduced surface tension from 68 mN /m to 30 and 29.1mN/m, respectively, and were stable during exposure to high salinity (10%NaCl and elevated temperatures(120C for 15 min .

  13. [Succession of chitinolytic microorganisms in chernozem soil].

    Science.gov (United States)

    Manucharova, N A; Belova, E V; Vorob'ev, A V; Polianskaia, L M; Stepanov, A L

    2005-01-01

    The chitinolytic prokaryotic and eukaryotic microbial complex of chernozem soil has been investigated in the course of a succession initiated by the introduction of chitin and humidification. The dynamics of the cell numbers of chitinolytic microorganisms and of their biomass was assessed by fluorescent microscopy and by inoculation of selective media. Emission of carbon dioxide and nitrous oxide, as well as dinitrogen fixation, was assessed by gas chromatography. It was found that, when the succession was initiated by the introduction of both chitin and humidification, it resulted in greater cell numbers and biomass of chitinolytic microorganisms and higher levels of CO2 and N2O emission and of nitrogen fixation than when the succession was initiated by humidification alone. As compared to the control samples, a significant (twofold) increase in the prokaryote cell number and biomass was found on the fourth day of the succession initiated by humidification and introduction of chitin. One week after the initiation of succession, the fungal biomass and length of mycelium were twice as high as those in the control samples. These results led to the conclusion that chitin utilization in chernozem soil starts during the initial stages of succession and is performed by both prokaryotic and eukaryotic microorganisms.

  14. Monitoring of psychrotrophic microorganisms in raw milk

    Directory of Open Access Journals (Sweden)

    Radka Burdychová

    2008-01-01

    Full Text Available The group of psychrotrophic microorganisms belongs to the microorganisms representing a risk for human health as well as a risk of milk and milk products spoilage. Some genus are considered to be significant producers of proteolytic and lipolytic enzymes. In this work, we analysed raw milk samples (n = 109 originated from 26 different suppliers from the area of North and Middle Moravia. The screening was performed from March 2007 to February 2008. The total bacterial counts (TBC ranged between 3.2 × 103 to 8.3 × 106 CFU/ml. The psychrotrophic bacterial counts (PBC ranged between 1.0 × 103 to 8.2 × 106 CFU/ml. Total of 48.62 % and 48.62 % of samples exceeded the hygienic limit in raw milk for TBC and PBC, respectively. The correlation between TBC and PBC was highly significant (r = 0.87.Significantly higher (P < 0.05 numbers of psychrotrophic microorganisms were detected in summer months. The identification of isolates was carried out and all strains were sreened for ability to produce proteolytic and lipolytic enzymes. The most commonly identified genus in raw milk was of the genus Pseudomonas. The ability to produce proteases or lipases was found at 76 % identified bacterial strains.

  15. Selection of mesophilic microorganisms with biodesulfuration capacity

    International Nuclear Information System (INIS)

    Madero, A; Mogollon, L. I; Mora, A.L; Osorio, L.F

    1998-01-01

    The development of bio desulfurization (BDS) processes for hydrocarbons requires fast and reliable methods for the screening of microorganisms. This work shows the results of the screening process for indigenous Colombian strains with a BDS potential capacity. The main criteria for the screening were the qualitative and quantitative determination of 2-hydroxybiphenyl (2-HBP) as the typical metabolite of the 4S specific pathway. Microorganisms were cultured by two methodologies, A and B, using DBT as the model compound. The quantitative determination of metabolites was made by HPLC. Thirteen strains were evaluated, including the strain Rhodococcus rhodocrous IGTS8, by methods A and B. In method A, the inoculum was exposed to DBT since the beginning of the culture. Method B, employed two stages: (i) Growth period under limiting sulfur conditions, (ii) Transforming period, in which the pre-grown inoculum was exposed to the organic sulfur substrate. The culture of mesophilic microorganisms isolated by method B, served to find a mechanism for the organic sulfur metabolism, and the evaluation of the sulfur removal capability of five indigenous strains. In the cultures of these strains, 2- hydroxybiphenyl (2-HBP) was detected as a byproduct of DBT metabolism, both qualitatively and quantitatively

  16. Magnetotaxy in microorganisms of Rio de Janeiro region: an overview

    International Nuclear Information System (INIS)

    Barros, H.G. de P.L. de; Esquivel, D.M.S.

    1983-01-01

    Some characteristics of several magnetotactic microorganisms found in sediments collected in Rio de Janeiro region are presented. The study of magnetic characteristics of these microorganisms indicate some general properties of the magnetotaxy phenomenons. (L.C.) [pt

  17. Deciphering the Role of Phytoalexins in Plant-Microorganism Interactions and Human Health

    Directory of Open Access Journals (Sweden)

    Philippe Jeandet

    2014-11-01

    Full Text Available Phytoalexins are low molecular weight antimicrobial compounds that are produced by plants as a response to biotic and abiotic stresses. As such they take part in an intricate defense system which enables plants to control invading microorganisms. In this review we present the key features of this diverse group of molecules, namely their chemical structures, biosynthesis, regulatory mechanisms, biological activities, metabolism and molecular engineering.

  18. Biogas Production and Engine Conversion From Diesel Engine to Biogas Engine for Lighting in Rural Area

    OpenAIRE

    Tun, Seint Thandar

    2012-01-01

    The research of alternative fuels implemented in internal combustion engines are becoming the subjects of interest nowadays. This paper describes a production of biogas from cow dung, diesel engine conversion process with piston modification of ZH1115 diesel engine. To produce biogas, the usual practice is to mix water with some organic material, such as cow dung (a free source of the appropriate micro-organisms). The slurry is placed in a leak-proof container (called a digester) and leaves i...

  19. Rewriting the Metabolic Blueprint: Advances in Pathway Diversification in Microorganisms

    Directory of Open Access Journals (Sweden)

    Gazi Sakir Hossain

    2018-02-01

    Full Text Available Living organisms have evolved over millions of years to fine tune their metabolism to create efficient pathways for producing metabolites necessary for their survival. Advancement in the field of synthetic biology has enabled the exploitation of these metabolic pathways for the production of desired compounds by creating microbial cell factories through metabolic engineering, thus providing sustainable routes to obtain value-added chemicals. Following the past success in metabolic engineering, there is increasing interest in diversifying natural metabolic pathways to construct non-natural biosynthesis routes, thereby creating possibilities for producing novel valuable compounds that are non-natural or without elucidated biosynthesis pathways. Thus, the range of chemicals that can be produced by biological systems can be expanded to meet the demands of industries for compounds such as plastic precursors and new antibiotics, most of which can only be obtained through chemical synthesis currently. Herein, we review and discuss novel strategies that have been developed to rewrite natural metabolic blueprints in a bid to broaden the chemical repertoire achievable in microorganisms. This review aims to provide insights on recent approaches taken to open new avenues for achieving biochemical production that are beyond currently available inventions.

  20. Rewriting the Metabolic Blueprint: Advances in Pathway Diversification in Microorganisms.

    Science.gov (United States)

    Hossain, Gazi Sakir; Nadarajan, Saravanan Prabhu; Zhang, Lei; Ng, Tee-Kheang; Foo, Jee Loon; Ling, Hua; Choi, Won Jae; Chang, Matthew Wook

    2018-01-01

    Living organisms have evolved over millions of years to fine tune their metabolism to create efficient pathways for producing metabolites necessary for their survival. Advancement in the field of synthetic biology has enabled the exploitation of these metabolic pathways for the production of desired compounds by creating microbial cell factories through metabolic engineering, thus providing sustainable routes to obtain value-added chemicals. Following the past success in metabolic engineering, there is increasing interest in diversifying natural metabolic pathways to construct non-natural biosynthesis routes, thereby creating possibilities for producing novel valuable compounds that are non-natural or without elucidated biosynthesis pathways. Thus, the range of chemicals that can be produced by biological systems can be expanded to meet the demands of industries for compounds such as plastic precursors and new antibiotics, most of which can only be obtained through chemical synthesis currently. Herein, we review and discuss novel strategies that have been developed to rewrite natural metabolic blueprints in a bid to broaden the chemical repertoire achievable in microorganisms. This review aims to provide insights on recent approaches taken to open new avenues for achieving biochemical production that are beyond currently available inventions.

  1. Release plan for Big Pete

    International Nuclear Information System (INIS)

    Edwards, T.A.

    1996-11-01

    This release plan is to provide instructions for the Radiological Control Technician (RCT) to conduct surveys for the unconditional release of ''Big Pete,'' which was used in the removal of ''Spacers'' from the N-Reactor. Prior to performing surveys on the rear end portion of ''Big Pete,'' it shall be cleaned (i.e., free of oil, grease, caked soil, heavy dust). If no contamination is found, the vehicle may be released with the permission of the area RCT Supervisor. If contamination is found by any of the surveys, contact the cognizant Radiological Engineer for decontamination instructions

  2. The fate of organic compounds in a cement-based repository: impact on the engineered barrier and the release of C-14 from the near field

    International Nuclear Information System (INIS)

    Wieland, E.; Rothardt, J.; Schlotterbeck, G.

    2015-01-01

    The degradation of organic materials is taken into account in the safety analysis for a L/ILW (Low- and intermediate-level radioactive waste) repository in Switzerland with the aim of assessing possible impacts on the cement barrier. The waste forms to be disposed of in the planned L/ILW repository will contain HMW polymers and LMW monomeric organic materials. It is anticipated that these organic materials have different degradation rates and therefore different life times in a repository. While the decomposition of LMW organics is expected to be fast and complete during the oxic and early anoxic states of a repository, i.e. before and shortly after repository closure, the decomposition of the HMW polymeric materials is expected to be very slow and, for some materials, to occur over the entire life time of the repository. The degradation of organic materials generates CO 2 which gives rise to carbonation of the cement barrier. The maximum acceptable loading of organics in the near field with no detrimental effect on radionuclide immobilization can be estimated on the assumption that at maximum 2/3 of the total portlandite inventory of hydrated cement is allowed to convert to CaCO 3 in the case of waste compartments for which the cementitious barrier should remain intact. The maximum loading is determined by the inventory of the organic material under consideration as well as the carbon content and the oxidation state of carbon of the material. Carbon-14 bound in organic compounds is considered to be an important contributor to the annual dose released from a L/ILW repository. While the 14 C inventory is well known, the chemical speciation of 14 C in the cementitious near field upon liberation in the course of the corrosion of activated steel is only poorly understood. Preliminary corrosion tests with non-activated steel powders show the formation of gaseous and dissolved organic carbon species, e.g. alkanes/alkenes, alcohols, aldehydes, and carboxylic acids

  3. Microorganisms and methods for producing pyruvate, ethanol, and other compounds

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Jennifer L.; Zhang, Xiaolin

    2017-12-26

    Microorganisms comprising modifications for producing pyruvate, ethanol, and other compounds. The microorganisms comprise modifications that reduce or ablate activity of one or more of pyruvate dehydrogenase, 2-oxoglutarate dehydrogenase, phosphate acetyltransferase, acetate kinase, pyruvate oxidase, lactate dehydrogenase, cytochrome terminal oxidase, succinate dehydrogenase, 6-phosphogluconate dehydrogenase, glutamate dehydrogenase, pyruvate formate lyase, pyruvate formate lyase activating enzyme, and isocitrate lyase. The microorganisms optionally comprise modifications that enhance expression or activity of pyruvate decarboxylase and alcohol dehydrogenase. The microorganisms are optionally evolved in defined media to enhance specific production of one or more compounds. Methods of producing compounds with the microorganisms are provided.

  4. Extracellular electron transfer mechanisms between microorganisms and minerals

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Liang; Dong, Hailiang; Reguera, Gemma; Beyenal, Haluk; Lu, Anhuai; Liu, Juan; Yu, Han-Qing; Fredrickson, James K.

    2016-08-30

    Electrons can be transferred from microorganisms to multivalent metal ions that are associated with minerals and vice versa. As the microbial cell envelope is neither physically permeable to minerals nor electrically conductive, microorganisms have evolved strategies to exchange electrons with extracellular minerals. In this Review, we discuss the molecular mechanisms that underlie the ability of microorganisms to exchange electrons, such as c-type cytochromes and microbial nanowires, with extracellular minerals and with microorganisms of the same or different species. Microorganisms that have extracellular electron transfer capability can be used for biotechnological applications, including bioremediation, biomining and the production of biofuels and nanomaterials.

  5. Screening of biosurfactants from cloud microorganisms

    Science.gov (United States)

    Sancelme, Martine; Canet, Isabelle; Traikia, Mounir; Uhliarikova, Yveta; Capek, Peter; Matulova, Maria; Delort, Anne-Marie; Amato, Pierre

    2015-04-01

    The formation of cloud droplets from aerosol particles in the atmosphere is still not well understood and a main source of uncertainties in the climate budget today. One of the principal parameters in these processes is the surface tension of atmospheric particles, which can be strongly affected by trace compounds called surfactants. Within a project devoted to bring information on atmospheric surfactants and their effects on cloud droplet formation, we focused on surfactants produced by microorganisms present in atmospheric waters. From our unique collection of microorganisms, isolated from cloud water collected at the Puy-de-Dôme (France),1 we undertook a screening of this bank for biosurfactant producers. After extraction of the supernatants of the pure cultures, surface tension of crude extracts was determined by the hanging drop technique. Results showed that a wide variety of microorganisms are able to produce biosurfactants, some of them exhibiting strong surfactant properties as the resulting tension surface decreases to values less then 35 mN.m-1. Preliminary analytical characterization of biosurfactants, obtained after isolation from overproducing cultures of Rhodococcus sp. and Pseudomonas sp., allowed us to identify them as belonging to two main classes, namely glycolipids and glycopeptides. 1. Vaïtilingom, M.; Attard, E.; Gaiani, N.; Sancelme, M.; Deguillaume, L.; Flossmann, A. I.; Amato, P.; Delort, A. M. Long-term features of cloud microbiology at the puy de Dôme (France). Atmos. Environ. 2012, 56, 88-100. Acknowledgements: This work is supported by the French-USA ANR SONATA program and the French-Slovakia programs Stefanik and CNRS exchange.

  6. High-efficiency extracellular release of free fatty acids from Aspergillus oryzae using non-ionic surfactants.

    Science.gov (United States)

    Tamano, Koichi; Miura, Ai; Koike, Hideaki; Kamisaka, Yasushi; Umemura, Myco; Machida, Masayuki

    2017-04-20

    Free fatty acids (FFAs) are useful for generating biofuel compounds and functional lipids. Microbes are increasingly exploited to produce FFAs via metabolic engineering. However, in many microorganisms, FFAs accumulate in the cytosol, and disrupting cells to extract them is energy intensive. Thus, a simple cost-effective extraction technique must be developed to remove this drawback. We found that FFAs were released from cells of the filamentous fungus Aspergillus oryzae with high efficiency when they were cultured or incubated with non-ionic surfactants such as Triton X-100. The surfactants did not reduce hyphal growth, even at 5% (w/v). When the faaA disruptant was cultured with 1% Triton X-100, more than 80% of the FFAs synthesized de novo were released. When the disruptant cells grown without surfactants were incubated for 1h in 1% Triton X-100 solution, more than 50% of the FFAs synthesized de novo were also released. Other non-ionic surfactants in the same ether series, such as Brij 58, IGEPAL CA-630, and Tergitol NP-40, elicited a similar FFA release. The dry cell weight of total hyphae decreased when grown with 1% Triton X-100. The decrement was 4.9-fold greater than the weight of the released FFAs, implying release of other intracellular compounds. Analysis of the culture supernatant showed that intracellular lactate dehydrogenase was also released, suggesting that FFAs are not released by a specific transporter. Therefore, ether-type non-ionic surfactants probably cause non-specific release of FFAs and other intracellular compounds by increasing cell membrane permeability. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Impact of microorganism on polonium volatilization

    International Nuclear Information System (INIS)

    Momoshima, N.; Ishida, A.; Fukuda, A.; Yoshinaga, C.

    2007-01-01

    Volatilization of polonium by microorganisms, Chromobacterium violaceum, Escherichia coli and Bacillus subtilis was examined for pure cultures in LB medium at 30 deg C, showing relative Po emission intensity 100, 10 and 1, respectively. Chromobacterium violaceum pre-cultured in LB medium without Po and suspended in water with Po showed high Po volatilization in spite of poor nutriment condition. Antibiotics inhibit volatilization of Po and cultivation at low temperature greatly reduced volatilization. The results strongly support the biological effects on Po volatilization. (author)

  8. Microorganisms in human milk: lights and shadows.

    Science.gov (United States)

    Civardi, Elisa; Garofoli, Francesca; Tzialla, Chryssoula; Paolillo, Piermichele; Bollani, Lina; Stronati, Mauro

    2013-10-01

    Human milk has been traditionally considered germ free, however, recent studies have shown that it represents a continuous supply of commensal and potentially probiotic bacteria to the infant gut. Mammary microbioma may exercise anti-infective, anti-inflammatory, immunomodulatory and metabolic properties. Moreover human milk may be a source of pathogenic microorganism during maternal infection, if contaminated during expression or in case of vaccination of the mother. The non-sterility of breast milk can, thus, be seen as a protective factor, or rarely, as a risk factor for the newborn.

  9. Microbial biogeography: putting microorganisms on the map.

    Science.gov (United States)

    Martiny, Jennifer B Hughes; Bohannan, Brendan J M; Brown, James H; Colwell, Robert K; Fuhrman, Jed A; Green, Jessica L; Horner-Devine, M Claire; Kane, Matthew; Krumins, Jennifer Adams; Kuske, Cheryl R; Morin, Peter J; Naeem, Shahid; Ovreås, Lise; Reysenbach, Anna-Louise; Smith, Val H; Staley, James T

    2006-02-01

    We review the biogeography of microorganisms in light of the biogeography of macroorganisms. A large body of research supports the idea that free-living microbial taxa exhibit biogeographic patterns. Current evidence confirms that, as proposed by the Baas-Becking hypothesis, 'the environment selects' and is, in part, responsible for spatial variation in microbial diversity. However, recent studies also dispute the idea that 'everything is everywhere'. We also consider how the processes that generate and maintain biogeographic patterns in macroorganisms could operate in the microbial world.

  10. Microorganisms and biomolecules in space hard environment

    Science.gov (United States)

    Horneck, G.

    1981-01-01

    Microorganisms and biomolecules exposed to space vacuum and to different intensities of selected wavelengths of solar ultraviolet radiation is studied. The influence of these factors, applied singly or simultaneously, on the integrity of microbial systems and biomolecules is measured. Specifically, this experiment will study in Bacillus subtilis spores (1) disturbances in subsequent germination, outgrowth, and colony formation; (2) photochemical reactions of the DNA and protein in vivo and in vitro and their role in biological injury; and (3) the efficiency of repair processes in these events.

  11. Microorganisms as Indicators of Soil Health

    DEFF Research Database (Denmark)

    Nielsen, M. N.; Winding, A.; Binnerup, S.

    ecosystem parameters representing policy relevant end points. It is further recommended to identify a specific minimum data set for specific policy relevant end points, to carefully establish baseline values, to improve scientific knowledge on biodiversity and modelling of soil data, and to implement new......Microorganisms are an essential part of living soil and of outmost importance for soil health. As such they can be used as indicators of soil health. This report reviews the current and potential future use of microbial indicators of soil health and recommends specific microbial indicators for soil...... indicators into soil monitoring programmes as they become applicable....

  12. Effects of phosphate-solubilizing bacteria, native microorganisms, and rock dust on Jatropha curcas L. growth.

    Science.gov (United States)

    Santana, E B; Marques, E L S; Dias, J C T

    2016-10-05

    Microorganisms with the ability to release nutrients to the soil from insoluble sources may be useful for plant cultivation. We evaluated the growth-promoting effect on Jatropha curcas L. of phosphate-solubilizing bacteria (PSB) and the native microbiota in soil with or without rock dust. J. curcas L. is important for biodiesel production. The experiments were performed in a greenhouse under a random-statistical design with 14 replicates. The soil received increasing dosages of rock dust. The presence of resident microorganisms and PSB inoculum was correlated with plant height, biomass production, and phosphorus content in plants for 120 days. Native soil microorganisms were detected and identified using denaturing gradient gel electrophoresis and DNA sequence analysis. Several bacterial populations belonged to the genus Bacillus. Populations associated with the phyla Chytridiomycota and Ascomycota were detected among the fungi. The best results for the variable plant height were correlated with the presence of resident microbiota and rock dust until the end of the experiment. The largest biomass production and the highest content of phosphorus occurred in the presence of soil-resident microbiota only up to 120 days. No significant effects were observed for biomass production with the use of PSB combined with rock dust. J. curcas L. under the influence of only resident microbiota showed the best plant growth results. Future research will focus on the specificity of resident microbiota activity in plant growth promotion and the isolation of these microorganisms to produce a new inoculum to be tested in various plants.

  13. Methane release

    International Nuclear Information System (INIS)

    Seifert, M.

    1999-01-01

    The Swiss Gas Industry has carried out a systematic, technical estimate of methane release from the complete supply chain from production to consumption for the years 1992/1993. The result of this survey provided a conservative value, amounting to 0.9% of the Swiss domestic output. A continuation of the study taking into account new findings with regard to emission factors and the effect of the climate is now available, which provides a value of 0.8% for the target year of 1996. These results show that the renovation of the network has brought about lower losses in the local gas supplies, particularly for the grey cast iron pipelines. (author)

  14. The Characterization of Psychrophilic Microorganisms and their potentially useful Cold-Active Glycosidases Final Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Brenchly, Jean E.

    2008-06-30

    Our studies of novel, cold-loving microorganisms have focused on two distinct extreme environments. The first is an ice core sample from a 120,000 year old Greenland glacier. The results of this study are particularly exciting and have been highlighted with press releases and additional coverage. The first press release in 2004 was based on our presentation at the General Meeting of the American Society for Microbiology and was augmented by coverage of our publication (Appl. Environ. Microbiol. 2005. Vol. 71:7806) in the Current Topics section of the ASM news journal, “Microbe.” Of special interest for this report was the isolation of numerous, phylogenetically distinct and potentially novel ultrasmall microorganisms. The detection and isolation of members of the ultrasmall population is significant because these cells pass through 0.2 micron pore filters that are generally used to trap microorganisms from environmental samples. Thus, analyses by other investigators that examined only cells captured on the filters would have missed a significant portion of this population. Only a few ultrasmall isolates had been obtained prior to our examination of the ice core samples. Our development of a filtration enrichment and subsequent cultivation of these organisms has added extensively to the collection of, and knowledge about, this important population in the microbial world.

  15. Microorganisms as bioindicators of pollutants in soil

    Directory of Open Access Journals (Sweden)

    Milošević Nada

    2010-01-01

    Full Text Available Microorganisms are the predominant portion of the soil's biological phase and they are indicators of soil health and quality. Soil microorganisms a take part in degradation of organic and inorganic compounds, b their activity, number and diversity may serve as bioindicators of toxic effects on soil biological activity, c some microbial species may be used for soil bioremediation and d some sensitive microbes are used in eco-toxicity tests. The primary microbial population starts to decompose herbicides several days after their arrival into the soil. The secondary population produces induced enzymes and decomposes herbicides after a period of adaptation. Certain microbial groups are indifferent to the applied herbicides. Effect of heavy metals on soil microbial activity depends on the element, their concentration, microbial species, as well as physical and chemical soil properties. Toxic level of individual pollutants depends on their origin and composition. However, combined application of chemicals makes room for the occurrence of synergistic toxic effects detrimental for the ecosystem and human health. .

  16. Identification of periodontopathogen microorganisms by PCR technique

    Directory of Open Access Journals (Sweden)

    Milićević Radovan

    2008-01-01

    Full Text Available INTRODUCTION Periodontitis is an inflammatory disease of the supporting tissues of teeth and is a major cause of tooth loss in adults. The onset and progression of periodontal disease is attributed to the presence of elevated levels of a consortium of pathogenic bacteria. Gram negative bacteria, mainly strict anaerobes, play the major role. OBJECTIVE The present study aimed to assess the presence of the main types of microorganisms involved in the aetiopathogenesis of periodontal disease: Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Eikenella corrodens, Treponema denticola, Tanerella forsythia and Prevotella intermedia in different samples collected from the oral cavity of 90 patients diagnosed with periodontitis. METHOD Bacterial DNA detection was performed in diverse biological materials, namely in dental plaque, gingival tissue and saliva, by means of multiplex PCR, a technique that allows simultaneous identification of two different bacterial genomes. RESULTS In the dental plaque of the periodontitis patients, Treponema denticola dominated. In the gingival tissue, Tannerella forsythia and Treponema denticola were the microbiota most frequently detected, whilst in saliva Treponema denticola and Eikenella corrodens were found with the highest percentage. CONCLUSION The identification of microorganisms by multiplex PCR is specific and sensitive. Rapid and precise assessment of different types of periodontopathogens is extremely important for early detection of the infection and consequently for the prevention and treatment of periodontal disease. In everyday clinical practice, for routine bacterial evaluation in patients with periodontal disease, the dental plaque is the most suitable biological material, because it is the richest in periodontal bacteria.

  17. Sterilization of Microorganisms by Ozone and Ultrasound

    Science.gov (United States)

    Krasnyj, V. V.; Klosovskij, A. V.; Panasko, T. A.; Shvets, O. M.; Semenova, O. T.; Taran, V. S.; Tereshin, V. I.

    2008-03-01

    The results of recent experimental methods of sterilization of microorganisms with the use of ozone and ultrasound are presented. The main aim was to optimize the process of sterilization in water solution taking into account the ozone concentration, the power of ultrasonic emitter and the temperature of water. In the present work, the ultrasonic cavitation with simultaneous ozone generation has been used. The high ozone concentration in water solution was achieved by two-barrier glow discharge generated at atmospheric pressure and a cooling thermo-electric module. Such a sterilizer consists of ozone generator in a shape of flat electrodes covered with dielectric material and a high-voltage pulsed power supply of 250 W. The sterilization camera was equipped with ultrasonic source operated at 100 W. The experiments on the inactivation of bacteria of the Bacillus Cereus type were carried out in the distilled water saturated by ozone. The ozone concentration in the aqueous solution was 10 mg/1, whereas the ozone concentration at the output of ozone generator was 30 mg/1. The complete inactivation of spores took 15 min. Selection of the temperature of water, the ozone concentrations and ultrasonic power allowed to determine the time necessary for destroying the row of microorganisms.

  18. Venturing into new realms? Microorganisms in space.

    Science.gov (United States)

    Moissl-Eichinger, Christine; Cockell, Charles; Rettberg, Petra

    2016-09-01

    One of the biggest challenges of science is the determination of whether extraterrestrial life exists. Although potential habitable areas might be available for complex life, it is more likely that microbial life could exist in space. Many extremotolerant and extremophilic microbes have been found to be able to withstand numerous, combined environmental factors, such as high or low temperatures and pressures, high-salt conditions, high doses of radiation, desiccation or nutrient limitations. They may even survive the transit from one planet to another. Terrestrial Mars-analogue sites are one focus of researchers, in order to understand the microbial diversity in preparation for upcoming space missions aimed at the detection of life. However, such missions could also pose a risk with respect to contamination of the extraterrestrial environment by accidentally transferred terrestrial microorganisms. Closer to the Earth, the International Space Station is the most enclosed habitat, where humans work and live-and with them numerous microorganisms. It is still unknown how microbes adapt to this environment, possibly even creating a risk for the crew. Information on the microbiology of the ISS will have an impact on the planning and implementation of long-term human spaceflights in order to ensure a safe, stable and balanced microbiome on board. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Bioremediation of trinitrotolulene by a ruminal microorganism

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Taejin; Williamson, K.J.; Craig, A.M. [Oregon State Univ., Corvallis, OR (United States)

    1995-10-01

    2,4,6-trinitrotoluene (TNT) has been widely used for the production of explosives because of its low boiling point, high stability, low impact sensitivity, and safe manufacture. More than 1,100 military facilities, each potentially contaminated with munitions waste, are expected to require treatment of more than one million cubic yards of contaminated soils. The cost associated with remediation of these sites has been estimated to be in excess of $1.5 billion. Recently, researchers have studied ruminal microorganisms in relation to their ability to degrade xenobiotic compounds. Many of these organisms are strict anaerobes with optimal redox potentials as low as -420 mV. Ruminal organisms have been shown capable of destroying some pesticides, such as parathion, p-nitrophenol, and biphenyl-type compounds; thiono isomers, and nitrogen-containing heterocyclic plant toxins such as the pyrrolizidine alkaloids. Many of these compounds have structures similar to TNT. A TNT-degrading ruminal microorganism has been isolated from goat rumen fluid with successive enrichments on triaminotoluene (TAT) and TNT. The isolate, designated G.8, utilizes nitrate and lactate as the primary energy source. G.8 was able to tolerate and metabolite levels of TNT up to the saturation point of 125 mg/l.

  20. Ionic liquid-tolerant microorganisms and microbial communities for lignocellulose conversion to bioproducts.

    Science.gov (United States)

    Yu, Chaowei; Simmons, Blake A; Singer, Steven W; Thelen, Michael P; VanderGheynst, Jean S

    2016-12-01

    Chemical and physical pretreatment of biomass is a critical step in the conversion of lignocellulose to biofuels and bioproducts. Ionic liquid (IL) pretreatment has attracted significant attention due to the unique ability of certain ILs to solubilize some or all components of the plant cell wall. However, these ILs inhibit not only the enzyme activities but also the growth and productivity of microorganisms used in downstream hydrolysis and fermentation processes. While pretreated biomass can be washed to remove residual IL and reduce inhibition, extensive washing is costly and not feasible in large-scale processes. IL-tolerant microorganisms and microbial communities have been discovered from environmental samples and studies begun to elucidate mechanisms of IL tolerance. The discovery of IL tolerance in environmental microbial communities and individual microbes has lead to the proposal of molecular mechanisms of resistance. In this article, we review recent progress on discovering IL-tolerant microorganisms, identifying metabolic pathways and mechanisms of tolerance, and engineering microorganisms for IL tolerance. Research in these areas will yield new approaches to overcome inhibition in lignocellulosic biomass bioconversion processes and increase opportunities for the use of ILs in biomass pretreatment.

  1. Development of microorganisms for cellulose-biofuel consolidated bioprocessings: metabolic engineers’ tricks

    Directory of Open Access Journals (Sweden)

    Roberto Mazzoli

    2012-10-01

    Full Text Available Cellulose waste biomass is the most abundant and attractive substrate for "biorefinery strategies" that are aimed to produce high-value products (e.g. solvents, fuels, building blocks by economically and environmentally sustainable fermentation processes. However, cellulose is highly recalcitrant to biodegradation and its conversion by biotechnological strategies currently requires economically inefficient multistep industrial processes. The need for dedicated cellulase production continues to be a major constraint to cost-effective processing of cellulosic biomass.Research efforts have been aimed at developing recombinant microorganisms with suitable characteristics for single step biomass fermentation (consolidated bioprocessing, CBP. Two paradigms have been applied for such, so far unsuccessful, attempts: a “native cellulolytic strategies”, aimed at conferring high-value product properties to natural cellulolytic microorganisms; b “recombinant cellulolytic strategies”, aimed to confer cellulolytic ability to microorganisms exhibiting high product yields and titers.By starting from the description of natural enzyme systems for plant biomass degradation and natural metabolic pathways for some of the most valuable product (i.e. butanol, ethanol, and hydrogen biosynthesis, this review describes state-of-the-art bottlenecks and solutions for the development of recombinant microbial strains for cellulosic biofuel CBP by metabolic engineering. Complexed cellulases (i.e. cellulosomes benefit from stronger proximity effects and show enhanced synergy on insoluble substrates (i.e. crystalline cellulose with respect to free enzymes. For this reason, special attention was held on strategies involving cellulosome/designer cellulosome-bearing recombinant microorganisms.

  2. Large-scale production of diesel-like biofuels - process design as an inherent part of microorganism development.

    Science.gov (United States)

    Cuellar, Maria C; Heijnen, Joseph J; van der Wielen, Luuk A M

    2013-06-01

    Industrial biotechnology is playing an important role in the transition to a bio-based economy. Currently, however, industrial implementation is still modest, despite the advances made in microorganism development. Given that the fuels and commodity chemicals sectors are characterized by tight economic margins, we propose to address overall process design and efficiency at the start of bioprocess development. While current microorganism development is targeted at product formation and product yield, addressing process design at the start of bioprocess development means that microorganism selection can also be extended to other critical targets for process technology and process scale implementation, such as enhancing cell separation or increasing cell robustness at operating conditions that favor the overall process. In this paper we follow this approach for the microbial production of diesel-like biofuels. We review current microbial routes with both oleaginous and engineered microorganisms. For the routes leading to extracellular production, we identify the process conditions for large scale operation. The process conditions identified are finally translated to microorganism development targets. We show that microorganism development should be directed at anaerobic production, increasing robustness at extreme process conditions and tailoring cell surface properties. All the same time, novel process configurations integrating fermentation and product recovery, cell reuse and low-cost technologies for product separation are mandatory. This review provides a state-of-the-art summary of the latest challenges in large-scale production of diesel-like biofuels. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Combining nonthermal technologies to control foodborne microorganisms.

    Science.gov (United States)

    Ross, Alexander I V; Griffiths, Mansel W; Mittal, Gauri S; Deeth, Hilton C

    2003-12-31

    Novel nonthermal processes, such as high hydrostatic pressure (HHP), pulsed electric fields (PEFs), ionizing radiation and ultrasonication, are able to inactivate microorganisms at ambient or sublethal temperatures. Many of these processes require very high treatment intensities, however, to achieve adequate microbial destruction in low-acid foods. Combining nonthermal processes with conventional preservation methods enhances their antimicrobial effect so that lower process intensities can be used. Combining two or more nonthermal processes can also enhance microbial inactivation and allow the use of lower individual treatment intensities. For conventional preservation treatments, optimal microbial control is achieved through the hurdle concept, with synergistic effects resulting from different components of the microbial cell being targeted simultaneously. The mechanisms of inactivation by nonthermal processes are still unclear; thus, the bases of synergistic combinations remain speculative. This paper reviews literature on the antimicrobial efficiencies of nonthermal processes combined with conventional and novel nonthermal technologies. Where possible, the proposed mechanisms of synergy is mentioned.

  4. Heterogeneity in isogenic populations of microorganisms

    DEFF Research Database (Denmark)

    Pedersen, Anne Egholm

    heterogeneity was detected when the culture had been propagated according to the guidelines of the Copenhagen School of Bacterial Growth Physiology. The L. lactis GFP reporter strain was more challenging to analyze. The population profile for this reporter strain was shown to be dependent on the type of medium...... values for quantifiable variables are used. The reproducibility of an experiment could thus be affected by the presence of subpopulations or high levels of phenotypic variations. Ole Maaløe and colleagues did in the late 1950’ties observe that the growth rate, RNA, DNA and protein synthesis and cell...... factor per unit of time. The use of a balanced growing culture is a cornerstone in the Copenhagen School of Bacterial Growth Physiology headed by Ole Maaløe. Due to the size of the microorganism it is challenging to measure a quantifiable variable in a single cell. However, fluorescence, whether being...

  5. Responsive Polydiacetylene Vesicles for Biosensing Microorganisms

    Directory of Open Access Journals (Sweden)

    Estelle Lebègue

    2018-02-01

    Full Text Available Polydiacetylene (PDA inserted in films or in vesicles has received increasing attention due to its property to undergo a blue-to-red colorimetric transition along with a change from non-fluorescent to fluorescent upon application of various stimuli. In this review paper, the principle for the detection of various microorganisms (bacteria, directly detected or detected through the emitted toxins or through their DNA, and viruses and of antibacterial and antiviral peptides based on these responsive PDA vesicles are detailed. The analytical performances obtained, when vesicles are in suspension or immobilized, are given and compared to those of the responsive vesicles mainly based on the vesicle encapsulation method. Many future challenges are then discussed.

  6. Pathogenic microorganisms of medicinal herbal drugs

    Directory of Open Access Journals (Sweden)

    Stević Tatjana

    2012-01-01

    Full Text Available All the parts of plants (root, leaf, flower naturally have a high level of microorganisms, bacteria and fungi, especially molds. Microbial contamination could be a result of inappropriate harvesting, cleaning of the raw plant material, unhygienic processing of the plants, unsuitable transport and storage. After examination of over 40 dried medicinal plant species, the lowest microbial quality was determined for Maydis stigma, Mentha leaf and herb, Equisetum herb, Calendula flower, Urtica leaf, Melissa leaf, Serpylli herb, Chamomilla flower etc. Although mixed infections are recorded with different types of fungus, Fusarium was observed as the most dominant genus in most of the tested drugs, followed by Aspergillus and Alternaria. In addition to these fungi species from the following genera were identified: Phoma, Cephalosporium, Nigrospora, Cladosporium, Epicoccum, Gliocladium, Myrothecium, Cercospora, Phomopsis, Verticillium, Dreschlera (=Bipolaris, Rhizoctonia, Septoria, Trichoderma, Curvularia, Stachybotrys, Trichothecium, Puccinia, Botrytis, Mucor and Rhizopus sp., depending on plant species.

  7. Artificial inorganic Biohybrids: the functional combination of microorganisms and cells with inorganic materials.

    Science.gov (United States)

    Holzmeister, Ib; Schamel, Martha; Groll, Jürgen; Gbureck, Uwe; Vorndran, Elke

    2018-04-23

    Biohybrids can be defined as the functional combination of proteins, viable cells or microorganisms with non-biological materials. This article reviews recent findings on the encapsulation of microorganisms and eukaryotic cells in inorganic matrices such as silica gels or cements. The entrapment of biological entities into a support material is of great benefit for processing since the encapsulation matrix protects sensitive cells from shear forces, unfavourable pH changes, or cytotoxic solvents, avoids culture-washout, and simplifies the separation of formed products. After reflecting general aspects of such an immobilization as well as the chemistry of the inorganic matrices, we focused on manufacturing aspects and the application of such biohybrids in biotechnology, medicine as well as in environmental science and for civil engineering purpose. The encapsulation of living cells and microorganisms became an intensively studied and rapidly expanding research field with manifold applications in medicine, bio- and environmental technology, or civil engineering. Here, the use of silica or cements as encapsulation matrices have the advantage of a higher chemical and mechanical resistance towards harsh environmental conditions during processing compared to their polymeric counterparts. In this perspective, the article gives an overview about the inorganic material systems used for cell encapsulation, followed by reviewing the most important applications. The future may lay in a combination of the currently achieved biohybrid systems with additive manufacturing techniques. In a longer perspective, this would enable the direct printing of cell loaded bioreactor components. Copyright © 2018. Published by Elsevier Ltd.

  8. Identification of subsurface microorganisms at Yucca Mountain

    International Nuclear Information System (INIS)

    Stetzenbach, L.D.

    1994-01-01

    Bacteria isolated from ground water samples taken from 31 springs during 1993 were collected and processed according to procedures described in earlier reports. These procedures required aseptic collection of surface water samples in sterile screw-capped containers, transportation to the HRC microbiology laboratory, and culture by spread plating onto R2A medium. The isolates were further processed for identification using a gas chromatographic analysis of fatty acid methyl esters (FAME) extracted from cell membranes. This work generated a presumptive identification of 113 bacterial species distributed among 45 genera using a database obtained from Microbial ID, Inc., Newark, Delaware (MIDI). A preliminary examination of the FAME data was accomplished using cluster analysis and principal component analysis software obtained from MIDI. Typically, bacterial strains that cluster at less than 10 Euclidian distance units have fatty acid patterns consistent among members of the same species. Thus an organism obtained from one source can be recognized if it is isolated again from the same or any other source. This makes it possible to track the distribution of organisms and monitor environmental conditions or fluid transport mechanisms. Microorganisms are seldom found as monocultures in natural environments. They are more likely to be closely associated with other genera with complementary metabolic requirements. An understanding of the indigenous microorganism population is useful in understanding subtle changes in the environment. However, classification of environmental organisms using traditional methods is not ideal because differentiation of species with small variations or genera with very similar taxonomic characteristics is beyond the capabilities of traditional microbiological methods

  9. Interactions of phytoplankton, zooplankton and microorganisms

    Science.gov (United States)

    Pomeroy, L. R.; Paffenhöfer, G.-A.; Yoder, J. A.

    We present evidence that there are significant interactions between heterotrophic microorganisms, doliolids and Fritillaria within intrusions of nutrient-rich Gulf Stream water stranding on the continental shelf. During the summer of 1981 cold, nutrient-rich water from below the surface of the Gulf Stream was repeatedly intruded and stranded on the continental shelf off northeastern Florida. On August 6 old, stranded Gulf Stream water depleted of nitrate occupied the lower layer on the outer shelf. The upper water was continental shelf water, older but of undefined age. On August 6 free-living bacteria were >10 6ml -1 everywhere at all depths, an order of magnitude greater than normal bacterial numbers on the northeastern Florida continental shelf. Over 10 days the numbers of free bacteria doubled while bacteria attached to particles increased by a factor of four. The adenylate/chlorophyll ratio showed that phytoplankton dominated the lower layers of intruded water, while the surface water became increasingly dominated by heterotrophic microorganisms (bacteria and protozoa) over 10 days. There were significant, negative correlations between bacteria and doliolids and between bacteria and Fritillaria. Regions of maximum bacterial numbers did not coincide with locations of salp swarms. The increased numbers of bacteria at all depths in a highly stratified system in which most phytoplankton are in the lower layer suggests a diverse source of bacterial growth substrates, some of which involve zooplankton as intermediaries. Production of autotrophs is more than twice that of microheterotrophs on average, but because of their differential distribution, microheterotrophs are the dominant biomass in much of the surface water and may be significant in energy flux to metazoan consumers as well as competitors for mutually useable sources of nutrition.

  10. System for identification of microorganism and detection of infectious disorder

    DEFF Research Database (Denmark)

    2013-01-01

    Methods for the identification of microorganisms or infectious disorders are disclosed, comprising obtaining a suitable sample from sources such as persons, animals, plants, food, water or soil. The methods also comprise providing tailored nucleic acid substrate(s) designed to react with a type 1...... topoisomerase from one or more microorganism(s) or infectious agent(s), and incubating said substrate with said sample, or extracts or preparations from the sample, so that the substrate is processed by said topoisomerase if said microorganism(s) or infectious agent(s) is present in the sample. Finally......, processed substrates are identified and potentially quantified by one or more of a range of standard molecular biology methods and read-out systems. The identification and potential quantification of microorganisms and infectious agents, including but not limited to Plasmodium falciparum and Mycobacterium...

  11. Enhancement of uranium-accumulating ability of microorganisms by irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Sakaguchi, Takashi; Nakajima, Akira; Tsuruta, Takehiko [Miyazaki Medical Coll., Kiyotake (Japan)

    1998-01-01

    Some microorganisms having excellent ability to accumulate uranium were isolated, from soil and water systems in and around the Ningyo-toge Station of Power Reactor and Nuclear Fuel Development Corporation. The enhancement of uranium-accumulating ability of microorganisms by electron-beam irradiation was examined, and the ability of JW-046 was increased 3-5% by the irradiation. The irradiation affect the growth of some of microorganisms tested. (author)

  12. Plasma inactivation of food-related microorganisms in liquids

    International Nuclear Information System (INIS)

    Marsili, Lisa; Espie, Steven; Anderson, J.G.John G.; MacGregor, S.J.Scott J.

    2002-01-01

    This paper reports on a plasma process that inactivates microorganisms in liquids through the application of high-voltage pulses. These pulses result in breakdown of the gas and liquid layers, producing many active species such as UV photons, ozone, free radicals and free electrons. Several test microorganisms representing a range of problematic microorganisms were investigated. Significant reductions in microbial population were achieved, demonstrating the effectiveness of using the plasma discharge process to treat contaminated liquids

  13. Final report for Assembling Microorganisms into Energy Converting Materials

    Energy Technology Data Exchange (ETDEWEB)

    Sahin, Ozgur

    2018-03-26

    The goal of this project was to integrate microorganisms capable of reversible energy transduction in response to changing relative humidity with non-biological materials to create hybrid energy conversion systems. While plants and many other biological organisms have developed structures that are extraordinarily effective in converting changes in relative humidity into mechanical energy, engineered energy transduction systems rarely take advantage of this powerful phenomenon. Rather than developing synthetic materials that can convert changes in relative humidity in to mechanical energy, we developed approaches to assemble bacterial spores into larger materials. These materials can convert energy from evaporation of water in dry atmospheric conditions, which we demonstrated by building energy harvesters from these materials. We have also developed experiments to investigate the interaction of water with the spore material, and to determine how this interaction imposes limits on energy conversion. In addition, we carried out theoretical calculations to investigate the limits imposed by the environmental conditions to the power available in the energy harvesting process. These calculations took into account heat and water vapor transfer in the atmosphere surrounding the spore based materials. Overall, our results suggest that biomolecular materials are promising candidates to convert energy from evaporation.

  14. Predicting hydrocarbon release from soil

    International Nuclear Information System (INIS)

    Poppendieck, D.; Loehr, R.C.

    2002-01-01

    'Full text:' The remediation of hazardous chemicals from soils can be a lengthy and costly process. As a result, recent regulatory initiatives have focused on risk-based corrective action (RBCA) approaches. Such approaches attempt to identify the amount of chemical that can be left at a site with contaminated soil and still be protective of human health and the environment. For hydrocarbons in soils to pose risk to human heath and the environment, the hydrocarbons must be released from the soil and accessible to microorganisms, earthworms, or other higher level organisms. The sorption of hydrocarbons to soil can reduce the availability of the hydrocarbon to receptors. Typically in soils and sediments, there is an initial fast release of a hydrocarbon from the soil to the aqueous phase followed by a slower release of the remaining hydrocarbon to the aqueous phase. The rate and extent of slow release can influence aqueous hydrocarbon concentrations and the fate and transport of hydrocarbons in the subsurface. Once the fast fraction of the chemical has been removed from the soil, the remaining fraction of a chemical may desorb at a rate that natural mechanisms can attenuate the released hydrocarbon. Hence, active remediation may be needed only until the fast fraction has been removed. However, the fast fraction is a soil and chemical specific parameter. This presentation will present a tier I type protocol that has been developed to quickly estimate the fraction of hydrocarbons that are readily released from the soil matrix to the aqueous phase. Previous research in our laboratory and elsewhere has used long-term desorption (four months) studies to determine the readily released fraction. This research shows that a single short-term (less than two weeks) batch extraction procedure provides a good estimate of the fast released fraction derived from long-term experiments. This procedure can be used as a tool to rapidly evaluate the release and bioavailability of

  15. Radiation resistance of microorganisms on unsterilized infusion sets

    DEFF Research Database (Denmark)

    Christensen, E. Ahrensburg; Kristensen, H.; Hoborn, J.

    1991-01-01

    Three different methods were used for detecting and isolating microorganisms with high radiation resistance from the microbial contamination on infusion sets prior to sterilization. By all three methods, microorganisms with a radiation resistance high enough to be a critical factor in a steriliza......Three different methods were used for detecting and isolating microorganisms with high radiation resistance from the microbial contamination on infusion sets prior to sterilization. By all three methods, microorganisms with a radiation resistance high enough to be a critical factor...

  16. Esterase screening using whole cells of Brazilian soil microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Mantovani, Simone M.; Oliveira, Luciana G. de; Marsaioli, Anita J., E-mail: anita@iqm.unicamp.b [Universidade Estadual de Campinas (IQ/UNICAMP), SP (Brazil). Inst. de Quimica

    2010-07-01

    A miniaturized enzymatic assay using fluorescent probes to reveal esterase producing microorganisms was optimized and applied to screen 64 soil bacterial strains. The best results were validated using traditional non-fluorogenic assays with acetyl and propanoyl phenylethanol to confirm the miniaturized results. The most active microorganisms belong to the genus Bacillus showing esterase activity and good enantiomeric ratios for the resolution of phenylethanol derivatives (E > 30). Part of the microorganisms are kept in our laboratory in glycerol or freezedried and the best microorganisms will be deposited in the CBMAI/CPQBA/UNICAMP culture collection. (author)

  17. [Characteristics of proteins synthesized by hydrogen-oxidizing microorganisms].

    Science.gov (United States)

    Volova, T G; Barashkov, V A

    2010-01-01

    The study was conducted to determine the biological value of proteins synthesized by hydrogen-oxidizing microorganisms--the hydrogen bacteria Alcaligenes eutrophus Z1 and Ralstonia eutropha B5786 and the CO-resistant strain of carboxydobacterium Seliberia carboxydohydrogena Z1062. Based on a number of significant parameters characterizing the biological value of a product, the proteins of hydrogen-oxidizing microorganisms have been found to occupy an intermediate position between traditional animal and plant proteins. The high total protein in biomass of these microorganisms, their complete amino acid content, and availability to proteolytic enzymes allow for us to consider these microorganisms as potential protein producers.

  18. Bioremediation of Industrial Waste Through Enzyme Producing Marine Microorganisms.

    Science.gov (United States)

    Sivaperumal, P; Kamala, K; Rajaram, R

    Bioremediation process using microorganisms is a kind of nature-friendly and cost-effective clean green technology. Recently, biodegradation of industrial wastes using enzymes from marine microorganisms has been reported worldwide. The prospectus research activity in remediation area would contribute toward the development of advanced bioprocess technology. To minimize industrial wastes, marine enzymes could constitute a novel alternative in terms of waste treatment. Nowadays, the evidence on the mechanisms of bioremediation-related enzymes from marine microorganisms has been extensively studied. This review also will provide information about enzymes from various marine microorganisms and their complexity in the biodegradation of comprehensive range of industrial wastes. © 2017 Elsevier Inc. All rights reserved.

  19. Inactivation of microorganisms within collagen gel biomatrices using pulsed electric field treatment.

    Science.gov (United States)

    Griffiths, Sarah; Maclean, Michelle; Anderson, John G; MacGregor, Scott J; Grant, M Helen

    2012-02-01

    Pulsed electric field (PEF) treatment was examined as a potential decontamination method for tissue engineering biomatrices by determining the susceptibility of a range of microorganisms whilst within a collagen gel. High intensity pulsed electric fields were applied to collagen gel biomatrices containing either Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, Candida albicans, Saccharomyces cerevisiae or the spores of Aspergillus niger. The results established varying degrees of microbial PEF susceptibility. When high initial cell densities (10(6)-10(7) CFU ml(-1)) were PEF treated with 100 pulses at 45 kV cm(-1), the greatest log reduction was achieved with S. cerevisiae (~6.5 log(10) CFU ml(-1)) and the lowest reduction achieved with S. epidermidis (~0.5 log(10) CFU ml(-1)). The results demonstrate that inactivation is influenced by the intrinsic properties of the microorganism treated. Further investigations are required to optimise the microbial inactivation kinetics associated with PEF treatment of collagen gel biomatrices.

  20. Recent advances and industrial viewpoint for biological treatment of wastewaters by oleaginous microorganisms.

    Science.gov (United States)

    Huang, Chao; Luo, Mu-Tan; Chen, Xue-Fang; Xiong, Lian; Li, Xiao-Mei; Chen, Xin-De

    2017-05-01

    Recently, technology of using oleaginous microorganisms for biological treatment of wastewaters has become one hot topic in biochemical and environmental engineering for its advantages such as easy for operation in basic bioreactor, having potential to produce valuable bio-products, efficient wastewaters treatment in short period, etc. To promote its industrialization, this article provides some comprehensive analysis of this technology such as its advances, issues, and outlook especially from industrial viewpoint. In detail, the types of wastewaters can be treated and the kinds of oleaginous microorganisms used for biological treatment are introduced, the potential of industrial application and issues (relatively low COD removal, low lipid yield, cost of operation, and lack of scale up application) of this technology are presented, and some critical outlook mainly on co-culture method, combination with other treatments, process controlling and adjusting are discussed systematically. By this article, some important information to develop this technology can be obtained. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. The effect of effective microorganisms (EM on EBPR in modified contact stabilization system

    Directory of Open Access Journals (Sweden)

    Ehab M. Rashed

    2015-12-01

    Full Text Available Excessive phosphorus can cause eutrophication in water bodies and needs to be reduced in most wastewaters before discharge to receiving waters. The enhanced biological phosphorus removal (EBPR process has been shown to be an economical and environmentally compatible method for reducing phosphorus from wastewaters. The experiment has been performed in order to investigate the effect of using effective microorganisms (EM as an application of Enhanced Biological Phosphorous Removal (EBPR in modified contact stabilization activated sludge system by using contact tank as a phosphorus uptake zone and using thickener tank as a phosphorus release zone. The study involved the construction of a pilot plant which was setup in the Quhafa Wastewater Treatment Plant (WWTP, Al Fayoum, Egypt. Then the uptake and release of total phosphorus were determined through two batch tests using sludge samples from thickener and stabilization tanks. Results showed the removal efficiencies of Chemical Oxygen Demand (COD, Biological Oxygen Demand (BOD5 and total phosphorus (TP of this pilot plant were 93%, 93% and 90%, respectively. On the other hand the results of batch tests showed that the reason for high ability of phosphorus removal by this pilot plant is related to the high performance of microorganisms for phosphorus accumulation. Finally providing activated EM to the anaerobic zone was to improve fermentation by achieving the enhancement of the performance of phosphorus accumulating organisms (PAOs and then increase phosphorous release resulting in the decrease of the average effluent phosphorus concentration.

  2. Microorganism-mediated behaviour of malaria mosquitoes

    NARCIS (Netherlands)

    Busula, Annette O.

    2017-01-01

    Host-seeking is an important component of mosquito vectorial capacity on which the success of the other behavioural determinants depends. Blood-seeking mosquitoes are mainly guided by chemical cues released by their blood hosts. This thesis describes results of a study that determined the effect

  3. Systems engineering and integration as a foundation for mission engineering

    OpenAIRE

    Beam, David F.

    2015-01-01

    Approved for public release; distribution is unlimited This paper investigates the emerging term mission engineering through the framework of systems engineering and systems integration. Systems engineering concepts, processes, and methodologies are extrapolated for use in conjunction with a systems integration, life-cycle based framework to effect mission engineering. The specific systems engineering concepts of measures of effectiveness, performance and suitability are recommended as fou...

  4. Synthetic constructs in/for the environment: managing the interplay between natural and engineered Biology.

    Science.gov (United States)

    Schmidt, Markus; de Lorenzo, Víctor

    2012-07-16

    The plausible release of deeply engineered or even entirely synthetic/artificial microorganisms raises the issue of their intentional (e.g. bioremediation) or accidental interaction with the Environment. Containment systems designed in the 1980s-1990s for limiting the spread of genetically engineered bacteria and their recombinant traits are still applicable to contemporary Synthetic Biology constructs. Yet, the ease of DNA synthesis and the uncertainty on how non-natural properties and strains could interplay with the existing biological word poses yet again the challenge of designing safe and efficacious firewalls to curtail possible interactions. Such barriers may include xeno-nucleic acids (XNAs) instead of DNA as information-bearing molecules, rewriting the genetic code to make it non-understandable by the existing gene expression machineries, and/or making growth dependent on xenobiotic chemicals. Copyright © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  5. Glyphosate-Degrading Microorganisms from Industrial Activated Sludge

    OpenAIRE

    Balthazor, Terry M.; Hallas, Laurence E.

    1986-01-01

    A plating medium was developed to isolate N-phosphonomethylglycine (glyphosate)-degrading microorganisms, with glyphosate as the sole phosphorus source. Two industrial biosystems treating glyphosate wastes contained elevated microbial counts on the medium. One purified isolate metabolized glyphosate to aminomethylphosphonic acid, mineralizing this accumulating intermediate during log growth. This microorganism has been identified as a Flavobacterium species.

  6. Microorganisms associated with the spoilage of avocado pear ...

    African Journals Online (AJOL)

    The microorganisms associated with the spoilage of Avocado pear, Persea americana fruits, purchased fresh from various markets in Benin City were investigated. The pour plate method was used for the isolation. A total of nine species of microorganisms were isolated and identified in this study. They comprise of seven ...

  7. the economic importance of microorganism in food processing

    African Journals Online (AJOL)

    BSN

    This paper attempts to highlight the Economic Importance of microorganisms in food processing and manufacturing; it goes further to differentiate between the desirable ... Desirable importance are those cost saving and revenue generating activities ... Microorganism (yeast) play very useful role in the Bakery industries.

  8. Gut Microorganisms Found Necessary for Successful Cancer Therapy | Poster

    Science.gov (United States)

    By Nancy Parrish, Staff Writer Humans play host to trillions of microorganisms that help our bodies perform basic functions, like digestion, growth, and fighting disease. In fact, bacterial cells outnumber the human cells in our bodies by 10 to 1.1 The tens of trillions of microorganisms thriving in our intestines are known as gut microbiota, and those that are not harmful to

  9. 78 FR 42451 - Animal Feeds Contaminated With Salmonella Microorganisms

    Science.gov (United States)

    2013-07-16

    .... FDA-2013-N-0253] Animal Feeds Contaminated With Salmonella Microorganisms AGENCY: Food and Drug... revoking an advisory opinion on animal feeds contaminated with Salmonella microorganisms. This action is... articulated in a final compliance policy guide (CPG) on Salmonella in food for animals. DATES: This rule is...

  10. Effects of heat-activated persulfate oxidation on soil microorganisms

    DEFF Research Database (Denmark)

    Tsitonaki, Aikaterini; Smets, Barth F.; Bjerg, Poul Løgstrup

    2008-01-01

    /L). The results emphasize the necessity of using multiple toxicity assays and indigenous cultures in order to realistically assess the potential effects of in situ chemical oxidation on soil microorganisms. A comparison to other studies suggests that the effects of activated persulfate on soil microorganisms...

  11. Titanium photocatalyst against human pathogenic microorganisms

    International Nuclear Information System (INIS)

    Kussovski, V.; Stefchev, P.; Kirilov, R.

    2011-01-01

    The conventional methods of disinfection are not effective in the longer term. They are time and staff intensive and use aggressive chemicals. Photocatalytic oxidation on surfaces coated with titanium dioxide (TiO 2 ) might offer a possible alternative. The antimicrobial activity of TiO 2 powder P25 and thin films of TiO 2 on glass slides against representative strains of microorganisms associated with hospital-acquired infections (Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans) was investigated in vitro. High efficiency has been found in the case of the studied bacterial strains, particularly for the P. aeruginosa. It was shown that it is possible to disinfect surfaces coated with TiO 2 and stimulated by UV-A light. The reduction efficiencies for P. aeruginosa, S. aureus and C. albicans were 3.19, 2.32 and 1.22. In all cases sublethal UV-A doses provoked an important lethality in the presence of TiO 2 . (authors)

  12. Heavy metal removal and recovery using microorganisms

    International Nuclear Information System (INIS)

    Wilde, E.W.; Benemann, J.R.

    1991-02-01

    Microorganisms -- bacteria, fungi, and microalgae -- can accumulate relatively large amounts of toxic heavy metals and radionuclides from the environment. These organisms often exhibit specificity for particular metals. The metal content of microbial biomass can be a substantial fraction of total dry weight with concentration factors (metal in dry biomass to metal in solution) exceeding one million in some cases. Both living and inert (dead) microbial biomass can be used to reduce heavy metal concentrations in contaminated waters to very low levels -- parts per billion and even lower. In many respects (e.g. specificity, residual metal concentrations, accumulation factors, and economics) microbial bioremoval processes can be superior to conventional processes, such as ion exchange and caustic (lime or hydroxide) precipitation for heavy metals removal from waste and contaminated waters. Thus, bioremoval could be developed to contribute to the clean-up of wastes at the Savannah River Site (SRS) and other DOE facilities. However, the potential advantages of bioremoval processes must still be developed into practical operating systems. A detailed review of the literature suggests that appropriate bioremoval processes could be developed for the SRS. There is great variability from one biomass source to another in bioremoval capabilities. Bioremoval is affected by pH, other ions, temperature, and many other factors. The biological (living vs. dead) and physical (immobilized vs. dispersed) characteristics of the biomass also greatly affect metal binding. Even subtle differences in the microbial biomass, such as the conditions under which it was cultivated, can have major effects on heavy metal binding

  13. Heavy metal removal and recovery using microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Wilde, E.W. (Westinghouse Savannah River Co., Aiken, SC (United States)); Benemann, J.R. (Benemann (J.R.), Pinole, CA (United States))

    1991-02-01

    Microorganisms -- bacteria, fungi, and microalgae -- can accumulate relatively large amounts of toxic heavy metals and radionuclides from the environment. These organisms often exhibit specificity for particular metals. The metal content of microbial biomass can be a substantial fraction of total dry weight with concentration factors (metal in dry biomass to metal in solution) exceeding one million in some cases. Both living and inert (dead) microbial biomass can be used to reduce heavy metal concentrations in contaminated waters to very low levels -- parts per billion and even lower. In many respects (e.g. specificity, residual metal concentrations, accumulation factors, and economics) microbial bioremoval processes can be superior to conventional processes, such as ion exchange and caustic (lime or hydroxide) precipitation for heavy metals removal from waste and contaminated waters. Thus, bioremoval could be developed to contribute to the clean-up of wastes at the Savannah River Site (SRS) and other DOE facilities. However, the potential advantages of bioremoval processes must still be developed into practical operating systems. A detailed review of the literature suggests that appropriate bioremoval processes could be developed for the SRS. There is great variability from one biomass source to another in bioremoval capabilities. Bioremoval is affected by pH, other ions, temperature, and many other factors. The biological (living vs. dead) and physical (immobilized vs. dispersed) characteristics of the biomass also greatly affect metal binding. Even subtle differences in the microbial biomass, such as the conditions under which it was cultivated, can have major effects on heavy metal binding.

  14. Snow as a habitat for microorganisms

    Science.gov (United States)

    Hoham, Ronald W.

    1989-01-01

    There are three major habitats involving ice and snow, and the microorganisms studied from these habitats are most eukaryotic. Sea ice is inhabited by algae called diatoms, glacial ice has sparse populations of green algai cal desmids, and the temporary and permanent snows in mountainous regions and high latitudes are inhabited mostly by green algal flagellates. The life cycle of green algal flagellates is summarized by discussing the effects of light, temperature, nutrients, and snow melts. Specific examples of optimal conditions and environmental effects for various snow algae are given. It is not likely that the eukaryotic snow algae presented are candidated for life on the planet Mars. Evolutionally, eukaryotic cells as know on Earth may not have had the opportunity to develop on Mars (if life evolved at all on Mars) since eukaryotes did not appear on Earth until almost two billion years after the first prokaryotic organisms. However, the snow/ice ecosystems on Earth present themselves as extreme habitats were there is evidence of prokaryotic life (eubacteria and cyanbacteria) of which literally nothing is known. Any future surveillances of extant and/or extinct life on Mars should include probes (if not landing sites) to investigate sites of concentrations of ice water. The possibility of signs of life in Martian polar regions should not be overlooked.

  15. Cyanide utilization and degradation by microorganisms.

    Science.gov (United States)

    Knowles, C J

    1988-01-01

    Various microorganisms can produce (cyanogenesis) or degrade cyanide. They degrade cyanide either to detoxify it, or to use it as a source of nitrogen for growth. Significant amounts of cyanide are formed as a secondary metabolite by a wide range of fungi and a few bacteria by decarboxylation of glycine. When cyanide has been formed by the snow mould fungus it is degraded by conversion to carbon dioxide and ammonia via an unknown pathway. In contrast, cyanogenic bacteria either do not further catabolize cyanide or they convert it into beta-cyanoalanine by addition to cysteine or O-acetylserine. Several non-cyanogenic fungi that are pathogens of cyanogenic plants are known to degrade cyanide by hydration to formamide by the enzyme cyanide hydratase. Such fungi can be immobilized and used in packed-cell columns to continuously detoxify cyanide. ICI Biological Products Business market a preparation of spray-dried fungal mycelia, 'CYCLEAR', to detoxify industrial wastes. Novo Industri have also introduced a cyanidase preparation to convert cyanide directly into formate and ammonia. Bacteria have been isolated that use cyanide as a source of nitrogen for growth. Because cyanide, as KCN or NaCN, is toxic for growth, the bacteria (Pseudomonas fluorescens) have to be grown in fed-batch culture with cyanide as the limiting nutrient. Cyanide is converted to carbon dioxide and ammonia (which is then assimilated) by an NADH-linked cyanide oxygenase system.

  16. Dynamic size spectrometry of airborne microorganisms: Laboratory evaluation and calibration

    Science.gov (United States)

    Qian, Yinge; Willeke, Klaus; Ulevicius, Vidmantas; Grinshpun, Sergey A.; Donnelly, Jean

    Bioaerosol samplers need to be calibrated for the microorganisms of interest. The Aerosizer, a relatively new aerodynamic size spectrometer, is shown to be a suitable dynamic instrument for the evaluation and calibration of such samplers in the laboratory, prior to their use in the field. It provides the necessary reference count against which the microbiological response of the sampler can be compared. It measures the health-significant aerodynamic diameters of microorganisms down to 0.5 μm, thus including most of the bacteria, fungi and pollen found in outdoor and indoor air environments. Comparison tests with a laser size spectrometer indicate that the suspension of microorganisms needs to be washed several times before aerosolization to avoid coating of the airborne microorganisms with nutrients and microbial slime from the suspension, and to reduce the residue particles to sizes below the lowest size of the aerosolized microorganisms.

  17. Biodiesel production by various oleaginous microorganisms from organic wastes.

    Science.gov (United States)

    Cho, Hyun Uk; Park, Jong Moon

    2018-05-01

    Biodiesel is a biodegradable and renewable fuel. A large amount of research has considered microbial oil production using oleaginous microorganisms, but the commercialization of microbial lipids produced in this way remains uncertain due to the high cost of feedstock or low lipid yield. Microbial lipids can be typically produced by microalgae, yeasts, and bacteria; the lipid yields of these microorganisms can be improved by using sufficient concentrations of organic carbon sources. Therefore, combining low-cost organic compounds contained in organic wastes with cultivation of oleaginous microorganisms can be a promising approach to obtain commercial viability. However, to achieve effective bioconversion of low-cost substrates to microbial lipids, the characteristics of each microorganism and each substrate should be considered simultaneously. This article discusses recent approaches to developing cost-effective microbial lipid production processes that use various oleaginous microorganisms and organic wastes. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Modelling and application of the inactivation of microorganism

    International Nuclear Information System (INIS)

    Oğuzhan, P.; Yangılar, F.

    2013-01-01

    Prevention of consuming contaminated food with toxic microorganisms causing infections and consideration of food protection and new microbial inactivation methods are obligatory situations. Food microbiology is mainly related with unwanted microorganisms spoiling foods during processing and transporting stages and causing diseases. Determination of pathogen microorganisms is important for human health to define and prevent dangers and elongate shelf life. Inactivation of pathogen microorganisms can provide food security and reduce nutrient losses. Microbial inactivation which is using methods of food protection such as food safety and fresh. With this aim, various methods are used such as classical thermal processes (pasteurisation, sterilisation), pressured electrical field (PEF), ionised radiation, high pressure, ultrasonic waves and plasma sterilisation. Microbial inactivation modelling is a secure and effective method in food production. A new microbiological application can give useful results for risk assessment in food, inactivation of microorganisms and improvement of shelf life. Application and control methods should be developed and supported by scientific research and industrial applications

  19. Biocommodity Engineering.

    Science.gov (United States)

    Lynd; Wyman; Gerngross

    1999-10-01

    The application of biotechnology to the production of commodity products (fuels, chemicals, and materials) offering benefits in terms of sustainable resource supply and environmental quality is an emergent area of intellectual endeavor and industrial practice with great promise. Such "biocommodity engineering" is distinct from biotechnology motivated by health care at multiple levels, including economic driving forces, the importance of feedstocks and cost-motivated process engineering, and the scale of application. Plant biomass represents both the dominant foreseeable source of feedstocks for biotechnological processes as well as the only foreseeable sustainable source of organic fuels, chemicals, and materials. A variety of forms of biomass, notably many cellulosic feedstocks, are potentially available at a large scale and are cost-competitive with low-cost petroleum whether considered on a mass or energy basis, and in terms of price defined on a purchase or net basis for both current and projected mature technology, and on a transfer basis for mature technology. Thus the central, and we believe surmountable, impediment to more widespread application of biocommodity engineering is the general absence of low-cost processing technology. Technological and research challenges associated with converting plant biomass into commodity products are considered relative to overcoming the recalcitrance of cellulosic biomass (converting cellulosic biomass into reactive intermediates) and product diversification (converting reactive intermediates into useful products). Advances are needed in pretreatment technology to make cellulosic materials accessible to enzymatic hydrolysis, with increased attention to the fundamental chemistry operative in pretreatment processes likely to accelerate progress. Important biotechnological challenges related to the utilization of cellulosic biomass include developing cellulase enzymes and microorganisms to produce them, fermentation of

  20. Impact on Human Health of Microorganisms Present in Fermented Dairy Products: An Overview

    Directory of Open Access Journals (Sweden)

    María Fernández

    2015-01-01

    Full Text Available Fermented dairy products provide nutrients in our diet, some of which are produced by the action of microorganisms during fermentation. These products can be populated by a diverse microbiota that impacts the organoleptic and physicochemical characteristics foods as well as human health. Acidification is carried out by starter lactic acid bacteria (LAB whereas other LAB, moulds, and yeasts become dominant during ripening and contribute to the development of aroma and texture in dairy products. Probiotics are generally part of the nonstarter microbiota, and their use has been extended in recent years. Fermented dairy products can contain beneficial compounds, which are produced by the metabolic activity of their microbiota (vitamins, conjugated linoleic acid, bioactive peptides, and gamma-aminobutyric acid, among others. Some microorganisms can also release toxic compounds, the most notorious being biogenic amines and aflatoxins. Though generally considered safe, fermented dairy products can be contaminated by pathogens. If proliferation occurs during manufacture or storage, they can cause sporadic cases or outbreaks of disease. This paper provides an overview on the current state of different aspects of the research on microorganisms present in dairy products in the light of their positive or negative impact on human health.

  1. Impact on human health of microorganisms present in fermented dairy products: an overview.

    Science.gov (United States)

    Fernández, María; Hudson, John Andrew; Korpela, Riitta; de los Reyes-Gavilán, Clara G

    2015-01-01

    Fermented dairy products provide nutrients in our diet, some of which are produced by the action of microorganisms during fermentation. These products can be populated by a diverse microbiota that impacts the organoleptic and physicochemical characteristics foods as well as human health. Acidification is carried out by starter lactic acid bacteria (LAB) whereas other LAB, moulds, and yeasts become dominant during ripening and contribute to the development of aroma and texture in dairy products. Probiotics are generally part of the nonstarter microbiota, and their use has been extended in recent years. Fermented dairy products can contain beneficial compounds, which are produced by the metabolic activity of their microbiota (vitamins, conjugated linoleic acid, bioactive peptides, and gamma-aminobutyric acid, among others). Some microorganisms can also release toxic compounds, the most notorious being biogenic amines and aflatoxins. Though generally considered safe, fermented dairy products can be contaminated by pathogens. If proliferation occurs during manufacture or storage, they can cause sporadic cases or outbreaks of disease. This paper provides an overview on the current state of different aspects of the research on microorganisms present in dairy products in the light of their positive or negative impact on human health.

  2. Stimuli responsive nanomaterials for controlled release applications

    KAUST Repository

    Li, Song

    2012-01-01

    The controlled release of therapeutics has been one of the major challenges for scientists and engineers during the past three decades. Coupled with excellent biocompatibility profiles, various nanomaterials have showed great promise for biomedical applications. Stimuli-responsive nanomaterials guarantee the controlled release of cargo to a given location, at a specific time, and with an accurate amount. In this review, we have combined the major stimuli that are currently used to achieve the ultimate goal of controlled and targeted release by "smart" nanomaterials. The most heavily explored strategies include (1) pH, (2) enzymes, (3) redox, (4) magnetic, and (5) light-triggered release.

  3. Formation of methylamine by rumen microorganisms

    International Nuclear Information System (INIS)

    Itabashi, Hisao; Kandatsu, Makoto.

    1978-01-01

    An unknown ninhydrin positive peak on the chromatograms of amino acid analyzer of alkalified rumen fluid distillate of goats was isolated as DNP-derivative and identified as methylamine. Under normal feeding condition, its concentration in the rumen ranged 0.1-3.9 mgN/100 ml of rumen fluid and the proportion of methylamine in total volatile base, or apparent ammonia, ranged 0.5-13% during post-feeding. When ammonium salt was administered into the rumen with hay-concentrate ration, these values were increased up to 8.1 mgN/100 ml and 25.8% respectively. Concentrations of ammonia and methylamine when aspartic acid or alanine was administered into the rumen in place of concentrate mixture (control) were not markedly different from the control. In the case of arginine, glutamic acid or glycine administration, these concentrations were depressed as compared to the control. There were no distinct differences in the concentration of methylamine between the faunated and unfaunated goats. 14 C from 14 C-chlorella protein hydrolyzates, U- 14 C-alanine, 2- 14 C-glycine or 14 C-sodium bicarbonate was incorporated into methylamine in invitro incubation with rumen micro-organisms. When the washed suspensions of rumen bacteria or protozoa were incubated with 14 C-chlorella protein hydrolyzates, the radioactivity in methylamine appeared only in the case of bacteria suspensions. After the addition of 15 N-ammonium citrate into the rumen, the incorporation of 15 N into methylamine was observed during 1-9 hr. (auth.)

  4. Biodegradation of hexachlorocyclohexane (HCH) by microorganisms.

    Science.gov (United States)

    Phillips, Theresa M; Seech, Alan G; Lee, Hung; Trevors, Jack T

    2005-08-01

    The organochlorine pesticide Lindane is the gamma-isomer of hexachlorocyclohexane (HCH). Technical grade Lindane contains a mixture of HCH isomers which include not only gamma-HCH, but also large amounts of predominantly alpha-, beta- and delta-HCH. The physical properties and persistence of each isomer differ because of the different chlorine atom orientations on each molecule (axial or equatorial). However, all four isomers are considered toxic and recalcitrant worldwide pollutants. Biodegradation of HCH has been studied in soil, slurry and culture media but very little information exists on in situ bioremediation of the different isomers including Lindane itself, at full scale. Several soil microorganisms capable of degrading, and utilizing HCH as a carbon source, have been reported. In selected bacterial strains, the genes encoding the enzymes involved in the initial degradation of Lindane have been cloned, sequenced, expressed and the gene products characterized. HCH is biodegradable under both oxic and anoxic conditions, although mineralization is generally observed only in oxic systems. As is found for most organic compounds, HCH degradation in soil occurs at moderate temperatures and at near neutral pH. HCH biodegradation in soil has been reported at both low and high (saturated) moisture contents. Soil texture and organic matter appear to influence degradation presumably by sorption mechanisms and impact on moisture retention, bacterial growth and pH. Most studies report on the biodegradation of relatively low (< 500 mg/kg) concentrations of HCH in soil. Information on the effects of inorganic nutrients, organic carbon sources or other soil amendments is scattered and inconclusive. More in-depth assessments of amendment effects and evaluation of bioremediation protocols, on a large scale, using soil with high HCH concentrations, are needed.

  5. Autecology of microorganisms of typical Ecuador biotopes.

    Science.gov (United States)

    Tashyrev, O B; Pidgorskyi, V S; Toro, Miguel Naranjo; Gualoto, Miguel; Gladka, G V; Tashyreva, H O; Rokitko, P V; Romanovskaya, V A

    2014-01-01

    34 strains of aerobic chemoorganotrophic microorganisms were isolated from 23 soil and plant samples selected from highland biotopes of Ecuador-Andes massif (Papallacta, 4020 m), ash at the foot of the volcano Tungurahua, mountainous jungle (La Favorita, 1600 m), as well as in humid tropic botanical garden (state Puyo, 950 m). In mountain jungle samples the high number of bacteria--10(5)-10(7) CFU/g of sample were represented by 2-5 morphotypes. In highland (4020 m) samples the bacterial counts made from 10(2) to 10(7) CFU/g of sample. The current study describes resistance of isolated strains to high salinity, UV radiation and toxic metal ions. The majority of isolated strains were halotolerant. Isolates from volcanic ash showed high resistance level to UV radiation--LD99,99 made 1000-1440 J/m2; resistance level for isolates from the soil of Puyo Botanical Garden and isolates from rock lichen (Papallacta) LD99,99 made 1160 and 800 J/m2 respectively. Strains isolated from mountain jungle (La Favorita) showed lower UV-resistance. In highland biotopes of Ecuador occurred bacteria resistant to toxic metal ions. The highest resistance to Hg2+ was shown by isolate of lichen from mountain jungle, the maximal growth concentration was 0.025 g/L; to Cr(VI)--by isolate from lichen rock massif--3,0 g/L. Correlation between metal-resistance, halotolerace and UV resistance for studied strains was not detected, probably because of different microbial cell damage/repair mechanisms under the action of these factors.

  6. Environmental assessment of the potential effects of aquifer thermal energy storage systems on microorganisms in groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Hicks, R.J.; Stewart, D.L.

    1988-03-01

    The primary objective of this study was to evaluate the potential environmental effects (both adverse and beneficials) of aquifer thermal energy storage (ATES) technology pertaining to microbial communities indigenous to subsurface environments (i.e., aquifers) and the propagation, movement, and potential release of pathogenic microorganisms (specifically, Legionella) within ATES systems. Seasonal storage of thermal energy in aquifers shows great promise to reduce peak demand; reduce electric utility load problems; contribute to establishing favorable economics for district heating and cooling systems; and reduce pollution from extraction, refining, and combustion of fossil fuels. However, concerns that the widespread implementation of this technology may have adverse effects on biological systems indigeneous to aquifers, as well as help to propagate and release pathogenic organisms that enter thee environments need to be resolved. 101 refs., 2 tabs.

  7. Controlled Release from Recombinant Polymers

    Science.gov (United States)

    Price, Robert; Poursaid, Azadeh; Ghandehari, Hamidreza

    2014-01-01

    Recombinant polymers provide a high degree of molecular definition for correlating structure with function in controlled release. The wide array of amino acids available as building blocks for these materials lend many advantages including biorecognition, biodegradability, potential biocompatibility, and control over mechanical properties among other attributes. Genetic engineering and DNA manipulation techniques enable the optimization of structure for precise control over spatial and temporal release. Unlike the majority of chemical synthetic strategies used, recombinant DNA technology has allowed for the production of monodisperse polymers with specifically defined sequences. Several classes of recombinant polymers have been used for controlled drug delivery. These include, but are not limited to, elastin-like, silk-like, and silk-elastinlike proteins, as well as emerging cationic polymers for gene delivery. In this article, progress and prospects of recombinant polymers used in controlled release will be reviewed. PMID:24956486

  8. Soil microorganisms determine the sorption of radionuclides within organic soil systems

    International Nuclear Information System (INIS)

    Parekh, N.R.; Poskitt, J.M.; Dodd, B.A.; Potter, E.D.; Sanchez, A.

    2008-01-01

    The potential of soil microorganisms to enhance the retention of 137 Cs and 85 Sr in organic systems was assessed in a series of experiments. A biologically active, 'mineral-free', organic material, produced under laboratory conditions from leaves, was used as the uptake matrix in all experiments to minimise potential interference from competing clay minerals. Biological uptake and release were differentiated from abiotic processes by comparing the sorption of radionuclides in sterilised organic material with sterile material inoculated with soil extracts or single fungal strains. Our results show conclusively that living components of soil systems are of primary importance in the uptake of radionuclides in organic material. The presence of soil microorganisms significantly enhanced the retention of Cs in organic systems and ∼70% of the Cs spike was strongly (irreversibly) bound (remained non-extractable) in the presence of microorganisms compared to only ∼10% in abiotic systems. Sorption of 85 Sr was not significantly influenced by the presence of soil microorganisms. A non-linear temperature response was observed for the retention in biotic systems with increased uptake at between 10 and 30 deg. C and lower retention at temperatures above or below the optimum range. The optimum temperatures for biological uptake were between 15 and 20 deg. C for Cs, and 25 and 30 deg. C for Sr. Our results indicate that single strains of soil and saprotrophic fungi make an important contribution to the sorption of Cs and Sr in organic systems, but can only account for part of the strong, irreversible binding observed in biotic systems. Single strains of soil fungi increased the amount of non-extractable 137 Cs (by ∼30%) and 85 Sr (by ∼20%) in the organic systems as compared to abiotic systems, but the major fraction of 137 Cs and 85 Sr sorbed in systems inoculated with saprotrophic fungi remained extractable

  9. Nitrogen acquisition by plants and microorganisms in a temperate grassland.

    Science.gov (United States)

    Liu, Qianyuan; Qiao, Na; Xu, Xingliang; Xin, Xiaoping; Han, Jessie Yc; Tian, Yuqiang; Ouyang, Hua; Kuzyakov, Yakov

    2016-03-10

    Nitrogen (N) limitation is common in most terrestrial ecosystems, often leading to strong competition between microorganisms and plants. The mechanisms of niche differentiation to reduce this competition remain unclear. Short-term (15)N experiments with NH4(+), NO3(-), and glycine were conducted in July, August and September in a temperate grassland to evaluate the chemical, spatial and temporal niche differentiation by competition between plants and microorganisms for N. Microorganisms preferred NH4(+) and NO3(-), while plants preferred NO3(-). Both plants and microorganisms acquired more N in August and September than in July. The soil depth had no significant effects on microbial uptake, but significantly affected plant N uptake. Plants acquired 67% of their N from the 0-5 cm soil layer and 33% from the 5-15 cm layer. The amount of N taken up by microorganisms was at least seven times than plants. Although microorganisms efficiently compete for N with plants, the competition is alleviated through chemical partitioning mainly in deeper soil layer. In the upper soil layer, neither chemical nor temporal niche separation is realized leading to strong competition between plants and microorganisms that modifies N dynamics in grasslands.

  10. Isolation and characterization of Arctic microorganisms decomposing bioplastics.

    Science.gov (United States)

    Urbanek, Aneta K; Rymowicz, Waldemar; Strzelecki, Mateusz C; Kociuba, Waldemar; Franczak, Łukasz; Mirończuk, Aleksandra M

    2017-12-01

    The increasing amount of plastic waste causes significant environmental pollution. In this study, screening of Arctic microorganisms which are able to degrade bioplastics was performed. In total, 313 microorganisms were isolated from 52 soil samples from the Arctic region (Spitsbergen). Among the isolated microorganisms, 121 (38.66%) showed biodegradation activity. The ability of clear zone formation on emulsified poly(butylene succinate-co-adipate) (PBSA) was observed for 116 microorganisms (95.87%), on poly(butylene succinate) (PBS) for 73 microorganisms (60.33%), and on poly(ɛ-caprolactone) (PCL) for 102 microorganisms (84.3%). Moreover, the growth of microorganisms on poly(lactic acid) (PLA) agar plates was observed for 56 microorganisms (46.28%). Based on the 16S rRNA sequence, 10 bacterial strains which showed the highest ability for biodegradation were identified as species belonging to Pseudomonas sp. and Rhodococcus sp. The isolated fungal strains were tested for polycaprolactone films and commercial corn and potato starch bags degradation under laboratory conditions. Strains 16G (based on the analysis of a partial 18S rRNA sequence, identified as Clonostachys rosea) and 16H (identified as Trichoderma sp.) showed the highest capability for biodegradation. A particularly high capability for biodegradation was observed for the strain Clonostachys rosea, which showed 100% degradation of starch films and 52.91% degradation of PCL films in a 30-day shake flask experiment. The main advantage of the microorganisms isolated from Arctic environment is the ability to grow at low temperature and efficient biodegradation under this condition. The data suggest that C. rosea can be used in natural and laboratory conditions for degradations of bioplastics.

  11. Fate of indicator microorganisms under nutrient management plan conditions.

    Science.gov (United States)

    Bradford, Scott A; Segal, Eran

    2009-01-01

    Nutrient management plans (NMPs) for application of wastewater from concentrated animal feeding operations are designed to meet crop water and nutrient requirements, but implicitly assume that pathogenic microorganisms in the wastewater will be retained and die-off in the root zone. A NMP was implemented on a field plot to test this assumption by monitoring the fate of several fecal indicator microorganisms (Enterococcus, fecal coliforms, somatic coliphage, and total Escherichia coli). When well-water and wastewater were applied to meet measured evapotranspiration (ET), little advective transport of the indicator microorganisms occurred below the root zone and the remaining microorganisms rapidly died-off (within 1 mo). Additional experiments were conducted in the laboratory to better quantify microorganism transport and survival in the field soil. Batch survival experiments revealed much more rapid die-off rates for the bacterial indicator microorganisms in native than in sterilized soil, suggesting that biotic factors controlled survival. Saturated column experiments with packed field soil, demonstrated much greater transport potential for somatic coliphage than bacterial indicators (Enterococcus and total E. coli) and that the retention rates for the indicator microorganisms were not log-linear with depth. A worst case transport scenario of ponded infiltration on a large undistributed soil column from the field was also initiated and indicator microorganisms were not detected in the column outflow or in the soil at a depth of 65 cm. All of these observations support the hypothesis that a NMP at this site will protect groundwater supplies from microorganism contamination, especially when applied water and wastewater meet ET.

  12. Cotransport of microorganisms and metallic colloids in quartz sand or iron oxide-coated sand under real site hydrogeological conditions

    Science.gov (United States)

    Yu, Tong; Wen, Yujuan; Yang, Xinyao; Yang, Yuesuo

    2017-04-01

    The need for studying the fate and transport of engineered and naturally-occurring nanoparticles is of great concern in the past decade. Wudalianchi scenic spot as a famous International Geological Park has the biggest cold spring in China, which is also one of the three biggest cold spring in the world, with a history of over 200 years using in drinking and medical purpose. Thousands of tourists all over the world travelling here each year to enjoy the high quality mineral water and take a bath in the cold spring and "mud-bath" with special medication purposes. Recreation activities gave rise to the engineered nanomaterials (ENMs) releasing into the water environment and increase the risk of contamination. Therefore, it is necessary to evaluate the effect of ENMs-exposure in natural environment and how it influences the transport of microorganisms of Wudalianchi in/without the presence of natural colloids (humic acid) under a series of ion strength. A thorough critical literature review of both work in the study site and the bio/nano-particle transport in porous media was a kick-off of the study. With support of the site investigations and sampling of groundwater, surface water and surface mud/soils, further numerical modelling of the hydrogeochemical speciation of the groundwater was carried out, indicating comprehensive water-rock interactions of this particular region. Metallic nanoparticles (MNPs), including metals, metal oxides and other metal-containing nanoparticles, are produced and ubiquitously applied to medical, cosmetic, photonics and catalysis industries, etc. TiO2, a widely used raw material for cosmetic industries (e.g., sunscreens), was used in this study to represent MNPs. The microorganisms used in this study were extracted from the soil in Wudalianchi. Humic acid (HA), a key component of dissolved organic matter (DOM) chosen as the natural colloids in this study, are ubiquitous and significant constituents in soils and water environment that

  13. Antimicrobial Compounds from Marine Invertebrates-Derived Microorganisms.

    Science.gov (United States)

    Liu, Juan; Jung, Jee H; Liu, Yonghong

    2016-01-01

    It is known that marine invertebrates, including sponges, tunicates, cnidaria or mollusks, host affluent and various communities of symbiotic microorganisms. The microorganisms associated with the invertebrates metabolized various biologically active compounds, which could be an important resource for the discovery and development of potentially novel drugs. In this review, the new compounds with antimicrobial activity isolated from marine invertebrate-derived microorganisms in the last decade (2004-2014) will be presented, with focus on the relevant antimicrobial activities, origin of isolation, and information of strain species. New compounds without antimicrobial activity were not revealed.

  14. Influence of microorganisms on the alteration of glasses

    International Nuclear Information System (INIS)

    Besnainou, B.; Libert, M.F.

    1997-01-01

    Under specific conditions, microorganisms may enhance the alteration process of basaltic glass. However bacterial activity in the near field of a glass container would be possible only in environmental conditions provide nutrients and energetic substrates for bacterial growth. Depending of these conditions, microorganisms can: - modify the pH or the medium, - consume or produce soluble organic acids. To qualify the long term behaviour of glass, in presence of microorganisms, a qualitative and quantitative estimation of microbial activity potentialities and their consequences is needed. This must be achieved in studying the availability of the chemical species in the environment. (authors)

  15. Bio-recovery of non-essential heavy metals by intra- and extracellular mechanisms in free-living microorganisms.

    Science.gov (United States)

    García-García, Jorge D; Sánchez-Thomas, Rosina; Moreno-Sánchez, Rafael

    2016-01-01

    Free-living microorganisms may become suitable models for recovery of non-essential and essential heavy metals from wastewater bodies and soils by using and enhancing their accumulating and/or leaching abilities. This review analyzes the variety of different mechanisms developed mainly in bacteria, protists and microalgae to accumulate heavy metals, being the most relevant those involving phytochelatin and metallothionein biosyntheses; phosphate/polyphosphate metabolism; compartmentalization of heavy metal-complexes into vacuoles, chloroplasts and mitochondria; and secretion of malate and other organic acids. Cyanide biosynthesis for extra-cellular heavy metal bioleaching is also examined. These metabolic/cellular processes are herein analyzed at the transcriptional, kinetic and metabolic levels to provide mechanistic basis for developing genetically engineered microorganisms with greater capacities and efficiencies for heavy metal recovery, recycling of heavy metals, biosensing of metal ions, and engineering of metalloenzymes. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. News/Press Releases

    Data.gov (United States)

    Office of Personnel Management — A press release, news release, media release, press statement is written communication directed at members of the news media for the purpose of announcing programs...

  17. Micro-organisms and divers exposure to radioactivity in spent fuel pools at nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Muniz de A, D. [Underwater Construction Corporation, Latin America, Fortaleza, Ceara (Brazil); Silva, R. [Universidade Federal do Rio de Janeiro, Instituto de Biofisica Carlos Chagas Filho, 21941-902 Rio de Janeiro (Brazil); Gomes N, C. A., E-mail: dmuniz@uccdive.com [Universidade Federal do Rio de Janeiro, Instituto de Biologia, Environmental Engineering Program, 21941-902 Rio de Janeiro (Brazil)

    2017-09-15

    Many nuclear power plants (NPPs) around the world are in the process of extending their lifespan from 40 to 60 years of operation. The NPP; Angra 1 (Brazil) has performed a thorough evaluation of its Life Extension Engineering project. In this context, the spent fuel pool (SFP) was one of the areas studied in order to demonstrate the plants integrity for a life extension. Micro-organisms growing on the liner of the fuel transfer channel (Ftc) and SFP can form a film of bacteria, which is highly resistant to radiation. This paper aims to compare the micro-organisms found in NPP Angra 1 with those reported to other NPPs and also relates their occurrence with the radiation levels at the sites. It also compares divers exposure to radioactivity during underwater activities in the SFP. Fourteen samples were collected on the surface of the liners of the Ftc, the SFP and the drains within the fuel building (FB) of Angra 1. For the identification of the micro-organisms, a metagenomics analysis was performed by random sequencing (Shotgun) and the use of Ion Torrent PGM Sequence r. Twelve micro-organisms phyla were identified; Acido-bacteria, Actino-bacteria, Bacteroidetes, Chlamydiae, Chlorobi, Chloroflexi, Cyano-bacteria, Deinococcus-Thermus, Firmicutes, Planctomycetes, Proteo-bacteria, and Verrucomicrobia as well as organisms not classified. In the SFP of Angra 1, the bacteria survived the exposure to a radiation of 0.416 Gy/h (high radiation). Deinococcus-thermus, bacteria identified in Angra 1, has resisted an exposure to 30,000 Gy/h in another plant. (Author)

  18. Micro-organisms and divers exposure to radioactivity in spent fuel pools at nuclear power plants

    International Nuclear Information System (INIS)

    Muniz de A, D.; Silva, R.; Gomes N, C. A.

    2017-09-01

    Many nuclear power plants (NPPs) around the world are in the process of extending their lifespan from 40 to 60 years of operation. The NPP; Angra 1 (Brazil) has performed a thorough evaluation of its Life Extension Engineering project. In this context, the spent fuel pool (SFP) was one of the areas studied in order to demonstrate the plants integrity for a life extension. Micro-organisms growing on the liner of the fuel transfer channel (Ftc) and SFP can form a film of bacteria, which is highly resistant to radiation. This paper aims to compare the micro-organisms found in NPP Angra 1 with those reported to other NPPs and also relates their occurrence with the radiation levels at the sites. It also compares divers exposure to radioactivity during underwater activities in the SFP. Fourteen samples were collected on the surface of the liners of the Ftc, the SFP and the drains within the fuel building (FB) of Angra 1. For the identification of the micro-organisms, a metagenomics analysis was performed by random sequencing (Shotgun) and the use of Ion Torrent PGM Sequence r. Twelve micro-organisms phyla were identified; Acido-bacteria, Actino-bacteria, Bacteroidetes, Chlamydiae, Chlorobi, Chloroflexi, Cyano-bacteria, Deinococcus-Thermus, Firmicutes, Planctomycetes, Proteo-bacteria, and Verrucomicrobia as well as organisms not classified. In the SFP of Angra 1, the bacteria survived the exposure to a radiation of 0.416 Gy/h (high radiation). Deinococcus-thermus, bacteria identified in Angra 1, has resisted an exposure to 30,000 Gy/h in another plant. (Author)

  19. Antibiotic cytotoxic effects of microorganisms isolated from Jachymov uranium mines

    International Nuclear Information System (INIS)

    Fuska, J.; Fuskova, A.

    1982-01-01

    Microorganisms were isolated from old relinquished uranium mines in Jachymov; they had been growing for several decades in darkness in temperatures of 5 to 12 degC and relative humidity from 80 to 100%. The concentration of uranium salts in mine waters varied from 10 -4 to 10 -5 g.l -1 , that of Rn in the atmosphere was from 0.04 to 40 Bq.l -1 . Of 324 cultures, 18.8% inhibited the growth of Bacillus subtilis, Escherichia coli and Candida pseudotropicalis and 16.6% that of HeLa cells. The frequency of microorganisms inhibiting the growth of HeLa or Ehrlich ascites cells was markedly higher in this set of cultures than among microorganisms kept in culture collections or isolated from other natural habitats. About 10% of the isolated cultures were mycelia sterilia. The following antibiotics were isolated from microorganisms obtained from uranium mines: frequentin, vermiculin, vermicillin, vermistatin, cytostipin and duclauxin. (author)

  20. High throughput screening method for assessing heterogeneity of microorganisms

    NARCIS (Netherlands)

    Ingham, C.J.; Sprenkels, A.J.; van Hylckama Vlieg, J.E.T.; Bomer, Johan G.; de Vos, W.M.; van den Berg, Albert

    2006-01-01

    The invention relates to the field of microbiology. Provided is a method which is particularly powerful for High Throughput Screening (HTS) purposes. More specific a high throughput method for determining heterogeneity or interactions of microorganisms is provided.

  1. SELECTION OF MICROORGANISMS FOR FERMENTATION OF MEAT MATERIALS

    Directory of Open Access Journals (Sweden)

    Danylenko S. G.

    2014-08-01

    Full Text Available Principal criteria for the selection of microorganisms with a wide range of biological and technological properties for fermentation of raw meats are considered. Attention is paid to the main groups of microorganisms such as Micrococсus, Staphylococcus, Lactobacillus, Bifidobacterium and Propionibacterium which are promising for creation of bacterial preparations. To create bacterial preparations, the basic criteria of selection for microorganisms were determined as follows: the ability of microorganisms to be developed within the specific ecological niche (raw meat materials and their influence on flavor characteristics of the final product under the conditions of intensification of production technologies of meat products. Methods used for search and retrieval of technologically promising strains from different natural sources (fresh meats, minced meats, meat, dairy and sour-milk products, vegetables, fruit, brines and mixtures for salting are considered.

  2. Establishing Drug Resistance in Microorganisms by Mass Spectrometry

    Science.gov (United States)

    Demirev, Plamen A.; Hagan, Nathan S.; Antoine, Miquel D.; Lin, Jeffrey S.; Feldman, Andrew B.

    2013-08-01

    A rapid method to determine drug resistance in bacteria based on mass spectrometry is presented. In it, a mass spectrum of an intact microorganism grown in drug-containing stable isotope-labeled media is compared with a mass spectrum of the intact microorganism grown in non-labeled media without the drug present. Drug resistance is determined by predicting characteristic mass shifts of one or more microorganism biomarkers using bioinformatics algorithms. Observing such characteristic mass shifts indicates that the microorganism is viable even in the presence of the drug, thus incorporating the isotopic label into characteristic biomarker molecules. The performance of the method is illustrated on the example of intact E. coli, grown in control (unlabeled) and 13C-labeled media, and analyzed by MALDI TOF MS. Algorithms for data analysis are presented as well.

  3. Marine microorganisms as potential biofactories for synthesis of metallic nanoparticles.

    Science.gov (United States)

    Manivasagan, Panchanathan; Nam, Seung Yun; Oh, Junghwan

    2016-11-01

    The use of marine microorganisms as potential biofactories for green synthesis of metallic nanoparticles is a relatively new field of research with considerable prospects. This method is eco-friendly, time saving, and inexpensive and can be easily scaled up for large-scale synthesis. The increasing need to develop simple, nontoxic, clean, and environmentally safe production methods for nanoparticles and to decrease environmental impact, minimize waste, and increase energy productivity has become important in this field. Marine microorganisms are tiny organisms that live in marine ecosystems and account for >98% of biomass of the world's ocean. Marine microorganisms synthesize metallic nanoparticles either intracellularly or extracellularly. Marine microbially-produced metallic nanoparticles have received considerable attention in recent years because of their expected impact on various applications such as medicine, energy, electronic, and space industries. The present review discusses marine microorganisms as potential biofactories for the green synthesis of metallic nanoparticles and their potential applications.

  4. Anisotropic structures of some microorganisms studied by polarization microscopy

    Czech Academy of Sciences Publication Activity Database

    Žižka, Zdeněk

    2014-01-01

    Roč. 59, č. 5 (2014), s. 363-368 ISSN 0015-5632 Institutional support: RVO:61388971 Keywords : Polarization microscopy * microorganism Subject RIV: EE - Microbiology, Virology Impact factor: 1.000, year: 2014

  5. Diversity and adaptations of deep-sea microorganisms

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.

    -tolerant enzymes, natural products of potential use in human health management and environmental bioremediation using solvent-tolerant microorganisms are some of the potential biotechnological applications of these deep-sea microbes....

  6. A device for continuous microscopic examination of aquatic microorganisms

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, S.

    The device consists of a sealed microscopic mount provided with an inlet for liquid medium and an outlet, permitting continuous flow of the liquid. It permits observation of development of marine microorganisms such as thraustochytrids for 3 d...

  7. isolation and identification of the microorganisms most prevalent

    African Journals Online (AJOL)

    problems presenting in eye clinics on a daily basis. With one or two ... microorganisms most prevalent in external eye infections in Owerri urban (as seen Mercy Eye clinic). With the aid of sterile .... through personal contacts. Consequently, the.

  8. Multiorganismal insects: diversity and function of resident microorganisms.

    Science.gov (United States)

    Douglas, Angela E

    2015-01-07

    All insects are colonized by microorganisms on the insect exoskeleton, in the gut and hemocoel, and within insect cells. The insect microbiota is generally different from microorganisms in the external environment, including ingested food. Specifically, certain microbial taxa are favored by the conditions and resources in the insect habitat, by their tolerance of insect immunity, and by specific mechanisms for their transmission. The resident microorganisms can promote insect fitness by contributing to nutrition, especially by providing essential amino acids, B vitamins, and, for fungal partners, sterols. Some microorganisms protect their insect hosts against pathogens, parasitoids, and other parasites by synthesizing specific toxins or modifying the insect immune system. Priorities for future research include elucidation of microbial contributions to detoxification, especially of plant allelochemicals in phytophagous insects, and resistance to pathogens; as well as their role in among-insect communication; and the potential value of manipulation of the microbiota to control insect pests.

  9. Isolation and screening of microorganisms from a gari fermentation ...

    African Journals Online (AJOL)

    Isolation and screening of microorganisms from a gari fermentation process for starter culture development. Vinodh A Edward, Moutairou Egounlety, Melanie Huch, Petrus J Van Zyl, Suren Singh, Naledzani D Nesengani, Vetja M Haakuria, Charles MAP Franz ...

  10. Isolation of microorganisms for biological control the moniliophthora roreri

    OpenAIRE

    suarez contreras, liliana yanet; Rangel Riaño, Alba Luz

    2014-01-01

    Moniliophlhora roreri is the causal agent of cocoa Moniliasis, which produces losses of up to 60% of the crop, as it affects only its commercial product, the cob. Biological control appears as an alternative management, using endophytic microorganisms. The reason because of this research came up was that it was aimed to isolate microorganisms with antagonist potential for biological control towards the phytopathogen M. roreri in Norte de Santander. This is done through isolation and identifica...

  11. Microorganisms having enhanced tolerance to inhibitors and stress

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Steven D.; Yang, Shihui

    2014-07-29

    The present invention provides genetically modified strains of microorganisms that display enhanced tolerance to stress and/or inhibitors such as sodium acetate and vanillin. The enhanced tolerance can be achieved by increasing the expression of a protein of the Sm-like superfamily such as a bacterial Hfq protein and a fungal Sm or Lsm protein. Further, the present invention provides methods of producing alcohol from biomass materials by using the genetically modified microorganisms of the present invention.

  12. Microorganisms -indicators of the level of soil pollution with lead

    OpenAIRE

    Stavreva Veselinovska, Snezana

    2011-01-01

    Environmental pollution with heavy metals present a real threat to wildlife because the metals cannot be naturally decomposed as is the case with organic pollutants, and as such they can survive in the environment while accumulating the heavy metals in different parts. Pollution with metals can affect different organisms in the environment, such as microorganisms, plants and animals, but the degree of toxicity depends on the species. Microorganisms have different mechanisms of coping with...

  13. The microorganisms as a renewable source of ecological clean fuel

    International Nuclear Information System (INIS)

    Shalygo, N.V.; Mel'nikov, S.S.; Manankina, E.E.; Budakova, E.A.; Kolyago, V.M.

    2006-01-01

    Five families of microorganisms (Bacillaceae, Rhodospirillaceae, Cyanophyceae, Chlorophyceae and Euglenophyceae) as hydrogen producers were tested and the conditions that are necessary for hydrogen photoproduction were investigated. It was shown, that the most effective producers of hydrogen were Rhodobacter spheroides, Clostridium sp.; Euglena gracilis var. bacillaris and Chlamydomonas reinhardtii. Addition of glucose, iron and vanadium salts resulted in the increase of hydrogen production. Polycultures consisted of two or three microorganisms were more effective hydrogen producers compared to separate monocultures. (authors)

  14. Method for treating wastewater using microorganisms and vascular aquatic plants

    Science.gov (United States)

    Wolverton, B. C. (Inventor)

    1983-01-01

    A method for treating wastewater compresses subjecting the wastewater to an anaerobic setting step for at least 6 hours and passing the liquid effluent from the anaerobic settling step through a filter cell in an upflow manner. There the effluent is subjected first to the action of anaerobic and facultative microorganisms, and then to the action of aerobic microorganisms and the roots of at least one vascular aquatic plant.

  15. Swimming of Microorganisms Viewed from String and Membrane Theories

    OpenAIRE

    Kawamura, Masako; Sugamoto, Akio; Nojiri, Shin'ichi

    1993-01-01

    Swimming of microorganisms is studied from a viewpoint of extended objects (strings and membranes) swimming in the incompressible f luid of low Reynolds number. The flagellated motion is analyzed in two dimensional fluid, by using the method developed in the ciliated motion with the Joukowski transformation. Discussion is given on the conserved charges and the algebra which are associated with the area (volume)- preserving diffeomorphisms giving the swimming motion of microorganisms. It is al...

  16. Evolution, Metabolism and Biotechnological Usage of Methylotrophic Microorganisms

    OpenAIRE

    Oleg Mosin; Ignat Ignatov

    2014-01-01

    Methylotrophs – aerobic chemoheterotrophic microorganisms submitted by cocci and bacilli mobile forms, are inhabitants of reservoirs and soils of various type, where there are going on various processes of decomposition of organic substances with formation of the one-carbon С1-compounds and some С2-, and С3-compounds, capable to be assimilated by methylotrophs. These microorganisms assimilating carbon on ribuloso-5-monophospate and serine pathways, are allocated from soil ground, the sewage c...

  17. [PERSPECTIVES OF DEVELOPMENT OF LIVE RECOMBINANT ANTHRAX VACCINES BASED ON OPPORTUNISTIC AND APATHOGENIC MICROORGANISMS].

    Science.gov (United States)

    Popova, P Yu; Mikshis, N I

    2016-01-01

    Live genetic engineering anthrax vaccines on the platform of avirulent and probiotic micro-organisms are a safe and adequate alternative to preparations based on attenuated Bacillus anthracis strains. Mucosal application results in a direct contact of the vaccine preparations with mucous membranes in those organs arid tissues of the macro-organisms, that are exposed to the pathogen in the first place, resulting in a development of local and systemic immune response. Live recombinant anthrax vaccines could be used both separately as well as in a prime-boost immunization scheme. The review focuses on immunogenic and protective properties of experimental live genetic engineering prearations, created based on members of geni of Salmonella, Lactobacillus and adenoviruses.

  18. Physiologically anaerobic microorganisms of the deep subsurface

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, S.E. Jr.; Chung, K.T.

    1992-06-01

    A variety of different media were used to isolate facultatively (FAB) and obligately anaerobic bacteria (OAB). These bacteria were isolated from core subsamples obtained from boreholes at the Idaho National Engineering Lab. (INEL) or at the Hanford Lab. (Yakima). Core material was sampled at various depths to 600 feet below the surface. All core samples with culturable bacteria contained at least FAB making thisthe most common physiological type of anaerobic bacteria present in the deep subsurface at these two sites. INEL core samples are characterized by isolates of both FAB and OAB. No isolates of acetogenic, methanogenic, or sulfate reducing bacteria were obtained. Yakima core samples are characterized by a marked predominance of FAB in comparison to OAB. In addition, isolates of acetogenic, methanogenic, and sulfate reducing bacteria were obtained. The Yakima site has the potential for complete anaerobic mineralization of organic compounds whereas this potential appears to be lacking at INEL.

  19. Volatilization of Po by microorganisms at laboratory culture experiments

    International Nuclear Information System (INIS)

    Momoshima, N.; Ishida, A.; Yoshinaga, C.; Fukuda, A.

    2005-01-01

    The previous experiments proved the volatility of polonium form culture medium in which microorganisms were propagated from seed of seawater, river water or pond water, therefore we did not know what kind of species are responsible to Po volatility. To search microorganisms, which concerned with Po emission we carried out culture experiments using known microorganisms. Three microorganisms were examined; Escherichia coli K-12, Bacillus subtilis and Chromobacterium violaceum. The microorganisms were pre-cultured in LB medium at 30 degree C and a small portion of the pre-cultured was transferred to a culture bottle in which LB medium and 208 Po tracer were contained. The culture was done at 30 degree C with shaking the culture bottle and air passed through a filter was introduced. The Po volatilized was transferred into the trap vials in which scintillator for liquid scintillation counting (LSC) was contained. The Po activity was measured by LSC. All of the microorganisms examined volatilized Po but their ability was quite different each other. Highest ability was observed on Chromobacterium violaceum and then Escherichia coli K-12 followed by Bacillus subtilis, the relative magnitude of the ability was 10 2 , 10, 1, respectively. Chromobacterium violaceum and Escherichia coli K-12 showed high volatility for the first 24 h but Escherichia coli K-12 showed a decrease thereafter. However high volatility was continued on Chromobacterium violaceum during the culture. The low culture temperature suppressed Po volatility, supporting biologically mediated Po emission from the culture.

  20. Synergistic interface behavior of strontium adsorption using mixed microorganisms.

    Science.gov (United States)

    Hu, Wenyuan; Dong, Faqin; Yang, Guangmin; Peng, Xin; Huang, Xiaojun; Liu, Mingxue; Zhang, Jing

    2017-08-10

    The proper handling of low-level radioactive waste is crucial to promote the sustainable development of nuclear power. Research into the mechanism for interactions between bacterium and radionuclides is the starting point for achieving successful remediation of radionuclides with microorganisms. Using Sr(II) as a simulation radionuclide and the mixed microorganisms of Saccharomyces cerevisiae and Bacillus subtilis as the biological adsorbent, this study investigates behavior at the interface between Sr(II) and the microorganisms as well as the mechanisms governing that behavior. The results show that the optimal ratio of mixed microorganisms is S. cerevisiae 2.0 g L -1 to B. subtilis 0.05 g L -1 , and the optimal pH is about 6.3. Sr(II) biosorption onto the mixed microorganisms is spontaneous and endothermic in nature. The kinetics and the equilibrium isotherm data of the biosorption process can be described with pseudo-second-order equation and the Langmuir isotherm equation, respectively. The key interaction between the biological adsorbent and Sr(II) involves shared electronic pairs arising from chemical reactions via bond complexation or electronic exchange, and spectral and energy spectrum analysis show that functional groups (e.g., hydroxyl, carboxyl, amino, amide) at the interface between the radionuclide and the mixed microorganisms are the main active sites of the interface reactions.

  1. Engineering Encounters: Engineering Adaptations

    Science.gov (United States)

    Gatling, Anne; Vaughn, Meredith Houle

    2015-01-01

    Engineering is not a subject that has historically been taught in elementary schools, but with the emphasis on engineering in the "Next Generation Science Standards," curricula are being developed to explicitly teach engineering content and design. However, many of the scientific investigations already conducted with students have…

  2. Microbial transformations of radionuclides released from nuclear fuel reprocessing plants

    International Nuclear Information System (INIS)

    Francis, A.J.

    2007-01-01

    Microorganisms can affect the stability and mobility of the actinides U, Pu, Cm, Am, Np, and the fission products Tc, I, Cs, Sr, released from nuclear fuel reprocessing plants. Under appropriate conditions, microorganisms can alter the chemical speciation, solubility and sorption properties and thus could increase or decrease the concentrations of radionuclides in solution and the bioavailability. Dissolution or immobilization of radionuclides is brought about by direct enzymatic action or indirect non-enzymatic action of microorganisms. Although the physical, chemical, and geochemical processes affecting dissolution, precipitation, and mobilization of radionuclides have been investigated, we have only limited information on the effects of microbial processes. The mechanisms of microbial transformations of the major and minor actinides and the fission products under aerobic and anaerobic conditions in the presence of electron donors and acceptors are reviewed. (author)

  3. Compost supplementation with nutrients and microorganisms in composting process.

    Science.gov (United States)

    Sánchez, Óscar J; Ospina, Diego A; Montoya, Sandra

    2017-11-01

    The composting is an aerobic, microorganism-mediated, solid-state fermentation process by which different organic materials are transformed into more stable compounds. The product obtained is the compost, which contributes to the improvement of physical, chemical and microbiological properties of the soil. However, the compost usage in agriculture is constrained because of its long-time action and reduced supply of nutrients to the crops. To enhance the content of nutrients assimilable by the plants in the compost, its supplementation with nutrients and inoculation with microorganisms have been proposed. The objective of this work was to review the state of the art on compost supplementation with nutrients and the role played by the microorganisms involved (or added) in their transformation during the composting process. The phases of composting are briefly compiled and different strategies for supplementation are analyzed. The utilization of nitrogenous materials and addition of microorganisms fixing nitrogen from the atmosphere or oxidizing ammonia into more assimilable for plants nitrogenous forms are analyzed. Several strategies for nitrogen conservation during composting are presented as well. The supplementation with phosphorus and utilization of microorganisms solubilizing phosphorus and potassium are also discussed. Main groups of microorganisms relevant during the composting process are described as well as most important strategies to identify them. In general, the development of this type of nutrient-enriched bio-inputs requires research and development not only in the supplementation of compost itself, but also in the isolation and identification of microorganisms and genes allowing the degradation and conversion of nitrogenous substances and materials containing potassium and phosphorus present in the feedstocks undergoing the composting process. In this sense, most important research trends and strategies to increase nutrient content in the compost

  4. Inhibition of Streptococcus mutans NS adhesion to glass with and without a salivary conditioning film by biosurfactant-releasing Streptococcus mitis strains

    NARCIS (Netherlands)

    van Hoogmoed, CG; van der Kuijl-Booij, M; van der Mei, HC; Busscher, HJ

    The release of biosurfactants by adhering microorganisms as a defense mechanism against other colonizing strains on the same substratum surface has been described previously for probiotic bacteria in the urogenital tract, the intestines, and the oropharynx but not for microorganisms in the oral

  5. [Relationships between air conditioning, airborne microorganisms and health].

    Science.gov (United States)

    Parat, S; Perdrix, A; Baconnier, P

    1999-01-01

    Concurrently with the increase of air-conditioning, potentially severe or frequent new diseases have emerged, giving rise to social and economical consequences. The first part of this work is a state of the art review of the relationships between air-conditioning, airborne microorganisms and health, through a technical, metrological and medical approach. The second part presents four studies performed in this field. Two of them deal with the relationship between airborne microorganisms and technical features of air-conditioning. Measurements performed on actual sites demonstrated the benefit of using high efficiency filters and low risk components in air-conditioning systems. The third study was aimed to look for a relationship between airborne microorganisms and sick building syndrome symptoms. Statistical analyses of individual data revealed significant associations between airborne bacteria or fungi and symptoms. These results may be the first step in determining a dose-response relationship, in order to define threshold limit values in this field. In the fourth study, the contribution of particle counting in assessing exposure to airborne microorganisms was explored by monitoring simultaneous variations of microbial and particle concentrations. The results showed that associating particle counting may allow to detect microbial variations instantaneously, and therefore improve the assessment of exposure to airborne microorganisms.

  6. Assessment of cellulolytic microorganisms in soils of Nevados Park, Colombia.

    Science.gov (United States)

    Avellaneda-Torres, Lizeth Manuela; Pulido, Claudia Patricia Guevara; Rojas, Esperanza Torres

    2014-01-01

    A systematized survey was conducted to find soil-borne microbes that degrade cellulose in soils from unique ecosystems, such as the Superpáramo, Páramo, and the High Andean Forest in the Nevados National Natural Park (NNNP), Colombia. These high mountain ecosystems represent extreme environments, such as high levels of solar radiation, low atmospheric pressure, and extreme daily changes in temperature. Cellulolytic activity of the microorganisms was evaluated using qualitative tests, such as growth in selective media followed by staining with congo red and iodine, and quantitative tests to determine the activity of endoglucanase, β-glucosidase, exoglucanase, and total cellulase. Microorganisms were identified using molecular markers, such as the 16S rRNA gene for bacteria and the internal transcribed spacer region (ITS) of ribosomal DNA for fungi. Multivariate statistical analysis (MVA) was used to select microorganisms with high cellulolytic capacity. A total of 108 microorganisms were isolated from the soils and, in general, the enzymatic activities of fungi were higher than those of bacteria. Our results also found that none of the organisms studied were able to degrade all the components of the cellulose and it is therefore suggested that a combination of bacteria and/or fungi with various enzymatic activities be used to obtain high total cellulolytic activity. This study gives an overview of the potential microorganism that could be used for cellulose degradation in various biotechnological applications and for sustainable agricultural waste treatment.

  7. Assessment of cellulolytic microorganisms in soils of Nevados Park, Colombia

    Directory of Open Access Journals (Sweden)

    Lizeth Manuela Avellaneda-Torres

    2014-12-01

    Full Text Available A systematized survey was conducted to find soil-borne microbes that degrade cellulose in soils from unique ecosystems, such as the Superpáramo, Páramo, and the High Andean Forest in the Nevados National Natural Park (NNNP, Colombia. These high mountain ecosystems represent extreme environments, such as high levels of solar radiation, low atmospheric pressure, and extreme daily changes in temperature. Cellulolytic activity of the microorganisms was evaluated using qualitative tests, such as growth in selective media followed by staining with congo red and iodine, and quantitative tests to determine the activity of endoglucanase, β-glucosidase, exoglucanase, and total cellulase. Microorganisms were identified using molecular markers, such as the 16S rRNA gene for bacteria and the internal transcribed spacer region (ITS of ribosomal DNA for fungi. Multivariate statistical analysis (MVA was used to select microorganisms with high cellulolytic capacity. A total of 108 microorganisms were isolated from the soils and, in general, the enzymatic activities of fungi were higher than those of bacteria. Our results also found that none of the organisms studied were able to degrade all the components of the cellulose and it is therefore suggested that a combination of bacteria and/or fungi with various enzymatic activities be used to obtain high total cellulolytic activity. This study gives an overview of the potential microorganism that could be used for cellulose degradation in various biotechnological applications and for sustainable agricultural waste treatment.

  8. Biosurfactants Produced by Marine Microorganisms with Therapeutic Applications.

    Science.gov (United States)

    Gudiña, Eduardo J; Teixeira, José A; Rodrigues, Lígia R

    2016-02-18

    Marine microorganisms possess unique metabolic and physiological features and are an important source of new biomolecules, such as biosurfactants. Some of these surface-active compounds synthesized by marine microorganisms exhibit antimicrobial, anti-adhesive and anti-biofilm activity against a broad spectrum of human pathogens (including multi-drug resistant pathogens), and could be used instead of existing drugs to treat infections caused by them. In other cases, these biosurfactants show anti-cancer activity, which could be envisaged as an alternative to conventional therapies. However, marine biosurfactants have not been widely explored, mainly due to the difficulties associated with the isolation and growth of their producing microorganisms. Culture-independent techniques (metagenomics) constitute a promising approach to study the genetic resources of otherwise inaccessible marine microorganisms without the requirement of culturing them, and can contribute to the discovery of novel biosurfactants with significant biological activities. This paper reviews the most relevant biosurfactants produced by marine microorganisms with potential therapeutic applications and discusses future perspectives and opportunities to discover novel molecules from marine environments.

  9. Biosurfactants Produced by Marine Microorganisms with Therapeutic Applications

    Directory of Open Access Journals (Sweden)

    Eduardo J. Gudiña

    2016-02-01

    Full Text Available Marine microorganisms possess unique metabolic and physiological features and are an important source of new biomolecules, such as biosurfactants. Some of these surface-active compounds synthesized by marine microorganisms exhibit antimicrobial, anti-adhesive and anti-biofilm activity against a broad spectrum of human pathogens (including multi-drug resistant pathogens, and could be used instead of existing drugs to treat infections caused by them. In other cases, these biosurfactants show anti-cancer activity, which could be envisaged as an alternative to conventional therapies. However, marine biosurfactants have not been widely explored, mainly due to the difficulties associated with the isolation and growth of their producing microorganisms. Culture-independent techniques (metagenomics constitute a promising approach to study the genetic resources of otherwise inaccessible marine microorganisms without the requirement of culturing them, and can contribute to the discovery of novel biosurfactants with significant biological activities. This paper reviews the most relevant biosurfactants produced by marine microorganisms with potential therapeutic applications and discusses future perspectives and opportunities to discover novel molecules from marine environments.

  10. Cybernetic modeling of adaptive prediction of environmental changes by microorganisms.

    Science.gov (United States)

    Mandli, Aravinda R; Modak, Jayant M

    2014-02-01

    Microorganisms exhibit varied regulatory strategies such as direct regulation, symmetric anticipatory regulation, asymmetric anticipatory regulation, etc. Current mathematical modeling frameworks for the growth of microorganisms either do not incorporate regulation or assume that the microorganisms utilize the direct regulation strategy. In the present study, we extend the cybernetic modeling framework to account for asymmetric anticipatory regulation strategy. The extended model accurately captures various experimental observations. We use the developed model to explore the fitness advantage provided by the asymmetric anticipatory regulation strategy and observe that the optimal extent of asymmetric regulation depends on the selective pressure that the microorganisms experience. We also explore the importance of timing the response in anticipatory regulation and find that there is an optimal time, dependent on the extent of asymmetric regulation, at which microorganisms should respond anticipatorily to maximize their fitness. We then discuss the advantages offered by the cybernetic modeling framework over other modeling frameworks in modeling the asymmetric anticipatory regulation strategy. Copyright © 2013. Published by Elsevier Inc.

  11. Mini-review: Inhibition of biofouling by marine microorganisms.

    Science.gov (United States)

    Dobretsov, Sergey; Abed, Raeid M M; Teplitski, Max

    2013-01-01

    Any natural or artificial substratum exposed to seawater is quickly fouled by marine microorganisms and later by macrofouling species. Microfouling organisms on the surface of a substratum form heterogenic biofilms, which are composed of multiple species of heterotrophic bacteria, cyanobacteria, diatoms, protozoa and fungi. Biofilms on artificial structures create serious problems for industries worldwide, with effects including an increase in drag force and metal corrosion as well as a reduction in heat transfer efficiency. Additionally, microorganisms produce chemical compounds that may induce or inhibit settlement and growth of other fouling organisms. Since the last review by the first author on inhibition of biofouling by marine microbes in 2006, significant progress has been made in the field. Several antimicrobial, antialgal and antilarval compounds have been isolated from heterotrophic marine bacteria, cyanobacteria and fungi. Some of these compounds have multiple bioactivities. Microorganisms are able to disrupt biofilms by inhibition of bacterial signalling and production of enzymes that degrade bacterial signals and polymers. Epibiotic microorganisms associated with marine algae and invertebrates have a high antifouling (AF) potential, which can be used to solve biofouling problems in industry. However, more information about the production of AF compounds by marine microorganisms in situ and their mechanisms of action needs to be obtained. This review focuses on the AF activity of marine heterotrophic bacteria, cyanobacteria and fungi and covers publications from 2006 up to the end of 2012.

  12. Identification and Characterization of Extremophile Microorganisms with Significance to Astrobiology

    Science.gov (United States)

    Bej, Asim K.

    2003-01-01

    It is now well recognized that microorganisms thrive in extreme ecological conditions such as geothermal vents, polar region, acid and alkaline lakes, and the cold pressurized depth of the ocean floor of this planet. Morphological, physiological, biochemical and genetic adaptations to extreme environments by these extremophile microorganisms have generated immense interest amongst astrobiologists who increasingly believe in the existence of extraterrestrial life. The evidence collected by NASA's space probe Galileo suggested the presence of liquid water and volcanic activity on Mars and Jupiter's satellite Europa. Volcanic activity provides some of the heat necessary to keep the water on Europa from freezing that could provide important dissolved chemicals needed by living organisms. The possibility of the existence of hypersaline alkaline lakes and evaporites confined within closed volcanic basins and impact craters on Mars, and a layer of liquid water under the ice on Europa provide sufficient 'raison d'etre' to study microorganisms in similar extreme environments on Earth, which could provide us with a model that would help establish the existence of extraterrestrial life on other planetary bodies. The objectives of the summer research project were as follows: (1) application of molecular approaches to help establish new species of extremophile microorganisms isolated from a hypersaline alkaline lake; and (2) identification of a major cold-shock gene (cspA) homolog from a psychrotolerant microorganism, PmagG1.

  13. Effect of Nisin's Controlled Release on Microbial Growth as Modeled for Micrococcus luteus.

    Science.gov (United States)

    Balasubramanian, Aishwarya; Lee, Dong Sun; Chikindas, Michael L; Yam, Kit L

    2011-06-01

    The need for safe food products has motivated food scientists and industry to find novel technologies for antimicrobial delivery for improving food safety and quality. Controlled release packaging is a novel technology that uses the package to deliver antimicrobials in a controlled manner and sustain antimicrobial stress on the targeted microorganism over the required shelf life. This work studied the effect of controlled release of nisin to inhibit growth of Micrococcus luteus (a model microorganism) using a computerized syringe pump system to mimic the release of nisin from packaging films which was characterized by an initially fast rate and a slower rate as time progressed. The results show that controlled release of nisin was strikingly more effective than instantly added ("formulated") nisin. While instant addition experiments achieved microbial inhibition only at the beginning, controlled release experiments achieved complete microbial inhibition for a longer time, even when as little as 15% of the amount of nisin was used as compared to instant addition.

  14. Soil microorganisms alleviate the allelochemical effects of a thyme monoterpene on the performance of an associated grass species.

    Science.gov (United States)

    Ehlers, Bodil K

    2011-01-01

    Plant allelochemicals released into the soil can significantly impact the performance of associated plant species thereby affecting their competitive ability. Soil microbes can potentially affect the interaction between plant and plant chemicals by degrading the allelochemicals. However, most often plant-plant chemical interactions are studied using filter paper bioassays examining the pair-wise interaction between a plant and a plant chemical, not taking into account the potential role of soil microorganisms. To explore if the allelopathic effects on a grass by the common thyme monoterpene "carvacrol" are affected by soil microorganisms. Seedlings of the grass Agrostis capillaris originating from 3 different thyme sites were raised in the greenhouse. Seedlings were grown under four different soil treatments in a 2*2 fully factorial experiment. The monoterpene carvacrol was either added to standard greenhouse soil or left out, and soil was either sterilized (no soil microorganisms) or not (soil microorganisms present in soil). The presence of carvacrol in the soil strongly increased mortality of Agrostis plants, and this increase was highest on sterile soil. Plant biomass was reduced on soil amended with carvacrol, but only when the soil was also sterilized. Plants originating from sites where thyme produces essential oils containing mostly carvacrol had higher survival on soil treated with that monoterpene than plants originating from a site where thyme produced different types of terpenes, suggesting an adaptive response to the locally occurring terpene. The study shows that presence of soil microorganisms can alleviate the negative effect of a common thyme monoterpene on the performance of an associated plant species, emphasizing the role of soil microbes in modulating plant-plant chemical interactions.

  15. Soil microorganisms alleviate the allelochemical effects of a thyme monoterpene on the performance of an associated grass species.

    Directory of Open Access Journals (Sweden)

    Bodil K Ehlers

    Full Text Available Plant allelochemicals released into the soil can significantly impact the performance of associated plant species thereby affecting their competitive ability. Soil microbes can potentially affect the interaction between plant and plant chemicals by degrading the allelochemicals. However, most often plant-plant chemical interactions are studied using filter paper bioassays examining the pair-wise interaction between a plant and a plant chemical, not taking into account the potential role of soil microorganisms.To explore if the allelopathic effects on a grass by the common thyme monoterpene "carvacrol" are affected by soil microorganisms. Seedlings of the grass Agrostis capillaris originating from 3 different thyme sites were raised in the greenhouse. Seedlings were grown under four different soil treatments in a 2*2 fully factorial experiment. The monoterpene carvacrol was either added to standard greenhouse soil or left out, and soil was either sterilized (no soil microorganisms or not (soil microorganisms present in soil. The presence of carvacrol in the soil strongly increased mortality of Agrostis plants, and this increase was highest on sterile soil. Plant biomass was reduced on soil amended with carvacrol, but only when the soil was also sterilized. Plants originating from sites where thyme produces essential oils containing mostly carvacrol had higher survival on soil treated with that monoterpene than plants originating from a site where thyme produced different types of terpenes, suggesting an adaptive response to the locally occurring terpene.The study shows that presence of soil microorganisms can alleviate the negative effect of a common thyme monoterpene on the performance of an associated plant species, emphasizing the role of soil microbes in modulating plant-plant chemical interactions.

  16. Soil Microorganisms Alleviate the Allelochemical Effects of a Thyme Monoterpene on the Performance of an Associated Grass Species

    Science.gov (United States)

    Ehlers, Bodil K.

    2011-01-01

    Background Plant allelochemicals released into the soil can significantly impact the performance of associated plant species thereby affecting their competitive ability. Soil microbes can potentially affect the interaction between plant and plant chemicals by degrading the allelochemicals. However, most often plant-plant chemical interactions are studied using filter paper bioassays examining the pair-wise interaction between a plant and a plant chemical, not taking into account the potential role of soil microorganisms. Methodology/Principal findings To explore if the allelopathic effects on a grass by the common thyme monoterpene “carvacrol” are affected by soil microorganisms. Seedlings of the grass Agrostis capillaris originating from 3 different thyme sites were raised in the greenhouse. Seedlings were grown under four different soil treatments in a 2*2 fully factorial experiment. The monoterpene carvacrol was either added to standard greenhouse soil or left out, and soil was either sterilized (no soil microorganisms) or not (soil microorganisms present in soil). The presence of carvacrol in the soil strongly increased mortality of Agrostis plants, and this increase was highest on sterile soil. Plant biomass was reduced on soil amended with carvacrol, but only when the soil was also sterilized. Plants originating from sites where thyme produces essential oils containing mostly carvacrol had higher survival on soil treated with that monoterpene than plants originating from a site where thyme produced different types of terpenes, suggesting an adaptive response to the locally occurring terpene. Conclusions/Significance The study shows that presence of soil microorganisms can alleviate the negative effect of a common thyme monoterpene on the performance of an associated plant species, emphasizing the role of soil microbes in modulating plant-plant chemical interactions. PMID:22125596

  17. Microbial genome-enabled insights into plant-microorganism interactions.

    Science.gov (United States)

    Guttman, David S; McHardy, Alice C; Schulze-Lefert, Paul

    2014-12-01

    Advances in genome-based studies on plant-associated microorganisms have transformed our understanding of many plant pathogens and are beginning to greatly widen our knowledge of plant interactions with mutualistic and commensal microorganisms. Pathogenomics has revealed how pathogenic microorganisms adapt to particular hosts, subvert innate immune responses and change host range, as well as how new pathogen species emerge. Similarly, culture-independent community profiling methods, coupled with metagenomic and metatranscriptomic studies, have provided the first insights into the emerging field of research on plant-associated microbial communities. Together, these approaches have the potential to bridge the gap between plant microbial ecology and plant pathology, which have traditionally been two distinct research fields.

  18. Organotins and microorganisms. Yuki suzu kagobutsu to biseibutsu

    Energy Technology Data Exchange (ETDEWEB)

    Shinoda, S.; Onogi, H. (Okayama Univ., Okayama (Japan). Faculty of Pharmaceutical Sciences)

    1992-08-10

    Tributyltin (TBT) and triphenyltin have higher toxicity than other organotin compounds and are used as biocides, but in recent years the pollution of water and aquatic organisms has become a social problem. This paper describes the interaction between organotin compounds and microorganisms, centering on the decomposition of TBT. Part of microalgae whose activity is promoted by light or nutritive salts within an aquatic environment play an important role in TBT decomposition. Diatoms, and dinoflagellataes are mentioned as the examples. Moreover, an example in which microorganisms promote the transformation of inorganotin compounds to dimethyltin or trimethyltin is given. However, it is pointed out in this paper that the action of microorganisms relates greatly to the continuance of existence of organotins in environments, but the degradation efficiency is considered to be very low and prevention against pollution is of primary importance. 32 refs., 2 figs., 3 tabs.

  19. Microscale interactions between earthworms and microorganisms: a review

    Directory of Open Access Journals (Sweden)

    Zirbes, L.

    2012-01-01

    Full Text Available Microorganisms are well adapted to their soil microhabitat where they live together in consortia, interacting with other living members, including earthworms. This literature review consists of four sections that focus on microscale interactions between earthworms and microorganisms. The first part is devoted to nephridia symbiosis. Recent discoveries show that Verminephrobacter spp. is present as a symbiont in earthworm nephridia. The second section deals with earthworm food preference and focuses on the major hypotheses of foraging strategies. The third section presents evidence of gut symbionts and highlights the need for additional studies in this field. The last section of this review explains why microorganism activities are enhanced in burrows and casts of earthworms.

  20. Use of Probiotic Microorganisms for Bio-Protective Aims

    Directory of Open Access Journals (Sweden)

    Filiz YANGILAR

    2015-03-01

    Full Text Available It was known that some diseases can be treated as the result of the use of antibiotics in certain periods and at certain dosages while inactivating and deteriorating normal microorganisms performing useful activities in human metabolism (in especially intestinal flora. It was occured that after the use of antibiotics, some defects can be seen resulting from antibiotics (such as allergy, diarrhea, gas formation etc. With this aim, nutraceutics and functional food have gained importance over the last years and consumers began to be interested in probiotics, natural antioxidants, dietary fibres, products with low calorie and cholesterol contents, especially the products containing probioticbacteria. Bacteriocins produced by probiotic bacteria can play important roles as food protective and safeguarding since they can compete with unwanted or pathogen microorganisms survive in the media and colonize in intestines. In this review, is aimed to emphasis bioprotective compounds, advantages and disadvantages of biopreservation method and the importance of the mechanisms of probiotic microorganisms.

  1. Removal of triazine herbicides from freshwater systems using photosynthetic microorganisms

    International Nuclear Information System (INIS)

    Gonzalez-Barreiro, O.; Rioboo, C.; Herrero, C.; Cid, A.

    2006-01-01

    The uptake of the triazine herbicides, atrazine and terbutryn, was determined for two freshwater photosynthetic microorganisms, the green microalga Chlorella vulgaris and the cyanobacterium Synechococcus elongatus. An extremely rapid uptake of both pesticides was recorded, although uptake rate was lower for the cyanobacterium, mainly for atrazine. Other parameters related to the herbicide bioconcentration capacity of these microorganisms were also studied. Growth rate, biomass, and cell viability in cultures containing herbicide were clearly affected by herbicide uptake. Herbicide toxicity and microalgae sensitivity were used to determine the effectiveness of the bioconcentration process and the stability of herbicide removal. C. vulgaris showed higher bioconcentration capability for these two triazine herbicides than S. elongatus, especially with regard to terbutryn. This study supports the usefulness of such microorganisms, as a bioremediation technique in freshwater systems polluted with triazine herbicides

  2. Removal of triazine herbicides from freshwater systems using photosynthetic microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Barreiro, O. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain); Rioboo, C. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain); Herrero, C. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain); Cid, A. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain)]. E-mail: cid@udc.es

    2006-11-15

    The uptake of the triazine herbicides, atrazine and terbutryn, was determined for two freshwater photosynthetic microorganisms, the green microalga Chlorella vulgaris and the cyanobacterium Synechococcus elongatus. An extremely rapid uptake of both pesticides was recorded, although uptake rate was lower for the cyanobacterium, mainly for atrazine. Other parameters related to the herbicide bioconcentration capacity of these microorganisms were also studied. Growth rate, biomass, and cell viability in cultures containing herbicide were clearly affected by herbicide uptake. Herbicide toxicity and microalgae sensitivity were used to determine the effectiveness of the bioconcentration process and the stability of herbicide removal. C. vulgaris showed higher bioconcentration capability for these two triazine herbicides than S. elongatus, especially with regard to terbutryn. This study supports the usefulness of such microorganisms, as a bioremediation technique in freshwater systems polluted with triazine herbicides.

  3. Identification of beer spoilage microorganisms using the MALDI Biotyper platform.

    Science.gov (United States)

    Turvey, Michelle Elizabeth; Weiland, Florian; Meneses, Jon; Sterenberg, Nick; Hoffmann, Peter

    2016-03-01

    Beer spoilage microorganisms present a major risk for the brewing industry and can lead to cost-intensive recall of contaminated products and damage to brand reputation. The applicability of molecular profiling using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) in combination with Biotyper software was investigated for the identification of beer spoilage microorganisms from routine brewery quality control samples. Reference mass spectrum profiles for three of the most common bacterial beer spoilage microorganisms (Lactobacillus lindneri, Lactobacillus brevis and Pediococcus damnosus), four commercially available brewing yeast strains (top- and bottom-fermenting) and Dekkera/Brettanomyces bruxellensis wild yeast were established, incorporated into the Biotyper reference library and validated by successful identification after inoculation into beer. Each bacterial species could be accurately identified and distinguished from one another and from over 5600 other microorganisms present in the Biotyper database. In addition, wild yeast contaminations were rapidly detected and distinguished from top- and bottom-fermenting brewing strains. The applicability and integration of mass spectrometry profiling using the Biotyper platform into existing brewery quality assurance practices within industry were assessed by analysing routine microbiology control samples from a local brewery, where contaminating microorganisms could be reliably identified. Brewery-isolated microorganisms not present in the Biotyper database were further analysed for identification using LC-MS/MS methods. This renders the Biotyper platform a promising candidate for biological quality control testing within the brewing industry as a more rapid, high-throughput and cost-effective technology that can be tailored for the detection of brewery-specific spoilage organisms from the local environment.

  4. Influence of TiO2 Nanoparticles on Growth and Phenolic Compounds Production in Photosynthetic Microorganisms

    Directory of Open Access Journals (Sweden)

    Mattia Comotto

    2014-01-01

    Full Text Available The influence of titanium dioxide nanoparticles (pure anatase and 15% N doped anatase on the growth of Chlorella vulgaris, Haematococcus pluvialis, and Arthrospira platensis was investigated. Results showed that pure anatase can lead to a significant growth inhibition of C. vulgaris and A. platensis (17.0 and 74.1%, resp., while for H. pluvialis the nanoparticles do not cause a significant inhibition. Since in these stress conditions photosynthetic microorganisms can produce antioxidant compounds in order to prevent cell damages, we evaluated the polyphenols content either inside the cells or released in the medium. Although results did not show a significant difference in C. vulgaris, the phenolic concentrations of two other microorganisms were statistically affected by the presence of titanium dioxide. In particular, 15% N doped anatase resulted in a higher production of extracellular antioxidant compounds, reaching the concentration of 65.2 and 68.0 mg gDB-1 for H. pluvialis and A. platensis, respectively.

  5. Methyl tert-butyl ether biodegradation by indigenous aquifer microorganisms under natural and artificial oxic conditions

    Science.gov (United States)

    Landmeyer, J.E.; Chapelle, F.H.; Herlong, H.H.; Bradley, P.M.

    2001-01-01

    Microbial communities indigenous to a shallow groundwater system near Beaufort, SC, degraded milligram per liter concentrations of methyl tert-butyl ether (MTBE) under natural and artificial oxic conditions. Significant MTBE biodegradation was observed where anoxic, MTBE-contaminated groundwater discharged to a concrete-lined ditch. In the anoxic groundwater adjacent to the ditch, concentrations of MTBE were > 1 mg/L. Where groundwater discharge occurs, dissolved oxygen (DO) concentrations beneath the ditch exceeded 1.0 mg/L to a depth of 1.5 m, and MTBE concentrations decreased to CO2 in laboratory liquid culture studies, with no accumulation of intermediate compounds. Upgradient of the ditch in the anoxic, MTBE and BTEX-contaminated aquifer, addition of a soluble oxygen release compound resulted in oxic conditions and rapid MTBE biodegradation by indigenous microorganisms. In an observation well located closest to the oxygen addition area, DO concentrations increased from 0.4 to 12 mg/L in <60 days and MTBE concentrations decreased from 20 to 3 mg/L. In the same time period at a downgradient observation well, DO increased from <0.2 to 2 mg/L and MTBE concentrations decreased from 30 to <5 mg/L. These results indicate that microorganisms indigenous to the groundwater system at this site can degrade milligram per liter concentrations of MTBE under natural and artificial oxic conditions.

  6. Biotechnologies for Marine Oil Spill Cleanup: Indissoluble Ties with Microorganisms

    KAUST Repository

    Mapelli, Francesca; Scoma, Alberto; Michoud, Gregoire; Aulenta, Federico; Boon, Nico; Borin, Sara; Kalogerakis, Nicolas; Daffonchio, Daniele

    2017-01-01

    The ubiquitous exploitation of petroleum hydrocarbons (HCs) has been accompanied by accidental spills and chronic pollution in marine ecosystems, including the deep ocean. Physicochemical technologies are available for oil spill cleanup, but HCs must ultimately be mineralized by microorganisms. How environmental factors drive the assembly and activity of HC-degrading microbial communities remains unknown, limiting our capacity to integrate microorganism-based cleanup strategies with current physicochemical remediation technologies. In this review, we summarize recent findings about microbial physiology, metabolism and ecology and describe how microbes can be exploited to create improved biotechnological solutions to clean up marine surface and deep waters, sediments and beaches.

  7. Effect of enhanced UV-B radiation on motile microorganisms

    International Nuclear Information System (INIS)

    Haeder, D.P.

    1985-02-01

    The effect of slightly increased UV-B radiation was studied in four taxonomically very different microorganisms: the gliding prokaryotic cyanobacterium, Phormidium, the unicellular green alga Cosmarium, the flagellate Euglena and the cellular slime mold Dictyostelium. UV-B doses which can be expected as a result of a slight decrease of the protective ozone layer in the stratosphere, do not kill or damage the microorganisms visibly. However, such UV-B doses impair the development, motility and photoorientation of these organisms. Due to the inhibition of these physiological important parameters the organisms cannot respond adequately to the changing factors in their environment, which prevents the survival of the populations. (orig.) [de

  8. Stethoscopes as potential intrahospital carriers of pathogenic microorganisms.

    Science.gov (United States)

    Campos-Murguía, Alejandro; León-Lara, Ximena; Muñoz, Juan M; Macías, Alejandro E; Alvarez, José A

    2014-01-01

    Stethoscopes can take part in the transmission of health care-associated infections. We cultured 112 stethoscopes by direct imprint on blood agar to estimate the prevalence of potentially pathogenic microorganisms. Forty-eight (47%) produced 50 potentially pathogenic microorganisms; from these, 43 (86%) were Staphylococcus aureus, of which 18 (42%) were methicillin-resistant S. aureus. We concluded that stethoscopes should be considered as potential fomites and must be disinfected routinely before and after each patient contact. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  9. Collective Motion of Micro-organisms from Field Theoretical Viewpoint

    OpenAIRE

    Nojiri, Shin'ichi; Kawamura, Masako; Sugamoto, Akio

    1995-01-01

    We analyze the collective motion of micro-organisms in the fluid and consider the problem of the red tide. The red tide is produced by the condensation of the micro-organisms, which might be a similar phenomenon to the condensation of the strings. We propose a model of the generation of the red tide. By considering the interaction between the micro- organisms mediated by the velocity fields in the fluid, we derive the Van der Waals type equation of state, where the generation of the red tide ...

  10. Extremely thermophilic microorganisms and their polymer-hidrolytic enzymes

    Directory of Open Access Journals (Sweden)

    Andrade Carolina M.M.C.

    1999-01-01

    Full Text Available Thermophilic and hyperthermophilic microorganisms are found as normal inhabitants of continental and submarine volcanic areas, geothermally heated sea-sediments and hydrothermal vents and thus are considered extremophiles. Several present or potential applications of extremophilic enzymes are reviewed, especially polymer-hydrolysing enzymes, such as amylolytic and hemicellulolytic enzymes. The purpose of this review is to present the range of morphological and metabolic features among those microorganisms growing from 70oC to 100°C and to indicate potential opportunities for useful applications derived from these features.

  11. Biotechnologies for Marine Oil Spill Cleanup: Indissoluble Ties with Microorganisms

    KAUST Repository

    Mapelli, Francesca

    2017-05-13

    The ubiquitous exploitation of petroleum hydrocarbons (HCs) has been accompanied by accidental spills and chronic pollution in marine ecosystems, including the deep ocean. Physicochemical technologies are available for oil spill cleanup, but HCs must ultimately be mineralized by microorganisms. How environmental factors drive the assembly and activity of HC-degrading microbial communities remains unknown, limiting our capacity to integrate microorganism-based cleanup strategies with current physicochemical remediation technologies. In this review, we summarize recent findings about microbial physiology, metabolism and ecology and describe how microbes can be exploited to create improved biotechnological solutions to clean up marine surface and deep waters, sediments and beaches.

  12. 2.3. Global-scale atmospheric dispersion of microorganisms

    Science.gov (United States)

    Griffin, Dale W.; Gonzalez-Martin, Cristina; Hoose, C.; Smith, D.J.; Delort, Anne-Marie; Amato, Pierre

    2018-01-01

    This chapter addresses long-range dispersion and the survival of microorganisms across a wide range of altitudes in Earth's atmosphere. Topics include mechanisms of dispersion, survivability of microorganisms known to be associated with long-range transport, natural and artificial sources of bioaerosols, residence time estimation through the use of proxy aerosols, transport and emission models, and monitoring assays (both culture and molecular based). We conclude with a discussion of the known limits for Earth's biosphere boundary, relating aerobiology studies to planetary exploration given the large degree of overlapping requirements for in situ studies (including low biomass life detection and contamination control).

  13. Toxics Release Inventory (TRI)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Toxics Release Inventory (TRI) is a dataset compiled by the U.S. Environmental Protection Agency (EPA). It contains information on the release and waste...

  14. Engineering Encounters: Reverse Engineering

    Science.gov (United States)

    McGowan, Veronica Cassone; Ventura, Marcia; Bell, Philip

    2017-01-01

    This column presents ideas and techniques to enhance your science teaching. This month's issue shares information on how students' everyday experiences can support science learning through engineering design. In this article, the authors outline a reverse-engineering model of instruction and describe one example of how it looked in our fifth-grade…

  15. Detection of arboviruses and other micro-organisms in experimentally infected mosquitoes using massively parallel sequencing.

    Directory of Open Access Journals (Sweden)

    Sonja Hall-Mendelin

    Full Text Available Human disease incidence attributed to arbovirus infection is increasing throughout the world, with effective control interventions limited by issues of sustainability, insecticide resistance and the lack of effective vaccines. Several promising control strategies are currently under development, such as the release of mosquitoes trans-infected with virus-blocking Wolbachia bacteria. Implementation of any control program is dependent on effective virus surveillance and a thorough understanding of virus-vector interactions. Massively parallel sequencing has enormous potential for providing comprehensive genomic information that can be used to assess many aspects of arbovirus ecology, as well as to evaluate novel control strategies. To demonstrate proof-of-principle, we analyzed Aedes aegypti or Aedes albopictus experimentally infected with dengue, yellow fever or chikungunya viruses. Random amplification was used to prepare sufficient template for sequencing on the Personal Genome Machine. Viral sequences were present in all infected mosquitoes. In addition, in most cases, we were also able to identify the mosquito species and mosquito micro-organisms, including the bacterial endosymbiont Wolbachia. Importantly, naturally occurring Wolbachia strains could be differentiated from strains that had been trans-infected into the mosquito. The method allowed us to assemble near full-length viral genomes and detect other micro-organisms without prior sequence knowledge, in a single reaction. This is a step toward the application of massively parallel sequencing as an arbovirus surveillance tool. It has the potential to provide insight into virus transmission dynamics, and has applicability to the post-release monitoring of Wolbachia in mosquito populations.

  16. Stimuli-Responsive Materials for Controlled Release Applications

    KAUST Repository

    Li, Song

    2015-01-01

    The controlled release of therapeutics has been one of the major challenges for scientists and engineers during the past three decades. To address this outstanding problem, the design and fabrication of stimuli-responsive materials are pursued

  17. Direct cell writing of 3D microorgan for in vitro pharmacokinetic model.

    Science.gov (United States)

    Chang, Robert; Nam, Jae; Sun, Wei

    2008-06-01

    A novel targeted application of tissue engineering is the development of an in vitro pharmacokinetic model for drug screening and toxicology. An in vitro pharmacokinetic model is needed to realistically and reliably predict in vivo human response to drug administrations and potential toxic exposures. This paper details the fabrication process development and adaptation of microfluidic devices for the creation of such a physiologically relevant pharmacokinetic model. First, an automated syringe-based, layered direct cell writing (DCW) bioprinting process creates a 3D microorgan that biomimics the cell's natural microenvironment with enhanced functionality. Next, soft lithographic micropatterning techniques are used to fabricate a microscale in vitro device to house the 3D microorgan. This paper demonstrates the feasibility of the DCW process for freeform biofabrication of 3D cell-encapsulated hydrogel-based tissue constructs with defined reproducible patterns, direct integration of 3D constructs onto a microfluidic device for continuous perfusion drug flow, and characterization of 3D tissue constructs with predictable cell viability/proliferation outcomes and enhanced functionality over traditional culture methods.

  18. Characterisation of microorganisms responsible for EBPR in a ...

    African Journals Online (AJOL)

    The results indicated that micro-organisms were selected by the repeated anaerobic-aerobic process and some non-phosphorus accumulating organisms were eliminated. The cultured strains obtained from acclimated sludges were purified and their DNA was amplified using F27 and R1522 to 1.5 kb; the gene sequences ...

  19. Characterization of the dominant microorganisms responsible for the ...

    African Journals Online (AJOL)

    Nsiho (white kenkey) is a type of kenkey, a sour stiff dumpling, produced from fermented maize meal in Ghana. The dominant microorganisms responsible for the fermentation of nsiho were characterized by analysing samples from four traditional production sites at Anum in the Eastern Region of Ghana. During 48 h of ...

  20. Method and apparatus for detecting micro-organisms

    International Nuclear Information System (INIS)

    Mirsky, J.

    1976-01-01

    A method and apparatus is described for determining the presence and quantity of microorganisms, such as bacteria, fungi and yeast, in a given sample. The apparatus includes two sealed containers, a portion of which may be penetrated by a sharp instrument, as for example, glass vials with flexible septum tops. One container includes a radioactive nutrient medium which is capable of supporting the life process of the microorganism whose presence is being tested. The second container includes a liquid scintillation solution which absorbs the product of metabolism of the organisms. The sample is introduced into the first sealed container, for example, by means of a standard syringe. Any microorganisms present will consume the radioactive nutrient and as a result produce radioactive waste. Means are then applied to penetrate the containers and allow the flow of the radioactive metabolic product from the first container to the second container while preventing any contamination from the ambient. The liquid scintillation solution will emit light in proportion to the amount of the product of metabolism collected from the first container. This light may be detected by standard liquid scintillation counters, thus providing a qualitative and quantitative measure of the microorganism in the tested sample

  1. Methods for identifying lipoxygenase producing microorganisms on agar plates

    NARCIS (Netherlands)

    Nyyssola, A.; Heshof, R.; Haarmann, T.; Eidner, J.; Westerholm-Parvinen, A.; Langfelder, K.; Kruus, K.; Graaff, de L.H.; Buchert, J.

    2012-01-01

    Plate assays for lipoxygenase producing microorganisms on agar plates have been developed. Both potassium iodide-starch and indamine dye formation methods were effective for detecting soybean lipoxygenase activity on agar plates. A positive result was also achieved using the beta-carotene bleaching

  2. Antibiotic cytotoxic effects of microorganisms isolated from Jachymov uranium mines

    Energy Technology Data Exchange (ETDEWEB)

    Fuska, J.; Fuskova, A. (Slovenska Vysoka Skola Technicka, Bratislava (Czechoslovakia). Chemickotechnologicka Fakulta); Jilek, R. (Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia))

    1982-01-01

    Microorganisms were isolated from old relinquished uranium mines in Jachymov; they had been growing for several decades in darkness in temperatures of 5 to 12 degC and relative humidity from 80 to 100%. The concentration of uranium salts in mine waters varied from 10/sup -4/ to 10/sup -5/ g.l/sup -1/, that of Rn in the atmosphere was from 0.04 to 40 Bq.l/sup -1/. Of 324 cultures, 18.8% inhibited the growth of Bacillus subtilis, Escherichia coli and Candida pseudotropicalis and 16.6% that of HeLa cells. The frequency of microorganisms inhibiting the growth of HeLa or Ehrlich ascites cells was markedly higher in this set of cultures than among microorganisms kept in culture collections or isolated from other natural habitats. About 10% of the isolated cultures were mycelia sterilia. The following antibiotics were isolated from microorganisms obtained from uranium mines: frequentin, vermiculin, vermicillin, vermistatin, cytostipin and duclauxin.

  3. Biological characterisation of Haliclona (?gellius) sp.: sponge and associated microorganisms.

    NARCIS (Netherlands)

    Sipkema, D.; Holmes, B.; Nichols, S.A.; Blanch, H.W.

    2009-01-01

    We have characterised the northern Pacific undescribed sponge Haliclona (?gellius) sp. based on rDNA of the sponge and its associated microorganisms. The sponge is closely related to Amphimedon queenslandica from the Great Barrier Reef as the near-complete 18S rDNA sequences of both sponges were

  4. Susceptibility of some oral microorganisms to chlorhexidine and paramonochlorophenol

    OpenAIRE

    Amorim,Crystiane Venditi Gomes do; Aun,Carlos Eduardo; Mayer,Marcia Pinto Alves

    2004-01-01

    Since the use of antimicrobial agents is required in endodontic therapies, this study aimed at determining the minimum inhibitory concentrations (MICs) of chlorhexidine digluconate and paramonochlorophenol (PMC) against microorganisms commonly found in endodontic infections. Both agents were tested by agar dilution tests against Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Candida albicans, Prevotella intermedia, Porphyromonas gingivalis, Porphyromon...

  5. Identification of anaerobic microorganisms for converting kitchen waste to biogas

    International Nuclear Information System (INIS)

    Amirhossein Malakahmad; Shahrom Mohd Zain; Noor Ezlin Ahmad Basri; Shamsul Rahman Mohamed Kutty; Mohd Hasnain Isa

    2010-01-01

    Anaerobic digestion process is one of the alternative methods to convert organic waste into methane gas which is a fuel and energy source. Activities of various kinds of microorganisms are the main factor for anaerobic digestion which produces methane gas. Therefore, in this study a modified Anaerobic Baffled Reactor (ABR) with working volume of 50 liters was designed to identify the microorganisms through biogas production. The mixture of 75% kitchen waste and 25% sewage sludge was used as substrate. Observations on microorganisms in the ABR showed that there exists a small amount of protozoa (5%) and fungi (2%) in the system, but almost 93% of the microorganism population consists of bacteria. It is definitely clear that bacteria are responsible for anaerobic biodegradation of kitchen waste. Results show that in the acidification zone of the ABR (front compartments of reactor) fast growing bacteria capable of growth at high substrate levels and reduced pH was dominant. A shift to slower growing scavenging bacteria that grow better at higher pH was occurring towards the end of the reactor. Due to the ability of activity in acetate environment the percentages of Methanococcus, Methanosarcina and Methanotrix were higher than other kinds of methane former in the system. (Author)

  6. Effects of temperature on biological activity of permafrost microorganisms.

    Science.gov (United States)

    Kalyonova, L F; Novikova, M A; Subbotin, A M; Bazhin, A S

    2015-04-01

    The number and viability of microorganism specimens Bacillus spp. isolated from permafrost soil remained unchanged after incubation at temperatures of -16-37°C. Experiments on F1 CBA/Black-6 mice showed that incubation of bacteria at -5°C for 72 h promotes a decrease in their toxicity and an increase in their immunostimulating effect.

  7. Production of gaba (γ - aminobutyric acid by microorganisms: a review

    Directory of Open Access Journals (Sweden)

    Radhika Dhakal

    2012-12-01

    Full Text Available GABA (γ-aminobutyric acid is a four carbon non-protein amino acid that is widely distributed in plants, animals and microorganisms. As a metabolic product of plants and microorganisms produced by the decarboxylation of glutamic acid, GABA functions as an inhibitory neurotransmitter in the brain that directly affects the personality and the stress management. A wide range of traditional foods produced by microbial fermentation contain GABA, in which GABA is safe and eco-friendly, and also has the possibility of providing new health-benefited products enriched with GABA. Synthesis of GABA is catalyzed by glutamate decarboxylase, therefore, the optimal fermentation condition is mainly based on the biochemical properties of the enzyme. Major GABA producing microorganisms are lactic acid bacteria (LAB, which make food spoilage pathogens unable to grow and act as probiotics in the gastrointestinal tract. The major factors affecting the production of GABA by microbial fermentation are temperature, pH, fermentation time and different media additives, therefore, these factors are summarized to provide the most up-dated information for effective GABA synthesis. There has been a huge accumulation of knowledge on GABA application for human health accompanying with a demand on natural GABA supply. Only the GABA production by microorganisms can fulfill the demand with GABA-enriched health beneficial foods.

  8. Production of gaba (γ - Aminobutyric acid) by microorganisms: a review.

    Science.gov (United States)

    Dhakal, Radhika; Bajpai, Vivek K; Baek, Kwang-Hyun

    2012-10-01

    GABA (γ-aminobutyric acid) is a four carbon non-protein amino acid that is widely distributed in plants, animals and microorganisms. As a metabolic product of plants and microorganisms produced by the decarboxylation of glutamic acid, GABA functions as an inhibitory neurotransmitter in the brain that directly affects the personality and the stress management. A wide range of traditional foods produced by microbial fermentation contain GABA, in which GABA is safe and eco-friendly, and also has the possibility of providing new health-benefited products enriched with GABA. Synthesis of GABA is catalyzed by glutamate decarboxylase, therefore, the optimal fermentation condition is mainly based on the biochemical properties of the enzyme. Major GABA producing microorganisms are lactic acid bacteria (LAB), which make food spoilage pathogens unable to grow and act as probiotics in the gastrointestinal tract. The major factors affecting the production of GABA by microbial fermentation are temperature, pH, fermentation time and different media additives, therefore, these factors are summarized to provide the most up-dated information for effective GABA synthesis. There has been a huge accumulation of knowledge on GABA application for human health accompanying with a demand on natural GABA supply. Only the GABA production by microorganisms can fulfill the demand with GABA-enriched health beneficial foods.

  9. Prevalence of pathogenic microorganisms in the oral cavity and their ...

    African Journals Online (AJOL)

    This study was conducted to determine the incidence of pathogenic microorganisms associated with dental caries and antimicrobial susceptibility test of some common dentifrice sold in Kano metropolis. A total of 50 samples were used in this study. The samples were taken using swab from human oral mucosa. The swabs ...

  10. Microorganisms from hands of traditional Chinese medical doctors ...

    African Journals Online (AJOL)

    Background: In a central hospital, the heavy clinical workload makes one to overlook its hazard to health and can to a large extent promote the transmission of pathogenic microorganisms. It is not uncommon however, to observe practices that deviate from normal standards of hygiene. Hand contact between doctors of TCM ...

  11. [Ants as carriers of microorganisms in hospital environments].

    Science.gov (United States)

    Pereira, Rogério Dos Santos; Ueno, Mariko

    2008-01-01

    Concern exists regarding the real possibility of public health threats caused by pathogenic agents that are carried by urban ants. The present study had the objective of isolating and identifying the microorganisms that are associated with ants in hospital environments. One hundred and twenty-five ants of the same species were collected from different units of a university hospital. Each ant was collected using a swab soaked with physiological solution and was transferred to a tube containing brain heart infusion broth and incubated at 35 degrees C for 24 hours. From each tube, with growth, inoculations were made into specific culturing media, to isolate any microorganisms. The ants presented a high capacity for carrying microorganism groups: spore-producing Gram-positive bacilli 63.5%, Gram-negative bacilli 6.3%, Gram-positive cocci 23.1%, filamentous fungi 6.7% and yeast 0.5%. Thus, it can be inferred that ants may be one of the agents responsible for disseminating microorganisms in hospital environments.

  12. Screening of microorganisms for microbial enhanced oil recovery processes

    Energy Technology Data Exchange (ETDEWEB)

    Yonebayashi, H. [Japan National Oil Corp., Tokyo (Japan); Yoshida, S. [Japan Food Research Laboratiories, Tokyo (Japan). Div. of Microbiology; Ono, K. [Japan National Oil Corp., Chiba (Japan). Tech. Research Center; Enomoto, H. [Tohoku University, Sendai (Japan). Dept. of Geoscience and Tech.

    2000-01-01

    The objective of this study is to screen effective microorganisms for the Microbial Enhanced Oil Recovery process (or simply as MEOR). Samples of drilling cuttings, formation water, and soil were collected from domestic drilling sites and oil fields. Moreover, samples of activated-sludge and compost were collected from domestic sewage treatment facility and food treatment facility. At first, microorganisms in samples were investigated by incubation with different media; then they were isolated. By two stage-screening based on metabolizing ability, 4 strains (Bacillus licheniformis TRC-18-2-a, Enterobacter cloacae TRC-322, Bacillus subtilis TRC-4118, and Bacillus subtilis TRC-4126) were isolated as effective microorganisms for oil recovery. B. licheniformis TRC-18-2-a is a multifunctional microorganism possessing excellent surfactant productivity, and in addition it has gas, acid and polymer productivities. E. cloacae TRC-332 has gas and acid producing abilities. B. subtilis TRC-4118 and TRC-4126 are effective biosurfactant producers, and they reduce the interfacial tension to 0.04 and 0.12 dyne/cm, respectively. (author)

  13. Is arsenic biotransformation a detoxification mechanism for microorganisms?

    International Nuclear Information System (INIS)

    Rahman, M. Azizur; Hassler, Christel

    2014-01-01

    Arsenic (As) is extremely toxic to living organisms at high concentration. In aquatic systems, As exists in different chemical forms. The two major inorganic As (iAs) species are As V , which is thermodynamically stable in oxic waters, and As III , which is predominant in anoxic conditions. Photosynthetic microorganisms (e.g., phytoplankton and cyanobacteria) take up As V , biotransform it to As III , then biomethylate it to methylarsenic (MetAs) forms. Although As III is more toxic than As V , As III is much more easily excreted from the cells than As V . Therefore, majority of researchers consider the reduction of As V to As III as a detoxification process. The biomethylation process results in the conversion of toxic iAs to the less toxic pentavalent MetAs forms (monomethylarsonate; MMA V , dimethylarsonate; DMA V , and trimethylarsenic oxide; TMAO V ) and trimethylarsine (TMAO III ). However, biomethylation by microorganisms also produces monomethylarsenite (MMA III ) and dimethylarsenite (DMA III ), which are more toxic than iAs, as a result of biomethylation by the microorganisms, demonstrates the need to reconsider to what extent As biomethylation contributes to a detoxification process. In this review, we focused on the discussion of whether the biotransformation of As species in microorganisms is really a detoxification process with recent data

  14. Effect of effective microorganisms on broiler chicken performance ...

    African Journals Online (AJOL)

    A study was conducted between January and March 2001 to assess the effects of Effective Microorganisms (EM) as feed additive in broiler chicken production on growth performance. The experiment involved 210 day-old broiler chicks which were randomly allocated to 14 pens of 15 birds each. There were seven ...

  15. Plant Growth-Promoting Microorganisms for Environmental Sustainability.

    Science.gov (United States)

    Abhilash, P C; Dubey, Rama Kant; Tripathi, Vishal; Gupta, Vijai K; Singh, Harikesh B

    2016-11-01

    Agrochemicals used to meet the needs of a rapidly growing human population can deteriorate the quality of ecosystems and are not affordable to farmers in low-resource environments. Here, we propose the use of plant growth-promoting microorganisms (PGPMs) as a tool for sustainable food production without compromising ecosystems services. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Some estimates of the continuous cultivation of microorganisms

    Directory of Open Access Journals (Sweden)

    G. V. Alekseev

    2017-01-01

    Full Text Available The proteins, fats and carbohydrates received by the person traditionally from animal and vegetable sources don't cover all increasing needs of mankind any more today. At the same time proteins and fats of microorganisms with success can replace proteins and fats of a traditional origin. As protein producers microorganisms at the high content of protein in biomass and high growth rate of microorganisms have certain advantages. The present article is devoted to questions of numerical modeling of processes of cultivation of microorganisms. On the basis of the known model offered Mono in which saturation of growth rate of culture at increase in initial concentration of a substratum of S0 is considered the system of the differential equations describing the happening processes in that number before achievement of stationarity is written down. At the same time dependence of separate sizes, the systems entering the equations is insufficiently studied at change of parameters of process. The behavior of all system at violation of regulations is of interest or at unauthorized change of one of parameters. For studying of these questions numerical modeling is carried out and the basic picture of change of chemostate curves in these conditions is received

  17. General Purpose Segmentation for Microorganisms in Microscopy Images

    DEFF Research Database (Denmark)

    Jensen, Sebastian H. Nesgaard; Moeslund, Thomas B.; Rankl, Christian

    2014-01-01

    In this paper, we propose an approach for achieving generalized segmentation of microorganisms in mi- croscopy images. It employs a pixel-wise classification strategy based on local features. Multilayer percep- trons are utilized for classification of the local features and is trained for each sp...

  18. Is arsenic biotransformation a detoxification mechanism for microorganisms?

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, M. Azizur, E-mail: Mohammad.Rahman@uts.edu.au [Centre for Environmental Sustainability, School of the Environment, Faculty of Science, University of Technology, P.O. Box 123, Broadway, Sydney, NSW 2007 (Australia); Hassler, Christel [Marine and Lake Biogeochemistry, Institute F. A. Forel, University of Geneva, 10 rte de Suisse, Versoix, 1290 Switzerland (Switzerland)

    2014-01-15

    Arsenic (As) is extremely toxic to living organisms at high concentration. In aquatic systems, As exists in different chemical forms. The two major inorganic As (iAs) species are As{sup V}, which is thermodynamically stable in oxic waters, and As{sup III}, which is predominant in anoxic conditions. Photosynthetic microorganisms (e.g., phytoplankton and cyanobacteria) take up As{sup V}, biotransform it to As{sup III}, then biomethylate it to methylarsenic (MetAs) forms. Although As{sup III} is more toxic than As{sup V}, As{sup III} is much more easily excreted from the cells than As{sup V}. Therefore, majority of researchers consider the reduction of As{sup V} to As{sup III} as a detoxification process. The biomethylation process results in the conversion of toxic iAs to the less toxic pentavalent MetAs forms (monomethylarsonate; MMA{sup V}, dimethylarsonate; DMA{sup V}, and trimethylarsenic oxide; TMAO{sup V}) and trimethylarsine (TMAO{sup III}). However, biomethylation by microorganisms also produces monomethylarsenite (MMA{sup III}) and dimethylarsenite (DMA{sup III}), which are more toxic than iAs, as a result of biomethylation by the microorganisms, demonstrates the need to reconsider to what extent As biomethylation contributes to a detoxification process. In this review, we focused on the discussion of whether the biotransformation of As species in microorganisms is really a detoxification process with recent data.

  19. Isolation and identification of the microorganisms most prevalent in ...

    African Journals Online (AJOL)

    Infections of the external eye account for a significant percentage of ocular inflammations, some of which lead to visual losses as result of corneal involvement. This study purely isolated and identified the microorganisms most prevalent in external eye infections in Owerri urban (as seen Mercy Eye clinic). With the aid of ...

  20. Fossil Microorganisms in Archaean deposits of Northern Karelia

    Science.gov (United States)

    Astafieva, M. M.; Hoover, R. B.; Rozanov, A. Y.; Vrevskiy, A. B.

    2005-01-01

    Newly found biomorphic microstructures from the Upper Archaean (lopian) rocks from Northern Karelia are described. The presence of various microorganisms of bacterial nature and even cyanobacteria (and possibly eukaryotic forms) is suggested. The necessity of employing methods of electron microscopy, as well as traditional methods, while studying the very early manifestations of life in Archaean and Early Proterozoic is noted.

  1. Fossil Microorganisms and Formation of Early Precambrian Weathering Profiles

    Science.gov (United States)

    Rozanov, A. Yu; Astafieva, M. M.; Vrevsky, A. B.; Alfimova, N. A.; Matrenichev, V. A.; Hoover, R. B.

    2009-01-01

    Weathering crusts are the only reliable evidences of the existence of continental conditions. Often they are the only source of information about exogenous processes and subsequently about conditions under which the development of the biosphere occurred. A complex of diverse fossil microorganisms was discovered as a result of Scanning Electron Microscope investigations. The chemical composition of the discovered fossils is identical to that of the host rocks and is represented by Si, Al, Fe, Ca and Mg. Probably, the microorganisms fixed in rocks played the role of catalyst. The decomposition of minerals comprising the rocks and their transformation into clayey (argillaceous) minerals, most likely occurred under the influence of microorganisms. And may be unique weathering crusts of Early Precambrian were formed due to interaction between specific composition of microorganism assemblage and conditions of hypergene transformations. So it is possible to speak about colonization of land by microbes already at that time and about existence of single raw from weathering crusts (Primitive soils) to real soils.

  2. Rate of biodegradation of crude oil by microorganisms isolated from ...

    African Journals Online (AJOL)

    The rate of biodegradation of crude oil by micro-organisms isolated from crude oil sludge environment in Eket, Akwa Ibom State of Nigeria was studied. Mineral salt medium supplemented with crude oil was used and three most abundant species isolated from a crude oil sludged soil - Micrococcus varians, Bacillus subtilis ...

  3. [Long-term storage of obligate anaerobic microorganisms in glycerol].

    Science.gov (United States)

    Briukhanov, A I; Netrusov, A I

    2006-01-01

    We evaluated the possibility of storing the cultures of obligate anaerobic microorganisms (clostridia. acetogenic and sulfate-reducing bacteria, and methanogenic archaea) in 25% glycerol at -70 degrees C for a long time (up to 3 years). This method of storage is adequate to preserve cell viability in most obligate anaerobes.

  4. Mitigating cyanobacterial blooms: how effective are 'effective microorganisms'?

    NARCIS (Netherlands)

    Lürling, M.F.L.L.W.; Tolman, Y.; Euwe, M.

    2009-01-01

    This study examined the effects of 'Effective Microorganisms (EM)' on the growth of cyanobacteria, and their ability to terminate cyanobacterial blooms. The EM was tested in the form of 'mudballs' or 'Bokashi-balls', and as a suspension (EM-A) in laboratory experiments. No growth inhibition was

  5. Production of effective microorganism using halal- based sources: A ...

    African Journals Online (AJOL)

    GREGORY

    2011-12-16

    Dec 16, 2011 ... Key words: Component, effective microorganisms (EM), agriculture, halal-based source. INTRODUCTION. In recent years, with focus on feeding a rapidly growing human population, Malaysia has jeopardized the environ- ment and its natural resources, which are already under great stress. Consequently ...

  6. Color-Removal by Microorganisms Isolated from Human Hands

    Directory of Open Access Journals (Sweden)

    Tsukasa Ito

    2013-08-01

    Full Text Available Microorganisms are essential for human life. Microorganisms decompose the carbon compounds in dead animals and plants and convert them into carbon dioxide. Intestinal bacteria assist in food digestion. Some vitamins are produced by bacteria that live in the intestines. Sewage and industrial wastewater are treated by activated sludge composed of microbial communities. All of these are due to the ability of microbes to produce many enzymes that can degrade chemicals. How do teachers make students understand that microorganisms are always associated with humans, and that microorganisms have the ability to degrade chemicals? The presence of microorganisms on humans can be shown by incubating agar plates after they are touched by the hands of students. The ability of microorganisms to degrade chemicals can be shown by an analytical measurement of the degradation of chemicals. When the chemicals are dyes (colorants in water, microbial activity on degradation of dyes can be demonstrated by observing a decreasing degree of color as a result of the enzymatic activity (e.g., azoreductase. Dyes are widely used in the textile, food, and cosmetic industries. They are generally resistant to conventional biological wastewater treatment systems such as the activated sludge process (4. The discharge of wastewater containing dye pollutes surface water. The ability of microorganisms to decolorize and degrade dyes has been widely investigated to use for bioremediation purposes (5. The goal of this tip is to understand the presence of bacteria on human skin and the ability of bacteria to degrade colorant chemicals (decolorization. In this tip, students first cultivate and isolate bacteria on their hands, and then examine potential decolorization activity of each bacterium by observing the degree of color of the liquid in tubes in which bacteria isolated from students’ hands were inoculated. Decolorization activity of bacterial isolates from human skin has been

  7. Modelling the Ozone-Based Treatments for Inactivation of Microorganisms

    Directory of Open Access Journals (Sweden)

    Agnieszka Joanna Brodowska

    2017-10-01

    Full Text Available The paper presents the development of a model for ozone treatment in a dynamic bed of different microorganisms (Bacillus subtilis, B. cereus, B. pumilus, Escherichia coli, Pseudomonas fluorescens, Aspergillus niger, Eupenicillium cinnamopurpureum on a heterogeneous matrix (juniper berries, cardamom seeds initially treated with numerous ozone doses during various contact times was studied. Taking into account various microorganism susceptibility to ozone, it was of great importance to develop a sufficiently effective ozone dose to preserve food products using different strains based on the microbial model. For this purpose, we have chosen the Weibull model to describe the survival curves of different microorganisms. Based on the results of microorganism survival modelling after ozone treatment and considering the least susceptible strains to ozone, we selected the critical ones. Among tested strains, those from genus Bacillus were recognized as the most critical strains. In particular, B. subtilis and B. pumilus possessed the highest resistance to ozone treatment because the time needed to achieve the lowest level of its survival was the longest (up to 17.04 min and 16.89 min for B. pumilus reduction on juniper berry and cardamom seed matrix, respectively. Ozone treatment allow inactivate microorganisms to achieving lower survival rates by ozone dose (20.0 g O3/m3 O2, with a flow rate of 0.4 L/min and contact time (up to 20 min. The results demonstrated that a linear correlation between parameters p and k in Weibull distribution, providing an opportunity to calculate a fitted equation of the process.

  8. Potential applications of plant probiotic microorganisms in agriculture and forestry

    Directory of Open Access Journals (Sweden)

    Luciana Porto de Souza Vandenberghe

    2017-07-01

    Full Text Available Agriculture producers, pushed by the need for high productivity, have stimulated the intensive use of pesticides and fertilizers. Unfortunately, negative effects on water, soil, and human and animal health have appeared as a consequence of this indiscriminate practice. Plant probiotic microorganisms (PPM, also known as bioprotectants, biocontrollers, biofertilizers, or biostimulants, are beneficial microorganisms that offer a promising alternative and reduce health and environmental problems. These microorganisms are involved in either a symbiotic or free-living association with plants and act in different ways, sometimes with specific functions, to achieve satisfactory plant development. This review deals with PPM presentation and their description and function in different applications. PPM includes the plant growth promoters (PGP group, which contain bacteria and fungi that stimulate plant growth through different mechanisms. Soil microflora mediate many biogeochemical processes. The use of plant probiotics as an alternative soil fertilization source has been the focus of several studies; their use in agriculture improves nutrient supply and conserves field management and causes no adverse effects. The species related to organic matter and pollutant biodegradation in soil and abiotic stress tolerance are then presented. As an important way to understand not only the ecological role of PPM and their interaction with plants but also the biotechnological application of these cultures to crop management, two main approaches are elucidated: the culture-dependent approach where the microorganisms contained in the plant material are isolated by culturing and are identified by a combination of phenotypic and molecular methods; and the culture-independent approach where microorganisms are detected without cultivating them, based on extraction and analyses of DNA. These methods combine to give a thorough knowledge of the microbiology of the studied

  9. Halophilic microorganisms in deteriorated historic buildings: insights into their characteristics.

    Science.gov (United States)

    Adamiak, Justyna; Otlewska, Anna; Gutarowska, Beata; Pietrzak, Anna

    2016-01-01

    Historic buildings are constantly being exposed to numerous climatic changes such as damp and rainwater. Water migration into and out of the material's pores can lead to salt precipitation and the so-called efflorescence. The structure of the material may be seriously threatened by salt crystallization. A huge pressure is produced when salt hydrates occupy larger spaces, which leads at the end to cracking, detachment and material loss. Halophilic microorganisms have the ability to adapt to high salinity because of the mechanisms of inorganic salt (KCl or NaCl) accumulation in their cells at concentrations isotonic to the environment, or compatible solutes uptake or synthesis. In this study, we focused our attention on the determination of optimal growth conditions of halophilic microorganisms isolated from historical buildings in terms of salinity, pH and temperature ranges, as well as biochemical properties and antagonistic abilities. Halophilic microorganisms studied in this paper could be categorized as a halotolerant group, as they grow in the absence of NaCl, as well as tolerate higher salt concentrations (Staphylococcus succinus, Virgibacillus halodenitrificans). Halophilic microorganisms have been also observed (Halobacillus styriensis, H. hunanensis, H. naozhouensis, H. litoralis, Marinococcus halophilus and yeast Sterigmatomyces halophilus). With respect to their physiological characteristics, cultivation at a temperature of 25-30°C, pH 6-7, NaCl concentration for halotolerant and halophilic microorganisms, 0-10% and 15-30%, respectively, provides the most convenient conditions. Halophiles described in this study displayed lipolytic, glycolytic and proteolytic activities. Staphylococcus succinus and Marinococcus halophilus showed strong antagonistic potential towards bacteria from the Bacillus genus, while Halobacillus litoralis displayed an inhibiting ability against other halophiles.

  10. Modelling the Ozone-Based Treatments for Inactivation of Microorganisms

    Science.gov (United States)

    Brodowska, Agnieszka Joanna; Nowak, Agnieszka; Kondratiuk-Janyska, Alina; Piątkowski, Marcin; Śmigielski, Krzysztof

    2017-01-01

    The paper presents the development of a model for ozone treatment in a dynamic bed of different microorganisms (Bacillus subtilis, B. cereus, B. pumilus, Escherichia coli, Pseudomonas fluorescens, Aspergillus niger, Eupenicillium cinnamopurpureum) on a heterogeneous matrix (juniper berries, cardamom seeds) initially treated with numerous ozone doses during various contact times was studied. Taking into account various microorganism susceptibility to ozone, it was of great importance to develop a sufficiently effective ozone dose to preserve food products using different strains based on the microbial model. For this purpose, we have chosen the Weibull model to describe the survival curves of different microorganisms. Based on the results of microorganism survival modelling after ozone treatment and considering the least susceptible strains to ozone, we selected the critical ones. Among tested strains, those from genus Bacillus were recognized as the most critical strains. In particular, B. subtilis and B. pumilus possessed the highest resistance to ozone treatment because the time needed to achieve the lowest level of its survival was the longest (up to 17.04 min and 16.89 min for B. pumilus reduction on juniper berry and cardamom seed matrix, respectively). Ozone treatment allow inactivate microorganisms to achieving lower survival rates by ozone dose (20.0 g O3/m3 O2, with a flow rate of 0.4 L/min) and contact time (up to 20 min). The results demonstrated that a linear correlation between parameters p and k in Weibull distribution, providing an opportunity to calculate a fitted equation of the process. PMID:28991199

  11. Evidence and identification of microorganisms in argillite from Tournemire (France)

    International Nuclear Information System (INIS)

    Urios, L.; Magot, M.; Marsal, F.; Pellegrini, D.

    2010-01-01

    Document available in extended abstract form only. Generalised corrosion is one of the main processes taken into account in the dimensioning of non-alloy steel overpacks for high level nuclear waste packages. However, the presence of microorganisms such as sulfate-reducing bacteria in the host rock in contact with these non-alloy materials may also influence localised corrosion processes, leading to a premature loss of the overpack watertightness. Available void and presence of free water are key conditions for bacterial development, which are not often met in an argillaceous environment. Nevertheless, microbial activity has been proven to occur in argillaceous formations such as the Opalinus Clay in the Mont Terri Underground Research Laboratory. Indigenous sulfate-reducing bacteria have also been put into evidence in MX-80 bentonite, a clayey material likely to be used as engineered barrier in many countries for nuclear waste repositories. The French Institute of Radioprotection and Nuclear Safety (IRSN) has been conducting a research program at the Tournemire experimental platform on the biodiversity of Toarcian argillite, aiming at assessing the potential development of a microbial activity in deep clayey environments, disturbed or not by an excavation. The occurrence of microbial processes in this formation was first shown by the study of time evolution of the chemical and isotopic composition of fracture groundwaters collected in several boreholes. These investigations suggested that aqueous sulfates and their isotopic composition were controlled by bacterial sulfate reduction. The presence of living sulfate-reducing bacteria in water samples from an air-drilled borehole crossing a tectonic fracture (MB1) was later shown. Thus, a characterisation of the microbial biodiversity of the Toarcian argillite was launched. Samples have been collected in different locations of the Tournemire experimental platform: pieces of wall of the gallery, as well as cores from

  12. Evidence and identification of microorganisms in argillite from Tournemire (France)

    Energy Technology Data Exchange (ETDEWEB)

    Urios, L.; Magot, M. [Universite de Pau et des Pays de l' Adour, IPREM UMR 5254, Equipe Environnement et Microbiologie, IBEAS, F-64013 PAU (France); Marsal, F.; Pellegrini, D. [IRSN, DSU/SSIAD/BERIS, BP 17, 92262 Fontenay aux Roses Cedex (France)

    2010-07-01

    Document available in extended abstract form only. Generalised corrosion is one of the main processes taken into account in the dimensioning of non-alloy steel overpacks for high level nuclear waste packages. However, the presence of microorganisms such as sulfate-reducing bacteria in the host rock in contact with these non-alloy materials may also influence localised corrosion processes, leading to a premature loss of the overpack watertightness. Available void and presence of free water are key conditions for bacterial development, which are not often met in an argillaceous environment. Nevertheless, microbial activity has been proven to occur in argillaceous formations such as the Opalinus Clay in the Mont Terri Underground Research Laboratory. Indigenous sulfate-reducing bacteria have also been put into evidence in MX-80 bentonite, a clayey material likely to be used as engineered barrier in many countries for nuclear waste repositories. The French Institute of Radioprotection and Nuclear Safety (IRSN) has been conducting a research program at the Tournemire experimental platform on the biodiversity of Toarcian argillite, aiming at assessing the potential development of a microbial activity in deep clayey environments, disturbed or not by an excavation. The occurrence of microbial processes in this formation was first shown by the study of time evolution of the chemical and isotopic composition of fracture groundwaters collected in several boreholes. These investigations suggested that aqueous sulfates and their isotopic composition were controlled by bacterial sulfate reduction. The presence of living sulfate-reducing bacteria in water samples from an air-drilled borehole crossing a tectonic fracture (MB1) was later shown. Thus, a characterisation of the microbial biodiversity of the Toarcian argillite was launched. Samples have been collected in different locations of the Tournemire experimental platform: pieces of wall of the gallery, as well as cores from

  13. Bioprinting of Micro-Organ Tissue Analog for Drug Metabolism Study

    Science.gov (United States)

    Sun, Wei

    An evolving application of tissue engineering is to develop in vitro 3D cell/tissue models for drug screening and pharmacological study. In order to test in space, these in vitro models are mostly manufactured through micro-fabrication techniques and incorporate living cells with MEMS or microfluidic devices. These cell-integrated microfluidic devices, or referred as microorgans, are effective in furnishing reliable and inexpensive drug metabolism and toxicity studies [1-3]. This paper will present an on-going research collaborated between Drexel University and NASA JSC Radiation Physics Laboratory for applying a direct cell printing technique to freeform fabrication of 3D liver tissue analog in drug metabolism study. The paper will discuss modeling, design, and solid freeform fabrication of micro-fluidic flow patterns and bioprinting of 3D micro-liver chamber that biomimics liver physiological microenvironment for enhanced drug metabolization. Technical details to address bioprinting of 3D liver tissue analog, integration with a microfluidic device, and basic drug metabolism study for NASA's interests will presented. 1. Holtorf H. Leslie J. Chang R, Nam J, Culbertson C, Sun W, Gonda S, "Development of a Three-Dimensional Tissue-on-a-Chip Micro-Organ Device for Pharmacokinetic Analysis", the 47th Annual Meeting of the American Society for Cell Biology, Washington, DC, December 1-5, 2007. 2. Chang, R., Nam, J., Culbertson C., Holtorf, H., Jeevarajan, A., Gonda, S. and Sun, W., "Bio-printing and Modeling of Flow Patterns for Cell Encapsulated 3D Liver Chambers For Pharmacokinetic Study", TERMIS North America 2007 Conference and Exposition, Westin Harbour Castle, Toronto, Canada, June 13-16, 2007. 3.Starly, B., Chang, R., Sun, W., Culbertson, C., Holtorf, H. and Gonda, S., "Bioprinted Tissue-on-chip Application for Pharmacokinetic Studies", Proceedings of World Congress on Tissue Engineering and Regenerative Medicine, Pittsburgh, PA, USA, April 24-27, 2006.

  14. Release rates from waste packages in a salt repository

    International Nuclear Information System (INIS)

    Chambre, P.L.; Hwang, Y.; Lee, W.W.L.; Pigford, T.H.

    1987-06-01

    In this report we present estimates of radionuclide release rates from waste packages into salt. This conservative and bounding analysis shows that release rates from waste packages in salt are well below the US Nuclear Regulatory Commission's performance objectives for the engineered barrier system. 2 refs., 2 figs

  15. Engineer Ethics

    International Nuclear Information System (INIS)

    Lee, Dae Sik; Kim, Yeong Pil; Kim, Yeong Jin

    2003-03-01

    This book tells of engineer ethics such as basic understanding of engineer ethics with history of engineering as a occupation, definition of engineering and specialized job and engineering, engineer ethics as professional ethics, general principles of ethics and its limitation, ethical theory and application, technique to solve the ethical problems, responsibility, safety and danger, information engineer ethics, biotechnological ethics like artificial insemination, life reproduction, gene therapy and environmental ethics.

  16. Metabolic engineering of Saccharomyces cerevisiae for C4-dicarboxylic acid production

    NARCIS (Netherlands)

    Zelle, R.M.

    2011-01-01

    Biotechnological production of chemicals from renewable feedstocks offers a sustainable alternative to petrochemistry. Understanding of the biology of microorganisms and plants is increasing at an unprecedented rate and tools with which these organisms can be engineered for industrial application

  17. Introducing Molecular Biology to Environmental Engineers through Development of a New Course.

    Science.gov (United States)

    Oerther, Daniel B.

    2002-01-01

    Introduces a molecular biology course designed for environmental engineering majors using 16S ribosomal ribonucleic acid-targeted technology that allows students to identify and study microorganisms in bioreactor environments. (Contains 17 references.) (YDS)

  18. Engineering microbes for efficient production of chemicals

    Science.gov (United States)

    Gong, Wei; Dole, Sudhanshu; Grabar, Tammy; Collard, Andrew Christopher; Pero, Janice G; Yocum, R Rogers

    2015-04-28

    This present invention relates to production of chemicals from microorganisms that have been genetically engineered and metabolically evolved. Improvements in chemical production have been established, and particular mutations that lead to those improvements have been identified. Specific examples are given in the identification of mutations that occurred during the metabolic evolution of a bacterial strain genetically engineered to produce succinic acid. This present invention also provides a method for evaluating the industrial applicability of mutations that were selected during the metabolic evolution for increased succinic acid production. This present invention further provides microorganisms engineered to have mutations that are selected during metabolic evolution and contribute to improved production of succinic acid, other organic acids and other chemicals of commercial interest.

  19. Raft-like membrane domains in pathogenic microorganisms.

    Science.gov (United States)

    Farnoud, Amir M; Toledo, Alvaro M; Konopka, James B; Del Poeta, Maurizio; London, Erwin

    2015-01-01

    The lipid bilayer of the plasma membrane is thought to be compartmentalized by the presence of lipid-protein microdomains. In eukaryotic cells, microdomains composed of sterols and sphingolipids, commonly known as lipid rafts, are believed to exist, and reports on the presence of sterol- or protein-mediated microdomains in bacterial cell membranes are also appearing. Despite increasing attention, little is known about microdomains in the plasma membrane of pathogenic microorganisms. This review attempts to provide an overview of the current state of knowledge of lipid rafts in pathogenic fungi and bacteria. The current literature on characterization of microdomains in pathogens is reviewed, and their potential role in growth, pathogenesis, and drug resistance is discussed. Better insight into the structure and function of membrane microdomains in pathogenic microorganisms might lead to a better understanding of their pathogenesis and development of raft-mediated approaches for therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Experimental studies of biodegradation of asphalt by microorganisms

    International Nuclear Information System (INIS)

    Mine, Tatsuya; Mihara, Morihiro; Ooi, Takao; Lin, Kong-hua; Kawakami, Yasushi

    2000-04-01

    On the geological disposal system of the radioactive wastes, the activities of the microorganisms that could degrade the asphalt might be significant for the assessment of the system performance. As the main effects of the biodegradation of the asphalt, the fluctuation of leaching behavior of the nuclides included in asphalt waste has been indicated. In this study, the asphalt biodegradation test was carried out. The microorganism of which asphalt degradation ability was comparatively higher under aerobic condition and anaerobic condition was used. The asphalt biodegradation rate was calculated and it was evaluated whether the asphalt biodegradation in this system could occur. The results show that the asphalt biodegradation rate under anaerobic and high alkali condition will be 300 times lower than under aerobic and neutral pH. (author)

  1. Synthesis of biosurfactants and their advantages to microorganisms and mankind.

    Science.gov (United States)

    Cameotra, Swaranjit Singh; Makkar, Randhir S; Kaur, Jasminder; Mehta, S K

    2010-01-01

    Biosurfactants are surface-active compounds synthesized by a wide variety of microorganisms. They are molecules that have both hydrophobic and hydrophilic 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. The low water solubility of these hydrophobic 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 applications in bioremediation. Not only are the biosurfactants useful in a variety of industrial processes, they are also of vital importance to the microbes in adhesion, emulsification, bioavailability, desorption and defense strategy. These interesting facts are discussed in this chapter.

  2. Electrode Cultivation and Interfacial Electron Transport in Subsurface Microorganisms

    Science.gov (United States)

    Karbelkar, A. A.; Jangir, Y.; Reese, B. K.; Wanger, G.; Anderson, C.; El-Naggar, M.; Amend, J.

    2016-12-01

    Continental subsurface environments can present significant energetic challenges to the resident microorganisms. While these environments are geologically diverse, potentially allowing energy harvesting by microorganisms that catalyze redox reactions, many of the abundant electron donors and acceptors are insoluble and therefore not directly bioavailable. Microbes can use extracellular electron transfer (EET) as a metabolic strategy to interact with redox active surfaces. This process can be mimicked on electrode surfaces and hence can lead to enrichment and quantification of subsurface microorganisms A primary bioelectrochemical enrichment with different oxidizing and reducing potentials set up in a single bioreactor was applied in situ to subsurface microorganisms residing in iron oxide rich deposits in the Sanford Underground Research Facility. Secondary enrichment revealed a plethora of classified and unclassified subsurface microbiota on both oxidizing and reducing potentials. From this enrichment, we have isolated a Gram-positive Bacillus along with Gram-negative Cupriavidus and Anaerospora strains (as electrode reducers) and Comamonas (as an electrode oxidizer). The Bacillus and Comamonas isolates were subjected to a detailed electrochemical characterization in half-reactors at anodic and cathodic potentials, respectively. An increase in cathodic current upon inoculation and cyclic voltammetry measurements confirm the hypothesis that Comamonas is capable of electron uptake from electrodes. In addition, measurements of Bacillus on anodes hint towards novel mechanisms that allow EET from Gram-positive bacteria. This study suggests that electrochemical approaches are well positioned to dissect such extracellular interactions that may be prevalent in the subsurface, while using physical electrodes to emulate the microhabitats, redox and geochemical gradients, and the spatially dependent interspecies interactions encountered in the subsurface. Electrochemical

  3. The complexity of wine: clarifying the role of microorganisms.

    Science.gov (United States)

    Tempère, Sophie; Marchal, Axel; Barbe, Jean-Christophe; Bely, Marina; Masneuf-Pomarede, Isabelle; Marullo, Philippe; Albertin, Warren

    2018-05-01

    The concept of wine complexity has gained considerable interest in recent years, both for wine consumers and wine scientists. As a consequence, some research programs concentrate on the factors that could improve the perceived complexity of a wine. Notably, the possible influence of microbiological factors is particularly investigated. However, wine complexity is a multicomponent concept not easily defined. In this review, we first describe the actual knowledge regarding wine complexity, its perception, and wine chemical composition. In particular, we emphasize that, contrary to expectations, the perception of wine complexity is not related to wine chemical complexity. Then, we review the impact of wine microorganisms on wine complexity, with a specific focus on publications including sensory analyses. While microorganisms definitively can impact wine complexity, the underlying mechanisms and molecules are far from being deciphered. Finally, we discuss some prospective research fields that will help improving our understanding of wine complexity, including perceptive interactions, microbial interactions, and other challenging phenomena.

  4. Impacts of Triclosan in Grey water on Soil Microorganisms

    International Nuclear Information System (INIS)

    Harrow, D.I; Felker, J.M; Baker, K.H

    2011-01-01

    The use of grey water for irrigation is becoming a common practice in arid regions such as the Southwestern US, the Middle East, Australia, and China. While grey water supplies nutrients to soil ecosystems, the possible impact of trace contaminants, particularly pharmaceuticals and personal care products, has not been determined. This paper examined the impact of triclosan, an antibacterial agent commonly added to consumer products, on microbial populations and microbial diversity in soil irrigated with grey water. While there was no change in the total number of heterotrophic microorganisms in the soil, both the types and the antibiotic resistance of the microorganisms were significantly influenced by triclosan. The proportion of the microbial isolates resistant to antibiotics increased while at the same time, overall diversity of the microbial community decreased.

  5. Role and functions of beneficial microorganisms in sustainable aquaculture.

    Science.gov (United States)

    Zhou, Qunlan; Li, Kangmin; Jun, Xie; Bo, Liu

    2009-08-01

    This paper aims to review the development of scientific concepts of microecology and ecology of microbes and the role and functions of beneficial microorganisms in aquaculture and mariculture. Beneficial microorganisms play a great role in natural and man-made aquatic ecosystems based on the co-evolution theory in living biosphere on earth. Their functions are to adjust algal population in water bodies so as to avoid unwanted algal bloom; to speed up decomposition of organic matter and to reduce CODmn, NH3-N and NO2-N in water and sediments so as to improve water quality; to suppress fish/shrimp diseases and water-borne pathogens; to enhance immune system of cultured aquatic animals and to produce bioactive compounds such as vitamins, hormones and enzymes that stimulate growth, thus to decrease the FCR of feed.

  6. Ecological aspects of microorganisms inhabiting uranium mill tailings

    Science.gov (United States)

    Miller, C.L.; Landa, E.R.; Updegraff, D.M.

    1987-01-01

    Numbers and types of microorganisms in uranium mill tailings were determined using culturing techniques. Arthrobacter were found to be the predominant microorganism inhabiting the sandy tailings, whereas Bacillus and fungi predominated in the slime tailings. Sulfate-reducing bacteria, capable of leaching radium, were isolated in low numbers from tailings samples but were isolated in significantly high numbers from topsoil in contact with the tailings. The results are placed in the context of the magnitude of uranium mill tailings in the United States, the hazards posed by the tailings, and how such hazards could be enhanced or diminished by microbial activities. Patterns in the composition of the microbial population are evaluated with respect to the ecological variables that influence microbial growth. ?? 1987 Springer-Verlag New York Inc.

  7. Food environments select microorganisms based on selfish energetic behavior

    Directory of Open Access Journals (Sweden)

    Diego eMora

    2013-11-01

    Full Text Available Nutrient richness, and specifically the abundance of mono- and disaccharides that characterize several food matrixes, such as milk and grape juice, has allowed the speciation of lactic acid bacteria and yeasts with a high fermentation capacity instead of energetically favorable respiratory metabolism. In these environmental contexts, rapid sugar consumption and lactic acid or ethanol production, accumulation and tolerance, together with the ability to propagate in the absence of oxygen, are several of the ‘winning’ traits that have apparently evolved and become specialized to perfection in these fermenting microorganisms. Here, we summarize and discuss the evolutionary context that has driven energetic metabolism in food-associated microorganisms, using the dairy species Lactococcus lactis and Streptococcus thermophilus among prokaryotes and the bakers’ yeast Saccharomyces cerevisiae among eukaryotes as model organisms.

  8. The plastic-associated microorganisms of the North Pacific Gyre.

    Science.gov (United States)

    Carson, Henry S; Nerheim, Magnus S; Carroll, Katherine A; Eriksen, Marcus

    2013-10-15

    Microorganisms likely mediate processes affecting the fate and impacts of marine plastic pollution, including degradation, chemical adsorption, and colonization or ingestion by macroorganisms. We investigated the relationship between plastic-associated microorganism communities and factors such as location, temperature, salinity, plankton abundance, plastic concentration, item size, surface roughness, and polymer type. Small plastic items from the surface of the North Pacific Gyre in 2011 were examined using scanning electron microscopy. Bacillus bacteria (mean 1664 ± 247 individuals mm(-2)) and pennate diatoms (1097 ± 154 mm(-2)) were most abundant, with coccoid bacteria, centric diatoms, dinoflagellates, coccolithophores, and radiolarians present. Bacterial abundance was patchy, but increased on foamed polystyrene. Diatom abundance increased on items with rough surfaces and at sites with high plastic concentrations. Morphotype richness increased slightly on larger fragments, and a biogeographic transition occurred between pennate diatom groups. Better characterizing this community will aid in understanding how it interacts with plastic pollution. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Microorganism and filamentous fungi drive evolution of plant synapses.

    Science.gov (United States)

    Baluška, František; Mancuso, Stefano

    2013-01-01

    In the course of plant evolution, there is an obvious trend toward an increased complexity of plant bodies, as well as an increased sophistication of plant behavior and communication. Phenotypic plasticity of plants is based on the polar auxin transport machinery that is directly linked with plant sensory systems impinging on plant behavior and adaptive responses. Similar to the emergence and evolution of eukaryotic cells, evolution of land plants was also shaped and driven by infective and symbiotic microorganisms. These microorganisms are the driving force behind the evolution of plant synapses and other neuronal aspects of higher plants; this is especially pronounced in the root apices. Plant synapses allow synaptic cell-cell communication and coordination in plants, as well as sensory-motor integration in root apices searching for water and mineral nutrition. These neuronal aspects of higher plants are closely linked with their unique ability to adapt to environmental changes.

  10. Biosynthesis of Nanoparticles by Microorganisms and Their Applications

    Directory of Open Access Journals (Sweden)

    Xiangqian Li

    2011-01-01

    Full Text Available The development of eco-friendly technologies in material synthesis is of considerable importance to expand their biological applications. Nowadays, a variety of inorganic nanoparticles with well-defined chemical composition, size, and morphology have been synthesized by using different microorganisms, and their applications in many cutting-edge technological areas have been explored. This paper highlights the recent developments of the biosynthesis of inorganic nanoparticles including metallic nanoparticles, oxide nanoparticles, sulfide nanoparticles, and other typical nanoparticles. Different formation mechanisms of these nanoparticles will be discussed as well. The conditions to control the size/shape and stability of particles are summarized. The applications of these biosynthesized nanoparticles in a wide spectrum of potential areas are presented including targeted drug delivery, cancer treatment, gene therapy and DNA analysis, antibacterial agents, biosensors, enhancing reaction rates, separation science, and magnetic resonance imaging (MRI. The current limitations and future prospects for the synthesis of inorganic nanoparticles by microorganisms are discussed.

  11. Cell surface hydrophobicity of dental plaque microorganisms in situ.

    OpenAIRE

    Rosenberg, M; Judes, H; Weiss, E

    1983-01-01

    The cell surface hydrophobicity of bacteria obtained directly from human tooth surfaces was assayed by measuring their adherence to liquid hydrocarbons. Fresh samples of supragingival dental plaque were washed and dispersed in buffer. Adherence of the plaque microorganisms to hexadecane, octane, and xylene was tested turbidimetrically and by direct microscopic observation. The results clearly show that the vast majority of bacteria comprising dental plaque exhibit pronounced cell surface hydr...

  12. Activation of inoculum microorganism from dairy cattle feces

    Science.gov (United States)

    Ayuningtyas, Widya D.; Ridwan, Roni; Joni, I. M.; Marlina, E. T.; Harlia, Ellin

    2018-02-01

    Coal produces Coal Bed Methane (CBM) which is formed both biogenically and thermogenically. Lignite is not utilized optimally because it has low heat content and productivity time limit that decreases CBM production. In order to utilize lignite waste, adding inoculum consortium microorganism from dairy cattle waste as starter for biogas process can be a solution. This study aimed to produce inoculum consortium microorganism as biogas starter from dairy cattle feces through in vitro activation process by Theoudorou modification method. The research used complete randomized design with 3 replications. The treatments were blank (R0), 100% concentrate (R1), 70% concentrate+30% grass (R2), 70% grass+30% concentrate (R3) and 100% grass (R4). All treatments were added by buffer solution and feces with ratio of 2:1 into 100 ml serum injection bottle with anaerobic conditions. The parameters observed were gas production, pH and gas kinetics (orskov's equation) for 2, 4, 6, 8, 10, 12, 24 and 48 hours. The results showed that the treatment had significant effect (P <0.05) on the observed parameters. The highest total gas production was for R2 and R3 treatments with total production of 91.17 ml and 101.17 ml, pH (6.62 and 6.57), maximum gas production (94.03 and 97.62 ml), speed of gas production (0.066 and 0.084 ml/hour). There is not a significant difference for both the treatments. The source of inoculum consortium microorganisms for biogas starter selected based on the observed parameters and potential availability of proteolytic and fibrocytic microorganisms is R2 (70% concentrate +30% grass).

  13. Assessment of cellulolytic microorganisms in soils of Nevados Park, Colombia

    OpenAIRE

    Avellaneda-Torres,Lizeth Manuela; Pulido,Claudia Patricia Guevara; Rojas,Esperanza Torres

    2014-01-01

    A systematized survey was conducted to find soil-borne microbes that degrade cellulose in soils from unique ecosystems, such as the Superpáramo, Páramo, and the High Andean Forest in the Nevados National Natural Park (NNNP), Colombia. These high mountain ecosystems represent extreme environments, such as high levels of solar radiation, low atmospheric pressure, and extreme daily changes in temperature. Cellulolytic activity of the microorganisms was evaluated using qualitative tests, such as ...

  14. Isolation of Electrogenic Microorganisms with Potential to Reduce Hexavalent Chromium

    Directory of Open Access Journals (Sweden)

    Alexander Mora Collazos

    2017-01-01

    Full Text Available Isolation of cultivable microorganisms was made from the biofilm formed on the anode of a microbial fuel cell put into operation for 30 days; isolated microorganisms were evaluated for their ability to produce energy and reduce the hexavalent chromium Cr (VI. Five microorganisms were isolated, which were characterized by analysis of 16S rRNA gene, placing them in four bacterial genera: Exiguobacterium (CrMFC1, Acinetobacter (CrMFC2, Aeromonas (CrMFC3 and CrMFC5 and Serratia (CrMFC4. All isolates showed electrogenic activity and ability to reduce hexavalent chromium; the Acinetobacter CrMFC1 strain showed the best electrochemical performance registering a maximum power density of 18.61 mW/m2; the other strains showed values of maximum power density between 4.6 mW/m2and 7.1 mW/m2. Strains Aeromonas CrMFC5 and Exiguobacterium CrMFC1 showed the best rates of chromium reduction being able to reduce 100 % of the Cr (VI in less than 24 hours, the Aeromonas CrMFC5 strain was the most efficient, reducing 100 % of Cr (VI in 10 hours; the other strains reduced 100% of the contaminant after 28 to 30 hours. The microorganisms isolated in this study are hardly known for their electrogenic capacity and for reducing Cr (VI; however, show promise for their use in combined systems involving energy production system coupled to bioremediation of chromium contaminated water.

  15. Screening and characterization of useful microorganisms to arsenic removal

    OpenAIRE

    宮武, 宗利; 林, 幸男

    2007-01-01

    Microorganisms were isolated from soil and their arsenic removal abilities were evaluated. Seven out of the 100 isolated strains showed more than 20% arsenic removal. Time courses of arsenic removal and cell growth were investigated in three of these isolated strains. Although the growth rates were different, the dependence of arsenic removal on cell growth was similar in three strains (A-84, 88, 89). Strain A-89 showed highest arsenic removal rate of 63% after first day. Strain A-88 was best...

  16. Uptake of nourseothricin by the producing microorganism, Streptomyces noursei

    International Nuclear Information System (INIS)

    Roeder, B.; Graefe, U.

    1985-01-01

    The uptake of 14 C-(U)-nourseothricin by stationary phase mycelium of Streptomyces noursei JA 3890b-NG 13/14 was demonstrated. An energy-dependent transport system appears to be involved in the transport of the antibiotic. Relatively large quantities of the antibiotic were adsorbed to the surface of mycelium. Degradation of nourseothricin by the producing microorganism was not detectable. (author)

  17. The effect of adhesion on survival and growth of microorganisms

    International Nuclear Information System (INIS)

    Bar-Or, Y.

    1990-01-01

    Adhesion of microorganisms to solid surfaces or water/air interfaces can significantly influence cellular metabolic activity, development and viability. Attachment is of advantage particularly for organisms growing under oligotrophic or otherwise extreme conditions. However, the ability to detach and migrate is of vital importance when prevailing conditions become too harsh or in situations of population explosion. Adhesion can cause alterations in the physical and chemical properties of substratum surfaces as well, by means of degradation, aggregation, emulsification etc. (author) 48 refs

  18. Does nanobiotechnology create new tools to combat microorganisms?

    DEFF Research Database (Denmark)

    Zielinska-Górska, Marlena K.; Sawosz, Ewa; Górski, Konrad

    2017-01-01

    Antimicrobial resistance is still a crucial global problem related to the overuse of antibiotics and natural microorganism capability for rapid horizontal evolution. Even new generations of drugs are not able to overcome bacterial defence mechanisms. A novel solution for this immense medical...... challenge can be nanomaterials. Researchers indicate that modern nanoforms can effectively support and perhaps in the long-term replace traditional bactericidal agents. Because of their unique physicochemical properties, nanotechnology products can exert multiple actions against bacteria, which might...

  19. Using natural biomass microorganisms for drinking water denitrification.

    Science.gov (United States)

    Costa, Darleila Damasceno; Gomes, Anderson Albino; Fernandes, Mylena; Lopes da Costa Bortoluzzi, Roseli; Magalhães, Maria de Lourdes Borba; Skoronski, Everton

    2018-07-01

    Among the methods that are studied to eliminate nitrate from drinking water, biological denitrification is an attractive strategy. Although several studies report the use of denitrifying bacteria for nitrate removal, they usually involve the use of sewage sludge as biomass to obtain the microbiota. In the present study, denitrifying bacteria was isolated from bamboo, and variable parameters were controlled focusing on optimal bacterial performance followed by physicochemical analysis of water adequacy. In this way, bamboo was used as a source of denitrifying microorganisms, using either Immobilized Microorganisms (IM) or Suspended Microorganisms (SM) for nitrate removal. Denitrification parameters optimization was carried out by analysis of denitrification at different pH values, temperature, nitrate concentrations, carbon sources as well as different C/N ratios. In addition, operational stability and denitrification kinetics were evaluated. Microorganisms present in the biomass responsible for denitrification were identified as Proteus mirabilis. The denitrified water was submitted to physicochemical treatment such as coagulation and flocculation to adjust to the parameters of color and turbidity to drinking water standards. Denitrification using IM occurred with 73% efficiency in the absence of an external carbon source. The use of SM provided superior denitrification efficiency using ethanol (96.46%), glucose (98.58%) or glycerol (98.5%) as carbon source. The evaluation of the operational stability allowed 12 cycles of biomass reuse using the IM and 9 cycles using the SM. After physical-chemical treatment, only SM denitrified water remained within drinking water standards parameters of color and turbidity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Generation of PHB from Spent Sulfite Liquor Using Halophilic Microorganisms.

    Science.gov (United States)

    Weissgram, Michaela; Gstöttner, Janina; Lorantfy, Bettina; Tenhaken, Raimund; Herwig, Christoph; Weber, Hedda K

    2015-06-08

    Halophilic microorganisms thrive at elevated concentrations of sodium chloride up to saturation and are capable of growing on a wide variety of carbon sources like various organic acids, hexose and also pentose sugars. Hence, the biotechnological application of these microorganisms can cover many aspects, such as the treatment of hypersaline waste streams of different origin. Due to the fact that the high osmotic pressure of hypersaline environments reduces the risk of contamination, the capacity for cost-effective non-sterile cultivation can make extreme halophilic microorganisms potentially valuable organisms for biotechnological applications. In this contribution, the stepwise use of screening approaches, employing design of experiment (DoE) on model media and subsequently using industrial waste as substrate have been implemented to investigate the applicability of halophiles to generate PHB from the industrial waste stream spent sulfite liquor (SSL). The production of PHB on model media as well as dilutions of industrial substrate in a complex medium has been screened for by fluorescence microscopy using Nile Blue staining. Screening was used to investigate the ability of halophilic microorganisms to withstand the inhibiting substances of the waste stream without negatively affecting PHB production. It could be shown that neither single inhibiting substances nor a mixture thereof inhibited growth in the investigated range, hence, leaving the question on the inhibiting mechanisms open. However, it could be demonstrated that some haloarchaea and halophilic bacteria are able to produce PHB when cultivated on 3.3% w/w dry matter spent sulfite liquor, whereas H. halophila was even able to thrive on 6.6% w/w dry matter spent sulfite liquor and still produce PHB.

  1. Biotransformation of citrus aromatics nootkatone and valencene by microorganisms.

    Science.gov (United States)

    Furusawa, Mai; Hashimoto, Toshihiro; Noma, Yoshiaki; Asakawa, Yoshinori

    2005-11-01

    Biotransformations of the sesquiterpene ketone nootkatone from the crude drug Alpiniae Fructus and grapefruit oil, and the sesquiterpene hydrocarbon valencene from Valencia orange oil were carried out with microorganisms such as Aspergillus niger, Botryosphaeria dothidea, and Fusarium culmorum to afford structurally interesting metabolites. Their stereostructures were established by a combination of high-resolution NMR spectral and X-ray crystallographic analysis and chemical reaction. Metabolic pathways of compounds and by A. niger are proposed.

  2. Coal Enrichment Methods by Using Microorganisms and Their Metabolites

    Directory of Open Access Journals (Sweden)

    Małgorzata Deska

    2018-03-01

    Full Text Available The aim of this study is to review the literature on the methods of low-rank coal enrichment by using microorganisms and their metabolites. Effective bio-beneficiation technologies for low-rank coals in the future are also suggested throughout this paper. An extensive literature review highlights recent advances in bio-beneficiation technologies for low rank coals. This paper presents the state of the art in the field of the bio-beneficiation technology - carbon leaching with the aid of microorganisms, especially fungi. The knowledge of the low-rank coals leaching is an important step to meet the carbon eco-requirements and improve the economics of mining companies. There are several reasons to investigate microbial activities towards coal. This paper presents the current state of knowledge concerning bioleaching of coal. Thus, in view of the increasing importance of hard coal as a raw material and energy source, it seems hopeful to study the potential of microorganisms to modify the low-rank coal structure.

  3. Detection of extracellular proteases from microorganisms on agar plates

    Directory of Open Access Journals (Sweden)

    Alane Beatriz Vermelho

    1996-12-01

    Full Text Available We present herein an improved assay for detecting the presence of extracellular proteases from microorganisms on agar plates. Using different substrates (gelatin, BSA, hemoglobin incorporated into the agar and varying the culture medium composition, we were able to detect proteolytic activities from Pseudomonas aeruginosa, Micrococcus luteus and Serratia marcescens as well as the influence that these components displayed in the expression of these enzymes. For all microorganisms tested we found that in agar-BHI or yeast extract medium containing gelatin the sensitivity of proteinase detection was considerably greater than in BSA-agar or hemoglobin-agar. However, when BSA or hemoglobin were added to the culture medium, there was an increase in growth along with a marked reduction in the amount of proteinase production. In the case of M. luteus the incorporation of glycerol in BHI or yeast extract gelatin-agar induced protease liberation. Our results indicate that the technique described here is of value for detecting extracellular proteases directly in the culture medium, by means of a qualitative assay, simple, inexpensive, straight forward method to assess the presence of the proteolytic activity of a given microorganism colony with great freedom in substrate selection.

  4. MICROORGANISMS IN SELECTED CONFECTIONARY PRODUCTS DURING THE MANUFACTURING PROCESS

    Directory of Open Access Journals (Sweden)

    Jana Petrová

    2015-02-01

    Full Text Available The aim of our study was to evaluate the microbiological quality confectionery products during production. A total of 135 samples were analyzed: 45 samples of the punch balls, 45 Venček samples and 45 samples French cubes from home, school and private production. For microorganism cultivation VRBL agar for the isolation of coliform bacteria, DRBC and DG18 for microscopic fungi and yeasts, Plate Count Agar for total viable count, Meat peptone agar for mesophilic aerobic bacteria, XLD agar for Salmonella sp. and Baird Parker agar for Staphylococcus aureus were used. Following microbiological parameters were tested: total viable count, mesophilic anaerobic microorganisms, coliform bacteria, yeast and microscopic filamentous fungi, Salmonella spp. and Staphylococcus aureus. Products are assessed according to the limit values of the number of microorganisms contained in the Codex Alimentary of the Slovak Republic. The overall assessment of the microbiological quality of the punch balls, we found that two samples from school factory and one sample from private producer did not meet CA SR for the total viable count. Comparing the microbiological quality of Venček with CA SR, we found that one sample of home production did not meet the requirements for this type of product. All the tested samples were Staphylococcus aureus and Salmonella spp. negative. Comparing the results of the samples with French cubes CA SR, we found that all the samples satisfy requirements.

  5. Periodontopathic microorganisms in peripheric blood after scaling and root planing.

    Science.gov (United States)

    Lafaurie, Gloria Inés; Mayorga-Fayad, Isabel; Torres, María Fernanda; Castillo, Diana Marcela; Aya, Maria Rosario; Barón, Alexandra; Hurtado, Paola Andrea

    2007-10-01

    The objective of this study was to evaluate the frequency of periodontopathic and other subgingival anaerobic and facultative bacteria in the bloodstream following scaling and root planing (SRP). Forty-two patients with severe generalized chronic periodontitis (GChP) and generalized aggressive periodontitis (GAgP) were included in the study. Four samples of peripheric blood were drawn from the cubital vein at different times: Pre-treatment: immediately before the SRP procedure (T1), immediately after treatment (T2), 15 min. post-treatment (T3) and 30 min. post-treatment (T4). In order to identify the presence of microorganisms in blood, subcultures were conducted under anaerobic conditions. 80.9% of the patients presented positive cultures after SRP and it occurred more frequently immediately after treatment; however, 19% of the patients still had microorganisms in the bloodstream 30 min. after the procedure. The periodontopathic microorganisms more frequently identified were Porphyromonas gingivalis and Micromonas micros. Campylobacter spp., Eikenella corrodens, Tannerella forsythensis, Fusobacterium spp. and Prevotella intermedia were isolated less often. Actinomyces spp. were also found frequently during bacteraemia after SRP. SRP induced bacteraemia associated with anaerobic bacteria, especially in patients with periodontal disease.

  6. Selection of potential microorganism for sago starch fermentation

    Directory of Open Access Journals (Sweden)

    RUTH MELLIAWATI

    2006-02-01

    Full Text Available Fermentation process of sago starch for the production of bioproduct requires potential microorganism that have ability to hydrolyze sago starch. The purpose of this research was to get the potential of amylolytic microorganisms for their capability of amyloglucosidase activity and to know the sugar strains of the fermentation result. Eleven amylolytic microorganisms (9 strains of mold and 2 strains of yeast were obtained from the collection Research Centre for Biotechnology – Indonesian Institute of Sciences (LIPI, Cibinong-Bogor were used. The selection step was carried out based on their capability of starch hydrolysis to reducing sugar. The best result indicates that the production of reducing sugar reached the highest 18.485 ppm and amyloglucosidase activities was 3.583 units by KTU-1 strain. The highest total acid obtained was 5.85 mg/mL by Rhizopus IFO.R5442. The cell biomass was obtained between 0.5 to 1.74 g dry weight/100 mL and pH of the final fermentation (72 h were 3.57 to 8.38.

  7. The diversity of microorganisms associated with Acromyrmex leafcutter ants

    Directory of Open Access Journals (Sweden)

    Boomsma Jacobus J

    2002-05-01

    Full Text Available Abstract Background Molecular biological techniques are dramatically changing our view of microbial diversity in almost any environment that has so far been investigated. This study presents a systematic survey of the microbial diversity associated with a population of Acromyrmex leafcutter ants. In contrast to previous studies on social insects, which targeted specific groups of symbionts occurring in the gut (termites, Tetraponera ants or in specialised cells (Camponotus ants the objective of our present study was to do a total screening of all possible micro-organisms that can be found inside the bodies of these leafcutter ants. Results We amplified, cloned and sequenced SSU rRNA encoding gene fragments from 9 microbial groups known to have insect-associated representatives, and show that: (1 representatives of 5 out of 9 tested groups are present, (2 mostly several strains per group are present, adding up to a total of 33 different taxa. We present the microbial taxa associated with Acromymex ants in a phylogenetic context (using sequences from GenBank to assess and illustrate to which known microorganisms they are closely related. The observed microbial diversity is discussed in the light of present knowledge on the evolutionary history of Acromyrmex leafcutter ants and their known mutualistic and parasitic symbionts. Conclusions The major merits of the screening approach documented here is its high sensitivity and specificity, which allowed us to identify several microorganisms that are promising candidates for further study of their interactions with Acromyrmex leafcutter ants or their gardens.

  8. Development of Novel Drugs from Marine Surface Associated Microorganisms

    Directory of Open Access Journals (Sweden)

    Suhelen Egan

    2010-03-01

    Full Text Available While the oceans cover more than 70% of the Earth’s surface, marine derived microbial natural products have been largely unexplored. The marine environment is a habitat for many unique microorganisms, which produce biologically active compounds (“bioactives” to adapt to particular environmental conditions. For example, marine surface associated microorganisms have proven to be a rich source for novel bioactives because of the necessity to evolve allelochemicals capable of protecting the producer from the fierce competition that exists between microorganisms on the surfaces of marine eukaryotes. Chemically driven interactions are also important for the establishment of cross-relationships between microbes and their eukaryotic hosts, in which organisms producing antimicrobial compounds (“antimicrobials”, may protect the host surface against over colonisation in return for a nutrient rich environment. As is the case for bioactive discovery in general, progress in the detection and characterization of marine microbial bioactives has been limited by a number of obstacles, such as unsuitable culture conditions, laborious purification processes, and a lack of de-replication. However many of these limitations are now being overcome due to improved microbial cultivation techniques, microbial (meta- genomic analysis and novel sensitive analytical tools for structural elucidation. Here we discuss how these technical advances, together with a better understanding of microbial and chemical ecology, will inevitably translate into an increase in the discovery and development of novel drugs from marine microbial sources in the future.

  9. Toxicity of fluoride to microorganisms in biological wastewater treatment systems.

    Science.gov (United States)

    Ochoa-Herrera, Valeria; Banihani, Qais; León, Glendy; Khatri, Chandra; Field, James A; Sierra-Alvarez, Reyes

    2009-07-01

    Fluoride is a common contaminant in a variety of industrial wastewaters. Available information on the potential toxicity of fluoride to microorganisms implicated in biological wastewater treatment is very limited. The objective of this study was to evaluate the inhibitory effect of fluoride towards the main microbial populations responsible for the removal of organic constituents and nutrients in wastewater treatment processes. The results of short-term batch bioassays indicated that the toxicity of sodium fluoride varied widely depending on the microbial population. Anaerobic microorganisms involved in various metabolic steps of anaerobic digestion processes were found to be very sensitive to the presence of fluoride. The concentrations of fluoride causing 50% metabolic inhibition (IC(50)) of propionate- and butyrate-degrading microorganisms as well as mesophilic and thermophilic acetate-utilizing methanogens ranged from 18 to 43 mg/L. Fluoride was also inhibitory to nitrification, albeit at relatively high levels (IC(50)=149 mg/L). Nitrifying bacteria appeared to adapt rapidly to fluoride, and a near complete recovery of their metabolic activity was observed after only 4d of exposure to high fluoride levels (up to 500 mg/L). All other microbial populations evaluated in this study, i.e., glucose fermenters, aerobic glucose-degrading heterotrophs, denitrifying bacteria, and H(2)-utilizing methanogens, tolerated fluoride at very high concentrations (>500 mg/L).

  10. Characterization of Microorganisms Isolated from Petroleum Hydrocarbon Polluted Soil

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    Adriana Criste

    2016-02-01

    Full Text Available Bioremediation has received a great deal of attention, and bacteria isolated from polluted soil can be usedin that process. In this study, we performed an evaluation of the physiological groups of microorganisms fromsoil contaminated with petroleum. Bacterial strains were isolated from contaminated soil using the selectiveenrichment technique. Minimal Salt Media was used for serial dilutions to determine viable cell count. Thenumber of total viable cells and different types of microorganisms in the original sample was determined by serialdilution, agar plating procedure using selective media. The plates were incubated at 300C for 24-72 hours. Distinctcolonies growing on each plate were selected, and stored at freezing temperatures. The bacterial colonies werethen identified by Gram staining and biochemical tests. Following our research, it was observed that although thetotal microbial load of soil is relatively close in value, there are differences regarding the physiological group ofmicroorganisms. In the oil contaminated soil sample the largest group of microorganisms was the nitrous nitrifyingbacteria followed by nitrate bacteria. All bacterial strains that were isolated from soil samples contaminated withhydrocarbons but also the Pseudomonas putida and Bacillus subtillis strains can use diesel fuel as a food source.With the increase of diesel fuel concentration from culture medium, the majority of the bacterial strains that wereused in our experiments showed an increased value of absorbance. This fact suggests that these strains can be usedin bioremediation processes.

  11. Antimicrobial activity of jasmine oil against oral microorganisms

    Science.gov (United States)

    Thaweboon, S.; Thaweboon, B.; Kaypetch, R.

    2018-02-01

    Jasmine sambac is a species of jasmine indigenous to the tropical and warm temperature regions in particular West and Southeast Asia. Essential oil extracted from the flowers of J. sambac has been shown to have anti-oxidant activity. However, very little information regarding antimicrobial activity especially oral microorganisms exists. Objective: To investigate antimicrobial effect of essential oil extracted from flowers of J. sambac against various oral microorganisms. Materials and Methods: Oral microbial strains used in the study were Streptococcus mutans KPSK2, Staphylococcus aureus ATCC 5638, Lactobacillus casei ATCC 6363, Klebsiella pneumoniae (clinical isolate), Escherichia coli ATCC 25922, Candida albicans ATCC 10231, Candida krusei ATCC 6258, Candida parapsilosis ATCC 22019, Candida tropicalis (clinical isolate), Candida glabrata ATCC 90030, Candida pseudotropicalis (clinical isolate) and Candida stellatoidia (clinical isolate). The potential of microbial growth inhibition of the oil was firstly screened by Kirby-Bauer disk diffusion method and then the minimum inhibitory concentration (MIC) was determined by agar dilution method. Results: Jasmine oil showed antimicrobial activities against S. mutans, L. casei, E. coli and all strains of Candida species with the zones of inhibition ranging from 9 to 26 mm and MIC values of 0.19-1.56 %v/v. Conclusion: Results from the present study are scientific evidence to demonstrate that jasmine oil could be employed as a natural antimicrobial agent against oral microorganisms.

  12. Antimicrobial activity of different disinfectants against cariogenic microorganisms

    Directory of Open Access Journals (Sweden)

    Esra UZER CELIK

    Full Text Available Abstract The aim of this study was to assess the in vitro antimicrobial effects of chlorhexidine digluconate (CHX, polyhexamethylene biguanide (PHBM, and octenidine dihydrochloride (OCT on cariogenic microorganisms by using their minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC. CHX, PHBM, and OCT were diluted in distilled water to the final test concentrations. Using the in-tube dilution method, Streptococcus mutans, Lactobacillus acidophilus, Lactobacillus rhamnosus, and Actinomyces viscosus were cultivated on blood agar and Mueller–Hinton broth (MHB at 37°C for 48 h. They were read using a spectrophotometer to detect MIC. To determine MBC, samples in the range of the turbidity threshold after 24 h were transferred onto blood agar and evaluated for growth after 24 h. Different MICs and MBCs were observed in all disinfectants against each microorganism. The lowest MIC and MBC against S. mutans (60 mg/L were obtained from PHBM. The lowest values against L. rhamnosus (15 mg/L, 30 mg/L, A. viscosus (30 mg/L, and L. acidophilus (15 mg/L, 30 mg/L were determined by OCT. PHBM and OCT have the potential to be replaced with CHX because they were effective against cariogenic microorganisms.

  13. Growth response of microorganisms to different molecular fractions of lignite

    Energy Technology Data Exchange (ETDEWEB)

    Polman, J.K.; Breckenridge, C.R.; Dugan, P.R.; Quigley, D.R.

    1990-01-01

    Our research is primarily concerned with isolating and characterizing microbes which are able to dissimilate coal and convert it to other useful chemicals. This quarter, general growth responses of microorganisms cultivated in the presence of different molecular weight fractions of lignite coal were examined. Aerobic and anaerobic environmental samples from a variety of ecological niches were used as inocula. Growth of the microorganisms in these samples on the following types of media was tested: COAL medium, containing alkali-solubilized whole coal; THFI medium, containing the alkali-solubilized, tetrahydrofuran-insoluble, macromolecular portion of whole coal; THFS medium, containing the THF-soluble, low molecular weight portion of whole coal; and CON medium, void of any coal constituent. Overall results indicated that the presence of the THF-soluble, low molecular weight coal fraction enhanced the growth yield and the variety of aerobic microorganisms compared to the other coal fractions or the control medium. Conversely, anaerobic microbes grew best on media which contained the macromolecular fraction. 12 refs., 5 tabs.

  14. Preparation of microorganism free carrier for biofertilizer product

    International Nuclear Information System (INIS)

    Latiffah Norddin; Maizatul Akmam Mhd Nasir; Phua Choo Kwai Hoe

    2007-01-01

    Biofertilizer has been identified as an alternative or complementary to chemical fertilizer to increase soil fertility and crop production in sustainable farming. Biofertilizers are products containing living cells of different types of known microorganisms that may increase crop productivity through N2 fixation, phosphate solubilization or stimulation of plant growth by synthesising phytohormones. A good biofertilizer product needs a good carrier or substrate. A good carrier is free from microbial contamination and can optimise the growth of the biofertilizer microorganisms. Compost is commonly used as carrier or substrate for biofertilizer microorganisms. In the present study, compost produced by Nuclear Malaysia using the Natural Farming was used as a carrier for the biofertilizer products. Gamma irradiation has been used to produce a ?clean? or sterile carrier. The sterilization effect of the carrier was checked by using serial dilution technique. Carriers that were irradiated at 50 kGy of gamma irradiation were found to be sterile. The shelf life of the sterile carriers was also determined. After six months the compost carriers were still free from microbial contamination. (Author)

  15. Microorganisms as potential vectors of the migration of radionuclides?

    International Nuclear Information System (INIS)

    Yves, A.

    1998-01-01

    The aims of our work are the study of the sorption of radionuclides by bacteria as the first step in the microorganism-metal interaction. The latter involves the fixation of ions on a surface layer and it results in the immobilization of the metal, thus possibly being the primary step of bioaccumulation. After a rapid presentation of the direct and indirect mechanisms of the interactions, we shall present our experiments of radionuclide biosorption by bacteria. A salient feature of biosorption is the selectivity of the adsorption of some radionuclides from a composed solution. For example, Andres et al. (1993, 1995) have shown that Mycobacterium smegmatis, from a composed solution containing uranium, thorium, lanthanum, europium and ytterbium, selectively adsorbs thorium ions. The sequence of preferential fixation is: Th 4+ > UO 2 2+ > La 3+ = Eu 3+ = Yb 3+ . This selectivity is a function of the cell wall organization and of the speciation of the metal in the solution. Yet, each species of bacteria has characteristic and specific cell wall layer composition and organization. Moreover, the culture and the environmental conditions change the surface layer properties. Another parameter in the migration of radionuclides is the transfer from the soil to the microorganisms. In column experiments, Gd, and likely the rare earths, in general, adsorbed on sand can be removed with a suspension of bacteria (Thouand and Andres 1997). These examples will be discussed and serve as a basis to illustrate the diversity of the interactions between microorganisms and radionuclides

  16. Environment purification using microorganisms. Biseibutsu ni yoru kankyo joka

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, H [Asahi Glass Co. Ltd., Tokyo (Japan); Harada, S

    1993-12-01

    Technologies to purify polluted soils vary with kinds of pollutants, spread of pollution, and shapes of water veins. A method is used often that several wells are drilled in a polluted area, and water is circulated between upstream wells and downstream wells, where activities of microorganisms living in that particular environment are utilized to biodegrade the pollutants. This technology is called bioremediation. This paper deals with soil pollution by chemical substances, and describes development of a technology to remove pollution caused by PCB and petroleum which is thought difficult to apply the bioremediation technology among environment purifying technologies using microorganisms. The bioremediation of petroleum pollution assumes petroleum pollution on seashores. Discussions have been given on separation from sea water of petroleum decomposing microorganisms to be used in the bioremediation, and the number of petroleum decomposing bacteria in seas near Japan. As a result, it was made clear that a few kinds of bacteria will suffice for decomposition of main components in a mixture as complex as petroleum. 5 refs., 4 figs.

  17. The plastic-associated microorganisms of the North Pacific Gyre

    International Nuclear Information System (INIS)

    Carson, Henry S.; Nerheim, Magnus S.; Carroll, Katherine A.; Eriksen, Marcus

    2013-01-01

    Highlights: • Microorganisms mediate processes affecting the fate and impacts of marine plastic. • North Pacific Gyre (NPG) plastics were examined with scanning-electron microscopy. • Bacillus bacteria and pennate diatoms dominated the NPG plastic fouling community. • Bacterial abundance was patchily distributed but increased on foamed polystyrene. • Diatom abundance increased on rough surfaces and at sites with high plastic density. -- Abstract: Microorganisms likely mediate processes affecting the fate and impacts of marine plastic pollution, including degradation, chemical adsorption, and colonization or ingestion by macroorganisms. We investigated the relationship between plastic-associated microorganism communities and factors such as location, temperature, salinity, plankton abundance, plastic concentration, item size, surface roughness, and polymer type. Small plastic items from the surface of the North Pacific Gyre in 2011 were examined using scanning electron microscopy. Bacillus bacteria (mean 1664 ± 247 individuals mm −2 ) and pennate diatoms (1097 ± 154 mm −2 ) were most abundant, with coccoid bacteria, centric diatoms, dinoflagellates, coccolithophores, and radiolarians present. Bacterial abundance was patchy, but increased on foamed polystyrene. Diatom abundance increased on items with rough surfaces and at sites with high plastic concentrations. Morphotype richness increased slightly on larger fragments, and a biogeographic transition occurred between pennate diatom groups. Better characterizing this community will aid in understanding how it interacts with plastic pollution

  18. Pathway Design, Engineering, and Optimization.

    Science.gov (United States)

    Garcia-Ruiz, Eva; HamediRad, Mohammad; Zhao, Huimin

    The microbial metabolic versatility found in nature has inspired scientists to create microorganisms capable of producing value-added compounds. Many endeavors have been made to transfer and/or combine pathways, existing or even engineered enzymes with new function to tractable microorganisms to generate new metabolic routes for drug, biofuel, and specialty chemical production. However, the success of these pathways can be impeded by different complications from an inherent failure of the pathway to cell perturbations. Pursuing ways to overcome these shortcomings, a wide variety of strategies have been developed. This chapter will review the computational algorithms and experimental tools used to design efficient metabolic routes, and construct and optimize biochemical pathways to produce chemicals of high interest.

  19. Laser engineering of microbial systems

    Science.gov (United States)

    Yusupov, V. I.; Gorlenko, M. V.; Cheptsov, V. S.; Minaev, N. V.; Churbanova, E. S.; Zhigarkov, V. S.; Chutko, E. A.; Evlashin, S. A.; Chichkov, B. N.; Bagratashvili, V. N.

    2018-06-01

    A technology of laser engineering of microbial systems (LEMS) based on the method of laser-induced transfer of heterogeneous mixtures containing microorganisms (laser bioprinting) is described. This technology involves laser printing of soil microparticles by focusing near-infrared laser pulses on a specially prepared gel/soil mixture spread onto a gold-coated glass plate. The optimal range of laser energies from the point of view of the formation of stable jets and droplets with minimal negative impact on living systems of giant accelerations, laser pulse irradiation, and Au nanoparticles was found. Microsamples of soil were printed on glucose-peptone-yeast agar plates to estimate the LEMS process influence on structural and morphological microbial diversity. The obtained results were compared with traditionally treated soil samples. It was shown that LEMS technology allows significantly increasing the biodiversity of printed organisms and is effective for isolating rare or unculturable microorganisms.

  20. TMTI Task 1.6 Genetic Engineering Methods and Detection

    Energy Technology Data Exchange (ETDEWEB)

    Slezak, T; Lenhoff, R; Allen, J; Borucki, M; Vitalis, E; Gardner, S

    2009-12-04

    A large number of GE techniques can be adapted from other microorganisms to biothreat bacteria and viruses. Detection of GE in a microorganism increases in difficulty as the size of the genetic change decreases. In addition to the size of the engineered change, the consensus genomic sequence of the microorganism can impact the difficulty of detecting an engineered change in genomes that are highly variable from strain to strain. This problem will require comprehensive databases of whole genome sequences for more genetically variable biothreat bacteria and viruses. Preliminary work with microarrays for detecting synthetic elements or virulence genes and analytic bioinformatic approaches for whole genome sequence comparison to detect genetic engineering show promise for attacking this difficult problem but a large amount of future work remains.

  1. In vivo investigations of genetically modified microorganisms using germ-free rats

    DEFF Research Database (Denmark)

    Lund jacobsen, Bodil

    Risk evaluation of genetically modified microorganism (GMMO) in relation to human health effects brings into consideration the ability of the microorganism to survive and colonise the gastrointestinal tract and the potential gene transfer to the resident microbiota. Different biological containment...

  2. Large scientific releases

    International Nuclear Information System (INIS)

    Pongratz, M.B.

    1981-01-01

    The motivation for active experiments in space is considered, taking into account the use of active techniques to obtain a better understanding of the natural space environment, the utilization of the advantages of space as a laboratory to study fundamental plasma physics, and the employment of active techniques to determine the magnitude, degree, and consequences of artificial modification of the space environment. It is pointed out that mass-injection experiments in space plasmas began about twenty years ago with the Project Firefly releases. Attention is given to mass-release techniques and diagnostics, operational aspects of mass release active experiments, the active observation of mass release experiments, active perturbation mass release experiments, simulating an artificial modification of the space environment, and active experiments to study fundamental plasma physics

  3. The hidden face of academic researches on classified highly pathogenic microorganisms.

    Science.gov (United States)

    Devaux, Christian A

    2015-01-01

    Highly pathogenic microorganisms and toxins are manipulated in academic laboratories for fundamental research purposes, diagnostics, drugs and vaccines development. Obviously, these infectious pathogens represent a potential risk for human and/or animal health and their accidental or intentional release (biosafety and biosecurity, respectively) is a major concern of governments. In the past decade, several incidents have occurred in laboratories and reported by media causing fear and raising a sense of suspicion against biologists. Some scientists have been ordered by US government to leave their laboratory for long periods of time following the occurrence of an incident involving infectious pathogens; in other cases laboratories have been shut down and universities have been forced to pay fines and incur a long-term ban on funding after gross negligence of biosafety/biosecurity procedures. Measures of criminal sanctions have also been taken to minimize the risk that such incidents can reoccur. As United States and many other countries, France has recently strengthened its legal measures for laboratories' protection. During the past two decades, France has adopted a series of specific restriction measures to better protect scientific discoveries with a potential economic/social impact and prevent their misuse by ill-intentioned people without affecting the progress of science through fundamental research. French legal regulations concerning scientific discoveries have progressively strengthened since 2001, until the publication in November 2011 of a decree concerning the "PPST" (for "Protection du Potentiel Scientifique et Technique de la nation", the protection of sensitive scientific data). Following the same logic of protection of sensitive scientific researches, regulations were also adopted in an order published in April 2012 concerning the biology and health field. The aim was to define the legal framework that precise the conditions for authorizing

  4. Cargo Release from Polymeric Vesicles under Shear

    Directory of Open Access Journals (Sweden)

    Yingying Guo

    2018-03-01

    Full Text Available In this paper we study the release of cargo from polymeric nano-carriers under shear. Vesicles formed by two star block polymers— A 12 B 6 C 2 ( A B C and A 12 B 6 A 2 ( A B A —and one linear block copolymer— A 14 B 6 ( A B , are investigated using dissipative particle dynamics (DPD simulations. A - and C -blocks are solvophobic and B -block is solvophilic. The three polymers form vesicles of different structures. The vesicles are subjected to shear both in bulk and between solvophobic walls. In bulk shear, the mechanisms of cargo release are similar for all vesicles, with cargo travelling through vesicle membrane with no preferential release location. When sheared between walls, high cargo release rate is only observed with A B C vesicle after it touches the wall. For A B C vesicle, the critical condition for high cargo release rate is the formation of wall-polymersome interface after which the effect of shear rate in promoting cargo release is secondary. High release rate is achieved by the formation of solvophilic pathway allowing cargo to travel from the vesicle cavity to the vesicle exterior. The results in this paper show that well controlled target cargo release using polymersomes can be achieved with polymers of suitable design and can potentially be very useful for engineering applications. As an example, polymersomes can be used as carriers for surface active friction reducing additives which are only released at rubbing surfaces where the additives are needed most.

  5. High value added lipids produced by microorganisms: a potential use of sugarcane vinasse.

    Science.gov (United States)

    Fernandes, Bruna Soares; Vieira, João Paulo Fernandes; Contesini, Fabiano Jares; Mantelatto, Paulo Eduardo; Zaiat, Marcelo; Pradella, José Geraldo da Cruz

    2017-12-01

    This review aims to present an innovative concept of high value added lipids produced by heterotrophic microorganisms, bacteria and fungi, using carbon sources, such as sugars, acids and alcohols that could come from sugarcane vinasse, which is the main byproduct from ethanol production that is released in the distillation step. Vinasse is a rich carbon source and low-cost feedstock produced in large amounts from ethanol production. In 2019, the Brazilian Ministry of Agriculture, Livestock and Food Supply estimates that growth of ethanol domestic consumption will be 58.8 billion liters, more than double the amount in 2008. This represents the annual production of more than 588 billion liters of vinasse, which is currently used as a fertilizer in the sugarcane crop, due to its high concentration of minerals, mainly potassium. However, studies indicate some disadvantages such as the generation of Greenhouse Gas emission during vinasse distribution in the crop, as well as the possibility of contaminating the groundwater and soil. Therefore, the development of programs for sustainable use of vinasse is a priority. One profitable alternative is the fermentation of vinasse, followed by an anaerobic digester, in order to obtain biomaterials such as lipids, other byproducts, and methane. Promising high value added lipids, for instance carotenoids and polyunsaturated fatty acids (PUFAS), with a predicted market of millions of US$, could be produced using vinasse as carbon source, to guide an innovative concept for sustainable production. Example of lipids obtained from the fermentation of compounds present in vinasse are vitamin D, which comes from yeast sucrose fermentation and Omega 3, which can be obtained by bacteria and fungi fermentation. Additionally, several other compounds present in vinasse can be used for this purpose, including sucrose, ethanol, lactate, pyruvate, acetate and other carbon sources. Finally, this paper illustrates the potential market and

  6. A possible role of ground-based microorganisms on cloud formation in the atmosphere

    Science.gov (United States)

    Ekström, S.; Nozière, B.; Hultberg, M.; Alsberg, T.; Magnér, J.; Nilsson, E. D.; Artaxo, P.

    2010-01-01

    The formation of clouds is an important process for the atmosphere, the hydrological cycle, and climate, but some aspects of it are not completely understood. In this work, we show that microorganisms might affect cloud formation without leaving the Earth's surface by releasing biological surfactants (or biosurfactants) in the environment, that make their way into atmospheric aerosols and could significantly enhance their activation into cloud droplets. In the first part of this work, the cloud-nucleating efficiency of standard biosurfactants was characterized and found to be better than that of any aerosol material studied so far, including inorganic salts. These results identify molecular structures that give organic compounds exceptional cloud-nucleating properties. In the second part, atmospheric aerosols were sampled at different locations: a temperate coastal site, a marine site, a temperate forest, and a tropical forest. Their surface tension was measured and found to be below 30 mN/m, the lowest reported for aerosols, to our knowledge. This very low surface tension was attributed to the presence of biosurfactants, the only natural substances able to reach to such low values. The presence of strong microbial surfactants in aerosols would be consistent with the organic fractions of exceptional cloud-nucleating efficiency recently found in aerosols, and with the correlations between algae bloom and cloud cover reported in the Southern Ocean. The results of this work also suggest that biosurfactants might be common in aerosols and thus of global relevance. If this is confirmed, a new role for microorganisms on the atmosphere and climate could be identified.

  7. Screening of thermotolerant microorganisms and application for oil separation from palm oil mill wastewater

    Directory of Open Access Journals (Sweden)

    Aran H-Kittikun

    2007-05-01

    Full Text Available The characteristics of palm oil mill wastewater (POMW were brown color, pH 3.8-4.3, temperature 48-55oC, total solids 68.2-82.1 g/l, suspended solids 26.2-65.6 g/l, oil and grease 19.1-25.1 g/l, COD 49.9-160.7g/l and BOD 32.5-75.3 g/l. After centrifugation (3,184 xg of 50 ml POMW for 10 min, the POMW was separated into 3 layers: top (oil, middle (supernatant and bottom layer (sediment. The sediment containeddry weight 1.19 g and oil and grease 1.07 g. In order to release oil and grease trapped in palm fiber debris in the POMW, cellulase- and/or xylanase-enzyme-producing and thermotolerant microorganisms wereisolated. The isolates SO1 and SO2 were isolated from soil near the first anaerobic pond of the palm oil mill. They were aerobic, Gram positive, rod shaped, thermotolerant microorganisms and produced cellulase 12.11 U/ml (3 days and 7.2 U/ml (4 days, and xylanase 50.98 U/ml (4 days and 20.42 U/ml (4 days, respectivelyin synthetic medium containing carboxymethycellulose as a carbon source. When these 2 isolates were added into the steriled POMW under shaking condition for 7 days, after centrifugation at 3,184 xg the isolate SO1gave the better % reduction of dry weight (64.66 % and of oil and grease in the bottom layer (85.32 % of the POMW.

  8. Caesium accumulation by microorganisms: uptake mechanisms, cation competition, compartmentalization and toxicity

    International Nuclear Information System (INIS)

    Avery, S.V.

    1995-01-01

    The continued release of caesium radioisotopes into the environment has led to a resurgence of interest in microbe-Cs interactions. Caesium exists almost exclusively as the monovalent cation Cs + in the natural environment. Although Cs + is a weak Lewis acid that exhibits a low tendency to form complexes with ligands, its chemical similarity to the biologically essential alkali cation K + facilitates high levels of metabolism-dependent intracellular accumulation. Microbial Cs + (K + ) uptake is generally mediated by monovalent cation transport systems located on the plasma membrane. These differ widely in specificity for alkali cations and consequently microorganisms display large differences in their ability to accumulate Cs + ; Cs + appears to have an equal or greater affinity than K + for transport in certain microorganisms. Microbial Cs + accumulation is markedly influenced by the presence of external cations, e.g. K + , Na + , NH 4 + and H + , and is generally accompanied by an approximate stoichiometric exchange for intracellular K + . However, stimulation of growth of K + -starved microbial cultures by Cs + is limited and it has been proposed that it is not the presence of Cs + in cells that is growth inhibitory but rather the resulting loss of K + . Increased microbial tolerance to Cs + may result from sequestration of Cs + in vacuoles or changes in the activity and/or specificity of transport systems mediating Cs + uptake. The precise intracellular target(s) for Cs + - induced toxicity has yet to be clearly defined, although certain internal structures, e.g. ribosomes, become unstable in the presence of Cs + and Cs + is known to substitute poorly for K + in the activation of many K + -requiring enzymes. (author)

  9. 40 CFR 725.67 - Applications to exempt new microorganisms from this part.

    Science.gov (United States)

    2010-07-01

    ...) The effects of the new microorganism on health and the environment. (ii) The magnitude of exposure of human beings and the environment to the new microorganism. (iii) The benefits of the new microorganism... economic consequences of granting or denying the exemption, including effects on the national economy...

  10. DMPD: Signaling pathways activated by microorganisms. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17303405 Signaling pathways activated by microorganisms. Takeuchi O, Akira S. Curr ...Opin Cell Biol. 2007 Apr;19(2):185-91. Epub 2007 Feb 15. (.png) (.svg) (.html) (.csml) Show Signaling pathways activated by microorg...anisms. PubmedID 17303405 Title Signaling pathways activated by microorganisms. Auth

  11. Genetically engineered micro-organisms: Aromatic hydrocarbon biodegradation genes from Rhodococcus

    International Nuclear Information System (INIS)

    Kendall, K.

    1993-01-01

    DNA known to encode toluene biodegradation genes in Pseudomonas putida was used in Southern Blots to identify homologous DNA in the unrelated toluene degrading Actinomycete, Rhodococcus sp. ATCC 19070. Two strongly hybridizing EcoRI fragments of 2.3 kb and 2.7 kb respectively were cloned into E. coli. Sequence analysis of a 400 bp section of the 2.3 kb fragment demonstrated that it encodes proteins with similar amino acid sequences to the xylX and xylY genes of P. putida. These proteins are components of toluate oxygenase, the enzyme catalyzing the first step in the metabolism of benzoic acid

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

    OpenAIRE

    Jennifer L. Wood; Caixian Tang; Ashley E. Franks; Wuxing Liu

    2016-01-01

    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 bioremediat...

  13. Engineering opportunities in nuclear engineering

    International Nuclear Information System (INIS)

    Walton, D.G.

    1980-01-01

    The pattern of education and training of Nuclear Engineers in the UK is outlined under the headings; degree courses for professional engineers, postgraduate courses, education of technician engineers. Universities which offer specific courses are stated and useful addresses listed. (UK)

  14. Microbial engineering for the production of advanced biofuels.

    Science.gov (United States)

    Peralta-Yahya, Pamela P; Zhang, Fuzhong; del Cardayre, Stephen B; Keasling, Jay D

    2012-08-16

    Advanced biofuels produced by microorganisms have similar properties to petroleum-based fuels, and can 'drop in' to the existing transportation infrastructure. However, producing these biofuels in yields high enough to be useful requires the engineering of the microorganism's metabolism. Such engineering is not based on just one specific feedstock or host organism. Data-driven and synthetic-biology approaches can be used to optimize both the host and pathways to maximize fuel production. Despite some success, challenges still need to be met to move advanced biofuels towards commercialization, and to compete with more conventional fuels.

  15. Engineering Institute

    Science.gov (United States)

    Projects Past Projects Publications NSEC » Engineering Institute Engineering Institute Multidisciplinary engineering research that integrates advanced modeling and simulations, novel sensing systems and new home of Engineering Institute Contact Institute Director Charles Farrar (505) 665-0860 Email UCSD EI

  16. A Comprehensive Characterization of Microorganisms and Allergens in Spacecraft Environment

    Science.gov (United States)

    Castro, V.A.; Ott, C.M.; Garcia, V.M.; John, J.; Buttner, M.P.; Cruz, P.; Pierson, D.L.

    2009-01-01

    The determination of risk from infectious disease during long-duration missions is composed of several factors including the concentration and the characteristics of the infectious agent. Thus, a thorough knowledge of the microorganisms aboard spacecraft is essential in mitigating infectious disease risk to the crew. While stringent steps are taken to minimize the transfer of potential pathogens to spacecraft, several medically significant organisms have been isolated from both the Mir and International Space Station (ISS). Historically, the method for isolation and identification of microorganisms from spacecraft environmental samples depended upon their growth on culture media. Unfortunately, only a fraction of the organisms may grow on a culture medium, potentially omitting those microorganisms whose nutritional and physical requirements for growth are not met. Thus, several pathogens may not have been detected, such as Legionella pneumophila, the etiological agent of Legionnaire s disease. We hypothesize that environmental analysis using non-culture-based technologies will reveal microorganisms, allergens, and microbial toxins not previously reported in spacecraft, allowing for a more complete health assessment. The development of techniques for this flight experiment, operationally named SWAB, has already provided advances in NASA laboratory processes and beneficial information toward human health risk assessment. The translation of 16S ribosomal DNA sequencing for the identification of bacteria from the SWAB experiment to nominal operations has increased bacterial speciation of environmental isolates from previous flights three fold compared to previous conventional methodology. The incorporation of molecular-based DNA fingerprinting using repetitive sequence-based polymerase chain reaction (rep-PCR) into the capabilities of the laboratory has provided a methodology to track microorganisms between crewmembers and their environment. Both 16S ribosomal DNA

  17. The 2017 Release Cloudy

    Science.gov (United States)

    Ferland, G. J.; Chatzikos, M.; Guzmán, F.; Lykins, M. L.; van Hoof, P. A. M.; Williams, R. J. R.; Abel, N. P.; Badnell, N. R.; Keenan, F. P.; Porter, R. L.; Stancil, P. C.

    2017-10-01

    We describe the 2017 release of the spectral synthesis code Cloudy, summarizing the many improvements to the scope and accuracy of the physics which have been made since the previous release. Exporting the atomic data into external data files has enabled many new large datasets to be incorporated into the code. The use of the complete datasets is not realistic for most calculations, so we describe the limited subset of data used by default, which predicts significantly more lines than the previous release of Cloudy. This version is nevertheless faster than the previous release, as a result of code optimizations. We give examples of the accuracy limits using small models, and the performance requirements of large complete models. We summarize several advances in the H- and He-like iso-electronic sequences and use our complete collisional-radiative models to establish the densities where the coronal and local thermodynamic equilibrium approximations work.

  18. EIA new releases

    International Nuclear Information System (INIS)

    1994-09-01

    This report is a compliation of news releases from the Energy Information Administration. The september-october report includes articles on energy conservation, energy consumption in commercial buildings, and a short term energy model for a personal computer

  19. Threshold Dynamics of a Stochastic Chemostat Model with Two Nutrients and One Microorganism

    Directory of Open Access Journals (Sweden)

    Jian Zhang

    2017-01-01

    Full Text Available A new stochastic chemostat model with two substitutable nutrients and one microorganism is proposed and investigated. Firstly, for the corresponding deterministic model, the threshold for extinction and permanence of the microorganism is obtained by analyzing the stability of the equilibria. Then, for the stochastic model, the threshold of the stochastic chemostat for extinction and permanence of the microorganism is explored. Difference of the threshold of the deterministic model and the stochastic model shows that a large stochastic disturbance can affect the persistence of the microorganism and is harmful to the cultivation of the microorganism. To illustrate this phenomenon, we give some computer simulations with different intensity of stochastic noise disturbance.

  20. Sellafield (release of radioactivity)

    Energy Technology Data Exchange (ETDEWEB)

    Cunningham, J; Goodlad, A; Morris, M

    1986-02-06

    A government statement is reported, about the release of plutonium nitrate at the Sellafield site of British Nuclear Fuels plc on 5 February 1986. Matters raised included: details of accident; personnel monitoring; whether radioactive material was released from the site; need for public acceptance of BNFL activities; whether plant should be closed; need to reduce level of radioactive effluent; number of incidents at the plant.