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Sample records for cell immobilization electrophoresis

  1. Mapping and identification of interferon gamma-regulated HeLa cell proteins separated by immobilized pH gradient two-dimensional gel electrophoresis

    DEFF Research Database (Denmark)

    Shaw, A.; Larsen, M.; Roepstorff, P.

    1999-01-01

    magnitude of IFN-gamma responsive genes has been reported previously. Our goal is to identify and map IFN-gamma-regulated HeLa cell proteins to the two-dimensional polyacrylamide gel electrophoresis with the immobilized pH gradient (IPG) two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) system...

  2. Influence of Immobilized Biomolecules on Magnetic Bead Plug Formation and Retention in Capillary Electrophoresis

    Science.gov (United States)

    Henken, Rachel L.; Chantiwas, Rattikan; Gilman, S. Douglass

    2012-01-01

    Significant changes in the formation and retention of magnetic bead plugs in a capillary during electrophoresis were studied, and it was demonstrated that these effects were due to the type of biological molecule immobilized on the surface of these beads. Three biological molecules, an antibody, an oligonucleotide and alkaline phosphatase, were attached to otherwise identical streptavidin-coated magnetic beads through biotin-avidin binding in order to isolate differences in bead immobilization in a magnetic field resulting from the type of biological molecule immobilized on the bead surface. Alkaline phosphatase also was attached to the magnetic beads using epoxy groups on the bead surfaces (instead of avidin-biotin binding) to study the impact of immobilization chemistry. The formation and retention of magnetic bead plugs were studied quantitatively using light scattering detection of magnetic particles eluting from the bead plugs and qualitatively using microscopy. Both the type of biomolecule immobilized on the magnetic bead surface and the chemistry used to link the biomolecule to the magnetic bead impacted the formation and retention of the bead plugs. PMID:22437880

  3. Immobilized enzymes and cells

    Energy Technology Data Exchange (ETDEWEB)

    Bucke, C; Wiseman, A

    1981-04-04

    This article reviews the current state of the art of enzyme and cell immobilization and suggests advances which might be made during the 1980's. Current uses of immobilized enzymes include the use of glucoamylase in the production of glucose syrups from starch and glucose isomerase in the production of high fructose corn syrup. Possibilities for future uses of immobilized enzymes and cells include the utilization of whey and the production of ethanol.

  4. Surface cell immobilization within perfluoroalkoxy microchannels

    Energy Technology Data Exchange (ETDEWEB)

    Stojkovič, Gorazd; Krivec, Matic [Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana (Slovenia); Vesel, Alenka [Jožef Stefan Institute, Jamova cesta 39, 1000 Ljubljana (Slovenia); Marinšek, Marjan [Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana (Slovenia); Žnidaršič-Plazl, Polona, E-mail: polona.znidarsic@fkkt.uni-lj.si [Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana (Slovenia)

    2014-11-30

    Graphical abstract: - Highlights: • A very efficient approach for immobilization of cells into microreactors is presented. • It is applicable to various materials, including PFA and cyclic olefin (co)polymers. • It was used to immobilize different prokaryotic and eukaryotic microbes. • Cells were immobilized on the surface in high density and showed good stability. • Mechanisms of APTES interactions with target materials are proposed. - Abstract: Perfluoroalkoxy (PFA) is one of the most promising materials for the fabrication of cheap, solvent resistant and reusable microfluidic chips, which have been recently recognized as effective tools for biocatalytic process development. The application of biocatalysts significantly depends on efficient immobilization of enzymes or cells within the reactor enabling long-term biocatalyst use. Functionalization of PFA microchannels by 3-aminopropyltriethoxysilane (ATPES) and glutaraldehyde was used for rapid preparation of microbioreactors with surface-immobilized cells. X-ray photoelectron spectroscopy and scanning electron microscopy were used to accurately monitor individual treatment steps and to select conditions for cell immobilization. The optimized protocol for Saccharomyces cerevisiae immobilization on PFA microchannel walls comprised ethanol surface pretreatment, 4 h contacting with 10% APTES aqueous solution, 10 min treatment with 1% glutaraldehyde and 20 min contacting with cells in deionized water. The same protocol enabled also immobilization of Escherichia coli, Pseudomonas putida and Bacillus subtilis cells on PFA surface in high densities. Furthermore, the developed procedure has been proved to be very efficient also for surface immobilization of tested cells on other materials that are used for microreactor fabrication, including glass, polystyrene, poly (methyl methacrylate), polycarbonate, and two olefin-based polymers, namely Zeonor{sup ®} and Topas{sup ®}.

  5. In situ photo-immobilised pH gradient isoelectric focusing and zone electrophoresis integrated two-dimensional microfluidic chip electrophoresis for protein separation

    International Nuclear Information System (INIS)

    Lin, Fengmin; Yu, Shiyong; Gu, Le; Zhu, Xuetao; Wang, Jianshe; Zhu, Han; Lu, Yi; Wang, Yihua; Deng, Yulin; Geng, Lina

    2015-01-01

    A method is introduced for open-column photo-induced site-selective immobilization of pH gradients in a layer of PEG-methacrylate in a multi-dimensional microfluidic chip for use in electrophoresis. It has several attractive features: (a) mixtures of fluorescently labelled proteins carbonic anhydrase, catalase and myoglobin in their native state can be separated by pH-gradient isoelectric focusing (IEF) and zone electrophoresis (CZE) using integrated 2D chip electrophoresis; (b) compared to strip packing or monolithic photo-immobilization, it overcomes the shortcomings of free carrier ampholyte-based 2D chip electrophoresis in an easy way; (c) larger amount of sample can be loaded into the open column-mode electrophoresis (d) immobilized pH gradients can be re-used and the chip can be recycled; (e) a multilayer 3D pH gradient is established by a layer-by-layer assembly technique to further increase the separation capacity. In our perception, this strategy has a large potential in microfluidic chip-based separation schemes because of its simplicity, separation power, re-usability, and separation capacity. (author)

  6. Down-regulation of triose phosphate isomerase in Vineristine-resistant gastric cancer SGC7901 cell line identified by immobilized pH gradient two-dimensional gel electrophoresis and mierosequencing

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective:To exkplore new multidrug-resistance-related proteins in gastric SC7901 cells and clarify their mechanisms.Methods:Two-dimensional(2-D) polyacrylamide gel electrophoresis with immobilized pH gradients(IPG) was applied to compare the differential expression of multidrug-resistance-related proteins in gastric cancer SGC7901 cells and Vineristine-resistant SGC7901 cells (SGC7901/VCR) induced by vincristine sulfate.The 2-D gels were silver-stained.Then,preparative 2-D PAGE was performed.The differential proteins of PVDF membranes were cxcised and identified by N-terminal microsequencing.The mRNA expressions of differential proteins were detected in SGC 7901 cells and SGC7901/VCR cells by RT-PCR.Results:Approximatedly 680 protein sports were resolved on each 2-D gel by silver staining.Most protein spots showed no difference in composition,shape or density.25 proteins differed in abundance (6 higher in SGC7901/VCR cells;19 higher in 7901 cells);5 proteins were unique to one kind of cell or the othe(3 in SGC7901/VRC cells,2 in 7901 cells).One drug-resistance-related protein,which was down-regulated in SGC7901/VCR cells,was identified as trisephosphate isomerase(TPI),a glycolytic pathway enzyme.Conclusions:the results suggest that these differential proteins including TPI may be related to the Vincristine-resistant mechanism in human gastric cancer SGC7901/VCR cell line.

  7. Immobilization of Mortierella vinacea cells by radiation polymerization

    International Nuclear Information System (INIS)

    Kumakura, M.; Kaetsu, I.

    1983-01-01

    Immobilization of Mortierella vinacea cells, which contain active α-galactosidase, by radiation polymerization at low temperatures was studied. The durability of the enzymatic activity of the immobilized cells obtained with hydrophilic monomers was affected by the concentrations of the cells and monomer in which optimum conditions were observed. The enzymatic activity of the immobilized cells obtained with hydrophilic monomers was compared to that of hydrophobic monomers. Michaelis constants of the immobilized cells varied with monomer concentration. The effect of addition of porous solid substances on the immobilization of the cells was studied

  8. Immobilization of yeast cells by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Fujimura, T.; Kaetsu, I.

    1982-01-01

    Radiation-induced polymerization method was applied to the immobilization of yeast cells. The effects of irradiation, cooling and monomer, which are neccessary for polymerization, were recovered completely by subsequent aerobical incubation of yeast cells. The ethanol productive in immobilized yeast cells increased with the increase of aerobical incubation period. The growth of yeast cells in immobilized yeast cells was indicated. The maximum ethanol productivity in immobilized yeast cell system was around three times as much as that in free yeast cell system. (orig.)

  9. Immobilized cells of Candida rugosa possessing fumarase activity

    Energy Technology Data Exchange (ETDEWEB)

    Yang, L.; Zhone, L.

    1980-01-01

    Immobilized cells of C. rugosa that possessed fumarase activity were prepared by different methods; the most active immobilized cells were entrapped in polyacrylamide gels. The effects of pH temperature, and divalent cations on the fumarase activity of both immobilized and native cells were the same. Mn/sup 2 +/, Mg/sup 2 +/, Ca/sup 2 +/, and Fe/sup 2 +/ did not protect the immobilized enzyme against thermal inactivation. The activity of immobilized fumarase remained constant during 91 days of storage of 4-6 degrees. The immobilized cell column was used for the continuous production of L-malic acid from 1M fumarate at 30 degrees and pH 8.5. The immobilized column operated steadily for 2 months. Half life of the immobilized fumarase at 30 degrees was 95 days.

  10. Single-cell microgel electrophoresis: an in vitro assay of radiosensitivity

    International Nuclear Information System (INIS)

    Deeley, J.O.T.; Moore, J.L.

    1993-01-01

    The results obtained by a microgel electrophoresis are comparable to conventional gel electrophoresis and elution techniques (Singh et al, 1989), DNA precipitation, alkali unwinding and cell clonogenicity assays (Olive et al, 1990). Since single cells are assessed, microgel electrophoresis is particularly appropriate for end-points such as the intercell variation in response. The simplicity, low cost and rapidity of microgel electrophoresis compared with other assays makes it particularly attractive for assessing the effects on DNA of radiation and other genotoxic agents on the general population. (Author)

  11. Free-zone electrophoresis of animal cells. 1: Experiments on cell-cell interactions

    Science.gov (United States)

    Todd, P. W.; Hjerten, S.

    1985-01-01

    The electrophoretically migrating zones wasa monitored. The absence of fluid flows in the direction of migration permits direct measurement of electrophoretic velocities of any material. Sedimentation is orthogonal to electrokinetic motion and the effects of particle-particle interaction on electrophoretic mobility is studied by free zone electrophoresis. Fixed erythrocytes at high concentrations, mixtures of fixed erythrocytes from different animal species, and mixtures of cultured human cells were studied in low ionic strength buffers. The electrophoretic velocity of fixed erythrocytes was not altered by increasing cell concentration or by the mixing of erythrocytes from different species. When zones containing cultured human glial cells and neuroblastoma cells are permitted to interact during electrophoresis, altered migration patterns occur. It is found that cell-cell interactions depends upon cell type.

  12. Preparation of immobilized growing cells and enzymatic hydrolysis of sawdust

    International Nuclear Information System (INIS)

    Kumakura, M.; Kaetsu, I.

    1984-01-01

    Trichoderma reesei cells were immobilized by radiation polymerization using porous materials such as non-woven material and sawdust, and the enzymatic hydrolysis of sawdust with the enzyme solution from the immobilized growing cells was studied. The filter paper activity, which shows the magnitude of cellulase production in the immobilized cells, was comparable with that in the intact cells. The filter paper activity was affected by addition concentration of monomer and porous materials. The cells in the immobilized cells grew to be adhered on the surface of the fibrous polymers. Sawdust, which was pretreated by irradiation technique, was effectively hydrolyzed with the enzyme solution resulting from the culture of the immobilized cells, in which the glucose yield increased increasing the culture time of the immobilized cells. (author)

  13. Immobilization of Trichoderma reesei cells by radiation polymerization

    International Nuclear Information System (INIS)

    Kumakura, M.; Kaetsu, I.

    1983-01-01

    Trichoderma reesei cells were immobilized by radiation polymerization 2-hydroxyethyl acrylate monomer at low temperature. Cellulase production resulting from the growth of the cells in the porous polymer matrix of immobilized cell composites was confirmed by measuring the cellulase activity and pH during the culture. (orig.)

  14. Immobilization of microbial cells: A promising tool for treatment of ...

    African Journals Online (AJOL)

    The review articles on cell immobilization have been published since 1980 and reflect the general interest in this topic. Immobilized microbial cells create opportunities in a wide range of sectors including environmental pollution control. Compared with suspended microorganism technology, cell immobilization shows many ...

  15. Light transfer in agar immobilized microalgae cell cultures

    Science.gov (United States)

    Kandilian, Razmig; Jesus, Bruno; Legrand, Jack; Pilon, Laurent; Pruvost, Jérémy

    2017-09-01

    This paper experimentally and theoretically investigates light transfer in agar-immobilized cell cultures. Certain biotechnological applications such as production of metabolites secreted by photosynthetic microorganisms require cells to be immobilized in biopolymers to minimize contamination and to facilitate metabolite recovery. In such applications, light absorption by cells is one of the most important parameters affecting cell growth or metabolite productivity. Modeling light transfer therein can aid design and optimize immobilized-cell reactors. In this study, Parachlorella kessleri cells with areal biomass concentrations ranging from 0.36 to 16.9 g/m2 were immobilized in 2.6 mm thick agar gels. The average absorption and scattering cross-sections as well as the scattering phase function of P. kessleri cells were measured. Then, the absorption and transport scattering coefficients of the agar gel were determined using an inverse method based on the modified two-flux approximation. The forward model was used to predict the normal-hemispherical transmittance and reflectance of the immobilized-cell films accounting for absorption and scattering by both microalgae and the agar gel. Good agreement was found between the measured and predicted normal-hemispherical transmittance and reflectance provided absorption and scattering by agar were taken into account. Moreover, good agreement was found between experimentally measured and predicted mean rate of photon absorption. Finally, optimal areal biomass concentration was determined to achieve complete absorption of the incident radiation.

  16. Purification-Free, Target-Selective Immobilization of a Protein from Cell Lysates.

    Science.gov (United States)

    Cha, Jaehyun; Kwon, Inchan

    2018-02-27

    Protein immobilization has been widely used for laboratory experiments and industrial processes. Preparation of a recombinant protein for immobilization usually requires laborious and expensive purification steps. Here, a novel purification-free, target-selective immobilization technique of a protein from cell lysates is reported. Purification steps are skipped by immobilizing a target protein containing a clickable non-natural amino acid (p-azidophenylalanine) in cell lysates onto alkyne-functionalized solid supports via bioorthogonal azide-alkyne cycloaddition. In order to achieve a target protein-selective immobilization, p-azidophenylalanine was introduced into an exogenous target protein, but not into endogenous non-target proteins using host cells with amber codon-free genomic DNAs. Immobilization of superfolder fluorescent protein (sfGFP) from cell lysates is as efficient as that of the purified sfGFP. Using two fluorescent proteins (sfGFP and mCherry), the authors also demonstrated that the target proteins are immobilized with a minimal immobilization of non-target proteins (target-selective immobilization). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Immobilization of Gibberella fujikuroi cells with carriers modified by radiation polymerization

    International Nuclear Information System (INIS)

    Lu Zhaoxin; Xie Zhongchuan; Wei Qijiang

    1994-01-01

    Gibberella fujikuroi cells were immobilized on modified carriers (gauze) by using the radiation polymerization technique. The mycelium was firmly adhered to the surface of fibril covered with hydrophobic polymer, poly (diethylene glycol dimethyl acrylate) and hydrophobic-hydrophilic copolymer poly (diethylene glycol dimethyl acrylate-sodium acrylate), but it was not immobilized onto the polyethylene net, which has a similar network structure to that of the modified carrier. The weight of immobilized cells was affected by covered polymer. Gibberellic acid productivity in immobilized cells was similar to that of free cells, and the immobilized cells was of good stability. A optimum culture condition for gibberellic acid production was at pH 5.5 and under 20 ∼ 30 degree C

  18. Ethanol fermentation by immobilized cells of Zymomonas mobilis

    Energy Technology Data Exchange (ETDEWEB)

    Grote, W.

    1985-01-01

    Previous studies have shown that immobilized yeast cell cultures have commercial potential for fuel ethanol production. In this study the suitability of strains of Z. mobilis for whole cell immobilization was investigated. Experiments revealed that immobilization in Ca-alginate or K-carrageenan gel or use of flocculating strains was effective for ethanol production at relatively high productivities. Two laboratory size reactors were designed and constructed. These were a compartmented multiple discshaft column and a tower fermentor. Results of this work supported other studies that established that growth and fermentation could be uncoupled. The data indicated that specific metabolic rates were dependent on the nature of the fermentation media. The addition of lactobacilli to Z. mobilis continuous fermentations had only a transient effect, and was unlikely to affect an immobilized Z. mobilis process. With 150 gl/sup -1/ glucose media and a Z. mobilis ZM4 immobilized cell reactor, a maximum volumetric ethanol productivity of 55 gl/sup -1/h/sup -1/ was obtained. The fermentation of sucrose media or sucrose-based raw materials (molasses, cane juice, synthetic mill liquor) by immobilized Z. mobilis ZM4 revealed a pattern of rapid sucrose hydrolysis, preferential glucose utilization and the conversion of fructose to the undesirable by-products levan and sorbitol.

  19. Cell immobilization by radiation polymerization-a comparative study

    International Nuclear Information System (INIS)

    Dahlan bin Hj Mohd; Abu Bakar bin Salleh; Che Nyonya binti Abd Razak; Meheran binti Hamenudin; Kamaruzaman bin Ampon; Wan Md Zin bin Wan Yunus; Mahiran binti Basri

    1991-01-01

    An extracellular lipase producing fungus, Rhizopus rhizopodi formis was immobilised using radiation-induced polyHEMA, alginate and k-carrageenan. Immobilizations were done on spores since they showed better resistance against gamma radiation. The simultaneous radiation immobilization technique was found to be unsuitable because of contamination. Post-radiation immobilization using polyHEMA yielded 2-3 times more enzyme than the free cells. The value, however was slightly lower than the ones given by the cells immobilised using alginate or k-carrageenan, but the radiation-induced polymer was stronger and less likely to disintegrate

  20. Immobilization of microbial cell and yeast cell and its application to biomass conversion using radiation techniques

    International Nuclear Information System (INIS)

    Kaetsu, Isao; Kumakura, Minoru; Fujimura, Takashi; Kasai, Noboru; Tamada, Masao

    1987-01-01

    The recent results of immobilization of cellulase-producing cells and ethanol-fermentation yeast by radiation were reported. The enzyme of cellulase produced by immobilized cells was used for saccharification of lignocellulosic wastes and immobilized yeast cells were used for fermentation reaction from glucose to ethanol. The wastes such as chaff and bagasse were treated by γ-ray or electron-beam irradiation in the presence of alkali and subsequent mechanical crushing, to form a fine powder less than 50 μm in diameter. On the other hand, Trichoderma reesei as a cellulase-producing microbial cell was immobilized on a fibrous carrier having a specific porous structure and cultured to produce cellulase. The enzymatic saccharification of the pretreated waste was carried out using the produced cellulase. The enhanced fermentation process to produce ethanol from glucose with the immobilized yeast by radiation was also studied. The ethanol productivity of immobilized growing yeast cells thus obtained was thirteen times that of free yeast cells in a 1:1 volume of liquid medium to immobilized yeast cells. (author)

  1. Immobilization of microbial cell and yeast cell and its application to biomass conversion using radiation techniques

    Science.gov (United States)

    Kaetsu, Isao; Kumakura, Minoru; Fujimura, Takashi; Kasai, Noboru; Tamada, Masao

    The recent results of immobilization of cellulase-producing cells and ethanol-fermentation yeast by radiation were reported. The enzyme of cellulase produced by immobilized cells was used for saccharification of lignocellulosic wastes and immobilized yeast cells were used for fermentation reaction from glucose to ethanol. The wastes such as chaff and bagasse were treated by γ-ray or electron-beam irradiation in the presence of alkali and subsequent mechanical crushing, to form a fine powder less than 50 μm in diameter. On the other hand, Trichoderma reesei as a cellulase-producing microbial cell was immobilized on a fibrous carrier having a specific porous structure and cultured to produce cellulase. The enzymatic saccharification of the pretreated waste was carried out using the produced cellulase. The enhanced fermentation process to produce ethanol from glucose with the immobilized yeast by radiation was also studied. The ethanol productivity of immobilized growing yeast cells thus obtained was thirteen times that of free yeast cells in a 1:1 volume of liquid medium to immobilized yeast cells.

  2. Uranium uptake by immobilized cells of Pseudomonas strain EPS 5028

    International Nuclear Information System (INIS)

    Pons, M.P.; Fuste, M.C.

    1993-01-01

    Polyacrylamide-gel-immobilized cells of Pseudomonas strain EPS 5028 were effective in the removal of uranium (U) from synthetic effluents. Metal accumulation was performed in an open system in columns filled with immobilized cells that were challenged with continuous flows containing U. Possible variable of the system were studied. Uranium uptake by the immobilized cells of this microorganism was affected by pH but not by temperature or flow rate. In addition, U binding could be interpreted in terms of the Freundlich adsorption isotherm indicating single-layer adsorption. The feasibility of reusing the immobilized cells was suggested after the recovery of U with a solution of 0.1 M sodium carbonate. (orig.)

  3. Ethanol production by immobilized cells with forced substrate supply

    Energy Technology Data Exchange (ETDEWEB)

    Mitani, Y.; Nishizawa, Y.; Nagai, S.

    1984-01-01

    Ethanol fermentation by a forced substrate supply into an immobilized cell layer was carried out to increase the ethanol production rate and to eliminate the diffusion dependency of substrate supply in an ordinary immobilized cell reaction. Saccharomyces cerevisiae IFO 2347 was immobilized in a mixture of k-carrageenan, locust bean gum, and celite (2: 0.5: 40 wt/vol %). A glucose minimal medium was fed into the immobilized cell layer (5 to 22 mm in thickness) at retention times between 0.6 and 2.8 h under pressure. The stable ethanol fermentation could be maintained for more than 3 weeks with an ethanol yield of 0.48 g ethanol/g glucose and ethanol productivity of 63 g.(l gel)/sup -1/.h/sup -1/ at a retention time of 1.5 h. The yeast cells were well distributed through the gel layer with a vertical gradient, and an average cell density was ca. 8.0 X 10/sup 9/ cells/ml gel, 4-fold higher than that of ordinary immobilized cells. A small filter press reactor was constructed to examine the applicability of ethanol fermentation with this forced substrate supply. The operation could be continued for a month at a retention time of 2 h yielding 96 g/l of ethanol from 200 g/l of glucose. 6 references, 5 figures, 3 tables.

  4. Combinational Effect of Cell Adhesion Biomolecules and Their Immobilized Polymer Property to Enhance Cell-Selective Adhesion

    Directory of Open Access Journals (Sweden)

    Rio Kurimoto

    2016-01-01

    Full Text Available Although surface immobilization of medical devices with bioactive molecules is one of the most widely used strategies to improve biocompatibility, the physicochemical properties of the biomaterials significantly impact the activity of the immobilized molecules. Herein we investigate the combinational effects of cell-selective biomolecules and the hydrophobicity/hydrophilicity of the polymeric substrate on selective adhesion of endothelial cells (ECs, fibroblasts (FBs, and smooth muscle cells (SMCs. To control the polymeric substrate, biomolecules are immobilized on thermoresponsive poly(N-isopropylacrylamide-co-2-carboxyisopropylacrylamide (poly(NIPAAm-co-CIPAAm-grafted glass surfaces. By switching the molecular conformation of the biomolecule-immobilized polymers, the cell-selective adhesion performances are evaluated. In case of RGDS (Arg-Gly-Asp-Ser peptide-immobilized surfaces, all cell types adhere well regardless of the surface hydrophobicity. On the other hand, a tri-Arg-immobilized surface exhibits FB-selectivity when the surface is hydrophilic. Additionally, a tri-Ile-immobilized surface exhibits EC-selective cell adhesion when the surface is hydrophobic. We believe that the proposed concept, which is used to investigate the biomolecule-immobilized surface combination, is important to produce new biomaterials, which are highly demanded for medical implants and tissue engineering.

  5. Quantification of DNA damage by single-cell electrophoresis

    International Nuclear Information System (INIS)

    Ikushima, Takaji

    1990-01-01

    A simple technique of micro-agarose gel electrophoresis has been developed to quantify DNA damage in individual cells. Cells are embedded in agarose gel on microscope slides, lysed by detergents and then electrophoresed for a short time under neutral or alkaline condition. In irradiated cells, DNA migrates from the nucleus toward the anode, displaying commet-like pattern by staining with DNA-specific fluorescence dye. DNA damage is evaluated by measuring the distance of DNA migration. The technique was applied for measuring DNA damage in single cells exposed to 60 Co γ-rays, or to KUR radiation in the presence or absence of 10 B-enriched boric acid. The enhanced production of double-stranded DNA breaks by 10 B(n,α) 7 Li reaction was demonstrated here. The significant increase in the length of DNA migration was observed in single cells exposed to such a low dose as 20 cGy after alkaline micro electrophoresis. (author)

  6. Engineering cholesterol-based fibers for antibody immobilization and cell capture

    Science.gov (United States)

    Cohn, Celine

    In 2015, the United States is expected to have nearly 600,000 deaths attributed to cancer. Of these 600,000 deaths, 90% will be a direct result of cancer metastasis, the spread of cancer throughout the body. During cancer metastasis, circulating tumor cells (CTCs) are shed from primary tumors and migrate through bodily fluids, establishing secondary cancer sites. As cancer metastasis is incredibly lethal, there is a growing emphasis on developing "liquid biopsies" that can screen peripheral blood, search for and identify CTCs. One popular method for capturing CTCs is the use of a detection platform with antibodies specifically suited to recognize and capture cancer cells. These antibodies are immobilized onto the platform and can then bind and capture cells of interest. However, current means to immobilize antibodies often leave them with drastically reduced function. The antibodies are left poorly suited for cell capture, resulting in low cell capture efficiencies. This body of work investigates the use of lipid-based fibers to immobilize proteins in a way that retains protein function, ultimately leading to increased cell capture efficiencies. The resulting increased efficiencies are thought to arise from the retained three-dimensional structure of the protein as well as having a complete coating of the material surface with antibodies that are capable of interacting with their antigens. It is possible to electrospin cholesterol-based fibers that are similar in design to the natural cell membrane, providing proteins a more natural setting during immobilization. Such fibers have been produced from cholesterol-based cholesteryl succinyl silane (CSS). These fibers have previously illustrated a keen aptitude for retaining protein function and increasing cell capture. Herein the work focuses on three key concepts. First, a model is developed to understand the immobilization mechanism used by electrospun CSS fibers. The antibody immobilization and cell capturing

  7. Biodegradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1.

    Science.gov (United States)

    Tallur, Preeti N; Mulla, Sikandar I; Megadi, Veena B; Talwar, Manjunatha P; Ninnekar, Harichandra Z

    2015-01-01

    Pyrethroid pesticide cypermethrin is a environmental pollutant because of its widespread use, toxicity and persistence. Biodegradation of such chemicals by microorganisms may provide an cost-effective method for their detoxification. We have investigated the degradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1 in various matrices such as, polyurethane foam (PUF), polyacrylamide, sodium alginate and agar. The optimum temperature and pH for the degradation of cypermethrin by immobilized cells of Micrococcus sp. were found to be 30 °C and 7.0, respectively. The rate of degradation of 10 and 20 mM of cypermethrin by freely suspended cells were compared with that of immobilized cells in batches and semi-continuous with shaken cultures. PUF-immobilized cells showed higher degradation of cypermethrin (10 mM and 20 mM) than freely suspended cells and cells immobilized in other matrices. The PUF-immobilized cells of Micrococcus sp. strain CPN 1 were retain their degradation capacity. Thus, they can be reused for more than 32 cycles, without losing their degradation capacity. Hence, the PUF-immobilized cells of Micrococcus sp. could potentially be used in the bioremediation of cypermethrin contaminated water.

  8. Biodegradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1

    Directory of Open Access Journals (Sweden)

    Preeti N. Tallur

    2015-09-01

    Full Text Available Pyrethroid pesticide cypermethrin is a environmental pollutant because of its widespread use, toxicity and persistence. Biodegradation of such chemicals by microorganisms may provide an cost-effective method for their detoxification. We have investigated the degradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1 in various matrices such as, polyurethane foam (PUF, polyacrylamide, sodium alginate and agar. The optimum temperature and pH for the degradation of cypermethrin by immobilized cells of Micrococcus sp. were found to be 30 °C and 7.0, respectively. The rate of degradation of 10 and 20 mM of cypermethrin by freely suspended cells were compared with that of immobilized cells in batches and semi-continuous with shaken cultures. PUF-immobilized cells showed higher degradation of cypermethrin (10 mM and 20 mM than freely suspended cells and cells immobilized in other matrices. The PUF-immobilized cells of Micrococcus sp. strain CPN 1 were retain their degradation capacity. Thus, they can be reused for more than 32 cycles, without losing their degradation capacity. Hence, the PUF-immobilized cells of Micrococcus sp. could potentially be used in the bioremediation of cypermethrin contaminated water.

  9. Electrically conductive, immobilized bioanodes for microbial fuel cells

    International Nuclear Information System (INIS)

    Ganguli, R; Dunn, B

    2012-01-01

    The power densities of microbial fuel cells with yeast cells as the anode catalyst were significantly increased by immobilizing the yeast in electrically conductive alginate electrodes. The peak power densities measured as a function of the electrical conductivity of the immobilized electrodes show that although power increases with rising electrical conductivity, it tends to saturate beyond a certain point. Changing the pH of the anode compartment at that point seems to further increase the power density, suggesting that proton transport limitations and not electrical conductivity will limit the power density from electrically conductive immobilized anodes. (paper)

  10. The effects of cellulase on capsaicin production in freely suspended cells and immobilized cell cultures of capsicum annuum

    International Nuclear Information System (INIS)

    Islek, C.

    2014-01-01

    The effect of different concentrations of cellulase on the production of capsaicin in freely suspended cell and immobilized cell cultures of Kahramanmara pepper seeds (Capsicum annuum L.) were studied. Calluses were obtained from in vitro germinated hypocotyl explants of pepper seedlings and cell suspensions were prepared from these calluses. Immobilized cell suspension cultures with calcium alginate and free cell suspension cultures were obtained by using cell suspensions. Elicitor such as cellulase (5-30 micro g/ml), was applied both for the free and immobilized cell suspensions and control group without elicitor was prepared. The concentration of capsaicin in freely suspended cells, immobilized cells and their filtrates were identified by HPLC after extraction with ethyl acetate. It was found that the immobilization process had an increasing effect on the capsaicin accumulation. The concentration of capsaicin in the immobilized cells for both control groups and elicitor added samples was higher than the free cells. In general, capsaicin concentration in the filtrate for free cells was higher than the immobilized cells. When all the cellulase and the sampling hours were compared, the highest capsaicin concentration for the immobilized cells was determined as 362,91 micro g/ml f.w. at the 24th hour for 30 micro g/ml cellulase applied samples. (author)

  11. The Cutting Edge of Affinity Electrophoresis Technology.

    Science.gov (United States)

    Kinoshita, Eiji; Kinoshita-Kikuta, Emiko; Koike, Tohru

    2015-03-18

    Affinity electrophoresis is an important technique that is widely used to separate and analyze biomolecules in the fields of biology and medicine. Both quantitative and qualitative information can be gained through affinity electrophoresis. Affinity electrophoresis can be applied through a variety of strategies, such as mobility shift electrophoresis, charge shift electrophoresis or capillary affinity electrophoresis. These strategies are based on changes in the electrophoretic patterns of biological macromolecules that result from interactions or complex-formation processes that induce changes in the size or total charge of the molecules. Nucleic acid fragments can be characterized through their affinity to other molecules, for example transcriptional factor proteins. Hydrophobic membrane proteins can be identified by means of a shift in the mobility induced by a charged detergent. The various strategies have also been used in the estimation of association/disassociation constants. Some of these strategies have similarities to affinity chromatography, in that they use a probe or ligand immobilized on a supported matrix for electrophoresis. Such methods have recently contributed to profiling of major posttranslational modifications of proteins, such as glycosylation or phosphorylation. Here, we describe advances in analytical techniques involving affinity electrophoresis that have appeared during the last five years.

  12. Dental pulp stem cells immobilized in alginate microspheres for applications in bone tissue engineering.

    Science.gov (United States)

    Kanafi, M M; Ramesh, A; Gupta, P K; Bhonde, R R

    2014-07-01

    To immobilize dental pulp stem cells (DPSC) in alginate microspheres and to determine cell viability, proliferation, stem cell characteristics and osteogenic potential of the immobilized DPSCs. Human DPSCs isolated from the dental pulp were immobilized in 1% w/v alginate microspheres. Viability and proliferation of immobilized DPSCs were determined by trypan blue and MTT assay, respectively. Stem cell characteristics of DPSCs post immobilization were verified by labelling the cells with CD73 and CD90. Osteogenic potential of immobilized DPSCs was assessed by the presence of osteocalcin. Alizarin red staining and O-cresolphthalein complexone method confirmed and quantified calcium deposition. A final reverse transcriptase PCR evaluated the expression of osteogenic markers - ALP, Runx-2 and OCN. More than 80% of immobilized DPSCs were viable throughout the 3-week study. Proliferation appeared controlled and consistent unlike DPSCs in the control group. Presence of CD73 and CD90 markers confirmed the stem cell nature of immobilized DPSCs. The presence of osteocalcin, an osteoblastic marker, was confirmed in the microspheres on day 21. Mineralization assays showed high calcium deposition indicating elevated osteogenic potential of immobilized DPSCs. Osteogenic genes- ALP, Runx-2 and OCN were also upregulated in immobilized DPSCs. Surprisingly, immobilized DPSCs in the control group cultured in conventional stem cell media showed upregulation of osteogenic genes and expressed osteocalcin. Dental pulp stem cells immobilized in alginate hydrogels exhibit enhanced osteogenic potential while maintaining high cell viability both of which are fundamental for bone tissue regeneration. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  13. The Cutting Edge of Affinity Electrophoresis Technology

    Science.gov (United States)

    Kinoshita, Eiji; Kinoshita-Kikuta, Emiko; Koike, Tohru

    2015-01-01

    Affinity electrophoresis is an important technique that is widely used to separate and analyze biomolecules in the fields of biology and medicine. Both quantitative and qualitative information can be gained through affinity electrophoresis. Affinity electrophoresis can be applied through a variety of strategies, such as mobility shift electrophoresis, charge shift electrophoresis or capillary affinity electrophoresis. These strategies are based on changes in the electrophoretic patterns of biological macromolecules that result from interactions or complex-formation processes that induce changes in the size or total charge of the molecules. Nucleic acid fragments can be characterized through their affinity to other molecules, for example transcriptional factor proteins. Hydrophobic membrane proteins can be identified by means of a shift in the mobility induced by a charged detergent. The various strategies have also been used in the estimation of association/disassociation constants. Some of these strategies have similarities to affinity chromatography, in that they use a probe or ligand immobilized on a supported matrix for electrophoresis. Such methods have recently contributed to profiling of major posttranslational modifications of proteins, such as glycosylation or phosphorylation. Here, we describe advances in analytical techniques involving affinity electrophoresis that have appeared during the last five years. PMID:28248262

  14. Immobilization of anode-attached microbes in a microbial fuel cell.

    KAUST Repository

    Wagner, Rachel C

    2012-01-03

    Current-generating (exoelectrogenic) bacteria in bioelectrochemical systems (BESs) may not be culturable using standard in vitro agar-plating techniques, making isolation of new microbes a challenge. More in vivo like conditions are needed where bacteria can be grown and directly isolated on an electrode. While colonies can be developed from single cells on an electrode, the cells must be immobilized after being placed on the surface. Here we present a proof-of-concept immobilization approach that allows exoelectrogenic activity of cells on an electrode based on applying a layer of latex to hold bacteria on surfaces. The effectiveness of this procedure to immobilize particles was first demonstrated using fluorescent microspheres as bacterial analogs. The latex coating was then shown to not substantially affect the exoelectrogenic activity of well-developed anode biofilms in two different systems. A single layer of airbrushed coating did not reduce the voltage produced by a biofilm in a microbial fuel cell (MFC), and more easily applied dip-and-blot coating reduced voltage by only 11% in a microbial electrolysis cell (MEC). This latex immobilization procedure will enable future testing of single cells for exoelectrogenic activity on electrodes in BESs.

  15. Immobilization of anode-attached microbes in a microbial fuel cell.

    KAUST Repository

    Wagner, Rachel C; Porter-Gill, Sikandar; Logan, Bruce E

    2012-01-01

    Current-generating (exoelectrogenic) bacteria in bioelectrochemical systems (BESs) may not be culturable using standard in vitro agar-plating techniques, making isolation of new microbes a challenge. More in vivo like conditions are needed where bacteria can be grown and directly isolated on an electrode. While colonies can be developed from single cells on an electrode, the cells must be immobilized after being placed on the surface. Here we present a proof-of-concept immobilization approach that allows exoelectrogenic activity of cells on an electrode based on applying a layer of latex to hold bacteria on surfaces. The effectiveness of this procedure to immobilize particles was first demonstrated using fluorescent microspheres as bacterial analogs. The latex coating was then shown to not substantially affect the exoelectrogenic activity of well-developed anode biofilms in two different systems. A single layer of airbrushed coating did not reduce the voltage produced by a biofilm in a microbial fuel cell (MFC), and more easily applied dip-and-blot coating reduced voltage by only 11% in a microbial electrolysis cell (MEC). This latex immobilization procedure will enable future testing of single cells for exoelectrogenic activity on electrodes in BESs.

  16. Immobilized cell technology in beer brewing: Current experience and results

    Directory of Open Access Journals (Sweden)

    Leskošek-Čukalov Ida J.

    2005-01-01

    Full Text Available Immobilized cell technology (ICT has been attracting continual attention in the brewing industry over the past 30 years. Some of the reasons are: faster fermentation rates and increased volumetric productivity, compared to those of traditional beer production based on freely suspended cells, as well as the possibility of continuous operation. Nowadays, ICT technology is well established in secondary fermentation and alcohol- free and low-alcohol beer production. In main fermentation, the situation is more complex and this process is still under scrutiny on both the lab and pilot levels. The paper outlines the most important ICT processes developed for beer brewing and provides an overview of carrier materials, bioreactor design and examples of their industrial applications, as well as some recent results obtained by our research group. We investigated the possible applications of polyvinyl alcohol in the form of LentiKats®, as a potential porous matrices carrier for beer fermentation. Given are the results of growth studies of immobilized brewer's yeast Saccharomyces uvarum and the kinetic parameters obtained by using alginate microbeads with immobilized yeast cells and suspension of yeast cells as controls. The results indicate that the immobilization procedure in LentiKat® carriers has a negligible effect on cell viability and growth. The apparent specific growth rate of cells released in medium was comparable to that of freely suspended cells, implying preserved cell vitality. A series of batch fermentations performed in shaken flasks and an air-lift bioreactor indicated that the immobilized cells retained high fermentation activity. The full attenuation in green beer was reached after 48 hours in shaken flasks and less than 24 hours of fermentation in gas-lift bioreactors.

  17. The single-cell gel electrophoresis assay to determine apoptosis ...

    African Journals Online (AJOL)

    When the frequency of appearance of apoptotic cells following was observed over a period of time, there was a significant increase in appearance of apoptosis when using single cell gel electrophoresis assay. The present report demonstrates that the characteristic pattern of apoptotic comets detected by the comet assay ...

  18. Physico-chemical characteristics of immobilized polygalacturonase ...

    African Journals Online (AJOL)

    Polygalacturonase (PG) was isolated from Aspergillus niger (A. niger) (SA6), partially purified, characterized and immobilized by entrapment using calcium alginate. The polygalacturonase showed two bands on sodium dodecyl sulfate polyacryamide gel electrophoresis (SDS-PAGE) suggesting an “endo and exo” ...

  19. Micromagnetic Cancer Cell Immobilization and Release for Real-Time Single Cell Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jaiswal, Devina; Rad, Armin Tahmasbi [Department of Biomedical Engineering, University of Connecticut, Storrs, CT, 06269 (United States); Nieh, Mu-Ping [Department of Biomedical Engineering, University of Connecticut, Storrs, CT, 06269 (United States); Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, CT 06269 (United States); Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, CT 06269 (United States); Claffey, Kevin P. [Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030 (United States); Hoshino, Kazunori, E-mail: hoshino@engr.uconn.edu [Department of Biomedical Engineering, University of Connecticut, Storrs, CT, 06269 (United States)

    2017-04-01

    Understanding the interaction of live cells with macromolecules is crucial for designing efficient therapies. Considering the functional heterogeneity found in cancer cells, real-time single cell analysis is necessary to characterize responses. In this study, we have designed and fabricated a microfluidic channel with patterned micromagnets which can temporarily immobilize the cells during analysis and release them after measurements. The microchannel is composed of plain coverslip top and bottom panels to facilitate easy microscopic observation and undisturbed application of analytes to the cells. Cells labeled with functionalized magnetic beads were immobilized in the device with an efficiency of 90.8±3.6%. Since the micromagnets are made of soft magnetic material (Ni), they released cells when external magnetic field was turned off from the channel. This allows the reuse of the channel for a new sample. As a model drug analysis, the immobilized breast cancer cells (MCF7) were exposed to fluorescent lipid nanoparticles and association and dissociation were measured through fluorescence analysis. Two concentrations of nanoparticles, 0.06 µg/ml and 0.08 µg/ml were tested and time lapse images were recorded and analyzed. The microfluidic device was able to provide a microenvironment for sample analysis, making it an efficient platform for real-time analysis.

  20. Immobilization of yeast cells with ionic hydrogel produced by radiation polymerization

    International Nuclear Information System (INIS)

    Lu Zhaoxin; Fujimura, T.

    1990-01-01

    The mixture of an ionic monomer of 2-acrylamido 2-methylpropane-sulfonic acid and a series of polyethylene glycol dimethacrylate monomer were polymerized at-78 deg C with 60 Co γ-rays and were used for immobilization of yeast cells. The immobilized yeast cells with these carriers had higher ethanol productivity than that without any carriers. The yield of ethanol with poly TBAS-14G carrier was the highest, and increased by 3.5 times compared with the free yeast cells. It was found that the ethanol yield increased with the increase of the glycol number in polyethylene glycol dimethacrylate. The state of the immobilized cells was observed with microscope and it was found that the difference in the ethanol productivity was mainly due to the difference in the internal structure and the properties of polymer carrier. It was considered that the polymer carrier had a proper hydrophilicity, swelling ability, cation in the surface and porousity in the internal structure for immobilizing yeast cells

  1. Ethanol production from concentrated food waste hydrolysates with yeast cells immobilized on corn stalk

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Shoubao [Huainan Normal Univ., Anhui (China). School of Life Science; Chen, Xiangsong; Wu, Jingyong; Wang, Pingchao [Chinese Academy of Sciences, Hefei (China). Key Lab. of Ion Beam Bio-engineering of Inst. of Plasma Physics

    2012-05-15

    The aim of the present study was to examine ethanol production from concentrated food waste hydrolysates using whole cells of S. cerevisiae immobilized on corn stalks. In order to improve cell immobilization efficiency, biological modification of the carrier was carried out by cellulase hydrolysis. The results show that proper modification of the carrier with cellulase hydrolysis was suitable for cell immobilization. The mechanism proposed, cellulase hydrolysis, not only increased the immobilized cell concentration, but also disrupted the sleek surface to become rough and porous, which enhanced ethanol production. In batch fermentation with an initial reducing sugar concentration of 202.64 {+-} 1.86 g/l, an optimal ethanol concentration of 87.91 {+-} 1.98 g/l was obtained using a modified corn stalk-immobilized cell system. The ethanol concentration produced by the immobilized cells was 6.9% higher than that produced by the free cells. Ethanol production in the 14th cycle repeated batch fermentation demonstrated the enhanced stability of the immobilized yeast cells. Under continuous fermentation in an immobilized cell reactor, the maximum ethanol concentration of 84.85 g/l, and the highest ethanol yield of 0.43 g/g (of reducing sugar) were achieved at hydraulic retention time (HRT) of 3.10 h, whereas the maximum volumetric ethanol productivity of 43.54 g/l/h was observed at a HRT of 1.55 h. (orig.)

  2. Immobilization of microbial cells on cellulose-polymer surfaces by radiation polymerization

    International Nuclear Information System (INIS)

    Kumakura, M.; Kaetsu, I.

    1983-01-01

    Streptomyces phaeochromogens cells were immobilized on cellulose-polymer surfaces by radiation polymerization using hydrophilic monomers and paper. The enzyme activity of immobilized cell sheets was higher than that of immobilized cell composites obtained by the usual radiation polymerization technique. The enzyme activity of the sheets was affected by monomer concentration, the thickness of paper, and the degree of polymerization of paper. The copolymerization of hydroxyethyl methacrylate and methoxytetraethyleneglycol methacrylate in the sheets led to a further increase of the enzyme activity due to the increase of the hydrophilicity of the polymer matrix. The Michaelis constant of the sheets from low monomer concentration was close to that of intact cells

  3. A study on immobilized ethanol yeast cells by radiation technique

    International Nuclear Information System (INIS)

    Li Zhengkui; Zhang Bosen

    1994-01-01

    Hydrophilic monomer 2-hydroxyethyl acrylate (HEA) and a series of polyethylene glycol dimethacrylate monomers were copolymerized by radiation technique at low temperature (-78 degree C) and hydrophilic hydrogels were obtained. The immobilization of yeast cells with these copolymer carriers led to a higher ethanol productivity than free cells. Of all copolymer carriers, the ethanol yield with poly (HEA-14 G) was the highest, about 2.45 times as high as that of free yeast cells. In addition, the ethanol productivity of 12 batch repeated reactions with poly (HEA-14G) carrier was all higher than that of free yeast cells. The ethanol productivity of immobilized yeast cells was dependent on the proportion of hydrophilic monomer to other monomers in copolymer systems, the chain length of the bifunctional monomer, the degree of hydration of copolymer carriers, the structure of copolymer carriers and porosity in the internal structure of carriers. The ethanol yield of immobilized cells depended on swelling ability and porosity of copolymer carriers

  4. Enhanced degradation of 2-nitrotoluene by immobilized cells of Micrococcus sp. strain SMN-1.

    Science.gov (United States)

    Mulla, Sikandar I; Talwar, Manjunatha P; Bagewadi, Zabin K; Hoskeri, Robertcyril S; Ninnekar, Harichandra Z

    2013-02-01

    Nitrotoluenes are the toxic pollutants of the environment because of their large scale use in the production of explosives. Biodegradation of such chemicals by microorganisms may provide an effective method for their detoxification. We have studied the degradation of 2-nitrotoluene by cells of Micrococcus sp. strain SMN-1 immobilized in various matrices such as polyurethane foam (PUF), sodium alginate (SA), sodium alginate-polyvinyl alcohol (SA-PVA), agar and polyacrylamide. The rate of degradation of 15 and 30 mM 2-nitrotoluene by freely suspended cells and immobilized cells in batches and fed-batch with shaken cultures were compared. The PUF-immobilized cells achieved higher degradation of 15 and 30 mM 2-nitrotoluene than freely suspended cells and the cells immobilized in SA-PVA, polyacrylamide, SA and agar. The PUF-immobilized cells could be reused more than 24 cycles without loosing their degradation capacity and showed more tolerance to pH and temperature changes than freely suspended cells. These results revealed the enhanced rate of degradation of 2-nitrotoluene by PUF-immobilized cells of Micrococcus sp. strain SMN-1. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Enzyme production in immobilized Trichoderma reesei cells with hydrophobic polymers prepared by radiation polymerization method

    International Nuclear Information System (INIS)

    Luzhao Xin; Kumakura, Minoru; Kaetsu, Isao

    1993-01-01

    Trichoderma reesei cells were immobilized on paper covered with hydrophobic monomer, trimethylpropane triacrylate by radiation polymerization. The effect of immobilization condition on enzyme productivity was studied by measuring filter paper and cellobiose activity. The cells were adhered and grew on the surface of the carrier with the polymer giving high enzyme productivity in the immobilized cells in comparison with the free cells. Optimum concentration and volume of the coating monomer for the preparation of the immobilized cells were obtained. (author)

  6. Immobilization of chlorine dioxide modified cells for uranium absorption

    International Nuclear Information System (INIS)

    He, Shengbin; Ruan, Binbiao; Zheng, Yueping; Zhou, Xiaobin; Xu, Xiaoping

    2014-01-01

    There has been a trend towards the use of microorganisms to recover metals from industrial wastewater, for which various methods have been reported to be used to improve microorganism adsorption characteristics such as absorption capacity, tolerance and reusability. In present study, chlorine dioxide(ClO 2 ), a high-efficiency, low toxicity and environment-benign disinfectant, was first reported to be used for microorganism surface modification. The chlorine dioxide modified cells demonstrated a 10.1% higher uranium adsorption capacity than control ones. FTIR analysis indicated that several cell surface groups are involved in the uranium adsorption and cell surface modification. The modified cells were further immobilized on a carboxymethylcellulose (CMC) matrix to improve their reusability. The cell-immobilized adsorbent could be employed either in a high concentration system to move vast UO 2 2+ ions or in a low concentration system to purify UO 2 2+ contaminated water thoroughly, and could be repeatedly used in multiple adsorption-desorption cycles with about 90% adsorption capacity maintained after seven cycles. - Highlights: • Chlorine dioxide was first reported to be used for microorganism surface modification. • The chlorine dioxide modified cells demonstrated a 10.1% higher uranium adsorption capacity than control ones. • The chlorine dioxide modified cells were further immobilized by carboxymethylcellulose to improve their reusability

  7. Immobilization of trichoderma REESEI (QM 9414) cells with paper covered with ionic copolymer by radiation polymerization

    International Nuclear Information System (INIS)

    Lu Zhaoxin

    1992-01-01

    Cationic-hydrophobic copolymer and anionic-hydrophobic copolymer was covered onto surface of paper by radiation polymerization. The paper covered with ionic copolymer was used as carrier of immobilizing Trichoderma reesei cells. Results showed that the cells were immobilized firmly on the carriers and not dislocated from the carriers by shaking. All of FPA of the cells immobilized with the carriers covered with cationic copolymer were higher than that of un-immobilized free cells. The carriers covered with anionic copolymer showed good effect on immobilization of the cells. The weight of immobilized cells increase as increasing the component of DEAEMA in poly (DEAEMA-ATMPT) or decreasing the component of AA in poly (AA-ATMPT). It also increase with the increase of water absorption in poly (DEAEMA-ATMPT) or decrease of water absorption in poly (AA-ATMPT). It shows the static interaction play an important role in the immobilization of cells with ionic copolymer materials

  8. Electrophoresis forum '80

    International Nuclear Information System (INIS)

    Radola, B.J.

    1980-01-01

    In this volume the contributions of the electrophoresis meeting are presented in a short term form. The main topics are gel-electrophoresis, ultra thin film isoelectric focusing, one- and two-dimensional electrophoresis, electrophoretical separation techniques, electric focusing (for phorensic studies), substrate free and substrate electrophoresis. In the poster session of this meeting subjects such as (ultra) thin film isoelectric focusing, identification of radioactive proteins, labelling of cell surfaces, autoradiography and 3 H-labelled proteins. Separate abstracts were prepared for 4 papers in this report. (HK) [de

  9. Continuous ethanol production from Jerusalem artichokes stalks using immobilized cells of Kluyveromyces marxianus

    Energy Technology Data Exchange (ETDEWEB)

    Bajpai, P.; Margaritis, A.

    1986-01-01

    Continuous production of ethanol from the extract of Jerusalem artichoke stalks was investigated in a packed bed bioreactor using Kluyveromyces marxianus cells immobilized in calcium alginate gel beds. Maximum conversion of the sugars to ethanol was achieved with a yield of about 98% of the theoretical. Volumetric ethanol productivities of 102 grams of ethanol per litre per hour and 92 grams ethanol per liter per hour were obtained at 87% and 90% conversion respectively for an inlet substrate concentration of 100 gram sugars per liter. The maximum specific ethanol production rate and maximum specific total sugar uptake rate of the immobilized cells were found to be 0.96 gram ethanol per gram immobilized cells per hour and 2.06 gram sugars per gram immobilized cells per hour respectively. The immobilized cell bioreactor was run continuously at a dilution rate of 2.12 per hour for 30 days which resulted in a loss of 30% of the original activity. The half life of the bioreactor was estimated to be about 56 days.

  10. Effects of RGD immobilization on light-induced cell sheet detachment from TiO{sub 2} nanodots films

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Kui; Wang, Tiantian [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027 (China); Yu, Mengliu [The Affiliated Stomatologic Hospital, Zhejiang University, Hangzhou 310003 (China); The First Affiliated Hospital of Medical College, Zhejiang University, Hangzhou, 310003 (China); Wan, Hongping [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027 (China); Lin, Jun [The First Affiliated Hospital of Medical College, Zhejiang University, Hangzhou, 310003 (China); Weng, Wenjian, E-mail: wengwj@zju.edu.cn [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027 (China); The Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050 (China); Wang, Huiming, E-mail: hmwang1960@hotmail.com [The Affiliated Stomatologic Hospital, Zhejiang University, Hangzhou 310003 (China); The First Affiliated Hospital of Medical College, Zhejiang University, Hangzhou, 310003 (China)

    2016-06-01

    Light-induced cell detachment is reported to be a safe and effective cell sheet harvest method. In the present study, the effects of arginine–glycine–aspartic acid (RGD) immobilization on cell growth, cell sheet construction and cell harvest through light illumination are investigated. RGD was first immobilized on TiO{sub 2} nanodots films through simple physical adsorption, and then mouse pre-osteoblastic MC3T3-E1 cells were seeded on the films. It was found that RGD immobilization promoted cell adhesion and proliferation. It was also observed that cells cultured on RGD immobilized films showed relatively high level of pan-cadherin. Cells harvested with ultraviolet illumination (365 nm) showed good viability on both RGD immobilized and unmodified TiO{sub 2} nanodot films. Single cell detachment assay showed that cells detached more quickly on RGD immobilized TiO{sub 2} nanodot films. That could be ascribed to the RGD release after UV365 illumination. The current study demonstrated that RGD immobilization could effectively improve both the cellular responses and light-induced cell harvest. - Highlights: • RGD immobilization on TiO{sub 2} nanodots film favors light-induced cell sheet detachment. • Physically adsorbed RGD detaches from the film through ultraviolet illumination. • RGD detachment promotes cells and cell sheets detachment.

  11. Immobilization of microorganisms. Part 1. Preparation of immobilized Lactobacillus bulgaricus

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K H

    1981-01-01

    The immobilization of Lactobacillus bulgaricus on polyacrylamide and on alginate beads was investigated. The most active immobilized cells were obtained by entrapment in Ca alginate beads. These immobilized microbial cells, when introduced into 4.5% lactose solution and whey solution showed maximum relative activity of 28% for lactose and 18% for whey compared to free cells.

  12. Comparative study on antibody immobilization strategies for efficient circulating tumor cell capture.

    Science.gov (United States)

    Ates, Hatice Ceren; Ozgur, Ebru; Kulah, Haluk

    2018-03-23

    Methods for isolation and quantification of circulating tumor cells (CTCs) are attracting more attention every day, as the data for their unprecedented clinical utility continue to grow. However, the challenge is that CTCs are extremely rare (as low as 1 in a billion of blood cells) and a highly sensitive and specific technology is required to isolate CTCs from blood cells. Methods utilizing microfluidic systems for immunoaffinity-based CTC capture are preferred, especially when purity is the prime requirement. However, antibody immobilization strategy significantly affects the efficiency of such systems. In this study, two covalent and two bioaffinity antibody immobilization methods were assessed with respect to their CTC capture efficiency and selectivity, using an anti-epithelial cell adhesion molecule (EpCAM) as the capture antibody. Surface functionalization was realized on plain SiO 2 surfaces, as well as in microfluidic channels. Surfaces functionalized with different antibody immobilization methods are physically and chemically characterized at each step of functionalization. MCF-7 breast cancer and CCRF-CEM acute lymphoblastic leukemia cell lines were used as EpCAM positive and negative cell models, respectively, to assess CTC capture efficiency and selectivity. Comparisons reveal that bioaffinity based antibody immobilization involving streptavidin attachment with glutaraldehyde linker gave the highest cell capture efficiency. On the other hand, a covalent antibody immobilization method involving direct antibody binding by N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC)-N-hydroxysuccinimide (NHS) reaction was found to be more time and cost efficient with a similar cell capture efficiency. All methods provided very high selectivity for CTCs with EpCAM expression. It was also demonstrated that antibody immobilization via EDC-NHS reaction in a microfluidic channel leads to high capture efficiency and selectivity.

  13. Immobilization of cellulose producing cells (sporotrichum cellulophilum) using irradiated rice husk as a substrate

    International Nuclear Information System (INIS)

    Lina, M.R.; Tamada, M.; Kumakura, M.

    1991-01-01

    An experiment to study the effect of irradiated rice husk as a substrate on cellulase production of free and immobilized cells of S. cellulophium was carried out. Radiation pretreatment of rice husk was done using electron beam accelerator (Dynamitron IEA 3000-25,2), with doses of 0, 0.2, 0.4, 0.6, 0.8, and 1.0 MGy. The substrate used in cellulase production of free and immobilized cells were cellulose powder as a standard, and 1.0 MGy irradiated rice husk. Concentrations of cellulose powder for free and immobilized cells were 1, 2, 3, 5, and 8% (w/v). Irradiated rice husk concentrations for free cells were 3, 6, 9, 15, and 24% (w/v), whereas for immobilized cells were 3, 6, and 9% (w/v). Results showed that glucose concentration in 1.0 MGy irradiated rice husk was the highest of all irradiated and unirradiated rice husks. The GPA (glucose production activity) values used of free immobilized cells of S. cellulophium in medium containing 1.0 MGy irradiated rice husk were about 50% lower than in cellulose powder medium. Cellulase solution resulted by immobilized cells, either in cellulose powder or in irradiated rice husk media, were clear and did not contain mycelium. (authors). 7 refs, 7 figs

  14. A study of ethanol production of yeast cells immobilized with polymer carrier produced by radiation polymerization

    International Nuclear Information System (INIS)

    Lu Zhaoxin; Fujimura, Takashi

    1993-01-01

    Polymer carriers, poly(hydroxyethyl acrylate(HEA)-methoxy polyethylene glycol methylacrylate (M-23G)) and poly(hydroxyethyl acrylate(HEA)-glycidyl methylacrylate (GMA)) used for the immobilization of yeast cells were prepared by radiation polymerization at low temperature. Yeast cells were immobilized through adhesion and multiplication of yeast cells. The ethanol productivity of immobilized yeast cells with these carriers was related to the monomer composition of polymers and the optimum monomer composition was 20%:10% in poly(HEA-M-23G) and 17%:6% in poly(HEA-GMA). In this case, the ethanol productivity of immobilized yeast cells was about 4 times that of cells in free system. The relationship between the activity of immobilized yeast cells and the water content of the polymer carrier were also discussed. (author)

  15. Study on immobilized yeast cells with hydrophilic polymer carrier by radiation-induced copolymerization

    International Nuclear Information System (INIS)

    Li Zhengkui; Zhang Bosen

    1993-01-01

    Various kinds of monomers 2-hydroxyethyl methacrylate (HEMA), 2-hydroxyethyl acrylate (HEA), hydroxypropyl methacrylate (HPMA) and methoxy polyethylene glycol methylacrylate (M-23G) are copolymerized by radiation technique at low temperature (-78 degree C) and several kinds of copolymer carriers were obtained. Yeast cells are immobilized through adhesion and multiplication of yeast cells themselves on these carriers. The ethanol productivity of immobilized yeast cells with these carriers was related to the monomer composition and water content of copolymer carriers and the optimum monomer composition was 20%:10% in poly (HEA-M23G). In this case, the ethanol productivity of immobilized yeast cells was 26 mg/(ml · h), which was 4 times as high as that of free cells. Effect of adding crosslinking reagent (4G) in lower monomer composition of poly(HEA-M23G) on the ethanol productivity of immobilized cells was better than that in higher one in this work

  16. Cells immobilized on patterns printed in DNA by an inkjet printer.

    Science.gov (United States)

    Sakurai, Kengo; Teramura, Yuji; Iwata, Hiroo

    2011-05-01

    The ability to two-dimensionally align various kinds of cells freely onto substrate would be a useful tool for analysis of cell-cell interactions. In this study, we aimed to establish a method for attaching cells to the substrate, in which the pattern is drawn by an inkjet printer. Poly-deoxyribonucleic acid (DNA) was immobilized onto the cell surface by use of DNA-conjugated poly(ethylene) glycol-phospholipid (DNA-PEG-lipid), which is the amphiphilic conjugate of PEG-lipid and single-stranded DNA. The surface of the substrate was then modified with the complementary DNA using an inkjet printer. Finally, DNA-immobilized cells were attached onto the substrate through DNA hybridization. The use of the inkjet printer enabled us to draw the DNA pattern accurately on the substrate with a resolution of a few hundred micrometers. DNA-immobilized cells could be attached precisely along the DNA pattern on the substrate. In addition, various kinds of cells could be attached simultaneously by using various sequences of DNA. Our technique is promising for analysis of cell-cell interactions and differentiation induction in stem cell research. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Investigating the feasibility of stem cell enrichment mediated by immobilized selectins.

    Science.gov (United States)

    Charles, Nichola; Liesveld, Jane L; King, Michael R

    2007-01-01

    Hematopoietic stem cell therapy is used to treat both malignant and non-malignant diseases, and enrichment of the hematopoietic stem and progenitor cells (HSPCs) has the potential to reduce the likelihood of graft vs host disease or relapse, potentially fatal complications associated with the therapy. Current commercial HSPC isolation technologies rely solely on the CD34 surface marker, and while they have proven to be invaluable, they can be time-consuming with variable recoveries reported. We propose that selectin-mediated enrichment could prove to be a quick and effective method for recovering HSPCs from adult bone marrow (ABM) on the basis of differences in rolling velocities and independently of CD34 expression. Purified CD34+ ABM cells and the unselected CD34- ABM cells were perfused over immobilized P-, E-, and L-selectin-IgG at physiologic wall shear stresses, and rolling velocities and cell retention data were collected. CD34+ ABM cells generally exhibited lower rolling velocities and higher retention than the unselected CD34- ABM cells on all three selectins. For initial CD34+ ABM cell concentrations ranging from 1% to 5%, we predict an increase in purity ranging from 5.2% to 36.1%, depending on the selectin used. Additionally, selectin-mediated cell enrichment is not limited to subsets of cells with inherent differences in rolling velocities. CD34+ KG1a cells and CD34- HL60 cells exhibited nearly identical rolling velocities on immobilized P-selectin-IgG over the entire range of shear stresses studied. However, when anti-CD34 antibody was co-immobilized with the P-selectin-IgG, the rolling velocity of the CD34+ KG1a cells was significantly reduced, making selectin-mediated cell enrichment a feasible option. Optimal cell enrichment in immobilized selectin surfaces can be achieved within 10 min, much faster than most current commercially available systems.

  18. Indirect immobilized Jagged1 suppresses cell cycle progression and induces odonto/osteogenic differentiation in human dental pulp cells.

    Science.gov (United States)

    Manokawinchoke, Jeeranan; Nattasit, Praphawi; Thongngam, Tanutchaporn; Pavasant, Prasit; Tompkins, Kevin A; Egusa, Hiroshi; Osathanon, Thanaphum

    2017-08-31

    Notch signaling regulates diverse biological processes in dental pulp tissue. The present study investigated the response of human dental pulp cells (hDPs) to the indirect immobilized Notch ligand Jagged1 in vitro. The indirect immobilized Jagged1 effectively activated Notch signaling in hDPs as confirmed by the upregulation of HES1 and HEY1 expression. Differential gene expression profiling using an RNA sequencing technique revealed that the indirect immobilized Jagged1 upregulated genes were mainly involved in extracellular matrix organization, disease, and signal transduction. Downregulated genes predominantly participated in the cell cycle, DNA replication, and DNA repair. Indirect immobilized Jagged1 significantly reduced cell proliferation, colony forming unit ability, and the number of cells in S phase. Jagged1 treated hDPs exhibited significantly higher ALP enzymatic activity, osteogenic marker gene expression, and mineralization compared with control. Pretreatment with a γ-secretase inhibitor attenuated the Jagged1-induced ALP activity and mineral deposition. NOTCH2 shRNA reduced the Jagged1-induced osteogenic marker gene expression, ALP enzymatic activity, and mineral deposition. In conclusion, indirect immobilized Jagged1 suppresses cell cycle progression and induces the odonto/osteogenic differentiation of hDPs via the canonical Notch signaling pathway.

  19. Immobilization of yeast cells with ionic hydrogel carriers by adhesion-multiplication.

    Science.gov (United States)

    Zhaoxin, L; Fujimura, T

    2000-12-01

    The mixture of an ionic monomer, 2-acrylamido 2-methylpropanesulfonic acid (TBAS), and a series of poly(ethylene glycol) dimethacrylate (nG) monomers were copolymerized with 60Co gamma-rays, and the produced ionic hydrogel polymers were used for immobilization of yeast cells. The cells were adhered onto the surface of the hydrogel polymers and intruded into the interior of the polymers with growing. The immobilized yeast cells with these hydrogel polymers had higher ethanol productivity than that of free cells. The yield of ethanol with poly(TBAS-14G) carrier was the highest and increased by 3.5 times compared to the free cells. It was found that the ethanol yield increased with the increase of glycol number in poly(ethylene glycol) dimethacrylate. The state of the immobilized cells was observed with microscope, and it was also found that the difference in the ethanol productivity is mainly due to the difference in the internal structure and properties of polymer carrier, such as surface charge, hydrophilicity, and swelling ability of polymer carrier.

  20. Radiobiological study on DNA strand breaks and repair using single cell gel electrophoresis

    International Nuclear Information System (INIS)

    Ikushima, Takaji

    1994-01-01

    Single cell gel electrophoresis (SCGE) provides a novel method to measure DNA damage in individual cells and more importantly, to assess heterogeneity in response within a mixed population of cells. Cells embedded in agarose are lysed, subjected to electrophoresis, stained with a fluorescent DNA-specific dye, and viewed under a fluorescence microscope. Damaged cells display 'comets', broken DNA migrating farther to the anode in the electric field. We have previously used this technique to quantify DNA damage induced by moderate doses of low and high LET radiations in cultured Chinese hamster cells. The assay has been optimized in terms of lysing and electrophoresis conditions, and applied to analyse the DNA strand breaks, their repair kinetics and heterogeneity in response in individual Chinese hamster cells exposed to gamma-rays, and to KUR thermal neutrons with and without 10 B or to KEK PF monochromatic soft X-rays as well as to a radio-mimetic agent, neocarzinostatin. The DNA double-strand breaks induced by boron-neutron captured reactions were repaired at a slower rate, but a heterogeneity in response might not contribute to the difference. The neocarzinostatin-induced DNA damage were efficiently repaired in a dose-dependent fashion. The initial amount of gamma-ray induced DNA double-strand breaks was not significantly altered in cells pre-exposed to very low adapting dose. (author)

  1. Fabrication of Aligned Carbon Nanotube/Polycaprolactone/Gelatin Nanofibrous Matrices for Schwann Cell Immobilization

    Directory of Open Access Journals (Sweden)

    Shiao-Wen Tsai

    2014-01-01

    Full Text Available In this study, we utilized a mandrel rotating collector consisting of two parallel, electrically conductive pieces of tape to fabricate aligned electrospun polycaprolactone/gelatin (PG and carbon nanotube/polycaprolactone/gelatin (PGC nanofibrous matrices. Furthermore, we examined the biological performance of the PGC nanofibrous and film matrices using an in vitro culture of RT4-D6P2T rat Schwann cells. Using cell adhesion tests, we found that carbon nanotube inhibited Schwann cell attachment on PGC nanofibrous and film matrices. However, the proliferation rates of Schwann cells were higher when they were immobilized on PGC nanofibrous matrices compared to PGC film matrices. Using western blot analysis, we found that NRG1 and P0 protein expression levels were higher for cells immobilized on PGC nanofibrous matrices compared to PG nanofibrous matrices. However, the carbon nanotube inhibited NRG1 and P0 protein expression in cells immobilized on PGC film matrices. Moreover, the NRG1 and P0 protein expression levels were higher for cells immobilized on PGC nanofibrous matrices compared to PGC film matrices. We found that the matrix topography and composition influenced Schwann cell behavior.

  2. Studies on lectins. XXXII. Application of affinity electrophoresis to the study of the interaction of lectins and their derivatives with sugars.

    Science.gov (United States)

    Horejsí, V; Tichá, M; Kocourek, J

    1977-09-29

    Affinity electrophoresis was used to study the sugar binding heterogeneity of lectins or their derivatives. Commercial and demetallized preparations of concanavalin A could be resolved by affinity electrophoresis into three components with different affinity to immobilized sugar. Similarly the Vicia cracca lectin obtained by affinity chromatography behaved on affinity gels as a mixture of active and inactive molecular species. Affinity electrophoresis has shown that the nonhemagglutinating acetylated lentil lectin and photo-oxidized or sulfenylated pea lectin retain their sugar binding properties; dissociation constants of saccharide complexes of these derivatives are similar to those of native lectins. The presence of specific immobilized sugar in the affinity gel improved the resolution of isolectins from Dolichos biflorus and Ricinus communis seeds.

  3. Hexavalent chromate reduction during growth and by immobilized cells of arthrobacter sp. suk 1205

    International Nuclear Information System (INIS)

    Dey, S.; Paul, A.K.

    2017-01-01

    The chromate reducing actinomycetes, Arthrobacter sp. SUK 1205, isolated from chromite mine overburden of Odisha, India exhibited significant chromate reduction during growth with characteristic formation of pale green insoluble precipitate. Reduction of chromate increased with increase in inoculum density but the reduction potential declined as and when Cr(VI) concentration in the medium was increased. Chromate reducing efficiency was promoted when glycerol and glucose were used as electron donors and pH and temperature were maintained at 7.0 and 35 degree C, respectively. The reduction process was inhibited by several metal ions and metabolic inhibitors but not by Cu(II), Mn(II) and DNP. Among the matrices tested for whole cell immobilization, Ca-alginate immobilized whole cells were found to be most effective and were comparable with non-immobilized cells. Minimal salts (MS) medium was the most effective base for Cr(VI) reduction studies with immobilized cells. Under such conditions, the immobilized cells retained their enzymatic activity at least for 4 consecutive cycles indicating the potential of Arthrobacter sp. SUK 1205 in bioremediation of environmental chromium pollution. (author)

  4. Co-immobilization of active antibiotics and cell adhesion peptides on calcium based biomaterials.

    Science.gov (United States)

    Palchesko, Rachelle N; Buckholtz, Gavin A; Romeo, Jared D; Gawalt, Ellen S

    2014-07-01

    Two bioactive molecules with unrelated functions, vancomycin and a cell adhesion peptide, were immobilized on the surface of a potential bone scaffold material, calcium aluminum oxide. In order to accomplish immobilization and retain bioactivity three sequential surface functionalization strategies were compared: 1.) vancomycin was chemically immobilized before a cell adhesion peptide (KRSR), 2.) vancomycin was chemically immobilized after KRSR and 3.) vancomycin was adsorbed after binding the cell adhesion peptide. Both molecules remained on the surface and active using all three reaction sequences and after autoclave sterilization based on osteoblast attachment, bacterial turbidity and bacterial zone inhibition test results. However, the second strategy was superior at enhancing osteoblast attachment and significantly decreasing bacterial growth when compared to the other sequences. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Ethanol fermentation of molasses by Saccharomyces cerevisiae cells immobilized onto sugar beet pulp

    Directory of Open Access Journals (Sweden)

    Vučurović Vesna M.

    2012-01-01

    Full Text Available Natural adhesion of Saccharomyces cerevisiae onto sugar beet pulp (SBP is a very simple and cheap immobilization method for retaining high cells density in the ethanol fermentation system. In the present study, yeast cells were immobilized by adhesion onto SBP suspended in the synthetic culture media under different conditions such as: glucose concentration (100, 120 and 150 g/l, inoculum concentration (5, 10 and 15 g/l dry mass and temperature (25, 30, 35 and 40°C. In order to estimate the optimal immobilization conditions the yeast cells retention (R, after each immobilization experiment was analyzed. The highest R value of 0.486 g dry mass yeast /g dry mass SBP was obtained at 30°C, glucose concentration of 150 g/l, and inoculum concentration of 15 g/l. The yeast immobilized under these conditions was used for ethanol fermentation of sugar beet molasses containing 150.2 g/l of reducing sugar. Efficient ethanol fermentation (ethanol concentration of 70.57 g/l, fermentation efficiency 93.98% of sugar beet molasses was achieved using S. cerevisiae immobilized by natural adhesion on SBP. [Projekat Ministarstva nauke Republike Srbije, br. TR-31002

  6. Radiation pretreatment of cellulosic wastes and immobilization of cells producing cellulase for their conversion to glucose

    International Nuclear Information System (INIS)

    Kumakura, Minoru; Kaetsu, Isao

    1988-01-01

    Radiation pretreatment of cellulosic wastes such as saw dust and chaff was studied by using electron beam accelerator, in which irradiation effect was increased by increasing irradiation dose and dose rate, by after heating irradiated materials at 100∼140deg C, and by irradiation in the addition of alkaline solution. Trichoderma reesei cells producing cellulase were immobilized by using fibrous porous carrier obtained from radiation polymerization. The filter paper, cellobiose, and CMC activities in the immobilized growing cells were higher than those in free cells. The activity in the immobilized cells obtained with hydrophobic carrier was higher than that obtained with hydrophilic one. Durability of the immobilized cells was examined by repeated batch culture. It was found that the enzyme solution produced in the culture of the immobilized cells can hydrolyze effectively saw dust pretreated by radiation. (author)

  7. The application of single cell gel electrophoresis or comet assay to human monitoring studies

    Directory of Open Access Journals (Sweden)

    Valverde Mahara

    1999-01-01

    Full Text Available Objective. In the search of new human genotoxic biomarkers, the single cell gel electrophoresis assay has been proposed as a sensible alternative. Material and methods. This technique detects principally single strand breaks as well as alkali-labile and repair-retarded sites. Results. Herein we present our experience using the single cell gel electrophoresis assay in human population studies, both occupationally and environmentally exposed. Conclusions. We discuss the assay feasibility as a genotoxic biomarker.

  8. Electrophoresis-base dye adsorption into titanium dioxide film for dye sensitized solar cell application

    International Nuclear Information System (INIS)

    Ratno Nuryadi; Zico Alaia Akbar Junior; Lia Aprilia

    2010-01-01

    Dye Sensitized Solar Cell (DSSC) is one of renewable energy sources which has demanded a substitute non renewable energy sources. The most important factor influencing DSSC performance is dye adsorption into semiconductor nano-porous TiO 2 particles. The purpose of this work is to study the effect of dye eosin Y adsorption on DSSC characteristics by an electrophoresis method. As result, Open Circuit Voltage (V oc ) of DSSC increases as the applied voltage of electrophoresis increases. It is also found that the eosin Y absorbance at wavelength of around 500 nm increases when the electrophoresis voltage is increased. These results indicate that electrophoresis process plays an important role in dye adsorption. (author)

  9. A response calculus for immobilized T cell receptor ligands

    DEFF Research Database (Denmark)

    Andersen, P S; Menné, C; Mariuzza, R A

    2001-01-01

    determine the level of T cell activation. When fitted to T cell responses against purified ligands immobilized on plastic surfaces, the 2D-affinity model adequately simulated changes in cellular activation as a result of varying ligand affinity and ligand density. These observations further demonstrated...

  10. Development of High-Productivity Continuous Ethanol Production using PVA-Immobilized Zymomonas mobilis in an Immobilized-Cells Fermenter

    Directory of Open Access Journals (Sweden)

    Nurhayati Nurhayati

    2015-07-01

    Full Text Available Ethanol as one of renewable energy was being considered an excellent alternative clean-burning fuel to replace gasoline. Continuous ethanol fermentation systems had offered important economic advantages compared to traditional systems. Fermentation rates were significantly improved, especially when continuous fermentation was integrated with cell immobilization techniques to enrich the cells concentration in fermentor. Growing cells of Zymomonas mobilis immobilized in polyvinyl alcohol (PVA gel beads were employed in an immobilized-cells fermentor for continuous ethanol fermentation from glucose. The glucose loading, dilution rate, and cells loading were varied in order to determine which best condition employed in obtaining both high ethanol production and low residual glucose with high dilution rate. In this study, 20 g/L, 100 g/L, 125 g/L and 150 g/L of glucose concentration and 20% (w/v, 40% (w/v and 50% (w/v of cells loading were employed with range of dilution rate at 0.25 to 1 h-1. The most stable production was obtained for 25 days by employing 100 g/L of glucose loading. Meanwhile, the results also exhibited that 125 g/L of glucose loading as well as 40% (w/v of cells loading yielded high ethanol concentration, high ethanol productivity, and acceptable residual glucose at 62.97 g/L, 15.74 g/L/h and 0.16 g/L, respectively. Furthermore, the dilution rate of 4 hour with 100 g/L and 40% (w/v of glucose and cells loading was considered as the optimum condition with ethanol production, ethanol productivity and residual glucose obtained were 49.89 g/L, 12.47 g/L/h, and 2.04 g/L, respectively. This recent study investigated ethanol inhibition as well. The present research had proved that high sugar concentration was successfully converted to ethanol. These achieved results were promising for further study.

  11. Hydrolysis of fish protein by Bacillus megaterium cells immobilized in radiation induced polymerized wood

    International Nuclear Information System (INIS)

    Ghosh, S.; Alur, M.D.; Nerkar, D.P.

    1992-01-01

    The immobilization of Bacillus megaterium cells in radiation-induced polymerized wood was studied for hydrolysis of trash fish protein. The optimum conditions and reaction kinetics for hydrolysis of protein by free and immobilized cells were found to be similar. Maximum hydrolysis occurred at 50 o C and at pH 7.5 with 15-20% (w/v) of immobilized matrix. The soluble content of the resultant hydrolysate about 2.4% (w/v). (author). 10 refs., 4 figs

  12. Identification of proteins of human colorectal carcinoma cell line SW480 by two-dimensional electrophoresis and MALDI-TOF mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    Ying-Tao Zhang; Yi-Ping Geng; Le Zhou; Bao-Chang Lai; Lv-Sheng Si; Yi-Li Wang

    2005-01-01

    AIM: To conduct the proteomic analysis of human colorectal carcinoma cell line, SW480 by using two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption /ionization-time of flight mass spectrometry (MALDITOFMS).METHODS: The total proteins of human colorectal carcinoma cell line, SW480 were separated with 2-DE by using immobilized pH gradient strips and visualized by staining with silver nitrate. The gel images were acquired by scanner and 2-DE analysis software, Image Master 2D Elite. Nineteen distinct protein spots were excised from gel randomly and digested in gel by TPCK-trypsin. Mass analysis ofthe tryptic digest peptides mixture was performed by using MALDI-TOF MS. Peptide mass fingerprints (PMFs) obtained by the MALDI-TOF analysis were used to search NCBI,SWISS-PROT and MSDB databases by using Mascot software.RESULTS: PMF maps of all spots were obtained by MALDI-TOF MS and thirteen proteins were preliminarily identified.CONCLUSION: The methods of analysis and identification of protein spots of tumor cells in 2-DE gel with silver staining by MALDI-TOF MS derived PMF have been established.Protein expression profile of SW480 has been obtained.It is demonstrated that a combination of proteomics and cell culture is a useful approach to comprehend the process of colon carcinogenesis.

  13. Optimizing Immobilized Enzyme Performance in Cell-Free Environments to Produce Liquid Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Belfort, Georges [Rensselaer Polytechnic Inst., Troy, NY (United States). Dept. of Chemical and Biological Engineering; Grimaldi, Joseph J. [Rensselaer Polytechnic Inst., Troy, NY (United States). Dept. of Chemical and Biological Engineering

    2015-01-27

    Limitations on biofuel production using cell culture (Escherichia coli, Clostridium, Saccharomyces cerevisiae, brown microalgae, blue-green algae and others) include low product (alcohol) concentrations (≤0.2 vol%) due to feedback inhibition, instability of cells, and lack of economical product recovery processes. To overcome these challenges, an alternate simplified biofuel production scheme was tested based on a cell-free immobilized enzyme system. Using this cell free system, we were able to obtain about 2.6 times higher concentrations of iso-butanol using our non-optimized system as compared with live cell systems. This process involved two steps: (i) converts acid to aldehyde using keto-acid decarboxylase (KdcA), and (ii) produces alcohol from aldehyde using alcohol dehydrogenase (ADH) with a cofactor (NADH) conversion from inexpensive formate using a third enzyme, formate dehydrogenase (FDH). To increase stability and conversion efficiency with easy separations, the first two enzymes were immobilized onto methacrylate resin. Fusion proteins of labile KdcA (fKdcA) were expressed to stabilize the covalently immobilized KdcA. Covalently immobilized ADH exhibited long-term stability and efficient conversion of aldehyde to alcohol over multiple batch cycles without fusions. High conversion rates and low protein leaching were achieved by covalent immobilization of enzymes on methacrylate resin. The complete reaction scheme was demonstrated by immobilizing both ADH and fKdcA and using FDH free in solution. The new system without in situ removal of isobutanol achieved a 55% conversion of ketoisovaleric acid to isobutanol at a concentration of 0.5 % (v/v). Further increases in titer will require continuous removal of the isobutanol using our novel brush membrane system that exhibits a 1.5 fold increase in the separation factor of isobutanol from water versus that obtained for commercial silicone rubber membranes. These bio-inspired brush membranes are based on the

  14. The effect of cell immobilization on the antibacterial activity of Lactobacillus reuteri DPC16 cells during passage through a simulated gastrointestinal tract system.

    Science.gov (United States)

    Zhao, Qian; Maddox, Ian S; Mutukumira, Anthony; Lee, Sung Je; Shu, Quan

    2012-10-01

    Cell immobilization has the ability to influence the survival and functional characteristics of probiotic bacterial strains in harsh environments. This study investigated the effect of cell immobilization and passage through a simulated gastrointestinal tract (GI) on the antibacterial activity of Lactobacillus reuteri DPC16. Antibacterial activity, reuterin production and diol dehydratase activity were assayed in recovered isolates of L. reuteri that had been immobilized in Ca alginate-skim milk, and incubated in simulated GI fluids. Among all the recovered isolates tested, any that had undergone immobilization followed by immediate recovery of the cells without subsequent incubation in any fluids demonstrated the highest reuterin production, antimicrobial activity and diol dehydratase enzyme activity. L. reuteri DPC16 cells that had been immobilized, incubated in simulated GI fluids, and subsequently recovered from the beads often showed some loss of antimicrobial activity compared to the immobilized cells. The data confirm that the process of immobilization of L. reuteri in Ca alginate-skim milk, rather than the passage through simulated GI fluids, resulted in enhanced antibacterial activity. This is attributed to increased diol dehydratase activity, resulting in increased reuterin production.

  15. Production of tannase by the immobilized cells of Bacillus licheniformis KBR6 in Ca-alginate beads.

    Science.gov (United States)

    Mohapatra, P K D; Mondal, K C; Pati, B R

    2007-06-01

    The present study was aimed at finding the optimal conditions for immobilization of Bacillus licheniformis KBR6 cells in calcium-alginate (Ca-alginate) beads and determining the operational stability during the production of tannin-acyl-hydrolase (tannase) under semicontinous cultivation. The active cells of B. licheniformis KBR6 were immobilized in Ca-alginate and used for the production of tannase. The influence of alginate concentration (5, 10, 20 and 30 g l(-1)) and initial cell loading on enzyme production were studied. The production of tannase increased significantly with increasing alginate concentration and reached a maximum enzyme yield of 0.56 +/- 0.03 U ml(-1) at 20 g l(-1). This was about 1.70-fold higher than that obtained by free cells. The immobilized cells produced tannase consistently over 13 repeated cycles and reached a maximum level at the third cycle. Scanning electron microscope study indicated that the cells in Ca-alginate beads remain in normal shape. The Ca-alginate entrapment is a promising immobilization method of B. licheniformis KBR6 for repeated tannase production. Tannase production by immobilized cells is superior to that of free cells because it leads to higher volumetric activities within the same period of fermentation. This is the first report of tannase production from immobilized bacterial cells. The bacterium under study can produce higher amounts of tannase with respect to other fungal strains within a short cultivation period.

  16. Live cell imaging compatible immobilization of Chlamydomonas reinhardtii in microfluidic platform for biodiesel research.

    Science.gov (United States)

    Park, Jae Woo; Na, Sang Cheol; Nguyen, Thanh Qua; Paik, Sang-Min; Kang, Myeongwoo; Hong, Daewha; Choi, Insung S; Lee, Jae-Hyeok; Jeon, Noo Li

    2015-03-01

    This paper describes a novel surface immobilization method for live-cell imaging of Chlamydomonas reinhardtii for continuous monitoring of lipid droplet accumulation. Microfluidics allows high-throughput manipulation and analysis of single cells in precisely controlled microenvironment. Fluorescence imaging based quantitative measurement of lipid droplet accumulation in microalgae had been difficult due to their intrinsic motile behavior. We present a simple surface immobilization method using gelatin coating as the "biological glue." We take advantage of hydroxyproline (Hyp)-based non-covalent interaction between gelatin and the outer cell wall of microalgae to anchor the cells inside the microfluidic device. We have continuously monitored single microalgal cells for up to 6 days. The immobilized microalgae remain viable (viability was comparable to bulk suspension cultured controls). When exposed to wall shear stress, most of the cells remain attached up to 0.1 dyne/cm(2) . Surface immobilization allowed high-resolution, live-cell imaging of mitotic process in real time-which followed previously reported stages in mitosis of suspension cultured cells. Use of gelatin coated microfluidics devices can result in better methods for microalgae strain screening and culture condition optimization that will help microalgal biodiesel become more economically viable. © 2014 Wiley Periodicals, Inc.

  17. Bioreduction of chromate by immobilized cells of Halomonas sp

    Energy Technology Data Exchange (ETDEWEB)

    Murugavelh, S.; Mohanty, Kaustubha [Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati – 781039, Assam (India)

    2013-07-01

    In this work, the bioreduction of Cr(VI) by immobilized cells of Halomonas sp was reported. Ca alginate, acryl amide and agar were tested as the matrices for immobilization. Ca alginate was found to be the suitable matrix among the different matrices studied. Of the various dosages of inoculum studied 2 g/L was found to be the optimum. Glucose at 1 g L-1 was completely utilized by the immobilized Halomonas sp even in the presence of Cr(VI) at 40 mg L-1. The optimum pH for the bioreduction of Cr(VI) by immobilized Halomonas sp was found to be pH 6. The mechanical strength of the beads plays an essential role in the bioreduction process. Halomonas sp entrapped in a alginate matrix reported a maximum of 98.9 % of reduction for an initial Cr(VI) concentration of 10 mg L-1. The alginate beads can be reused for 3 times with slight drop in the percentage reduction. The presence of other metals decreased the bioreduction percentage.

  18. Production of R-Mandelic Acid Using Nitrilase from Recombinant E. coli Cells Immobilized with Tris(Hydroxymethyl)Phosphine.

    Science.gov (United States)

    Zhang, Xin-Hong; Liu, Zhi-Qiang; Xue, Ya-Ping; Wang, Yuan-Shan; Yang, Bo; Zheng, Yu-Guo

    2018-03-01

    Recombinant Escherichia coli cells harboring nitrilase from Alcaligenes faecalis were immobilized using tris(hydroxymethyl)phosphine (THP) as the coupling agent. The optimal pH and temperature of the THP-immobilized cells were determined at pH 8.0 and 55 °C. The half-lives of THP-immobilized cells measured at 35, 40, and 50 °C were 1800, 965, and 163 h, respectively. The concentration of R-mandelic acid (R-MA) reached 358 mM after merely 1-h conversion by the immobilized cells with 500 mM R,S-mandelonitrile (R,S-MN), affording the highest productivity of 1307 g L -1  day -1 and the space-time productivity of 143.2 mmol L -1  h -1  g -1 . The immobilized cells with granular shape were successfully recycled for 60 batches using 100 mM R,S-MN as substrate at 40 °C with 64% of relative activity, suggesting that the immobilized E. coli cells obtained in this study are promising for the production of R-MA.

  19. Effect of Cell-to-matrix Ratio in Polyvinyl Alcohol Immobilized Pure and Mixed Cultures on Atrazine Degradation

    International Nuclear Information System (INIS)

    Siripattanakul, Sumana; Wirojanagud, Wanpen; McEvoy, John; Khan, Eakalak

    2008-01-01

    Atrazine biodegradation by immobilized pure and mixed cultures was examined. A pure atrazine-degrading culture, Agrobacterium radiobacter J14a (J14a), and a mixed culture (MC), isolated from an atrazine-contaminated crop field, were immobilized using phosphorylated-polyvinyl alcohol (PPVA). An existing cell immobilization procedure was modified to enhance PPVA matrix stability. The results showed that the matrices remained mechanically and chemically stable after shaking with glass beads over 15 days under various salt solutions and pH values. The immobilization process had a slight effect on cell viability. With the aid of scanning electron microscopy, a suitable microstructure of PPVA matrices for cell entrapment was observed. There were two porous layers of spherical gel matrices, the outside having an encapsulation property and the inside containing numerous pores for bacteria to occupy. J14a and MC were immobilized at three cell-to-matrix ratios of 3.5, 6.7, and 20 mg dry cells/mL matrix. The atrazine biodegradation tests were conducted in an aerobic batch system, which was inoculated with cells at 2,000 mg/L. The tests were also conducted using free (non-immobilized) J14a and MC for comparative purpose. The cell-to-matrix ratio of 3.5 mg/mL provided the highest atrazine removal efficiency of 40-50% in 120 h for both J14a and MC. The free cell systems, for both cultures, presented much lower atrazine removal efficiencies compared to the immobilized cell systems at the same level of inoculation

  20. Kinetic analysis of dihydroxyacetone production from crude glycerol by immobilized cells of Gluconobacter oxydans MTCC 904.

    Science.gov (United States)

    Dikshit, Pritam Kumar; Moholkar, Vijayanand S

    2016-09-01

    The present study has investigated kinetic features of bioconversion of biodiesel-derived crude glycerol to dihydroxyacetone with immobilized Gluconobacter oxydans cells using modified Haldane substrate-inhibition model. The results have been compared against free cells and pure glycerol. Relative variations in the kinetic parameters KS, KI, Vmax, n and X reveal that immobilized G. oxydans cells (on PU foam substrate) with crude glycerol as substrate give higher order of inhibition (n) and lower maximum reaction velocities (Vmax). These results are essentially implications of substrate transport restrictions across immobilization matrix, which causes retention of substrate in the matrix and reduction in fractional available substrate (X) for the cells. This causes reduction in both KS (substrate concentration at Vmax/2) and KI (inhibition constant) as compared to free cells. For immobilized cells, substrate concentration (Smax) corresponding to Vmax is practically same for both pure and crude glycerol as substrate. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Production of D-alanine from DL-alanine using immobilized cells of Bacillus subtilis HLZ-68.

    Science.gov (United States)

    Zhang, Yangyang; Li, Xiangping; Zhang, Caifei; Yu, Xiaodong; Huang, Fei; Huang, Shihai; Li, Lianwei; Liu, Shiyu

    2017-09-13

    Immobilized cells of Bacillus subtilis HLZ-68 were used to produce D-alanine from DL-alanine by asymmetric degradation. Different compounds such as polyvinyl alcohol and calcium alginate were employed for immobilizing the B. subtilis HLZ-68 cells, and the results showed that cells immobilized using a mixture of these two compounds presented higher L-alanine degradation activity, when compared with free cells. Subsequently, the effects of different concentrations of polyvinyl alcohol and calcium alginate on L-alanine consumption were examined. Maximum L-alanine degradation was exhibited by cells immobilized with 8% (w/v) polyvinyl alcohol and 2% (w/v) calcium alginate. Addition of 400 g of DL-alanine (200 g at the beginning of the reaction and 200 g after 30 h of incubation) into the reaction solution at 30 °C, pH 6.0, aeration of 1.0 vvm, and agitation of 400 rpm resulted in complete L-alanine degradation within 60 h, leaving 185 g of D-alanine in the reaction solution. The immobilized cells were applied for more than 15 cycles of degradation and a maximum utilization rate was achieved at the third cycle. D-alanine was easily extracted from the reaction solution using cation-exchange resin, and the chemical and optical purity of the extracted D-alanine was 99.1 and 99.6%, respectively.

  2. Magnetically modified bacterial cellulose: A promising carrier for immobilization of affinity ligands, enzymes, and cells

    Energy Technology Data Exchange (ETDEWEB)

    Baldikova, Eva [Global Change Research Institute, CAS, Na Sadkach 7, 370 05 Ceske Budejovice (Czech Republic); Pospiskova, Kristyna [Regional Centre of Advanced Technologies and Materials, Palacky University, Slechtitelu 27, 783 71 Olomouc (Czech Republic); Ladakis, Dimitrios; Kookos, Ioannis K. [Department of Chemical Engineering, University of Patras, 26504 Patras, Rio (Greece); Koutinas, Apostolis A. [Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, Athens 11855 (Greece); Safarikova, Mirka [Global Change Research Institute, CAS, Na Sadkach 7, 370 05 Ceske Budejovice (Czech Republic); Department of Nanobiotechnology, Biology Centre, ISB, CAS, Na Sadkach 7, 370 05 Ceske Budejovice (Czech Republic); Safarik, Ivo, E-mail: safarik@nh.cas.cz [Global Change Research Institute, CAS, Na Sadkach 7, 370 05 Ceske Budejovice (Czech Republic); Regional Centre of Advanced Technologies and Materials, Palacky University, Slechtitelu 27, 783 71 Olomouc (Czech Republic); Department of Nanobiotechnology, Biology Centre, ISB, CAS, Na Sadkach 7, 370 05 Ceske Budejovice (Czech Republic)

    2017-02-01

    Bacterial cellulose (BC) produced by Komagataeibacter sucrofermentans was magnetically modified using perchloric acid stabilized magnetic fluid. Magnetic bacterial cellulose (MBC) was used as a carrier for the immobilization of affinity ligands, enzymes and cells. MBC with immobilized reactive copper phthalocyanine dye was an efficient adsorbent for crystal violet removal; the maximum adsorption capacity was 388 mg/g. Kinetic and thermodynamic parameters were also determined. Model biocatalysts, namely bovine pancreas trypsin and Saccharomyces cerevisiae cells were immobilized on MBC using several strategies including adsorption with subsequent cross-linking with glutaraldehyde and covalent binding on previously activated MBC using sodium periodate or 1,4-butanediol diglycidyl ether. Immobilized yeast cells retained approximately 90% of their initial activity after 6 repeated cycles of sucrose solution hydrolysis. Trypsin covalently bound after MBC periodate activation was very stable during operational stability testing; it could be repeatedly used for ten cycles of low molecular weight substrate hydrolysis without loss of its initial activity. - Highlights: • Bacterial cellulose was magnetically modified with magnetic fluid. • Magnetic cellulose is an efficient carrier for affinity ligands. • Enzymes and cells can be efficiently immobilized to magnetic cellulose.

  3. Hydrophilic PCU scaffolds prepared by grafting PEGMA and immobilizing gelatin to enhance cell adhesion and proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Changcan; Yuan, Wenjie; Khan, Musammir; Li, Qian [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Feng, Yakai, E-mail: yakaifeng@tju.edu.cn [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Key Laboratory of Systems Bioengineering of Ministry of Education, Tianjin University, Tianjin 300072 (China); Tianjin University-Helmholtz-Zentrum Geesthacht, Joint Laboratory for Biomaterials and Regenerative Medicine, Tianjin 300072 (China); Collaborative Innovation Center of Chemical Science and Chemical Engineering (Tianjin) Tianjin 300072 (China); Yao, Fanglian [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Key Laboratory of Systems Bioengineering of Ministry of Education, Tianjin University, Tianjin 300072 (China); Tianjin University-Helmholtz-Zentrum Geesthacht, Joint Laboratory for Biomaterials and Regenerative Medicine, Tianjin 300072 (China); Zhang, Wencheng, E-mail: wenchengzhang@yahoo.com [Department of Physiology and Pathophysiology, Logistics University of Chinese People' s Armed Police Force, Tianjin 300162 (China)

    2015-05-01

    Gelatin contains many functional motifs which can modulate cell specific adhesion, so we modified polycarbonate urethane (PCU) scaffold surface by immobilization of gelatin. PCU-g-gelatin scaffolds were prepared by direct immobilizing gelatins onto the surface of aminated PCU scaffolds. To increase the immobilization amount of gelatin, poly(ethylene glycol) methacrylate (PEGMA) was grafted onto PCU scaffolds by surface initiated atom transfer radical polymerization. Then, following amination and immobilization, PCU-g-PEGMA-g-gelatin scaffolds were obtained. Both modified scaffolds were characterized by chemical and biological methods. After immobilization of gelatin, the microfiber surface became rough, but the original morphology of scaffolds was maintained successfully. PCU-g-PEGMA-g-gelatin scaffolds were more hydrophilic than PCU-g-gelatin scaffolds. Because hydrophilic PEGMA and gelatin were grafted and immobilized onto the surface, the PCU-g-PEGMA-g-gelatin scaffolds showed low platelet adhesion, perfect anti-hemolytic activity and excellent cell growth and proliferation capacity. It could be envisioned that PCU-g-PEGMA-g-gelatin scaffolds might have potential applications in tissue engineering artificial scaffolds. - Graphical abstract: PCU-g-gelatin scaffolds were prepared by direct immobilizing gelatin onto the surface of aminated PCU scaffolds (method a). To increase the immobilization amount of gelatin, PEGMAs were grafted onto the scaffold surface by SI-ATRP. PCU-g-PEGMA-g-gelatin scaffolds were prepared by method b. The gelatin modified scaffolds exhibited high hydrophilicity, low platelet adhesion, perfect anti-hemolytic activity, and excellent cell adhesion and proliferation capacity. They might have potential applications as tissue engineering scaffolds for artificial blood vessels. - Highlights: • Hydrophilic scaffolds were prepared by grafting PEGMA and immobilization of gelatins. • Grafting PEGMA enhanced the immobilization amount of gelatin

  4. Cell adsorption and selective desorption for separation of microbial cells by using chitosan-immobilized silica.

    Science.gov (United States)

    Kubota, Munehiro; Matsui, Masayoshi; Chiku, Hiroyuki; Kasashima, Nobuyuki; Shimojoh, Manabu; Sakaguchi, Kengo

    2005-12-01

    Cell adsorption and selective desorption for separation of microbial cells were conducted by using chitosan-immobilized silica (CIS). When chitosan was immobilized onto silica surfaces with glutaraldehyde, bacterial cells adsorbed well and retained viability. Testing of the adsorption and desorption ability of CIS using various microbes such as Escherichia coli, Aeromonas hydrophila, Pseudomonas aeruginosa, Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus, Staphylococcus epidermidis, Lactobacillus casei, Streptococcus mutans, Streptococcus sobrinus, Streptococcus salivarius, Saccharomyces cerevisiae, Saccharomyces ludwigii, and Schizosaccharomyces pombe revealed that most microbes could be adsorbed and selectively desorbed under different conditions. In particular, recovery was improved when L-cysteine was added. A mixture of two bacterial strains adsorbed onto CIS could also be successfully separated by use of specific solutions for each strain. Most of the desorbed cells were alive. Thus, quantitative and selective fractionation of cells is readily achievable by employing chitosan, a known antibacterial material.

  5. [Comparison of fibroblastic cell compatibility of type I collagen-immobilized titanium between electrodeposition and immersion].

    Science.gov (United States)

    Kyuragi, Takeru

    2014-03-01

    Titanium is widely used for medical implants. While many techniques for surface modification have been studied for optimizing its biocompatibility with hard tissues, little work has been undertaken to explore ways of maximizing its biocompatibility with soft tissues. We investigated cell attachment to titanium surfaces modified with bovine Type I collagen immobilized by either electrodeposition or a conventional immersion technique. The apparent thickness and durability of the immobilized collagen layer were evaluated prior to incubation of the collagen-immobilized titanium surfaces with NIH/3T3 mouse embryonic fibroblasts. The initial cell attachment and expression of actin and vinculin were evaluated. We determined that the immobilized collagen layer was much thicker and more durable when placed using the electrodeposition technique than the immersion technique. Both protocols produced materials that promoted better cell attachment, growth and structural protein expression than titanium alone. However, electrodeposition was ultimately superior to immersion because it is quicker to perform and produces a more durable collagen coating. We conclude that electrodeposition is an effective technique for immobilizing type I collagen on titanium surfaces, thus improving their cytocompatibility with fibroblasts.

  6. Plasma modified PLA electrospun membranes for actinorhodin production intensification in Streptomyces coelicolor immobilized-cell cultivations.

    Science.gov (United States)

    Scaffaro, Roberto; Lopresti, Francesco; Sutera, Alberto; Botta, Luigi; Fontana, Rosa Maria; Gallo, Giuseppe

    2017-09-01

    Most of industrially relevant bioproducts are produced by submerged cultivations of actinomycetes. The immobilization of these Gram-positive filamentous bacteria on suitable porous supports may prevent mycelial cell-cell aggregation and pellet formation which usually negatively affect actinomycete submerged cultivations, thus, resulting in an improved biosynthetic capability. In this work, electrospun polylactic acid (PLA) membranes, subjected or not to O 2 -plasma treatment (PLA-plasma), were used as support for immobilized-cell submerged cultivations of Streptomyces coelicolor M145. This strain produces different bioactive compounds, including the blue-pigmented actinorhodin (ACT) and red-pigmented undecylprodigiosin (RED), and constitutes a model for the study of antibiotic-producing actinomycetes. Wet contact angles and X-ray photoelectron spectroscopy analysis confirmed the increased wettability of PLA-plasma due to the formation of polar functional groups such as carboxyl and hydroxyl moieties. Scanning electron microscope observations, carried out at different incubation times, revealed that S. coelicolor immobilized-cells created a dense "biofilm-like" mycelial network on both kinds of PLA membranes. Cultures of S. coelicolor immobilized-cells on PLA or PLA-plasma membranes produced higher biomass (between 1.5 and 2 fold) as well as higher levels of RED and ACT than planktonic cultures. In particular, cultures of immobilized-cells on PLA and PLA-plasma produced comparable levels of RED that were approximatively 4 and 5 fold higher than those produced by planktonic cultures, respectively. In contrast, levels of ACT produced by immobilized-cell cultures on PLA and PLA-plasma were different, being 5 and 10 fold higher than those of planktonic cultures, respectively. Therefore, this is study demonstrated the positive influence of PLA membrane on growth and secondary metabolite production in S. coelicolor and also revealed that O 2 -plasma treated PLA membranes

  7. Physicochemical characterization of the yeast cells and the waste lignocellulosic particles in the immobilization process for ethanol production

    DEFF Research Database (Denmark)

    Agudelo-Escobar, Lina María; Mussatto, Solange I.; Peñuela, Mariana

    2017-01-01

    Ethanol is one of the leading alternative fuels. Efforts have increased the development of technologies for producing ethanol efficiently and economically. The continuous fermentation using yeast cells immobilized in low‐cost materials is presented as an excellent alternative. We used four...... to confirm the hydrophobic or hydrophilic character and the free energies interaction was established. Images were obtained by scanning electron microscope, and determination of surface areas and volumes was performed by adsorption and desorption isotherms. It was established that cell surface properties...... are modified by the immobilization process to which they are subjected. It was evident that cell immobilization depended on the properties of the carrier, as well as cell surface properties. Thus, in order to improve the process of cell immobilization, it is essential to understand the type of carrier‐cell...

  8. Immobilization of anaerobic thermophilic bacteria for the production of cell-free thermostable. alpha. -amylases and pullulanases

    Energy Technology Data Exchange (ETDEWEB)

    Klingeberg, M [Goettingen Univ. (Germany, F.R.). Inst. fuer Mikrobiologie; Vorlop, K D [Technische Univ. Braunschweig (Germany, F.R.). Inst. fuer Technische Chemie; Antranikian, G [Technische Univ. Hamburg-Harburg, Hamburg (Germany, F. R.). Arbeitsbereich Biotechnologie 1

    1990-08-01

    For the production of cell-free thermostable {alpha}-amylases and pullulanases various anaerobic thermophilic bacteria that belong to the genera Clostridium and Thermoanaerobacter were immobilized in calcium alginate gel beads. The entrapment of bacteria was performed in full was well as in hollow spheres. An optimal limited medium, which avoided bacterial outgrowth, was developed for the cultivation of immobilized organisms at 60deg C using 0.4% starch as substrate. Compared to non-immobilized cells these techniques allowed a significant increase (up to 5.6-fold) in the specific activities of the extracellular enzymes formed. An increase in the productivity of extracellular enzymes was observed after immobilization of bacteria in full spheres. In the case of C. thermosaccharolyticum, for instance, the productivity was raised from 90 units (U)/10{sup 12} cells up to 700 U/10{sup 12} cells. Electrophoretic analysis of the secreted proteins showed that in all cases most of the amylolytic enzymes formed were released into the culture medium. Proteins that had a molecular mass of less than 450 000 daltons could easily diffuse through the gel matrix. Cultivation of immobilized bacteria in semi-continuous and fed-batch cultures was also accompanied by an elevation in the concentration of cell-free enzymes. (orig.).

  9. Electrophoresis of cell membrane heparan sulfate regulates galvanotaxis in glial cells.

    Science.gov (United States)

    Huang, Yu-Ja; Schiapparelli, Paula; Kozielski, Kristen; Green, Jordan; Lavell, Emily; Guerrero-Cazares, Hugo; Quinones-Hinojosa, Alfredo; Searson, Peter

    2017-08-01

    Endogenous electric fields modulate many physiological processes by promoting directional migration, a process known as galvanotaxis. Despite the importance of galvanotaxis in development and disease, the mechanism by which cells sense and migrate directionally in an electric field remains unknown. Here, we show that electrophoresis of cell surface heparan sulfate (HS) critically regulates this process. HS was found to be localized at the anode-facing side in fetal neural progenitor cells (fNPCs), fNPC-derived astrocytes and brain tumor-initiating cells (BTICs), regardless of their direction of galvanotaxis. Enzymatic removal of HS and other sulfated glycosaminoglycans significantly abolished or reversed the cathodic response seen in fNPCs and BTICs. Furthermore, Slit2, a chemorepulsive ligand, was identified to be colocalized with HS in forming a ligand gradient across cellular membranes. Using both imaging and genetic modification, we propose a novel mechanism for galvanotaxis in which electrophoretic localization of HS establishes cell polarity by functioning as a co-receptor and provides repulsive guidance through Slit-Robo signaling. © 2017. Published by The Company of Biologists Ltd.

  10. A CORN STEM AS BIOMATERIAL FOR SACCHAROMYCES CEREVISIAE CELLS IMMOBILIZATION FOR THE ETHANOL PRODUCTION

    Directory of Open Access Journals (Sweden)

    Vesna Vučurović

    2008-11-01

    Full Text Available This study provides a preliminary contribution to the development of a bioprocess for the production of ethanol using Saccharomyces cerevisiae cells immobilized onto a corn stem. For this purpose, the yeast cells were submitted to the batch tests in situ adsorption onto 0.5 cm long corn stem. Cells immobilization was analyzed by optical microscopy. The number of the yeast cells, fermentation kinetics, the ethanol yield in the presence or the absence of the support in the fermentation medium was investigated. It was determined that the addition of the corn stem led to the abrupt increase of the yeast cells number in substrate, ethanol yield, pH value, a total dissolved salts content and substrate conductivity. The addition of 5 and 10g of the corn stem pith per liter of the medium decreased the amount of residual sugar. The results indicate that a corn stem might be a good carrier for the yeast cell immobilization, and also a cheap alternative recourse of mineral components with the possibility of application for improving ethanol productivities.

  11. Production of α-keto acids Part I. Immobilized cells ofTrigonopsis variabilis containing D-amino acid oxidase.

    Science.gov (United States)

    Brodelius, P; Nilsson, K; Mosbach, K

    1981-12-01

    Whole cells ofTrigonopsis variabilis were immobilized by entrapment in Ca(2+)-alginate and used for the production of α-keto acids from the corresponding D-amino acids. The D-amino acid oxidase within the immobilized cells has a broad substrate specificity. Hydrogen peroxide formed in the enzymatic reaction was efficiently hydrolyzed by manganese oxide co-immobilized with the cells. The amino acid oxidase activity was assayed with a new method based on reversed-phase HPLC. Oxygen requirements, bead size, concentration of cells in the beads, flow rate, and other factors were investigated in a " trickle-bed " reactor.

  12. Radiosensitivity evaluation of Human tumor cell lines by single cell gel electrophoresis

    International Nuclear Information System (INIS)

    Zhang Yipei; Cao Jia; Wang Yan; Du Liqing; Li Jin; Wang Qin; Fan Feiyue; Liu Qiang

    2011-01-01

    Objective: To explore the feasibility of determining radiosensitivity of human tumor cell lines in vitro using single cell gel electrophoresis (SCGE). Methods: Three human tumor cell lines were selected in this study, HepG 2 , EC-9706 and MCF-7. The surviving fraction (SF) and DNA damage were detected by MTT assay, nested PCR technique and comet assay respectively. Results: MTT assay: The SF of HepG 2 and EC-9706 after irradiated by 2, 4 and 8 Gy was lower significantly than that of MCF-7, which showed that the radiosensitivity of HepG 2 and EC-9706 was higher than that of MCF-7. But there was no statistical difference of SF between HepG 2 and EC-9706. SCGE: The difference of radiosensitivity among these three tumor cell lines was significant after 8 Gy γ-ray irradiation. Conclusion: The multi-utilization of many biological parameter is hopeful to evaluate the radiosensitivity of tumor cells more objectively and exactly. (authors)

  13. The study of preparation for immobilized cells membranes of E. Coli. by radiation technique

    International Nuclear Information System (INIS)

    Cao Jin; Chen Pin; Yu Yi

    1991-01-01

    The paper described the preparation of immobilized cells membranes with E. Coli by radiation technique. The nylon 6 was grafted with HEMA, which as a matrix to prepare immobilized cells membranes with E. Coli. by radiation entrapment at low temperature. The results showed that the retentive activity possessed a maximum value for membranes with E. Coli. when the irradiation dose was at 10-12 kGy, the entrapped cells has 2.3 g/ml at 50% HEMA concentration, the optimum pH and optimum temperature for membranes with E. Coli. are as same the original cells

  14. State and Kinetic Parameters Estimation of Bio-Ethanol Production with Immobilized Cells

    OpenAIRE

    Mihaylova, Iva; Popova, Silviya; Kostov, Georgi; Ignatova, Maya; Lubenova, Velislava; Naydenova, Vessela; Pircheva, Desislava; Angelov, Mihail

    2013-01-01

    In this paper, state and kinetic parameters estimation based on extended Kalman filter (EKF) is proposed. Experimental data from alcoholic fermentation process with immobilized cells is used. The measurements of glucose and ethanol concentration are used as on-line measurements for observers design and biomass concentration is used for results verification. Biomass, substrate and product concentrations inside immobilized compounds are estimated using the proposed algorithm. Monitoring of the ...

  15. Ethanol production from molasses by immobilized cells of zymomonas mobilis EMCC 1546

    International Nuclear Information System (INIS)

    Meliegy, S.A.; Abdelaziz, A.H.

    2004-01-01

    Ethanol production from beet molasses by zymomonas mobilis EMCC 1546 was studied using continuous processes in which immobilized bacterial cells of Z.mobilis EMCC 1546 was grown on both sodium alginate and polyvinyl alcohol(PVA). The fermentation was performed in a shaking incubation and 1-liter ferment or with final working 750 ml. The initial sugar concentration studied was 50, 100,150, 200 and 250 g/l. The results showed that optimum initial sugar for ethanol production was 200 g/l. In batch fermentation, the highest ethanol concentration was 28.50 g/. Also effect of gamma irradiation was studied to enhance ethanol production. The highest ethanol production at dose dose 0.25 kGy was 34.82 g/l. The results showed that continuous fermentation, at dilution rate 1.36 (I/h), helped to increase the ethanol production significantly and continuous fermentation with immobilized cells in alginate gave higher ethanol production, 35.8 (g/I), as compared with those immobilized in hydrogel (PVA)

  16. Nonradioactive telomerase activity assay by microchip electrophoresis: privileges to the classical gel electrophoresis assay.

    Science.gov (United States)

    Zhelev, Zhivko; Bakalova, Rumiana; Ewis, Ashraf; Ohba, Hideki; Ishikawa, Mitsuru; Baba, Yoshinobu

    2005-08-01

    The present study accents on the privileges of microchip-based electrophoresis to the conventional gel electrophoresis in separation of telomerase repeat amplification protocol/polymerase chain reaction (PCR) ladder products obtained in telomerase-catalyzed reaction in cancer cells. We try to clarify the interpretation of the results obtained by both electrophoretic procedures and to avoid misinterpretation as a result of PCR-dependent artefacts.

  17. Continuous ethanol production using immobilized yeast cells entrapped in loofa-reinforced alginate carriers

    Directory of Open Access Journals (Sweden)

    Phoowit Bangrak

    2011-06-01

    Full Text Available A culture of Saccharomyces cerevisiae M30 entrapped in loofa-reinforced alginate was used for continuous ethanol fermentation in a packed-bed reactor with initial sugar concentrations of 200-248 g/L. Maximum ethanol productivity of 11.5 g/(L·h was obtained at an ethanol concentration of 57.4 g/L, an initial sugar concentration of 220 g/L and a dilution rate (D of 0.2 h-1. However, a maximum ethanol concentration of 82.1 g/L (productivity of 9.0 g/(L·h was obtained at a D of 0.11 h-1. Ethanol productivity in the continuous culture was 6-8-fold higher than that in the batch culture. Due to the developed carrier's high biocompatibility, high porosity, and good mechanical strength, advantages such as cell regeneration, reusability, altered mechanical strength, and high capacity to trap active cells in the reactor were achieved in this study. The immobilized cell reactor was successfully operated for 30 days without any loss in ethanol productivity. The average conversion yield was 0.43-0.45 throughout the entire operation, with an immobilization yield of 47.5%. The final total cell concentration in the reactor was 37.3 g/L (17.7 g/L immobilized cells and 19.6 g/L suspended cells. The concentration of suspended cells in the effluent was 0.8 g/L.

  18. Biosorption of uranium by immobilized cells of Rhodotorula glutinis

    International Nuclear Information System (INIS)

    Jing Bai; Zhan Li; Fangli Fan; Xiaolei Wu; Xiaojie Yin; Longlong Tian; Zhi Qin; Junsheng Guo

    2014-01-01

    Biosorption of uranium ions from diluted solution (≤40 mg L -1 ) onto immobilized cells of Rhodotorula glutinis was investigated in a batch system. Equilibrium, kinetic and thermodynamic studies were conducted by considering the effect of initial uranium concentration, contact time and temperature. Non-linear forms of Langmuir, Freundlich and Sips isotherm models were used to fit the equilibrium data, Sips model was designated as the best one. Kinetic data were simulated by non-linear pseudo-first-order, pseudo-second-order and intra-particle diffusion equations. Pseudo-first-order kinetic equation described the experimental data better than pseudo-second-order equation and intra-particle diffusion equation can fit the kinetic data with two independent curves. Thermodynamic parameters, including ∆H 0, ∆G 0 and ∆S 0, were evaluated, the sorption process was determined to be spontaneous and endothermic. Uranium sorption from pure uranium solutions and uranium pit wastewater by immobilized biomass and blank beads, as well as the regeneration results indicated that immobilized R. glutinis can be use to recovery uranium from uranium pit wastewater. (author)

  19. Repeated batch production of ethanol from Jerusalem artichoke tubers using recycled immobilized cells of Kluyveromyces fragilis

    Energy Technology Data Exchange (ETDEWEB)

    Margaritis, A.; Bajpai, P.

    1981-01-01

    Recycled immobilized cells of K. fragilis ATCC 28244 were used for repeated batch production of EtOH from the inulin sugars derived from Jerusalem artichoke tubers. Using 10% initial sugar concentration, a maximum EtOH concentration of 48 g/l was achieved in 7 h when the immobilized cell concentration in the Ca alginate beads was 72 g dry weight immobilized cell/l bioreactor vol.-h. The same Ca alginate beads containing the cells were used repeatedly for 11 batch runs starting with fresh medium at the beginning of each run. The EtOH yield was almost constant at 96% of the theoretical for all 11 batch runs, while the maximum EtOH production rate during the last batch run was 70% of the original EtOH rate obtained in the 1st batch run.

  20. The enhancement of chondrogenesis of ATDC5 cells in RGD-immobilized microcavitary alginate hydrogels.

    Science.gov (United States)

    Yao, Yongchang; Zeng, Lei; Huang, Yuyang

    2016-07-01

    In our previous work, we have developed an effective microcavitary alginate hydrogel for proliferation of chondrocytes and maintenance of chondrocytic phenotype. In present work, we investigated whether microcavitary alginate hydrogel could promote the chondrogenesis of progenitor cells. Moreover, we attempted to further optimize this system by incorporating synthetic Arg-Gly-Asp peptide. ATDC5 cells were seeded into microcavitary alginate hydrogel with or without Arg-Gly-Asp immobilization. Cell Counting Kit-8 and live/dead staining were conducted to analyze cell proliferation. Real-time polymerase chain reaction (RT-PCR), hematoxylin and eosin, and Toluidine blue O staining as well as Western blot assay was performed to evaluate the cartilaginous markers at transcriptional level and at protein level, respectively. The obtained data demonstrated that Arg-Gly-Asp-immobilized microcavitary alginate hydrogel was preferable to promote the cell proliferation. Also, Arg-Gly-Asp-immobilized microcavitary alginate hydrogel improved the expression of chondrocytic genes including Collagen II and Aggrecan when compared with microcavitary alginate hydrogel. The results suggested that microcavitary alginate hydrogel could promote the chondrogenesis. And Arg-Gly-Asp would be promising to ameliorate this culture system for cartilage tissue engineering. © The Author(s) 2016.

  1. Enhanced production of alkaline thermostable keratinolytic protease from calcium alginate immobilized cells of thermoalkalophilic Bacillus halodurans JB 99 exhibiting dehairing activity.

    Science.gov (United States)

    Shrinivas, Dengeti; Kumar, Raghwendra; Naik, G R

    2012-01-01

    The thermoalkalophilic Bacillus halodurans JB 99 cells known for production of novel thermostable alkaline keratinolytic protease were immobilized in calcium alginate matrix. Batch and repeated batch cultivation using calcium alginate immobilized cells were studied for alkaline protease production in submerged fermentation. Immobilized cells with 2.5% alginate and 350 beads/flask of initial cell loading showed enhanced production of alkaline protease by 23.2% (5,275 ± 39.4 U/ml) as compared to free cells (4,280 ± 35.4 U/ml) after 24 h. In the semicontinuous mode of cultivation, immobilized cells under optimized conditions produced an appreciable level of alkaline protease in up to nine cycles and reached a maximal value of 5,975 U/ml after the seventh cycle. The enzyme produced from immobilized cells efficiently degraded chicken feathers in the presence of a reducing agent which can help the poultry industry in the management of keratin-rich waste and obtaining value-added products.

  2. Analysis of the surface membrane of iodinated leukemic cells by SDS-polyacrylamide gel electrophoresis

    International Nuclear Information System (INIS)

    Ishitani, Kunihiko; Ikeda, Akira; Tamura, Minoru; Takeuchi, Hidekazu; Ihara, Koji

    1980-01-01

    Surface proteins of human leukemic cells were labeled selectively by lactoperoxydase catalysed-iodination and examined by SDS-polyacrylamide gel electrophoresis. The electrophoretic pattern of the surface membranes of cells from a patients with chronic mylogeneous leukemia in blast crisis was of B cell type and showed Ia like antigen. Leukemic cells from a patient with hairly cell leukemia also expressed the pattern of B cell type when tested by this method the technique of iodinating cell surface with lactoperoxidase is useful in characterization of leukemia cells for diagnosis and monitoring of clinical course. (author)

  3. Effects of immobilization on spermiogenesis

    Science.gov (United States)

    Meitner, E. R.

    1980-01-01

    The influence of immobilization stress on spermiogenesis in rats was investigated. After 96 hour immobilization, histological changes began to manifest themselves in the form of practically complete disappearance of cell population of the wall of seminiferous tubule as well as a markedly increased number of cells with pathologic mitoses. Enzymological investigations showed various changes of activity (of acid and alkaline phosphatase and nonspecific esterase) in the 24, 48, and 96 hour immobilization groups.

  4. Ethanol production by repeated batch and continuous fermentations of blackstrap molasses using immobilized yeast cells on thin-shell silk cocoons

    International Nuclear Information System (INIS)

    Rattanapan, Anuchit; Limtong, Savitree; Phisalaphong, Muenduen

    2011-01-01

    Highlights: → Thin-shell silk cocoons for immobilization of Saccharomycescerevisiae. → Advantages: high mechanical strength, light weight, biocompatibility and high surface area. → Enhanced cell stability and ethanol productivity by the immobilization system. -- Abstract: A thin-shell silk cocoon (TSC), a residual from the silk industry, is used as a support material for the immobilization of Saccharomyces cerevisiae M30 in ethanol fermentation because of its properties such as high mechanical strength, light weight, biocompatibility and high surface area. In batch fermentation with blackstrap molasses as the main fermentation substrate, an optimal ethanol concentration of 98.6 g/L was obtained using a TSC-immobilized cell system at an initial reducing sugar concentration of 240 g/L. The ethanol concentration produced by the immobilized cells was 11.5% higher than that produced by the free cells. Ethanol production in five-cycle repeated batch fermentation demonstrated the enhanced stability of the immobilized yeast cells. Under continuous fermentation in a packed-bed reactor, a maximum ethanol productivity of 19.0 g/(L h) with an ethanol concentration of 52.8 g/L was observed at a 0.36 h -1 dilution rate.

  5. Production of organic acids in an immobilized cell reactor using ...

    African Journals Online (AJOL)

    Immobilized cell reactor (ICR) was developed as a novel bioreactor to convert hydrolyzed sugars to organic acids. Sugar fermentation by Propionibacterium acid-propionici entraped by calcium alginate was carried out in continuous mode to produce propionic and acetic acids. In continuous fermentation, more than 90 ...

  6. Internalization: acute apoptosis of breast cancer cells using herceptin-immobilized gold nanoparticles

    Directory of Open Access Journals (Sweden)

    Rathinaraj P

    2015-02-01

    Full Text Available Pierson Rathinaraj,1 Ahmed M Al-Jumaily,1 Do Sung Huh21Institute of Biomedical Technologies, Auckland University of Technology, Auckland, New Zealand; 2Department of Nano science and Engineering, Inje University, Gimhea, South KoreaAbstract: Herceptin, the monoclonal antibody, was successfully immobilized on gold nanoparticles (GNPs to improve their precise interactions with breast cancer cells (SK-BR3. The mean size of the GNPs (29 nm, as determined by dynamic light scattering, enlarged to 82 nm after herceptin immobilization. The in vitro cell culture experiment indicated that human skin cells (FB proliferated well in the presence of herceptin-conjugated GNP (GNP–Her, while most of the breast cancer cells (SK-BR3 had died. To elucidate the mechanism of cell death, the interaction of breast cancer cells with GNP–Her was tracked by confocal laser scanning microscopy. Consequently, GNP–Her was found to be bound precisely to the membrane of the breast cancer cell, which became almost saturated after 6 hours incubation. This shows that the progression signal of SK-BR3 cells is retarded completely by the precise binding of antibody to the human epidermal growth factor receptor 2 receptor of the breast cancer cell membrane, causing cell death.Keywords: herceptin, gold nanoparticles, SK-BR3 cells, intracellular uptake

  7. Growth and substrate consumption of Nitrobacter agilis cells immobilized in carrageenan: part 1. Dynamic modeling.

    Science.gov (United States)

    de Gooijer, C D; Wijffels, R H; Tramper, J

    1991-07-01

    The modeling of the growth of Nitrobacter agilis cell immobilized in kappa-carrageenan is presented. A detailed description is given of the modeling of internal diffusion and growth of cells in the support matrix in addition to external mass transfer resistance. The model predicts the substrate and biomass profiles in the support as well as the macroscopic oxygen consumption rate of the immobilized biocatalyst in time. The model is tested by experiments with continuously operated airlift loop reactors containing cells immobilized in kappa-carrageenan. The model describes experimental data very well. It is clearly shown that external mass transfer may not be neglected. Furthermore, a sensitivity analysis of the parameters at their values during the experiments revealed that apart from the radius of the spheres and the substrate bulk concentration, the external mass transfer resistance coefficient is the most sensitive parameter for our case.

  8. Electrophoresis in space at zero gravity

    Science.gov (United States)

    Bier, M.; Snyder, R. S.

    1974-01-01

    Early planning for manufacturing operations in space include the use of electrophoresis for purification and separation of biological materials. Greatly simplified electrophoresis apparatus have been flown in the Apollo 14 and 16 missions to test the possibility of stable liquid systems in orbit. Additionally, isoelectric focusing and isotachophoresis are of particular interest as they offer very high resolution and have self-sharpening boundaries. The value of possible space electrophoresis is substantial. For example, present technology permits large fractionation of only a few of blood proteins many fractions, and separated cell populations are needed for research.

  9. Glucoamylase biosynthesis by cells of Aspergillus niger C sub 58-III immobilized in sintered glass and pumice stones

    Energy Technology Data Exchange (ETDEWEB)

    Fiedurek, J.; Lobarzewski, J. (Uniwersytet Marii Curie-Sklodowskiej, Lublin (Poland). Inst. Mikrobiologii i Biochemii)

    1990-09-01

    A simple method of A. niger C{sub 58-III} cell immobilization is described. This strain produces extracellular glucoamylase. According to the proposed method A. niger spores were first immobilized by adsorption in sintered glass Rasching rings (RR) or pumice stones (PS). Growing out from spores, A. niger cells produced extracellular glucoamylase. This technique facilitates the culture growth in a filamentous spongy structure of the supports with a continuous accumulation of biomass. After every 24 h it was possible to obtain culture liquid rich in glucoamylase. This procedure can be repeated 30 times using the same sample of immobilized A. niger culture without any loss of glucoamylase activity in the liquid medium. In a 96 h period immobilized A. niger cells produced 300 units . ml{sup -1} whereas a shake culture of this fungus produced only 186 units . ml{sup -1}. (orig.).

  10. Progress in biocatalysis with immobilized viable whole cells: systems development, reaction engineering and applications

    Czech Academy of Sciences Publication Activity Database

    Polakovič, M.; Švitel, J.; Bučko, M.; Filip, J.; Neděla, Vilém; Ansorge-Schumacher, M.B.; Gemeiner, P.

    2017-01-01

    Roč. 39, č. 5 (2017), s. 667-683 ISSN 0141-5492 Institutional support: RVO:68081731 Keywords : biocatalysis * immobilization methods * immobilized whole-cell biocatalyst * multienzyme cascade reactions * process economics * reaction engineering Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering OBOR OECD: Bioprocessing technologies (industrial processes relying on biological agents to drive the process) biocatalysis, fermentation Impact factor: 1.730, year: 2016

  11. Detection of telomerase activity using microchip electrophoresis.

    Science.gov (United States)

    Karasawa, Koji; Arakawa, Hidetoshi

    2015-07-01

    Telomerase participates in malignant transformation or immortalization of cells and thus has attracted attention as an anticancer drug target and diagnostic tumor marker. The telomeric repeat amplification protocol (TRAP) and improved TRAP methods (TRAP-fluorescence, TRAP-hybridization, etc.) are widely used forms of this telomerase assay. However, these approaches generally employ acrylamide gel electrophoresis after amplification of telomeric repeats by polymerase chain reaction (PCR), making these TRAP methods time consuming and technically demanding. In this study we developed a novel telomerase assay using microchip electrophoresis for rapid and highly sensitive detection of telomerase activity in cancer cells. The mixed gel of 0.8% hydroxypropyl methylcellulose (HPMC) and 0.3% polyethylene oxide (PEO) with SYBR Gold (fluorescent reagent) was used for microchip electrophoresis. As a result, the product amplified by a telomerase-positive cell could be measured in one cell per assay and detected with high reproducibility (CV=0.67%) in the short time of 100s. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Mapping of Chlamydia trachomatis proteins by immobiline-polyacrylamide two-dimensional electrophoresis: spot identification by N-terminal sequencing and immunoblotting

    DEFF Research Database (Denmark)

    Bini, L; Sanchez-Campillo, M; Santucci, A

    1996-01-01

    Proteins from purified elementary bodies of Chlamydia trachomatis were separated by two-dimensional gel electrophoresis on nonlinear wide-range immobilized pH gradients in the first dimension and polyacrylamide gradient gels in the second dimension. The maps obtained with this system are highly...

  13. Comparison between pulsed-field and constant-field gel electrophoresis for measurement of DNA double-strand breaks in irradiated Chinese hamster ovary cells

    International Nuclear Information System (INIS)

    Wlodek, D.; Banath, J.; Olive, P.L.

    1991-01-01

    Pulsed-field gel electrophoresis (PFGE) is one of the most sensitive methods for detecting DNA double-strand breaks in mammalian cells. However, it has been observed that constant-field gel electrophoresis (CFGE), when optimized, can detect breaks with equal efficiency. The migration of DNA from the well and the separation of DNA molecules according to size appear to be different processes; only the latter requires the application of PFGE. CFGE is very sensitive and can detect DNA damage produced by less than 5Gy of radiation. Low voltage (ca.0.6V/cm) during electrophoresis appears to be essential for the migration of the largest fraction of DNA from the agarose plug containing the cells; the electrophoresis run time, cell density in the plug, agarose concentration, nature of detergent and extent of radiolabelling are less important. It is concluded that CFGE is equally sensitive but more rapid and economical than PFGE for the measurement of DNA damage. (author)

  14. Diesel oil removal by immobilized Pseudoxanthomonas sp. RN402.

    Science.gov (United States)

    Nopcharoenkul, Wannarak; Netsakulnee, Parichat; Pinyakong, Onruthai

    2013-06-01

    Pseudoxanthomonas sp. RN402 was capable of degrading diesel, crude oil, n-tetradecane and n-hexadecane. The RN402 cells were immobilized on the surface of high-density polyethylene plastic pellets at a maximum cell density of 10(8) most probable number (MPN) g(-1) of plastic pellets. The immobilized cells not only showed a higher efficacy of diesel oil removal than free cells but could also degrade higher concentrations of diesel oil. The rate of diesel oil removal by immobilized RN402 cells in liquid culture was 1,050 mg l(-1) day(-1). Moreover, the immobilized cells could maintain high efficacy and viability throughout 70 cycles of bioremedial treatment of diesel-contaminated water. The stability of diesel oil degradation in the immobilized cells resulted from the ability of living RN402 cells to attach to material surfaces by biofilm formation, as was shown by CLSM imaging. These characteristics of the immobilized RN402 cells, including high degradative efficacy, stability and flotation, make them suitable for the purpose of continuous wastewater bioremediation.

  15. Investigation on accordance of DNA double-strand break of blood between in vivo and in vitro irradiation using single cell gel electrophoresis

    International Nuclear Information System (INIS)

    Liu Qiang; Jiang Enhai; Li Jin; Tang Weisheng; Wang Zhiquan; Zhao Yongcheng; Fan Feiyue

    2006-01-01

    Objective: To observe the consistency of DNA double-strand break between in vivo and in vitro irradiation, as a prophase study in radiation biodosimetry using single cell gel electrophoresis (SCGE). Methods: Detect DNA double-strand break after whole-body and in vitro radiation in mice lymphocytes using neutral single cell gel electrophoresis. The comet images were processed by CASP software and all the data were analysed by SPSS12.0. Results: There is no difference between in vivo and in vitro irradiation group in HDNA%, TDNA%, CL, TL, TM and OTM. Conclusion: The result of neutral single cell gel electrophoresis shortly after in vitro irradiation can precisely reflect the DNA double-strand break of lymphocytes in whole-body irradiation. (authors)

  16. Immobilizing live Escherichia coli for AFM studies of surface dynamics

    International Nuclear Information System (INIS)

    Lonergan, N.E.; Britt, L.D.; Sullivan, C.J.

    2014-01-01

    Atomic force microscopy (AFM) is a probe-based technique that permits high resolution imaging of live bacterial cells. However, stably immobilizing cells to withstand the probe-based lateral forces remains an obstacle in AFM mediated studies, especially those of live, rod shaped bacteria in nutrient media. Consequently, AFM has been under-utilized in the research of bacterial surface dynamics. The aim of the current study was to immobilize a less adherent Escherichia coli strain in a method that both facilitates AFM imaging in nutrient broth and preserves overall cell viability. Immobilization reagents and buffers were systematically evaluated and the cell membrane integrity was monitored in all sample preparations. As expected, the biocompatible gelatin coated surfaces facilitated stable cell attachment in lower ionic strength buffers, yet poorly immobilized cells in higher ionic strength buffers. In comparison, poly-L-lysine surfaces bound cells in both low and high ionic strength buffers. The benefit of the poly-L-lysine binding capacity was offset by the compromised membrane integrity exhibited by cells on poly-L-lysine surfaces. However, the addition of divalent cations and glucose to the immobilization buffer was found to mitigate this unfavorable effect. Ultimately, immobilization of E. coli cells on poly-L-lysine surfaces in a lower ionic strength buffer supplemented with Mg 2+ and Ca 2+ was determined to provide optimal cell attachment without compromising the overall cell viability. Cells immobilized in this method were stably imaged in media through multiple division cycles. Furthermore, permeability assays indicated that E. coli cells recover from the hypoosmotic stress caused by immobilization in low ionic strength buffers. Taken together, this data suggests that stable immobilization of viable cells on poly-L-lysine surfaces can be accomplished in lower ionic strength buffers that are supplemented with divalent cations for membrane stabilization while

  17. Ethanol production by fermentation using immobilized cells of Saccharomyces cerevisiae in cashew apple bagasse.

    Science.gov (United States)

    Pacheco, Alexandre Monteiro; Gondim, Diego Romão; Gonçalves, Luciana Rocha Barros

    2010-05-01

    In this work, cashew apple bagasse (CAB) was used for Saccharomyces cerevisiae immobilization. The support was prepared through a treatment with a solution of 3% HCl, and delignification with 2% NaOH was also conducted. Optical micrographs showed that high populations of yeast cells adhered to pre-treated CAB surface. Ten consecutive fermentations of cashew apple juice for ethanol production were carried out using immobilized yeasts. High ethanol productivity was observed from the third fermentation assay until the tenth fermentation. Ethanol concentrations (about 19.82-37.83 g L(-1) in average value) and ethanol productivities (about 3.30-6.31 g L(-1) h(-1)) were high and stable, and residual sugar concentrations were low in almost all fermentations (around 3.00 g L(-1)) with conversions ranging from 44.80% to 96.50%, showing efficiency (85.30-98.52%) and operational stability of the biocatalyst for ethanol fermentation. Results showed that cashew apple bagasse is an efficient support for cell immobilization aiming at ethanol production.

  18. Electrophoresis in strong electric fields.

    Science.gov (United States)

    Barany, Sandor

    2009-01-01

    Two kinds of non-linear electrophoresis (ef) that can be detected in strong electric fields (several hundred V/cm) are considered. The first ("classical" non-linear ef) is due to the interaction of the outer field with field-induced ionic charges in the electric double layer (EDL) under conditions, when field-induced variations of electrolyte concentration remain to be small comparatively to its equilibrium value. According to the Shilov theory, the non-linear component of the electrophoretic velocity for dielectric particles is proportional to the cubic power of the applied field strength (cubic electrophoresis) and to the second power of the particles radius; it is independent of the zeta-potential but is determined by the surface conductivity of particles. The second one, the so-called "superfast electrophoresis" is connected with the interaction of a strong outer field with a secondary diffuse layer of counterions (space charge) that is induced outside the primary (classical) diffuse EDL by the external field itself because of concentration polarization. The Dukhin-Mishchuk theory of "superfast electrophoresis" predicts quadratic dependence of the electrophoretic velocity of unipolar (ionically or electronically) conducting particles on the external field gradient and linear dependence on the particle's size in strong electric fields. These are in sharp contrast to the laws of classical electrophoresis (no dependence of V(ef) on the particle's size and linear dependence on the electric field gradient). A new method to measure the ef velocity of particles in strong electric fields is developed that is based on separation of the effects of sedimentation and electrophoresis using videoimaging and a new flowcell and use of short electric pulses. To test the "classical" non-linear electrophoresis, we have measured the ef velocity of non-conducting polystyrene, aluminium-oxide and (semiconductor) graphite particles as well as Saccharomice cerevisiae yeast cells as a

  19. Phytoremediation of Benzophenone and Bisphenol A by Glycosylation with Immobilized Plant Cells

    Directory of Open Access Journals (Sweden)

    Kei Shimoda

    2009-01-01

    Full Text Available Benzophenone and bisphenol A are environmental pollutions, which have been listed among “chemicals suspected of having endocrine disrupting effects” by the World Wildlife Fund, the National Institute of Environmental Health Sciences in the USA and the Japanese Environment Agency. The cultured cells of Nicotiana tabacum glycosylated benzophenone to three glycosides, 4-O-β-D-glucopyranosylbenzophenone (9%, diphenylmethyl β-D-glucopyranoside (14%, and diphenylmethyl 6-O-(β-D-glucopyranosyl-β-D-glucopyranoside (12% after 48 h incubation. On the other hand, incubation of benzophenone with immobilized cells of N. tabacum in sodium alginate gel gave products in higher yields, i.e. the yields of 4-O-β-D-glucopyranosylbenzophenone, diphenylmethyl β-D-glucopyranoside, and diphenylmethyl 6-O-(β-D-glucopyranosyl-β-D-glucopyranoside were 15, 27, and 22%, respectively. Bisphenol A was converted into three glycosides, 2,2-bis(4-β-D-glucopyranosyloxyphenylpropane (16%, 2-(4-β-D-glucopyranosyloxy-3-hydroxyphenyl-2-(4-β-D-gluco- pyranosyloxyphenyl propane (8%, and 2-(3-β-D-glucopyranosyloxy-4-hydroxyphenyl-2-(4-β-D-glucopyranosyloxyphe nylpropane (5%. Also the use of immobilized N. tabacum cells improved the yield of products; the glycosylation of bisphenol A with immobilized N. tabacum gave 2,2-bis(4-β-D-glucopyranosyloxyphenylpropane (24%, 2-(4-β-D-gluco- pyranosyloxy-3-hydroxyphenyl-2-(4-β-D-glucopyranosyloxyphenyl propane (15%, and 2-(3-β-D-glucopyranosyloxy- 4-hydroxyphenyl-2-(4-β-D-glucopyranosyloxyphenylpropane (11%.

  20. Immobilization of Electroporated Cells for Fabrication of Cellular Biosensors: Physiological Effects of the Shape of Calcium Alginate Matrices and Foetal Calf Serum

    Directory of Open Access Journals (Sweden)

    Nikos Katsanakis

    2009-01-01

    Full Text Available In order to investigate the physiological effect of transfected cell immobilization in calcium alginate gels, we immobilized electroporated Vero cells in gels shaped either as spherical beads or as thin membrane layers. In addition, we investigated whether serum addition had a positive effect on cell proliferation and viability in either gel configuration. The gels were stored for four weeks in a medium supplemented or not with 20% (v/v foetal calf serum. Throughout a culture period of four weeks, cell proliferation and cell viability were assayed by optical microscopy after provision of Trypan Blue. Non-elaborate culture conditions (room temperature, non-CO2 enriched culture atmosphere were applied throughout the experimental period in order to evaluate cell viability under less than optimal storage conditions. Immobilization of electroporated cells was associated with an initially reduced cell viability, which was gradually increased. Immobilization was associated with maintenance of cell growth for the duration of the experimental period, whereas electroporated cells essentially died after a week in suspension culture. Considerable proliferation of immobilized cells was observed in spherical alginate beads. In both gel configurations, addition of serum was associated with increased cell proliferation. The results of the present study could contribute to an improvement of the storability of biosensors based on electroporated, genetically or membrane-engineered cells.

  1. Preservation of Bacillus firmus Strain 37 and Optimization of Cyclodextrin Biosynthesis by Cells Immobilized on Loofa Sponge

    Directory of Open Access Journals (Sweden)

    Cristiane Moriwaki

    2012-08-01

    Full Text Available The preservation of Bacillus firmus strain 37 cells by lyophilization was evaluated and response surface methodology (RSM was used to optimize the β-cyclodextrin (β-CD production by cells immobilized on loofa sponge. Interactions were studied with the variables temperature, pH and dextrin concentration using a central composite design (CCD. Immobilization time influence on β-CD production was also investigated. B. firmus strain 37 cells remained viable after one year of storage, showing that the lyophilization is a suitable method for preservation of the microorganism. From the three-dimensional diagrams and contour plots, the best conditions for β-CD production were determined: temperature 60 °C, pH 8, and 18% dextrin. Considering that the amount of dextrin was high, a new assay was carried out, in which dextrin concentrations of 10, 15, and 18% were tested and the temperature of 60 °C and pH 8 were maintained. The results achieved showed very small differences and therefore, for economic reasons, the use of 10% dextrin is suggested. Increasing the immobilization time of cells immobilized on synthetic sponge the β-CD production decreased and did not change for cells immobilized on loofa sponge. The results of this research are important for microorganism preservation and essential in the optimization of the biosynthesis of CD.

  2. Enhancing osteogenic differentiation of MC3T3-E1 cells by immobilizing RGD onto liquid crystal substrate

    International Nuclear Information System (INIS)

    Wu, Shaopeng; Yang, Xiaohui; Li, Wenqiang; Du, Lin; Zeng, Rong; Tu, Mei

    2017-01-01

    To understand the effects of GRGDF modification on MC3T3-E1 cell behavior, we cultured these cells onto a biomimetic liquid crystalline matrix modified with GRGDF peptide (OPC-GA-RGD). Successful immobilization of GRGDF on the liquid crystalline surface was verified by fluorescent labeling, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). OPC-GA-RGDs retained its liquid crystalline feature after surface modification. The RGD-immobilized OPC substrate was hardly beneficial to initial cell adhesion but could support long-term cell survival. The enhancement in cell proliferation did not correlate with RGD density. The lower GRGDF density immobilized on the liquid crystalline OPC matrix (OPC-GA-RGD3) promoted cell adhesion, proliferation, ALP expression level and mineralization, suggesting that both the viscoelasticity-based mechanical stimuli and receptor/ligand-based biochemical cue synergistically modulate MC3T3-E1 cell behavior. - Highlight: • A novel type of GRGDF-immobilized liquid crystalline matrices was fabricated and served as a substrate for the in vitro culture of MC3T3-E1 cells. • The lower RGD density might provide a better condition for initial cell adhesion and proliferation, up-regulation of ALP expression levels, and mineralization. • The intrinsic liquid crystalline feature of OPC matrix, instead of RGD efficiency, promoted initial cell adhesion. • Properties of the liquid crystalline OPC matrix together with the stable receptor-ligand binging synergistically modulated MC3T3-E1 cell behavior.

  3. Enhancing osteogenic differentiation of MC3T3-E1 cells by immobilizing RGD onto liquid crystal substrate

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Shaopeng; Yang, Xiaohui; Li, Wenqiang; Du, Lin; Zeng, Rong; Tu, Mei, E-mail: tumei@jnu.edu.cn

    2017-02-01

    To understand the effects of GRGDF modification on MC3T3-E1 cell behavior, we cultured these cells onto a biomimetic liquid crystalline matrix modified with GRGDF peptide (OPC-GA-RGD). Successful immobilization of GRGDF on the liquid crystalline surface was verified by fluorescent labeling, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). OPC-GA-RGDs retained its liquid crystalline feature after surface modification. The RGD-immobilized OPC substrate was hardly beneficial to initial cell adhesion but could support long-term cell survival. The enhancement in cell proliferation did not correlate with RGD density. The lower GRGDF density immobilized on the liquid crystalline OPC matrix (OPC-GA-RGD3) promoted cell adhesion, proliferation, ALP expression level and mineralization, suggesting that both the viscoelasticity-based mechanical stimuli and receptor/ligand-based biochemical cue synergistically modulate MC3T3-E1 cell behavior. - Highlight: • A novel type of GRGDF-immobilized liquid crystalline matrices was fabricated and served as a substrate for the in vitro culture of MC3T3-E1 cells. • The lower RGD density might provide a better condition for initial cell adhesion and proliferation, up-regulation of ALP expression levels, and mineralization. • The intrinsic liquid crystalline feature of OPC matrix, instead of RGD efficiency, promoted initial cell adhesion. • Properties of the liquid crystalline OPC matrix together with the stable receptor-ligand binging synergistically modulated MC3T3-E1 cell behavior.

  4. Effect of hydrogel elasticity and ephrinB2-immobilized manner on Runx2 expression of human mesenchymal stem cells.

    Science.gov (United States)

    Toda, Hiroyuki; Yamamoto, Masaya; Uyama, Hiroshi; Tabata, Yasuhiko

    2017-08-01

    The objective of this study is to design the manner of ephrinB2 immobilized onto polyacrylamide (PAAm) hydrogels with varied elasticity and evaluate the effect of hydrogels elasticity and the immobilized manner of ephrinB2 on the Runx2 expression of human mesenchymal stem cells (hMSC). The PAAm hydrogels were prepared by the radical polymerization of acrylamide (AAm), and N,N'-methylenebisacrylamide (BIS). By changing the BIS concentration, the elasticity of PAAm hydrogels changed from 1 to 70kPa. For the bio-specific immobilization of ephrinB2, a chimeric protein of ephrinB2 and Fc domain was immobilized onto protein A-conjugated PAAm hydrogels by making use of the bio-specific interaction between the Fc domain and protein A. When hMSC were cultured on the ephrinB2-immobilized PAAm hydrogels with varied elasticity, the morphology of hMSC was of cuboidal shape on the PAAm hydrogels immobilized with ephrinB2 compared with non-conjugated ones, irrespective of the hydrogels elasticity. The bio-specific immobilization of ephrinB2 enhanced the level of Runx2 expression. The expression level was significantly high for the hydrogels of 3.6 and 5.9kPa elasticity with bio-specific immobilization of ephrinB2 compared with other hydrogels with the same elasticity. The hydrogels showed a significantly down-regulated RhoA activity. It is concluded that the Runx2 expression of hMSC is synergistically influenced by the hydrogels elasticity and their immobilized manner of ephrinB2 immobilized. Differentiation fate of mesenchymal stem cells (MSC) is modified by biochemical and biophysical factors, such as elasticity and signal proteins. However, there are few experiments about combinations of them. In this study, to evaluate the synergistic effect of them on cell properties of MSC, we established to design the manner of Eph signal ligand, ephrinB2, immobilized onto polyacrylamide hydrogels with varied elasticity. The gene expression level of an osteogenic maker, Runx2, was enhanced

  5. Removal of nitrate using Paracoccus sp. YF1 immobilized on bamboo carbon

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yan; Gan, Li [School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province (China); Chen, Zuliang, E-mail: Zuliang.chen@unisa.edu.au [School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province (China); Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of Environments, Mawson Lakes, SA 5095 (Australia); Megharaj, Mallavarapu; Naidu, Ravi [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of Environments, Mawson Lakes, SA 5095 (Australia)

    2012-08-30

    Highlights: Black-Right-Pointing-Pointer Paracoccus sp. immobilized on bamboo carbon used for the denitrification. Black-Right-Pointing-Pointer The rate of denitrification increased using the immobilized cells. Black-Right-Pointing-Pointer 99.8% denitrification was maintained after 10-cycle reuse. Black-Right-Pointing-Pointer Demonstrating an excellent reusability and a potential technique. - Abstract: Paracoccus sp. strain YF1 immobilized on bamboo carbon was developed for the denitrification. The results show that denitrification was significantly improved using immobilized cells compared to that of free cells, where denitrification time decreased from 24 h (free cells) to 15 h (immobilized cells). The efficiency of denitrification increased from 4.57 mg/(L h) (free cells) to 6.82 mg/(L h) (immobilized cells). Kinetics studies suggest that denitrification by immobilized YF1 cells fitted well to the zero-order model. Scanning electron microscopy (SEM) demonstrated that firstly, the bacteria became stable on the inside and exterior of the bamboo carbon particles and secondly, they formed biofilm after adhesion. Various factors and their influences on biological denitrification were investigated, namely temperature, pH, initial nitrate concentrations and carbon sources. The immobilized cells exhibited more nitrate removal at various conditions compared to free cells since bamboo carbon as a carrier protects cells against changes in environmental conditions. Denitrification using the YF1 immobilized in bamboo carbon was also maintained 99.8% after the tenth cycle reuse, thus demonstrating excellent reusability. Finally, wastewater was treated using the immobilized cells and the outcome was that nitrogen was completely removed by bamboo-immobilized YF1.

  6. Removal of nitrate using Paracoccus sp. YF1 immobilized on bamboo carbon

    International Nuclear Information System (INIS)

    Liu, Yan; Gan, Li; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravi

    2012-01-01

    Highlights: ► Paracoccus sp. immobilized on bamboo carbon used for the denitrification. ►The rate of denitrification increased using the immobilized cells. ► 99.8% denitrification was maintained after 10-cycle reuse. ► Demonstrating an excellent reusability and a potential technique. - Abstract: Paracoccus sp. strain YF1 immobilized on bamboo carbon was developed for the denitrification. The results show that denitrification was significantly improved using immobilized cells compared to that of free cells, where denitrification time decreased from 24 h (free cells) to 15 h (immobilized cells). The efficiency of denitrification increased from 4.57 mg/(L h) (free cells) to 6.82 mg/(L h) (immobilized cells). Kinetics studies suggest that denitrification by immobilized YF1 cells fitted well to the zero-order model. Scanning electron microscopy (SEM) demonstrated that firstly, the bacteria became stable on the inside and exterior of the bamboo carbon particles and secondly, they formed biofilm after adhesion. Various factors and their influences on biological denitrification were investigated, namely temperature, pH, initial nitrate concentrations and carbon sources. The immobilized cells exhibited more nitrate removal at various conditions compared to free cells since bamboo carbon as a carrier protects cells against changes in environmental conditions. Denitrification using the YF1 immobilized in bamboo carbon was also maintained 99.8% after the tenth cycle reuse, thus demonstrating excellent reusability. Finally, wastewater was treated using the immobilized cells and the outcome was that nitrogen was completely removed by bamboo-immobilized YF1.

  7. Immobilization method of yeast cells for intermittent contact mode imaging using the atomic force microscope

    International Nuclear Information System (INIS)

    De, Tathagata; Chettoor, Antony M.; Agarwal, Pranav; Salapaka, Murti V.; Nettikadan, Saju

    2010-01-01

    The atomic force microscope (AFM) is widely used for studying the surface morphology and growth of live cells. There are relatively fewer reports on the AFM imaging of yeast cells (Kasas and Ikai, 1995), (Gad and Ikai, 1995). Yeasts have thick and mechanically strong cell walls and are therefore difficult to attach to a solid substrate. In this report, a new immobilization technique for the height mode imaging of living yeast cells in solid media using AFM is presented. The proposed technique allows the cell surface to be almost completely exposed to the environment and studied using AFM. Apart from the new immobilization protocol, for the first time, height mode imaging of live yeast cell surface in intermittent contact mode is presented in this report. Stable and reproducible imaging over a 10-h time span is observed. A significant improvement in operational stability will facilitate the investigation of growth patterns and surface patterns of yeast cells.

  8. [Transformation of 2- and 4-cyanopyridines by free and immobilized cells of nitrile-hydrolyzing bacteria].

    Science.gov (United States)

    Maksimova, Iu G; Vasil'ev, D M; Ovechkina, G V; Maksimov, A Iu; Demakov, V A

    2013-01-01

    The transformation dynamics of 2- and 4-cyanopyridines by cells suspended and adsorbed on inorganic carriers has been studied in the Rhodococcus ruber gt 1 strain possessing nitrile hydratase activity and the Pseudomonas fluorescens C2 strain containing nitrilase. It was shown that both nitrile hydratase and nitrilase activities of immobilized cells against 2-cyanopyridine were 1.5-4 times lower compared to 4-cyanopyridine and 1.6-2 times lower than the activities of free cells against 2-cyanpopyridine. The possibility of obtaining isonicotinic acid during the combined conversion of 4-cyanopyridine by a mixed suspension of R. ruber gt 1 cells with a high level of nitrile hydratase activity and R. erythropolis 11-2 cells with a pronounced activity of amidase has been shown. Immobilization of Rhodococcus cells on raw coal and Pseudomonas cells on china clay was shown to yield a heterogeneous biocatalyst for the efficient transformation of cyanopyridines into respective amides and carbonic acids.

  9. Acetone-butanol-ethanol (ABE) fermentation in an immobilized cell trickle bed reactor.

    Science.gov (United States)

    Park, C H; Okos, M R; Wankat, P C

    1989-06-05

    Acetone-butanol-ethanol (ABE) fermentation was successfully carried out in an immobilized cell trickle bed reactor. The reactor was composed of two serial columns packed with Clostridium acetobutylicum ATCC 824 entrapped on the surface of natural sponge segments at a cell loading in the range of 2.03-5.56 g dry cells/g sponge. The average cell loading was 3.58 g dry cells/g sponge. Batch experiments indicated that a critical pH above 4.2 is necessary for the initiation of cell growth. One of the media used during continuous experiments consisted of a salt mixture alone and the other a nutrient medium containing a salt mixture with yeast extract and peptone. Effluent pH was controlled by supplying various fractions of the two different types of media. A nutrient medium fraction above 0.6 was crucial for successful fermentation in a trickle bed reactor. The nutrient medium fraction is the ratio of the volume of the nutrient medium to the total volume of nutrient plus salt medium. Supplying nutrient medium to both columns continuously was an effective way to meet both pH and nutrient requirement. A 257-mL reactor could ferment 45 g/L glucose from an initial concentration of 60 g/L glucose at a rate of 70 mL/h. Butanol, acetone, and ethanol concentrations were 8.82, 5.22, and 1.45 g/L, respectively, with a butanol and total solvent yield of 19.4 and 34.1 wt %. Solvent productivity in an immobilized cell trickle bed reactor was 4.2 g/L h, which was 10 times higher than that obtained in a batch fermentation using free cells and 2.76 times higher than that of an immobilized CSTR. If the nutrient medium fraction was below 0.6 and the pH was below 4.2, the system degenerated. Oxygen also contributed to the system degeneration. Upon degeneration, glucose consumption and solvent yield decreased to 30.9 g/L and 23.0 wt %, respectively. The yield of total liquid product (40.0 wt %) and butanol selectivity (60.0 wt %) remained almost constant. Once the cells were degenerated

  10. Effect of Ethanol Stress on Fermentation Performance of Saccharomyces cerevisiae Cells Immobilized on Nypa fruticans Leaf Sheath Pieces

    Directory of Open Access Journals (Sweden)

    Hoang Phong Nguyen

    2015-01-01

    Full Text Available The yeast cells of Saccharomyces cerevisiae immobilized on Nypa fruticans leaf sheath pieces were tested for ethanol tolerance (0, 23.7, 47.4, 71.0 and 94.7 g/L. Increase in the initial ethanol concentration from 23.7 to 94.7 g/L decreased the average growth rate and concentration of ethanol produced by the immobilized yeast by 5.2 and 4.1 times, respectively. However, in the medium with initial ethanol concentration of 94.7 g/L, the average growth rate, glucose uptake rate and ethanol formation rate of the immobilized yeast were 3.7, 2.5 and 3.5 times, respectively, higher than those of the free yeast. The ethanol stress inhibited ethanol formation by Saccharomyces cerevisiae cells and the yeast responded to the stress by changing the fatty acid composition of cellular membrane. The adsorption of yeast cells on Nypa fruticans leaf sheath pieces of the growth medium increased the saturated fatty acid (C16:0 and C18:0 mass fraction in the cellular membrane and that improved alcoholic fermentation performance of the immobilized yeast.

  11. Implementation of Microfluidic Chip Electrophoresis for the Detection of B-cell Clonality

    Directory of Open Access Journals (Sweden)

    Vazan M

    2016-04-01

    Full Text Available Introduction: A clonal population of B-cells is defined as those cells arising from the mitotic division of a single somatic cell with the same rearrangement of immunoglobulin genes. This gives rise to DNA markers for each individual lymphoid cell and its progenies and enables us to study clonality in different B-cell malignancies using multiplex polymerase chain reaction - PCR. The BIOMED-2 protocol has been implemented for clonality detection in lymphoproliferative diseases and exploits multiplex PCR reaction, subsequently analyzed by heteroduplex analysis (HDA using polyacrylamide gel electrophoresis (PAGE. With the advent of miniaturization and automation of molecular biology methods, lab-on-chip technologies were developed and replace partially the conventional approaches. We tested device for microfluidic chip, which is used for B-cells clonality analysis, using a PCR reaction for three subregions called frameworks (FR of the immunoglobulin heavy locus (IGH gene.

  12. Production of D-tagatose, a functional sweetener, utilizing alginate immobilized Lactobacillus fermentum CGMCC2921 cells.

    Science.gov (United States)

    Xu, Zheng; Li, Sha; Fu, Fenggen; Li, Guixiang; Feng, Xiaohai; Xu, Hong; Ouyang, Pingkai

    2012-02-01

    D-tagatose is a ketohexose that can be used as a novel functional sweetener in foods, beverages, and dietary supplements. This study was aimed at developing a high-yielding D-tagatose production process using alginate immobilized Lactobacillus fermentum CGMCC2921 cells. For the isomerization from D-galactose into D-tagatose, the immobilized cells showed optimum temperature and pH at 65 °C and 6.5, respectively. The alginate beads exhibited a good stability after glutaraldehyde treatment and retained 90% of the enzyme activity after eight cycles (192 h at 65 °C) of batch conversion. The addition of borate with a molar ratio of 1.0 to D-galactose led to a significant enhancement in the D-tagatose yield. Using commercial β-galactosidase and immobilized L. fermentum cells, D-tagatose was successfully obtained from lactose after a two-step biotransformation. The relatively high conversion rate and productivity from D-galactose to D-tagatose of 60% and 11.1 g l⁻¹ h⁻¹ were achieved in a packed-bed bioreactor. Moreover, lactobacilli have been approved as generally recognized as safe organisms, which makes this L. fermentum strain an attracting substitute for recombinant Escherichia coli cells among D-tagatose production progresses.

  13. Surface Charge Measurement of SonoVue, Definity and Optison: A Comparison of Laser Doppler Electrophoresis and Micro-Electrophoresis.

    Science.gov (United States)

    Ja'afar, Fairuzeta; Leow, Chee Hau; Garbin, Valeria; Sennoga, Charles A; Tang, Meng-Xing; Seddon, John M

    2015-11-01

    Microbubble (MB) contrast-enhanced ultrasonography is a promising tool for targeted molecular imaging. It is important to determine the MB surface charge accurately as it affects the MB interactions with cell membranes. In this article, we report the surface charge measurement of SonoVue, Definity and Optison. We compare the performance of the widely used laser Doppler electrophoresis with an in-house micro-electrophoresis system. By optically tracking MB electrophoretic velocity in a microchannel, we determined the zeta potentials of MB samples. Using micro-electrophoresis, we obtained zeta potential values for SonoVue, Definity and Optison of -28.3, -4.2 and -9.5 mV, with relative standard deviations of 5%, 48% and 8%, respectively. In comparison, laser Doppler electrophoresis gave -8.7, +0.7 and +15.8 mV with relative standard deviations of 330%, 29,000% and 130%, respectively. We found that the reliability of laser Doppler electrophoresis is compromised by MB buoyancy. Micro-electrophoresis determined zeta potential values with a 10-fold improvement in relative standard deviation. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  14. Bioleaching of Primary Nickel Ore Using Acidithiobacillus ferrooxidans LR Cells Immobilized in Glass Beads

    Directory of Open Access Journals (Sweden)

    Ellen Cristine Giese

    2015-06-01

    Full Text Available Sulphide minerals are one of the most important sources of value metals. For several years, a large number of hydrometallurgical and biotechnological processes have been developed to leach low-grade sulphide ores and the conditions are well established. However, the management of microorganisms in the bioleaching process is not easy to handle. In this paper, the use of immobilized cells of Acidithiobacillus ferrooxidans LR in glass beads in bioleaching of primary nickel ore was evaluated. The column experiments inoculated with immobilized cells of A. ferrooxidans LR showed the same efficiency than the conventional method using free cells and is promising for application on a larger scale as it ensuring integrity and activity of biomining microorganisms and reduce process costs. DOI: http://dx.doi.org/10.17807/orbital.v7i2.698 

  15. Specific proteins synthesized during the viral lytic cycle in vaccinia virus-infected HeLa cells: analysis by high-resolution, two-dimensional gel electrophoresis

    International Nuclear Information System (INIS)

    Carrasco, L.; Bravo, R.

    1986-01-01

    The proteins synthesized in vaccinia-infected HeLa cells have been analyzed at different times after infection by using two-dimensional gel electrophoresis. Vaccinia-infected cells present up to 198 polypeptides (138 acidic, isoelectric focusing; 60 basic, nonequilibrium pH gradient electrophoresis) not detected in control cells. Cells infected in the presence of cycloheximide show 81 additional polypeptides after cycloheximide removal, resulting in a total estimate of 279 proteins induced after vaccinia infection. The glycoproteins made at various time postinfection were also analyzed. At least 13 proteins labeled with [ 3 H]glucosamine were detected in vaccinia-infected HeLa cells

  16. Enhancing anticoagulation and endothelial cell proliferation of titanium surface by sequential immobilization of poly(ethylene glycol) and collagen

    International Nuclear Information System (INIS)

    Pan, Chang-Jiang; Hou, Yan-Hua; Ding, Hong-Yan; Dong, Yun-Xiao

    2013-01-01

    In the present study, poly(ethylene glycol) (PEG) and collagen I were sequentially immobilized on the titanium surface to simultaneously improve the anticoagulation and endothelial cell proliferation. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy analysis confirmed that PEG and collagen I were successfully immobilized on the titanium surface. Water contact angle results suggested the excellent hydrophilic surface after the immobilization. The anticoagulation experiments demonstrated that the immobilized PEG and collagen I on the titanium surface could not only obviously prevent platelet adhesion and aggregation but also prolong activated partial thromboplastin time (APTT), leading to the improved blood compatibility. Furthermore, immobilization of collagen to the end of PEG chain did not abate the anticoagulation. As compared to those on the pristine and PEG-modified titanium surfaces, endothelial cells exhibited improved proliferative profiles on the surface modified by the sequential immobilization of PEG and collagen in terms of CCK-8 assay, implying that the modified titanium may promote endothelialization without abating the blood compatibility. Our method may be used to modify the surface of blood-contacting biomaterials such as titanium to promote endothelialization and improve the anticoagulation, it may be helpful for development of the biomedical devices such as coronary stents, where endothelializaton and excellent anticoagulation are required.

  17. Raspberry wine fermentation with suspended and immobilized yeast cells of two strains of Saccharomyces cerevisiae.

    Science.gov (United States)

    Djordjević, Radovan; Gibson, Brian; Sandell, Mari; de Billerbeck, Gustavo M; Bugarski, Branko; Leskošek-Čukalović, Ida; Vunduk, Jovana; Nikićević, Ninoslav; Nedović, Viktor

    2015-01-01

    The objectives of this study were to assess the differences in fermentative behaviour of two different strains of Saccharomyces cerevisiae (EC1118 and RC212) and to determine the differences in composition and sensory properties of raspberry wines fermented with immobilized and suspended yeast cells of both strains at 15 °C. Analyses of aroma compounds, glycerol, acetic acid and ethanol, as well as the kinetics of fermentation and a sensory evaluation of the wines, were performed. All fermentations with immobilized yeast cells had a shorter lag phase and faster utilization of sugars and ethanol production than those fermented with suspended cells. Slower fermentation kinetics were observed in all the samples that were fermented with strain RC212 (suspended and immobilized) than in samples fermented with strain EC1118. Significantly higher amounts of acetic acid were detected in all samples fermented with strain RC212 than in those fermented with strain EC1118 (0.282 and 0.602 g/l, respectively). Slightly higher amounts of glycerol were observed in samples fermented with strain EC1118 than in those fermented with strain RC212. Copyright © 2014 John Wiley & Sons, Ltd.

  18. Continuous Production of Dextran from Immobilized Cells of Leuconostoc mesenteroides KIBGE HA1 Using Acrylamide as a Support

    OpenAIRE

    Qader, Shah Ali Ul; Aman, Afsheen; Azhar, Abid

    2011-01-01

    The cells of L. mesenteroides KIBGE HA1 were immobilized for the production of dextran on acrylamide gel and gel concentration was optimized for maximum entrapment. Sucrose at substrate concentration of 10% produced high yield of dextran at 25°C with a percent conversion of 5.82 while at 35°C it was 3.5. However, increasing levels of sucrose diminished dextran yields. The free cells stopped producing dextran after 144 h, while immobilized cells continued to produce dextran even after 480 h. M...

  19. Production of cellulase from immobilized Trichoderma reesei

    International Nuclear Information System (INIS)

    Kasai, Noboru; Tamada, Masao; Kumakura, Minoru

    1989-05-01

    This report completed the results that obtained on the study of the enzyme activity in the culture of immobilized Trichoderma reesei cells in flask scale (100ml) and bench scale (30l). In the flask scale culture, the batch and repeated batch culture were carried out, and in the bench scale culture, the batch, repeated batch and continuous culture were done by using a culture equipment that is an unit process of the bench scale test plant for saccharification of cellulosic wastes. The enzyme activity of the immobilized cells was higher than that of the intact cells in the flask scale culture and it was confirmed that the enzyme activity was not decreased on the repeated batch culture of six times even. In the bench scale culture, it was found that a optimum culture condition of the immobilized cells was not different from that of the free cells and the immobilized cells gave the enzyme solution with a high enzyme activity in the culture condition of 450rpm stirring speed and air supply of 0.1v/v/m above. The technique of the repeated batch and continuous culture for long times in bench scale without contamination was established. The enzyme activity of the immobilized cells in continuous culture became to be 85 % to that in batch culture and it was found that the enzyme solution with high enzyme activity was continuously obtained in the continuous culture for long times. (author)

  20. The Experimental Study of the Performance of Nano-Thin Polyelectrolyte Shell for Dental Pulp Stem Cells Immobilization.

    Science.gov (United States)

    Grzeczkowicz, A; Granicka, L H; Maciejewska, I; Strawski, M; Szklarczyk, M; Borkowska, M

    2015-12-01

    Carious is the most frequent disease of mineralized dental tissues which might result in dental pulp inflammation and mortality. In such cases an endodontic treatment is the only option to prolong tooth functioning in the oral cavity; however, in the cases of severe pulpitis, especially when complicated with periodontal tissue inflammation, the endodontic treatment might not be enough to protect against tooth loss. Thus, keeping the dental pulp viable and/or possibility of the reconstruction of a viable dental pulp complex, appears to become a critical factor for carious and/or pulp inflammation treatment. The nowadays technologies, which allow handling dental pulp stem cells (DPSC), seem to bring us closer to the usage of dental stem cells for tooth tissues reconstruction. Thus, DPSC immobilized within nano-thin polymeric shells, allowing for a diffusion of produced factors and separation from bacteria, may be considered as a cover system supporting technology of dental pulp reconstruction. The DPSC were immobilized using a layer-by-layer technique within nano-thin polymeric shells constructed and modified by nanostructure involvement to ensure the layers stability and integrity as well as separation from bacterial cells. The cytotoxity of the material used for membrane production was assessed on the model of adherent cells. The performance of DPSC nano-coating was assessed in vitro. Membrane coatings showed no cytotoxicity on the immobilized cells. The presence of coating shell was confirmed with flow cytometry, atomic force microscopy and visualized with fluorescent microscopy. The transfer of immobilized DPSC within the membrane system ensuring cells integrity, viability and protection from bacteria should be considered as an alternative method for dental tissues transportation and regeneration.

  1. Removal of Cadmium and Zinc from Soil using Immobilized Cell of Biosurfactant Producing Bacteria

    Directory of Open Access Journals (Sweden)

    Charoon Sarin

    2010-07-01

    Full Text Available Immobilized biosurfactant producing bacteria (Bacillus subtilis TP8 and Pseudomonas fluorescens G7 were assessed for survival in heavy metal contaminated soil and for their ability to remove cadmium and zinc from contaminated soil. P. fluorescens G7 was considered to be a good candidate for bioremediation of heavy metals because of its high minimum inhibitory concentrations (MIC for each heavy metal and because of the obviously increased numbers of cell surviving after incubation in the heavy metal contaminated soil up to 4 weeks. The results of soil remediation showed that approximately 19% of Zn and 16.7% of Cd could be removed by this immobilized biosurfactant producing bacteria after incubation for 2 weeks. The results confirm the potential applicability of the immobilized biosurfactant producing bacteria for heavy metal bioremediation.

  2. Cell-Free Expression and In Situ Immobilization of Parasite Proteins from Clonorchis sinensis for Rapid Identification of Antigenic Candidates.

    Directory of Open Access Journals (Sweden)

    Christy Catherine

    Full Text Available Progress towards genetic sequencing of human parasites has provided the groundwork for a post-genomic approach to develop novel antigens for the diagnosis and treatment of parasite infections. To fully utilize the genomic data, however, high-throughput methodologies are required for functional analysis of the proteins encoded in the genomic sequences. In this study, we investigated cell-free expression and in situ immobilization of parasite proteins as a novel platform for the discovery of antigenic proteins. PCR-amplified parasite DNA was immobilized on microbeads that were also functionalized to capture synthesized proteins. When the microbeads were incubated in a reaction mixture for cell-free synthesis, proteins expressed from the microbead-immobilized DNA were instantly immobilized on the same microbeads, providing a physical linkage between the genetic information and encoded proteins. This approach of in situ expression and isolation enables streamlined recovery and analysis of cell-free synthesized proteins and also allows facile identification of the genes coding antigenic proteins through direct PCR of the microbead-bound DNA.

  3. Comparative investigations of T cell receptor gamma gene rearrangements in frozen and formalin-fixed paraffin wax-embedded tissues by capillary electrophoresis

    DEFF Research Database (Denmark)

    Christensen, M; Funder, A D; Bendix, K

    2006-01-01

    AIM: To compare clonal T cell receptor gamma (TCRgamma) gene rearrangements in frozen and formalin-fixed paraffin wax-embedded (FFPE) tissue, using capillary electrophoresis for use in diagnostics, as T cell lymphomas may be difficult to diagnose by conventional methods.METHODS: The DNA for PCR......% for patient specimens and the specificity 100%. The junctional region between the Vgamma and Jgamma segments was specific for each patient.CONCLUSIONS: Capillary electrophoresis of PCR products from frozen and FFPE tissue is suitable for detecting clonal TCRgamma gene rearrangements. It is important, however...

  4. Developing a capillary electrophoresis based method for dynamically monitoring enzyme cleavage activity using quantum dots-peptide assembly.

    Science.gov (United States)

    Wang, Jianhao; Fan, Jie; Liu, Li; Ding, Shumin; Liu, Xiaoqian; Wang, Jianpeng; Gao, Liqian; Chattopadhaya, Souvik; Miao, Peng; Xia, Jiang; Qiu, Lin; Jiang, Pengju

    2017-10-01

    Herein, a novel assay has been developed for monitoring PreScission protease (His-PSP) mediated enzyme cleavage of ATTO 590 labeled peptide substrate (ATTO-LEV). This novel method is based on combining the use of capillary electrophoresis and fluorescence detection (CE-FL) to dynamically monitor the enzyme cleavage activity. A multivalent peptide substrate was first constructed by immobilizing His-tagged ATTO 590 labeled peptide substrate (ATTO-LEVH6) onto the surface of CdSe/ZnS quantum dots (QDs). Once successfully immobilized, the novel multivalent peptide substrate resulted in the Förster resonance energy transfer (FRET) from QDs to ATTO 590. The ATTO-LEVH6-QD assembly was then incubated with His-PSP to study the proteolytic cleavage of surface bound ATTO-LEVH6 by CE-FL. Our data suggests that PreScission-mediated proteolytic cleavage is enzyme concentration- and incubation time-dependent. By combining capillary electrophoresis, QDs and FRET, our study herein not only provides a new method for the detection and dynamically monitoring of PSP enzyme cleavage activity, but also can be extended to the detection of many other enzymes and proteases. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Cell immobilization for production of lactic acid biofilms do it naturally.

    Science.gov (United States)

    Dagher, Suzanne F; Ragout, Alicia L; Siñeriz, Faustino; Bruno-Bárcena, José M

    2010-01-01

    Interest in natural cell immobilization or biofilms for lactic acid fermentation has developed considerably over the last few decades. Many studies report the benefits associated with biofilms as industrial methods for food production and for wastewater treatment, since the formation represents a protective means of microbial growth offering survival advantages to cells in toxic environments. The formation of biofilms is a natural process in which microbial cells adsorb to a support without chemicals or polymers that entrap the cells and is dependent on the reactor environment, microorganism, and characteristics of the support. These unique characteristics enable biofilms to cause chronic infections, disease, food spoilage, and devastating effects as in microbial corrosion. Their distinct resistance to toxicity, high biomass potential, and improved stability over cells in suspension make biofilms a good tool for improving the industrial economics of biological lactic acid production. Lactic acid bacteria and specific filamentous fungi are the main sources of biological lactic acid. Over the past two decades, studies have focused on improving the lactic acid volumetric productivity through reactor design development, new support materials, and improvements in microbial production strains. To illustrate the operational designs applied to the natural immobilization of lactic acid producing microorganisms, this chapter presents the results of a search for optimum parameters and how they are affected by the physical, chemical, and biological variables of the process. We will place particular emphasis upon the relationship between lactic acid productivity attained by various types of reactors, supports, media formulations, and lactic acid producing microorganisms. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  6. Cane molasses fermentation for continuous ethanol production in an immobilized cells reactor by Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Ghorbani, Farshid; Younesi, Habibollah; Esmaeili Sari, Abbas [Department of Environmental Science, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, P.O. Box: 64414-356 (Iran); Najafpour, Ghasem [Department of Chemical Engineering, Faculty of Engineering, Noshirvani University of Technology, Babol (Iran)

    2011-02-15

    Sodium-alginate immobilized yeast was employed to produce ethanol continuously using cane molasses as a carbon source in an immobilized cell reactor (ICR). The immobilization of Saccharomyces cerevisiae was performed by entrapment of the cell cultured media harvested at exponential growth phase (16 h) with 3% sodium alginate. During the initial stage of operation, the ICR was loaded with fresh beads of mean diameter of 5.01 mm. The ethanol production was affected by the concentration of the cane molasses (50, 100 and 150 g/l), dilution rates (0.064, 0.096, 0.144 and 0.192 h{sup -1}) and hydraulic retention time (5.21, 6.94, 10.42 and 15.63 h) of the media. The pH of the feed medium was set at 4.5 and the fermentation was carried out at an ambient temperature. The maximum ethanol production, theoretical yield (Y{sub E/S}), volumetric ethanol productivity (Q{sub P}) and total sugar consumption was 19.15 g/l, 46.23%, 2.39 g l{sup -1} h{sup -1} and 96%, respectively. (author)

  7. Radiation-induced DNA damage and repair in radiosensitive and radioresistant human tumour cells measured by field inversion gel electrophoresis

    International Nuclear Information System (INIS)

    Smeets, M.F.M.A.; Mooren, E.H.M.; Begg, A.C.

    1993-01-01

    Radiation-induced DNA damage induction and repair was measured in two human squamous carcinoma cell lines with differing radiosensitivities. Experiments were carried out with field inversion gel electrophoresis (FIGE), adapted to measure DNA double strand break (DSB) induction and repair in unlabelled cells. The sensitivity of the method was increased by introducing a hybridization membrane into the agarose gel. Damaged DNA accumulated on one spot on the membrane resulting in high local concentrations. This DNA was quantified using radioactively-labelled total human DNA as a probe. Radiosensitivity differences at physiological temperatures could not be explained by differences in either induction or repair of DNA damage as measured by pulsed field gel electrophoresis. (author)

  8. SDS-Polyacrylamide Electrophoresis and Western Blotting Applied to the Study of Asthma.

    Science.gov (United States)

    García-Solaesa, Virginia; Abad, Sara Ciria

    2016-01-01

    Western blotting is used to analyze proteins after being separated by electrophoresis and subsequently electro-transferred to a membrane. Once immobilized, a specific protein can be identified through its reaction with a labeled antibody or antigen. It is a methodology commonly used in biomedical research such as asthma studies, to assess the pathways of inflammatory mediators involved in the disease.Here, we describe an example of western blotting to determine the factors involved in asthma. In this chapter, the methodology of western blotting is reviewed, paying attention on potential problems and giving interesting recommendations.

  9. Continuous Ethanol Production Using Immobilized-Cell/Enzyme Biocatalysts in Fluidized-Bed Bioreactor (FBR)

    Energy Technology Data Exchange (ETDEWEB)

    Nghiem, NP

    2003-11-16

    The immobilized-cell fluidized-bed bioreactor (FBR) was developed at Oak Ridge National Laboratory (ORNL). Previous studies at ORNL using immobilized Zymomonas mobilis in FBR at both laboratory and demonstration scale (4-in-ID by 20-ft-tall) have shown that the system was more than 50 times as productive as industrial benchmarks (batch and fed-batch free cell fermentations for ethanol production from glucose). Economic analysis showed that a continuous process employing the FBR technology to produce ethanol from corn-derived glucose would offer savings of three to six cents per gallon of ethanol compared to a typical batch process. The application of the FBR technology for ethanol production was extended to investigate more complex feedstocks, which included starch and lignocellulosic-derived mixed sugars. Economic analysis and mathematical modeling of the reactor were included in the investigation. This report summarizes the results of these extensive studies.

  10. Soymilk residue (okara) as a natural immobilization carrier for Lactobacillus plantarum cells enhances soymilk fermentation, glucosidic isoflavone bioconversion, and cell survival under simulated gastric and intestinal conditions.

    Science.gov (United States)

    Xiudong, Xia; Ying, Wang; Xiaoli, Liu; Ying, Li; Jianzhong, Zhou

    2016-01-01

    Cell immobilization is an alternative to microencapsulation for the maintenance of cells in a liquid medium. However, artificial immobilization carriers are expensive and pose a high safety risk. Okara, a food-grade byproduct from soymilk production, is rich in prebiotics. Lactobacilli could provide health enhancing effects to the host. This study aimed to evaluate the potential of okara as a natural immobilizer for L. plantarum 70810 cells. The study also aimed to evaluate the effects of okara-immobilized L. plantarum 70810 cells (IL) on soymilk fermentation, glucosidic isoflavone bioconversion, and cell resistance to simulated gastric and intestinal stresses. Scanning electron microscopy (SEM) was used to show cells adherence to the surface of okara. Lactic acid, acetic acid and isoflavone analyses in unfermented and fermented soymilk were performed by HPLC with UV detection. Viability and growth kinetics of immobilized and free L. plantarum 70810 cells (FL) were followed during soymilk fermentation. Moreover, changes in pH, titrable acidity and viscosity were measured by conventional methods. For in vitro testing of simulated gastrointestinal resistance, fermented soymilk was inoculated with FL or IL and an aliquot incubated into acidic MRS broth which was conveniently prepared to simulate gastric, pancreatic juices and bile salts. Survival to simulated gastric and intestinal stresses was evaluated by plate count of colony forming units on MRS agar. SEM revealed that the lactobacilli cells attached and bound to the surface of okara. Compared with FL, IL exhibited a significantly higher specific growth rate, shorter lag phase of growth, higher productions of lactic and acetic acids, a faster decrease in pH and increase in titrable acidity, and a higher soymilk viscosity. Similarly, IL in soymilk showed higher productions of daizein and genistein compared with the control. Compared with FL, IL showed reinforced resistance to simulatedgastric and intestinal

  11. Soymilk residue (okara as a natural immobilization carrier for Lactobacillus plantarum cells enhances soymilk fermentation, glucosidic isoflavone bioconversion, and cell survival under simulated gastric and intestinal conditions

    Directory of Open Access Journals (Sweden)

    Xia Xiudong

    2016-11-01

    Full Text Available Cell immobilization is an alternative to microencapsulation for the maintenance of cells in a liquid medium. However, artificial immobilization carriers are expensive and pose a high safety risk. Okara, a food-grade byproduct from soymilk production, is rich in prebiotics. Lactobacilli could provide health enhancing effects to the host. This study aimed to evaluate the potential of okara as a natural immobilizer for L. plantarum 70810 cells. The study also aimed to evaluate the effects of okara-immobilized L. plantarum 70810 cells (IL on soymilk fermentation, glucosidic isoflavone bioconversion, and cell resistance to simulated gastric and intestinal stresses. Scanning electron microscopy (SEM was used to show cells adherence to the surface of okara. Lactic acid, acetic acid and isoflavone analyses in unfermented and fermented soymilk were performed by HPLC with UV detection. Viability and growth kinetics of immobilized and free L. plantarum 70810 cells (FL were followed during soymilk fermentation. Moreover, changes in pH, titrable acidity and viscosity were measured by conventional methods. For in vitro testing of simulated gastrointestinal resistance, fermented soymilk was inoculated with FL or IL and an aliquot incubated into acidic MRS broth which was conveniently prepared to simulate gastric, pancreatic juices and bile salts. Survival to simulated gastric and intestinal stresses was evaluated by plate count of colony forming units on MRS agar. SEM revealed that the lactobacilli cells attached and bound to the surface of okara. Compared with FL, IL exhibited a significantly higher specific growth rate, shorter lag phase of growth, higher productions of lactic and acetic acids, a faster decrease in pH and increase in titrable acidity, and a higher soymilk viscosity. Similarly, IL in soymilk showed higher productions of daizein and genistein compared with the control. Compared with FL, IL showed reinforced resistance to simulatedgastric and

  12. A novel cell weighing method based on the minimum immobilization pressure for biological applications

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Qili [Robotics and Mechatronics Research Laboratory, Department of Mechanical and Aerospace Engineering, Monash University, Clayton 3800 (Australia); Institute of Robotics and Automatic Information System, Nankai University, Tianjin 300071 (China); Shirinzadeh, Bijan [Robotics and Mechatronics Research Laboratory, Department of Mechanical and Aerospace Engineering, Monash University, Clayton 3800 (Australia); Cui, Maosheng [Biotechnology Lab of Animal Reproduction, Tianjin Animal Sciences, Tianjin 300112 (China); Sun, Mingzhu; Liu, Yaowei; Zhao, Xin, E-mail: zhaoxin@nankai.edu.cn [Institute of Robotics and Automatic Information System, Nankai University, Tianjin 300071 (China)

    2015-07-28

    A novel weighing method for cells with spherical and other regular shapes is proposed in this paper. In this method, the relationship between the cell mass and the minimum aspiration pressure to immobilize the cell (referred to as minimum immobilization pressure) is derived for the first time according to static theory. Based on this relationship, a robotic cell weighing process is established using a traditional micro-injection system. Experimental results on porcine oocytes demonstrate that the proposed method is able to weigh cells at an average speed of 16.3 s/cell and with a success rate of more than 90%. The derived cell mass and density are in accordance with those reported in other published results. The experimental results also demonstrated that this method is able to detect less than 1% variation of the porcine oocyte mass quantitatively. It can be conducted by a pair of traditional micropipettes and a commercial pneumatic micro-injection system, and is expected to perform robotic operation on batch cells. At present, the minimum resolution of the proposed method for measuring the cell mass can be 1.25 × 10{sup −15 }kg. Above advantages make it very appropriate for quantifying the amount of the materials injected into or moved out of the cells in the biological applications, such as nuclear enucleations and embryo microinjections.

  13. A novel cell weighing method based on the minimum immobilization pressure for biological applications

    International Nuclear Information System (INIS)

    Zhao, Qili; Shirinzadeh, Bijan; Cui, Maosheng; Sun, Mingzhu; Liu, Yaowei; Zhao, Xin

    2015-01-01

    A novel weighing method for cells with spherical and other regular shapes is proposed in this paper. In this method, the relationship between the cell mass and the minimum aspiration pressure to immobilize the cell (referred to as minimum immobilization pressure) is derived for the first time according to static theory. Based on this relationship, a robotic cell weighing process is established using a traditional micro-injection system. Experimental results on porcine oocytes demonstrate that the proposed method is able to weigh cells at an average speed of 16.3 s/cell and with a success rate of more than 90%. The derived cell mass and density are in accordance with those reported in other published results. The experimental results also demonstrated that this method is able to detect less than 1% variation of the porcine oocyte mass quantitatively. It can be conducted by a pair of traditional micropipettes and a commercial pneumatic micro-injection system, and is expected to perform robotic operation on batch cells. At present, the minimum resolution of the proposed method for measuring the cell mass can be 1.25 × 10 −15  kg. Above advantages make it very appropriate for quantifying the amount of the materials injected into or moved out of the cells in the biological applications, such as nuclear enucleations and embryo microinjections

  14. Potato Processing Wastewater as a Substrate for Red Pigment Production from Immobilized Gamma-Irradiated Cells of Monascus purpureus

    International Nuclear Information System (INIS)

    Hazaa, M.A.; Shash, S.M.; Emam, D.A.; Youssef, B.M.; Khalaf, M.A.

    2009-01-01

    Although pigment production by Monascus spp. in chemically defined media is well documented (in submerged cultures and free cells), very few information is available about the use of agro-industrial wastes and immobilized cells. In this study immobilized irradiated spores (in sponge cubes) of M. purpureus (24 h age and 0.5 g cubes/50 ml medium) produced high amount of red pigment reached up to 2.32 g/I, after 4 days of incubation, compared with the amount of pigment produced by the free cells (1.84 g/I). Also, potato processing wastewater (PPW) was examined as the main culture medium for red pigment production by this fungus under optimizing culture conditions for repeated batches. The results showed that with irradiated immobilized cells, the maximum amount of red pigment production (1.96 g/I) was recorded at the second batch. Moreover, high reductions of biochemical oxygen demand (BOD); 82.6 % for this waste was obtained during the second batch. The data revealed that very little amount of soluble toxic substances in the extracted sample leading to only 8% dead chicken embryos

  15. Effects of interferon gamma on Chlamydia trachomatis serovar A and L2 protein expression investigated by two-dimensional gel electrophoresis

    DEFF Research Database (Denmark)

    Shaw, A; Christiansen, Gunna; Birkelund, Svend

    1999-01-01

    ]methionine and two-dimensional gel electrophoresis with immobilized pH gradients in order to investigate changes in the protein expression of C. trachomatis serovar A and L2 caused by treatment with IFN-gamma. In contrast to what was observed in C. trachomatis L2, our results showed that, in C. trachomatis A, down...

  16. Exploring bio-hydrogen-producing performance in three-phase fluidized bed bioreactors using different types of immobilized cells

    International Nuclear Information System (INIS)

    Shu-Yii Wu; Chi-Neng Lin; Yuan-Chang Shen; Shu-Yii Wu; Chiu-Yue Lin; Jo-Shu Chang

    2006-01-01

    In this study, the spherical activated carbon (AC) and silicone gel (SC) were used as the primary matrices to immobilize H 2 -producing activated sludge. The experiments were carried out in two different types of three-phase fluidized beds; namely, conventional fluidized bed reactor (FBR) and draft tube fluidized bed reactor (DTFBR). The solid volume of AC and SC immobilized cells was 10 vol.% for both FBR and DTFBR. Sucrose (at 20000 mg COD/l) was used as the carbon substrate for H 2 production. The H 2 -producing performance was examined at different hydraulic retention times (HRT = 8, 6, 4, 2, 1, and 0.5 h). The results show that the best volumetric H 2 production rate was 1.23 ± 0.08 l/h/l (HRT = 2 h) and 2.33 ± 0.22 l/h/l (HRT 0.5 h) for fluidized beds containing AC and SC immobilized cells, respectively. The highest H 2 yield was 3.37 mol H 2 /mol sucrose (HRT = 6 h) and 4.07 mol H 2 /mol sucrose (HRT = 4 h) for fluidized beds with AC and SC immobilized cells, respectively. The H 2 content in the biogas was stably maintained at 35% or higher for all the reactors, while the primary soluble metabolites in the cultures were acetic acid and butyric acid. (authors)

  17. Effect of photo-immobilization of epidermal growth factor on the cellular behaviors

    International Nuclear Information System (INIS)

    Ogiwara, Kazutaka; Nagaoka, Masato; Cho, Chong-Su; Akaike, Toshihiro

    2006-01-01

    We constructed photo-reactive epidermal growth factor (EGF) bearing p-azido phenylalanine at the C-terminal (HEGFP) by genetic engineering to investigate the possibility of immobilized EGF as a novel artificial extracellular matrix (ECM). The constructed recombinant protein was immobilized to glass surface by ultraviolet irradiation. A431 cells adhered both to HEGFP-immobilized and collagen-coated surfaces. Interaction between immobilized HEGFP and EGF receptors in the A431 cells was independent of Mg 2+ although integrin-mediated cell adhesion to natural ECMs is dependent on Mg 2+ . Phosphorylation of EGF receptors in A431 cells was induced by immobilized HEGFP as same as soluble EGF. DNA uptake of hepatocytes decreased by immobilized HEGFP whereas it increased by soluble EGF. Liver-specific functions of hepatocytes were maintained for 3 days by immobilized HEGFP whereas they were not maintained by soluble EGF, indicating that immobilized HEGFP follows different signal transduction pathway from soluble EGF

  18. Chitin hydrolysis assisted by cell wall degrading enzymes immobilized of Thichoderma asperellum on totally cinnamoylated D-sorbitol beads

    International Nuclear Information System (INIS)

    Fernandes, Kátia F.; Cortijo-Triviño, David; Batista, Karla A.; Ulhoa, Cirano J.; García-Ruiz, Pedro A.

    2013-01-01

    In this study, cell wall degrading enzymes produced by Thrichoderma asperellum (TCWDE) were immobilized on totally cinnamoylated D-sorbitol (TCNSO) beads and used for chitin hydrolysis. In order to optimize immobilization efficiency, the reaction time was varied from 2 to 12 h and reactions were conducted in the presence or absence of Na 2 SO 4 . Immobilized enzymes were analysed concerning to thermal and operational stability. Immobilization in presence of Na 2 SO 4 was 54% more efficient than immobilization in absence of salt. After optimization, 32% of the total enzyme offered was immobilized, with 100% of bounding efficiency, measured as the relation between protein and enzyme immobilized. Free and TCNSO–TCWDE presented very similar kinetics with maximum hydrolysis reached at 90 min of reaction. Thermal stability of both free and TCNSO–TCWDE was similar, with losses in activity after 55 °C. Moreover, free and TCNSO–TCWDE retained 100% activity after 3 h incubation at 55 °C. TCNSO–TCWDE were used in a bath-wise reactor during 14 cycles, producing 1825 μg of N-acetylglucosamine (NAG) maintaining 83% of initial activity. - Highlights: • TCWDE immobilized on TCNSO, a support with highly hydrophobic character • New immobilization strategy for immobilization on a hydrophobic support • TCNSO–TCWDE were retained during washes and during incubation at 55 °C for 3 h

  19. Chitin hydrolysis assisted by cell wall degrading enzymes immobilized of Thichoderma asperellum on totally cinnamoylated D-sorbitol beads

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Kátia F., E-mail: katia@icb.ufg.br [Departamento de Bioquímica e Biologia Molecular, Instituo de Ciências Biológicas, Universidade Federal de Goiás, Cx. Postal 131, 74001-970 Goiânia, GO (Brazil); Grupo de Química de Carbohidratos y Biotecnología de Alimentos (QCBA), Departamento de Química Orgánica, Facultad de Química, Universidad de Murcia, E-30100 Espinardo, Murcia (Spain); Cortijo-Triviño, David [Grupo de Química de Carbohidratos y Biotecnología de Alimentos (QCBA), Departamento de Química Orgánica, Facultad de Química, Universidad de Murcia, E-30100 Espinardo, Murcia (Spain); Batista, Karla A.; Ulhoa, Cirano J. [Departamento de Bioquímica e Biologia Molecular, Instituo de Ciências Biológicas, Universidade Federal de Goiás, Cx. Postal 131, 74001-970 Goiânia, GO (Brazil); García-Ruiz, Pedro A. [Grupo de Química de Carbohidratos y Biotecnología de Alimentos (QCBA), Departamento de Química Orgánica, Facultad de Química, Universidad de Murcia, E-30100 Espinardo, Murcia (Spain)

    2013-07-01

    In this study, cell wall degrading enzymes produced by Thrichoderma asperellum (TCWDE) were immobilized on totally cinnamoylated D-sorbitol (TCNSO) beads and used for chitin hydrolysis. In order to optimize immobilization efficiency, the reaction time was varied from 2 to 12 h and reactions were conducted in the presence or absence of Na{sub 2}SO{sub 4}. Immobilized enzymes were analysed concerning to thermal and operational stability. Immobilization in presence of Na{sub 2}SO{sub 4} was 54% more efficient than immobilization in absence of salt. After optimization, 32% of the total enzyme offered was immobilized, with 100% of bounding efficiency, measured as the relation between protein and enzyme immobilized. Free and TCNSO–TCWDE presented very similar kinetics with maximum hydrolysis reached at 90 min of reaction. Thermal stability of both free and TCNSO–TCWDE was similar, with losses in activity after 55 °C. Moreover, free and TCNSO–TCWDE retained 100% activity after 3 h incubation at 55 °C. TCNSO–TCWDE were used in a bath-wise reactor during 14 cycles, producing 1825 μg of N-acetylglucosamine (NAG) maintaining 83% of initial activity. - Highlights: • TCWDE immobilized on TCNSO, a support with highly hydrophobic character • New immobilization strategy for immobilization on a hydrophobic support • TCNSO–TCWDE were retained during washes and during incubation at 55 °C for 3 h.

  20. Efficient biodegradation of cyanide and ferrocyanide by Na-alginate beads immobilized with fungal cells of Trichoderma koningii.

    Science.gov (United States)

    Zhou, Xiaoying; Liu, Lixing; Chen, Yunpeng; Xu, Shufa; Chen, Jie

    2007-09-01

    Cyanide or metal cyanide contaminations have become serious environmental and food-health problems. A fungal mutant of Trichoderma koningii, TkA8, constructed by restriction enzyme-mediated integration, has been verified to have a high cyanide degradation ability in our previous study. In this study, the mutant cells were entrapped in sodium-alginate (Na-alginate) immobilization beads to degrade cyanide and ferrocyanide in a liquid mineral medium. The results showed that the fungus in immobilization beads consisting of 3% Na-alginate and 3% CaCl2 could degrade cyanide more efficiently than a nonimmobilized fungal culture. For maximum degradation efficiency, the optimal ratio of Na-alginate and wet fungal biomass was 20:1 (m/m) and the initial pH was 6.5. In comparison, cell immobilization took at least 3 and 8 days earlier, respectively, to completely degrade cyanide and ferrocyanide. In addition, we showed that the immobilized beads could be easily recovered from the medium and reused for up to 5 batches without significant losses of fungal remediation abilities. The results of this study provide a promising alternative method for the large-scale remediation of soil or water systems from cyanide contamination.

  1. Evaluation of co-immobilized lactobacillus delbrueckii with porous particles for lactic acid production

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H.; Seki, M.; Furusaki, S. [The University of Tokyo, Tokyo (Japan)

    1996-02-01

    Lactic acid production using co-immobilized L.defbrveckii with porous particles has been studied. The effect of co-immobilization with porous particles was verified by measuring the variations of both overall production rate of lactic acid and effective diffusion coefficient in the co-immobilized gel. The effective diffusion coefficient decreased with increasing cell concentration in the co-immobilized gel. However, in the high cell density regimes, the effective diffusion coefficient in co-immobilized gel was higher than that without co-immobilized porous particles. The optimal volume fraction of porous particles in the co-immobilizing gel beads leas estimated experimentally at about 10%(v/v). An approximately 30% increase of the overall production rate was obtained compared to the control culture. Mathematical analysis showed that by co-immobilizing cells with porous particles, the steady-state concentration profiles of proton and undissociated lactic acid changed favorably inside the gel beads. The result indicates that co-immobilization with porous particles is a useful method to improve fermentation efficiency in processes using immobilized cells. 19 refs., 8 figs.

  2. Characterization of Seed Storage Proteins from Chickpea Using 2D Electrophoresis Coupled with Mass Spectrometry

    OpenAIRE

    Singh, Pramod Kumar; Shrivastava, Nidhi; Chaturvedi, Krishna; Sharma, Bechan; Bhagyawant, Sameer S.

    2016-01-01

    Proteomic analysis was employed to map the seed storage protein network in landrace and cultivated chickpea accessions. Protein extracts were separated by two-dimensional gel electrophoresis (2D-GE) across a broad range 3.0–10.0 immobilized pH gradient (IPG) strips. Comparative elucidation of differentially expressed proteins between two diverse geographically originated chickpea accessions was carried out using 2D-GE coupled with mass spectrometry. A total of 600 protein spots were detected ...

  3. Progress in emerging techniques for characterization of immobilized viable whole-cell biocatalysts

    Czech Academy of Sciences Publication Activity Database

    Bučko, M.; Vikartovská, A.; Schenkmayerová, A.; Tkáč, J.; Filip, J.; Chorvát Jr., D.; Neděla, Vilém; Ansorge-Schumacher, M.B.; Gemeiner, P.

    2017-01-01

    Roč. 71, č. 11 (2017), s. 2309-2324 ISSN 0366-6352 Institutional support: RVO:68081731 Keywords : bioelectrocatalysis * imaging techniques * immobilized whole-cell biocatalyst * multienzyme cascade reactions * online kinetics Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering OBOR OECD: Bioprocessing technologies (industrial processes relying on biological agents to drive the process) biocatalysis, fermentation Impact factor: 1.258, year: 2016

  4. Disc electrophoresis and related techniques of polyacrylamide gel electrophoresis

    National Research Council Canada - National Science Library

    Maurer, H. R

    1971-01-01

    ..., enzymes, antingens and radioactively labelled materials, and detailed treatments of micro disc electrophoresis, preparative polyacrylamide gel electrophoresis and many other techniques for special problems...

  5. Ultrafast Capillary Electrophoresis Isolation of DNA Aptamer for the PCR Amplification-Based Small Analyte Sensing

    Directory of Open Access Journals (Sweden)

    Emmanuelle eFiore

    2015-08-01

    Full Text Available Here, we report a new homogeneous DNA amplification-based aptamer assay for small analyte sensing. The aptamer of adenosine chosen as the model analyte was split into two fragments able to assemble in the presence of target. Primers were introduced at extremities of one fragment in order to generate the amplifiable DNA component. The amount of amplifiable fragment was quantifiable by Real-Time Polymerase Chain Reaction (RT-PCR amplification and directly reliable on adenosine concentration. This approach combines the very high separation efficiency and the homogeneous format (without immobilization of capillary electrophoresis and the sensitivity of real time PCR amplification. An ultrafast isolation of target-bound split aptamer (60 s was developed by designing a capillary electrophoresis input/ouput scheme. Such method was successfully applied to the determination of adenosine with a LOD of 1 µM.

  6. Application of the Single Cell Gel Electrophoresis (SCGE) Assay to Genotoxicity Evaluation in Plants and Animals

    International Nuclear Information System (INIS)

    Kim, Jin Kyu

    2007-10-01

    Application of the Single Cell Gel Electrophoresis (SCGE) Assay to Genotoxicity Evaluation in Plants and Animals. Recently, the importance of ionizing radiation and chemicals has been recognized since radio- and chemical therapy is directly related to the control of various diseases such as cancer. Radiation and the chemicals can cause biological damages while they have great applicability. It is of necessity to analyze rapidly, easily and accurately the biological effects, especially DNA damage due to those factors. Recently SCGE (single cell gel electrophoresis assay, alias comet assay) has been developed for the efficient evaluation of DNA damage. In this report, the comprehensive review will be given on the rationale, the technical applications and the advantages and shortcomings of SCGE assay. This method can be directly applied to study on toxicity, cancer, and aging in terms of the evaluation of DNA damages due to radiation and chemicals on human cellular level. It is also suggested that comet assay be used for testing genotoxicity of suspected substances, detecting irradiated foods, screening radioprotective candidates, and studying DNA repair process in various biological systems

  7. Application of the Single Cell Gel Electrophoresis (SCGE) Assay to Genotoxicity Evaluation in Plants and Animals

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Kyu

    2007-10-15

    Application of the Single Cell Gel Electrophoresis (SCGE) Assay to Genotoxicity Evaluation in Plants and Animals. Recently, the importance of ionizing radiation and chemicals has been recognized since radio- and chemical therapy is directly related to the control of various diseases such as cancer. Radiation and the chemicals can cause biological damages while they have great applicability. It is of necessity to analyze rapidly, easily and accurately the biological effects, especially DNA damage due to those factors. Recently SCGE (single cell gel electrophoresis assay, alias comet assay) has been developed for the efficient evaluation of DNA damage. In this report, the comprehensive review will be given on the rationale, the technical applications and the advantages and shortcomings of SCGE assay. This method can be directly applied to study on toxicity, cancer, and aging in terms of the evaluation of DNA damages due to radiation and chemicals on human cellular level. It is also suggested that comet assay be used for testing genotoxicity of suspected substances, detecting irradiated foods, screening radioprotective candidates, and studying DNA repair process in various biological systems.

  8. Whole cell immobilization of refractory glucose isomerase using tris(hydroxymethyl)phosphine as crosslinker for preparation of high fructose corn syrup at elevated temperature.

    Science.gov (United States)

    Jia, Dong-Xu; Wang, Teng; Liu, Zi-Jian; Jin, Li-Qun; Li, Jia-Jia; Liao, Cheng-Jun; Chen, De-Shui; Zheng, Yu-Guo

    2018-04-04

    Glucose isomerase (GI) responsible for catalyzing the isomerization from d-glucose to d-fructose, was an important enzyme for producing high fructose corn syrup (HFCS). In a quest to prepare HFCS at elevated temperature and facilitate enzymatic recovery, an effective procedure for whole cell immobilization of refractory Thermus oshimai glucose isomerase (ToGI) onto Celite 545 using tris(hydroxymethyl)phosphine (THP) as crosslinker was established. The immobilized biocatalyst showed an activity of approximate 127.3 U/(g·immobilized product) via optimization in terms of cells loading, crosslinker concentration and crosslinking time. The pH optimum of the immobilized biocatalyst was displaced from pH 8.0 of native enzyme to neutral pH 7.0. Compared with conventional glutaraldehyde (GLU)-immobilized cells, it possessed the enhanced thermostability with 70.1% residual activity retaining after incubation at 90°C for 72 h. Moreover, the THP-immobilized biocatalyst exhibited superior operational stability, in which it retained 85.8% of initial activity after 15 batches of bioconversion at 85°C. This study paved a way for reducing catalysis cost for upscale preparation of HFCS with higher d-fructose concentration. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  9. Immobilization of Glucose Oxidase on Modified-Carbon-Paste-Electrodes for Microfuel Cell

    Directory of Open Access Journals (Sweden)

    Laksmi Ambarsari

    2016-03-01

    Full Text Available Glucose oxidase (GOx is being developed for many applications such as an implantable fuel cell, due to its attractive property of operating under physiological conditions. This study reports the functional immobilization of glucose oxidase onto polyaniline-nanofiber-modified-carbon-paste-electrodes (GOx/MCPE as bioanodes in fuel cell applications. In particular, GOx is immobilized onto the electrode surface via a linker molecule (glutaraldehyde. Polyaniline, synthesized by the interfacial polymerization method, produces a morphological form of nanofibers (100-120 nm which have good conductivity. The performance of the polyaniline-modified-carbon-paste-electrode (MCPE was better than the carbon- paste-electrode (CPE alone. The optimal pH and temperature of the GOx/MCPE were 4.5 (in 100 mM acetate buffer and 65 °C, respectively. The GOx/MCPE exhibit high catalytic performances (activation energy 16.4 kJ mol-1, have a high affinity for glucose (Km value 37.79 µM and can have a maximum current (Imax of 3.95 mA. The sensitivity of the bioelectrode also was high at 57.79 mA mM-1 cm-2.

  10. Biological methanol production by immobilized Methylocella tundrae using simulated biohythane as a feed.

    Science.gov (United States)

    Patel, Sanjay K S; Singh, Raushan K; Kumar, Ashok; Jeong, Jae-Hoon; Jeong, Seong Hun; Kalia, Vipin C; Kim, In-Won; Lee, Jung-Kul

    2017-10-01

    Biohythane may be used as an alternative feed for methanol production instead of costly pure methane. In this study, methanol production potential of Methylocella tundrae immobilized through covalent immobilization, adsorption, and encapsulation was evaluated. Cells covalently immobilized on groundnut shells and chitosan showed a relative methanol production potential of 83.9 and 91.6%, respectively, compared to that of free cells. The maximum methanol production by free cells and cells covalently immobilized on groundnut shells and chitosan was 6.73, 6.20, and 7.23mM, respectively, using simulated biohythane as a feed. Under repeated batch conditions of eight cycles, cells covalently immobilized on chitosan and groundnut shells, and cells encapsulated in sodium-alginate resulted in significantly higher cumulative methanol production of 37.76, 31.80, and 25.58mM, respectively, than free cells (18.57mM). This is the first report on immobilization of methanotrophs on groundnut shells and its application in methanol production using biohythane as a feed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. An Evaluation of Kinetic Parameters of Cadmium and Copper Biosorption by Immobilized Cells

    Directory of Open Access Journals (Sweden)

    Nelly Georgieva

    2007-10-01

    Full Text Available Bioremediation is the use of living organisms to reduce or eliminate environmental hazards resulting from the accumulation of toxic chemicals and other hazardous wastes. This technology is based on the utilization of microorganisms to transform organic and inorganic compounds. The filamentous yeast Trichosporon cutaneum strain R57, immobilized and free cells was cultivated as batch culture on a liquid medium in the presence of various concentrations of cadmium and copper ions. The simultaneous uptake and accumulation of Cd2+ and Cu2+ ions by Tr. cutaneum cells depending on the initial concentration of Cd2+ and Cu2+ in the medium were studied. The potential use of the free and immobilized cells of Trichosporon cutaneum to remove cadmium and copper ions, from aqueous solutions was evaluated. Two important physicochemical aspects for the evaluation of the sorption process as a unit operation are the equilibrium of sorption and the kinetics. The Cd2+ and Cu2+ ions biosorption capacities of all tested adsorbent were presented as a function of the initial concentration of metal ions within the aqueous biosorption medium. The individual, as well as bicomponent sorption kinetics of copper and cadmium ions by immobilised cells of Trichosporon cutaneum R57 is presented. A second order kinetic model obtains kinetic parameters for the copper and cadmium ions.

  12. Binase Immobilized on Halloysite Nanotubes Exerts Enhanced Cytotoxicity toward Human Colon Adenocarcinoma Cells

    Directory of Open Access Journals (Sweden)

    Vera Khodzhaeva

    2017-09-01

    Full Text Available Many ribonucleases (RNases are considered as promising tools for antitumor therapy because of their selective cytotoxicity toward cancer cells. Binase, the RNase from Bacillus pumilus, triggers apoptotic response in cancer cells expressing RAS oncogene which is mutated in a large percentage of prevalent and deadly malignancies including colorectal cancer. The specific antitumor effect of binase toward RAS-transformed cells is due to its direct binding of RAS protein and inhibition of downstream signaling. However, the delivery of proteins to the intestine is complicated by their degradation in the digestive tract and subsequent loss of therapeutic activity. Therefore, the search of new systems for effective delivery of therapeutic proteins is an actual task. This study is aimed to the investigation of antitumor effect of binase immobilized on natural halloysite nanotubes (HNTs. Here, we have developed the method of binase immobilization on HNTs and optimized the conditions for the enzyme loading and release (i; we have found the non-toxic concentration of pure HNTs which allows to distinguish HNTs- and binase-induced cytotoxic effects (ii; using dark-field and fluorescent microscopy we have proved the absorption of binase-loaded HNTs on the cell surface (iii and demonstrated that binase-halloysite nanoformulations possessed twice enhanced cytotoxicity toward tumor colon cells as compared to the cytotoxicity of binase itself (iv. The enhanced antitumor activity of biocompatible binase-HNTs complex confirms the advisability of its future development for clinical practice.

  13. Comparison of non-electrophoresis grade with electrophoresis grade BIS in NIPAM polymer gel preparation

    Science.gov (United States)

    Khodadadi, Roghayeh; Khajeali, Azim; Farajollahi, Ali Reza; Hajalioghli, Parisa; Raeisi, Noorallah

    2015-01-01

    Introduction:The main objective of this study was to investigate the possibility of replacing electrophoresis cross-linker with non-electrophoresis N, N′-methylenebisacrylamide (BIS) in N-isopropyl acrylamide (NIPAM) polymer gel and its possible effect on dose response. Methods: NIPAM polymer gel was prepared from non-electrophoresis grade BIS and the relaxation rate (R2) was measured by MR imaging after exposing the gel to gamma radiation from Co-60 source. To compare the response of this gel with the one that contains electrophoresis grade BIS, two sets of NIPAM gel were prepared using electrophoresis and non-electrophoresis BIS and irradiated to different gamma doses. Results: It was found that the dose–response of NIPAM gel made from the non-electrophoresis grade BIS is coincident with that of electrophoresis grade BIS. Conclusion:Taken all, it can be concluded that the non-electrophoresis grade BIS not only is a suitable alternative for the electrophoresis grade BIS but also reduces the cost of gel due to its lower price. PMID:26457250

  14. Development in electrophoresis: instrumentation for two-dimensional gel electrophoresis of protein separation and application of capillary electrophoresis in micro-bioanalysis

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Aoshuang [Iowa State Univ., Ames, IA (United States)

    2008-01-01

    This dissertation begins with a general introduction of topics related to this work. The following chapters contain three scientific manuscripts, each presented in a separate chapter with accompanying tables, figures, and literature citations. The final chapter summarizes the work and provides some prospective on this work. This introduction starts with a brief treatment of the basic principles of electrophoresis separation, followed by a discussion of gel electrophoresis and particularly polyacrylamide gel electrophoresis for protein separation, a summary of common capillary electrophoresis separation modes, and a brief treatment of micro-bioanalysis application of capillary electrophoresis, and ends with an overview of protein conformation and dynamics.

  15. Determination of Concentration of Living Immobilized Yeast Cells by Fluorescence Spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Podrazký, Ondřej; Kuncová, Gabriela

    2005-01-01

    Roč. 107, č. 1 (2005), s. 126-134 ISSN 0925-4005. [European Conference on Optical Chemical Sensors and Biosensors EUROPT(R)ODE /7./. Madrid, 04.04.2004-07.04.2004] R&D Projects: GA ČR GA104/01/0461; GA MŠk(CZ) OC 840.10 Institutional research plan: CEZ:AV0Z40720504 Keywords : immobilization of cells * 2-D fluorescence spectroscopy * sol–gel Subject RIV: CE - Biochemistry Impact factor: 2.646, year: 2005

  16. Comparative analysis of different whole cell immobilized Aspergillus niger catalysts for gluconic acid fermentation using pretreated cane molasses

    Energy Technology Data Exchange (ETDEWEB)

    Subba Rao, D. (Div. of Biochemical Engineering, Dept. of Chemical Engineering, Indian Inst. of Tech., Madras (India)); Panda, T. (Div. of Biochemical Engineering, Dept. of Chemical Engineering, Indian Inst. of Tech., Madras (India))

    1994-10-01

    To compare the efficiency of various whole cell immobilization techniques for the production of gluconic acid by Aspergillus niger were investigated using potassium ferrocyanide-treated cane molasses as the substrate. The techniques followed were: (1) Calcium alginate entrapment, (2) cross-linking with glutaraldehyde after cell permeabilization with (a) acetone, (b) toluene and (c) isopropanol and (3) development of granular catalyst. A comparative analysis of yield has revealed that calcium alginate entrapment was the most suitable technique as it had given the maximum product yield (0.40 g gluconic acid/g total reducing sugar supplied). The properties of immobilized A. niger in sodium alginate gel have been thoroughly investigated and compared with those of free cells under most suitable conditions of fermentation. (orig.)

  17. Studies on the immobilization of biofunctional components by radiation polymerization and their applications

    International Nuclear Information System (INIS)

    Kaetsu, I.; Kumakura, M.; Fujimura, T.; Yoshida, M.; Asano, M.; Kasai, N.; Tamada, M.

    1986-01-01

    The recent progress on the studies of immobilization of various biofunctional components mainly by means of radiation polymerization as well as their practical applications to biomedical and biochemical fields were reviewed. The immobilization of drugs for the controlled release and targetting, the immobilization of antigens and antibodies for the immunodiagnosis, and the immobilization of microorganisms and tissue cells for the cell culture and the biomass conversion were the main topics in this review. The new findings on the enhanced immobilization methods and the polymeric carriers for immobilization were also attached. (author)

  18. Applications of space-electrophoresis in medicine. [for cellular separations in molecular biology

    Science.gov (United States)

    Bier, M.

    1976-01-01

    The nature of electrophoresis is reviewed and potential advances realizable in the field of biology and medicine from a space electrophoresis facility are examined. The ground-based applications of electrophoresis: (1) characterization of an ionized species; (2) determination of the quantitative composition of a complex mixture; and (3) isolation of the components of a mixture, separation achieved on the basis of the difference in transport rates is reviewed. The electrophoresis of living cells is considered, touching upon the following areas: the separation of T and B lymphocytes; the genetic influence on mouse lymphocyte mobilities; the abnormal production of specific and monoclonal immunoproteins; and the study of cancer. Schematic diagrams are presented of three types of electrophoresis apparatus: the column assembly for the static electrophoresis experiment on the Apollo-Soyuz mission, the continuous flow apparatus used in the same mission and a miniaturized electrophoresis apparatus.

  19. Affinity in electrophoresis.

    Science.gov (United States)

    Heegaard, Niels H H

    2009-06-01

    The journal Electrophoresis has greatly influenced my approaches to biomolecular affinity studies. The methods that I have chosen as my main tools to study interacting biomolecules--native gel and later capillary zone electrophoresis--have been the topic of numerous articles in Electrophoresis. Below, the role of the journal in the development and dissemination of these techniques and applications reviewed. Many exhaustive reviews on affinity electrophoresis and affinity CE have been published in the last few years and are not in any way replaced by the present deliberations that are focused on papers published by the journal.

  20. Continuous acetone-ethanol-butanol fermentation by immobilized cells of Clostridium acetobutylicum

    Energy Technology Data Exchange (ETDEWEB)

    Badr, H.R.; Toledo, R.; Hamdy, M.K. [University of Georgia, Athens (Greece). Food Science and Technology Dept.

    2001-07-01

    Eight Clostridium acetobutylicum strains were examined for {alpha}-amylase and strains B-591, B-594 and P-262 had the highest activities. Defibered-sweet-potato-slurry (DSPS), containing 39.7 g starch l{sup -1}, supplemented with potassium phosphate (1.0 g l{sup -1}), cysteine-HCl (5.0 g l{sup -1}), the antifoam (polypropylene glycol, 0.1 mg ml{sup -1}), was used a continuous feedstock (FS) to a multistage bioreactor system for acetone-ethanol-butanol (AEB) fermentation. The system consisted on four columns (three vertical and one near horizontal) packed with beads containing immobilized cells of C. acetobutylicum P-262. When DSPS was pumped into the bioreactor system, at a flow rate of 2.36 ml min{sup -1}, the effluent has 7.73 g solvents l{sup -1} (1.56, acetone; 0.65, ethanol; 5.52 g, butanol) and no starch. Productivity of total solvents synthesized during continuous operation were 1.0 g 1{sup -1}h{sup -1} and 19.5 % yield compared to 0.12 g l{sup -1}h{sup -1} with 29% yield using the batch system. We proposed using DSPS for AEB fermentation in a continuous mode with immobilized P-262 cells that are active amylase producers which will lead to cost reduction compared to the batch system. (Author)

  1. Immobilization of gold nanoparticles on cell culture surfaces for safe and enhanced gold nanoparticle-mediated laser transfection

    Science.gov (United States)

    Kalies, Stefan; Heinemann, Dag; Schomaker, Markus; Gentemann, Lara; Meyer, Heiko; Ripken, Tammo

    2014-01-01

    Abstract. In comparison to standard transfection methods, gold nanoparticle-mediated laser transfection has proven to be a versatile alternative. This is based on its minor influence on cell viability and its high efficiency, especially for the delivery of small molecules like small interfering RNA. However, in order to transfer it to routine usage, a safety aspect is of major concern: The avoidance of nanoparticle uptake by the cells is desired. The immobilization of the gold nanoparticles on cell culture surfaces can address this issue. In this study, we achieved this by silanization of the appropriate surfaces and the binding of gold nanoparticles to them. Comparable perforation efficiencies to the previous approaches of gold nanoparticle-mediated laser transfection with free gold nanoparticles are demonstrated. The uptake of the immobilized particles by the cells is unlikely. Consequently, these investigations offer the possibility of bringing gold nanoparticle-mediated laser transfection closer to routine usage. PMID:25069006

  2. Immobilization of Lactobacillus rhamnosus in mesoporous silica-based material: An efficiency continuous cell-recycle fermentation system for lactic acid production.

    Science.gov (United States)

    Zhao, Zijian; Xie, Xiaona; Wang, Zhi; Tao, Yanchun; Niu, Xuedun; Huang, Xuri; Liu, Li; Li, Zhengqiang

    2016-06-01

    Lactic acid bacteria immobilization methods have been widely used for lactic acid production. Until now, the most common immobilization matrix used is calcium alginate. However, Ca-alginate gel disintegrated during lactic acid fermentation. To overcome this deficiency, we developed an immobilization method in which Lactobacillus rhamnosus cells were successfully encapsulated into an ordered mesoporous silica-based material under mild conditions with a high immobilization efficiency of 78.77% by using elemental analysis. We also optimized the cultivation conditions of the immobilized L. rhamnosus and obtained a high glucose conversion yield of 92.4%. Furthermore, L. rhamnosus encapsulated in mesoporous silica-based material exhibited operational stability during repeated fermentation processes and no decrease in lactic acid production up to 8 repeated batches. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  3. Immobilization of yeast cells on hydrogel carriers obtained by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Luzhao Xin; Carenza, M.; Kaetsu, Isao; Kumakura, Minoru; Yoshida, Masaru; Fujimura, Takashi

    1992-01-01

    Polymer hydrogels were obtained by radiation-induced copolymerization at -78 o C of aqueous solutions of acrylic and methacrylic esters. The matrices were characterized by equilibrium water content measurements, by optical microscopy observations and by scanning electron microscopy analysis. Yeast cells were immobilized on these hydrogels and the ethanol productivity by batch fermentation was determined. Matrix hydrophilicity and porosity were found to deeply influence the adhesion of yeast cells and, hence, the ethanol productivity. The latter as well as other physico-chemical properties were also affected by the presence of a crosslinking agent added in small amounts to the polymerizating mixture. (author)

  4. Evaluation of genotoxicity of the acute gamma radiation on earthworm Eisenia fetida using single cell gel electrophoresis technique (Comet assay).

    Science.gov (United States)

    Sowmithra, K; Shetty, N J; Jha, S K; Chaubey, R C

    2015-12-01

    Earthworms (Eisenia fetida) most suitable biological indicators of radioactive pollution. Radiation-induced lesions in DNA can be considered to be molecular markers for early effects of ionizing radiation. Gamma radiation produces a wide spectrum of DNA. Some of these lesions, i.e., DNA strand breaks and alkali labile sites can be detected by the single-cell gel electrophoresis (SCGE) or comet assay by measuring the migration of DNA from immobilized nuclear DNA. E. fetida were exposed to different doses of gamma radiation, i.e., 1, 5, 10, 20, 30, 40 and 50Gy, and comet assay was performed for all the doses along with control at 1, 3 and 5h post irradiation to evaluate the genotoxicity of gamma radiation in this organism. The DNA damage was measured as percentage of comet tail DNA. A significant increase in DNA damage was observed in samples exposed to 5Gy and above, and the increase in DNA damage was dose dependent i.e., DNA damage was increased with increased doses of radiation. The highest DNA damage was noticed at 1h post irradiation and gradually decreased with time, i.e., at 3 and 5h post irradiation. The present study reveals that gamma radiation induces DNA damage in E. fetida and the comet assay is a sensitive and rapid method for its detection to detect genotoxicity of gamma radiation. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. KINETIC STUDIES ON BIODEGRADATION OF LIPIDS FROM OLIVE OIL MILL WASTEWATERS WITH FREE AND IMMOBILIZED Bacillus sp. CELLS

    Directory of Open Access Journals (Sweden)

    Anca-Irina Galaction

    2012-03-01

    Full Text Available The studies on the biodegradation of lipids from olive oil mill wastewater with free and immobilized Bacillus sp. cells indicated that the maximum specific rate of the process is reached at pH = 8. The use of immobilized cells allows to increasing the number of biodegradation process cycles, but reduces the rate of the process. In this case, the process rate depends on the biocatalysts size and cells concentration inside them. Thus, at bacterial cells concentration of 9 g d.w./100 mL biocatalyst, the apparent specific rate varied from 4.65 to 1.46×10-2 h-1 by increasing the biocatalyst particles diameter from 3 to 4.2 mm.The cumulated influences of the particles size and cells concentration have been included in a mathematical model for the apparent specific rate of lipids biodegradation. The model offers a good concordance with the experimental data, the average deviation being of +/- 7.38%.

  6. Preparation of nano-biomaterials with Leptolyngbia foveolarum and heavy metal biosorption by free and immobilized algal cells

    International Nuclear Information System (INIS)

    Toncheva-Panova, T.; Pouneva, I.; Sholeva, M.; Chernev, G.

    2010-01-01

    Using the sol-gel procedure nano-biomaterials with incorporation of Leptolyngbia foveolarum in the silica matrix were manufactured. The immobilization of algal cells was confirmed with Scanning Electron Microscopy (SEM) investigations and photos. Observation of nano-biomaterials with Atomic Force Microscopy (AFM) shows nanostructure with well-defined nanounits and their aggregates. The potential of the Antarctic isolate L. foveolarum for sorption of Cu 2+ and Cd 2+ was studied by incubation of free algal cells and those immobilized in nano-biomaterials in the salts solutions of the two heavy metals. The rest of the heavy metal was determined with inductively coupled plasma atomic emission spectrometer (ICP-AES). It was established that the heavy metal biosorption capacity demonstrated by the free Leptolyngbia cells was retained after their incorporation in the nano-matrices. Free cells as well as embedded in silica nano-matrix sequestered the two heavy metals with greater affinity for copper. The highest binding capacity, 76% of the initial Cu 2+ concentration possessed nano-biomaterials with incorporated vegetative L. foveolarum cells, compared to 68% of free cells. For cadmium the degree of biosorption was lower - 35% by free cells and 30.2% by those incorporated in the biocer. (authors)

  7. A chip-type thin-layer electrochemical cell coupled with capillary electrophoresis for online separation of electrode reaction products

    Energy Technology Data Exchange (ETDEWEB)

    He, Jian-Bo, E-mail: jbhe@hfut.edu.cn; Cui, Ting; Zhang, Wen-Wen; Deng, Ning

    2013-07-05

    Graphical abstract: -- Highlights: •A new coupling of thin-layer electrolysis with capillary electrophoresis (CE). •Rapid electrolysis, direct sampling followed by online CE separation. •At least 13 products of quercetin oxidation were separated. •Thermodynamic and kinetic parameters were determined from CE peak areas. -- Abstract: A coupling technique of thin-layer electrolysis with high-performance capillary electrophoresis/UV–vis technique(EC/HPCE/UV–vis) is developed for online separation and determination of electrode reaction products. A chip-type thin-layer electrolytic (CTE) cell was designed and fabricated, which contains a capillary channel and a background electrolyte reservoir, allowing rapid electrolysis, direct sampling and online electrophoretic separation. This chip-type setup was characterized based on an electrophoresis expression of Nernst equation that was applied to the redox equilibrium of o-tolidine at different potentials. The utility of the method was demonstrated by separating and determining the electro-oxidation products of quercetin in different pH media. Two main products were always found in the studied time, potential and pH ranges. The variety of products increased not only with increasing potential but also with increasing pH value, and in total, at least 13 products were observed in the electropherograms. This work illustrates a novel example of capillary electrophoresis used online with thin-layer electrolysis to separate and detect electrode reaction products.

  8. A chip-type thin-layer electrochemical cell coupled with capillary electrophoresis for online separation of electrode reaction products

    International Nuclear Information System (INIS)

    He, Jian-Bo; Cui, Ting; Zhang, Wen-Wen; Deng, Ning

    2013-01-01

    Graphical abstract: -- Highlights: •A new coupling of thin-layer electrolysis with capillary electrophoresis (CE). •Rapid electrolysis, direct sampling followed by online CE separation. •At least 13 products of quercetin oxidation were separated. •Thermodynamic and kinetic parameters were determined from CE peak areas. -- Abstract: A coupling technique of thin-layer electrolysis with high-performance capillary electrophoresis/UV–vis technique(EC/HPCE/UV–vis) is developed for online separation and determination of electrode reaction products. A chip-type thin-layer electrolytic (CTE) cell was designed and fabricated, which contains a capillary channel and a background electrolyte reservoir, allowing rapid electrolysis, direct sampling and online electrophoretic separation. This chip-type setup was characterized based on an electrophoresis expression of Nernst equation that was applied to the redox equilibrium of o-tolidine at different potentials. The utility of the method was demonstrated by separating and determining the electro-oxidation products of quercetin in different pH media. Two main products were always found in the studied time, potential and pH ranges. The variety of products increased not only with increasing potential but also with increasing pH value, and in total, at least 13 products were observed in the electropherograms. This work illustrates a novel example of capillary electrophoresis used online with thin-layer electrolysis to separate and detect electrode reaction products

  9. Detecting irradiation of seeds using microgel electrophoresis (a collaborative trial)

    International Nuclear Information System (INIS)

    Cerda, H.; Haine, H.E.; Jones, J.L.

    1995-06-01

    Preservation of certain foods by irradiation is permitted in the United Kingdom. However, all irradiated foods must be labelled as such, to ensure consumer choice. To help enforce labelling, a variety of methods have been developed for distinguishing between irradiated and non-irradiated foods. In preliminary trials, microgel electrophoresis -a simple method of assessing DNA damage - has shown considerable promise in this respect. This report describes microgel electrophoresis, and details results obtained in a blind trial carried out in collaboration with the Swedish University of Agricultural Sciences. Microgel electrophoresis facilitates analysis of the leakage of DNA from cells extracted from food material. In irradiated samples, the DNA is fragmented and will leak from cells in an electric current. This leakage can be seen as a 'comet' when the stained gel is viewed with a microscope. The size and shape of the comet can be used to estimate the irradiation dose administered to the sample. In non-irradiated samples the DNA is less fragmented, will tend not to leak from the cells and will not form a comet. (author)

  10. Radiation-induced DNA breaks detected by immuno labelling of poly(ADP-ribose) in CHO cells. Standardization by pulsed-field gel electrophoresis

    International Nuclear Information System (INIS)

    Varlet, P.; Bidon, N.; Noel, G.; Averbeck, D.; Salamero, J.; DeMurcia, G.

    1998-01-01

    The poly (ADP-ribose) polymerase is an ubiquitous nuclear protein capable of binding specifically to DNA strand breaks. It synthesizes ADP-ribose polymers proportionally to DNA breaks. The actual method of reference to determine DNA double strand breaks is pulsed-field gel electrophoresis, but this requires many cells. It thus appeared of interest to use poly (ADP-ribos)ylation to follow and estimate γ-ray-induced DNA fragmentation at the level of isolated cells after γ-irradiation in chinese hamster ovary cells (CHO-K1). The results obtained by the immuno-labelling technique of ADP-ribose polymers were compared to those obtained by pulsed-field gel electrophoresis. They show that poly (ADP-ribos)ylation reflects the occurrence of radiation-induced DNA strand breaks. A clear relationship exists between the amount of ADP-ribose polymers detected and DNA double strand breaks after γ-irradiation. (authors)

  11. Measurement of DNA double-strand breaks in CHO cells at various stages of the cell cycle using pulsed field gel electrophoresis: calibration by means of 125I decay

    International Nuclear Information System (INIS)

    Iliakis, G.E.; Cicilioni, O.; Metzger, L.

    1991-01-01

    Experiments were performed to calibrate a recently developed pulsed field gel electrophoresis assay, the asymmetric field inversion gel electrophoresis (AFIGE), for the measurement of double-strand breaks (dsb) in the DNA of mammalian cells. Calibration was carried out by means of 125 I decay accumulation, under conditions preventing repair, based on the observation that each 125 I decay in the DNA produces approximately one dsb. Results suggest that that observed fluctuations in the fraction of DNA activity released (FAR) per Gy throughout the cycle reflect cell-cycle-associated differences in the physicochemical properties of the DNA molecules that alter their electrophoretic mobility, rather than variations in the induction of dsb per Gy, i.e. the sensitivity of the assay fluctuates throughout the cycle. (author)

  12. Bioremediation of contaminated surface water by immobilized Micrococcus roseus.

    Science.gov (United States)

    Li, H; Li, P; Hua, T; Zhang, Y; Xiong, X; Gong, Z

    2005-08-01

    The problems caused by contaminated surface water have gradually become more serious in recent years. Although various remediation technologies were investigated, unfortunately, no efficient method was developed. In this paper, a new bioremediation technology was studied using Micrococcus roseus, which was immobilized in porous spherical beads by an improved polyvinyl alcohol (PVA) - sodium alginate (SA) embedding method. The experimental results indicated that COD removal rate could reach 64.7 % within 72 hours when immobilized M. roseus beads were used, which was ten times as high as that of free cells. The optimum inoculation rate of immobilized M. roseus beads was 10 % (mass percent of the beads in water sample, g g(-1)). Suitable aeration was proved necessary to enhance the bioremediation process. The immobilized cells had an excellent tolerance to pH and temperature changes, and were also more resistant to heavy metal stress compared with free cells. The immobilized M. roseus beads had an excellent regeneration capacity and could be reused after 180-day continuous usage. The Scanning Electronic Microscope (SEM) analysis showed that the bead microstructure was suitable for M. roseus growth, however, some defect structures should still be improved.

  13. Characterization of curdlan produced by Agrobacterium sp. IFO 13140 cells immobilized in a loofa sponge matrix, and application of this biopolymer in the development of functional yogurt.

    Science.gov (United States)

    Ortiz Martinez, Camila; Pereira Ruiz, Suelen; Carvalho Fenelon, Vanderson; Rodrigues de Morais, Gutierrez; Luciano Baesso, Mauro; Matioli, Graciette

    2016-05-01

    Agrobacterium sp. IFO 13140 cells were immobilized on a loofa sponge and used to produce curdlan over five successive cycles. The interaction between microbial cells and the loofa sponge as well as the produced curdlan were characterized by Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectrometry. The purity of the curdlan was also evaluated. The storage stability of the immobilized cells was assessed and the produced curdlan was used in a functional yogurt formulation. The average curdlan production by immobilized cells was 17.84 g L(-1) . The presence of the microorganism in the sponge was confirmed and did not cause alterations in the matrix, and the chemical structure of the curdlan was the same as that of commercial curdlan. The purity of both was similar. The immobilized cells remained active after 300 days of storage at -18 °C. The use of the produced curdlan in a functional yogurt resulted in a product with lower syneresis. A large number of cells physically adhered to the surface of loofa sponge fibers, and its use as an immobilization matrix to produce curdlan was effective. The use of the produced curdlan in yogurt allowed the development of a more stable product. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  14. Enhanced Uranium Immobilization and Reduction by Geobacter sulfurreducens Biofilms

    Science.gov (United States)

    Cologgi, Dena L.; Speers, Allison M.; Bullard, Blair A.; Kelly, Shelly D.

    2014-01-01

    Biofilms formed by dissimilatory metal reducers are of interest to develop permeable biobarriers for the immobilization of soluble contaminants such as uranium. Here we show that biofilms of the model uranium-reducing bacterium Geobacter sulfurreducens immobilized substantially more U(VI) than planktonic cells and did so for longer periods of time, reductively precipitating it to a mononuclear U(IV) phase involving carbon ligands. The biofilms also tolerated high and otherwise toxic concentrations (up to 5 mM) of uranium, consistent with a respiratory strategy that also protected the cells from uranium toxicity. The enhanced ability of the biofilms to immobilize uranium correlated only partially with the biofilm biomass and thickness and depended greatly on the area of the biofilm exposed to the soluble contaminant. In contrast, uranium reduction depended on the expression of Geobacter conductive pili and, to a lesser extent, on the presence of the c cytochrome OmcZ in the biofilm matrix. The results support a model in which the electroactive biofilm matrix immobilizes and reduces the uranium in the top stratum. This mechanism prevents the permeation and mineralization of uranium in the cell envelope, thereby preserving essential cellular functions and enhancing the catalytic capacity of Geobacter cells to reduce uranium. Hence, the biofilms provide cells with a physically and chemically protected environment for the sustained immobilization and reduction of uranium that is of interest for the development of improved strategies for the in situ bioremediation of environments impacted by uranium contamination. PMID:25128347

  15. Biological treatment of potato processing wastewater for red pigment production by immobilized cells of UV-irradiated monascus sp. in repeated batch

    International Nuclear Information System (INIS)

    Khalaf, S.A.

    2004-01-01

    Potato processing wastewater (PPW) was collected and analyzed for biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen and starch content. A fungal strain isolated from PPW identified as Monascus sp. PPW was evaluated for its ability to grow and produce red pigment, biomass and reduce the starch content of the ,PPW. Active UV-irradiated isolate of the above strain was obtained by exposing the parent strain to UV-radiation and coded Monascus. sp. PPW-UV7 and used as immobilized cell system for PPW treatment process in repeated batch fermentation. The immobilized cells (in sponge cubes) were able to reduce COD by about 85.7 %, with biomass production of 9.22 gl+ l and over productivity of red pigment of 2.6 gl+ 1 after 8 days fermentation (2 batches). The immobilized cells showed stability and viability for 8 batches (32 days) during the process treatment

  16. Single-cell gel electrophoresis applied to the analysis of UV-C damage and its repair in human cells

    International Nuclear Information System (INIS)

    Gedik, C.M.; Collins, A.R.; Ewen, S.W.B.

    1992-01-01

    The authors have adapted procedure of single cell gel electrophoresis (SCGE) for studying DNA damage and repair induced by UV-C-radiation, using HeLa cells. UV-C itself does not induce DNA breakage, and though cellular repair of UV-C damage produces DNA breaks as intermediates, these are too short-lived to be detected by SCGE. Incubation of UV-C-irradiated cells with the DNA synthesis inhibitor aphidicolin causes accumulation of incomplete repair sites to a level readily detected by SCGE even after doses as low as 0.5 J m -2 and incubation for as little as 5 min. The authors also studied UV-C-dependent incision, repair synthesis and ligation in permeable cells. Finally, key incubated permeable cells, after UV-C-irradiation, with exogenous UV endonuclease, examined consequent breaks both by SCGE and by alkaline unwinding to express results of the electrophoretic method in terms of DNA break frequencies. The sensitivity of the SCGE technique can thus be estimated; as few as 0.1 DNA breaks per 10 9 daltons are detected. (Author)

  17. Immobilization of Platelet-Rich Plasma onto COOH Plasma-Coated PCL Nanofibers Boost Viability and Proliferation of Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Anastasiya Solovieva

    2017-12-01

    Full Text Available The scaffolds made of polycaprolactone (PCL are actively employed in different areas of biology and medicine, especially in tissue engineering. However, the usage of unmodified PCL is significantly restricted by the hydrophobicity of its surface, due to the fact that its inert surface hinders the adhesion of cells and the cell interactions on PCL surface. In this work, the surface of PCL nanofibers is modified by Ar/CO2/C2H4 plasma depositing active COOH groups in the amount of 0.57 at % that were later used for the immobilization of platelet-rich plasma (PRP. The modification of PCL nanofibers significantly enhances the viability and proliferation (by hundred times of human mesenchymal stem cells, and decreases apoptotic cell death to a normal level. According to X-ray photoelectron spectroscopy (XPS, after immobilization of PRP, up to 10.7 at % of nitrogen was incorporated into the nanofibers surface confirming the grafting of proteins. Active proliferation and sustaining the cell viability on nanofibers with immobilized PRP led to an average number of cells of 258 ± 12.9 and 364 ± 34.5 for nanofibers with ionic and covalent bonding of PRP, respectively. Hence, our new method for the modification of PCL nanofibers with PRP opens new possibilities for its application in tissue engineering.

  18. Bioactivity of immobilized hyaluronic acid derivatives regarding protein adsorption and cell adhesion

    DEFF Research Database (Denmark)

    Köwitsch, Alexander; Yang, Yuan; Ma, Ning

    2011-01-01

    with HA on physicochemical surface properties of these substrata and estimates of the quantities of immobilized HA were obtained by different physical methods such as contact angle measurements, ellipsometry, and atomic force microscopy. The bioactivity of aHA and tHA toward their natural binding partner...... affects cell growth and differentiation. A lower number and spreading of cells were observed on HA-modified surfaces compared to amino- and vinyl-terminated glass and silicon surfaces. Immunofluorescence microscopy also revealed that adhesion of fibroblast plated on HA-modified surfaces was mediated...... primarily by HA receptor CD44, indicating that bioactivity of HA was not significantly reduced by chemical modification....

  19. Immobilization patterns and dynamics of acetate-utilizing methanogens immobilized in sterile granular sludge in upflow anaerobic sludge blanket reactors

    DEFF Research Database (Denmark)

    Schmidt, Jens Ejbye; Ahring, Birgitte Kiær

    1999-01-01

    Sterile granular sludge was inoculated with either Methanosarcina mazeii S-6, Methanosaeta concilii GP-6, or both species in acetate-fea upflow anaerobic sludge blanket (UASB) reactors to investigate the immobilization patterns and dynamics of aceticlastic methanogens in granular sludge. After......, but where the acetate concentration was low this strain was immobilized on support material as single cells or small clumps, The data clearly show that the two aceticlastic methanogens immobilize differently in UASB systems, depending on the conditions found throughout the UASB reactor....

  20. Covalent immobilization of stem cell factor and stromal derived factor 1α for in vitro culture of hematopoietic progenitor cells.

    Science.gov (United States)

    Cuchiara, Maude L; Horter, Kelsey L; Banda, Omar A; West, Jennifer L

    2013-12-01

    Hematopoietic stem cells (HSCs) are currently utilized in the treatment of blood diseases, but widespread application of HSC therapeutics has been hindered by the limited availability of HSCs. With a better understanding of the HSC microenvironment and the ability to precisely recapitulate its components, we may be able to gain control of HSC behavior. In this work we developed a novel, biomimetic PEG hydrogel material as a substrate for this purpose and tested its potential with an anchorage-independent hematopoietic cell line, 32D clone 3 cells. We immobilized a fibronectin-derived adhesive peptide sequence, RGDS; a cytokine critical in HSC self-renewal, stem cell factor (SCF); and a chemokine important in HSC homing and lodging, stromal derived factor 1α (SDF1α), onto the surfaces of poly(ethylene glycol) (PEG) hydrogels. To evaluate the system's capabilities, we observed the effects of the biomolecules on 32D cell adhesion and morphology. We demonstrated that the incorporation of RGDS onto the surfaces promotes 32D cell adhesion in a dose-dependent fashion. We also observed an additive response in adhesion on surfaces with RGDS in combination with either SCF or SDF1α. In addition, the average cell area increased and circularity decreased on gel surfaces containing immobilized SCF or SDF1α, indicating enhanced cell spreading. By recapitulating aspects of the HSC microenvironment using a PEG hydrogel scaffold, we have shown the ability to control the adhesion and spreading of the 32D cells and demonstrated the potential of the system for the culture of primary hematopoietic cell populations. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  1. Hydrolysis of whey by whole cells of Kluyveromyces bulgaricus immobilized in calcium alginate gels in hen egg white

    Energy Technology Data Exchange (ETDEWEB)

    Decleire, M; Huynh, N van; Motte, J C; Cat, W de

    1985-10-01

    Whey hydrolysis was compared in column reactors containing whole yeast cells immobilized in Ca-alginate or in hen egg white in relation to cell US -galactosidase activity, flow rates, temperature and time. With cells of 1.3 U/mg dry weight (ONPG method) immobilized in Ca-alignate, 80% hydrolysis was obtained at 4 and 20C with, respectively 0.50 and 1.65 bed volume/H; the values were 0.2 and 0.74 with cells entrapped in hen egg white. When the flow rate was expressed as ml/H/g wet yeast, no significant difference was observed between both matrices and 80% hydrolysis was reached with a flow rate 1.7 and 5 according to the temperature. The best performance was achieved by the yeast egg white reactor. At 4C, hydrolysis deccreased by 10% after 13 days; by 20% after 17 days. The presence of lactose transport inhibitors in whey did not significantly influence lactose hydrolysis. (orig.).

  2. Characterization of an immobilized cell, trickle bed reactor during long term butanol (ABE) fermentation.

    Science.gov (United States)

    Park, C H; Okos, M R; Wankat, P C

    1990-06-20

    Acetone-butanol-ethanol (ABE) fermentation was performed continuously in an immobilized cell, trickle bed reactor for 54 days without, degeneration by maintaining the pH above 4.3. Column clogging was minimized by structured packing of immobilization matrix. The reactor contained two serial glass columns packed with Clostridium acetobutylicum adsorbed on 12- and 20-in.-long polyester sponge strips at total flow rates between 38 and 98.7 mL/h. Cells were initially grown at 20 g/L glucose resulting in low butanol (1.15 g/L) production encouraging cell growth. After the initial cell growth phase a higher glucose concentration (38.7 g/L) improved solvent yield from 13.2 to 24.1 wt%, and butanol production rate was the best. Further improvement in solvent yield and butanol production rate was not observed with 60 g/L of glucose. However, when the fresh nutrient supply was limited to only the first column, solvent yield increased to 27.3 wt% and butanol selectivity was improved to 0.592 as compared to 0.541 when fresh feed was fed to both columns. The highest butanol concentration of 5.2 g/L occurred at 55% conversion of the feed with 60 g/L glucose. Liquid product yield of immobilized cells approached the theoretical value reported in the literature. Glucose and product concentration profiles along the column showed that the columns can be divided into production and inhibition regions. The length of each zone was dependent upon the feed glucose concentration and feed pattern. Unlike batch fermentation, there was no clear distinction between acid and solvent production regions. The pH dropped, from 6.18-6.43 to 4.50-4.90 in the first inch of the reactor. The pH dropped further to 4.36-4.65 by the exit of the column. The results indicate that the strategy for long term stable operation with high solvent yield requires a structured packing of biologically stable porous matrix such as polyester sponge, a pH maintenance above 4.3, glucose concentrations up to 60 g/L and

  3. Kinetics of ethanol production by immobilized Kluyveromyces marxianus cells at varying sugar concentrations of Jerusalem artichoke juice

    Energy Technology Data Exchange (ETDEWEB)

    Bajpai, P.; Margaritis, A.

    1987-08-01

    Kinetics of ethanol fermentation at varying sugar concentrations of Jerusalem artichoke tuber extract has been studied using Kluyveromyces marxianus cells immobilized in calcium alginate gel beads. A maximum ethanol concentration of 111 g/l was achieved at an initial sugar concentration of 260 g/l in 20 hours, when the immobilized cell concentration in the calcium alginate beads was 53.3 g dry wt./l bead volume. Ethanol yield remained almost unaffected by initial sugar concentration up to 250 g/l and was found to be about 88% of the theoretical. Maximum rate of ethanol production decreased from 22.5 g ethanol/l/h to 10.5 g ethanol/l/h while the maximum rate of total sugars utilization decreased from 74.9 g sugars/l/h to 28.5 g sugars/l/h as the initial substrate concentration was increased from 100 to 300 g/l. The concentration of free cells in the fermentation broth was low.

  4. Fixed-bed biosorption of cadmium using immobilized Scenedesmus obliquus CNW-N cells on loofa (Luffa cylindrica) sponge.

    Science.gov (United States)

    Chen, Bor-Yann; Chen, Chun-Yen; Guo, Wan-Qian; Chang, Hao-Wei; Chen, Wen-Ming; Lee, Duu-Jong; Huang, Chieh-Chen; Ren, Nan-Qi; Chang, Jo-Shu

    2014-05-01

    A continuous fixed-bed biosorption process was established for cadmium (Cd) removal by Scenedesmus obliquus CNW-N (isolated from southern Taiwan) cells immobilized onto loofa sponge. This immobilized-cell biosorption process allows better recovery and reusability of the microalgal biomass. The growth of microalgae on the matrix support with appropriate nutrient supplementation could enhance the overall metal removal activity. Major operating parameters (e.g., feeding flow rate, cycle number of medium replacement, and particle diameter of the sponge) were studied for treatability evaluation. The most promising cell growth on the sponge support was obtained at a flow rate of 0.284 bed volume (BV)/min, sponge particle diameter of 1 cm, and with one cycle of medium replacement. The performance of fixed-bed biosorption (adsorption capacity of 38.4 mg, breakthrough time at 15.5 h) was achieved at a flow rate of 5 ml/min with an influent concentration of 7.5 mg Cd/l. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Phylogenetic reconstruction of South American felids defined by protein electrophoresis

    OpenAIRE

    Pecon Slattery, J.; Johnson, W. E.; Goldman, D.; O'Brien, S. J.

    1994-01-01

    Phylogenetic associations among six closely related South American felid species were defined by changes in protein-encoding gene loci. We analyzed proteins isolated from skin fibroblasts using two-dimensional electrophoresis and allozymes extracted from blood cells. Genotypes were determined for multiple individuals of ocelot, margay, tigrina, Geoffroy's cat, kodkod, and pampas cat at 548 loci resolved by two-dimensional electrophoresis and 44 allozyme loci. Phenograms were constructed using...

  6. Two-dimensional polyacrylamide gel electrophoresis of intracellular proteins

    International Nuclear Information System (INIS)

    Ojima, N.; Sakamoto, T.; Yamashita, M.

    1996-01-01

    Since two-dimensional electrophoresis was established by O'Farrell for analysis of intracellular proteins of Escherichia coli, it has been applied to separation of proteins of animal cells and tissues, and especially to identification of stress proteins. Using this technique, proteins are separated by isoelectric focusing containing 8 m urea in the first dimension and by SDS-PAGE in the second dimension. The gels are stained with Coomassie Blue R-250 dye, followed by silver staining. In the case of radio-labeled proteins, the gels are dried and then autoradiographed. In order to identify a specific protein separated by two-dimensional electrophoresis, a technique determining the N-terminal amino acid sequence of the protein has been developed recently. After the proteins in the gel were electrotransferred to a polyvinylidene difluoride membrane, the membrane was stained for protein with Commassie Blue and a stained membrane fragment was applied to a protein sequencer. Our recent studies demonstrated that fish cells newly synthesized various proteins in response to heat shock, cold nd osmotic stresses. For example, when cellular proteins extracted from cold-treated rainbow trout cells were subjected to two-dimensional gel electrophoresis, the 70 kDa protein was found to be synthesized during the cold-treatment. N-Terminal sequence analysis showed that the cold-inducible protein was a homolog of mammalian valosin-containing protein and yeast cell division cycle gene product CDC48p. Furthermore, the sequence data were useful for preparing PCR primers and a rabbit antibody against a synthetic peptide to analyze a role for the protein in the function of trout cells and mechanisms for regulation

  7. Trans-membrane electron transfer in red blood cells immobilized in a chitosan film on a glassy carbon electrode

    International Nuclear Information System (INIS)

    Yu, Chunmei; Wang, Li; Zhu, Zhenkun; Bao, Ning; Gu, Haiying

    2014-01-01

    We have studied the trans-membrane electron transfer in human red blood cells (RBCs) immobilized in a chitosan film on a glassy carbon electrode (GCE). Electron transfer results from the presence of hemoglobin (Hb) in the RBCs. The electron transfer rate (k s ) of Hb in RBCs is 0.42 s −1 , and <1.13 s −1 for Hb directly immobilized in the chitosan film. Only Hb molecules in RBCs that are closest to the plasma membrane and the surface of the electrode can undergo electron transfer to the electrode. The immobilized RBCs displayed sensitive electrocatalytic response to oxygen and hydrogen peroxide. It is believed that this cellular biosensor is of potential significance in studies on the physiological status of RBCs based on observing their electron transfer on the modified electrode. (author)

  8. Characterization of a frozen shoulder model using immobilization in rats.

    Science.gov (United States)

    Kim, Du Hwan; Lee, Kil-Ho; Lho, Yun-Mee; Ha, Eunyoung; Hwang, Ilseon; Song, Kwang-Soon; Cho, Chul-Hyun

    2016-12-08

    The objective of this study was to investigate serial changes for histology of joint capsule and range of motion of the glenohumeral joint after immobilization in rats. We hypothesized that a rat shoulder contracture model using immobilization would be capable of producing effects on the glenohumeral joint similar to those seen in patients with frozen shoulder. Sixty-four Sprague-Dawley rats were randomly divided into one control group (n = 8) and seven immobilization groups (n = 8 per group) that were immobilized with molding plaster for 3 days, or for 1, 2, 3, 4, 5, or 6 weeks. At each time point, eight rats were euthanized for histologic evaluation of the axillary recess and for measurement of the abduction angle. Infiltration of inflammatory cells was found in the synovial tissue until 2 weeks after immobilization. However, inflammatory cells were diminished and fibrosis was dominantly observed in the synovium and subsynovial tissue 3 weeks after immobilization. From 1 week after immobilization, the abduction angle of all immobilization groups at each time point was significantly lower than that of the control group. Our study demonstrated that a rat frozen shoulder model using immobilization generates the pathophysiologic process of inflammation leading to fibrosis on the glenohumeral joint similar to that seen in patients with frozen shoulder. This model was attained within 3 weeks after immobilization. It may serve as a useful tool to investigate pathogenesis at the molecular level and identify potential target genes that are involved in the development of frozen shoulder.

  9. Platform for immobilization and observation of subcellular processes

    Science.gov (United States)

    McKnight, Timothy E.; Kalluri, Udaya C.; Melechko, Anatoli V.

    2014-08-26

    A method of immobilizing matter for imaging that includes providing an array of nanofibers and directing matter to the array of the nanofibers. The matter is immobilized when contacting at least three nanofibers of the array of nanofibers simultaneously. Adjacent nanofibers in the array of nanofibers may be separated by a pitch as great as 100 microns. The immobilized matter on the array of nanofibers may then be imaged. In some examples, the matter may be cell matter, such as protoplasts.

  10. Graphene oxide as a sulfur immobilizer in high performance lithium/sulfur cells

    Science.gov (United States)

    Zhang, Yuegang; Cairns, Elton J.; Ji, Liwen; Rao, Mumin

    2017-06-06

    The loss of sulfur cathode material as a result of polysulfide dissolution causes significant capacity fading in rechargeable lithium/sulfur cells. Embodiments of the invention use a chemical approach to immobilize sulfur and lithium polysulfides via the reactive functional groups on graphene oxide. This approach obtains a uniform and thin (.about.tens of nanometers) sulfur coating on graphene oxide sheets by a chemical reaction-deposition strategy and a subsequent low temperature thermal treatment process. Strong interaction between graphene oxide and sulfur or polysulfides demonstrate lithium/sulfur cells with a high reversible capacity of 950-1400 mAh g.sup.-1, and stable cycling for more than 50 deep cycles at 0.1 C.

  11. Graphene oxide as a sulfur immobilizer in high performance lithium/sulfur cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yuegang; Cairns, Elton J.; Ji, Liwen; Rao, Mumin

    2017-12-26

    The loss of sulfur cathode material as a result of polysulfide dissolution causes significant capacity fading in rechargeable lithium/sulfur cells. Embodiments of the invention use a chemical approach to immobilize sulfur and lithium polysulfides via the reactive functional groups on graphene oxide. This approach obtains a uniform and thin (.about.tens of nanometers) sulfur coating on graphene oxide sheets by a chemical reaction-deposition strategy and a subsequent low temperature thermal treatment process. Strong interaction between graphene oxide and sulfur or polysulfides demonstrate lithium/sulfur cells with a high reversible capacity of 950-1400 mAh g.sup.-1, and stable cycling for more than 50 deep cycles at 0.1 C.

  12. Tissue factor-expressing tumor cells can bind to immobilized recombinant tissue factor pathway inhibitor under static and shear conditions in vitro.

    Directory of Open Access Journals (Sweden)

    Sara P Y Che

    Full Text Available Mammary tumors and malignant breast cancer cell lines over-express the coagulation factor, tissue factor (TF. High expression of TF is associated with a poor prognosis in breast cancer. Tissue factor pathway inhibitor (TFPI, the endogenous inhibitor of TF, is constitutively expressed on the endothelium. We hypothesized that TF-expressing tumor cells can bind to immobilized recombinant TFPI, leading to arrest of the tumor cells under shear in vitro. We evaluated the adhesion of breast cancer cells to immobilized TFPI under static and shear conditions (0.35 - 1.3 dyn/cm2. We found that high-TF-expressing breast cancer cells, MDA-MB-231 (with a TF density of 460,000/cell, but not low TF-expressing MCF-7 (with a TF density of 1,400/cell, adhered to recombinant TFPI, under static and shear conditions. Adhesion of MDA-MB-231 cells to TFPI required activated factor VII (FVIIa, but not FX, and was inhibited by a factor VIIa-blocking anti-TF antibody. Under shear, adhesion to TFPI was dependent on the TFPI-coating concentration, FVIIa concentration and shear stress, with no observed adhesion at shear stresses greater than 1.0 dyn/cm2. This is the first study showing that TF-expressing tumor cells can be captured by immobilized TFPI, a ligand constitutively expressed on the endothelium, under low shear in vitro. Based on our results, we hypothesize that TFPI could be a novel ligand mediating the arrest of TF-expressing tumor cells in high TFPI-expressing vessels under conditions of low shear during metastasis.

  13. Flavor formation and cell physiology during the production of alcohol-free beer with immobilized Saccharomyces cerevisiae

    NARCIS (Netherlands)

    Iersel, van M.F.M.; Dieren, van B.; Rombouts, F.M.; Abee, T.

    1999-01-01

    Production of alcohol-free beer by limited fermentation is optimally performed in a packed-bed reactor operating in downflow. This ensures a highly controllable system with optimal reactor design. In the present study, we report on changes in the physiology of immobilized yeast cells in the reactor.

  14. Effective immobilization of alcohol dehydrogenase on carbon nanoscaffolds for ethanol biofuel cell.

    Science.gov (United States)

    Umasankar, Yogeswaran; Adhikari, Bal-Ram; Chen, Aicheng

    2017-12-01

    An efficient approach for immobilizing alcohol dehydrogenase (ADH) while enhancing its electron transfer ability has been developed using poly(2-(trimethylamino)ethyl methacrylate) (MADQUAT) cationic polymer and carbon nanoscaffolds. The carbon nanoscaffolds were comprised of single-walled carbon nanotubes (SWCNTs) wrapped with reduced graphene oxide (rGO). The ADH entrapped within the MADQUAT that was present on the carbon nanoscaffolds exhibited a high electron exchange capability with the electrode through its cofactor β-nicotinamide adenine dinucleotide hydrate and β-nicotinamide adenine dinucleotide reduced disodium salt hydrate (NAD + /NADH) redox reaction. The advantages of the carbon nanoscaffolds used as the support matrix and the MADQUAT employed for the entrapment of ADH versus physisorption were demonstrated via cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Our experimental results showed a higher electron transfer, electrocatalytic activity, and rate constant for MADQUAT entrapped ADH on the carbon nanoscaffolds. The immobilization of ADH using both MADQUAT and carbon nanoscaffolds exhibited strong potential for the development of an efficient bio-anode for ethanol powered biofuel cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Study on the non-target effect of ionizing radiation using single cell gel electrophoresis

    International Nuclear Information System (INIS)

    Wang Yan; Li Deguan; Liu Jianfeng; Chu Liping; Liu Qiang

    2008-01-01

    Objective: To assess the non-target effect of ionizing radiation by single cell gel electrophoresis (SCGE). Methods: Cross incubated the irradiated( 137 Cs; 2Gy) or non-irradiated lymphocytes of human peripheral blood in the irradiated or non-irradiated plasma respectively, then, assess the DNA damage of lymphocytes using SCGE analysis. Results: The lymphocytes incubated in the irradiated plasma presented more obvious DNA damage than the incubated in the non-irradiated plasma dose (P<0.05). Conclusion: The non-target effect of ionizing radiation can be assessed by SCGE, and the results confirm that cytokines may play a great role in it. (authors)

  16. Catalytical Properties of Free and Immobilized Aspergillus niger Tannase

    OpenAIRE

    Abril Flores-Maltos; Luis V. Rodríguez-Durán; Jacqueline Renovato; Juan C. Contreras; Raúl Rodríguez; Cristóbal N. Aguilar

    2011-01-01

    A fungal tannase was produced, recovered, and immobilized by entrapment in calcium alginate beads. Catalytical properties of the immobilized enzyme were compared with those of the free one. Tannase was produced intracellularly by the xerophilic fungus Aspergillus niger GH1 in a submerged fermentation system. Enzyme was recovered by cell disruption and the crude extract was partially purified. The catalytical properties of free and immobilized tannase were evaluated using tannic acid and methy...

  17. Immobilization Patterns and Dynamics of Acetate-Utilizing Methanogens Immobilized in Sterile Granular Sludge in Upflow Anaerobic Sludge Blanket Reactors

    Science.gov (United States)

    Schmidt, Jens Ejbye; Ahring, Birgitte Kjær

    1999-01-01

    Sterile granular sludge was inoculated with either Methanosarcina mazeii S-6, Methanosaeta concilii GP-6, or both species in acetate-fed upflow anaerobic sludge blanket (UASB) reactors to investigate the immobilization patterns and dynamics of aceticlastic methanogens in granular sludge. After several months of reactor operation, the methanogens were immobilized, either separately or together. The fastest immobilization was observed in the reactor containing M. mazeii S-6. The highest effluent concentration of acetate was observed in the reactor with only M. mazeii S-6 immobilized, while the lowest effluent concentration of acetate was observed in the reactor where both types of methanogens were immobilized together. No changes were observed in the kinetic parameters (Ks and μmax) of immobilized M. concilii GP-6 or M. mazeii S-6 compared with suspended cultures, indicating that immobilization does not affect the growth kinetics of these methanogens. An enzyme-linked immunosorbent assay using polyclonal antibodies against either M. concilii GP-6 or M. mazeii S-6 showed significant variations in the two methanogenic populations in the different reactors. Polyclonal antibodies were further used to study the spatial distribution of the two methanogens. M. concilii GP-6 was immobilized only on existing support material without any specific pattern. M. mazeii S-6, however, showed a different immobilization pattern: large clumps were formed when the concentration of acetate was high, but where the acetate concentration was low this strain was immobilized on support material as single cells or small clumps. The data clearly show that the two aceticlastic methanogens immobilize differently in UASB systems, depending on the conditions found throughout the UASB reactor. PMID:10049862

  18. IMPACT OF THE FERMENTATION PROCESS WITH IMMOBILIZED YEAST CELLS ON THE AROMA PROFILE AND SENSORY QUALITY OF DISTILLATES PRODUCED FROM TWO FIG (Ficus carica L. CULTIVARS

    Directory of Open Access Journals (Sweden)

    Borislav Miličević

    2017-01-01

    Full Text Available The aim of this research was to investigate the influence of immobilized cell fermentation on aroma and sensory characteristics of distillates produced from two fig varieties commonly grown in Croatia (Petrovača bijela and Petrovača crna. Distillate samples were produced both by classical and immobilized yeast fermentation technology. Aroma profile was determined using GC/FID and sensory analysis was conducted according to German DLG model. Results showed that immobilized cell technique gives distillates with higher ethanol and lower ester contents, but of higher sensory quality. It is a promising technique for production of high quality fruit distillates.

  19. Characteristics of an immobilized yeast cell system using very high gravity for the fermentation of ethanol.

    Science.gov (United States)

    Ji, Hairui; Yu, Jianliang; Zhang, Xu; Tan, Tianwei

    2012-09-01

    The characteristics of ethanol production by immobilized yeast cells were investigated for both repeated batch fermentation and continuous fermentation. With an initial sugar concentration of 280 g/L during the repeated batch fermentation, more than 98% of total sugar was consumed in 65 h with an average ethanol concentration and ethanol yield of 130.12 g/L and 0.477 g ethanol/g consumed sugar, respectively. The immobilized yeast cell system was reliable for at least 10 batches and for a period of 28 days without accompanying the regeneration of Saccharomyces cerevisiae inside the carriers. The multistage continuous fermentation was carried out in a five-stage column bioreactor with a total working volume of 3.75 L. The bioreactor was operated for 26 days at a dilution rate of 0.015 h(-1). The ethanol concentration of the effluent reached 130.77 g/L ethanol while an average 8.18 g/L residual sugar remained. Due to the high osmotic pressure and toxic ethanol, considerable yeast cells died without regeneration, especially in the last two stages, which led to the breakdown of the whole system of multistage continuous fermentation.

  20. The microalga Chlamydomonas reinhardtii CW-15 as a solar cell for hydrogen peroxide photoproduction. Comparison between free and immobilized cells and thylakoids for energy conversion efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Scholz, W.; Galvan, F.; Rosa, F.F. de la [Instituto de Bioquimica Vegetal y Fotosintesis, Universidad de Sevilla y CSIC, Sevilla (Spain)

    1995-11-28

    Immobilized cells and thylakoid vesicles of the microalga Chlamydomonas reinhardtii CW-15 have been developed as a solar cell because of their capabilities of producing hydrogen peroxide. This compound is an efficient and clean fuel used for rocket propulsion, motors and for heating. Hydrogen peroxide is produced by the photosystem in a catalyst cycle in which a redox mediator (methyl viologen) is reduced by electrons obtained from water by the photosynthetic apparatus of the microalga and it is re-oxidized by the oxygen dissolved in the solution. The photoproduction has been investigated using a discontinuous system with whole cells, or thylakoid vesicles, free or immobilized on alginate. The stimulation by azide as an inhibitor of catalase has also been analyzed. Under determined optimum conditions, the photoproduction by Ca-alginate entrapped cells, with a rate of 33 {mu}mol H{sub 2}O{sub 2}/mg Chl.h, was maintained for several hours with an energy conversion efficiency of 0.25%

  1. Preparation and immobilization of noble metal nanoparticles for plasmonic solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruoli; Pitzer, Martin; Hu, DongZhi; Schaadt, Daniel M. [Institut fuer Angewandte Physik, Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany); DFG Centrum fuer Funktionelle Nanostrukturen (CFN), KIT (Germany); Fruk, Ljiljana [DFG Centrum fuer Funktionelle Nanostrukturen (CFN), KIT (Germany)

    2011-07-01

    Thin-film solar cells are of high interest due to good electrical properties and low material consumption. Traditional thin-film cells, however, have considerable transmission losses because of the reduced absorption volume. A promising way to enhance absorption in the active layer is the light-trapping by plasmonic nanostructures. Metallic nanoparticles have in particular shown large enhancement of the photocurrent in thin-film devices. In this poster, we present preparation of Au,Ag and Pt nanoparticles by polyol method and seed mediated methods for use in plasmonic solar cells. Polyol method typically uses ethylene glycol as the solvent and reducing agent,and in seed-mediated synthesis small nanoparticle seeds are first prepared and then used to promote the growth of different shapes of nanoparticles. We particularly focus on the use of nanocubes and nanospheres for solar cell design. Following the nanoparticle preparation, a new method to immobilize particles on GaAs surfaces via covalent chemical bonds has been developed which prevents agglomerations and allows control of the surface density. Photocurrent spectra of GaAs pin solar cells with and without particles have been recorded. These measurements show the dependence of the photocurrent enhancement on particle material, shape and density.

  2. Comparative study of bio-ethanol production from mahula (Madhuca latifolia L.) flowers by Saccharomyces cerevisiae cells immobilized in agar agar and Ca-alginate matrices

    Energy Technology Data Exchange (ETDEWEB)

    Behera, Shuvashish; Mohanty, Rama Chandra [Department of Botany, Utkal University, Vani Vihar, Bhubaneswar 751004, Orissa (India); Kar, Shaktimay; Ray, Ramesh Chandra [Microbiology Laboratory, Central Tuber Crops Research Institute (Regional Centre), Bhubaneswar 751019, Orissa (India)

    2010-01-15

    Batch fermentation of mahula (Madhuca latifolia L., a tree commonly found in tropical rain forest) flowers was carried out using immobilized cells (in agar agar and calcium alginate) and free cells of Saccharomyces cerevisiae. The ethanol yields were 151.2, 154.5 and 149.1 g kg{sup -1} flowers using immobilized (in agar agar and calcium alginate) and free cells, respectively. Cell entrapment in calcium alginate was found to be marginally superior to those in agar agar (2.2% more) as well as over free cell (3.5% more) as regard to ethanol yield from mahula flowers is concerned. Further, the immobilized cells were physiologically active at least for three cycles [150.6, 148.5 and 146.5 g kg{sup -1} (agar agar) and 152.8, 151.5 and 149.5 g kg{sup -1} flowers (calcium alginate) for first, second and third cycle, respectively] of ethanol fermentation without apparently lowering the productivity. Mahula flowers, a renewable, non-food-grade cheap carbohydrate substrate from non-agricultural environment such as forest can serve as an alternative to food grade sugar/starchy crops such as maize, sugarcane for bio-ethanol production. (author)

  3. Continuous synthesis of glucoamylase by immobilized fungal mycelium of Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, T.E.; Jamuna, R.; Bansilal, C.V.; Ramakrishna, S.V. (Regional Research Lab., Trivandrum (India))

    1991-03-01

    The extracellular glucoamylase enzyme (EC 3.2.1.3) was synthesized continuously by the immobilized mycelial fragments of A. niger. Of the several polymeric matrices attempted for immobilization k-carrageenan and alginate were found to be the most effective. However, the enzyme activity exhibited by the immobilized mycelia (I.M.) was 15-20% lower than that of free cells under batch conditions. The immobilized cells have retained nearly the same enzymatic activity (120IU/g of I.M.) for 6 repeated batches and thereafter decline in activity was noticed. An aerated packed bed reactor with I.M. was operated continuously for 360 h. The volumetric productivity of the reactor was 1600IU/L/h for 192 h and reduced to 25% in 360 h. (orig.).

  4. Immobilization of Acetobacter sp. CCTCC M209061 for efficient asymmetric reduction of ketones and biocatalyst recycling.

    Science.gov (United States)

    Chen, Xiao-Hong; Wang, Xiao-Ting; Lou, Wen-Yong; Li, Ying; Wu, Hong; Zong, Min-Hua; Smith, Thomas J; Chen, Xin-De

    2012-09-04

    The bacterium Acetobacter sp. CCTCC M209061 is a promising whole-cell biocatalyst with exclusive anti-Prelog stereoselectivity for the reduction of prochiral ketones that can be used to make valuable chiral alcohols such as (R)-4-(trimethylsilyl)-3-butyn-2-ol. Although it has promising catalytic properties, its stability and reusability are relatively poor compared to other biocatalysts. Hence, we explored various materials for immobilizing the active cells, in order to improve the operational stability of biocatalyst. It was found that Ca-alginate give the best immobilized biocatalyst, which was then coated with chitosan to further improve its mechanical strength and swelling-resistance properties. Conditions were optimized for formation of reusable immobilized beads which can be used for repeated batch asymmetric reduction of 4'-chloroacetophenone. The optimized immobilized biocatalyst was very promising, with a specific activity of 85% that of the free-cell biocatalyst (34.66 μmol/min/g dw of cells for immobilized catalyst vs 40.54 μmol/min/g for free cells in the asymmetric reduction of 4'-chloroacetophenone). The immobilized cells showed better thermal stability, pH stability, solvent tolerance and storability compared with free cells. After 25 cycles reaction, the immobilized beads still retained >50% catalytic activity, which was 3.5 times higher than degree of retention of activity by free cells reused in a similar way. The cells could be recultured in the beads to regain full activity and perform a further 25 cycles of the reduction reaction. The external mass transfer resistances were negligible as deduced from Damkohler modulus Da internal mass transfer restriction affected the reduction action but was not the principal rate-controlling step according to effectiveness factors η < 1 and Thiele modulus 0.3<∅ <1. Ca-alginate coated with chitosan is a highly effective material for immobilization of Acetobacter sp. CCTCC M209061 cells for repeated use in

  5. Immobilization of Acetobacter sp. CCTCC M209061 for efficient asymmetric reduction of ketones and biocatalyst recycling

    Directory of Open Access Journals (Sweden)

    Chen Xiao-Hong

    2012-09-01

    Full Text Available Abstract Background The bacterium Acetobacter sp. CCTCC M209061 is a promising whole-cell biocatalyst with exclusive anti-Prelog stereoselectivity for the reduction of prochiral ketones that can be used to make valuable chiral alcohols such as (R-4-(trimethylsilyl-3-butyn-2-ol. Although it has promising catalytic properties, its stability and reusability are relatively poor compared to other biocatalysts. Hence, we explored various materials for immobilizing the active cells, in order to improve the operational stability of biocatalyst. Results It was found that Ca-alginate give the best immobilized biocatalyst, which was then coated with chitosan to further improve its mechanical strength and swelling-resistance properties. Conditions were optimized for formation of reusable immobilized beads which can be used for repeated batch asymmetric reduction of 4′-chloroacetophenone. The optimized immobilized biocatalyst was very promising, with a specific activity of 85% that of the free-cell biocatalyst (34.66 μmol/min/g dw of cells for immobilized catalyst vs 40.54 μmol/min/g for free cells in the asymmetric reduction of 4′-chloroacetophenone. The immobilized cells showed better thermal stability, pH stability, solvent tolerance and storability compared with free cells. After 25 cycles reaction, the immobilized beads still retained >50% catalytic activity, which was 3.5 times higher than degree of retention of activity by free cells reused in a similar way. The cells could be recultured in the beads to regain full activity and perform a further 25 cycles of the reduction reaction. The external mass transfer resistances were negligible as deduced from Damkohler modulus Da η ∅ Conclusions Ca-alginate coated with chitosan is a highly effective material for immobilization of Acetobacter sp. CCTCC M209061 cells for repeated use in the asymmetric reduction of ketones. Only a small cost in terms of the slightly lower catalytic activity compared to

  6. Application of single cell gel electrophoresis in post-evaluation of organism radiation damage

    International Nuclear Information System (INIS)

    Jiang Lin; Mu Wanjun; Liu Guoping; Xu Yunshu; Luo Shunzhong; Gao Qingxiang

    2009-01-01

    The transient irradiation-caused DNA damage in the human peripheral blood lymphocytes,mouse peripheral blood lymphocytes and alive mouse irradiated by α-ray and γ-ray was investigated, and the single cell gel electrophoresis(SCGE, Comet Assay) was used to detect the extent of DNA damage. On this basis, the dose-effect curve and the evaluating method for radiant after-effect were established, the absorbed dose of alive mouse A irradiated by γ-rays was computed. The results indicate that not only the dose-effect can be described by using SCGE, but also the dose-computed after organism irradiated by radiant rays is achieved with it, and SCGE may be used as a new biological dosimeter. (authors)

  7. Application of single cell gel electrophoresis in post-evaluation of organism radiation damage

    International Nuclear Information System (INIS)

    Jiang Lin; Mu Wanjun; Liu Guoping; Xu Yunshu; Gao Qingxiang

    2007-01-01

    The immediate irradiation-caused DNA damage in the human Peripheral Blood Lymphocytes, mouse Peripheral Blood Lymphocytes and alive mouse irradiated by α-Rays and γ-rays was investigated, and the single cell gel electrophoresis(SCGE, Comet Assay) was used to detect the extent of DNA damage. On this base, the dose-effect curve and the evaluating method for radiant aftereffect were established, the absorbed does of alive mouse A irradiated by γ-rays was computed. The results indicated that not only the does-effect could be described by using SCGE, but also the does-computed after organism irradiated by radiant rays was achieved with it, and SCGE might be used as a new biological dosimeter. (authors)

  8. Lectin affinity electrophoresis.

    Science.gov (United States)

    Kobayashi, Yuka

    2014-01-01

    An interaction or a binding event typically changes the electrophoretic properties of a molecule. Affinity electrophoresis methods detect changes in the electrophoretic pattern of molecules (mainly macromolecules) that occur as a result of biospecific interactions or complex formation. Lectin affinity electrophoresis is a very effective method for the detection and analysis of trace amounts of glycobiological substances. It is particularly useful for isolating and separating the glycoisomers of target molecules. Here, we describe a sensitive technique for the detection of glycoproteins separated by agarose gel-lectin affinity electrophoresis that uses antibody-affinity blotting. The technique is tested using α-fetoprotein with lectin (Lens culinaris agglutinin and Phaseolus vulgaris agglutinin)-agarose gels.

  9. Bioreporter pseudomonas fluorescens HK44 immobilized in a silica matrix

    Directory of Open Access Journals (Sweden)

    Trogl J.

    2003-01-01

    Full Text Available The bioluminescent bioreporter Pseudomonas fluorescens HK44, the whole cell bacterial biosensor that responds to naphthalene and its metabolites via the production of visible light, was immobilized into a silica matrix by the sol-gel technique. The bioluminescence intensities were measured in the maximum of the bioluminescence band at X = 500 nm. The immobilized cells (>105 cells per g silica matrix produced light after induction by salicylate (cone. > 10 g/l, naphthalene and aminobenzoic acid. The bioluminescence intensities induced by 2,3-dihydroxynaphthalene 3-hydroxybenzoic acid and 4-hydroxybenzoic acid were comparable to a negative control. The cells in the silica layers on glass slides produced light in response to the presence of an inductor at least 8 months after immobilization, and >50 induction cycles. The results showed that these test slides could be used as assays for the multiple determination of water pollution.

  10. Immobilization Technologies in Probiotic Food Production

    Directory of Open Access Journals (Sweden)

    Gregoria Mitropoulou

    2013-01-01

    Full Text Available Various supports and immobilization/encapsulation techniques have been proposed and tested for application in functional food production. In the present review, the use of probiotic microorganisms for the production of novel foods is discussed, while the benefits and criteria of using probiotic cultures are analyzed. Subsequently, immobilization/encapsulation applications in the food industry aiming at the prolongation of cell viability are described together with an evaluation of their potential future impact, which is also highlighted and assessed.

  11. Electrophoresis technology

    Science.gov (United States)

    Snyder, R. S.

    1985-01-01

    A new high resolution apparatus designed for space was built as a laboratory prototype. Using a moving wall with a low zeta potential coating, the major sources of flow distortion for an electrophoretic sample stream are removed. Highly resolved fractions, however, will only be produced in space because of the sensitivity of this chamber to buoyancy-induced convection in the laboratory. The second and third flights of the McDonnell Douglas Astronautics Corporation continuous flow electrophoresis system carried samples developed at MSFC intended to evaluate the broad capabilities of free flow electrophoresis in a reduced gravity environment. Biological model materials, hemoglobin and polystyrene latex microspheres, were selected because of their past use as electrophoresis standards and as visible markers for fluid flow due to electroosmosis, spacecraft acceleration or other factors. The dependence of the separation resolution on the properties of the sample and its suspension solution was assessed.

  12. Induction of DNA double-strand breaks by restriction enzymes in X-ray-sensitive mutant Chinese hamster ovary cells measured by pulsed-field gel electrophoresis

    International Nuclear Information System (INIS)

    Kinashi, Yuko; Nagasawa, Hatsumi; Little, J.B.; Okayasu, Ryuichi; Iliakis, G.E.

    1995-01-01

    This investigation was designed to determine whether the cytotoxic effects of different restriction endonucleases are related to the number and type of DNA double-strand breaks (DSBs) they produce. Chinese hamster ovary (CHO) K1 and xrs-5 cells, a radiosensitive mutant of CHO K1, were exposed to restriction endonucleases HaeIII, HinfI, PvuII and BamHI by electroporation. These enzymes represent both blunt and sticky end cutters with differing recognition sequence lengths. The number of DSBs was measured by pulsed-field gel electrophoresis (PFGE). Two forms of PFGE were employed: asymmetric field-inversion gel electrophoresis (AFIGE) for measuring the kinetics of DNA breaks by enzyme digestion and clamped homogeneous gel electrophoresis (CHEF) for examining the size distributions of damaged DNA. The amount of DNA damage induced by exposure to all four restriction enzymes was significantly greater in xrs-5 compared to CHO K1 cells, consistent with the reported DSB repair deficiency in these cells. Since restriction endonucleases produce DSBs alone as opposed to the various types of DNA damage induced by X rays, these results confirm that the repair defect in this mutant involves the rejoining of DSBs. Although the cutting frequency was directly related to the length of the recognition sequence for four restriction enzymes, there was no simple correlation between the cytotoxic effect and the amount of DNA damage produced by each enzyme in either cell line. This finding suggests that the type or nature of the cutting sequence itself may play a role in restriction enzyme-induced cell killing. 32 refs., 6 figs., 3 tabs

  13. Protein covalent immobilization via its scarce thiol versus abundant amine groups: Effect on orientation, cell binding domain exposure and conformational lability.

    Science.gov (United States)

    Ba, O M; Hindie, M; Marmey, P; Gallet, O; Anselme, K; Ponche, A; Duncan, A C

    2015-10-01

    Quantity, orientation, conformation and covalent linkage of naturally cell adhesive proteins adsorbed or covalently linked to a surface, are known to influence the preservation of their subsequent long term cell adhesion properties and bioactivity. In the present work, we explore two different strategies for the covalent linking of plasma fibronectin (pFN) - used as a cell adhesive model protein, onto a polystyrene (PS) surface. One is aimed at tethering the protein to the surface in a semi-oriented fashion (via one of the 4 free thiol reactive groups on the protein) with a heterofunctional coupling agent (SSMPB method). The other aims to immobilize the protein in a more random fashion by reaction between the abundant pendant primary amine bearing amino acids of the pFN and activated carboxylic surface functions obtained after glutaric anhydride surface treatment (GA method). The overall goal will be to verify the hypothesis of a correlation between covalent immobilization of a model cell adhesive protein to a PS surface in a semi-oriented configuration (versus randomly oriented) with promotion of enhanced exposure of the protein's cell binding domain. This in turn would lead to enhanced cell adhesion. Ideally the goal is to elaborate substrates exhibiting a long term stable protein monolayer with preserved cell adhesive properties and bioactivity for biomaterial and/or cell adhesion commercial plate applications. However, the initial restrictive objective of this paper is to first quantitatively and qualitatively investigate the reversibly (merely adsorbed) versus covalently irreversibly bound protein to the surface after the immobilization procedure. Although immobilized surface amounts were similar (close to the monolayer range) for all immobilization approaches, covalent grafting showed improved retention and stronger "tethering" of the pFN protein to the surface (roughly 40%) after SDS rinsing compared to that for mere adsorption (0%) suggesting an added value

  14. Comparison of DNA double-strand break rejoining as measured by pulsed field gel electrophoresis, neutral sucrose gradient centrifugation and non-unwinding filter elution in irradiated plateau-phase CHO cells

    International Nuclear Information System (INIS)

    Iliakis, G.; Metzger, L.; Pantelias, G.

    1991-01-01

    The initial (up to 30 min) rate of DNA double-strand break (dsb) rejoining was measured in irradiated plateau-phase CHO cells, in a set of parallel experiments using the same cell suspension, by means of non-unwinding filter elution, neutral sucrose gradient centrifugation, and two pulsed-field gel electrophoresis assays: asymmetric field inversion gel electrophoresis (AFIGE) and clamped homogeneous electric field (CHEF) gel electrophoresis. The rate of DNA dsb rejoining was compared to the rate of rejoining of chromatin breaks measured, also in the same cell population, using the technique of premature chromosome condensation (PCC). Two radiation exposures, 25 Gy and/or 50 Gy, were used and applied to the individual parts of the experiments according to the sensitivity of the assay under investigation. The results suggest all major techniques currently used for assaying rejoining of DNA dsb give similar results, and indicate that more information is required before a direct correlation between rejoining of DNA dsb and rejoining of chromatin breaks can be established. (author)

  15. Two schemes for production of biosurfactant from Pseudomonas aeruginosa MR01: Applying residues from soybean oil industry and silica sol-gel immobilized cells.

    Science.gov (United States)

    Bagheri Lotfabad, Tayebe; Ebadipour, Negisa; Roostaazad, Reza; Partovi, Maryam; Bahmaei, Manochehr

    2017-04-01

    Rhamnolipids are the most common biosurfactants and P. aeruginosa strains are the most frequently studied microorganisms for the production of rhamnolipids. Eco-friendly advantages and promising applications of rhamnolipids in various industries are the major reasons for pursuing the economic production of these biosurfactants. This study shows that cultivation of P. aeruginosa MR01 in medium contained inexpensive soybean oil refinery wastes which exhibited similar levels and homologues of rhamnolipids. Mass spectrometry indicated that the Rha-C10-C10 and Rha-Rha-C10-C10 constitute the main rhamnolipids in different cultures of MR01 including one of oil carbon source analogues. Moreover, rhamnolipid mixtures extracted from different cultures showed critical micelle concentrations (CMC) in the range of ≃24 to ≃36mg/l with capability to reduce the surface tension of aqueous solution from 72 to ≃27-32mN/m. However, the sol-gel technique using tetraethyl orthosilicate (TEOS) was used as a gentler method in order to entrap the P. aeruginosa MR01 cells in mold silica gels. Immobilized cells can be utilized several times in consecutive fermentation batches as well as in flow fermentation processes. In this way, reusability of the cells may lead to a more economical fermentation process. Approximately 90% of cell viability was retained during the silica sol-gel immobilization and ≃84% of viability of immobilized cells was preserved for 365days of immobilization and storage of the cells in phosphate buffer at 4°C and 25°C. Moreover, mold gels showed good mechanical stability during the seven successive fermentation batches and the entrapped cells were able to efficiently preserve their biosurfactant-producing potential. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Fluctuation correlation models for receptor immobilization

    Science.gov (United States)

    Fourcade, B.

    2017-12-01

    Nanoscale dynamics with cycles of receptor diffusion and immobilization by cell-external-or-internal factors is a key process in living cell adhesion phenomena at the origin of a plethora of signal transduction pathways. Motivated by modern correlation microscopy approaches, the receptor correlation functions in physical models based on diffusion-influenced reaction is studied. Using analytical and stochastic modeling, this paper focuses on the hybrid regime where diffusion and reaction are not truly separable. The time receptor autocorrelation functions are shown to be indexed by different time scales and their asymptotic expansions are given. Stochastic simulations show that this analysis can be extended to situations with a small number of molecules. It is also demonstrated that this analysis applies when receptor immobilization is coupled to environmental noise.

  17. IMMOBILIZATION OF MICROALGAE ON THE SURFACE OF NEW CROSS-LINKED POLYETHYLENIMINE-BASED SORBENTS.

    Science.gov (United States)

    Vasilieva, Svetlana; Shibzukhova, Karina; Morozov, Alexey; Solovchenko, Alexei; Bessonov, Ivan; Kopitsyna, Maria; Lukyanov, Alexander; Chekanov, Konstantin; Lobakova, Elena

    2018-04-11

    We report on the use of the polyethylenimine-based (PEI) sorbents for immobilization and harvesting of microalgae (MA) cells. Specific materials assessed were porous solid polymers from highly-branched PEI synthesized by cross-linking with epichlorohydrin (ECH) or diethylene glycol diglycidyl ether (DGDE). We estimated the effect of PEI/cross-linker ratio on the MA attachment and biocompatibility of the sorbents with the MA cells. A decrease in the cross-linker percentage resulted in the enhancement of the immobilization efficiency but impaired the cell viability as was manifested by inhibition of the photosynthetic activity of the MA cells. The rate of Chlorella vulgaris cell attachment to the sorbents with ECH was faster as compared to that of the PEI-DGDE-based polymers. The cells immobilized on the PEI-ECH sorbents showed a more profound decline in their viability (assessed via photosynthetic activity). The sorbents with 60% of DGDE were characterized by high immobilization efficiency. These sorbents supported a prolonged cultivation of the immobilized MA without impairing their viability and metabolic activity. We conclude that the sorbents with a lower percentage of DGDE (<30%) and sorbents with ECH are suitable for harvesting of the MA cells intended for immediate downstream processing, potentially without the cell desorption. To the best of our knowledge, this is the first report on successful application of PEI-based sorbents in microalgal biotechnology. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Production of Biodiesel Using Immobilized Lipase and the Characterization of Different Co-Immobilizing Agents and Immobilization Methods

    Directory of Open Access Journals (Sweden)

    Kang Zhao

    2016-08-01

    Full Text Available Lipase from Candida sp. 99–125 is widely employed to catalyzed transesterification and can be used for biodiesel production. In this study, the lipase was immobilized by combined adsorption and entrapment to catalyze biodiesel production from waste cooking oil (WCO via transesterification, and investigating co-immobilizing agents as additives according to the enzyme activity. The addition of the mixed co-immobilizing agents has positive effects on the activities of the immobilized lipase. Three different immobilizing methods were compared by the conversion ratio of biodiesel and structured by Atom Force Microscopy (AFM and Scanning Electron Microscopy (SEM, respectively. It was found that entrapment followed by adsorption was the best method. The effect of the co-immobilizing agent amount, lipase dosage, water content, and reuse ability of the immobilized lipase was investigated. By comparison with previous research, this immobilized lipase showed good reuse ability: the conversion ratio excesses 70% after 10 subsequent reactions, in particular, was better than Novozym435 and TLIM on waste cooking oil for one unit of lipase.

  19. A novel multistep method for chondroitin sulphate immobilization and its interaction with fibroblast cells

    Energy Technology Data Exchange (ETDEWEB)

    Ozaltin, Kadir; Lehocký, Marián, E-mail: lehocky@post.cz; Kuceková, Zdenka; Humpolíček, Petr; Sáha, Petr

    2017-01-01

    Polymeric biomaterials are widely used in medical applications owing to their low cost, processability and sufficient toughness. Surface modification by creating a thin film of bioactive agents is promising technique to enhance cellular interactions, regulate the protein adsorption and/or avoid bacterial infections. Polyethylene is one of the most used polymeric biomaterial but its hydrophobic nature impedes its further chemical modifications. Plasma treatment is unique method to increase its hydrophilicity by incorporating hydrophilic oxidative functional groups and tailoring the surface by physical etching. Furthermore, grafting of polymer brushes of amine group containing monomers onto the functionalized surface lead to strongly immobilized bioactive agents at the final step. Chondroitin sulphate is natural polysaccharide mainly found in connective cartilage tissue which used as a bioactive agent to immobilize onto polyethylene surface by multistep method in this study. - Highlights: • Attachment of chondroitin sulfate to polyethylene. • A robust way to modify surfaces using multistep approach. • The modified surfaces showed improved proliferation of mouse primary fibroblast cells.

  20. Radiation technology for immobilization of bioactive materials

    International Nuclear Information System (INIS)

    1988-12-01

    Within the framework of the Agency's coordinated research programme on ''Application of Radiation Technology in Immobilization of Bioactive Materials'', the third and final research coordination meeting was held at Beijing University, Beijing, People's Republic of China, 15-18 June 1987. The present publication compiles all presentations made at the meeting. Fundamental processes for the immobilization of enzymes, antibodies, cells and drugs were developed and established using gamma radiation, electron beams and plasma discharge. Applications of various biofunctional components, immobilized by radiation techniques in different processes, were studied. A range of backbone polymers has been examined together with various monomers. Coupling procedures have been developed which are relevant to our particular requirements. Enzymes of various types and characteristics have been immobilized with considerable efficiency. The immobilized biocatalysts have been shown to possess significant activity and retention of activity on storage. There appears to be a high degree of specificity associated with the properties of the immobilised biocatalysts, their activity and the ease of their preparation. Novel additives which lower the total radiation dose in grafting have been discovered and their value in immobilization processes assessed. Potential applications include: medical (diagnostic, therapeutic), and industrial processes (fermentation, bioseparation, etc.). Refs, figs and tabs

  1. Antimicrobial and cell viability measurement of bovine serum albumin capped silver nanoparticles (Ag/BSA) loaded collagen immobilized poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) film.

    Science.gov (United States)

    Bakare, Rotimi; Hawthrone, Samantha; Vails, Carmen; Gugssa, Ayele; Karim, Alamgir; Stubbs, John; Raghavan, Dharmaraj

    2016-03-01

    Bacterial infection of orthopedic devices has been a major concern in joint replacement procedures. Therefore, this study is aimed at formulating collagen immobilized poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) film loaded with bovine serum albumin capped silver nanoparticles (Ag/BSA NPs) to inhibit bacterial growth while retaining/promoting osteoblast cells viability. The nanoparticles loaded collagen immobilized PHBV film was characterized for its composition by X-ray Photoelectron Spectroscopy and Anodic Stripping Voltammetry. The extent of loading of Ag/BSA NPs on collagen immobilized PHBV film was found to depend on the chemistry of the functionalized PHBV film and the concentration of Ag/BSA NPs solution used for loading nanoparticles. Our results showed that more Ag/BSA NPs were loaded on higher molecular weight collagen immobilized PHEMA-g-PHBV film. Maximum loading of Ag/BSA NPs on collagen immobilized PHBV film was observed when 16ppm solution was used for adsorption studies. Colony forming unit and optical density measurements showed broad antimicrobial activity towards Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa at significantly lower concentration i.e., 0.19 and 0.31μg/disc, compared to gentamicin and sulfamethoxazole trimethoprim while MTT assay showed that released nanoparticles from Ag/BSA NPs loaded collagen immobilized PHBV film has no impact on MCTC3-E1 cells viability. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Immobilization of Saccharomyces Cerevisiae in Rice Hulls for Ethanol Production

    Directory of Open Access Journals (Sweden)

    Edita Martini

    2011-05-01

    Full Text Available The whole cell immobilization in ethanol fermentation can be done by using natural carriers or through synthetic carriers. All of these methods have the same purpose of retaining high cell concentrations within a certain defined region of space which leads to higher ethanol productivity. Lignocellulosic plant substance represents one of highly potential sources in ethanol production. Some studies have found that cellulosic substances substances can also be used as a natural carrier in cell immobilization by re-circulating pre-culture medium into a reactor. In this experiment, rice hulls without any treatment were used to immobilize Saccharomyces cerevisiae through semi solid state incubation combined with re-circulating pre-culture medium. The scanning electron microscopy (SEM pictures of the carrier show that the yeast cells are absorbed and embedded to the rice hull pore. In liquid batch fermentation system with an initial sugar concentration of 50 g/L, nearly 100% total sugar was consumed after 48 hours. This resulted in an ethanol yield of 0.32 g ethanol/g glucose, which is 62.7% of the theoretical value. Ethanol productivity of 0.59 g/(L.h is 2.3 fold higher than that of free cells which is 0.26 g/(L.h. An effort to reuse the immobilized cells in liquid fermentation system showed poor results due to cell desorption in the first batch which led to high sugar concentration inhibitory effect in the second batch fermentation. This might be solved by using semi solid fermentation process in the future work.

  3. Production of isomaltulose obtained by Erwinia sp. cells submitted to different treatments and immobilized in calcium alginate

    Directory of Open Access Journals (Sweden)

    Haroldo Yukio Kawaguti

    2011-03-01

    Full Text Available In recent decades, there has been an increase in the studies of isomaltulose obtainment, due to its physicochemical properties and physiological health benefits. These properties, which include low cariogenicity, low glycemic index and greater stability, allow the use of this sweetener as a substitute for sucrose in foods; besides the fact that it can be converted to isomalt, a dietary non-cariogenic sugar alcohol used in pharmaceuticals as well as in the food industry. Isomaltulose (6-O-α-D-glucopyronosyl-1-6-D-fructofuranose is a disaccharide reducer obtained by the enzymatic conversion of sucrose - the α-glucosyltransferase enzyme. Different treatments were performed for the preparation of whole cells; lysed cells; and crude enzyme extract of Erwinia sp. D12 strain immobilized in calcium alginate. The packed bed column of granules, containing Erwinia sp. cells sonicated and immobilized in calcium alginate (CSI, reached a maximum conversion of 53-59% sucrose into isomaltulose and it presented activity for 480 hours. The converted syrup was purified and the isomaltulose crystallization was performed through the lowering of temperature. The isomaltulose crystals presented purity of 96.5%.

  4. Catalytical Properties of Free and Immobilized Aspergillus niger Tannase

    Directory of Open Access Journals (Sweden)

    Abril Flores-Maltos

    2011-01-01

    Full Text Available A fungal tannase was produced, recovered, and immobilized by entrapment in calcium alginate beads. Catalytical properties of the immobilized enzyme were compared with those of the free one. Tannase was produced intracellularly by the xerophilic fungus Aspergillus niger GH1 in a submerged fermentation system. Enzyme was recovered by cell disruption and the crude extract was partially purified. The catalytical properties of free and immobilized tannase were evaluated using tannic acid and methyl gallate as substrates. KM and Vmax values for free enzyme were very similar for both substrates. But, after immobilization, KM and Vmax values increased drastically using tannic acid as substrate. These results indicated that immobilized tannase is a better biocatalyst than free enzyme for applications on liquid systems with high tannin content, such as bioremediation of tannery or olive-mill wastewater.

  5. Catalytical Properties of Free and Immobilized Aspergillus niger Tannase.

    Science.gov (United States)

    Flores-Maltos, Abril; Rodríguez-Durán, Luis V; Renovato, Jacqueline; Contreras, Juan C; Rodríguez, Raúl; Aguilar, Cristóbal N

    2011-01-01

    A fungal tannase was produced, recovered, and immobilized by entrapment in calcium alginate beads. Catalytical properties of the immobilized enzyme were compared with those of the free one. Tannase was produced intracellularly by the xerophilic fungus Aspergillus niger GH1 in a submerged fermentation system. Enzyme was recovered by cell disruption and the crude extract was partially purified. The catalytical properties of free and immobilized tannase were evaluated using tannic acid and methyl gallate as substrates. K(M) and V(max) values for free enzyme were very similar for both substrates. But, after immobilization, K(M) and V(max) values increased drastically using tannic acid as substrate. These results indicated that immobilized tannase is a better biocatalyst than free enzyme for applications on liquid systems with high tannin content, such as bioremediation of tannery or olive-mill wastewater.

  6. Performance of the ACWA Pilot Immobilized Cell Bioreactor in Degradation of HD and Tetrytol Payloads of the M60 Chemical Round

    National Research Council Canada - National Science Library

    Guelta, Mark A; Chester, Nancy A; Kurnas, Carl W; Haley, Mark V; Lupton, F. S; Koch, Mark

    2002-01-01

    .... Neutralization followed by biodegradation was one technology identified as having potential. Guelta and DeFrank conducted preliminary laboratory studies using 1-liter Immobilized Cell Bioreactors (ICB...

  7. Rapid detection of food pathogens using RNA aptamers-immobilized slide.

    Science.gov (United States)

    Maeng, Jin-Soo; Kim, Namsoo; Kim, Chong-Tai; Han, Seung Ryul; Lee, Young Ju; Lee, Seong-Wook; Lee, Myung-Hyun; Cho, Yong-Jin

    2012-07-01

    The purpose of this study was to develop a simple and rapid detection system for foodborne bacteria, which consisted of an optical microscope and its slide chip with artificial antibodies, or RNA aptamers. From an RNA pool, three each RNA aptamers were built by the method of SELEX (systematic evolution of ligands by exponential enrichment) for components of cell wall, LPS (lipopolysaccharide) from E. coli O157:H7, teichoic acid from Staphylococcus aureus and a cell membrane protein of OmpC from Salmonella typhimurium, respectively. These aptamers were hybridized with thiol-conjugated 16 dT-linker molecules in order to be immobilized on silver surface which was, in advance, fabricated on glass slide, using a spin-coating method. To confirm that each aptamers retained its specific binding activities to their antigenic live bacteria, microscopic view of bound cells immobilized on silver film were observed. Furthermore, we observed the fluorescence-emitting bacteria-aptamer complex immobilized on silver film after adding RNA aptamers hybridized with fluorophore, FAM-conjugated 16 dT-linker molecules. As a result, the RNA aptamers-immobilized slide system developed in this study was a useful new tool to rapidly monitor individual food pathogens.

  8. Hierarchically Nanoporous Bioactive Glasses for High Efficiency Immobilization of Enzymes

    DEFF Research Database (Denmark)

    He, W.; Min, D.D.; Zhang, X.D.

    2014-01-01

    Bioactive glasses with hierarchical nanoporosity and structures have been heavily involved in immobilization of enzymes. Because of meticulous design and ingenious hierarchical nanostructuration of porosities from yeast cell biotemplates, hierarchically nanostructured porous bioactive glasses can...... and products of catalytic reactions can freely diffuse through open mesopores (2–40 nm). The formation mechanism of hierarchically structured porous bioactive glasses, the immobilization mechanism of enzyme and the catalysis mechanism of immobilized enzyme are then discussed. The novel nanostructure...

  9. Surface engineering of Ti-O films by photochemical immobilization of gelatin

    International Nuclear Information System (INIS)

    Weng, Y.J.; Ren, J.R.; Huang, N.; Wang, J.; Chen, J.Y.; Leng, Y.X.; Liu, H.Q.

    2008-01-01

    Crystalline Ti-O films were prepared by unbalanced magnetron sputtering and the structure was confirmed by XRD. An organic layer of 3-aminopropylphosphonic acid (APP) was first introduced on the Ti-O films by self-assembling. The stability of the APP on Ti-O films was confirmed by XPS and FTIR analysis. Simultaneously, azido group was introduced in gelatin molecule to act as photoreactive point. The derivated gelatin was spin-coated onto the self-assembled layer and immobilized by UV irradiating. Chemical patterned surface was obtained by using a photomask when irradiating and confirmed by sirius red staining and surface profile analysis. Measured by surface profilometer, the thickness of the immobilized gelatin was about 5-20 nm. The adhering of human endothelial EVC304 cells on APP modified surface was enhanced in the cell culture test. Moreover, the adherence and growth of cells were prior on gelatin-immobilized region visually seen on the patterned surface. This result indicated gelatin-immobilized Ti-O surface can serve as a biocompatible biomaterial for endothelialization

  10. Production of D-tagatose at high temperatures using immobilized Escherichia coli cells expressing L-arabinose isomerase from Thermotoga neapolitana.

    Science.gov (United States)

    Hong, Young-Ho; Lee, Dong-Woo; Lee, Sang-Jae; Choe, Eun-Ah; Kim, Seong-Bo; Lee, Yoon-Hee; Cheigh, Chan-Ick; Pyun, Yu-Ryang

    2007-04-01

    Escherichia coli cells expressing L-arabinose isomerase from Thermotoga neapolitana (TNAI) were immobilized in calcium alginate beads. The resulting cell reactor (2.4 U, t (1/2) = 43 days at 70 degrees C) in a continuous recycling mode at 70 degrees C produced 49 and 38 g D-tagatose/l from 180 and 90 g D-galactose/l, respectively, within 12 h.

  11. Microchip analysis of lithium in blood using moving boundary electrophoresis and zone electrophoresis

    NARCIS (Netherlands)

    Vrouwe, E.X.; Lüttge, Regina; Olthuis, Wouter; van den Berg, Albert

    The determination of inorganic cations in blood plasma is demonstrated using a combination of moving boundary electrophoresis (MBE) and zone electrophoresis. The sample loading performed under MBE conditions is studied with the focus on the quantitative analysis of lithium. A concentration

  12. Microchip analysis of lithium in blood using moving boundary electrophoresis and zone electrophoresis

    NARCIS (Netherlands)

    Vrouwe, E.X.; Luttge, R.; Olthuis, W.; Berg, van den A.

    2005-01-01

    The determination of inorganic cations in blood plasma is demonstrated using a combination of moving boundary electrophoresis (MBE) and zone electrophoresis. The sample loading performed under MBE conditions is studied with the focus on the quantitative analysis of lithium. A concentration

  13. Capillary electrophoresis microchip coupled with on-line chemiluminescence detection

    International Nuclear Information System (INIS)

    Su Rongguo; Lin Jinming; Qu Feng; Chen Zhifeng; Gao Yunhua; Yamada, Masaaki

    2004-01-01

    In the present work, chemiluminescence detection was integrated with capillary electrophoresis microchip. The microchip was designed on the principle of flow-injection chemiluminescence system and capillary electrophoresis. It has three main channels, five reservoirs and a detection cell. As model samples, dopamine and catechol were separated and detected using a permanganate chemiluminescent system on the prepared microchip. The samples were electrokinetically injected into the double-T cross section, separated in the separation channel, and then oxidized by chemiluminescent reagent delivered by a home-made micropump to produce light in the detection cell. The electroosmotic flow could be smoothly coupled with the micropump flow. The detection limits for dopamine and catechol were 20.0 and 10.0 μM, respectively. Successful separation and detection of dopamine and catechol demonstrated the distinct advantages of integration of chemiluminescent detection on a microchip for rapid and sensitive analysis

  14. Immobilization of cross linked Col-I–OPN bone matrix protein on aminolysed PCL surfaces enhances initial biocompatibility of human adipogenic mesenchymal stem cells (hADMSC)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young-Hee; Jyoti, Md. Anirban; Song, Ho-Yeon, E-mail: songmic@sch.ac.kr

    2014-06-01

    In bone tissue engineering surface modification is considered as one of the important ways of fabricating successful biocompatible material. Addition of biologically active functionality on the surfaces has been tried for improving the overall biocompatibility of the system. In this study poly-ε-caprolactone film surfaces have been modified through aminolysis and immobilization process. Collagen type I (COL-I) and osteopontin (OPN), which play an important role in osteogenesis, was immobilized onto PCL films followed by aminolysis treatment using 1,6-hexanediamine. Characterization of animolysed and immobilized surfaces were done by a number techniques using scanning electron microscopy (SEM), FT-IR, XPS, ninhydrin staining, SDS-PAGE and confocal microscopy and compared between the modified and un-modified surfaces. Results of the successive experiments showed that aminolysis treatment was homogeneously achieved which helped to entrap or immobilize Col-I–OPN proteins on surfaces of PCL film. In vitro studies with human adipogenic mesenchymal stem cells (hADMSC) also confirmed the attachment and proliferation of cells was better in modified PCL surfaces than the unmodified surfaces. SEM, confocal microscopy and MTT assay showed a significant increase in cell spreading, attachment and proliferations on the biofunctionalized surfaces compared to the unmodified PCL surfaces at all-time points indicating the success of surface biofunctionalization.

  15. Arginine-assisted immobilization of silver nanoparticles on ZnO nanorods: an enhanced and reusable antibacterial substrate without human cell cytotoxicity

    Science.gov (United States)

    Agnihotri, Shekhar; Bajaj, Geetika; Mukherji, Suparna; Mukherji, Soumyo

    2015-04-01

    Silver-based hybrid nanomaterials are gaining interest as potential alternatives for conventional antimicrobial agents. Herein, we present a simple, facile and eco-friendly approach for the deposition of silver nanoparticles (AgNPs) on ZnO nanorods, which act as a nanoreactor for in situ synthesis and as an immobilizing template in the presence of arginine. The presence of arginine enhanced the stability of ZnO deposition on the glass substrate by hindering the dissolution of zinc under alkaline conditions. Various Ag/ZnO hybrid nanorod (HNR) samples were screened to obtain a high amount of silver immobilization on the ZnO substrate. Ag/ZnO HNRs displayed potent antibacterial ability and could achieve 100% kill for both Escherichia coli and Bacillus subtilis strains under various test conditions. The hybrid material mediated its dual mode of antibacterial action through direct contact-killing and release of silver ions/nanoparticles and showed superior bactericidal performance compared to pure ZnO nanorods and colloidal AgNPs. No significant decline in antibacterial efficacy was observed even after the same substrate was repeatedly reused multiple times. Interestingly, the amount of Ag and Zn release was much below their maximal limit in drinking water, thus preventing potential health hazards. Immobilized AgNPs showed no cytotoxic effects on the human hepatocarcinoma cell line (HepG2). Moreover, treating cells with the antibacterial substrate for 24 hours did not lead to significant generation of reactive oxygen species (ROS). The good biocompatibility and bactericidal efficacy would thus make it feasible to utilize this immobilization strategy for preparing new-generation antibacterial coatings.Silver-based hybrid nanomaterials are gaining interest as potential alternatives for conventional antimicrobial agents. Herein, we present a simple, facile and eco-friendly approach for the deposition of silver nanoparticles (AgNPs) on ZnO nanorods, which act as a

  16. AFM imaging of bacteria in liquid media immobilized on gelatin coated mica surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Doktycz, M.J.; Sullivan, C.J.; Hoyt, P.R.; Pelletier, D.A.; Wu, S.; Allison, D.P

    2003-10-15

    Immobilization of particulates, especially biomolecules and cells, onto surfaces is critical for imaging with the atomic force microscope (AFM). In this paper, gelatin coated mica surfaces are shown to be suitable for immobilizing and imaging both gram positive, Staphylococcus aureus, and gram negative, Escherichia coli, bacteria in both air and liquid environments. Gelatin coated surfaces are shown to be superior to poly-L-lysine coated surfaces that are commonly used for the immobilization of cells. This cell immobilization technique is being developed primarily for live cell imaging of Rhodopseudomonas palustris. The genome of R. palustris has been sequenced and the organism is the target of intensive studies aimed at understanding genome function. Images of R. palustris grown both aerobically and anaerobically in liquid media are presented. Images in liquid media show the bacteria is rod shaped and smooth while images in air show marked irregularity and folding of the surface. Significant differences in the vertical dimension are also apparent with the height of the bacteria in liquid being substantially greater than images taken in air. In air immobilized bacterial flagella are clearly seen while in liquid this structure is not visible. Additionally, significant morphological differences are observed that depend on the method of bacterial growth.

  17. Immobilization of calcium and phosphate ions improves the osteoconductivity of titanium implants

    International Nuclear Information System (INIS)

    Sunarso; Toita, Riki; Tsuru, Kanji; Ishikawa, Kunio

    2016-01-01

    In this work, to elevate weak osteoconductivity of titanium (Ti) implant, we prepared a Ti implant having both calcium and phosphate ions on its surface. To modify calcium and phosphate ions onto Ti, phosphate ions were first immobilized by treating the Ti with a NaH 2 PO 4 solution, followed by CaCl 2 treatment to immobilize calcium ions, which created the calcium and phosphate ions-modified Ti (Ca-P-Ti). X-ray photoelectron spectroscopy and thin-layer X-ray diffraction measurement confirmed that both phosphate and calcium ions were co-immobilized onto the Ti surface on the molecular level. Three-hour after seeding MC3T3-E1 murine pre-osteoblast cells on substrates, cell number on Ca-P-Ti was much larger than that of Ti and phosphate-modified Ti (P-Ti), but was similar to that of calcium-modified Ti (Ca-Ti). Also, MC3T3-E1 cells on Ca-P-Ti expressed larger amount of vinculin, a focal adhesion protein, than those on other substrates, probably resulting in larger cell size as well as greater cell proliferation on Ca-P-Ti than those on other substrates. Alkaline phosphatase activity of cells on Ca-P-Ti was greater than those on Ti and P-Ti, but was almost comparable to that of Ca-Ti. Moreover, the largest amount of bone-like nodule formation was observed on Ca-P-Ti. These results provide evidence that calcium and phosphate ions-co-immobilization onto Ti increased the osteoconductivity of Ti by stimulating the responses of pre-osteoblast cells. This simple modification would be promising technique for bone tissue implant including dental and orthopedic implants. - Highlights: • Phosphate and calcium ions have been successfully co-immobilize on Ti surface. • Co-immobilization of Ca and phosphate ions (Ca-P-Ti) did not alter the original surface morphology. • Ca-P-Ti significantly improved initial MC3T3-E1 cell adhesion. • Ca-P-Ti demonstrated remarkable cell proliferation, differentiation and mineralization. • Overall, Ca-P-Ti would be a promising bone

  18. Isomaltulose production using free and immobilized Serratia ...

    African Journals Online (AJOL)

    Isomaltulose is a low cariogenic sweetener used as a substitute for sucrose in the food industry. In this study, isomaltulose production by Serratia plymuthica ATCC 15928 was performed using free and immobilized cells. Response Surface Methodology was employed to evaluate the influence of temperature, wet cell mass ...

  19. Usage of Capillary Electrophoresis for screening common Hemoglobinopathies

    Directory of Open Access Journals (Sweden)

    2016-06-01

    Full Text Available Hemoglobinopathies are most common inherited disorders in the world approximately 7 percent of the worldwide population and 5-6 percent of population of Iran are carriers. For control of this inherited hemoglobin disorders need to accurate screening by more advanced and more accurate methods. This study explains features of current Iran hemoglobin disorders, nominates the accessible methods for screening them and introduces the capillary zone electrophoresis as a rapid & more accurate method. The required data were extracted of various articles and then for good explanation, current Iran hemoglobinopathies properties were showed in the tables and electropherograms of important hemoglobin disorders in Iran population were provided for help to interpretation results of blood tests by capillary zone electrophoresis method. Hemoglobin disorders are including thalassemias & hemoglobin variants Disruption in the production and malfunction of globin chains cause types of hemoglobin disorders. We cannot introduce one of clinical laboratory tests as critical and basic method for screening and distinguishing types of inherited hemoglobin disorders as alone. For distinguishing the types of them must be prepared enough information and data of the hemoglobin disorders and for more accurate analysis must be used simultaneously different methods as Gel electrophoresis, High performance liquid chromatography, Isoelectric focusing, Capillary zone electrophoresis or molecular tests. The capillary electrophoresis is an accurate and rapid method for screening types of the hemoglobin disorders. Other side this method cannot analyze all of them, so must be used biochemical, biophysical and molecular methods for confirmation the results. This review showed we can use the capillary electrophoresis and HPLC as two complementary methods for hemoglobinopathies screening. We can analyze by the methods more hemoglobin disorders and decrease more laboratory errors. Moreover

  20. MUCOADHESIVE GEL WITH IMMOBILIZED LYSOZYME: PREPARATION AND PROPERTIES

    Directory of Open Access Journals (Sweden)

    Dekina S. S.

    2015-08-01

    Full Text Available The study of non-covalent immobilized lysozyme, as well as physico-chemical and biochemical properties of obtained mucoadhesive gel was the aim of the research. Lysozyme activity was determined by bacteriolytic method (Micrococcus lysodeikticus cells acetone powder was a substrate. Lysozyme immobilization was conducted by the method of entrapment in gel. Enzyme carrier interaction was studied by viscometric, spectrophotometric and spectrofluorimetric methods. Mucoadhesive gel with immobilized lysozyme, possessing antiinflammatory and antimicrobial activities, was prepared. Due to immobilization, protein-polymer complex with the original enzymatic activity was formed. The product is characterized by high mucoadhesive properties, quantitative retaining of protein and bacteriolytic activity, prolonged release of the enzyme, improved biochemical characteristics (extended pH-activity profile, stability in acidic medium and during storage for 2 years, and it is perspective for further studies. The proposed method for lysozyme immobilization in the carboxymethyl cellulose sodium salt gel allows to obtain a stable, highly efficient product, with high adhesive properties for attachment to the mucous membranes, that is promising for use in biomedicine.

  1. Citric acid production from partly deproteinized whey under non-sterile culture conditions using immobilized cells of lactose-positive and cold-adapted Yarrowia lipolytica B9.

    Science.gov (United States)

    Arslan, Nazli Pinar; Aydogan, Mehmet Nuri; Taskin, Mesut

    2016-08-10

    The present study was performed to produce citric acid (CA) from partly deproteinized cheese whey (DPCW) under non-sterile culture conditions using immobilized cells of the cold-adapted and lactose-positive yeast Yarrowia lipolytica B9. DPCW was prepared using the temperature treatment of 90°C for 15min. Sodium alginate was used as entrapping agent for cell immobilization. Optimum conditions for the maximum CA production (33.3g/L) in non-sterile DPCW medium were the temperature of 20°C, pH 5.5, additional lactose concentration of 20g/L, sodium alginate concentration of 2%, number of 150 beads/100mL and incubation time of 120h. Similarly, maximum citric acid/isocitric acid (CA/ICA) ratio (6.79) could be reached under these optimal conditions. Additional nitrogen and phosphorus sources decreased CA concentration and CA/ICA ratio. Immobilized cells were reused in three continuous reaction cycles without any loss in the maximum CA concentration. The unique combination of low pH and temperature values as well as cell immobilization procedure could prevent undesired microbial contaminants during CA production. This is the first work on CA production by cold-adapted microorganisms under non-sterile culture conditions. Besides, CA production using a lactose-positive strain of the yeast Y. lipolytica was investigated for the first time in the present study. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Study on dose-effect relationship of radiation-induced DNA damage using single cell gel electrophoresis

    International Nuclear Information System (INIS)

    Liu Qiang; Jiang Enhai; Li Jin; Tang Weisheng; Wang Zhiquan; Zhao Yongcheng; Fan Feiyue

    2006-01-01

    Objective: To explore a new, simple and quick radiation biodosimeter, which can be applied to estimate biological dose in case of radiation accident. Methods: DNA double-strand break were detected using neutral single cell gel electrophoresis (SCGE), and all the indexes of comet assay including HDNA%, TDNA%, CL, TL, TM, and OTM were analyzed by CASP (Comet Assay Software Project). The curve of dose-effect was fitted using SPSS 12.0 software. Results: Statistically significant dose-effect relationships were observed in all the indexes of comet assay, OTM was superior to other indexes. Conclusions: Application of neutral comet assay combined with CASP analysis could serve as a new radiation biodosimeter. (authors)

  3. Nickel foam-supported polyaniline cathode prepared with electrophoresis for improvement of rechargeable Zn battery performance

    Science.gov (United States)

    Xia, Yang; Zhu, Derong; Si, Shihui; Li, Degeng; Wu, Sen

    2015-06-01

    Porous nickel foam is used as a substrate for the development of rechargeable zinc//polyaniline battery, and the cathode electrophoresis of PANI microparticles in non-aqueous solution is applied to the fabrication of Ni foam supported PANI electrode, in which the corrosion of the nickel foam substrate is prohibited. The Ni foam supported PANI cathode with high loading is prepared by PANI electrophoretic deposition, and followed by PANI slurry casting under vacuum filtration. The electrochemical charge storage performance for PANI material is significantly improved by using nickel foam substrate via the electrophoretic interlayer. The specific capacity of the nickel foam-PANI electrode with the electrophoretic layer is higher than the composite electrode without the electrophoretic layer, and the specific capacity of PANI supported by Ni foam reaches up to 183.28 mAh g-1 at the working current of 2.5 mA cm-2. The present electrophoresis deposition method plays the facile procedure for the immobilization of PANI microparticles onto the surface of non-platinum metals, and it becomes feasible to the use of the Ni foam supported PANI composite cathode for the Zn/PANI battery in weak acidic electrolyte.

  4. Degradation of methyl tert-butyl ether by gel immobilized Methylibium petroleiphilum PM1.

    Science.gov (United States)

    Chen, Dongzhi; Chen, Jianmeng; Zhong, Weihong; Cheng, Zhuowei

    2008-07-01

    Cells of Methylibium petroleiphilum PM1 were immobilized in gel beads to degrade methyl tert-butyl ether (MTBE). Calcium alginate, agar, polyacrylamide and polyvinvyl alcohol were screened as suitable immobilization matrices, with calcium alginate demonstrating the fastest MTBE-degradation rate. The rate was accelerated by 1.8-fold when the beads had been treated in physiological saline for 24h at 28 degrees C. MTBE degradation in mineral salts medium (MSM) was accompanied by the increase of biomass. The half-life of MTBE-degradation activity for the encapsulated cells stored at 28 degrees C was about 120 h, which was obviously longer than that of free cells (approximately 36 h). Efficient reusability of the beads up to 30 batches was achieved in poor nutrition solution as compared to only 6 batches in MSM. The immobilized cells could be operated in a packed-bed reactor for degradation of 10 mg L(-1) MTBE in groundwater with more than 99% removal efficiency at hydraulic retention time of 20 min. These results suggested that immobilized cells of PM1 in bioreactor might be applicable to a groundwater treatment system for the removal of MTBE.

  5. EFFECTS OF IMMOBILIZATION IN Ba-ALGINATE ON NITRILE-DEPENDENT OXYGEN UPTAKE RATES OF CANDIDA GUILLIERMONDII

    Directory of Open Access Journals (Sweden)

    Dias João Carlos Teixeira

    2001-01-01

    Full Text Available Yeast cells immobilized by entrapment in Ba-alginate gel were investigated for growth pattern and respiratory activity. The oxygen uptake rates (OUR of cells entrapped in gels with 4% alginate were 5.2 and 23% lower than the OUR of 2% alginate and free cells, respectively. The mass-transfer resistance offered by the matrix and growth of the entrapped cells determine a gradient of nutrients throughout the gel which is responsible for both a lower specific growth rate of immobilized cells with respect to that of free ones, and a heterogeneous biomass distribution, with progressively increasing cellular density from the inside to the outside of the matrix. Gel-matrix polymer concentration affected the maximum oxygen uptake of immobilized growing yeast cells.

  6. Immobilization: A Revolution in Traditional Brewing

    Science.gov (United States)

    Virkajärvi, Ilkka; Linko, Matti

    In nature many micro-organisms tend to bind to solid surfaces. This tendency has long been utilized in a number of processes, for example in producing vinegar and acetic acid in bioreactors filled with wood shavings. Acetobacteria are attached to the surface of these shavings. In modern technical language: they are immobilized. Also yeast cells can be immobilized. In the brewing industry this has been the basis for maintaining efficient, continuous fermentation in bioreactors with very high yeast concentrations. The most dramatic change in brewing over recent years has been the replacement of traditional lagering of several weeks by a continuous process in which the residence time is only about 2h. Continuous primary fermentation is used on a commercial scale in New Zealand. In this process, instead of a carrier, yeast is retained in reactors by returning it partly after separation. In many pilot scale experiments the primary fermentation is shortened from about 1week to 1-2days using immobilized yeast reactors. When using certain genetically modified yeast strains no secondary fermentation is needed, and the total fermentation time in immobilized yeast reactors can therefore be shortened to only 2days.

  7. Vinegar Production from Jabuticaba (Myrciaria jaboticaba) Fruit Using Immobilized Acetic Acid Bacteria.

    Science.gov (United States)

    Dias, Disney Ribeiro; Silva, Monique Suela; Cristina de Souza, Angélica; Magalhăes-Guedes, Karina Teixeira; Ribeiro, Fernanda Severo de Rezende; Schwan, Rosane Freitas

    2016-09-01

    Cell immobilization comprises the retention of metabolically active cells inside a polymeric matrix. In this study, the production of jabuticaba ( Myrciaria jaboticaba ) vinegar using immobilized Acetobacter aceti and Gluconobacter oxydans cells is proposed as a new method to prevent losses of jabuticaba fruit surplus. The pulp of jabuticaba was processed and Saccharomyces cerevisiae CCMA 0200 was used to ferment the must for jabuticaba wine production. Sugars, alcohols (ethanol and glycerol) and organic acids were assayed by high-performance liquid chromatography. Volatile compounds were determined by gas chromatography-flame ionization detector. The ethanol content of the produced jabuticaba wine was approx. 74.8 g/L (9.5% by volume) after 168 h of fermentation. Acetic acid fermentation for vinegar production was performed using a mixed culture of immobilized A. aceti CCT 0190 and G. oxydans CCMA 0350 cells. The acetic acid yield was 74.4% and productivity was 0.29 g/(L·h). The vinegar had particularly high concentrations of citric (6.67 g/L), malic (7.02 g/L) and succinic (5.60 g/L) acids. These organic acids give a suitable taste and flavour to the vinegar. Seventeen compounds (aldehydes, higher alcohols, terpene, acetate, diether, furans, acids, ketones and ethyl esters) were identified in the jabuticaba vinegar. In conclusion, vinegar was successfully produced from jabuticaba fruits using yeast and immobilized mixed cultures of A. aceti and G. oxydans . To the best of our knowledge, this is the first study to use mixed culture of immobilized cells for the production of jabuticaba vinegar.

  8. Vinegar Production from Jabuticaba (Myrciaria jaboticaba Fruit Using Immobilized Acetic Acid Bacteria

    Directory of Open Access Journals (Sweden)

    Monique Suela Silva

    2016-01-01

    Full Text Available Cell immobilization comprises the retention of metabolically active cells inside a polymeric matrix. In this study, the production of jabuticaba (Myrciaria jaboticaba vinegar using immobilized Acetobacter aceti and Gluconobacter oxydans cells is proposed as a new method to prevent losses of jabuticaba fruit surplus. The pulp of jabuticaba was processed and Saccharomyces cerevisiae CCMA 0200 was used to ferment the must for jabuticaba wine production. Sugars, alcohols (ethanol and glycerol and organic acids were assayed by high-performance liquid chromatography. Volatile compounds were determined by gas chromatography-flame ionization detector. The ethanol content of the produced jabuticaba wine was approx. 74.8 g/L (9.5 % by volume after 168 h of fermentation. Acetic acid fermentation for vinegar production was performed using a mixed culture of immobilized A. aceti CCT 0190 and G. oxydans CCMA 0350 cells. The acetic acid yield was 74.4 % and productivity was 0.29 g/(L·h. The vinegar had particularly high concentrations of citric (6.67 g/L, malic (7.02 g/L and succinic (5.60 g/L acids. These organic acids give a suitable taste and flavour to the vinegar. Seventeen compounds (aldehydes, higher alcohols, terpene, acetate, diether, furans, acids, ketones and ethyl esters were identified in the jabuticaba vinegar. In conclusion, vinegar was successfully produced from jabuticaba fruits using yeast and immobilized mixed cultures of A. aceti and G. oxydans. To the best of our knowledge, this is the first study to use mixed culture of immobilized cells for the production of jabuticaba vinegar.

  9. Cultivation characteristics of immobilized Aspergillus oryzae for kojic acid production.

    Science.gov (United States)

    Kwak, M Y; Rhee, J S

    1992-04-15

    Aspergillus oryzae in situ grown from spores entrapped in calcium alginate gel beads was used for the production of kojic acid. The immobilized cells in flask cultures produced kojic acid in a linear proportion while maintaining the stable metabolic activity for a prolonged production period. Kojic acid was accumulated up to a high concentration of 83 g/L, at which the kojic acid began to crystallize, and, thus, the culture had to be replaced with fresh media for the next batch culture. The overall productivities of two consecutive cultivations were higher than that of free mycelial fermentation. However, the production rate of kojic acid by the immobilized cells was suddenly decreased with the appearance of central cavernae inside the immobilized gel beads after 12 days of the third batch cultivation.

  10. Radioprotective action on bone marrow CFU during immobilization of mice

    International Nuclear Information System (INIS)

    Keizer, H.J.; van Putten, L.M.

    1976-01-01

    Anesthesia and restraint without anesthesia during whole-body x-irradiation decrease the mortality from both the bone marrow and the intestinal syndromes (30- and 5-day mortality). The two types of immobilization decrease the radiosensitivity of the hemopoietic stem cells, as shown by an increased survival of hemopoietic stem cells in the marrow of immobilized mice. The hypoxic cell radiosensitizer Ro-07-0582 reversed the radioprotective effect during restraint without anesthesia, but not during pentobarbital anesthesia. This indicates that hypoxia of the femur bone marrow cannot explain the decreased radiosensitivity of the stem cells during pentobarbital anesthesia. Pentobarbital was also shown to inhibit the recruitment of resting femur bone marrow stem cells (G 0 -phase cells) into cycle following a sublethal dose of x rays. The relevance of these observations is discussed

  11. Bioremediation of Petrochemical Wastewater Containing BTEX Compounds by a New Immobilized Bacterium Comamonas sp. JB in Magnetic Gellan Gum.

    Science.gov (United States)

    Jiang, Bei; Zhou, Zunchun; Dong, Ying; Wang, Bai; Jiang, Jingwei; Guan, Xiaoyan; Gao, Shan; Yang, Aifu; Chen, Zhong; Sun, Hongjuan

    2015-05-01

    In this study, we investigated the bioremediation of petrochemical wastewater containing BTEX compounds by immobilized Comamonas sp. JB cells. Three kinds of magnetic nanoparticles were evaluated as immobilization supports for strain JB. After comparison with Fe3O4 and a-Fe2O3 nanoparticles, r-Fe2O3 nanoparticle was selected as the optimal immobilization support. The highest biodegradation activity of r-Fe2O3-magnetically immobilized cells was obtained when the concentration of r-Fe2O3 nanoparticle was 120 mg L(-1). Additionally, the recycling experiments demonstrated that the degradation activity of r-Fe2O3-magnetically immobilized cells was still high and led to less toxicity than untreated wastewater during the eight recycles. qPCR suggested the concentration of strain JB in r-Fe2O3-magnetically immobilized cells was evidently increased after eight cycles of degradation experiments. These results supported developing efficient biocatalysts using r-Fe2O3-magnetically immobilized cells and provided a promising technique for improving biocatalysts used in the bioremediation of not only petrochemical wastewater but also other hazardous wastewater.

  12. DNA typing by capillary electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, N.

    1997-10-08

    Capillary electrophoresis is becoming more and more important in nucleic acid analysis including DNA sequencing, typing and disease gene measurements. This work summarized the background of DNA typing. The recent development of capillary electrophoresis was also discussed. The second part of the thesis showed the principle of DNA typing based on using the allelic ladder as the absolute standard ladder in capillary electrophoresis system. Future work will be focused on demonstrating DNA typing on multiplex loci and examples of disease diagnosis in the on-line format of PCR-CE. Also capillary array electrophoresis system should allow high throughput, fast speed DNA typing. Only the introduction and conclusions for this report are available here. A reprint was removed for separate processing.

  13. Biological acetate production from carbon dioxide by Acetobacterium woodii and Clostridium ljungdahlii: The effect of cell immobilization.

    Science.gov (United States)

    Cheng, Hai-Hsuan; Syu, Jyun-Cyuan; Tien, Shih-Yuan; Whang, Liang-Ming

    2018-08-01

    This study investigated the acetate production from gas mixture of hydrogen (H 2 ) and carbon dioxide (CO 2 ) in the ratio of 7:3 using two acetogens: Acetobacterium woodii and Clostridium ljungdahlii. Batch result shows A. woodii performed two-phase degradation with the presence of glucose that lactate was produced from glucose and was reutilized for the production of butyrate and few acetate, while only acetate was detected when providing gas mixture. C. ljungdahlii produced butyrate and ethanol along with acetate when glucose was introduced, while only ethanol and acetate were found by feeding gas mixture. The acetate-to-ethanol (A/E) ratio can be enhanced by cell immobilization, while GAC immobilization produced only acetate and the production rate reached 0.072 mmol/d under fed-batch operation. Acetate production rate increased from 18 to 28 mmol/L/d with GAC immobilization when gas flowrate increased from 100 to 300 mL/min in anaerobic fluidized membrane bioreactor (AFMBR), and a highest A/E ratio of 30 implies the possible application of acetate recovery from H 2 and CO 2 . Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Isomaltulose production using free and immobilized Serratia ...

    African Journals Online (AJOL)

    André

    2016-05-18

    May 18, 2016 ... After 2 h of reaction time in shake flasks, a high production of ... immobilized cells in calcium alginate was studied in a packed bed bioreactor during seven days in a .... cell biomass was obtained from fermentation in a 6.6 L bioreactor .... carbohydrates were analyzed comparing their retention times with.

  15. A simplified technique for nasoendotracheal tube immobilization.

    OpenAIRE

    Berardo, N.; Leban, S. G.; Williams, F. A.

    1989-01-01

    A simplified technique for immobilization of a nasoendotracheal tube is described in which a wide strap of open cell, hypoallergenic, foam-backed fabric is secured to the patient's head with a Velcro fastener.

  16. Immobilization of Bacillus megaterium MTCC 2444 by Ca-alginate entrapment method for enhanced alkaline protease production

    Directory of Open Access Journals (Sweden)

    Soma Mrudula

    2012-02-01

    Full Text Available Optimization of culture conditions and immobilization parameters for alkaline protease production was carried out by employing Bacillus megaterium MTCC2444. The partially purified enzyme was tested for its stability in the presence of oxidants, surfactants and commercial detergents. The optimum temperature, pH, incubation time and inoculum size were 55 ºC, 11, 48 h, 1 %, respectively. Calcium alginate was used as the immobilization matrix and the effects of gel concentration, bead size, age of immobilized cells, solidification period and initial biomass concentration on alkaline protease production and cell leakage were investigated. The results indicated that the immobilization was most effective with 4 % gel concentration, bead size of 3 mm, 24 h aged immobilized cells for a solidification period of 12 h at 1.5 % initial biomass concentration. The enzyme showed good stability in the presence of oxidants, surfactants and commercial detergents.

  17. Cobalt immobilization by manganese oxidizing bacteria from the Indian ridge system

    Digital Repository Service at National Institute of Oceanography (India)

    Antony, R.; Sujith, P.P.; Fernandes, S.O.; Verma, P.; Khedekar, V.D.; LokaBharathi, P.A.

    Co immobilization by two manganese oxidizing isolates from Carlsberg Ridge waters (CR35 and CR48) was compared with that of Mn at same molar concentrations. At a lower concentration of 10 mu M, CR35 and CR48 immobilized 22 and 23 fM Co cell-1...

  18. Matrix-immobilized BMP-2 on microcontact printed fibronectin as in vitro tool to study BMP-mediated signaling and cell migration

    Directory of Open Access Journals (Sweden)

    Kristin eHauff

    2015-05-01

    Full Text Available During development, bone morphogenetic proteins (BMPs exert important functions in several tissues by regulating signaling for cell differentiation and migration. In vivo the extracellular matrix (ECM not only provides a support for adherent cells, but also presents a reservoir of growth factors (GFs. Several constituents of the ECM provide adhesive cues, which serve as binding sites for cell transmembrane receptors, such as integrins, which convey adhesion-mediated signaling to the intracellular compartment. Integrins do not function alone but rather crosstalk and cooperate with other receptors, such as GF receptors, in regulating cell responses to extracellular signals. To this, we present here the immobilization of BMP-2 onto cellular fibronectin (cFN, a key protein of the ECM, to investigate their impact on GF-mediated signaling and migration.Following biotinylation, BMP-2 was linked to biotinylated cFN using NeutrAvidin (NA as cross-linker. Characterization with QCM-D and ELISA confirmed the efficient immobilization of BMP-2 on cFN over a period of 24 h.To validate the bioactivity of matrix-immobilized BMP-2 (iBMP-2 we investigated short- and long-term responses of C2C12 myoblasts in comparison to soluble BMP-2 (sBMP-2 or in absence of GFs. Similarly to sBMP-2, iBMP-2 triggered Smad 1/5 phosphorylation and translocation into the nucleus corresponding to the activation of BMP-mediated Smad-dependent pathway. Additionally, successful suppression of myotube formation was observed after six days.We next implemented this approach to fabricate cFN micro patterned stripes by soft lithography. These stripes only allowed cell-surface interaction on the pattern due to passivation of the surface in between, thus serving as platform for studies on directed cell migration. During a 10 h-period, cells showed an increased migratory activity upon BMP-2 exposure.Thus, this versatile tool retains the GF's bioactivity and allows the presentation of ECM

  19. Biomedical applications of capillary electrophoresis

    International Nuclear Information System (INIS)

    Kartsova, L A; Bessonova, E A

    2015-01-01

    The review deals with modern analytical approaches used in capillary electrophoresis for solving medical and biological problems: search for biomarkers of various diseases and rapid diagnosis based on characteristic profiles of biologically active compounds by capillary electrophoresis with mass spectrometric detection; monitoring of the residual drugs in biological fluids for evaluating the efficiency of drug therapy; testing of the enantiomeric purity of pharmaceutical products; the use of novel materials as components of stationary and pseudo-stationary phases in capillary electrophoresis and capillary electrochromatography to increase the selectivity of separation of components of complex matrices; and identification of various on-line preconcentration techniques to reduce the detection limits of biologically active analytes. A topical trend in capillary electrophoresis required in clinical practice, viz., the design of microfluidic systems, is discussed. The bibliography includes 173 references

  20. Supramolecular gel electrophoresis of large DNA fragments.

    Science.gov (United States)

    Tazawa, Shohei; Kobayashi, Kazuhiro; Oyoshi, Takanori; Yamanaka, Masamichi

    2017-10-01

    Pulsed-field gel electrophoresis is a frequent technique used to separate exceptionally large DNA fragments. In a typical continuous field electrophoresis, it is challenging to separate DNA fragments larger than 20 kbp because they migrate at a comparable rate. To overcome this challenge, it is necessary to develop a novel matrix for the electrophoresis. Here, we describe the electrophoresis of large DNA fragments up to 166 kbp using a supramolecular gel matrix and a typical continuous field electrophoresis system. C 3 -symmetric tris-urea self-assembled into a supramolecular hydrogel in tris-boric acid-EDTA buffer, a typical buffer for DNA electrophoresis, and the supramolecular hydrogel was used as a matrix for electrophoresis to separate large DNA fragments. Three types of DNA marker, the λ-Hind III digest (2 to 23 kbp), Lambda DNA-Mono Cut Mix (10 to 49 kbp), and Marker 7 GT (10 to 165 kbp), were analyzed in this study. Large DNA fragments of greater than 100 kbp showed distinct mobility using a typical continuous field electrophoresis system. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Lactic acid production on liquid distillery stillage by Lactobacillus rhamnosus immobilized onto zeolite.

    Science.gov (United States)

    Djukić-Vuković, Aleksandra P; Mojović, Ljiljana V; Jokić, Bojan M; Nikolić, Svetlana B; Pejin, Jelena D

    2013-05-01

    In this study, lactic acid and biomass production on liquid distillery stillage from bioethanol production with Lactobacillus rhamnosus ATCC 7469 was studied. The cells were immobilized onto zeolite, a microporous aluminosilicate mineral and the lactic acid production with free and immobilized cells was compared. The immobilization allowed simple cell separation from the fermentation media and their reuse in repeated batch cycles. A number of viable cells of over 10(10) CFU g(-1) of zeolite was achieved at the end of fourth fermentation cycle. A maximal process productivity of 1.69 g L(-1), maximal lactic acid concentration of 42.19 g L(-1) and average yield coefficient of 0.96 g g(-1) were achieved in repeated batch fermentation on the liquid stillage without mineral or nitrogen supplementation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Heparin-immobilized hydroxyapatite nanoparticles as a lactoferrin delivery system for improving osteogenic differentiation of adipose-derived stem cells

    International Nuclear Information System (INIS)

    Kim, Sung Eun; Yun, Young-Pil; Kim, Hak-Jun; Lee, Deok-Won; Shim, Kyu-Sik; Jeon, Daniel I; Rhee, Jin-Kyu; Park, Kyeongsoon

    2016-01-01

    The aim of this study is to fabricate lactoferrin (LF)-carrying hydroxyapatite nanoparticles (HAp NPs) to enhance osteogenic differentiation of rabbit adipose-derived stem cells (rADSCs). HAp NPs were modified with heparin-dopamine (Hep-DOPA) (Hep-HAp) and further immobilized with LF (LF/Hep-HAp). Heparin immobilization on HAp NPs prevented aggregation of HAp NPs in aqueous solution and prolonged the release of LF from LF/Hep-HAp NPs. In vitro studies of rADSCs have demonstrated that LF-Hep/HAp NPs significantly increase alkaline phosphatase (ALP) activity, calcium deposition, and both mRNA expression of osteocalcin (OCN) and osteopontin (OPN) in comparison with HAp and Hep-HAp NPs. These results suggest that LF/Hep-HAp NPs can effectively induce osteogenic differentiation of rADSCs. (paper)

  3. Research on pre-staining gel electrophoresis

    International Nuclear Information System (INIS)

    Zhong Ruibo; Liu Yushuang; Zhang Ping; Liu Jingran; Zhao Guofen; Zhang Feng

    2014-01-01

    Background: Gel electrophoresis is a powerful biochemical separation technique. Most biological molecules are completely transparent in the visible region of light, so it is necessary to use staining to show the results after gel electrophoresis, and the general steps of conventional staining methods are time-consuming. Purpose: We try to develop a novel approach to simplify the gel electrophoresis: Pre-Staining Gel Electrophoresis (PSGE), which can make the gel electrophoresis results monitored in real time. Methods: Pre-stain the protein samples with Coomassie Brilliant Blue (CBB) for 30 min before loading the sample into the gel well. Results and Conclusion: PSGE can be successfully used to analyze the binding efficiency of Bovine Serum Albumin (BSA) and amphiphilic polymer via chemical coupling and physical absorption, and the double PSGE also shows a great potential in bio-analytical chemistry. (authors)

  4. Standardizing electrophoresis conditions: how to eliminate a major source of error in the comet assay.

    Directory of Open Access Journals (Sweden)

    Gunnar Brunborg

    2015-06-01

    Full Text Available In the alkaline comet assay, cells are embedded in agarose, lysed, and then subjected to further processing including electrophoresis at high pH (>13. We observed very large variations of mean comet tail lengths of cell samples from the same population when spread on a glass or plastic substrate and subjected to electrophoresis. These variations might be cancelled out if comets are scored randomly over a large surface, or if all the comets are scored. The mean tail length may then be representative of the population, although its standard error is large. However, the scoring process often involves selection of 50 – 100 comets in areas selected in an unsystematic way from a large gel on a glass slide. When using our 96-sample minigel format (1, neighbouring sample variations are easily detected. We have used this system to study the cause of the comet assay variations during electrophoresis and we have defined experimental conditions which reduce the variations to a minimum. We studied the importance of various physical parameters during electrophoresis: (i voltage; (ii duration of electrophoresis; (iii electric current; (iv temperature; and (v agarose concentration. We observed that the voltage (V/cm varied substantially during electrophoresis, even within a few millimetres of distance between gel samples. Not unexpectedly, both the potential ( V/cm and the time were linearly related to the mean comet tail, whereas the current was not. By measuring the local voltage with microelectrodes a few millimetres apart, we observed substantial local variations in V/cm, and they increased with time. This explains the large variations in neighbouring sample comet tails of 25% or more. By introducing simple technology (circulation of the solution during electrophoresis, and temperature control, these variations in mean comet tail were largely abolished, as were the V/cm variations. Circulation was shown to be particularly important and optimal conditions

  5. Immobilization of Ochrobactrum tritici As5 on PTFE thin films for arsenite biofiltration.

    Science.gov (United States)

    Branco, Rita; Sousa, Tânia; Piedade, Ana P; Morais, Paula V

    2016-03-01

    Ochrobactrum tritici SCII24T bacteria is an environmental strain with high capacity to resist to arsenic (As) toxicity, which makes it able to grow in the presence of As(III). The inactivation of the two functional arsenite efflux pumps, ArsB and ACR3_1, resulted in the mutant O. tritici As5 exhibiting a high accumulation of arsenite. This work describes a method for the immobilization of the mutant cells O. tritici As5, on a commercial polymeric net after sputtered modified by the deposition of poly(tetrafluoroethylene) (PTFE) thin films, and demonstrates the capacity of immobilized cells to accumulate arsenic from solutions. Six different set of deposition parameters for PTFE thin films were developed and tested in vitro regarding their ability to immobilize the bacterial cells. The surface that exhibited a mild zeta potential value, hydrophobic characteristics, the lowest surface free energy but with a high polar component and the appropriate ratio of chemical reactive groups allowed cells to proliferate and to grow as a biofilm. These immobilized cells maintained their ability to accumulate the surrounding arsenite, making it a great arsenic biofilter to be used in bioremediation processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Continuous production of ethanol from hexoses and pentoses using immobilized mixed cultures of Escherichia coli strains

    Science.gov (United States)

    Unrean, Pornkamol; Srienc, Friedrich

    2010-01-01

    We have developed highly efficient ethanologenic E. coli strains that selectively consume pentoses and/or hexoses. Mixed cultures of these strains can be used to selectively adjust the sugar utilization kinetics in ethanol fermentations. Based on the kinetics of sugar utilization, we have designed and implemented an immobilized cell system for the optimized continuous conversion of sugars into ethanol. The results confirm that immobilized mixed cultures support a simultaneous conversion of hexoses and pentoses into ethanol at high yield and at a faster rate than immobilized homogenous cells. Continuous ethanol production has been maintained for several weeks at high productivity with near complete sugar utilization. The control of sugar utilization using immobilized mixed cultures can be adapted to any composition of hexoses and pentoses by adjusting the strain distribution of immobilized cells. The approach, therefore, holds promise for ethanol fermentation from lignocellulosic hydrolysates where the feedstock varies in sugar composition. PMID:20699108

  7. Microfluidic device having an immobilized pH gradient and PAGE gels for protein separation and analysis

    Science.gov (United States)

    Sommer, Gregory J.; Hatch, Anson V.; Singh, Anup K.; Wang, Ying-Chih

    2012-12-11

    Disclosed is a novel microfluidic device enabling on-chip implementation of a two-dimensional separation methodology. Previously disclosed microscale immobilized pH gradients (IPG) are combined with perpendicular polyacrylamide gel electrophoresis (PAGE) microchannels to achieve orthogonal separations of biological samples. Device modifications enable inclusion of sodium dodecyl sulfate (SDS) in the second dimension. The device can be fabricated to use either continuous IPG gels, or the microscale isoelectric fractionation membranes we have also previously disclosed, for the first dimension. The invention represents the first all-gel two-dimensional separation microdevice, with significantly higher resolution power over existing devices.

  8. Modeling Substrate Utilization, Metabolite Production, and Uranium Immobilization in Shewanella oneidensis Biofilms

    Directory of Open Access Journals (Sweden)

    Ryan S. Renslow

    2017-06-01

    Full Text Available In this study, we developed a two-dimensional mathematical model to predict substrate utilization and metabolite production rates in Shewanella oneidensis MR-1 biofilm in the presence and absence of uranium (U. In our model, lactate and fumarate are used as the electron donor and the electron acceptor, respectively. The model includes the production of extracellular polymeric substances (EPS. The EPS bound to the cell surface and distributed in the biofilm were considered bound EPS (bEPS and loosely associated EPS (laEPS, respectively. COMSOL® Multiphysics finite element analysis software was used to solve the model numerically (model file provided in the Supplementary Material. The input variables of the model were the lactate, fumarate, cell, and EPS concentrations, half saturation constant for fumarate, and diffusion coefficients of the substrates and metabolites. To estimate unknown parameters and calibrate the model, we used a custom designed biofilm reactor placed inside a nuclear magnetic resonance (NMR microimaging and spectroscopy system and measured substrate utilization and metabolite production rates. From these data we estimated the yield coefficients, maximum substrate utilization rate, half saturation constant for lactate, stoichiometric ratio of fumarate and acetate to lactate and stoichiometric ratio of succinate to fumarate. These parameters are critical to predicting the activity of biofilms and are not available in the literature. Lastly, the model was used to predict uranium immobilization in S. oneidensis MR-1 biofilms by considering reduction and adsorption processes in the cells and in the EPS. We found that the majority of immobilization was due to cells, and that EPS was less efficient at immobilizing U. Furthermore, most of the immobilization occurred within the top 10 μm of the biofilm. To the best of our knowledge, this research is one of the first biofilm immobilization mathematical models based on experimental

  9. Usage of capillary electrophoresis for common hemoglobinopathies screening

    Directory of Open Access Journals (Sweden)

    Alireza Ebrahimi

    2016-06-01

    Full Text Available Hemoglobinopathies are most common inherited disorders in the world; approximately 7 percent of the worldwide population and 5-6 percent of population of Iran are carriers. The hemoglobin disorders inherit as autosomal recessive and are very common in the Mediterranean area and much of the Asia and Africa. The control of this inherited disorders need to genetic counseling and accurate screening by more advanced and more accurate methods. This study explains features of current Iran hemoglobin disorders, nominates the accessible methods for screening them and introduces the capillary zone electrophoresis as a rapid and more accurate method. The required data were extracted of various articles and then for good explanation, current Iran hemoglobinopathies properties were showed in the tables and electropherograms of important hemoglobin disorders in Iran population were provided for help to interpretation results of blood tests by capillary zone electrophoresis method. Hemoglobin disorders are including thalassemias and hemoglobin variants; Disruption in the production and malfunction of globin chains cause types of hemoglobin disorders. We cannot introduce one of clinical laboratory tests as critical and basic method for screening and distinguishing types of inherited hemoglobin disorders as alone. For distinguishing the types of them must be prepared enough information and data of the hemoglobin disorders and for more accurate analysis must be used simultaneously different methods as gel electrophoresis, high performance liquid chromatography, isoelectric focusing, capillary zone electrophoresis or molecular tests. The capillary electrophoresis is an accurate and rapid method for screening types of the hemoglobin disorders. Other side this method cannot analyze all of them, so must be used biochemical, biophysical and molecular methods for confirmation the results. This review showed we can use the capillary electrophoresis and HPLC as two

  10. Conducting polymer electrodes for gel electrophoresis.

    Directory of Open Access Journals (Sweden)

    Katarina Bengtsson

    Full Text Available In nearly all cases, electrophoresis in gels is driven via the electrolysis of water at the electrodes, where the process consumes water and produces electrochemical by-products. We have previously demonstrated that π-conjugated polymers such as poly(3,4-ethylenedioxythiophene (PEDOT can be placed between traditional metal electrodes and an electrolyte to mitigate electrolysis in liquid (capillary electroosmosis/electrophoresis systems. In this report, we extend our previous result to gel electrophoresis, and show that electrodes containing PEDOT can be used with a commercial polyacrylamide gel electrophoresis system with minimal impact to the resulting gel image or the ionic transport measured during a separation.

  11. Conducting polymer electrodes for gel electrophoresis.

    Science.gov (United States)

    Bengtsson, Katarina; Nilsson, Sara; Robinson, Nathaniel D

    2014-01-01

    In nearly all cases, electrophoresis in gels is driven via the electrolysis of water at the electrodes, where the process consumes water and produces electrochemical by-products. We have previously demonstrated that π-conjugated polymers such as poly(3,4-ethylenedioxythiophene) (PEDOT) can be placed between traditional metal electrodes and an electrolyte to mitigate electrolysis in liquid (capillary electroosmosis/electrophoresis) systems. In this report, we extend our previous result to gel electrophoresis, and show that electrodes containing PEDOT can be used with a commercial polyacrylamide gel electrophoresis system with minimal impact to the resulting gel image or the ionic transport measured during a separation.

  12. Biooxidation of 2-phenylethanol to phenylacetic acid by whole-cell Gluconobacter oxydans biocatalyst immobilized in polyelectrolyte complex capsules

    Czech Academy of Sciences Publication Activity Database

    Bertóková, A.; Vikartovská, A.; Bučko, M.; Gemeiner, P.; Tkáč, J.; Chorvát, D.; Štefuca, V.; Neděla, Vilém

    2015-01-01

    Roč. 33, č. 2 (2015), s. 111-120 ISSN 1024-2422 R&D Projects: GA ČR(CZ) GA14-22777S Institutional support: RVO:68081731 Keywords : Gluconobacter oxydans * natural flavors * phenylacetic acid * immobilized whole-cell biocatalyst * polyelectrolyte complex capsules * environmental scanning electron microscopy Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.892, year: 2015

  13. Ethanol production in an immobilized-cell column reactor: The effects of micro-aeration and dual feeds

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K

    1988-01-01

    Immobilized Saccharomyces cerevesiae cells adsorbed onto wood chips in a packed-bed bioreactor were used for ethanol fermentation from glucose solution. In aerobic and anaerobic batch experiments, an increase in initial glucose concentration resulted in a reduction of the specific growth rate, but no apparent glucose inhibition was found at initial glucose concentrations of ca <120 g/l. Since it is inevitable to use high substrate concentration to obtain high product concentration, experiments were performed in an immobilized-cell reactor (ICR) to examine any improvements achieved by a dual-feed mode over a continuous ICR system. The dual scheme can provide the same total amount of substrate while keeping the maximum substrate concentration to which the cells are exposed to about half of that in the single-feed case. In the dual-feed ICR, the ethanol production rate was 15% higher than that of the single-fed ICR. Experiments in skewed and vertical ICRs were performed to observe the difference in CO{sub 2} bubble removal; the bubbles were smoothly released in the skewed ICR compared to significant CO{sub 2} accumulation in the vertical ICR, and a biomass buildup on the wood surface was also observed. The experimental results indicate that trace amounts of dissolved oxygen stimulated fermentation rates, with one experiment showing a 31% improvement in ethanol productivity using aeration. At a controlled aeration rate, cells were observed to flocculate naturally onto the wood surface. Plugging of the void spaces, due to excess cell growth and intermittent CO{sub 2} holdup, was observed to begin at the base of the packed bed and progressed upward with time, thus undesirable channelling of liquid flow occurred. 200 refs., 76 figs., 21 tabs.

  14. Effect of immobilization of a bacterial consortium on diuron dissipation and community dynamics.

    Science.gov (United States)

    Bazot, Stéphane; Lebeau, Thierry

    2009-09-01

    This work intended to study the relationship between diuron herbicide dissipation and the population dynamics of co-cultivated Delftia acidovorans WDL34 (WDL34) and Arthrobacter sp. N4 (N4) for different cell formulations: free cells or immobilization in Ca-alginate beads of one or both strains. GFP-tagged WDL34 and N4 Gram staining allowed analyzing the cell growth and distribution of each strain in both beads and culture medium in the course of the time. Compared to the free cell co-culture of WDL34 and N4, immobilization of WDL34 in Ca-alginate beads co-cultivated with free N4 increased the dissipation rate of diuron by 53% (0.141 mg ml(-1) h(-1)). In that case, immobilization strongly modified the final equilibrium among both strains (highest total N4 to WDL34 ratio). Our results demonstrated that the inoculant formulation played a major role in the cell growth of each cultivated strain possibly increasing diuron dissipation. This optimized cell formulation may allow improving water and soil treatment.

  15. Immobilization of IFR salt wastes in mortar

    International Nuclear Information System (INIS)

    Fisher, D.F.; Johnson, T.R.

    1988-01-01

    Portland cement-base mortars are being considered for immobilizing chloride salt wastes from the fuel cycle of an integral fast reactor (IFR). The IFR is a sodium-cooled fast reactor with metal fuel. It has a close-coupled fuel cycle in which fission products are separated from the actinides in an electrochemical cell operating at 500 degrees C. This cell has a cadmium anode and a liquid salt electrolyte. The salt will be a low-melting mixture of alkaline and alkaline earth chlorides. This paper discusses one method being considered for immobilizing this treated salt, to disperse it in a portland cement-base motar, which would then be sealed in corrosion-resistant containers. For this application, the grout must be sufficiently fluid that it can be pumped into canisters where it will solidify into a strong, leach-resistant material

  16. EPDIM peptide-immobilized porous chitosan beads for enhanced wound healing: Preparation, characterizations and in vitro evaluation

    International Nuclear Information System (INIS)

    Bae, Jin Woo; Lee, Joon Hye; Choi, Won Sup; Lee, Dong Sin; Bae, Eun Hee; Park, Ki Dong

    2009-01-01

    EPDIM peptide is known to regulate cellular activities by interacting with α 3 β 1 integrin, which can be contributed to wound healing process. In this study, EPDIM was immobilized onto three-dimensional porous chitosan beads (χtopore) as a scaffold for enhanced wound healing. The significant decrease in contact angle indicates that EPDIM immobilization could lead to the enhanced surface wettability after its immobilization. The immobilized EPDIM was fairly distributed along its surface and the morphology was maintained even after the reaction. The immobilized amount of EPDIM was found to be about 5.68 nmol/mg of χtopore by amino acid analysis. To verify the complete removal of coupling agents after EPDIM immobilization, each coupling agent was quantitatively analyzed by LC-MS. In vitro proliferation rates of both NIH 3T3 and HaCaT showed that EPDIM immobilization onto χtopore could significantly enhance the growth rate of both cells, while the unmodified χtopore did not increase in cell number even after 15 days of culture. Therefore, these results demonstrate that EPDIM peptide-immobilized χtopore can be utilized as an attractive scaffold for enhanced wound healing.

  17. Comparative assessment of heavy metal removal by immobilized ...

    African Journals Online (AJOL)

    EJIRO

    Key words: Biosorption, bacteria, heavy metal, dead bacterial cells, immobilization. INTRODUCTION ... Moreover, the metals cannot be degraded to harmless products and ... a sterile plastic container and taken immediately to the laboratory.

  18. Laser-assisted immobilization of colloid silver nanoparticles on polyethyleneterephthalate

    Science.gov (United States)

    Siegel, Jakub; Lyutakov, Oleksiy; Polívková, Markéta; Staszek, Marek; Hubáček, Tomáš; Švorčík, Václav

    2017-10-01

    Immobilization of nanoobjects on the surface of underlying material belongs to current issues of material science. Such altered materials exhibits completely exceptional properties exploitable in a broad spectrum of industrially important applications ranging from catalysts up to health-care industry. Here we present unique approach for immobilization of electrochemically synthesized silver nanoparticles on polyethyleneterephthalate (PET) foil whose essence lies in physical incorporation of particles into thin polymer surface layer induced by polarized excimer laser light. Changes in chemical composition and surface structure of polymer after particle immobilization were recorded by wide range of analytical techniques such as ARXPS, EDX, RBS, AAS, Raman, ICP-MS, DLS, UV-vis, SEM, TEM, and AFM. Thorough analysis of both nanoparticles entering the immobilization step as well as modified PET surface allowed revealing the mechanism of immobilization process itself. Silver nanoparticles were physically embedded into a thin surface layer of polymer reaching several nanometers beneath the surface rather than chemically bonded to PET macromolecules. Laser-implanted nanoparticles open up new possibilities especially in the development of the next generation cell-conform antimicrobial coatings of polymeric materials, namely due to the considerable immobilization strength which is strong enough to prevent particle release into the surrounding environment.

  19. Immobilization of CotA, an extremophilic laccase from Bacillus subtilis, on glassy carbon electrodes for biofuel cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Beneyton, T.; El Harrak, A.; Griffiths, A.D.; Taly, V. [Institut de Science et d' Ingenierie Supramoleculaire, CNRS UMR, Strasbourg (France); Hellwig, P. [Institut de Chimie, Universite de Strasbourg, CNRS UMR, Strasbourg (France)

    2011-01-15

    Thanks to their high stability over a wide range of experimental conditions, extremophilic enzymes represent an interesting alternative to mesophilic enzymes as catalysts for biofuel cell applications. In the present work, we report for the first time the immobilization of a thermophilic laccase (CotA from Bacillus subtilis endospore coat) on glassy carbon electrodes functionalized via electrochemical reduction of in situ generated aminophenyl monodiazonium salts. We compare the performance of CotA-modified electrodes for the reduction of O{sub 2} to mutant variants and demonstrate that the measured electrical current is directly correlated to the catalytic efficiencies (k{sub cat}/K{sub m}) of the immobilized enzyme. CotA-modified electrodes showed an optimal operation temperature of 45-50 C and stable catalytic activity for at least 7 weeks. (author)

  20. Repair of γ-irradiation-induced DNA single-strand breaks in human bone marrow cells. Analysis of unfractionated and CD34+ cells using single-cell gel electrophoresis

    International Nuclear Information System (INIS)

    Lankinen, Maarit H.; Vilpo, Juhani A.

    1997-01-01

    Human bone marrow mononuclear cells (BMMNCs) were separated by density gradient centrifugation, and a subpopulation of progenitor cells was further isolated using anti-CD34-coated magnetic beads. The cells were irradiated with γ-rays (0.93-5.43 Gy) from a 137 Cs source. The extent of DNA damage, i.e., single-strand breaks (SSBs) and alkali-labile lesions of individual cells, was investigated using the alkaline single-cell gel electrophoresis technique. The irradiation resulted in a dose-dependent increase in DNA migration, reflecting the number of detectable DNA lesions. An approximately similar extent of SSB formation was observed in BMMNCs and CD34+ cells. Damage was repaired when the cells were incubated at 37C: a fast initial repair phase was followed by a slower rejoining of SSBs in both BMMNC and CD34+ cell populations. A significantly longer time was required to repair the lesions caused by 5.43 Gy than those caused by 0.93 Gy. In the present work we report, for the first time, the induction and repair of DNA SSBs at the level of single human bone marrow cells when exposed to ionizing radiation at clinically relevant doses. These data, together with our previous results with human blood granulocytes and lymphocytes, indicate an approximately similar extent of formation and repair of γ-irradiation-induced DNA SSBs in immature and mature human hematopoietic cells

  1. Generation of continuous packed bed reactor with PVA-alginate blend immobilized Ochrobactrum sp. DGVK1 cells for effective removal of N,N-dimethylformamide from industrial effluents

    Energy Technology Data Exchange (ETDEWEB)

    Sanjeev Kumar, S.; Kumar, M. Santosh [Department of Biochemistry, Gulbarga University, Gulbarga 585106, Karnataka (India); Siddavattam, D. [Department of Animal Sciences, University of Hyderabad, Hyderabad 500046 (India); Karegoudar, T.B., E-mail: goudartbk@gmail.com [Department of Biochemistry, Gulbarga University, Gulbarga 585106, Karnataka (India)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer Removal of DMF was compared by free and immobilized cells of Ochrobactrum sp. DGVK1. Black-Right-Pointing-Pointer Ochrobactrum sp. DGVK1 cells entrapped in PVA-alginate have shown more tolerance. Black-Right-Pointing-Pointer PVA-alginate beads removed DMF even in the presence of other organic solvents. Black-Right-Pointing-Pointer Removal of DMF from industrial effluents by PVA-alginate blended batch operations. Black-Right-Pointing-Pointer Development of industrially feasible remediation strategy for DMF removal. - Abstract: Effective removal of dimethylformamide (DMF), the organic solvent found in industrial effluents of textile and pharma industries, was demonstrated by using free and immobilized cells of Ochrobactrum sp. DGVK1, a soil isolate capable of utilizing DMF as a sole source of carbon, nitrogen. The free cells have efficiently removed DMF from culture media and effluents, only when DMF concentration was less than 1% (v/v). Entrapment of cells either in alginate or in polyvinyl alcohol (PVA) failed to increase tolerance limits. However, the cells of Ochrobactrum sp. DGVK1 entrapped in PVA-alginate mixed matrix tolerated higher concentration of DMF (2.5%, v/v) and effectively removed DMF from industrial effluents. As determined through batch fermentation, these immobilized cells have retained viability and degradability for more than 20 cycles. A continuous packed bed reactor, generated by using PVA-alginate beads, efficiently removed DMF from industrial effluents, even in the presence of certain organic solvents frequently found in effluents along with DMF.

  2. A simple and robust approach to immobilization of antibody fragments.

    Science.gov (United States)

    Ikonomova, Svetlana P; He, Ziming; Karlsson, Amy J

    2016-08-01

    Antibody fragments, such as the single-chain variable fragment (scFv), have much potential in research and diagnostics because of their antigen-binding ability similar to a full-sized antibody and their ease of production in microorganisms. Some applications of antibody fragments require immobilization on a surface, and we have established a simple immobilization method that is based on the biotin-streptavidin interaction and does not require a separate purification step. We genetically fused two biotinylation tags-the biotin carboxyl carrier protein (BCCP) or the AviTag minimal sequence-to six different scFvs (scFv13R4, scFvD10, scFv26-10, scFv3, scFv5, and scFv12) for site-specific biotinylation in vivo by endogenous biotin ligases produced by Escherichia coli. The biotinylated scFvs were immobilized onto streptavidin-coated plates directly from cell lysates, and immobilization was detected through enzyme-linked immunosorbent assays. All scFvs fusions were successfully immobilized, and scFvs biotinylated via the BCCP tag tended to immobilize better than those biotinylated via the AviTag, even when biotinylation efficiency was improved with the biotin ligase BirA. The ability of immobilized scFvs to bind antigens was confirmed using scFv13R4 and scFvD10 with their respective targets β-galactosidase and bacteriophage lambda head protein D (gpD). The immobilized scFv13R4 bound to β-galactosidase at the same level for both biotinylation tags when the surface was saturated with the scFv, and immobilized scFvs retained their functionality for at least 100days after immobilization. The simplicity and robustness of our method make it a promising approach for future applications that require antibody fragment immobilization. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Moving into advanced nanomaterials. Toxicity of rutile TiO{sub 2} nanoparticles immobilized in nanokaolin nanocomposites on HepG2 cell line

    Energy Technology Data Exchange (ETDEWEB)

    Bessa, Maria João, E-mail: mjbessa8@gmail.com [Department of Environmental Health, Portuguese National Institute of Health, Rua Alexandre Herculano, 321, 4000-055 Porto (Portugal); Costa, Carla, E-mail: cstcosta@gmail.com [Department of Environmental Health, Portuguese National Institute of Health, Rua Alexandre Herculano, 321, 4000-055 Porto (Portugal); EPIUnit - Institute of Public Health, University of Porto, Rua das Taipas 135, 4050-600, Porto (Portugal); Reinosa, Julian, E-mail: jjreinosa@icv.csic.es [Electroceramic Department, Instituto de Cerámica y Vidrio, CSIC, Campus de Cantoblanco, Calle de Kelson, 5, 28049 Madrid (Spain); Pereira, Cristiana, E-mail: cristianacostapereira@gmail.com [Department of Environmental Health, Portuguese National Institute of Health, Rua Alexandre Herculano, 321, 4000-055 Porto (Portugal); EPIUnit - Institute of Public Health, University of Porto, Rua das Taipas 135, 4050-600, Porto (Portugal); Fraga, Sónia, E-mail: teixeirafraga@hotmail.com [Department of Environmental Health, Portuguese National Institute of Health, Rua Alexandre Herculano, 321, 4000-055 Porto (Portugal); EPIUnit - Institute of Public Health, University of Porto, Rua das Taipas 135, 4050-600, Porto (Portugal); Fernández, José, E-mail: jfernandez@icv.csic.es [Electroceramic Department, Instituto de Cerámica y Vidrio, CSIC, Campus de Cantoblanco, Calle de Kelson, 5, 28049 Madrid (Spain); Bañares, Miguel A., E-mail: miguel.banares@csic.es [Catalytic Spectroscopy Laboratory, Instituto de Catálisis y Petroleoquímica, ICP-CSIC, Madrid (Spain); and others

    2017-02-01

    Immobilization of nanoparticles on inorganic supports has been recently developed, resulting in the creation of nanocomposites. Concerning titanium dioxide nanoparticles (TiO{sub 2} NPs), these have already been developed in conjugation with clays, but so far there are no available toxicological studies on these nanocomposites. The present work intended to evaluate the hepatic toxicity of nanocomposites (C-TiO{sub 2}), constituted by rutile TiO{sub 2} NPs immobilized in nanokaolin (NK) clay, and its individual components. These nanomaterials were analysed by means of FE-SEM and DLS analysis for physicochemical characterization. HepG2 cells were exposed to rutile TiO{sub 2} NPs, NK clay and C-TiO{sub 2} nanocomposite, in the presence and absence of serum for different exposure periods. Possible interferences with the methodological procedures were determined for MTT, neutral red uptake, alamar blue (AB), LDH, and comet assays, for all studied nanomaterials. Results showed that MTT, AB and alkaline comet assay were suitable for toxicity analysis of the present materials after slight modifications to the protocol. Significant decreases in cell viability were observed after exposure to all studied nanomaterials. Furthermore, an increase in HepG2 DNA damage was observed after shorter periods of exposure in the absence of serum proteins and longer periods of exposure in their presence. Although the immobilization of nanoparticles in micron-sized supports could, in theory, decrease the toxicity of single nanoparticles, the selection of a suitable support is essential. The present results suggest that NK clay is not the appropriate substrate to decrease TiO{sub 2} NPs toxicity. Therefore, for future studies, it is critical to select a more appropriate substrate for the immobilization of TiO{sub 2} NPs. - Highlights: • Only the MTT and AB assays were found to be suitable for cytotoxicity assessment. • Alkaline comet assay was also appropriate for genotoxicity evaluation

  4. DNA double-strand break measurement in mammalian cells by pulsed-field gel electrophoresis: an approach using restriction enzymes and gene probing

    International Nuclear Information System (INIS)

    Loebrich, M.; Ikpeme, S.; Kiefer, J.

    1994-01-01

    DNA samples prepared from human SP 3 cells, which had not been exposed to various doses of X-ray, were treated with NotI restriction endonuclease before being run in a contour-clamped homogeneous electrophoresis system. The restriction enzyme cuts the DNA at defined positions delivering DNA sizes which can be resolved by pulsed-field gel electrophoresis (PFGE). In order to investigate only one of the DNA fragments, a human lactoferrin cDNA, pHL-41, was hybridized to the DNA separated by PFGE. As a result, only the DNA fragment which contains the hybridized gene was detected resulting in a one-band pattern. The decrease of this band was found to be exponential with increasing radiation dose. From the slope, a double-strand break induction rate of (6.3±0.7) x 10 -3 /Mbp/Gy was deduced for 80 kV X-rays. (Author)

  5. Cooperative control of blood compatibility and re-endothelialization by immobilized heparin and substrate topography.

    Science.gov (United States)

    Ding, Yonghui; Yang, Meng; Yang, Zhilu; Luo, Rifang; Lu, Xiong; Huang, Nan; Huang, Pingbo; Leng, Yang

    2015-03-01

    A wide variety of environmental cues provided by the extracellular matrix, including biophysical and biochemical cues, are responsible for vascular cell behavior and function. In particular, substrate topography and surface chemistry have been shown to regulate blood and vascular compatibility individually. The combined impact of chemical and topographic cues on blood and vascular compatibility, and the interplay between these two types of cues, are subjects that are currently being explored. In the present study, a facile polydopamine-mediated approach is introduced for immobilization of heparin on topographically patterned substrates, and the combined effects of these cues on blood compatibility and re-endothelialization are systematically investigated. The results show that immobilized heparin and substrate topography cooperatively modulate anti-coagulation activity, endothelial cell (EC) attachment, proliferation, focal adhesion formation and endothelial marker expression. Meanwhile, the substrate topography is the primary determinant of cell alignment and elongation, driving in vivo-like endothelial organization. Importantly, combining immobilized heparin with substrate topography empowers substantially greater competitive ability of ECs over smooth muscle cells than each cue individually. Moreover, a model is proposed to elucidate the cooperative interplay between immobilized heparin and substrate topography in regulating cell behavior. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  6. Parameters and kinetics of olive mill wastewater dephenolization by immobilized Rhodotorula glutinis cells.

    Science.gov (United States)

    Bozkoyunlu, Gaye; Takaç, Serpil

    2014-01-01

    Olive mill wastewater (OMW) with total phenol (TP) concentration range of 300-1200 mg/L was treated with alginate-immobilized Rhodotorula glutinis cells in batch system. The effects of pellet properties (diameter, alginate concentration and cell loading (CL)) and operational parameters (initial TP concentration, agitation rate and reusability of pellets) on dephenolization of OMW were studied. Up to 87% dephenolization was obtained after 120 h biodegradations. The utilization number of pellets increased with the addition of calcium ions into the biodegradation medium. The overall effectiveness factors calculated for different conditions showed that diffusional limitations arising from pellet size and pellet composition could be neglected. Mass transfer limitations appeared to be more effective at high substrate concentrations and low agitation rates. The parameters of logistic model for growth kinetics of R. glutinis in OMW were estimated at different initial phenol concentrations of OMW by curve-fitting of experimental data with the model.

  7. Bioremediation of Fluorophenols by Glycosylation with Immobilized Marine Microalga Amphidinium Crassum

    Directory of Open Access Journals (Sweden)

    Kei Shimoda

    2010-01-01

    Full Text Available Fluorophenols are used as agrochemicals and released into environment as pollutants. Cultured marine microalga Amphidinium crassum ( Gymnodinium glucosylated 2-fluorophenol ( 1 , 3-fluorophenol ( 2 , and 4-fluorophenol ( 3 to the corresponding β-D-glucosides, ie, 2-fluorophenyl β-D-glucoside ( 4 , 60 μg/g cells, 3-fluorophenyl β-D-glucoside ( 5 , 20 μg/g cells, and 4-fluorophenyl β-D-glucoside ( 6 , 40 μg/g cells. On the other hand, 2-, 3-, and 4-fluorophenols were efficiently converted by immobilized A. crassum in sodium alginate gel to give their β-D-glucosides in higher yields ( 4 : 140 μg/g cells; 5 : 60 μg/g cells; 6 : 100 μg/g cells. In repetitive batch use, the immobilized cells of A. crassum maintained the potential for the glucosylation of the substrate fluorophenol after 5 times of usage.

  8. Distribution of hemoglobinopathies in patients presenting for electrophoresis and comparison of result with High performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    R Jha

    2015-09-01

    Full Text Available Background: Nearly 226 million carriers of thalassemias and abnormal hemoglobin are present worldwide according to the World Health Organization (WHO. The laboratory plays an important role in the investigation of the thalassemias and hemoglobinopathies. Cellulose acetate electrophoresis at alkaline pH and diagnosis based mainly on visual impression of thickness of band may miss the thalassemic trait patients. The aim of this study was to find out different hemoglobinopathies and thalassemia presenting in our hospital and to compare electrophoresis results with HPLC.Materials and Methods: This study was performed in the hematopathology section of Department of Pathology of Tribhuvan University Teaching Hospital on cases sent for electrophoresis during 18 months period from October 2013 to March 2015 and included hemoglobinopathies and thalassemias identified by either electrophoresis or HPLC. 97 cases fulfilled the inclusion criteria and thus were included in the study. Electrophoresis at alkaline pH was done in all whereas HPLC was performed in 27 cases.Results: A sharp peak of hemoglobinopathies and thalassemias was seen in Tharu community though other communities are also affected. Thalassemia trait was the most common diagnosis (26.8% followed by sickle cell anemia (21.6%.  Electrophoresis was efficient in detecting some alpha thalassemia variants but missed many cases of beta thalassemia trait.Conclusion: Beta Thalassemia trait and sickle cell anemia both are common in Nepal , along with some other hemoglobinopathies  A sharp peak of hemoglobinopathies and thalassemias are seen in Tharu community. These abnormal hemoglobins and thalassemias are mainly seen in Terai region. Electrophoresis fails to quantify hemoglobin percentage and thus is not appropriate test in beta thalassemia screening. 

  9. [Biodegradation of methyl tert-butyl ether by stabilized immobilized Methylibium petroleiphilum PM1 cells and its biodegradation kinetics analysis].

    Science.gov (United States)

    Cheng, Zhuo-wei; Fu, Ling-xiao; Jiang, Yi-feng; Chen, Jian-meng; Zhang, Rong

    2011-05-01

    Methylibium petroleiphilum PM1, which is capable of degrading methyl tert-butyl ether (MTBE) , was immobilized in calcium alginate gel beads. Several methods were explored to increase the strength of these gel beads. The central composite design analysis indicated that the introduction of 0.2 mol x L(-1) Ca2+ into the crosslinking solution, 1.38 mmol x L(-1) Ca2+ into the growth medium and 0.1% polyethyleneimine (PEI) as the chemical crosslinking agent could increase the stability of the Ca-alginate gel beads with no loss of biodegradation activity. The stabilized immobilized cells could be used 400 h continuously with no breakage and no bioactivity loss. Examination of scanning electron microscope demonstrated that a membrane surrounding the gel beads was formed and the cells could grow and breed well in the stabilized calcium alginate gel beads. Kinetic analysis of the gel bead-degradation indicated that the rate-limiting step was biochemical process instead of intraparticle diffusion process. The diameter of 3 mm affected the biodegradability less while high concentration of PEI induced much more serious mass transfer restraint.

  10. Mutagenicity assessment of two herbal medicines, Urtan and Carmint in human leukocytes by single cell gel electrophoresis

    International Nuclear Information System (INIS)

    Jalili, M.; Hatami, A.; Kalantari, H.; Kalantar, E.

    2006-01-01

    The use of herbal medicine is an old and still widespread particle, which makes studies their genotoxicity essential. Urtan and Carmint are examples of herbal medicines used in Iran which used for the treatment of hyperplasia, diuretic, urinary diffusion and antispasmodic action, carminative gastrointestinal disfunction respectively. The aim of this study was to evaluate the mutagenicity of these herbal medicines in human leukocytes by Single Cell Gel Electrophoresis (SCGE). Both the herbal medicines were used at four concentrations (0.046, 0.092, 0.138 and 0.184/ 100 ml). The results were compared against positive (Cr VI) and negative (no mutagen) control groups. Fluorescence microscope was used to observe the DNA damage in randomly selected cells, which were stained with ethidium bromide. Microscopic observation of the affected cells due to Urtan and Carmint was encouraging as compared to previous studies using SCGE. Both Urtan and Carmint exhibited considerable DNA damage to the blood cells. For example, Urtan at o.184 g/100ml concentration had almost 23% mutagenic effect and as the concentration increased the mutagenic effect also increased. Similarly Carmint exhibited considerable DNA damage on blood cells. Therefore, both the herbal medicines may have some mutagenic effect. (author)

  11. DNA gel electrophoresis: the reptation model(s).

    Science.gov (United States)

    Slater, Gary W

    2009-06-01

    DNA gel electrophoresis has been the most important experimental tool to separate DNA fragments for several decades. The introduction of PFGE in the 1980s and capillary gel electrophoresis in the 1990s made it possible to study, map and sequence entire genomes. Explaining how very large DNA molecules move in a gel and why PFGE is needed to separate them has been an active field of research ever since the launch of the journal Electrophoresis. This article presents a personal and historical overview of the development of the theory of gel electrophoresis, focusing on the reptation model, the band broadening mechanisms, and finally the factors that limit the read length and the resolution of electrophoresis-based sequencing systems. I conclude with a short discussion of some of the questions that remain unanswered.

  12. Preparation of metal-resistant immobilized sulfate reducing bacteria beads for acid mine drainage treatment.

    Science.gov (United States)

    Zhang, Mingliang; Wang, Haixia; Han, Xuemei

    2016-07-01

    Novel immobilized sulfate-reducing bacteria (SRB) beads were prepared for the treatment of synthetic acid mine drainage (AMD) containing high concentrations of Fe, Cu, Cd and Zn using up-flow anaerobic packed-bed bioreactor. The tolerance of immobilized SRB beads to heavy metals was significantly enhanced compared with that of suspended SRB. High removal efficiencies of sulfate (61-88%) and heavy metals (>99.9%) as well as slightly alkaline effluent pH (7.3-7.8) were achieved when the bioreactor was fed with acidic influent (pH 2.7) containing high concentrations of multiple metals (Fe 469 mg/L, Cu 88 mg/L, Cd 92 mg/L and Zn 128 mg/L), which showed that the bioreactor filled with immobilized SRB beads had tolerance to AMD containing high concentrations of heavy metals. Partially decomposed maize straw was a carbon source and stabilizing agent in the initial phase of bioreactor operation but later had to be supplemented by a soluble carbon source such as sodium lactate. The microbial community in the bioreactor was characterized by denaturing gradient gel electrophoresis (DGGE) and sequencing of partial 16S rDNA genes. Synergistic interaction between SRB (Desulfovibrio desulfuricans) and co-existing fermentative bacteria could be the key factor for the utilization of complex organic substrate (maize straw) as carbon and nutrients source for sulfate reduction. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Pulsed-field gel electrophoresis of bacterial chromosomes.

    Science.gov (United States)

    Mawer, Julia S P; Leach, David R F

    2013-01-01

    The separation of fragments of DNA by agarose gel electrophoresis is integral to laboratory life. Nevertheless, standard agarose gel electrophoresis cannot resolve fragments bigger than 50 kb. Pulsed-field gel electrophoresis is a technique that has been developed to overcome the limitations of standard agarose gel electrophoresis. Entire linear eukaryotic chromosomes, or large fragments of a chromosome that have been generated by the action of rare-cutting restriction endonucleases, can be separated using this technique. As a result, pulsed-field gel electrophoresis has many applications, from karyotype analysis of microbial genomes, to the analysis of chromosomal strand breaks and their repair intermediates, to the study of DNA replication and the identification of origins of replication. This chapter presents a detailed protocol for the preparation of Escherichia coli chromosomal DNA that has been embedded in agarose plugs, digested with the rare-cutting endonuclease NotI, and separated by contour-clamped homogeneous field electrophoresis. The principles in this protocol can be applied to the separation of all fragments of DNA whose size range is between 40 kb and 1 Mb.

  14. Contribution of Extracellular Polymeric Substances from Shewanella sp. HRCR-1 Biofilms to U(VI) Immobilization

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Bin; Ahmed, B.; Kennedy, David W.; Wang, Zheming; Shi, Liang; Marshall, Matthew J.; Fredrickson, Jim K.; Isern, Nancy G.; Majors, Paul D.; Beyenal, Haluk

    2011-06-05

    The goal of this study was to quantify the contribution of extracellular polymeric substances (EPS) in U(VI) immobilization by Shewanella sp. HRCR-1. Through comparison of U(VI) immobilization using cells with bound EPS (bEPS) and cells without EPS, we showed that i) bEPS from Shewanella sp. HRCR-1 biofilms contributed significantly to U(VI) immobilization, especially at low initial U(VI) concentrations, through both sorption and reduction; ii) bEPS could be considered as a functional extension of the cells for U(VI) immobilization and they likely play more important roles at initial U(VI) concentrations; and iii) U(VI) reduction efficiency was found to be dependent upon initial U(VI) concentration and the efficiency decreased at lower concentrations. To quantify relative contribution of sorption and reduction in U(VI) immobilization by EPS fractions, we isolated loosely associated EPS (laEPS) and bEPS from Shewanella sp. HRCR-1 biofilms grown in a hollow fiber membrane biofilm reactor and tested their reactivity with U(V). We found that, when in reduced form, the isolated cell-free EPS fractions could reduce U(VI). Polysaccharides in the EPS likely contributed to U(VI) sorption and dominated reactivity of laEPS while redox active components (e.g., outer membrane c-type cytochromes), especially in bEPS, might facilitate U(VI) reduction.

  15. Contribution of extracellular polymeric substances from Shewanella sp. HRCR-1 biofilms to U(VI) immobilization.

    Science.gov (United States)

    Cao, Bin; Ahmed, Bulbul; Kennedy, David W; Wang, Zheming; Shi, Liang; Marshall, Matthew J; Fredrickson, Jim K; Isern, Nancy G; Majors, Paul D; Beyenal, Haluk

    2011-07-01

    The goal of this study was to quantify the contribution of extracellular polymeric substances (EPS) to U(VI) immobilization by Shewanella sp. HRCR-1. Through comparison of U(VI) immobilization using cells with bound EPS (bEPS) and cells with minimal EPS, we show that (i) bEPS from Shewanella sp. HRCR-1 biofilms contribute significantly to U(VI) immobilization, especially at low initial U(VI) concentrations, through both sorption and reduction; (ii) bEPS can be considered a functional extension of the cells for U(VI) immobilization and they likely play more important roles at lower initial U(VI) concentrations; and (iii) the U(VI) reduction efficiency is dependent upon the initial U(VI) concentration and decreases at lower concentrations. To quantify the relative contributions of sorption and reduction to U(VI) immobilization by EPS fractions, we isolated loosely associated EPS (laEPS) and bEPS from Shewanella sp. HRCR-1 biofilms grown in a hollow fiber membrane biofilm reactor and tested their reactivity with U(VI). We found that, when reduced, the isolated cell-free EPS fractions could reduce U(VI). Polysaccharides in the EPS likely contributed to U(VI) sorption and dominated the reactivity of laEPS, while redox active components (e.g., outer membrane c-type cytochromes), especially in bEPS, possibly facilitated U(VI) reduction.

  16. Synthesis of Pt-immobilized on silica and polystyrene-encapsulated silica and their applications as electrocatalysts in the proton exchange membrane fuel cell

    International Nuclear Information System (INIS)

    Yi, Sung-Chul; Kim, Chang Young; Jung, Chi Young; Jeong, Sung Hoon; Kim, Wha Jung

    2011-01-01

    Nano sized Pt particles were successfully immobilized onto SiO 2 and polystyrene-encapsulated silica core shell (SiO 2 @PS). To make the immobilization of Pt onto both silica and polystyrene-encapsulated silica core shell, SiO 2 was first functionalized with -NH 2 using 3-amino propyl trimethoxysilane (APTMS) while for core shell, the negatively charged surface of polystyrene (PS) was changed with positive charge by cationic surfactant such as cetyltrimethylammonium chloride (CTACl) to make the formation of SiO 2 shell on preformed PS sphere. Transmission electron micrograph (TEM) images shows that Pt nanoparticles immobilized onto SiO 2 and SiO 2 @PS were to be 3-4 nm without agglomeraiton. The energy dispersive spectroscope (EDS) shows that Pt contents on both SiO 2 and SiO 2 @PS were to be 21.45% and 20.28%, respectively. In case of Pt-SiO 2 @PS, it is believed that Pt should have been immobilized onto PS surface and pore within SiO 2 shell as well as SiO 2 surface. The MEA fabricated with Pt-SiO 2 @PS shows better cell performance than of Pt-SiO 2 .

  17. Gel electrophoresis of inorganic cations

    International Nuclear Information System (INIS)

    Schoenhofer, F.; Grass, F.

    1978-01-01

    In order to be able to separate the largest possible amounts of substance, polyacryl amide gel (PAA) and silica gel are used as carrier for the electrophoresis. Milligramme quantities can easily be separated on PAA gel plates. Electrophoretic ion focussing considerably improves it. Separations of Sr/Y and lanthanoids were carried out. The behaviour of the readily soluble complexing agent acids on silica gel thin layers was minutely investigated and an interpretation of the focussing effect was derived. The conditions for separating radionuclides were optimized. A further improved separation can be achieved by a time sequence combination of normal electrophoresis and ion focussing. Selective isolation methods are advantageous to determine radionuclide traces in environmental samples. The selective adsorption on preformed deposits was transferred to electrophoresis. After pre-investigations on silica gel layers, strontium and barium could also be retained on PAA gel and radium on strontium sulphate in PAA, whereas the disturbing calcium can easily pass through. Cesium can also be retained by prussian blue in the electrophoresis. (orig.) [de

  18. Bioprocessing: Prospects for space electrophoresis

    Science.gov (United States)

    Bier, M.

    1977-01-01

    The basic principles of electrophoresis are reviewed in light of its past contributions to biology and medicine. The near-zero gravity environment of orbiting spacecraft may present some unique advantages for a variety of processes, by abolishing the major source of convection in fluids. As the ground-based development of electrophoresis was heavily influenced by the need to circumvent the effects of gravity, this process should be a prime candidate for space operation. Nevertheless, while a space facility for electrophoresis may overcome the limitations imposed by gravity, it will not necessarily overcome all problems inherent in electrophoresis. These are, mainly, electroosmosis and the dissipation of the heat generated by the electric field. The NASA program has already led to excellent coatings to prevent electroosmosis, while the need for heat dissipation will continue to impose limits on the actual size of equipment. It is also not excluded that, once the dominant force of gravity is eliminated, disturbances in fluid stability may originate from weaker forces, such as surface tension.

  19. Pigment Production from Immobilized Monascus sp. Utilizing Polymeric Resin Adsorption

    OpenAIRE

    Evans, Patrick J.; Wang, Henry Y.

    1984-01-01

    Pigment production by the fungus Monascus sp. was studied to determine why Monascus sp. provides more pigment in solid culture than in submerged culture. Adding a sterilized nonionic polymeric adsorbent resin directly to the growing submerged culture did not enhance the pigment production, thus indicating that pigment extraction is probably not a factor. Monascus cells immobilized in hydrogel were studied and exhibited decreased pigment production as a result of immobilization. This result is...

  20. Bioethanol production from starchy biomass by direct fermentation using saccharomyces diastaticus in batch free and immobilized cell systems

    Energy Technology Data Exchange (ETDEWEB)

    Kilonzo, P.M.; Margaritis, A. [University of Western Ontario, London, ON (Canada). Dept. of Chemical and Biochemical Engineering; Yu, J.; Ye, Q. [East China Univ. of Science and Technology, Shanghai (China). Biochemical Engineering Research Inst. and State Key Lab

    2006-07-01

    The feasibility of using amylolytic yeasts for the direct fermentation of starchy biomass to ethanol was discussed. Although amylolytic yeasts such as Saccharomycopsis, Lipomyces, and Schwaniomyces secrete both {alpha}-amylase and glucoamylase enzymes that synergistically enhance starch degradation, they are not suitable for industrial bio-ethanol production because of low tolerance for ethanol and slow fermentation rate. For that reason, this study examined the direct ethanol fermentation of soluble starch or dextrin with the amylolytic yeast Saccharomyces diastaticus in batch free and immobilized cells systems. Saccharomyces diastaticus secretes glucoamylase and can therefore assimilate and ferment starch and starch-like biomass. The main focus of the study was on parameters leading to higher ethanol yields from high concentration of dextrin and soluble starch using batch cultures. A natural attachment method was proposed in which polyurethane foam sheets were used as the carrier for amylolytic yeasts immobilization in ethanol fermentations. The support was chosen because it was inexpensive, autoclavable, pliable and could be tailored to suit process requirements regarding net surface charge, shape and size. It was found that Saccharomyces diastaticus was very efficient in terms of fermentation of high initial concentrations of dextrin or soluble starch. Higher concentrations of ethanol were produced. In batch fermentations, the cells fermented high dextrin concentrations more efficiently. In particular, in batch fermentation, more than 92 g-L of ethanol was produced from 240 g-L of dextrin, at conversion efficiency of 90 per cent. The conversion efficiency decreased to 60 per cent but a higher final ethanol concentration of 147 g/L was attained with a medium containing 500 g/L of dextrin. In an immobilized cell bioreactor, Saccharomyces diastaticus produced 83 g/L of ethanol from 240 g/L of dextrin, corresponding to ethanol volumetric productivity of 9.1 g

  1. Two-Dimensional Electrophoresis Study of Lactobacillus delbrueckii subsp. bulgaricus Thermotolerance

    OpenAIRE

    Gouesbet, Gwenola; Jan, Gwenael; Boyaval, Patrick

    2002-01-01

    The response of Lactobacillus delbrueckii subsp. bulgaricus cells to heat stress was studied by use of a chemically defined medium. Two-dimensional electrophoresis (2-DE) analysis was used to correlate the kinetics of heat shock protein (HSP) induction with cell recovery from heat injury. We demonstrated that enhanced viability, observed after 10 min at 65°C, resulted from the overexpression of HSP and from mechanisms not linked to protein synthesis. In order to analyze the thermoadaptation m...

  2. Actin Immobilization on Chitin for Purifying Myosin II: A Laboratory Exercise That Integrates Concepts of Molecular Cell Biology and Protein Chemistry

    Science.gov (United States)

    de Souza, Marcelle Gomes; Grossi, Andre Luiz; Pereira, Elisangela Lima Bastos; da Cruz, Carolina Oliveira; Mendes, Fernanda Machado; Cameron, Luiz Claudio; Paiva, Carmen Lucia Antao

    2008-01-01

    This article presents our experience on teaching biochemical sciences through an innovative approach that integrates concepts of molecular cell biology and protein chemistry. This original laboratory exercise is based on the preparation of an affinity chromatography column containing F-actin molecules immobilized on chitin particles for purifying…

  3. Study of the interaction of boron-containing amino acids for the neutron capture therapy with biologically interesting compounds by using 'three-spot zone electrophoresis'

    International Nuclear Information System (INIS)

    Kitaoka, Yoshinori; Kobayashi, Mitsue; Morimoto, Tsuguhiro; Kirihata, Mitsunori; Ichimoto, Itsuo.

    1995-01-01

    As the boron carriers for boron neutron capture therapy, p-borono phenylalanine (BPA) is the boron compound which has been clinically used together with sodium borocaptate. It was found by the electrophoresis behavior that the BPA interacted with organic carboxylic acids in its dissolved state. In this paper, the electrophoresis behavior of general amino acids as seen in three-spot zone electrophoresis and the peculiar interaction of the amino acids having dihydroxyboryl radical are described. Zone electrophoresis has been developed as separation means, and three-spot process excludes the errors due to accidental factors as far as possible. The behaviors of zone electrophoresis of ordinary neutral amino acids, orthoboric acid and p-BPA are reported. For utilizing the features of boron neutron capture therapy, it is necessary to develop the carrier which is singularly taken into cancer cells. There is not a good method for discriminating normal cells and cancer cells. As for the administration of BPA to patients, its solubility is insufficient, therefore, its fructose complex has been used. The research on the biochemical peculiarity of boron is important. (K.I.)

  4. Production of organic acids in an immobilized cell reactor using ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-09-17

    Sep 17, 2008 ... 1Faculty of Chemical Engineering, Noushirvani University of Technology, Babol, Iran. 2Faculty of Civil ... downstream, immobilization was the method of choice which was ..... These methods can be applied to various.

  5. Efficient production of succinic acid in immobilized fermentation with crude glycerol from Escherichia coli

    Directory of Open Access Journals (Sweden)

    Nik Nor Aziati, A.A.

    2017-10-01

    Full Text Available The increase in the price of commercial succinic acid has necessitated the need for its synthesis from waste materials such as glycerol. Glycerol residue is a waste product of Oleochemical production which is cheaply available and a very good source of carbon. The use of immobilized cells can further reduce the overall cost of the production process. This study primarily aims to produce succinic acid from glycerol residue through the use of immobilized Escherichia coli in a batch fermentation process. The parameters which affect bacterial fermentation process such as the mass substrate, temperature, inoculum size and duration of fermentation were screened using One-Factor-At-a-Time (OFAT method. The result of the screening process shows that a substrate (glycerol concentration of 30 g, inoculum size 20% v/v, and time 4 h produced the maximum succinic acid concentration of 117.99 g/L. The immobilized cells were found to be stable as well as retain their fermentative ability up to the 6th cycle of recycling, thereby presenting as an advantage over the free cell system. Therefore, conclude that using immobilized cells can contribute immensely to the cost-effective production of succinic acid from glycerol residue.

  6. Limb immobilization and corticobasal syndrome.

    Science.gov (United States)

    Graff-Radford, Jonathan; Boeve, Bradley F; Drubach, Daniel A; Knopman, David S; Ahlskog, J Eric; Golden, Erin C; Drubach, Dina I; Petersen, Ronald C; Josephs, Keith A

    2012-12-01

    Recently, we evaluated two patients with corticobasal syndrome (CBS) who reported symptom onset after limb immobilization. Our objective was to investigate the association between trauma, immobilization and CBS. The charts of forty-four consecutive CBS patients seen in the Mayo Clinic Alzheimer Disease Research Center were reviewed with attention to trauma and limb immobilization. 10 CBS patients (23%) had immobilization or trauma on the most affected limb preceding the onset or acceleration of symptoms. The median age at onset was 61. Six patients manifested their first symptoms after immobilization from surgery or fracture with one after leg trauma. Four patients had pre-existing symptoms of limb dysfunction but significantly worsened after immobilization or surgery. 23 percent of patients had immobilization or trauma of the affected limb. This might have implications for management of CBS, for avoiding injury, limiting immobilization and increasing movement in the affected limb. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Quantification of apoptotic DNA fragmentation in a transformed uterine epithelial cell line, HRE-H9, using capillary electrophoresis with laser-induced fluorescence detector (CE-LIF).

    Science.gov (United States)

    Fiscus, R R; Leung, C P; Yuen, J P; Chan, H C

    2001-01-01

    Apoptotic cell death of uterine epithelial cells is thought to play an important role in the onset of menstruation and the successful implantation of an embryo during early pregnancy. Abnormal apoptosis in these cells can result in dysmenorrhoea and infertility. In addition, decreased rate of epithelial apoptosis likely contributes to endometriosis. A key step in the onset of apoptosis in these cells is cleavage of the genomic DNA between nucleosomes, resulting in polynucleosomal-sized fragments of DNA. The conventional technique for assessing apoptotic DNA fragmentation uses agarose (slab) gel electrophoresis (i.e. DNA laddering). However, recent technological advances in the use of capillary electrophoresis (CE), particularly the introduction of the laser-induced fluorescence detector (LIF), has made it possible to perform DNA laddering with improved automation and much greater sensitivity. In the present study, we have further developed the CE-LIF technique by using a DNA standard curve to quantify accurately the amount of DNA in the apoptotic DNA fragments and have applied this new quantitative technique to study apoptosis in a transformed uterine epithelial cell line, the HRE-H9 cells. Apoptosis was induced in the HRE-H9 cells by serum deprivation for 5, 7 and 24 h, resulting in increased DNA fragmentation of 2.2-, 3.1- and 6.2-fold, respectively, above the 0 h or plus-serum controls. This ultrasensitive CE-LIF technique provides a novel method for accurately measuring the actions of pro- or anti-apoptotic agents or conditions on uterine epithelial cell lines. Copyright 2001 Academic Press.

  8. In vivo biotinylation of recombinant beta-glucosidase enables simultaneous purification and immobilization on streptavidin coated magnetic particles

    DEFF Research Database (Denmark)

    Alftrén, Johan; Ottow, Kim Ekelund; Hobley, Timothy John

    2013-01-01

    Beta-glucosidase from Bacillus licheniformis was in vivo biotinylated in Escherichia coli and subsequently immobilized directly from cell lysate on streptavidin coated magnetic particles. In vivo biotinylation was mediated by fusing the Biotin Acceptor Peptide to the C-terminal of beta......-glucosidase and co-expressing the BirA biotin ligase. The approach enabled simultaneous purification and immobilization of the enzyme from crude cell lysate on magnetic particles because of the high affinity and strong interaction between biotin and streptavidin. After immobilization of the biotinylated beta...

  9. Status of plutonium ceramic immobilization processes and immobilization forms

    International Nuclear Information System (INIS)

    Ebbinghaus, B.B.; Van Konynenburg, R.A.; Vance, E.R.; Jostsons, A.

    1996-01-01

    Immobilization in a ceramic followed by permanent emplacement in a repository or borehole is one of the alternatives currently being considered by the Fissile Materials Disposition Program for the ultimate disposal of excess weapons-grade plutonium. To make Pu recovery more difficult, radioactive cesium may also be incorporated into the immobilization form. Valuable data are already available for ceramics form R ampersand D efforts to immobilize high-level and mixed wastes. Ceramics have a high capacity for actinides, cesium, and some neutron absorbers. A unique characteristic of ceramics is the existence of mineral analogues found in nature that have demonstrated actinide immobilization over geologic time periods. The ceramic form currently being considered for plutonium disposition is a synthetic rock (SYNROC) material composed primarily of zirconolite (CaZrTi 2 O 7 ), the desired actinide host phase, with lesser amounts of hollandite (BaAl 2 Ti 6 O 16 ) and rutile (TiO 2 ). Alternative actinide host phases are also being considered. These include pyrochlore (Gd 2 Ti 2 O 7 ), zircon (ZrSiO 4 ), and monazite (CePO 4 ), to name a few of the most promising. R ampersand D activities to address important technical issues are discussed. Primarily these include moderate scale hot press fabrications with plutonium, direct loading of PuO 2 powder, cold press and sinter fabrication methods, and immobilization form formulation issues

  10. Bioconversion of l-glutamic acid to α-ketoglutaric acid by an immobilized whole-cell biocatalyst expressing l-amino acid deaminase from Proteus mirabilis.

    Science.gov (United States)

    Hossain, Gazi Sakir; Li, Jianghua; Shin, Hyun-dong; Chen, Rachel R; Du, Guocheng; Liu, Long; Chen, Jian

    2014-01-01

    The goal of this work was to develop an immobilized whole-cell biocatalytic process for the environment-friendly synthesis of α-ketoglutaric acid (α-KG) from l-glutamic acid. We compared the suitability of Escherichia coli and Bacillus subtilis strains overexpressing Proteus mirabilisl-amino acid deaminase (l-AAD) as potential biocatalysts. Although both recombinant strains were biocatalytically active, the performance of B. subtilis was superior to that of E. coli. With l-glutamic acid as the substrate, α-KG production levels by membranes isolated from B. subtilis and E. coli were 55.3±1.73 and 21.7±0.39μg/mg protein/min, respectively. The maximal conversion ratio of l-glutamic acid to α-KG was 31% (w/w) under the following optimal conditions: 15g/L l-glutamic acid, 20g/L whole-cell biocatalyst, 5mM MgCl2, 40°C, pH 8.0, and 24-h incubation. Immobilization of whole cells with alginate increased the recyclability by an average of 23.33% per cycle. This work established an efficient one-step biotransformation process for the production of α-KG using immobilized whole B. subtilis overexpressing P. mirabilisl-AAD. Compared with traditional multistep chemical synthesis, the biocatalytic process described here has the advantage of reducing environmental pollution and thus has great potential for the large-scale production of α-KG. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Method for immobilizing particulate materials in a packed bed

    Science.gov (United States)

    Even, Jr., William R.; Guthrie, Stephen E.; Raber, Thomas N.; Wally, Karl; Whinnery, LeRoy L.; Zifer, Thomas

    1999-01-01

    The present invention pertains generally to immobilizing particulate matter contained in a "packed" bed reactor so as to prevent powder migration, compaction, coalescence, or the like. More specifically, this invention relates to a technique for immobilizing particulate materials using a microporous foam-like polymer such that a) the particulate retains its essential chemical nature, b) the local movement of the particulate particles is not unduly restricted, c) bulk powder migration and is prevented, d) physical and chemical access to the particulate is unchanged over time, and e) very high particulate densities are achieved. The immobilized bed of the present invention comprises a vessel for holding particulate matter, inlet and an outlet ports or fittings, a loosely packed bed of particulate material contained within the vessel, and a three dimensional porous matrix for surrounding and confining the particles thereby fixing the movement of individual particle to a limited local position. The established matrix is composed of a series of cells or chambers comprising walls surrounding void space, each wall forming the wall of an adjacent cell; each wall containing many holes penetrating through the wall yielding an overall porous structure and allowing useful levels of gas transport.

  12. Chromatin structure influence of DNA damage measurements by four assays: pulsed- and constant-field gel electrophoresis, DNA precipitation and non-denaturing filter elution

    International Nuclear Information System (INIS)

    Wlodek, D.; Olive, P.L.

    1996-01-01

    The of elution of DNA during non-denaturing filter elution (NFE) often correlates with cell sensitivity to radiation. The elution rate is influenced by two cellular factors: chromatin structure and the number of DNA-strand breaks (DSBs) produced in an intact cell by ionizing radiation. To determine which of the above factors is relevant to cell radiosensitivity, four assays were used to measure induction of DNA damage in three cell lines varying in radiosensitivity (V79, CHO, and L5178Y-R). Each of the assays, neutral filter elution (NFE), DNA precipitation, constant (CFGE) and pulsed field gel electrophoresis (PFGE) have different physical basis for DNA damage measurement and might be differently affected by chromatin structure. Three of the methods used to measure DNA double-strand breaks gave different results: NFE was dependent on cell type and location of DNA relative to the replication fork, gel electrophoresis was independent of cell type but was affected by proximity to the replication fork, and the precipitation assay was independent of both cell type and replication status. Pulsed field gel electrophoresis produced the same results and constant field gel electrophoresis for 3 cell lines examined. Only NFE showed differences in sensitivity which correlated with cell survival following irradiation. The results suggest that three is the same initial amount of DSBs in cells from all three lines and that the sensitivity to radiation is determined by some additional factors, probably chromatin structure. (author). 18 refs, 5 figs

  13. Proteomic analysis of docetaxel resistance in human nasopharyngeal carcinoma cells using the two-dimensional gel electrophoresis method.

    Science.gov (United States)

    Peng, Xingchen; Gong, Fengming M; Ren, Min; Ai, Ping; Wu, ShaoYong; Tang, Jie; Hu, XiaoLin

    2016-09-01

    Docetaxel-based chemotherapy has been recommended for advanced nasopharyngeal carcinoma (NPC). However, treatment failure often occurs because of acquired drug resistance. In this study, a docetaxel-resistant NPC cell line CNE-2R was established with increasing doses of docetaxel for more than 6 months. Two-dimensional gel electrophoresis and ESI-Q-TOF-MS were used to compare the differential expression of docetaxel-resistance-associated proteins between human NPC CNE-2 cells and docetaxel-resistant CNE-2R cells. As a result, 24 differentially expressed proteins were identified, including 11 proteins with increased expression and 13 proteins with decreased expression. These proteins function in diverse biological processes such as metabolism, signal transduction, calcium ion binding, immune response, proteolysis, and so on. Among these, α-enolase (ENO1), significantly upregulated in CNE-2R, was selected for detailed analysis. Inhibition of ENO1 by shRNA restored CNE-2R cells' sensitivity to docetaxel. Moreover, overexpression of ENO1 could facilitate the development of acquired resistance of docetaxel in CNE-2 cells. Western blot and reverse-transcription PCR data of clinical samples confirmed that α-enolase was upregulated in docetaxel-resistant human NPC tissues. Finding such proteins might improve interpretation of the molecular mechanisms leading to the acquisition of docetaxel chemoresistance.

  14. Processing of influenza HA protein in MDCK cells: components with different mobilities in polyacrylamide gel electrophoresis and their precursor-product relationships

    International Nuclear Information System (INIS)

    Sklyanskaya, E.I.; Rudneva, I.A.; Vovk, T.S.; Kaverin, N.V.

    1980-01-01

    In influenza virus-infected MDCK cells labelled with 14 C-chlorella hydrolysate or 35 S-methionine a virus-specific protein component is revealed migrating slightly faster than HA protein in polyacrylamide gel electrophoresis. Under chase conditions the component disappears either completely or partially, with a concomitant intensification of the HA band. The rate and extent of this transition are strain-dependent. Both the HA band and the faster moving component are not revealed if the cells are labelled in the presence of 20 mM of D-glucosamine. In primary cell cultures of chick embryos a single HA band with a mobility similar to that of the faster moving component in MDCK cells has been observed. It is suggested that the transition of the label from the faster moving component to the HA band reflects the final step of HA processing specific for MDCK cells. (author)

  15. Sodium thiosulphate induced immobilized bacterial disintegration of sludge: An energy efficient and cost effective platform for sludge management and biomethanation.

    Science.gov (United States)

    Ushani, U; Kavitha, S; Yukesh Kannah, R; Gunasekaran, M; Kumar, Gopalakrishnan; Nguyen, Dinh Duc; Chang, Soon Woong; Rajesh Banu, J

    2018-07-01

    The present study aimed to gain better insights into profitable biomethanation through sodium thiosulphate induced immobilized protease secreting bacterial disintegration (STS-IPBD) of sludge. STS disperse the flocs at 0.08 g/g SS of dosage and assists the subsequent bacterial disintegration. Immobilization of bacteria increases the hydrolytic activity of cells towards effective liquefaction of sludge. A higher liquefaction of 22% was accomplished for STS-IPBD when compared to immobilized protease secreting bacterial disintegration (IPBD alone). The kinetic parameters of Line Weaver Burk plot analysis revealed a maximal specific growth rate (µmax) of 0.320 h -1 for immobilized cells when compared to suspended free cells showing the benefit of immobilization. Floc dispersion and immobilization of bacteria imparts a major role in biomethanation as the methane generation (0.32 gCOD/g COD) was higher in STS-IPBD sample. The cost analysis showed that STS - IPBD was a feasible process with net profit of 2.6 USD/Ton of sludge. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Multiplexed Western Blotting Using Microchip Electrophoresis.

    Science.gov (United States)

    Jin, Shi; Furtaw, Michael D; Chen, Huaxian; Lamb, Don T; Ferguson, Stephen A; Arvin, Natalie E; Dawod, Mohamed; Kennedy, Robert T

    2016-07-05

    Western blotting is a commonly used protein assay that combines the selectivity of electrophoretic separation and immunoassay. The technique is limited by long time, manual operation with mediocre reproducibility, and large sample consumption, typically 10-20 μg per assay. Western blots are also usually used to measure only one protein per assay with an additional housekeeping protein for normalization. Measurement of multiple proteins is possible; however, it requires stripping membranes of antibody and then reprobing with a second antibody. Miniaturized alternatives to Western blot based on microfluidic or capillary electrophoresis have been developed that enable higher-throughput, automation, and greater mass sensitivity. In one approach, proteins are separated by electrophoresis on a microchip that is dragged along a polyvinylidene fluoride membrane so that as proteins exit the chip they are captured on the membrane for immunoassay. In this work, we improve this method to allow multiplexed protein detection. Multiple injections made from the same sample can be deposited in separate tracks so that each is probed with a different antibody. To further enhance multiplexing capability, the electrophoresis channel dimensions were optimized for resolution while keeping separation and blotting times to less than 8 min. Using a 15 μm deep × 50 μm wide × 8.6 cm long channel, it is possible to achieve baseline resolution of proteins that differ by 5% in molecular weight, e.g., ERK1 (44 kDa) from ERK2 (42 kDa). This resolution allows similar proteins detected by cross-reactive antibodies in a single track. We demonstrate detection of 11 proteins from 9 injections from a single Jurkat cell lysate sample consisting of 400 ng of total protein using this procedure. Thus, multiplexed Western blots are possible without cumbersome stripping and reprobing steps.

  17. Mapping and identification of HeLa cell proteins separated by immobilized pH-gradient two-dimensional gel electrophoresis and construction of a two-dimensional polyacrylamide gel electrophoresis database

    DEFF Research Database (Denmark)

    Shaw, AC; Rossel Larsen, M; Roepstorff, P

    1999-01-01

    The HeLa cell line, a human adenocarcinoma, is used in many research fields, since it can be infected with a wide range of viruses and intracellular bacteria. Therefore, the mapping of HeLa cell proteins is useful for the investigation of parasite host cell interactions. Because of the recent imp...... these and future data accessible for interlaboratory comparison, we constructed a 2-D PAGE database on the World Wide Web....... the mapping of [35S]methionine/cysteine-labeled HeLa cell proteins with the 2-D PAGE (IPG)-system, using matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) and N-terminal sequencing for protein identification. To date 21 proteins have been identified and mapped. In order to make...

  18. Immobilization of Trichoderma reesei by radiation polymerization

    International Nuclear Information System (INIS)

    Zhou Ruimin; Ma Zueteh; Kaetus, Isao; Kumakura, Minoro

    1993-01-01

    Immobilization of Trichoderma reesei was carried out by radiation polymerization. It was found that the activity of fixed cells increased with increasing surface area of the carrier and was affected by the concentration of monomer tetraethylenglycol dimethacrylate and the shape of the substrate composition and structure of cotton textile fabrics. (author)

  19. Degradation of phenol and TCE using suspended and chitosan-bead immobilized Pseudomonas putida.

    Science.gov (United States)

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

    2007-09-30

    The degradability of phenol and trichloroethene (TCE) by Pseudomonas putida BCRC 14349 in both suspended culture and immobilized culture systems are investigated. Chitosan beads at a size of about 1-2mm were employed to encapsulate the P. putida cells, becoming an immobilized culture system. The phenol concentration was controlled at 100 mg/L, and that of TCE was studied from 0.2 to 20 mg/L. The pH, between 6.7 and 10, did not affect the degradation of either phenol or TCE in the suspended culture system. However, it was found to be an important factor in the immobilized culture system in which the only significant degradation was observed at pH >8. This may be linked to the surface properties of the chitosan beads and its influence on the activity of the bacteria. The transfer yield of TCE on a phenol basis was almost the same for the suspended and immobilized cultures (0.032 mg TCE/mg phenol), except that these yields occurred at different TCE concentrations. The transfer yield at a higher TCE concentration for the immobilized system suggested that the cells immobilized in carriers can be protected from harsh environmental conditions. For kinetic rate interpretation, the Monod equation was employed to describe the degradation rates of phenol, while the Haldane's equation was used for TCE degradation. Based on the kinetic parameters obtained from the two equations, the rate for the immobilized culture systems was only about 1/6 to that of the suspended culture system for phenol degradation, and was about 1/2 for TCE degradation. The slower kinetics observed for the immobilized culture systems was probably due to the slow diffusion of substrate molecules into the beads. However, compared with the suspended cultures, the immobilized cultures may tolerate a higher TCE concentration as much less inhibition was observed and the transfer yield occurred at a higher TCE concentration.

  20. Status of plutonium ceramic immobilization processes and immobilization forms

    Energy Technology Data Exchange (ETDEWEB)

    Ebbinghaus, B.B.; Van Konynenburg, R.A. [Lawrence Livermore National Lab., CA (United States); Vance, E.R.; Jostsons, A. [Australian Nuclear Science and Technology Organization, Menai (Australia)] [and others

    1996-05-01

    Immobilization in a ceramic followed by permanent emplacement in a repository or borehole is one of the alternatives currently being considered by the Fissile Materials Disposition Program for the ultimate disposal of excess weapons-grade plutonium. To make Pu recovery more difficult, radioactive cesium may also be incorporated into the immobilization form. Valuable data are already available for ceramics form R&D efforts to immobilize high-level and mixed wastes. Ceramics have a high capacity for actinides, cesium, and some neutron absorbers. A unique characteristic of ceramics is the existence of mineral analogues found in nature that have demonstrated actinide immobilization over geologic time periods. The ceramic form currently being considered for plutonium disposition is a synthetic rock (SYNROC) material composed primarily of zirconolite (CaZrTi{sub 2}O{sub 7}), the desired actinide host phase, with lesser amounts of hollandite (BaAl{sub 2}Ti{sub 6}O{sub 16}) and rutile (TiO{sub 2}). Alternative actinide host phases are also being considered. These include pyrochlore (Gd{sub 2}Ti{sub 2}O{sub 7}), zircon (ZrSiO{sub 4}), and monazite (CePO{sub 4}), to name a few of the most promising. R&D activities to address important technical issues are discussed. Primarily these include moderate scale hot press fabrications with plutonium, direct loading of PuO{sub 2} powder, cold press and sinter fabrication methods, and immobilization form formulation issues.

  1. Hyaluronan Immobilized Polyurethane as a Blood Contacting Material

    Directory of Open Access Journals (Sweden)

    Feirong Gong

    2010-01-01

    Full Text Available Hyaluronan (hyaluronic acid, HA was immobilized onto the surface of amino-functionalized polyurethane films with the goal of obtaining a novel kind of biomaterial which had the potential in blood-contacting applications. The amino-functionalized polyurethane was prepared by synthesized acidic polyurethane whose pendant carboxyl groups were treated with an excess amount of 1,3-diaminopropane in the presence of N,N-carbonyldiimidazole (CDI. Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR, Raman spectroscopy (RS, scanning electron microscopy (SEM, and water contact angle measurement were used to confirm the surface changes at each step of treatment, both in morphologies and chemical compositions. APTT and PT results showed that HA immobilization could prolong the blood coagulation time, thus HA-immobilized polyurethane (PU-HA exhibited improved blood compatibility. Cytotoxicity analysis showed that the PU-HA films synthesized in this study were cytocompatible and could support human vein endothelial cells (HUVECs adhesion and proliferation.

  2. Immobilization of epidermal growth factor on titanium and stainless steel surfaces via dopamine treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Jeonghwa [Nano Medical Engineering Laboratory, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-Osawa, Tokyo, 192-0397 Japan (Japan); Sakuragi, Makoto; Shibata, Aya; Abe, Hiroshi; Kitajima, Takashi; Tada, Seiichi [Nano Medical Engineering Laboratory, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Mizutani, Masayoshi; Ohmori, Hitoshi [Material Fabrication Laboratory, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Ayame, Hirohito [Diagnostic Biochip Laboratory, RIKEN Center for Intellectual Property Strategies, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Son, Tae Il [Bioscience and Biotechnology, Chung-Ang University, 40-1 San, Nae-Ri, Daeduck-myun, Ansung-si, Kyungki-do, 456-756 (Korea, Republic of); Aigaki, Toshiro [Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-Osawa, Tokyo, 192-0397 Japan (Japan); Ito, Yoshihiro, E-mail: y-ito@riken.jp [Nano Medical Engineering Laboratory, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-Osawa, Tokyo, 192-0397 Japan (Japan); Diagnostic Biochip Laboratory, RIKEN Center for Intellectual Property Strategies, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan)

    2012-12-01

    Titanium and stainless steel were modified with dopamine for the immobilization of biomolecules, epidermal growth factor (EGF). First, the treatment of metal surfaces with a dopamine solution under different pH conditions was investigated. At higher pH, the dopamine solution turned brown and formed precipitates. Treatment of the metals with dopamine at pH 8.5 also resulted in the development of brown color at the surface of the metals. The hydrophobicity of the surfaces increased after treatment with dopamine, independently of pH. X-ray photoelectron spectroscopy revealed the formation of a significant amount of an organic layer on both surfaces at pH 8.5. According to ellipsometry measurements, the organic layer formed at pH 8.5 was about 1000 times as thick as that formed at pH 4.5. The amount of amino groups in the layer formed at pH 8.5 was also higher than that observed in the layer formed at pH 4.5. EGF molecules were immobilized onto the dopamine-treated surfaces via a coupling reaction using carbodiimide. A greater amount of EGF was immobilized on surfaces treated at pH 8.5 compared with pH 4.5. Significantly higher growth of rat fibroblast cells was observed on the two EGF-immobilized surfaces compared with non-immobilized surfaces in the presence of EGF. The present study demonstrated that metals can become bioactive via the surface immobilization of a growth factor and that the effect of the immobilized growth factor on metals was greater than that of soluble growth factor. - Highlights: Black-Right-Pointing-Pointer Epidermal growth factor was covalently immobilized on titan or stainless steel surfaces. Black-Right-Pointing-Pointer Amino groups were formed on the surfaces by the treatment and the growth factor was immobilized through amide bonds. Black-Right-Pointing-Pointer The immobilized epidermal growth factor accelerated cell proliferation more than soluble ones on the surfaces.

  3. Characterization of Seed Storage Proteins from Chickpea Using 2D Electrophoresis Coupled with Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Pramod Kumar Singh

    2016-01-01

    Full Text Available Proteomic analysis was employed to map the seed storage protein network in landrace and cultivated chickpea accessions. Protein extracts were separated by two-dimensional gel electrophoresis (2D-GE across a broad range 3.0–10.0 immobilized pH gradient (IPG strips. Comparative elucidation of differentially expressed proteins between two diverse geographically originated chickpea accessions was carried out using 2D-GE coupled with mass spectrometry. A total of 600 protein spots were detected in these accessions. In-gel protein expression patterns revealed three protein spots as upregulated and three other as downregulated. Using trypsin in-gel digestion, these differentially expressed proteins were identified by matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS which showed 45% amino acid homology of chickpea seed storage proteins with Arabidopsis thaliana.

  4. Analytical biotechnology: Capillary electrophoresis and chromatography

    International Nuclear Information System (INIS)

    Horvath, C.; Nikelly, J.G.

    1990-01-01

    The papers describe the separation, characterization, and equipment required for the electrophoresis or chromatography of cyclic nucleotides, pharmaceuticals, therapeutic proteins, recombinant DNA products, pheromones, peptides, and other biological materials. One paper, On-column radioisotope detection for capillary electrophoresis, has been indexed separately for inclusion on the data base

  5. Physical immobilization of biofunctional substance by the use of radiation polymerization

    International Nuclear Information System (INIS)

    Kobayashi, M.; Kaetsu, I.

    1982-01-01

    Radiation-induced polymerization at low temperatures of glass-forming monomers in a supercooled state can be applied, for example, in casting of organic glass and the immobilization of biofunctional substance. The immobilization of various biofunctional materials such as enzymes, microbial cells, tissue cells etc. will be a promising application in the near future in biotechnology and bioengineering. The authors studied the immobilization technique which can be applied to general biocomponents, by using low-temperature radiation polymerization in a supercooled phase. According to this method, biocomponents are composed mainly on the surface of the carrier polymer, and therefore the product has the bioactivity at the surface of the composite. This method can be called the adhesion method. Biocomponents can be composed simply by mixing with monomer, shaping into a desirable form, then cooling to low temperature and irradiating into a product. On the cooling of the monomer-buffer (including biocomponent) mixture, water in the buffer changes to ice and then the biocomponents in the buffer are isolated from the ice, and concentrated on a surface of supercooled monomer phase. These biocomponents are fixed immediately on the polymer surface by irradiation. Anti-cancers immobilized by low-temperature radiation-induced polymerization have been applied to local chemotherapy by implantation, and the result of such a slow release system has been proved to be successful by animal experiments. The application of the radiation immobilized antibody to immunoassay has also been proved successful. The authors started research on the utilization of radiation techniques for the conversion of cellulosic wastes such as chaff, rice straw, sawdust, bagasse and wastepaper. It includes pretreatment by irradiation of cellulose wastes and saccharification and fermentation by using radiation immobilized enzymes and yeasts. (author)

  6. Enzyme Immobilization: An Overview on Methods, Support Material, and Applications of Immobilized Enzymes.

    Science.gov (United States)

    Sirisha, V L; Jain, Ankita; Jain, Amita

    Immobilized enzymes can be used in a wide range of processes. In recent years, a variety of new approaches have emerged for the immobilization of enzymes that have greater efficiency and wider usage. During the course of the last two decades, this area has rapidly expanded into a multidisciplinary field. This current study is a comprehensive review of a variety of literature produced on the different enzymes that have been immobilized on various supporting materials. These immobilized enzymes have a wide range of applications. These include applications in the sugar, fish, and wine industries, where they are used for removing organic compounds from waste water. This study also reviews their use in sophisticated biosensors for metabolite control and in situ measurements of environmental pollutants. Immobilized enzymes also find significant application in drug metabolism, biodiesel and antibiotic production, bioremediation, and the food industry. The widespread usage of immobilized enzymes is largely due to the fact that they are cheaper, environment friendly, and much easier to use when compared to equivalent technologies. © 2016 Elsevier Inc. All rights reserved.

  7. Assessing attitudes toward spinal immobilization.

    Science.gov (United States)

    Bouland, Andrew J; Jenkins, J Lee; Levy, Matthew J

    2013-10-01

    Prospective studies have improved knowledge of prehospital spinal immobilization. The opinion of Emergency Medical Services (EMS) providers regarding spinal immobilization is unknown, as is their knowledge of recent research advances. To examine the attitudes, knowledge, and comfort of prehospital and Emergency Department (ED) EMS providers regarding spinal immobilization performed under a non-selective protocol. An online survey was conducted from May to July of 2011. Participants were drawn from the Howard County Department of Fire and Rescue Services and the Howard County General Hospital ED. The survey included multiple choice questions and responses on a modified Likert scale. Correlation analysis and descriptive data were used to analyze results. Comfort using the Kendrick Extrication Device was low among ED providers. Experienced providers were more likely to indicate comfort using this device. Respondents often believed that spinal immobilization is appropriate in the management of penetrating trauma to the chest and abdomen. Reported use of padding decreased along with the frequency with which providers practice and encounter immobilized patients. Respondents often indicated that they perform spinal immobilization due solely to mechanism of injury. Providers who feel as if spinal immobilization is often performed unnecessarily were more likely to agree that immobilization causes an unnecessary delay in patient care. The results demonstrate the need for improved EMS education in the use of the Kendrick Extrication Device, backboard padding, and spinal immobilization in the management of penetrating trauma. The attitudes highlighted in this study are relevant to the implementation of a selective spinal immobilization protocol. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Assessment of DNA damage in radiation workers by using single cell gel electrophoresis

    International Nuclear Information System (INIS)

    Jia Lili; Zhang Tao; Yang Yonghua; Wang Yan; Du Liqing; Cao Jia; Wang Hong; Liu Qiang; Fan Feiyue

    2010-01-01

    Objective: To assess the DNA damage of radiation workers in different grade hospitals, and to explore the correlation between the types of work or work time and the levels of DNA damage. Methods: DNA single strand break were detected by using alkaline single cell gel electrophoresis (SCGE), and the comet was analyzed with CASP (Comet Assay Software Project). TDNA%, TL, TM and OTM were calculated. Results: The parameters of SCGE in the radiation group were higher than those of control group (F=3.93, P<0.01). The significant difference was found not only among the different types of work or different work time, but also among the different grade hospitals (F=1.83, 1.91, P<0.05). Conclusions: Various levels of DNA damage could be detected in the radiation workers of the two hospitals. DNA damage of radiation workers is less serious in the higher-grade hospital than the lower grade one. Different types of work or work time might affect the DNA damage level. (authors)

  9. Silk fibroin immobilization on poly(ethylene terephthalate) films: Comparison of two surface modification methods and their effect on mesenchymal stem cells culture

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Meini; Yao, Jinrong; Chen, Xin; Huang, Lei; Shao, Zhengzhong, E-mail: zzshao@fudan.edu.cn

    2013-04-01

    Silk fibroin (SF) has played a curial role for the surface modification of conventional materials to improve the biocompatibility, and SF modified poly(ethylene terephthalate) (PET) materials have potential applications on tissue engineering such as artificial ligament, artificial vessel, artificial heart valve sewing cuffs dacron and surgical mesh engineering. In this work, SF was immobilized onto PET film via two different methods: 1) plasma pretreatment followed by SF dip coating (PET-SF) and 2) plasma-induce acrylic acid graft polymerization and subsequent covalent immobilization of SF on PET film (PET-PAA-SF). It could be found that plasma treatment provided higher surface roughness which was suitable for further SF dip coating, while grafted poly(acrylic acid) (PAA) promised the covalent bonding between SF and PAA. ATR-FTIR adsorption band at 3284 cm{sup −1}, 1623 cm{sup −1} and 1520 cm{sup −1} suggested the successful introduction of SF onto PET surface, while the amount of immobilized SF of PET-SF was higher than PET-PAA-SF according to XPS investigation (0.29 vs 0.23 for N/C ratio). Surface modified PET film was used as substrate for mesenchymal stem cells (MSCs) culture, the cells on PET-SF surface exhibited optimum density compared to PET-PAA-SF according to CCK-8 assays, which indicated that plasma pretreatment followed by SF dip coating was a simple and effective way to prepare biocompatible PET surface. Highlights: ► Silk fibroins were immobilized onto PET films with or without the linker of PAA. ► Various techniques were performed to characterize the modified surfaces ► Plasma treatment followed by SF dip coating introduced more SF onto PET films. ► Compare to PET-PAA-SF, PET-SF has better biocompatibility base on MSCs culture.

  10. Fast methods for analysis of neurotransmitters from single cell and monitoring their releases in central nervous system by capillary electrophoresis, fluorescence microscopy and luminescence imaging

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ziqiang [Iowa State Univ., Ames, IA (United States)

    1999-12-10

    Fast methods for separation and detection of important neurotransmitters and the releases in central nervous system (CNS) were developed. Enzyme based immunoassay combined with capillary electrophoresis was used to analyze the contents of amino acid neurotransmitters from single neuron cells. The release of amino acid neurotransmitters from neuron cultures was monitored by laser induced fluorescence imaging method. The release and signal transduction of adenosine triphosphate (ATP) in CNS was studied with sensitive luminescence imaging method. A new dual-enzyme on-column reaction method combined with capillary electrophoresis has been developed for determining the glutamate content in single cells. Detection was based on monitoring the laser-induced fluorescence of the reaction product NADH, and the measured fluorescence intensity was related to the concentration of glutamate in each cell. The detection limit of glutamate is down to 10-8 M level, which is 1 order of magnitude lower than the previously reported detection limit based on similar detection methods. The mass detection limit of a few attomoles is far superior to that of any other reports. Selectivity for glutamate is excellent over most of amino acids. The glutamate content in single human erythrocyte and baby rat brain neurons were determined with this method and results agreed well with literature values.

  11. Acceleration of vertical migration of corneal epithelial cells in albino rats during chronic immobilization stress

    International Nuclear Information System (INIS)

    Timoshin, S.S.; Berezhnova, N.I.

    1986-01-01

    This paper studies the effect of chronic immobilization stress on the kinetics of corneal epithelial cells from the basal layer into higher layers. Experiments were carried out on 49 male rats. The animals were given an intraperitoneal injection of tritium-thymidine and an additional application of 5 microCi of tritium-thymidine was made to its surface because the cornea has no blood supply. The animals were killed and the cornea removed for investigation. Values of the index of labeled nuclei and intensity of thymidine labeling, characterizing DNA synthesis in the corneas of the control and experimental animals showed no significant change compared with their values in a pervious series of experiments. Chronic exposure to stress increased the velocity of vertical migration of the cells from the basal layer toward the outer layers of the cornea

  12. Agarose gel electrophoresis and polyacrylamide gel electrophoresis for visualization of simple sequence repeats.

    Science.gov (United States)

    Anderson, James; Wright, Drew; Meksem, Khalid

    2013-01-01

    In the modern age of genetic research there is a constant search for ways to improve the efficiency of plant selection. The most recent technology that can result in a highly efficient means of selection and still be done at a low cost is through plant selection directed by simple sequence repeats (SSRs or microsatellites). The molecular markers are used to select for certain desirable plant traits without relying on ambiguous phenotypic data. The best way to detect these is the use of gel electrophoresis. Gel electrophoresis is a common technique in laboratory settings which is used to separate deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) by size. Loading DNA and RNA onto gels allows for visualization of the size of fragments through the separation of DNA and RNA fragments. This is achieved through the use of the charge in the particles. As the fragments separate, they form into distinct bands at set sizes. We describe the ability to visualize SSRs on slab gels of agarose and polyacrylamide gel electrophoresis.

  13. Capillary zone electrophoresis-multiple reaction monitoring from 100 pg of RAW 264.7 cell lysate digest.

    Science.gov (United States)

    Sun, Liangliang; Li, Yihan; Champion, Matthew M; Zhu, Guijie; Wojcik, Roza; Dovichi, Norman J

    2013-06-07

    Capillary zone electrophoresis-multiple/single reaction monitoring (CZE-MRM/SRM), which employed an electrokinetically driven sheath-flow electrospray interface, was used for the rapid and highly sensitive detection of protein analytes in complex tryptic digests. MRM channels were developed against a commercial exponential mixture of bovine proteins. Five proteins spanning four orders of magnitude concentration range were confidently detected from only 2.5 ng of the digest mixture; the mass detection limits (S/N = 3) of two detected proteins, alpha-casein and glutamate dehydrogenase were about 600 zmol and 30 amol, respectively. This technique was then applied to a RAW 264.7 cell lysate digest. Three proteins were confidently and reproducibly detected from 100 pg of this digest. The sample amount corresponds to the approximate protein content from a single cell, which suggests that CZE-MRM may be a useful analytical tool in chemical cytometry. In addition to providing highly sensitive detection of proteins in complex mixtures, this system is highly rapid; migration time of the protein digests was less than 10 min.

  14. Layer-by-layer immobilized catalase on electrospun nanofibrous mats protects against oxidative stress induced by hydrogen peroxide.

    Science.gov (United States)

    Huang, Rong; Deng, Hongbing; Cai, Tongjian; Zhan, Yingfei; Wang, Xiankai; Chen, Xuanxuan; Ji, Ailing; Lil, Xueyong

    2014-07-01

    Catalase, a kind of redox enzyme and generally recognized as an efficient agent for protecting cells against hydrogen peroxide (H2O2)-induced cytotoxicity. The immobilization of catalase was accomplished by depositing the positively charged chitosan and the negatively charged catalase on electrospun cellulose nanofibrous mats through electrospining and layer-by-layer (LBL) techniques. The morphology obtained from Field emission scanning electron microscopy (FE-SEM) indicated that more orderly arranged three-dimension (3D) structure and roughness formed with increasing the number of coating bilayers. Besides, the enzyme-immobilized nanofibrous mats were found with high enzyme loading and activity, moreover, X-ray photoelectron spectroscopy (XPS) results further demonstrated the successful immobilization of chitosan and catalase on cellulose nanofibers support. Furthermore, we evaluated the cytotoxicity induced by hydrogen peroxide in the Human umbilical vascular endothelial cells with or without pretreatment of nanofibrous mats by MTT assay, LDH activity and Flow cytometric evaluation, and confirmed the pronounced hydrogen peroxide-induced toxicity, but pretreatment of immobilized catalase reduced the cytotoxicity and protected cells against hydrogen peroxide-induced cytotoxic effects which were further demonstrated by scanning electron microscopy (SEM) and Transmission Electron Microscopy (TEM) images. The data pointed toward a role of catalase-immobilized nanofibrous mats in protecting cells against hydrogen peroxide-induced cellular damage and their potential application in biomedical field.

  15. Immobilization of cellulase by radiation polymerization

    International Nuclear Information System (INIS)

    Kumakura, M.; Kaetsu, I.

    1983-01-01

    Immobilization of cellulase by radiation polymerization at low temperatures was studied. The enzymatic activity of immobilized cellulase pellets varied with the monomer, enzyme concentration, and the thickness of immobilized cellulase pellets. The optimum monomer concentration in the immobilization of cellulase was 30-50% at the pellet thickness of 1.0 mm, in which the enzymatic activity was 50%. The enzymatic activity of immobilized cellulase pellets was examined using various substrates such as cellobiose, carboxymethylcellulose, and paper pretreated by radiation. It was found that irradiated paper can be hydrolyzed by immobilized cellulase pellets. (author)

  16. The removal of thermo-tolerant coliform bacteria by immobilized waste stabilization pond algae.

    Science.gov (United States)

    Pearson, H W; Marcon, A E; Melo, H N

    2011-01-01

    This study investigated the potential of laboratory- scale columns of immobilized micro-algae to disinfect effluents using thermo-tolerant coliforms (TTC) as a model system. Cells of a Chlorella species isolated from a waste stabilization pond complex in Northeast Brazil were immobilized in calcium alginate, packed into glass columns and incubated in contact with TTC suspensions for up to 24 hours. Five to six log removals of TTC were achieved in 6 hours and 11 log removals in 12 hours contact time. The results were similar under artificial light and shaded sunlight. However little or no TTC removal occurred in the light in columns of alginate beads without immobilized algae present or when the immobilized algae were incubated in the dark suggesting that the presence of both algae and light were necessary for TTC decay. There was a positive correlation between K(b) values for TTC and increasing pH in the effluent from the immobilized algal columns within the range pH 7.2 and 8.9. The potential of immobilized algal technology for wastewater disinfection may warrant further investigation.

  17. RAD18 and associated proteins are immobilized in nuclear foci in human cells entering S-phase with ultraviolet light-induced damage

    International Nuclear Information System (INIS)

    Watson, Nicholas B.; Nelson, Eric; Digman, Michelle; Thornburg, Joshua A.; Alphenaar, Bruce W.; McGregor, W. Glenn

    2008-01-01

    Proteins required for translesion DNA synthesis localize in nuclear foci of cells with replication-blocking lesions. The dynamics of this process were examined in human cells with fluorescence-based biophysical techniques. Photobleaching recovery and raster image correlation spectroscopy experiments indicated that involvement in the nuclear foci reduced the movement of RAD18 from diffusion-controlled to virtual immobility. Examination of the mobility of REV1 indicated that it is similarly immobilized when it is observed in nuclear foci. Reducing the level of RAD18 greatly reduced the focal accumulation of REV1 and reduced UV mutagenesis to background frequencies. Fluorescence lifetime measurements indicated that RAD18 and RAD6A or polη only transferred resonance energy when these proteins colocalized in damage-induced nuclear foci, indicating a close physical association only within such foci. Our data support a model in which RAD18 within damage-induced nuclear foci is immobilized and is required for recruitment of Y-family DNA polymerases and subsequent mutagenesis. In the absence of damage these proteins are not physically associated within the nucleoplasm

  18. Electrical conductivity measurements of aqueous and immobilized potassium hydroxide

    DEFF Research Database (Denmark)

    Allebrod, Frank; Chatzichristodoulou, Christodoulos; Mollerup, Pia Lolk

    2012-01-01

    concentrations was investigated using the van der Pauw method in combination with electrochemical impedance spectroscopy (EIS). Conductivity values as high as 2.7 S cm−1 for 35 wt%, 2.9 S cm−1 for 45 wt%, and 2.8 S cm−1 for 55 wt% concentrated aqueous solutions were measured at 200 °C. Micro- and nano-porous...... solid pellets were produced and used to immobilize aqueous KOH solutions. These are intended to operate as ion-conductive diaphragms (electrolytes) in alkaline electrolysis cells, offering high conductivity and corrosion resistance. The conductivity of immobilized KOH has been determined by the same...

  19. Blood grouping based on PCR methods and agarose gel electrophoresis.

    Science.gov (United States)

    Sell, Ana Maria; Visentainer, Jeane Eliete Laguila

    2015-01-01

    The study of erythrocyte antigens continues to be an intense field of research, particularly after the development of molecular testing methods. More than 300 specificities have been described by the International Society for Blood Transfusion as belonging to 33 blood group systems. The polymerase chain reaction (PCR) is a central tool for red blood cells (RBC) genotyping. PCR and agarose gel electrophoresis are low cost, easy, and versatile in vitro methods for amplifying defined target DNA (RBC polymorphic region). Multiplex-PCR, AS-PCR (Specific Allele Polymerase Chain Reaction), and RFLP-PCR (Restriction Fragment Length Polymorphism-Polymerase Chain Reaction) techniques are usually to identify RBC polymorphisms. Furthermore, it is an easy methodology to implement. This chapter describes the PCR methodology and agarose gel electrophoresis to identify the polymorphisms of the Kell, Duffy, Kidd, and MNS blood group systems.

  20. Immobilized waste leaching

    International Nuclear Information System (INIS)

    Suarez, A.A.

    1989-01-01

    The main mechanism by which the immobilized radioactive materials can return to biosphere is the leaching due to the intrusion of water into the repositories. Some mathematical models and experiments utilized to evaluate the leaching rates in different immobilization matrices are described. (author) [pt

  1. d-Tagatose production by permeabilized and immobilized Lactobacillus plantarum using whey permeate.

    Science.gov (United States)

    Jayamuthunagai, J; Srisowmeya, G; Chakravarthy, M; Gautam, P

    2017-07-01

    The aim of the work is to produce d-Tagatose by direct addition of alginate immobilized Lactobacillus plantarum cells to lactose hydrolysed whey permeate. The cells were untreated and immobilized (UIC), permeabilized and immobilized (PIC) and the relative activities were compared with purified l-arabinose isomerase (l-AI) for d-galactose isomerization. Successive lactose hydrolysis by β-galactosidase from Escherichia coli and d-galactose isomerization using l-AI from Lactobacillus plantarum was performed to investigate the in vivo production of d-tagatose in whey permeate. In whey permeate, maximum conversion of 38% and 33% (w/w) d-galactose isomerization by PIC and UIC has been obtained. 162mg/g and 141mg/g of d-tagatose production was recorded in a 48h reaction time at 50°C, pH 7.0 with 5mM Mn 2+ ion concentration in the initial substrate mixture. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Plutonium Disposition by Immobilization

    International Nuclear Information System (INIS)

    Gould, T.; DiSabatino, A.; Mitchell, M.

    2000-01-01

    The ultimate goal of the Department of Energy (DOE) Immobilization Project is to develop, construct, and operate facilities that will immobilize between 17 to 50 tonnes (MT) of U.S. surplus weapons-usable plutonium materials in waste forms that meet the ''spent fuel'' standard and are acceptable for disposal in a geologic repository. Using the ceramic can-in-canister technology selected for immobilization, surplus plutonium materials will be chemically combined into ceramic forms which will be encapsulated within large canisters of high level waste (HLW) glass. Deployment of the immobilization capability should occur by 2008 and be completed within 10 years. In support of this goal, the DOE Office of Fissile Materials Disposition (MD) is conducting development and testing (D and T) activities at four DOE laboratories under the technical leadership of Lawrence Livermore National Laboratory (LLNL). The Savannah River Site has been selected as the site for the planned Plutonium Immobilization Plant (PIP). The D and T effort, now in its third year, will establish the technical bases for the design, construction, and operation of the U. S. capability to immobilize surplus plutonium in a suitable and cost-effective manner. Based on the D and T effort and on the development of a conceptual design of the PIP, automation is expected to play a key role in the design and operation of the Immobilization Plant. Automation and remote handling are needed to achieve required dose reduction and to enhance operational efficiency

  3. Proteomic analysis of differential protein expression of achilles tendon in a rabbit model by two-dimensional polyacrylamide gel electrophoresis at 21 days postoperation.

    Science.gov (United States)

    Jielile, Jiasharete; Jialili, Ainuer; Sabirhazi, Gulnur; Shawutali, Nuerai; Redati, Darebai; Chen, Jiangtao; Tang, Bin; Bai, Jingping; Aldyarhan, Kayrat

    2011-10-01

    Postoperative early kinesitherapy has been advocated as an optimal method for treating Achilles tendon rupture. However, an insight into the rationale of how early kinesitherapy contributes to healing of Achilles tendon remains to be achieved, and research in the area of proteomic analysis of Achilles tendon has so far been lacking. Forty-two rabbits were randomized into control group, immobilization group, and early motion group, and received postoperative cast immobilization and early motion treatments. Achilles tendon samples were prepared 21 days following microsurgery, and the proteins were separated with two-dimensional polyacrylamide gel electrophoresis. Differentially expressed proteins were first recognized by PDQuest software, and then identified using peptide mass fingerprinting, tandem mass spectrometry, and database searching. A total of 463  ±  12, 511  ±  39, and 513  ±  80 protein spots were successfully detected in the two-dimensional polyacrylamide gels for the Achilles tendon samples of rabbits in the control group, immobilization group, and early motion group, respectively. There were 15, 8, and 9 unique proteins in these three groups, respectively, and some differentially expressed proteins were also identified in each group. It was indicated that some of the differentially expressed proteins were involved in various metabolism pathways and may play an important role in healing of Achilles tendon rupture. Postoperative early kinesitherapy resulted in differentially expressed proteins in ruptured Achilles tendon compared with those treated with postoperative cast immobilization. These differentially expressed proteins may contribute to healing of Achilles tendon rupture through a mechanobiological mechanism due to the application of postoperative early kinesitherapy.

  4. Protein electrophoresis - serum

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003540.htm Protein electrophoresis - serum To use the sharing features on ... JavaScript. This lab test measures the types of protein in the fluid (serum) part of a blood ...

  5. Immobilization of microbial cells: A promising tool for treatment of ...

    African Journals Online (AJOL)

    Suzana

    2013-07-10

    Jul 10, 2013 ... (zeolite, clay, anthracite, porous glass, activated char- coal, and ceramics) and organic polymers. Inorganic carriers were selected to immobilize microorganisms because they can resist microbial degradation and are thermostable (Cassidy et al., 1996; Verma et al., 2006). The organic polymeric carriers are ...

  6. Phylogenetic reconstruction of South American felids defined by protein electrophoresis.

    Science.gov (United States)

    Slattery, J P; Johnson, W E; Goldman, D; O'Brien, S J

    1994-09-01

    Phylogenetic associations among six closely related South American felid species were defined by changes in protein-encoding gene loci. We analyzed proteins isolated from skin fibroblasts using two-dimensional electrophoresis and allozymes extracted from blood cells. Genotypes were determined for multiple individuals of ocelot, margay, tigrina, Geoffroy's cat, kodkod, and pampas cat at 548 loci resolved by two-dimensional electrophoresis and 44 allozyme loci. Phenograms were constructed using the methods of Fitch-Margoliash and neighbor-joining on a matrix of Nei's unbiased genetic distances for all pairs of species. Results of a relative-rate test indicate changes in two-dimensional electrophoresis data are constant among all South American felids with respect to a hyena outgroup. Allelic frequencies were transformed to discrete character states for maximum parsimony analysis. Phylogenetic reconstruction indicates a major split occurred approximately 5-6 million years ago, leading to three groups within the ocelot lineage. The earliest divergence led to Leopardus tigrina, followed by a split between an ancestor of an unresolved trichotomy of three species (Oncifelis guigna, O. geoffroyi, and Lynchailuris colocolo) and a recent common ancestor of Leopardus pardalis and L. wiedii. The results suggest that modern South American felids are monophyletic and evolved rapidly after the formation of the Panama land bridge between North and South America.

  7. Response surface optimization for the transesterification of karanja oil using immobilized whole cells of Rhizopus oryzae in n-hexane system

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Devanesan; Rajendran, Aravindan; Thangavelu, Viruthagiri [Annamalai University, Department of Chemical Engineering, Faculty of Engineering and Technology, Biochemical Engineering Laboratory, Annamalai Nagar, Tamil Nadu (India)

    2012-03-15

    Non-edible oils represent one of the most viable alternative feed stocks for the production of large volumes of biodiesel at cheaper cost in tropical countries. The objective of the present study is to investigate the ability of the immobilized whole cells of Rhizopus oryzae MTCC 262 to catalyze the biodiesel production from karanja oil in n-hexane system. Response surface methodology was employed to evaluate the effects of synthesis parameters, such as molar ratio of oil to alcohol, reaction temperature and reaction time on percentage biodiesel (methyl esters) yield. Transesterification was performed in shake flasks containing immobilized cells in the reaction mixture with 10% oil weight of n-hexane. The quadratic effects of molar ratio of oil to alcohol and reaction time proved to be the significant at 1% and 5% levels, respectively. The optimum synthesis conditions were found to be: molar ratio of oil to alcohol 1:2.73, reaction temperature 41.39 C and reaction time 73.97 h. Biodiesel yield (methyl ester) was 75.98 (wt.%) under the optimal conditions and the subsequent verification experiments with biodiesel yield of 78.0 (wt.%) confirmed the validity of the proposed model. (orig.)

  8. Analysis of results of ASTP experiment in electrophoresis

    Science.gov (United States)

    Vanderhoff, J. W.; Micale, F. J.; Krumrine, P. H.

    1977-01-01

    The Apollo-Soyuz Test Project (ASTP) included an electrophoretic separation experiment of biological cells. The nature separation results of aldehyde-fixed rabbit, human and horse red blood cells, which were taken in the form of photographs taken at three-minute intervals, are the subject of this report. The electrophoretic separation was successful in that fractionation according to mobility did occur and was found in the sliced samples. Photographic evidence indicates that the low electroosmotic methylcellulose coating was successful in reducing the electroosmosis to a near zero value. Also, the flight film shows that the bands migrated down the column as theory would predict, producing two bands of high cell concentration separated and surrounded by regions of lower cell concentration. However, most likely some clumping of cells occurred to cause the trailing band to be larger than expected from theory. Overall, the experiment was a success in demonstrating a static electrophoresis separation under microgravity conditions with a resolution not possible on earth.

  9. Covalent immobilization of lysozyme onto woven and knitted crimped polyethylene terephthalate grafts to minimize the adhesion of broad spectrum pathogens

    International Nuclear Information System (INIS)

    Al Meslmani, Bassam M.; Mahmoud, Gihan F.; Leichtweiß, Thomas; Strehlow, Boris; Sommer, Frank O.; Lohoff, Michael D.; Bakowsky, Udo

    2016-01-01

    Graft-associated infections entirely determine the short-term patency of polyethylene terephthalate PET cardiovascular graft. We attempted to enzymatically inhibit the initial bacterial adhesion to PET grafts using lysozyme. Lysozyme was covalently immobilized onto woven and knitted forms of crimped PET grafts by the end-point method. Our figures of merit revealed lysozyme immobilization yield of 15.7 μg/cm"2, as determined by the Bradford assay. The activity of immobilized lysozyme on woven and knitted PET manifested 58.4% and 55.87% using Micrococcus lysodeikticus cells, respectively. Noteworthy, the adhesion of vein catheter-isolated Staphylococcus epidermidis decreased by 6- to 8-folds and of Staphylococcus aureus by 11- to 12-folds, while the Gram-negative Escherichia coli showed only a decrease by 3- to 4-folds. The anti-adhesion efficiency was specific for bacterial cells and no significant effect was observed on adhesion and growth of L929 cells. In conclusion, immobilization of lysozyme onto PET grafts can inhibit the graft-associated infection. - Highlights: • Lysozyme was covalently immobilized on crimped polyethylene terephthalate (PET). • The activity of immobilized lysozyme was meaningfully reduced. • The maintained activity significantly declined the adhesion of Gram-positive stains. • The enzymatic anti-adhesion efficiency reported lesser extent against Gram-negative. • The anti-bacterial activity displayed no significant effect on cells compatibility.

  10. Covalent immobilization of lysozyme onto woven and knitted crimped polyethylene terephthalate grafts to minimize the adhesion of broad spectrum pathogens

    Energy Technology Data Exchange (ETDEWEB)

    Al Meslmani, Bassam M., E-mail: almeslmanib@yahoo.com [Department of Pharmaceutical Technology and Biopharmaceutics, Marburg University, Ketzerbach 63, 35037 Marburg (Germany); Mahmoud, Gihan F., E-mail: mahmoudg@staff.uni-marburg.de [Department of Pharmaceutical Technology and Biopharmaceutics, Marburg University, Ketzerbach 63, 35037 Marburg (Germany); Department of Pharmaceutics and Industrial Pharmacy, Helwan University, Ain Helwan, 11795 Cairo (Egypt); Leichtweiß, Thomas, E-mail: Thomas.Leichtweiss@phys.Chemie.uni-giessen.de [Institute of Physical Chemistry, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 58, 35392 Giessen (Germany); Strehlow, Boris, E-mail: strehlo4@staff.uni-marburg.de [Department of Pharmaceutical Technology and Biopharmaceutics, Marburg University, Ketzerbach 63, 35037 Marburg (Germany); Sommer, Frank O., E-mail: sommerf@med.uni-marburg.de [Institute for Medical Microbiology and Hospital Hygiene, Marburg University, Hans Meerwein Str 2, 35032 Marburg (Germany); Lohoff, Michael D., E-mail: lohoff@med.uni-marburg.de [Institute for Medical Microbiology and Hospital Hygiene, Marburg University, Hans Meerwein Str 2, 35032 Marburg (Germany); Bakowsky, Udo, E-mail: ubakowsky@aol.com [Department of Pharmaceutical Technology and Biopharmaceutics, Marburg University, Ketzerbach 63, 35037 Marburg (Germany)

    2016-01-01

    Graft-associated infections entirely determine the short-term patency of polyethylene terephthalate PET cardiovascular graft. We attempted to enzymatically inhibit the initial bacterial adhesion to PET grafts using lysozyme. Lysozyme was covalently immobilized onto woven and knitted forms of crimped PET grafts by the end-point method. Our figures of merit revealed lysozyme immobilization yield of 15.7 μg/cm{sup 2}, as determined by the Bradford assay. The activity of immobilized lysozyme on woven and knitted PET manifested 58.4% and 55.87% using Micrococcus lysodeikticus cells, respectively. Noteworthy, the adhesion of vein catheter-isolated Staphylococcus epidermidis decreased by 6- to 8-folds and of Staphylococcus aureus by 11- to 12-folds, while the Gram-negative Escherichia coli showed only a decrease by 3- to 4-folds. The anti-adhesion efficiency was specific for bacterial cells and no significant effect was observed on adhesion and growth of L929 cells. In conclusion, immobilization of lysozyme onto PET grafts can inhibit the graft-associated infection. - Highlights: • Lysozyme was covalently immobilized on crimped polyethylene terephthalate (PET). • The activity of immobilized lysozyme was meaningfully reduced. • The maintained activity significantly declined the adhesion of Gram-positive stains. • The enzymatic anti-adhesion efficiency reported lesser extent against Gram-negative. • The anti-bacterial activity displayed no significant effect on cells compatibility.

  11. Identification of Receptor Ligands and Receptor Subtypes Using Antagonists in a Capillary Electrophoresis Single-Cell Biosensor Separation System

    Science.gov (United States)

    Fishman, Harvey A.; Orwar, Owe; Scheller, Richard H.; Zare, Richard N.

    1995-08-01

    A capillary electrophoresis system with single-cell biosensors as a detector has been used to separate and identify ligands in complex biological samples. The power of this procedure was significantly increased by introducing antagonists that inhibited the cellular response from selected ligand-receptor interactions. The single-cell biosensor was based on the ligand-receptor binding and G-protein-mediated signal transduction pathways in PC12 and NG108-15 cell lines. Receptor activation was measured as increases in cytosolic free calcium ion concentration by using fluorescence microscopy with the intracellular calcium ion indicator fluo-3 acetoxymethyl ester. Specifically, a mixture of bradykinin (BK) and acetylcholine (ACh) was fractionated and the components were identified by inhibiting the cellular response with icatibant (HOE 140), a selective antagonist to the BK B_2 receptor subtype (B_2BK), and atropine, an antagonist to muscarinic ACh receptor subtypes. Structurally related forms of BK were also identified based on inhibiting B_2BK receptors. Applications of this technique include identification of endogenous BK in a lysate of human hepatocellular carcinoma cells (Hep G2) and screening for bioactivity of BK degradation products in human blood plasma. The data demonstrate that the use of antagonists with a single-cell biosensor separation system aids identification of separated components and receptor subtypes.

  12. Membranes suited for immobilizing biomolecules

    NARCIS (Netherlands)

    2009-01-01

    The present invention relates to flow-through membranes suitable for the immobilization of biomols., methods for the prepn. of such membranes and the use of such membranes for the immobilization of biomols. and subsequent detection of immobilized biomols. The invention concerns a flow-through

  13. Characterization of bioactive RGD peptide immobilized onto poly(acrylic acid) thin films by plasma polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Hyun Suk; Ko, Yeong Mu; Shim, Jae Won [Department of Dental Materials, School of Dentistry, MRC Center, Chosun University, Gwangju (Korea, Republic of); Lim, Yun Kyong; Kook, Joong-Ki [Department of Oral Biochemistry, School of Dentistry, Chosun University, Gwangju (Korea, Republic of); Cho, Dong-Lyun [School of Applied Chemical Engineering and Center for Functional Nano Fine Chemicals, Chonnam National University, Gwangju (Korea, Republic of); Kim, Byung Hoon, E-mail: kim5055@chosun.ac.kr [Department of Dental Materials, School of Dentistry, MRC Center, Chosun University, Gwangju (Korea, Republic of)

    2010-11-01

    Plasma surface modification can be used to improve the surface properties of commercial pure Ti by creating functional groups to produce bioactive materials with different surface topography. In this study, a titanium surface was modified with acrylic acid (AA) using a plasma treatment and immobilized with bioactive arginine-glycine-aspartic acid (RGD) peptide, which may accelerate the tissue integration of bone implants. Both terminals containing the -NH{sub 2} of RGD peptide sequence and -COOH of poly(acrylic acid) (PAA) thin film were combined with a covalent bond in the presence of 1-ethyl-3-3-dimethylaminopropyl carbodiimide (EDC). The chemical structure and morphology of AA film and RGD immobilized surface were investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), atomic force microscopy (AFM), and scanning electron microscopy (SEM). All chemical analysis showed full coverage of the Ti substrate with the PAA thin film containing COOH groups and the RGD peptide. The MC3T3-E1 cells were cultured on each specimen, and the cell alkaline phosphatase (ALP) activity were examined. The surface-immobilized RGD peptide has a significantly increased the ALP activity of MC3T3-E1 cells. These results suggest that the RGD peptide immobilization on the titanium surface has an effect on osteoblastic differentiation of MC3T3-E1 cells and potential use in osteo-conductive bone implants.

  14. 21 CFR 862.2485 - Electrophoresis apparatus for clinical use.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Electrophoresis apparatus for clinical use. 862.2485 Section 862.2485 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Instruments § 862.2485 Electrophoresis apparatus for clinical use. (a) Identification. An electrophoresis...

  15. Effect of furfural on ethanol production by S. cerevisiae in a cross-linked immobilized cell reactor

    Energy Technology Data Exchange (ETDEWEB)

    Boyer, L.J.; Vega, J.L.; Basu, R.; Clausen, E.C.; Gaddy, J.L. (Arkansas Univ., Fayetteville, AR (United States). Dept. of Chemical Engineering)

    1992-01-01

    Furfural, a browning reaction product, inhibits yeast (Saccharomyces cerevisiae) growth and metabolism at low concentration levels in batch culture. The performance of an immobilized cell reactor (ICR) in the presence of 0-2.0 g l[sup -1] of furfural was examined. Cell growth in the ICR, with and without furfural in the media, indicated that either furfural did not impair glucose utilization, or that the negative effects of furfural were negated by increasing cell density in the reactor. Ethanol yields were constant at 0.48 g ethanol per g glucose regardless of the furfural concentration in the media. Although the specific productivity in the ICR decreased with furfural concentration, the productivity based on liquid hold-up remained constant. Furfural was depleted in the ICR during the experimental operation. Thus, furfural levels of 2.0 g 1[sup -1] or less can be tolerated by the yeast for ethanol production in the ICR without negatively affecting reactor performance. (author).

  16. Isotropically etched radial micropore for cell concentration, immobilization, and picodroplet generation.

    Science.gov (United States)

    Perroud, Thomas D; Meagher, Robert J; Kanouff, Michael P; Renzi, Ronald F; Wu, Meiye; Singh, Anup K; Patel, Kamlesh D

    2009-02-21

    To enable several on-chip cell handling operations in a fused-silica substrate, small shallow micropores are radially embedded in larger deeper microchannels using an adaptation of single-level isotropic wet etching. By varying the distance between features on the photolithographic mask (mask distance), we can precisely control the overlap between two etch fronts and create a zero-thickness semi-elliptical micropore (e.g. 20 microm wide, 6 microm deep). Geometrical models derived from a hemispherical etch front show that micropore width and depth can be expressed as a function of mask distance and etch depth. These models are experimentally validated at different etch depths (25.03 and 29.78 microm) and for different configurations (point-to-point and point-to-edge). Good reproducibility confirms the validity of this approach to fabricate micropores with a desired size. To illustrate the wide range of cell handling operations enabled by micropores, we present three on-chip functionalities: continuous-flow particle concentration, immobilization of single cells, and picoliter droplet generation. (1) Using pressure differentials, particles are concentrated by removing the carrier fluid successively through a series of 44 shunts terminated by 31 microm wide, 5 microm deep micropores. Theoretical values for the concentration factor determined by a flow circuit model in conjunction with finite volume modeling are experimentally validated. (2) Flowing macrophages are individually trapped in 20 microm wide, 6 microm deep micropores by hydrodynamic confinement. The translocation of transcription factor NF-kappaB into the nucleus upon lipopolysaccharide stimulation is imaged by fluorescence microscopy. (3) Picoliter-sized droplets are generated at a 20 microm wide, 7 microm deep micropore T-junction in an oil stream for the encapsulation of individual E. coli bacteria cells.

  17. Decolorization of industrial synthetic dyes using engineered Pseudomonas putida cells with surface-immobilized bacterial laccase

    Directory of Open Access Journals (Sweden)

    Wang Wei

    2012-06-01

    Full Text Available Abstract Background Microbial laccases are highly useful in textile effluent dye biodegradation. However, the bioavailability of cellularly expressed or purified laccases in continuous operations is usually limited by mass transfer impediment or enzyme regeneration difficulty. Therefore, this study develops a regenerable bacterial surface-displaying system for industrial synthetic dye decolorization, and evaluates its effects on independent and continuous operations. Results A bacterial laccase (WlacD was engineered onto the cell surface of the solvent-tolerant bacterium Pseudomonas putida to construct a whole-cell biocatalyst. Ice nucleation protein (InaQ anchor was employed, and the ability of 1 to 3 tandemly aligned N-terminal repeats to direct WlacD display were compared. Immobilized WlacD was determined to be surface-displayed in functional form using Western blot analysis, immunofluorescence microscopy, flow cytometry, and whole-cell enzymatic activity assay. Engineered P. putida cells were then applied to decolorize the anthraquinone dye Acid Green (AG 25 and diazo-dye Acid Red (AR 18. The results showed that decolorization of both dyes is Cu2+- and mediator-independent, with an optimum temperature of 35°C and pH of 3.0, and can be stably performed across a temperature range of 15°C to 45°C. A high activity toward AG25 (1 g/l with relative decolorization values of 91.2% (3 h and 97.1% (18 h, as well as high activity to AR18 (1 g/l by 80.5% (3 h and 89.0% (18 h, was recorded. The engineered system exhibited a comparably high activity compared with those of separate dyes in a continuous three-round shake-flask decolorization of AG25/AR18 mixed dye (each 1 g/l. No significant decline in decolorization efficacy was noted during first two-rounds but reaction equilibriums were elongated, and the residual laccase activity eventually decreased to low levels. However, the decolorizing capacity of the system was easily retrieved

  18. Acetate production from whey lactose using co-immobilized cells of homolactic and homoacetic bacteria in a fibrous-bed bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Y.; Yang, S.T. [Ohio State Univ., Columbus, OH (United States). Dept. of Chemical Engineering

    1998-11-20

    Acetate was produced from whey lactose in batch and fed-batch fermentations using co-immobilized cells of Clostridium formicoaceticum and Lactococcus lactis. The cells were immobilized in a spirally wound fibrous sheet packed in a 0.45-L column reactor, with liquid circulated through a 5-L stirred-tank fermentor. Industrial-grade nitrogen sources, including corn steep liquor, casein hydrolysate, and yeast hydrolysate, were studied as inexpensive nutrient supplements to whey permeate and acid whey. Supplementation with either 2.5% (v/v) corn steep liquor or 1.5 g/L casein hydrolysate was adequate for the cocultured fermentation. The overall acetic acid yield from lactose was 0.9 g/g, and the productivity was 0.25 g/(L h). Both lactate and acetate at high concentrations inhibited the homoacetic fermentation. To overcome these inhibitions, fed-batch fermentations were used to keep lactate concentration low and to adapt cells to high-concentration acetate. The final acetate concentration obtained in the fed-batch fermentations were used to keep lactate concentration low and to adapt cells to high-concentration acetate. The final acetate concentration obtained in the fed-batch fermentation was 75 g/L, which was the highest acetate concentration ever produced by C. formicoaceticum. Even at this high acetate concentration, the overall productivity was 0.18 g/(L h) based on the total medium volume and 1.23 g/(L h) based on the fibrous-bed reactor volume. The cells isolated from the fibrous-bed bioreactor at the end of this study were more tolerant to acetic acid than the original culture used to seed the bioreactor, indicating that adaptation and natural selection of acetate-tolerant strains occurred. This cocultured fermentation process could be used to produce a low-cost acetate deicer from whey permeate and acid whey.

  19. Alcoholic fermentation by immobilized yeast at high sugar concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Holcberg, I.B.; Margalith, P.

    1981-01-01

    Glucose fermentation by Saccharomyces cerevisiae immobilized by entrapment in agar, carrageenan, alginate and polyacrylamide gels, was compared to that of freely suspended cells at concentration of 10-50% (w.w.) sugar. The rate of ethanol production by the entrapped cells was 20-25% higher than that of the free cells. Concentrations of up to 14.5% w/w ethanol (30% glucose initial concentration) could be obtained. A number of hypotheses for the improved alcoholic fermentation are discussed.

  20. Immobilization of fish chromatophores for use as a micro-biosensor for biological toxins

    Directory of Open Access Journals (Sweden)

    Mojović Ljiljana V.

    2003-01-01

    Full Text Available Chromatophores isolated from the Siamese fighting fish, Betta splendens represent a class of living cells that provide a vivid color response to microbial pathogens and environmental toxins. The selection of the most appropriate microcarrier and the development of the optimal technique for the chromatophore immobilization in order to enable directed transport of the sensor cells throughout microchannels of the biosensor, as well to preserve the cell survival and its functionality was studied. Microcarriers derived from glass, polystyrene and gelatin (collagen were tested as substrates for chromatophore attachement. Gelatin microcarriers were found to be the most suitable, due to high attachment efficiency (95% of attached cells, preservation of the cell viability and enhanced cell sensitivity. The optimum conditions for fish cell immobilization on collagen microcarriers were determined based on the cell-to-microcarrier bead ratio and the pH of the solution. The rate of cell attachment to the gelatin microcarrier followed first-order kinetics. Pretreatment of the gelatin beads with fibronectin, known as a cell attachment-promoting agent, resulted in a 10% higher attachment rate constant (k.

  1. Electrophoresis microchip with integrated waveguides for simultaneous native UV fluorescence and absorbance detection

    DEFF Research Database (Denmark)

    Ohlsson, Pelle Daniel; Sala, Olga Ordeig; Mogensen, Klaus Bo

    2009-01-01

    Simultaneous label-free detection of UV absorbance and native UV-excited fluorescence in an electrophoresis microchip is presented. UV transparent integrated waveguides launch light at a wavelength of 254 nm from a mercury lamp along the length of a 1-mm. long detection cell. Transmitted UV light...

  2. 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.

  3. The fluid mechanics of continuous flow electrophoresis

    Science.gov (United States)

    Saville, D. A.

    1990-01-01

    The overall objective is to establish theoretically and confirm experimentally the ultimate capabilities of continuous flow electrophoresis chambers operating in an environment essentially free of particle sedimentation and buoyancy. The efforts are devoted to: (1) studying the effects of particle concentration on sample conductivity and dielectric constant. The dielectric constant and conductivity were identified as playing crucial roles in the behavior of the sample and on the resolving power and throughput of continuous flow devices; and (2) improving the extant mathematical models to predict flow fields and particle trajectories in continuous flow electrophoresis. A dielectric spectrometer was designed and built to measure the complex dielectric constant of a colloidal dispersion as a function of frequency between 500 Hz and 200 kHz. The real part of the signal can be related to the sample's conductivity and the imaginary part to its dielectric constant. Measurements of the dielectric constants of several different dispersions disclosed that the dielectric constants of dilute systems of the sort encountered in particle electrophoresis are much larger than would be expected based on the extant theory. Experiments were carried out to show that, in many cases, this behavior is due to the presence of a filamentary structure of small hairs on the particle surface. A technique for producing electrokinetically ideal synthetic latex particles by heat treating was developed. Given the ubiquitous nature of hairy surfaces with both cells and synthetic particles, it was deemed necessary to develop a theory to explain their behavior. A theory for electrophoretic mobility of hairy particles was developed. Finally, the extant computer programs for predicting the structure of electro-osmotically driven flows were extended to encompass flow channels with variable wall mobilities.

  4. SYNTHESIS, CHARACTERIZATION AND APPLICATION OF A POLYURETHANE-BASED SUPPORT FOR IMMOBILIZING MEMBRANE-BOUND LIPASE

    Directory of Open Access Journals (Sweden)

    M. S. Soares

    Full Text Available Abstract This study conducted an assessment of polyurethane foams that were synthesized by one-shot process and used as a low-cost support to immobilize Mucor circinelloides URM 4182 whole-cells presenting high lipolytic activity. Polyols with different molecular weights (1100 to 6000 g mol-1 were applied to synthesize the polymer matrix, and the agitation speed effect was used for controlling the average pore size of the investigated polyurethane foams. The physical and mechanical properties of the polymers were evaluated by standard test methods, and their morphology was identified by Scanning Electron Microscopy. The immobilization procedure efficiency was assessed by quantifying the capability of the matrices to attach the cells and the catalytic activity of the biocatalysts in both aqueous (olive oil hydrolysis and non-aqueous media (ethanolysis of babassu oil under single and consecutive batch runs. Although all synthesized matrices were suitable to immobilize the whole cells with high catalytic performance, a better set of parameters was attained when the polyol ether with molecular weight of 6000 g mol-1 and 1100 g mol-1 was used. Both matrices yielded immobilized biocatalysts with high hydrolysis and transesterification activities, and exhibited a satisfactory operational stability with 96% and 81% retention of their initial hydrolytic and transesterification activities after three consecutive batch runs.

  5. The effects of the fermentation with immobilized yeast and different cherry varieties on the quality of cherry brandy

    Directory of Open Access Journals (Sweden)

    R. Miličević

    2014-01-01

    Full Text Available The aim of this research was to investigate influence of different fermentation processes (by immobilized yeast cells and classical fermentation and different cherry varieties (Maraska, Montmorencys and Kelleris on the chemical and sensorial characteristics of cherry brandies. Cherry brandies were analyzed to determine chemical composition, aroma profile and sensory properties. Cherry brandies produced by immobilized yeast cells had a higher content of aldehydes, but lower content of total acids, total extract, higher alcohols and esters compared to the samples produced by classical fermentation process. Furfural was not detected in cherry distillates produced by immobilized yeast cells, while distillates produced by classical fermentation process had very low content. Cherry brandies produced by classical fermentation process had significantly higher content of benzaldehyde which has great influence on aroma of cherry brandies. Ethyl octanoate which is considered one of the most important contributors to the aroma of alcoholic distillates was found in the highest concentrations in Maraska distillates. The best evaluated sample was brandy produced from Maraska cherry variety fermented by immobilized yeast cells followed by brandy produced also from Maraska cherry variety, but by classical fermentation process.

  6. Effects of joint immobilization on changes in myofibroblasts and collagen in the rat knee contracture model.

    Science.gov (United States)

    Sasabe, Ryo; Sakamoto, Junya; Goto, Kyo; Honda, Yuichiro; Kataoka, Hideki; Nakano, Jiro; Origuchi, Tomoki; Endo, Daisuke; Koji, Takehiko; Okita, Minoru

    2017-09-01

    The purpose of this study was to examine the time-dependent changes in the development of joint capsule fibrosis and in the number of myofibroblasts in the joint capsule after immobilization, using a rat knee contracture model. Both knee joints were fixed in full flexion for 1, 2, and 4 weeks (immobilization group). Untreated rats were bred for each immobilization period (control group). Histological analysis was performed to evaluate changes in the amount and density of collagen in the joint capsule. The changes in type I and III collagen mRNA were examined by in situ hybridization. The number of myofibroblasts in the joint capsule was assessed by immunohistochemical methods. In the immobilization group, the amount of collagen increased within 1 week and the density of collagen increased within 2 weeks, as compared with that in the control group. Type I collagen mRNA-positive cell numbers in the immobilization group increased at all time points. However, type III collagen mRNA-positive cell numbers did not increase. Myofibroblasts in the immobilization group significantly increased compared with those in the control group at all time points, and they increased significantly with the period of immobilization. These results suggest that joint capsule fibrosis with overexpression of type I collagen occurs and progresses within 1 week after immobilization, and an increase in myofibroblasts is related to the mechanism of joint capsule fibrosis. The findings suggest the need for a treatment targeting accumulation of type I collagen associated with an increase in myofibroblasts. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1998-2006, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  7. Characteristics of immobilized lactobacillus delbrueckii in a liquid-solid fluidized bed bioreactor for lactic acid production

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Henian; Seki, M.; Furusaki, S. [The Univ. of Tokyo (Japan). Faculty of Engineering

    1995-04-20

    A fluidized bed bioreactor was employed for lactic acid production using immobilized cells. First, the cell release rate was discussed. A liquid-solid fluidized bed reactor with immobilized cells was used to perform continuous lactic acid fermentation without any operational problems. The performance of the reactor was investigated under different conditions. Cell release rate and contribution of free cells to lactic acid production were studied quantitatively. The results showed that under low gel holdup and low dilution rate conditions, free cells played a significant role in lactic acid production. However, increasing solid holdup decreased the free cell concentration in the broth due to high lactic acid concentration and also decreased the contribution of the free cells to lactic acid production. The effects of growth nutrients on reactor performance were investigated. 16 refs., 12 figs.

  8. Capillary zone electrophoresis-tandem mass spectrometry detects low concentration host cell impurities in monoclonal antibodies

    Science.gov (United States)

    Zhu, Guijie; Sun, Liangliang; Heidbrink-Thompson, Jennifer; Kuntumalla, Srilatha; Lin, Hung-yu; Larkin, Christopher J.; McGivney, James B.; Dovichi, Norman J.

    2016-01-01

    We have evaluated capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry (CZE-ESI-MS/MS) for detection of trace amounts of host cell protein impurities in recombinant therapeutics. Compared to previously published procedures, we have optimized the buffer pH used in the formation of a pH junction to increase injection volume. We also prepared a five-point calibration curve by spiking twelve standard proteins into a solution of a human monoclonal antibody. A custom CZE-MS/MS system was used to analyze the tryptic digest of this mixture without depletion of the antibody. CZE generated a ~70 min separation window (~90 min total analysis duration) and ~300 peak capacity. We also analyzed the sample using ultra-performance liquid chromatography (UPLC)-MS/MS. CZE-MS/MS generated ~five times higher base peak intensity and more peptide identifications for low-level spiked proteins. Both methods detected all proteins spiked at the ~100 ppm level with respect to the antibody. PMID:26530276

  9. Cytoskeletal proteins from human skin fibroblasts, peripheral blood leukocytes, and a lymphoblastoid cell line compared by two-dimensional gel electrophoresis

    International Nuclear Information System (INIS)

    Giometti, C.S.; Willard, K.E.; Anderson, N.L.

    1982-01-01

    Differences in proteins between cells grown as suspension cultures and those grown as attached cultures were studied by comparing the proteins of detergent-resistant cytoskeletons prepared from peripheral blood leukocytes and a lymphoblastoid cell line (GM607) (both grown as suspension cultures) and those of human skin fibroblasts (grown as attached cultures) by two-dimensional gel electrophoresis. The major cytoskeletal proteins of the leukocytes were also present in the protein pattern of GM607 cytoskeletons. In contrast, the fibroblast cytoskeletal protein pattern contained four groups of proteins that differed from the patterns of the leukocytes and GM607. In addition, surface labeling of GM607 and human fibroblasts with 125 I demonstrated that substantial amounts of vimentin and actin are exposed at the surface of the attached fibroblasts, but there is little evidence of similar exposure at the surface of the suspension-grown GM607. These results demonstrate some differences in cytoskeletal protein composition between different types of cells could be related to their ability or lack of ability to grow as attached cells in tissue culture

  10. Polysialic acid immobilized on silanized glass surfaces: a test case for its use as a biomaterial for nerve regeneration.

    Science.gov (United States)

    Steinhaus, Stephanie; Stark, Yvonne; Bruns, Stephanie; Haile, Yohannes; Scheper, Thomas; Grothe, Claudia; Behrens, Peter

    2010-04-01

    The immobilization of polysialic acid (polySia) on glass substrates has been investigated with regard to the applicability of this polysaccharide as a novel, biocompatible and bioresorbable material for tissue engineering, especially with regard to its use in nerve regeneration. PolySia, a homopolymer of alpha-2,8-linked sialic acid, is involved in post-translational modification of the neural cell adhesion molecule (NCAM). The degradation of polySia can be controlled which makes it an interesting material for coating and for scaffold construction in tissue engineering. Here, we describe the immobilization of polySia on glass surfaces via an epoxysilane linker. Whereas glass surfaces will not actually be used in nerve regeneration scaffolds, they provide a simple and efficient means for testing various methods for the investigation of immobilized polySia. The modified surfaces were investigated with contact angle measurements and the quantity of immobilized polySia was examined by the thiobarbituric acid assay and a specific polySia-ELISA. The interactions between the polySia-modified surface and immortalized Schwann cells were evaluated via cell adhesion and cell viability assays. The results show that polySia can be immobilized on glass surfaces via the epoxysilane linker and that surface-bound polySia has no toxic effects on Schwann cells. Therefore, as a key substance in the development of vertebrates and as a favourable substrate for the cultivation of Schwann cells, it offers interesting features for the use in nerve guidance tubes for treatment of peripheral nerve injuries.

  11. Practical capillary electrophoresis

    CERN Document Server

    Weinberger, Robert

    2000-01-01

    In the 1980s, capillary electrophoresis (CE) joined high-performance liquid chromatography (HPLC) as the most powerful separation technique available to analytical chemists and biochemists. Published research using CE grew from 48 papers in the year of commercial introduction (1988) to 1200 in 1997. While only a dozen major pharmaceutical and biotech companies have reduced CE to routine practice, the applications market is showing real or potential growth in key areas, particularly in the DNA marketplace for genomic mapping and forensic identification. For drug development involving small molecules (including chiral separations), one CE instrument can replace 10 liquid chromatographs in terms of speed of analysis. CE also uses aqueous rather than organic solvents and is thus environmentally friendlier than HPLC. The second edition of Practical Capillary Electrophoresis has been extensively reorganized and rewritten to reflect modern usage in the field, with an emphasis on commercially available apparatus and ...

  12. An overview of technologies for immobilization of enzymes and surface analysis techniques for immobilized enzymes

    Science.gov (United States)

    Mohamad, Nur Royhaila; Marzuki, Nur Haziqah Che; Buang, Nor Aziah; Huyop, Fahrul; Wahab, Roswanira Abdul

    2015-01-01

    The current demands of sustainable green methodologies have increased the use of enzymatic technology in industrial processes. Employment of enzyme as biocatalysts offers the benefits of mild reaction conditions, biodegradability and catalytic efficiency. The harsh conditions of industrial processes, however, increase propensity of enzyme destabilization, shortening their industrial lifespan. Consequently, the technology of enzyme immobilization provides an effective means to circumvent these concerns by enhancing enzyme catalytic properties and also simplify downstream processing and improve operational stability. There are several techniques used to immobilize the enzymes onto supports which range from reversible physical adsorption and ionic linkages, to the irreversible stable covalent bonds. Such techniques produce immobilized enzymes of varying stability due to changes in the surface microenvironment and degree of multipoint attachment. Hence, it is mandatory to obtain information about the structure of the enzyme protein following interaction with the support surface as well as interactions of the enzymes with other proteins. Characterization technologies at the nanoscale level to study enzymes immobilized on surfaces are crucial to obtain valuable qualitative and quantitative information, including morphological visualization of the immobilized enzymes. These technologies are pertinent to assess efficacy of an immobilization technique and development of future enzyme immobilization strategies. PMID:26019635

  13. Cyclin-dependent kinase inhibitor, roscovitine, in combination with exogenous cytokinin, N6-benzyladenine, causes increase of cis-cytokinins in immobilized tobacco cells

    Czech Academy of Sciences Publication Activity Database

    Blagoeva, Elitsa; Malbeck, Jiří; Gaudinová, Alena; Vaněk, Tomáš; Vaňková, Radomíra

    2003-01-01

    Roč. 25, č. 6 (2003), s. 469-472 ISSN 0141-5492 R&D Projects: GA MŠk OC 840.20; GA MŠk LN00A081 Institutional research plan: CEZ:AV0Z4055905; CEZ:AV0Z5038910 Keywords : alginate * cytokinins * plant cell immobilization Subject RIV: ED - Physiology Impact factor: 0.778, year: 2003

  14. Misleading presentation of haemoglobin electrophoresis data | Adu ...

    African Journals Online (AJOL)

    Haemoglobinopathies are common in sub-Saharan Africa. As such haemoglobin electrophoresis are required to inform clinical decision making. However, haemoglobin electrophoresis is an assay that detects protein at either alkaline or acidic pH. Such assays do not interrogate gene sequences but rather the product of a ...

  15. Comparison of lipoprotein electrophoresis and apolipoprotein e genotyping in investigating dysbetalipoproteinemia

    International Nuclear Information System (INIS)

    Ahmed, F.; Kadiki, A.E.

    2017-01-01

    Dysbetalipoproteinemia is often associated with apolipoprotein E2E2 homozygosity; however, lipoprotein electrophoresis may also be used to assist in the diagnosis. The aim of this study was to compare apolipoprotein E (apo E) genotyping and lipoprotein electrophoresis in investigating dysbetalipoproteinemia. Data were collected over a three-year period from a lipid clinic in a tertiary referral centre and reviewed for apo E genotyping and lipoprotein electrophoresis. Sixty-two patients had both apo E genotyping and lipoprotein electrophoresis. Of these, 16 patients showed broad beta band on electrophoresis. However, only 3 of them had apo E2E2 homozygosity on genotyping. Lipoprotein electrophoresis and apo E genotyping results showed poor concordance. This was primarily due to visual interpretation error of lipoprotein electrophoresis which may over diagnose dysbetalipoproteinemia. (author)

  16. Comparison of Lipoprotein Electrophoresis and Apolipoprotein E Genotyping in Investigating Dysbetalipoproteinemia.

    Science.gov (United States)

    Ahmed, Farhan; El-Kadiki, Alia; Gibbons, Stephen

    2017-06-01

    Dysbetalipoproteinemia is often associated with apolipoprotein E2E2 homozygosity; however, lipoprotein electrophoresis may also be used to assist in the diagnosis. The aim of this study was to compare apolipoprotein E (apo E) genotyping and lipoprotein electrophoresis in investigating dysbetalipoproteinemia. Data were collected over a three-year period from a lipid clinic in a tertiary referral centre and reviewed for apo E genotyping and lipoprotein electrophoresis. Sixty-two patients had both apo E genotyping and lipoprotein electrophoresis. Of these, 16 patients showed broad beta band on electrophoresis. However, only 3 of them had apo E2E2 homozygosity on genotyping. Lipoprotein electrophoresis and apo E genotyping results showed poor concordance. This was primarily due to visual interpretation error of lipoprotein electrophoresis which may over diagnose dysbetalipoproteinemia.

  17. Conducting Polymer Electrodes for Gel Electrophoresis

    OpenAIRE

    Bengtsson, Katarina; Nilsson, Sara; Robinson, Nathaniel D

    2014-01-01

    In nearly all cases, electrophoresis in gels is driven via the electrolysis of water at the electrodes, where the process consumes water and produces electrochemical by-products. We have previously demonstrated that p-conjugated polymers such as poly(3,4-ethylenedioxythiophene) (PEDOT) can be placed between traditional metal electrodes and an electrolyte to mitigate electrolysis in liquid (capillary electroosmosis/electrophoresis) systems. In this report, we extend our previous result to gel ...

  18. Two-dimensional gel electrophoresis data for proteomic profiling of Sporothrix yeast cells

    Directory of Open Access Journals (Sweden)

    Anderson Messias Rodrigues

    2015-03-01

    Full Text Available Sporotrichosis is a chronic infection of the skin and subcutaneous tissues of human and other mammals caused by a complex of cryptic dimorphic fungi in the plant-associated order Ophiostomatales. With major differences between routes of transmission, Sporothrix infections are emerging as new threat in tropical and subtropical areas, particularly in form of outbreaks. The mechanisms underlying the pathogenesis and invasion of Sporothrix spp. are still poorly understood and many virulence factors remain unidentified. In this scenario, a global analysis of proteins expressed by clinical Sporothrix species combined with the identification of seroreactive proteins is overdue. Optimization of sample preparation and electrophoresis conditions are key steps toward reproducibility of gel-based proteomics assays. We provide the data generated using an efficient protocol of protein extraction for rapid and large-scale proteome analysis using two-dimensional gel electrophoresis. The protocol was established and optimized for pathogenic and non-pathogenic Sporothrix spp. including Sporothrix brasiliensis (CBS 132990, Sporothrix schenckii sensu stricto (CBS 132974, Sporothrix globosa (CBS 132922, and Sporothrix mexicana (CBS 120341. The data, supplied in this article, are related to the research article entitled “Immunoproteomic analysis reveals a convergent humoral response signature in the Sporothrix schenckii complex” (Rodrigues et al., 2014 [1].

  19. Feasibility of measuring radiation-induced DNA double strand breaks and their repair by pulsed field gel electrophoresis in freshly isolated cells from the mouse RIF-1 tumor

    International Nuclear Information System (INIS)

    Waarde, Maria A.W.H. van; Assen, Annette J. van; Konings, Antonius W.T.; Kampinga, Harm H.

    1996-01-01

    Purpose: To examine the technical feasibility of pulsed field gel electrophoresis (PFGE) as a predictive assay for the radio responsiveness of tumors. Induction and repair of DNA double strand breaks (DSBs) in a freshly prepared cell suspension from a RIF-1 tumor (irradiated ex vivo) was compared with DSB induction and repair in exponentially growing RIF-1 cells in culture (irradiated in vitro). Methods and Materials: A murine RIF-1 tumor grown in vivo was digested, and cells were exposed to x-rays (ex vivo) at doses of 1 to 75 Gy. DNA damage was measured using CHEF (clamped homogeneous electric fields) electrophoresis. Repair kinetics were studied at 37 deg. C for 4 h after irradiation. Radiosensitivity was determined by clonogenic assay, and cell cycle distributions by flow cytometry. For comparison, a trypsinized suspension of exponentially growing RIF-1 cells in vitro was run parallel with each ex vivo experiment. Results: Induction of DSBs, expressed as % DNA extracted from the plug, was similar in the in vitro and ex vivo irradiated cells. Compared to repair rates in in vitro cultured RIF-1 cells, repair kinetics in a freshly prepared cell suspension from the tumor were decreased, unrelated to differences in radiosensitivity. Differences in repair could not be explained by endogenous DNA degradation, nor by influences of enzymes used for digestion of the tumor. A lower plating efficiency and differences in ploidy (as revealed by flow cytometry) were the only reproducible differences between in vivo and in vitro grown cells that may explain the differences in repair kinetics. Conclusions: The current results do not support the idea that PFGE is a technique robust enough to be a predictive assay for the radiosensitivity of tumor cells

  20. Evaluation of radio-induced DNA damage and their repair in human lymphocytes by comet assay or single cell gel electrophoresis; Avaliacao do dano radioinduzido no DNA e reparo em linfocitos humanos pelo metodo do cometa (single cell gel electrophoresis)

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Patricia A. do; Suzuki, Miriam F.; Okazaki, Kayo [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    1997-12-01

    The comet assay, also called single cell gel electrophoresis technique, permits to evaluate quantitatively DNA breakage induced by chemical and physical agents at the level of the single cell. The present paper refers to the construction of dose-response curves to DNA damage and repair studies in human peripheral lymphocytes, utilizing the comet assay for the radiosensitivity analysis. So, the blood samples were obtained from healthy donors (40-50 year old), irradiated in a {sup 60} Co source (GAMMACEL 220) with doses of 0.17, 0.25, 0.57, 1.10, 2.12 and 4.22 Gy (0.59 Gy/min.) and processed 1 and 24 hours after the exposition. Results obtained showed a increase in the total lenght of comet (DNA migration) as a function of radiation dose in samples processed 1 and 24 hours after the treatment. The DNA lesion in irradiated lymphocytes with 4.22 Gy (means value of 101.4 {mu}m) were 3.4 times higher than in the untreated lymphocytes (mean value of 30 {mu}m) instead of 24 hours after the irradiation were 1.5 times higher (mean value of 46.3 {mu}m). This reduction on DNA repair occurred in these cells. It was also possible visualized the presence of subpopulations of the cells with different sensitivity and repair capacity to ionizing radiation in these donors. (author). 8 refs., 3 figs.

  1. Novel pectin-silica hybrids used for immobilization of Trichosporon cutaneum cells efficient in removal of Cadmium and Copper ions from waste water

    International Nuclear Information System (INIS)

    Georgieva, N.; Rangelova, N.; Peshev, D.; Nenkova, S.

    2011-01-01

    New silica hybrid materials containing tetramethyl siloxane (TMOS) as an inorganic precursor and apple pectin (AP) as an organic compound were prepared. The quantity of organic substance was 5 and 50 wt% AP. The amorphous state of the samples was proved by X-ray diffraction analyses (XRD). The Infrared scattering spectra (IR) showed characteristic peaks for SiO2 network, as well as for pectin. The synthesized hybrid materials were applied as matrices for cells immobilization by attachment and entrapment of the filamentous yeast Trichosporon cutaneum R57. This strain showed considerable ability to remove cadmium and copper ions from aqueous solutions. Regarding heavy metal biosorption capacity, the attachment was found to be superior compared to the entrapment method as a technique for biomass immobilization. (authors) Key words: biomaterials, composite materials, microstructure, sol-gel preparation

  2. DNA Sequencing by Capillary Electrophoresis

    Science.gov (United States)

    Karger, Barry L.; Guttman, Andras

    2009-01-01

    Sequencing of human and other genomes has been at the center of interest in the biomedical field over the past several decades and is now leading toward an era of personalized medicine. During this time, DNA sequencing methods have evolved from the labor intensive slab gel electrophoresis, through automated multicapillary electrophoresis systems using fluorophore labeling with multispectral imaging, to the “next generation” technologies of cyclic array, hybridization based, nanopore and single molecule sequencing. Deciphering the genetic blueprint and follow-up confirmatory sequencing of Homo sapiens and other genomes was only possible by the advent of modern sequencing technologies that was a result of step by step advances with a contribution of academics, medical personnel and instrument companies. While next generation sequencing is moving ahead at break-neck speed, the multicapillary electrophoretic systems played an essential role in the sequencing of the Human Genome, the foundation of the field of genomics. In this prospective, we wish to overview the role of capillary electrophoresis in DNA sequencing based in part of several of our articles in this journal. PMID:19517496

  3. Sodium alginate-grafted β-cyclodextrins as a matrix for immobilized Arthrobacter simplex for cortisone acetate biotransfromation

    Science.gov (United States)

    Shen, Yanbing; Niu, Lulu; Yu, Ziqi; Wang, Min; Shang, Zhihua; Yang, Yan

    2018-06-01

    Cyclodextrins (CDs) are used to resolve the low aqueous solubility of steroids, but the high cost of CDs is still a limiting factor in biotransformation process. This study, which is based on grafting and immobilization techniques, focused on synthesizing for the first time sodium alginate (SA)-grafted β-CD (SA-β-CD) and alginate-grafted β-CD for the immobilization of Arthrobacter simplex (ASP) cells (SA-β-CD-cells) and subsequent recycling of CDs and cells. FTIR spectium and X-ray diffraction proved that β-CD was successfully grafted with SA, whereas the grafting yield of β-CD was 10.3 μmol g-1. SA-β-CD could increase the solubility of CA by 3.5-fold, whereas the transformation rate was enhanced by 10%. The conversion ratio of CA was over 92% after the SA-β-CD recycling for nine cycles. In addition, after SA-β-CD-cells were applied in biocatalytic reactions for eight cycles, the conversion ratio of CA was over 90%. These advantages suggest great potential for using both grafting and immobilized techniques in steroid transformation.

  4. Immobilization of yeast inulinase on chitosan beads for the hydrolysis of inulin in a batch system.

    Science.gov (United States)

    Singh, R S; Singh, R P; Kennedy, J F

    2017-02-01

    An extracellular inulinase was partially purified by ethanol precipitation and gel exclusion chromatography from a cell free extract of Kluyveromyces marxianus. Partially purified inulinase exhibited 420 IU/mg specific activity and it was immobilized on chitosan beads. Activity yield of immobilized inulinase was optimized with glutaraldehyde concentration (1-5%), glutaraldehyde treatment time (30-240min), enzyme coupling-time (2-16h) and enzyme loading (5-30 IU) as functions. Under the optimized conditions maximum yield 65.5% of immobilized inulinase was obtained. Maximum hydrolysis of inulin 84.5% and 78.2% was observed at 125rpm after 4h by immobilized and free enzyme, respectively. A retention-time of 4h and 5h was found optimal for the hydrolysis of inulin under agitation (125rpm) by free and immobilized enzyme, respectively. The recycling of the developed immobilized biocatalyst was carried out after 5h of inulin hydrolysis in a batch system. The developed immobilized biocatalyst was successfully used for the hydrolysis of inulin for 14 batches. This is the first report on the immobilization of yeast inulinase on chitosan beads for the hydrolysis of inulin in a batch system. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Supramolecular protein immobilization on lipid bilayers

    NARCIS (Netherlands)

    Bosmans, R.P.G.; Hendriksen, W.E.; Verheijden, Mark Lloyd; Eelkema, R.; Jonkheijm, Pascal; van Esch, J.H.; Brunsveld, Luc

    2015-01-01

    Protein immobilization on surfaces, and on lipid bilayers specifically, has great potential in biomolecular and biotechnological research. Of current special interest is the immobilization of proteins using supramolecular noncovalent interactions. This allows for a reversible immobilization and

  6. Immobilized yeast in bioreactor for alcohol fermentation

    International Nuclear Information System (INIS)

    Handy, M.K.; Kim, K.

    1986-01-01

    Mutant of Saccharomyces cerevisiae was developed using a Co-60 source. Cells were immobilized onto sterile, channeled alumina beads and packed into bioreactor column under controlled temperature. Feedstocks containing substrate and nutrients were fed into the bioreactor at specific rates. Beads with greatest porosity and surface area produced the most ethanol. Factors affecting ethanol productivity included: temperature, pH, flow rate, nutrients and substrate in the feedstock

  7. Sol-gel immobilization as a suitable technique for enhancement of α-amylase activity of Aspergillus oryzae PP.

    Science.gov (United States)

    Evstatieva, Yana; Yordanova, Mariya; Chernev, Georgi; Ruseva, Yanislava; Nikolova, Dilyana

    2014-07-04

    Bioencapsulation of microbial cells in silica-based matrices has proved to be a good strategy to enhance the biosynthetic capabilities and viability of bioproducers. In the present study, mycelium and pellet cultures of strain Aspergillus oryzae PP were successfully immobilized in sol-gel hybrid matrices composed of tetraethylorthosilicate as an inorganic precursor, 5% (w/v) starch and 10 or 15% (w/v) polyethylene oxide, or 10% (w/v) calcium alginate as organic compounds. Biosynthetic activity of immobilized cultures was investigated by batch and fed-batch cultivation and the obtained results of 3042.04 IU cm -3 were comparable with the enzyme activity of the free cell culture. Immobilized cultures retained their viability and biosynthetic capabilities up to the 744th h during fed-batch fermentation processes. Consequently, sol-gel encapsulation in hybrid matrices could be considered as a promising technique for immobilization of Aspergillus oryzae PP in order to increase the α-amylase production.

  8. Urine protein electrophoresis test

    Science.gov (United States)

    Urine protein electrophoresis; UPEP; Multiple myeloma - UPEP; Waldenström macroglobulinemia - UPEP; Amyloidosis - UPEP ... special paper and apply an electric current. The proteins move and form visible bands. These reveal the ...

  9. A novel ethanol/oxygen microfluidic fuel cell with enzymes immobilized onto cantilevered porous electrodes

    Science.gov (United States)

    Desmaële, D.; Nguyen-Boisse, T. T.; Renaud, L.; Tingry, S.

    2016-11-01

    This paper introduces a novel design of membraneless microfluidic biofuel cell that incorporates three-dimensional porous electrodes containing immobilized enzymes to catalyze redox reactions occurring in the presence of ethanol/O2 co-laminar flows. In order to maximize the penetration depth of the reactants inside the porous medium, we report on the preliminary evaluation of cantilevered bioelectrodes, namely the fibrous electrodes protrude along the internal walls of the miniature electrochemical chamber. As a first proof-of-concept, we demonstrate the integration of a bioanode and a biocathode into a lamination-based microfluidic cell fabricated via rapid prototyping. With enzymes deposited into the fibrous structure of 25 mm long, 1 mm wide and 0.11 mm thick carbon paper electrodes, the volumetric power density reached 1.25 mW cm-3 at 0.43 V under a flow rate of 50 μL min-1. An advantage of the presented microfluidic biofuel cell is that it can be adapted to include a larger active electrode volume via the vertical stacking of multiple thin bioelectrodes. We therefore envision that our design would be amenable to reach the level of net power required to supply energy to a plurality of low-consumption electronic devices.

  10. Penanganan limbah industri dengan cara immobilisasi microbial cell

    Directory of Open Access Journals (Sweden)

    Prayitno Prayitno

    1997-12-01

    Full Text Available An immobilized microbial cell is a physical confinement or localization of intact cell to a certain defined region of space with the preservation of some desired catalytic activity. The immobilization cell process has been increasingly used, one of those is for waste water treatment industry. Microbial entrapping process one of the method for the microbial cell immobilization by using some carrier such as collagen, gelatin, alginate, carragena and cellulose tri acetat at the time being is commonly used. Immobilization cell is effective enough for waste water treatment containing toxic substance such as phenol and by using immobilization cell, secondary sedimentation tanks is no longer used.

  11. Immobilization of enzymes by radiation

    International Nuclear Information System (INIS)

    Kaetsu, I.; Kumakura, M.; Yoshida, M.; Asano, M.; Himei, M.; Tamura, M.; Hayashi, K.

    1979-01-01

    Immobilization of various enzymes was performed by radiation-induced polymerization of glass-forming monomers at low temperatures. Alpha-amylase and glucoamylase were effectively immobilized in hydrophilic polymer carrier such as poly(2-hydroxyethyl methacrylate) and also in rather hydrophobic carrier such as poly(tetraethylene-glycol diacrylate). Immobilized human hemoglobin underwent the reversible oxygenation concomitantly with change of oxygen concentration outside of the matrices. (author)

  12. On-line sequential injection-capillary electrophoresis for near-real-time monitoring of extracellular lactate in cell culture flasks.

    Science.gov (United States)

    Alhusban, Ala A; Gaudry, Adam J; Breadmore, Michael C; Gueven, Nuri; Guijt, Rosanne M

    2014-01-03

    Cell culture has replaced many in vivo studies because of ethical and regulatory measures as well as the possibility of increased throughput. Analytical assays to determine (bio)chemical changes are often based on end-point measurements rather than on a series of sequential determinations. The purpose of this work is to develop an analytical system for monitoring cell culture based on sequential injection-capillary electrophoresis (SI-CE) with capacitively coupled contactless conductivity detection (C(4)D). The system was applied for monitoring lactate production, an important metabolic indicator, during mammalian cell culture. Using a background electrolyte consisting of 25mM tris(hydroxymethyl)aminomethane, 35mM cyclohexyl-2-aminoethanesulfonic acid with 0.02% poly(ethyleneimine) (PEI) at pH 8.65 and a multilayer polymer coated capillary, lactate could be resolved from other compounds present in media with relative standard deviations 0.07% for intraday electrophoretic mobility and an analysis time of less than 10min. Using the human embryonic kidney cell line HEK293, lactate concentrations in the cell culture medium were measured every 20min over 3 days, requiring only 8.73μL of sample per run. Combining simplicity, portability, automation, high sample throughput, low limits of detection, low sample consumption and the ability to up- and outscale, this new methodology represents a promising technique for near real-time monitoring of chemical changes in diverse cell culture applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Histomorphometric analysis of the response of rat skeletal muscle to swimming, immobilization and rehabilitation

    Directory of Open Access Journals (Sweden)

    C.C.F. Nascimento

    2008-09-01

    Full Text Available The objective of the present study was to determine to what extent, if any, swimming training applied before immobilization in a cast interferes with the rehabilitation process in rat muscles. Female Wistar rats, mean weight 260.52 ± 16.26 g, were divided into 4 groups of 6 rats each: control, 6 weeks under baseline conditions; trained, swimming training for 6 weeks; trained-immobilized, swimming training for 6 weeks and then immobilized for 1 week; trained-immobilized-rehabilitated, swimming training for 6 weeks, immobilized for 1 week and then remobilized with swimming for 2 weeks. The animals were then sacrificed and the soleus and tibialis anterior muscles were dissected, frozen in liquid nitrogen and processed histochemically (H&E and mATPase. Data were analyzed statistically by the mixed effects linear model (P < 0.05. Cytoarchitectural changes such as degenerative characteristics in the immobilized group and regenerative characteristics such as centralized nucleus, fiber size variation and cell fragmentation in the groups submitted to swimming were more significant in the soleus muscle. The diameters of the lesser soleus type 1 and type 2A fibers were significantly reduced in the trained-immobilized group compared to the trained group (P < 0.001. In the tibialis anterior, there was an increase in the number of type 2B fibers and a reduction in type 2A fibers when trained-immobilized rats were compared to trained rats (P < 0.001. In trained-immobilized-rehabilitated rats, there was a reduction in type 2B fibers and an increase in type 2A fibers compared to trained-immobilized rats (P < 0.009. We concluded that swimming training did not minimize the deleterious effects of immobilization on the muscles studied and that remobilization did not favor tissue re-adaptation.

  14. The immobilization of filamentous fungi by cellular adherence and surface film growth on radiopolymerized hydrogels

    International Nuclear Information System (INIS)

    Petre, M.; Zarnea, G.; Adrian, P.; Gheorghiu, E.; Gheordunescu, V.

    1998-01-01

    The continuous biodegradation processes of cellulose wastes, from wine-producing industry and canned food processing were performed using immobilized fungal cells on complex polyhydrogels such as: collagen-polyacrylamide (CPAA), elastin-polyacrylamide (EPAA), gelatin-polyacrylamide (GPAA) and poly-hydroxy-ethyl-methyl-methacrylate (PHEMA) which were prepared by experimental radiopolymerization methods using a 60 Co radioactive source. The experiments were performed using cellulolytic micro- and macrofungal species and the immobilization methods were applied in connection with morphogenetic characteristics of each one of these species that were used as inoculum. A flow-cascade bioreactor was achieved as a research laboratory tool in order to control the cellulose waste biodegradation in continuous processes using immobilized fungal cells on complex polyhydrogels. In this way the continuous control was possible for fungal metabolic activity during the cellulose biodegradation processes by microscopical hyphal growth measurements inside the polyhydrogels and, also, by mycelial protein content analysis. The tested fungal species were Pleurotus ostreatus and Pleurotus florida from macromycetes and Trichoderma viride from micromycetes. There were noticed significant differences in biodegradation rate of cellulose wastes between 'in vitro' immobilized fungal cultures and free fungal cells cultures used as control samples to be compared with cellulose biodegradation processes in natural conditions of polluted ecosystems. The fungal growth displayed by soluble mycelial protein were compared with cellulose biodegradation rates which were expressed by cellulose weight loss in the culture medium. (authors)

  15. Enhanced accumulation of starch and total carbohydrates in alginate-immobilized Chlorella spp. induced by Azospirillum brasilense: II. Heterotrophic conditions.

    Science.gov (United States)

    Choix, Francisco J; de-Bashan, Luz E; Bashan, Yoav

    2012-10-10

    The effect of the bacterium Azospirillum brasilense jointly immobilized with Chlorella vulgaris or C. sorokiniana in alginate beads on total carbohydrates and starch was studied under dark and heterotrophic conditions for 144 h in synthetic growth medium supplemented with either d-glucose or Na-acetate as carbon sources. In all treatments, enhanced total carbohydrates and starch content per culture and per cell was obtained after 24h; only jointly immobilized C. vulgaris growing on d-glucose significantly increased total carbohydrates and starch content after 96 h. Enhanced accumulation of carbohydrate and starch under jointly immobilized conditions was variable with time of sampling and substrate used. Similar results occurred when the microalgae was immobilized alone. In both microalgae growing on either carbon sources, the bacterium promoted accumulation of carbohydrates and starch; when the microalgae were immobilized alone, they used the carbon sources for cell multiplication. In jointly immobilized conditions with Chlorella spp., affinity to carbon source and volumetric productivity and yield were higher than when Chlorella spp. were immobilized alone; however, the growth rate was higher in microalgae immobilized alone. This study demonstrates that under heterotrophic conditions, A. brasilense promotes the accumulation of carbohydrates in two strains Chlorella spp. under certain time-substrate combinations, producing mainly starch. As such, this bacterium is a biological factor that can change the composition of compounds in microalgae in dark, heterotrophic conditions. Copyright © 2012. Published by Elsevier Inc.

  16. Immobilized fluid membranes for gas separation

    Science.gov (United States)

    Liu, Wei; Canfield, Nathan L; Zhang, Jian; Li, Xiaohong Shari; Zhang, Jiguang

    2014-03-18

    Provided herein are immobilized liquid membranes for gas separation, methods of preparing such membranes and uses thereof. In one example, the immobilized membrane includes a porous metallic host matrix and an immobilized liquid fluid (such as a silicone oil) that is immobilized within one or more pores included within the porous metallic host matrix. The immobilized liquid membrane is capable of selective permeation of one type of molecule (such as oxygen) over another type of molecule (such as water). In some examples, the selective membrane is incorporated into a device to supply oxygen from ambient air to the device for electrochemical reactions, and at the same time, to block water penetration and electrolyte loss from the device.

  17. Gelatin Functionalization of Biomaterial Surfaces: Strategies for Immobilization and Visualization

    Directory of Open Access Journals (Sweden)

    Peter Dubruel

    2011-01-01

    Full Text Available In the present work, the immobilization of gelatin as biopolymer on two types of implantable biomaterials, polyimide and titanium, was compared. Both materials are known for their biocompatibility while lacking cell-interactive behavior. For both materials, a pre-functionalization step was required to enable gelatin immobilization. For the polyimide foils, a reactive succinimidyl ester was introduced first on the surface, followed by covalent grafting of gelatin. For the titanium material, methacrylate groups were first introduced on the Ti surface through a silanization reaction. The applied functionalities enabled the subsequent immobilization of methacrylamide modified gelatin. Both surface modified materials were characterized in depth using atomic force microscopy, static contact angle measurements, confocal fluorescence microscopy, attenuated total reflection infrared spectroscopy and X-ray photo-electron spectroscopy. The results indicated that the strategies elaborated for both material classes are suitable to apply stable gelatin coatings. Interestingly, depending on the material class studied, not all surface analysis techniques are applicable.

  18. Alkaline gel electrophoresis assay to detect DNA strand breaks and repair mechanisms in Escherichia coli

    International Nuclear Information System (INIS)

    Mattos, Jose Carlos Pelielo de; Motta, Ellen Serri da; Oliveira, Marcia Betania Nunes de; Dantas, Flavio Jose da Silva; Araujo, Adriano Caldeira de

    2008-01-01

    Reactive oxygen species (ROS) can induce lesions in different cellular targets, including DNA. Stannous chloride (SnCl 2 ) is a ROS generator, leading to lethality in Escherichia coli (E. coli), with the base excision repair (BER) mechanism playing a role in this process. Many techniques have been developed to detect genotoxicity, as comet assay, in eukaryotic cells, and plasmid DNA agarose gel electrophoresis. In this study, an adaptation of the alkaline gel electrophoresis method was carried out to ascertain the induction of strand breaks by SnCl 2 in bacterial DNA, from E. coli BER mutants, and its repair pathway. Results obtained show that SnCl 2 was able to induce DNA strand breaks in all strains tested. Moreover, endonuclease IV and exonuclease III play a role in DNA repair. On the whole, data has shown that the alkaline gel electrophoresis assay could be used both for studying DNA strand breaks induction and for associated repair mechanisms. (author)

  19. Alkaline gel electrophoresis assay to detect DNA strand breaks and repair mechanisms in Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Mattos, Jose Carlos Pelielo de; Motta, Ellen Serri da; Oliveira, Marcia Betania Nunes de; Dantas, Flavio Jose da Silva; Araujo, Adriano Caldeira de [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. de Biofisica e Biometria. Lab. de Radio e Fotobiologia]. E-mail: jcmattos@uerj.br

    2008-12-15

    Reactive oxygen species (ROS) can induce lesions in different cellular targets, including DNA. Stannous chloride (SnCl{sub 2}) is a ROS generator, leading to lethality in Escherichia coli (E. coli), with the base excision repair (BER) mechanism playing a role in this process. Many techniques have been developed to detect genotoxicity, as comet assay, in eukaryotic cells, and plasmid DNA agarose gel electrophoresis. In this study, an adaptation of the alkaline gel electrophoresis method was carried out to ascertain the induction of strand breaks by SnCl{sub 2} in bacterial DNA, from E. coli BER mutants, and its repair pathway. Results obtained show that SnCl{sub 2} was able to induce DNA strand breaks in all strains tested. Moreover, endonuclease IV and exonuclease III play a role in DNA repair. On the whole, data has shown that the alkaline gel electrophoresis assay could be used both for studying DNA strand breaks induction and for associated repair mechanisms. (author)

  20. Capillary electrophoresis: principles and applications in illicit drug analysis.

    Science.gov (United States)

    Tagliaro, F; Turrina, S; Smith, F P

    1996-02-09

    Capillary electrophoresis, which appeared in the early 1980s, is now rapidly expanding into many scientific disciplines, including analytical chemistry, biotechnology and biomedical and pharmaceutical sciences. In capillary electrophoresis,electrokinetic separations are carried out in tiny capillaries at high voltages (10-30 kV), thus obtaining high efficiencies (N > 10(5)) and excellent mass sensitivities (down to 10(-18)-10(-20) moles). The main features of capillary electrophoresis are: versatility of application (from inorganic ions to large DNA fragments), use of different separation modes with different selectivity, extremely low demands on sample volume, negligible running costs, possibility of interfacing with different detection systems, ruggedness and simplicity of instrumentation. Capillary electrophoresis applications in forensic sciences have appeared only recently, but are now rapidly growing, particularly in forensic toxicology. The present paper briefly describes the basic principles of capillary electrophoresis, from both the instrumental and analytical points of view. Furthermore, the main applications in the analysis of illicit/controlled drugs in both illicit preparations and biological samples are presented and discussed (43 references). It is concluded that the particular separation mechanism and the high complementarity of this technique to chromatography makes capillary electrophoresis a new powerful tool of investigation in the hands of forensic toxicologists.

  1. Electrophoresis in the analysis of natural and industrial ob ects

    International Nuclear Information System (INIS)

    Stepanov, A.V.; Korchemnaya, E.K.

    1979-01-01

    Given is a brief review on practical application of electrophoresis in the analysis of natural and industrial objects. Suggested are expressiVe methods of thorium, uranium and rare earth elements separation in minerals by electrophoresis. The possibility of quantitative determination of rare earth elements in meteorites by the method of electromigration is shown. By means of electrophoresis identified are forms of radioruthenium in a sea water. Shown is the electrophoresis application for reactor loop water analysis, for environment contamination study, for determination of some rare earth yield in reactions of uranium fission by heavy ions

  2. Improved methane removal in exhaust gas from biogas upgrading process using immobilized methane-oxidizing bacteria.

    Science.gov (United States)

    Sun, Meng-Ting; Yang, Zhi-Man; Fu, Shan-Fei; Fan, Xiao-Lei; Guo, Rong-Bo

    2018-05-01

    Methane in exhaust gas from biogas upgrading process, which is a greenhouse gas, could cause global warming. The biofilter with immobilized methane-oxidizing bacteria (MOB) is a promising approach for methane removal, and the selections of inoculated MOB culture and support material are vital for the biofilter. In this work, five MOB consortia were enriched at different methane concentrations. The MOB-20 consortium enriched at the methane concentration of 20.0% (v/v) was then immobilized on sponge and two particle sizes of volcanic rock in biofilters to remove methane in exhaust gas from biogas upgrading process. Results showed that the immobilized MOB performed more admirable methane removal capacity than suspended cells. The immobilized MOB on sponge reached the highest methane removal efficiency (RE) of 35%. The rough surface, preferable hydroscopicity, appropriate pore size and particle size of support material might favor the MOB immobilization and accordingly methane removal. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Polyelectrolyte Complex Beads by Novel Two-Step Process for Improved Performance of Viable Whole-Cell Baeyer-Villiger Monoxygenase by Immobilization

    Czech Academy of Sciences Publication Activity Database

    Krajčovič, T.; Bučko, M.; Vikartovská, A.; Lacík, I.; Uhelská, L.; Chorvát, D.; Neděla, Vilém; Tihlaříková, Eva; Gericke, M.; Heinze, T.; Gemeiner, P.

    2017-01-01

    Roč. 7, č. 11 (2017), s. 353-364 ISSN 2073-4344 Institutional support: RVO:68081731 Keywords : polyelectrolyte complex beads * environmental scanning electron microscopy * confocal laser scanning microscopy * Baeyer-Villiger biooxidation * cyclohexanone monoxygenase * immobilization * viable whole-cell biocatalyst Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering OBOR OECD: Bioprocessing technologies (industrial processes relying on biological agents to drive the process) biocatalysis, fermentation Impact factor: 3.082, year: 2016 http://www.mdpi.com/2073-4344/7/11/353

  4. Method for selective immobilization of macromolecules on self assembled monolayer surfaces

    Science.gov (United States)

    Laskin, Julia [Richland, WA; Wang, Peng [Billerica, MA

    2011-11-29

    Disclosed is a method for selective chemical binding and immobilization of macromolecules on solid supports in conjunction with self-assembled monolayer (SAM) surfaces. Immobilization involves selective binding of peptides and other macromolecules to SAM surfaces using reactive landing (RL) of mass-selected, gas phase ions. SAM surfaces provide a simple and convenient platform for tailoring chemical properties of a variety of substrates. The invention finds applications in biochemistry ranging from characterization of molecular recognition events at the amino acid level and identification of biologically active motifs in proteins, to development of novel biosensors and substrates for stimulated protein and cell adhesion.

  5. Mass transfer behavior in lactic acid fermentation using immobilized lactobacillus delbrueckii

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H.; Seki, M.; Furusaki, S. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering

    1995-08-20

    We performed simulation studies on mass transfer behavior for immobilized cells in lactic acid fermentation using the mathematical model developed previously. The simulations pointed to an unusual result; that lactate ion diffuses into the bead center from outside during the batch fermentation and the startup period of the continuous fermentation, whereas free lactic acid and protons diffuse in the opposite direction. This phenomenon is caused by the addition of base to keep pH constant in the broth. Also, using an appropriate buffer to control pH in the broth can reduce the inward diffusion of lactate ion and improve the productivity of lactic acid. A singular mass transfer phenomenon is expected to take place in other production processes using immobilized cells (or enzyme), where alkali solution is added to broth to keep pH constant. 9 refs., 6 figs.

  6. The application of single cell gel electrophoresis or comet assay to human monitoring studies Aplicacion de la electroforesis unicelular o ensayo cometa en estudios de monitoreo humano

    Directory of Open Access Journals (Sweden)

    Mahara Valverde

    1999-11-01

    Full Text Available Objective. In the search of new human genotoxic biomarkers, the single cell gel electrophoresis assay has been proposed as a sensible alternative. Material and methods. This technique detects principally single strand breaks as well as alkali-labile and repair-retarded sites. Results. Herein we present our experience using the single cell gel electrophoresis assay in human population studies, both occupationally and environmentally exposed. Conclusions. We discuss the assay feasibility as a genotoxic biomarker.Objetivo. En la búsqueda de nuevos marcadores genotóxicos aplicables a estudios de poblaciones humanas expuestos a xenobióticos, la utilización del ensayo de electroforesis en una sola célula se ha propuesto como un método sensible y una buena alternativa. Material y métodos. Esta técnica detecta rompimientos en el ADN de cadena sencilla, así como sitios álcali lábiles y sitios retardados de reparación. Resultados. En este trabajo, presentamos nuestra experiencia utilizando este ensayo en poblaciones humanas expuestas ocupacionalmente o ambientalmente a diferentes xenobióticos. Conclusiones. Se discute la posible utilidad de este ensayo como un biomarcador de efecto genotóxico.

  7. Remote handling in the Plutonium Immobilization Project: Plutonium conversion and first stage immobilization

    International Nuclear Information System (INIS)

    Brault, J.R.

    2000-01-01

    Since the break up of the Soviet Union at the end of the Cold War, the United States and Russia have been negotiating ways to reduce their nuclear stockpiles. Economics is one of the reasons behind this, but another important reason is safeguarding these materials from unstable organizations and countries. With the downsizing of the nuclear stockpiles, large quantities of plutonium are being declared excess and must be safely disposed of. The Savannah River Site (SRS) has been selected as the site where the immobilization facility will be located. Conceptual design and process development commenced in 1998. SRS will immobilize excess plutonium in a ceramic waste form and encapsulate it in vitrified high level waste in the Defense Waste Processing Facility (DWPF) canister. These canisters will then be interred in the national repository at Yucca Mountain, New Mexico. The facility is divided into three distinct operating areas: Plutonium Conversion, First Stage Immobilization, and Second Stage Immobilization. This paper will discuss the first two operations

  8. Continuous ethanol production using yeast immobilized on sugar-cane stalks

    Energy Technology Data Exchange (ETDEWEB)

    Vasconcelos, J.N. de [Alagoas Univ., Maceio, AL (Brazil). Dept. de Engenharia Quimica]. E-mail: jnunes@ctec.ufal.br; Lopes, C.E. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Antibioticos; Franca, F.P. de [Universidade Federal, Rio de Janeiro, RJ (Brazil). Escola de Quimica. Dept. de Engenharia Bioquimica

    2004-09-01

    Sugar-cane stalks, 2.0 cm long, were used as a support for yeast immobilization envisaging ethanol production. The assays were conducted in 38.5 L fermenters containing a bed of stalks with 50% porosity. The operational stability of the immobilized yeast, the efficiency and stability of the process, as well as the best dilution rate were evaluated. Molasses from demerara sugar production was used in the medium formulation. It was diluted to obtain 111.75 {+-} 1.51 g/L without any further treatment. Sulfuric acid was used to adjust the pH value to around 4.2. Every two days Kamoran HJ (10 ppm) or with a mixture containing penicillin (10 ppm) and tetracycline (10 ppm), was added to the medium. Ethanol yield and efficiency were 29.64 g/L.h and 86.40%, respectively, and the total reducing sugars conversion was 74.61% at a dilution rate of 0.83 h{sup -1}. The yeast-stalk system was shown to be stable for over a 60 day period at extremely variable dilution rates ranging from 0.05 h{sup -1} to 3.00 h{sup -1}. The concentration of immobilized cell reached around 109 cells/gram of dry sugar-cane stalk when the fermenter was operating at the highest dilution rate (3.00 h{sup -1}). (author)

  9. Ocular Proteomics with Emphasis on Two-Dimensional Gel Electrophoresis and Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Honoré Bent

    2010-01-01

    Full Text Available Abstract The intention of this review is to provide an overview of current methodologies employed in the rapidly developing field of ocular proteomics with emphasis on sample preparation, two-dimensional polyacrylamide gel electrophoresis (2D-PAGE and mass spectrometry (MS. Appropriate sample preparation for the diverse range of cells and tissues of the eye is essential to ensure reliable results. Current methods of protein staining for 2D-PAGE, protein labelling for two-dimensional difference gel electrophoresis, gel-based expression analysis and protein identification by MS are summarised. The uses of gel-free MS-based strategies (MuDPIT, iTRAQ, ICAT and SILAC are also discussed. Proteomic technologies promise to shed new light onto ocular disease processes that could lead to the discovery of strong novel biomarkers and therapeutic targets useful in many ophthalmic conditions.

  10. Degradation of TCE using sequential anaerobic biofilm and aerobic immobilized bed reactor

    Science.gov (United States)

    Chapatwala, Kirit D.; Babu, G. R. V.; Baresi, Larry; Trunzo, Richard M.

    1995-01-01

    Bacteria capable of degrading trichloroethylene (TCE) were isolated from contaminated wastewaters and soil sites. The aerobic cultures were identified as Pseudomonas aeruginosa (four species) and Pseudomonas fluorescens. The optimal conditions for the growth of aerobic cultures were determined. The minimal inhibitory concentration values of TCE for Pseudomonas sps. were also determined. The aerobic cells were immobilized in calcium alginate in the form of beads. Degradation of TCE by the anaerobic and dichloroethylene (DCE) by aerobic cultures was studied using dual reactors - anaerobic biofilm and aerobic immobilized bed reactor. The minimal mineral salt (MMS) medium saturated with TCE was pumped at the rate of 1 ml per hour into the anaerobic reactor. The MMS medium saturated with DCE and supplemented with xylenes and toluene (3 ppm each) was pumped at the rate of 1 ml per hour into the fluidized air-uplift-type reactor containing the immobilized aerobic cells. The concentrations of TCE and DCE and the metabolites formed during their degradation by the anaerobic and aerobic cultures were monitored by GC. The preliminary study suggests that the anaerobic and aerobic cultures of our isolates can degrade TCE and DCE.

  11. Immobilization needs and technology programs

    International Nuclear Information System (INIS)

    Gray, L.W.; Kan, T.; Shaw, H.; Armantrout, G.

    1995-01-01

    In the aftermath of the Cold War, the US and Russia agreed to large reductions in nuclear weapons. To aid in the selection of long-term management options, DOE has undertaken a multifaceted study to select options for storage and disposition of plutonium in keeping with US policy that plutonium must be subjected to the highest standards of safety, security, and accountability. One alternative being considered is immobilization. To arrive at a suitable immobilization form, we first reviewed published information on high-level waste immobilization technologies and identified 72 possible plutonium immobilization forms to be prescreened. Surviving forms were further screened using multi-attribute utility analysis to determine the most promising technology families. Promising immobilization families were further evaluated to identify chemical, engineering, environmental, safety, and health problems that remain to be solved prior to making technical decisions as to the viability of using the form for long- term disposition of plutonium. From this evaluation, a detailed research and development plan has been developed to provide answers to these remaining questions

  12. Biodiesel production with immobilized lipase: A review.

    Science.gov (United States)

    Tan, Tianwei; Lu, Jike; Nie, Kaili; Deng, Li; Wang, Fang

    2010-01-01

    Fatty acid alkyl esters, also called biodiesel, are environmentally friendly and show great potential as an alternative liquid fuel. Biodiesel is produced by transesterification of oils or fats with chemical catalysts or lipase. Immobilized lipase as the biocatalyst draws high attention because that process is "greener". This article reviews the current status of biodiesel production with immobilized lipase, including various lipases, immobilization methods, various feedstocks, lipase inactivation caused by short chain alcohols and large scale industrialization. Adsorption is still the most widely employed method for lipase immobilization. There are two kinds of lipase used most frequently especially for large scale industrialization. One is Candida antartica lipase immobilized on acrylic resin, and the other is Candida sp. 99-125 lipase immobilized on inexpensive textile membranes. However, to further reduce the cost of biodiesel production, new immobilization techniques with higher activity and stability still need to be explored. Copyright 2010 Elsevier Inc. All rights reserved.

  13. Rejoining of DNA double-strand breaks in X-irradiated CHO cells studied by constant- and graded-field gel electrophoresis

    International Nuclear Information System (INIS)

    Dahm-Daphi, J.; Dikomey, E.

    1996-01-01

    Induction and repair of double-strand breaks (dsb) were measured in exponentially growing CHO-10A cells using the constant- and graded-field gel electrophoresis. Dsb repair was studied after an X-ray dose of 60Gy. The repair curve obtained was biphasic with the respective half-times of τ 1 = 3.8 ± 0.9 and τ 2 = 118 ± 30 min. The number of non-reparable dsb was measured for X-ray doses up to 180 Gy and was found to be only a small fraction (14%) of all non-rejoinable breaks determined previously using the alkaline unwinding technique. The ratio of non-reparable dsb to the number of lethal events calculated from survival curves is 0.14:1. This result indicates that for CHO cells non-reparable dsb represent only a small fraction of lethal damage. This is in line with the cytogenic observation that cell killing mainly results from mis-rejoined events (i.e. exchange aberrations, translocations, interstitial delections). The kinetics of dsb rejoining were found to be independent of the size of the fragments involved (between 1 and 10 Mbp). In addition, the rejoining kinetics of DNA fragments ≤ 1 Mbp did not show the formation of new DNA fragments with time after irradiation indicating the absence of programmed cell death in irradiated CHO cells. (author)

  14. An Improved 2-Dimensional Gel Electrophoresis Method for Resolving Human Erythrocyte Membrane Proteins.

    Science.gov (United States)

    Kumar, Manoj; Singh, Rajendra; Meena, Anil; Patidar, Bhagwan S; Prasad, Rajendra; Chhabra, Sunil K; Bansal, Surendra K

    2017-01-01

    The 2-dimensional gel electrophoresis (2-DE) technique is widely used for the analysis of complex protein mixtures extracted from biological samples. It is one of the most commonly used analytical techniques in proteomics to study qualitative and quantitative protein changes between different states of a cell or an organism (eg, healthy and diseased), conditionally expressed proteins, posttranslational modifications, and so on. The 2-DE technique is used for its unparalleled ability to separate thousands of proteins simultaneously. The resolution of the proteins by 2-DE largely depends on the quality of sample prepared during protein extraction which increases results in terms of reproducibility and minimizes protein modifications that may result in artifactual spots on 2-DE gels. The buffer used for the extraction and solubilization of proteins influences the quality and reproducibility of the resolution of proteins on 2-DE gel. The purification by cleanup kit is another powerful process to prevent horizontal streaking which occurs during isoelectric focusing due to the presence of contaminants such as salts, lipids, nucleic acids, and detergents. Erythrocyte membrane proteins serve as prototypes for multifunctional proteins in various erythroid and nonerythroid cells. In this study, we therefore optimized the selected major conditions of 2-DE for resolving various proteins of human erythrocyte membrane. The modification included the optimization of conditions for sample preparation, cleanup of protein sample, isoelectric focusing, equilibration, and storage of immobilized pH gradient strips, which were further carefully examined to achieve optimum conditions for improving the quality of protein spots on 2-DE gels. The present improved 2-DE analysis method enabled better detection of protein spots with higher quality and reproducibility. Therefore, the conditions established in this study may be used for the 2-DE analysis of erythrocyte membrane proteins for

  15. Analysis of electrophoresis performance

    Science.gov (United States)

    Roberts, G. O.

    1984-01-01

    The SAMPLE computer code models electrophoresis separation in a wide range of conditions. Results are included for steady three dimensional continuous flow electrophoresis (CFE), time dependent gel and acetate film experiments in one or two dimensions and isoelectric focusing in one dimension. The code evolves N two dimensional radical concentration distributions in time, or distance down a CFE chamber. For each time or distance increment, there are six stages, successively obtaining the pH distribution, the corresponding degrees of ionization for each radical, the conductivity, the electric field and current distribution, and the flux components in each direction for each separate radical. The final stage is to update the radical concentrations. The model formulation for ion motion in an electric field ignores activity effects, and is valid only for low concentrations; for larger concentrations the conductivity is, therefore, also invalid.

  16. Designing photobioreactors based on living cells immobilized in silica gel for carbon dioxide mitigation.

    Science.gov (United States)

    Rooke, Joanna C; Léonard, Alexandre; Meunier, Christophe F; Su, Bao-Lian

    2011-09-19

    Atmospheric carbon dioxide levels have been rising since the industrial revolution, with the most dramatic increase occurring since the end of World War II. Carbon dioxide is widely regarded as one of the major factors contributing to the greenhouse effect, which is of major concern in today's society because it leads to global warming. Photosynthesis is Nature's tool for combating elevated carbon dioxide levels. In essence, photosynthesis allows a cell to harvest solar energy and convert it into chemical energy through the assimilation of carbon dioxide and water. Therefore photosynthesis is regarded as an ideal way to harness the abundance of solar energy that reaches Earth and convert anthropologically generated carbon dioxide into useful carbohydrates, providing a much more sustainable energy source. This Minireview aims to tackle the idea of immobilizing photosynthetic unicellular organisms within inert silica frameworks, providing protection both to the fragile cells and to the external ecosystem, and to use this resultant living hybrid material in a photobioreactor. The viability and activity of various unicellular organisms are summarized alongside design issues of a photobioreactor based on living hybrid materials. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. ADJUVANT PROPERTIES OF NANOPARTICLES IMMOBILIZED RECOMBINANT DIPHTHERIA TOXOID FRAGMENT

    Directory of Open Access Journals (Sweden)

    T. O. Chudina

    2017-08-01

    Full Text Available The aim of the research was to compare the characteristics of nanoparticles with different chemical structure and size (colloidal gold Gold 1 and Gold 2, calcium phosphate CaP and poly(lactideco-glykolid PLGA 1 and 2 to find the most efficient carriers of antigen — recombinant diphtheria toxoid for per os immunization. According to the MTT test, all studied particles show no significant cytotoxic impact on the studied cells in vitro, with the exception of CaP nanoparticles, which in high concentrations have cytotoxic effect on the U937 cells, and Gold nanoparticles 1 and 2, that are able to inhibit growth of the L929 cells. The most effective phagocytosis by macrophage-like cells J774 is observed for PLGA nanoparticles 1 and 2 with the immobilized antigen, while Gold nanoparticles 1 and 2 with antigen can interact with the surface of these cells without being phagocytated by them. In BALB/c mice immunized per os with antigen immobilized on PLGA 1 and 2 as well as Gold 2 carriers, the concentration of specific IgA antibodies in blood significantly increases after the second immunization, compared with controls. In the group of mice treated with PLGA 2 conjugated antigen, the concentration of specific IgG in blood after the third immunization also increases. These results show the promise of nanoparticles PLGA 1 and 2 as adjuvant for immunization per os.

  18. Preparative electrophoresis of industrial fission product solutions

    International Nuclear Information System (INIS)

    Tret, Joel

    1971-07-01

    The aim of this work is to contribute to the development of the continuous electrophoresis technique while studying its application in the preparative electrophoresis of industrial fission product solutions. The apparatus described is original. It was built for the purposes of the investigation and proved very reliable in operation. The experimental conditions necessary to maintain and supervise the apparatus in a state of equilibrium are examined in detail; their stability is an important factor, indispensable to the correct performance of an experiment. By subjecting an industrial solution of fission products to preparative electrophoresis it is possible, according to the experimental conditions, to prepare carrier-free radioelements of radiochemical purity (from 5 to 7 radioelements): 137 Cs, 90 Sr, 141+144 Ce, 91 Y, 95 Nb, 95 Zr, 103+106 Ru. (author) [fr

  19. Images of gel electrophoresis - RGP caps | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us RGP caps Images of gel electrophoresis Data detail Data name Images of gel electrophoresis D...OI 10.18908/lsdba.nbdc00318-05-002 Description of data contents Detailed information and images of gel electrophoresis... of each marker. Data file File name: rgp_caps_electrophoresis_image.zip File URL: ftp://ftp.biosc...iencedbc.jp/archive/rgp-caps/LATEST/rgp_caps_electrophoresis_image.zip File size:... 28.7 MB Simple search URL - Data acquisition method Gel electrophoresis Data analysis method STS markers :

  20. A comparative study of radiation induced DNA damage and repair in buccal cells and lymphocytes assessed by single cell gel electrophoresis (comet) assay

    International Nuclear Information System (INIS)

    Dhillon, V.S.; Fenech, M.

    2003-01-01

    Full text: During the past few years, there has been increasing interest in epithelial cells from buccal mucosa for genotoxicity evaluation of different chemical and/or physical agents. In the present study we used the buccal and sublingual epithelial cells to detect both inter- and intra-individual variation in radiation induced DNA damage and repair. For this purpose we used the single cell gel electrophoresis assay which over the years has gained wide spread acceptance as a simple, sensitive and reliable assay to measure genotoxicity related effects as well as kinetics of DNA repair. Buccal and sublingual epithelial cells from six individuals (3 male and 3 females; 35-45 years old) were collected. Cells were then irradiated for 0, 2 and 4 Gy doses using 137 Cs-source (5.58 Gy min-1). After irradiation the cells were either placed immediately on ice or incubated at 37 deg C for 2 1/2 hour to allow cellular repair. We also studied G0 and G1 lymphocytes from the same individuals to compare the radiation-induced DNA damage and repair potential with the two types of buccal cells. Baseline DNA damage rate was significantly greater (p < 0.001) in buccal (28.18%) and sublingual epithelial cells (30.66) as compared to G0 (22.02%) and G1 (21.46%) lymphocytes. Radiation-induced DNA damage in buccal (19.34%, 2Gy; 21.41%, 4 Gy) and sublingual epithelial cells (18.11% and 20.60%) was very similar and significantly lower than that observed in lymphocytes (29.76%, 56.77% for G0 and 32.66%, 59.32% for G1). The extent of DNA repair in buccal and sublingual epithelial cells was significantly lower than that observed in lymphocytes. The results for buccal and sublingual epithelial cells were highly correlated with each other (r 0.9541) as were those of G0 and G1 lymphocytes (r 0.9868). The results suggest a much reduced capacity for cellular repair in buccal and sublingual epithelial cells

  1. Enhanced compatibility of chemically modified titanium surface with periodontal ligament cells

    International Nuclear Information System (INIS)

    Kado, T.; Hidaka, T.; Aita, H.; Endo, K.; Furuichi, Y.

    2012-01-01

    Highlights: ► Cell-adhesive molecules were covalently immobilized on a Ti surface. ► Immobilized cell-adhesive molecules maintained native function on the Ti surface. ► Immobilized collagen enhanced adhesion of periodontal ligament cells to the Ti. - Abstract: A simple chemical modification method was developed to immobilize cell-adhesive molecules on a titanium surface to improve its compatibility with human periodontal ligament cells (HPDLCs).The polished titanium disk was immersed in 1% (v/v) p-vinylbenzoic acid solution for 2 h to introduce carboxyl groups onto the surface. After rinsing with distilled deionized water, the titanium disk was dipped into 1.47% 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide solution containing 0.1 mg/ml Gly-Arg-Gly-Asp-Ser (GRGDS), human plasma fibronectin (pFN), or type I collagen from calf skin (Col) to covalently immobilize the cell-adhesive molecules on the titanium surface via formation of peptide bonds. X-ray photoelectron spectroscopy analyses revealed that cell-adhesive molecules were successfully immobilized on the titanium surfaces. The Col-immobilized titanium surface revealed higher values regarding nano rough characteristics than the as-polished titanium surface under scanning probe microscopy. The number of HPDLCs attached to both the pFN- and Col-immobilized titanium surfaces was twice that attached to the as-polished titanium surfaces. The cells were larger with the cellular processes that stretched to a greater extent on the pFN- and Col-immobilized titanium surfaces than on the as-polished titanium surface (p < 0.05). HPDLCs on the Col-immobilized titanium surfaces showed more extensive expression of vinculin at the tips of cell projections and more contiguously along the cell outline than on the as-polished, GRGDS-immobilized and pFN-immobilized titanium surfaces. It was concluded that cell-adhesive molecules successfully immobilized on the titanium surface and improved the compatibility of the surface

  2. Biodegradation of chlorobenzene using immobilized crude extracts ...

    African Journals Online (AJOL)

    SERVER

    2007-10-04

    Oct 4, 2007 ... immobilized crude extracts were reused for all other experiments and found that immobilization .... India which are of analytical reagent grade. .... 9. 60. 3. 1. Figure 3. Degradation of chlorobenzene by immobilized crude.

  3. Tilted hexagonal post arrays: DNA electrophoresis in anisotropic media.

    Science.gov (United States)

    Chen, Zhen; Dorfman, Kevin D

    2014-02-01

    Using Brownian dynamics simulations, we show that DNA electrophoresis in a hexagonal array of micron-sized posts changes qualitatively when the applied electric field vector is not coincident with the lattice vectors of the array. DNA electrophoresis in such "tilted" post arrays is superior to the standard "un-tilted" approach; while the time required to achieve a resolution of unity in a tilted post array is similar to an un-tilted array at a low-electric field strengths, this time (i) decreases exponentially with electric field strength in a tilted array and (ii) increases exponentially with electric field strength in an un-tilted array. Although the DNA dynamics in a post array are complicated, the electrophoretic mobility results indicate that the "free path," i.e. the average distance of ballistic trajectories of point-sized particles launched from random positions in the unit cell until they intersect the next post, is a useful proxy for the detailed DNA trajectories. The analysis of the free path reveals a fundamental connection between anisotropy of the medium and DNA transport therein that goes beyond simply improving the separation device. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Immobilized/P25/DSAT and Immobilized/Kronos/DSAT on Photocatalytic Degradation of Reactive Red 4 Under Fluorescent Light

    Directory of Open Access Journals (Sweden)

    Azami M. S.

    2016-01-01

    Full Text Available In this work, photocatalytic degradation of Reactive Red 4 (RR4 using immobilized P25 and kronos were performed under fluorescent light sources. The photocatalysis activity for both catalysts was investigated under fluorescent lamp source which consist UV and Visible light. The effect of various parameters such as initial concentration, initial pH and strenght of immobilized plate were studied. The result showed that 90% of RR4 dye was degrade in 1 hr using immobilized/kronos/DSAT at 100 mg L-1 of RR4 dye while 81% degradation was achieved by immobilized/P25/DSAT at the same condition. The lowest pH showed the higher photocatalytic activity. Hence, the effect of dye concentration and pH on the photocatalysis study can be related with the behavior of environmental pollution. The low strength showed by immobilized/P25/DSAT where it remain 37 % as compared with strength of immobilized/kronos/DSAT (52 wt.%. For the future work, the polymer binder like Polyvinyl alcohol (PVA, Polyethylene glycol (PEG, and others polymers can be apply in immobilized study to overcome the strength problem.

  5. Repeated batch cultivation of the hydrocarbon-degrading, micro-algal strain Prototheca zopfii RND16 immobilized in polyurethane foam.

    Science.gov (United States)

    Ueno, Ryohei; Wada, Shun; Urano, Naoto

    2008-01-01

    This study reports on the stability of the cells of a heterotrophic green micro-algal strain Prototheca zopfii RND16 immobilized in polyurethane foam (PUF) cubes during degradation of mixed hydrocarbon substrate, which was composed of n-alkanes and polycyclic aromatic hydrocarbons (PAHs), in 5 successive cycles of repeated batch cultivation at 30 degrees C. Both RND16 cells and mixed hydrocarbon substrate components had been entrapped in PUF cubes through cultivation. PUF-immobilized RND16 degraded n-alkanes almost completely, whereas the strain hardly degraded PAHs in PUFs, rather they accumulated in the matrices. It is noteworthy that this result is strikingly different from that of the free-living cell culture, where RND16 reduced concentrations of both n-alkanes and PAHs. However, PAHs accumulation in the PUFs did not impair the performance of the immobilized alga to utilize n-alkanes. These results suggest that the PUFs harboring RND16 cells could be used repeatedly for selective retrieval of PAHs from oil-polluted waters after preferential biodegradation of n-alkanes by algae.

  6. Gel Electrophoresis on a Budget to Dye for

    Science.gov (United States)

    Yu, Julie H.

    2010-01-01

    Gel electrophoresis is one of the most important tools used in molecular biology and has facilitated the entire field of genetic engineering by enabling the separation of nucleic acids and proteins. However, commercial electrophoresis kits can cost up to $800 for each setup, which is cost prohibitive for most classroom budgets. This article…

  7. In vitro and in vivo invasiveness of different pulsed-field get electrophoresis types of Listeria monocytogenes

    DEFF Research Database (Denmark)

    Larsen, Charlotte Nexmann; Nørrung, Birgit; Sommer, Helle Mølgaard

    2002-01-01

    The virulence of different pulsed-field gel electrophoresis (PFGE) types of Listeria monocytogenes was examined by monitoring their ability to invade Caco-2 cells. Strains belonging to seven different PFGE types originating from both foods and humans were included. No significant differences...

  8. Detoxification of Corncob Acid Hydrolysate with SAA Pretreatment and Xylitol Production by Immobilized Candida tropicalis

    Science.gov (United States)

    Deng, Li-Hong; Tang, Yong; Liu, Yun

    2014-01-01

    Xylitol fermentation production from corncob acid hydrolysate has become an attractive and promising process. However, corncob acid hydrolysate cannot be directly used as fermentation substrate owing to various inhibitors. In this work, soaking in aqueous ammonia (SAA) pretreatment was employed to reduce the inhibitors in acid hydrolysate. After detoxification, the corncob acid hydrolysate was fermented by immobilized Candida tropicalis cell to produce xylitol. Results revealed that SAA pretreatment showed high delignification and efficient removal of acetyl group compounds without effect on cellulose and xylan content. Acetic acid was completely removed, and the content of phenolic compounds was reduced by 80%. Furthermore, kinetic behaviors of xylitol production by immobilized C. tropicalis cell were elucidated from corncob acid hydrolysate detoxified with SAA pretreatment and two-step adsorption method, respectively. The immobilized C. tropicalis cell showed higher productivity efficiency using the corncob acid hydrolysate as fermentation substrate after detoxification with SAA pretreatment than by two-step adsorption method in the five successive batch fermentation rounds. After the fifth round fermentation, about 60 g xylitol/L fermentation substrate was obtained for SAA pretreatment detoxification, while about 30 g xylitol/L fermentation substrate was obtained for two-step adsorption detoxification. PMID:25133211

  9. Electron tomography of cryo-immobilized plant tissue: a novel approach to studying 3D macromolecular architecture of mature plant cell walls in situ.

    Directory of Open Access Journals (Sweden)

    Purbasha Sarkar

    Full Text Available Cost-effective production of lignocellulosic biofuel requires efficient breakdown of cell walls present in plant biomass to retrieve the wall polysaccharides for fermentation. In-depth knowledge of plant cell wall composition is therefore essential for improving the fuel production process. The precise spatial three-dimensional (3D organization of cellulose, hemicellulose, pectin and lignin within plant cell walls remains unclear to date since the microscopy techniques used so far have been limited to two-dimensional, topographic or low-resolution imaging, or required isolation or chemical extraction of the cell walls. In this paper we demonstrate that by cryo-immobilizing fresh tissue, then either cryo-sectioning or freeze-substituting and resin embedding, followed by cryo- or room temperature (RT electron tomography, respectively, we can visualize previously unseen details of plant cell wall architecture in 3D, at macromolecular resolution (∼ 2 nm, and in near-native state. Qualitative and quantitative analyses showed that wall organization of cryo-immobilized samples were preserved remarkably better than conventionally prepared samples that suffer substantial extraction. Lignin-less primary cell walls were well preserved in both self-pressurized rapidly frozen (SPRF, cryo-sectioned samples as well as high-pressure frozen, freeze-substituted and resin embedded (HPF-FS-resin samples. Lignin-rich secondary cell walls appeared featureless in HPF-FS-resin sections presumably due to poor stain penetration, but their macromolecular features could be visualized in unprecedented details in our cryo-sections. While cryo-tomography of vitreous tissue sections is currently proving to be instrumental in developing 3D models of lignin-rich secondary cell walls, here we confirm that the technically easier method of RT-tomography of HPF-FS-resin sections could be used immediately for routine study of low-lignin cell walls. As a proof of principle, we

  10. Immobilized anaerobic fermentation for bio-fuel production by Clostridium co-culture.

    Science.gov (United States)

    Xu, Lei; Tschirner, Ulrike

    2014-08-01

    Clostridium thermocellum/Clostridium thermolacticum co-culture fermentation has been shown to be a promising way of producing ethanol from several carbohydrates. In this research, immobilization techniques using sodium alginate and alkali pretreatment were successfully applied on this co-culture to improve the bio-ethanol fermentation performance during consolidated bio-processing (CBP). The ethanol yield obtained increased by over 60 % (as a percentage of the theoretical maximum) as compared to free cell fermentation. For cellobiose under optimized conditions, the ethanol yields were approaching about 85 % of the theoretical efficiency. To examine the feasibility of this immobilization co-culture on lignocellulosic biomass conversion, untreated and pretreated aspen biomasses were also used for fermentation experiments. The immobilized co-culture shows clear benefits in bio-ethanol production in the CBP process using pretreated aspen. With a 3-h, 9 % NaOH pretreatment, the aspen powder fermentation yields approached 78 % of the maximum theoretical efficiency, which is almost twice the yield of the untreated aspen fermentation.

  11. DNA DAMAGE QUANTITATION BY ALKALINE GEL ELECTROPHORESIS.

    Energy Technology Data Exchange (ETDEWEB)

    SUTHERLAND,B.M.; BENNETT,P.V.; SUTHERLAND, J.C.

    2004-03-24

    Physical and chemical agents in the environment, those used in clinical applications, or encountered during recreational exposures to sunlight, induce damages in DNA. Understanding the biological impact of these agents requires quantitation of the levels of such damages in laboratory test systems as well as in field or clinical samples. Alkaline gel electrophoresis provides a sensitive (down to {approx} a few lesions/5Mb), rapid method of direct quantitation of a wide variety of DNA damages in nanogram quantities of non-radioactive DNAs from laboratory, field, or clinical specimens, including higher plants and animals. This method stems from velocity sedimentation studies of DNA populations, and from the simple methods of agarose gel electrophoresis. Our laboratories have developed quantitative agarose gel methods, analytical descriptions of DNA migration during electrophoresis on agarose gels (1-6), and electronic imaging for accurate determinations of DNA mass (7-9). Although all these components improve sensitivity and throughput of large numbers of samples (7,8,10), a simple version using only standard molecular biology equipment allows routine analysis of DNA damages at moderate frequencies. We present here a description of the methods, as well as a brief description of the underlying principles, required for a simplified approach to quantitation of DNA damages by alkaline gel electrophoresis.

  12. Identification of Increased Amounts of Eppin Protein Complex Components in Sperm Cells of Diabetic and Obese Individuals by Difference Gel Electrophoresis*

    Science.gov (United States)

    Paasch, Uwe; Heidenreich, Falk; Pursche, Theresia; Kuhlisch, Eberhard; Kettner, Karina; Grunewald, Sonja; Kratzsch, Jürgen; Dittmar, Gunnar; Glander, Hans-Jürgen; Hoflack, Bernard; Kriegel, Thomas M.

    2011-01-01

    Metabolic disorders like diabetes mellitus and obesity may compromise the fertility of men and women. To unveil disease-associated proteomic changes potentially affecting male fertility, the proteomes of sperm cells from type-1 diabetic, type-2 diabetic, non-diabetic obese and clinically healthy individuals were comparatively analyzed by difference gel electrophoresis. The adaptation of a general protein extraction procedure to the solubilization of proteins from sperm cells allowed for the resolution of 3187 fluorescent spots in the difference gel electrophoresis image of the master gel, which contained the entirety of solubilized sperm proteins. Comparison of the pathological and reference proteomes by applying an average abundance ratio setting of 1.6 and a p ≤ 0.05 criterion resulted in the identification of 79 fluorescent spots containing proteins that were present at significantly changed levels in the sperm cells. Biometric evaluation of the fluorescence data followed by mass spectrometric protein identification revealed altered levels of 12, 71, and 13 protein species in the proteomes of the type-1 diabetic, type-2 diabetic, and non-diabetic obese patients, respectively, with considerably enhanced amounts of the same set of one molecular form of semenogelin-1, one form of clusterin, and two forms of lactotransferrin in each group of pathologic samples. Remarkably, β-galactosidase-1-like protein was the only protein that was detected at decreased levels in all three pathologic situations. The former three proteins are part of the eppin (epididymal proteinase inhibitor) protein complex, which is thought to fulfill fertilization-related functions, such as ejaculate sperm protection, motility regulation and gain of competence for acrosome reaction, whereas the putative role of the latter protein to function as a glycosyl hydrolase during sperm maturation remains to be explored at the protein/enzyme level. The strikingly similar differences detected in the

  13. Improved immobilization of laccase on a glassy carbon electrode by oriented covalent attachment

    Directory of Open Access Journals (Sweden)

    Liu Xin

    2014-01-01

    Full Text Available A laccase from Thermus thermophilus HB27 was reported to be potentially useful in the design of a temperature controlled biofuel cell. For enhancing its application in different thermal conditions, we engineered a laccase-oriented immobilized electrode. A site-directed mutant N323C of the laccase was constructed. A photometric assay was employed in order to compare the catalytic properties of wild-type laccase and mutant. The mutant was attached to a glass carbon electrode by covalent cross-linking. The electrochemical properties of the immobilized laccase were investigated by cyclic voltammetry. This immobilization allowed the active electrode to function at temperatures up to 95°C. The thermal and pH dependence profiles were similar to those of the soluble enzyme investigated by spectrophotometry.

  14. Study of Streptavidin-Modified Quantum Dots by Capillary Electrophoresis

    Czech Academy of Sciences Publication Activity Database

    Stanisavljevic, M.; Janů, L.; Šmerková, K.; Křížková, S.; Pizúrová, Naděžda; Ryvolová, M.; Adam, V.; Hubálek, J.; Kizek, R.

    2013-01-01

    Roč. 76, 7-8 (2013), s. 335-343 ISSN 0009-5893 Institutional support: RVO:68081723 Keywords : Capillary electrophoresis * Gel electrophoresis * Avidin-biotin technology * Oligonucleotide * Nanoparticle * quantum dots Subject RIV: CE - Biochemistry Impact factor: 1.370, year: 2013

  15. Characterization of agarose as immobilization matrix model for a microbial biosensor

    Directory of Open Access Journals (Sweden)

    Pernetti Mimma

    2003-01-01

    Full Text Available Microbial biosensors are promising tools for the detection of specific substances in different fields, such as environmental, biomedical, food or agricultural. They allow rapid measurements, no need for complex sample preparation or specialized personnel and easy handling. In order to enhance the managing, miniaturization and stability of the biosensor and to prevent cell leaching, bacteria immobilization is desirable. A systematic characterization procedure to choose a suitable immobilization method and matrix, was proposed in this study. Physical properties, storage stability mass transport phenomena and biocompatibility were evaluated, employing agarose as the model matrix. Preliminary essays with bioluminescent bacteria detecting Tributyltin were also carried out.

  16. Heat stress-induced loss of eukaryotic initiation factor 5A (eIF-5A) in a human pancreatic cancer cell line, MIA PaCa-2, analyzed by two-dimensional gel electrophoresis.

    Science.gov (United States)

    Takeuchi, Kana; Nakamura, Kazuyuki; Fujimoto, Masanori; Kaino, Seiji; Kondoh, Satoshi; Okita, Kiwamu

    2002-02-01

    Alterations of intracellular proteins during the process of heat stress-induced cell death of a human pancreatic cancer cell line, MIA PaCa-2, were investigated using two-dimensional gel electrophoresis (2-DE), agarose gel electrophoresis, and cell biology techniques. Incubation of MIA PaCa-2 at 45 degrees C for 30 min decreased the cell growth rate and cell viability without causing chromosomal DNA fragmentation. Incubation at 51 degrees C for 30 min suppressed cell growth and again led to death without DNA fragmentation. The cell death was associated with the loss of an intracellular protein of M(r) 17,500 and pI 5.2 on 2-DE gel. This protein was determined to be eukaryotic initiation factor SA (eIF-5A) by microsequencing of the N-terminal region of peptide fragments obtained by cyanogen bromide treatment of the protein blotted onto a polyvinylidene difluoride (PVDF) membrane. The sequences detected were QXSALRKNGFVVLKGRP and STSKTGXHGHAKVHLVGID, which were homologous with the sequence of eIF-5A from Gln 20 to Pro 36 and from Ser 43 to Asp 61, respectively. Furthermore, the result of sequencing suggested that the protein was an active form of hypusinated eIF-5A, because Lys 46 could be detected but not Lys 49, which is the site for hypusination. These results suggest that loss of the active form of eIF-5A is an important factor in the irreversible process of heat stress-induced death of MIA PaCa-2 cells.

  17. Integration of amperometric sensors for microchip capillary electrophoresis application

    International Nuclear Information System (INIS)

    Dicorato, F; Moore, E; Glennon, J

    2011-01-01

    Capillary electrophoresis is a technique for the separation and analysis of chemical compounds. Techniques adopted from the microchip technology knowledge have led to recent developments of electrophoresis system with integration on microchip. Microchip Capillary Electrophoresis (μCE) systems offer a series of advantages as easy integration for Lab-on-a-chip applications, high performance, portability, speed, minimal solvent and sample requirements. A new technological challenge aims at the development of an economic modular microchip capillary electrophoresis systems using separable and independent units concerning the sensor. In this project we worked on the development of an interchangeable amperometric sensor in order to provide a solution to such electrode passivation and facilitating the use of tailored sensors for specific analyte detection besides. Fluidic chips have been machined from cyclic olefin polymer pallets (Zeonor) using a micro-injection molding machine.

  18. Integration of amperometric sensors for microchip capillary electrophoresis application

    Energy Technology Data Exchange (ETDEWEB)

    Dicorato, F; Moore, E [Life Sciences Interface Group, Tyndall National Institute, Lee Maltings, Dyke Parade, Cork (Ireland); Glennon, J, E-mail: eric.moore@tyndall.ie [Chemistry Department, University College Cork, College Road, Cork (Ireland)

    2011-08-17

    Capillary electrophoresis is a technique for the separation and analysis of chemical compounds. Techniques adopted from the microchip technology knowledge have led to recent developments of electrophoresis system with integration on microchip. Microchip Capillary Electrophoresis ({mu}CE) systems offer a series of advantages as easy integration for Lab-on-a-chip applications, high performance, portability, speed, minimal solvent and sample requirements. A new technological challenge aims at the development of an economic modular microchip capillary electrophoresis systems using separable and independent units concerning the sensor. In this project we worked on the development of an interchangeable amperometric sensor in order to provide a solution to such electrode passivation and facilitating the use of tailored sensors for specific analyte detection besides. Fluidic chips have been machined from cyclic olefin polymer pallets (Zeonor) using a micro-injection molding machine.

  19. Design-Only Conceptual Design Report: Plutonium Immobilization Plant

    International Nuclear Information System (INIS)

    DiSabatino, A.; Loftus, D.

    1999-01-01

    This design-only conceptual design report was prepared to support a funding request by the Department of Energy Office of Fissile Materials Disposition for engineering and design of the Plutonium Immobilization Plant, which will be used to immobilize up to 50 tonnes of surplus plutonium. The siting for the Plutonium Immobilization Plant will be determined pursuant to the site-specific Surplus Plutonium Disposition Environmental Impact Statement in a Plutonium Deposition Record of Decision in early 1999. This document reflects a new facility using the preferred technology (ceramic immobilization using the can-in-canister approach) and the preferred site (at Savannah River). The Plutonium Immobilization Plant accepts plutonium from pit conversion and from non-pit sources and, through a ceramic immobilization process, converts the plutonium into mineral-like forms that are subsequently encapsulated within a large canister of high-level waste glass. The final immobilized product must make the plutonium as inherently unattractive and inaccessible for use in nuclear weapons as the plutonium in spent fuel from commercial reactors and must be suitable for geologic disposal. Plutonium immobilization at the Savannah River Site uses: (1) A new building, the Plutonium Immobilization Plant, which will convert non-pit surplus plutonium to an oxide form suitable for the immobilization process, immobilize plutonium in a titanate-based ceramic form, place cans of the plutonium-ceramic forms into magazines, and load the magazines into a canister; (2) The existing Defense Waste Processing Facility for the pouring of high-level waste glass into the canisters; and (3) The Actinide Packaging and Storage Facility to receive and store feed materials. The Plutonium Immobilization Plant uses existing Savannah River Site infra-structure for analytical laboratory services, waste handling, fire protection, training, and other support utilities and services. The Plutonium Immobilization Plant

  20. Ceramic protective coatings applied by sol-gel or electrophoresis

    International Nuclear Information System (INIS)

    Stoch, A.

    1993-01-01

    Sol-gel and electrophoresis are the complementary techniques which may be used for obtaining the ceramic coatings. The composition of such a coatings depends on the composition of electrophoresis bath or sol solution. Thermal treatment is used for densifying the coating and promoting the adherence of coating to the substrate. In presented work silica, silica-alumina or alumina coatings are applied by sol-gel dip coating procedure on steel, aluminium or ceramic substrates. Electrophoresis is employed for obtaining zirconia, alumina or hydroxyapatite coatings on stainless steel. (author). 7 refs

  1. Management of immobilization and its complication for elderly.

    Science.gov (United States)

    Laksmi, Purwita W; Harimurti, Kuntjoro; Setiati, Siti; Soejono, Czeresna H; Aries, Wanarani; Roosheroe, Arya Govinda

    2008-10-01

    Increased life expectancy have an effect on the rising percentage of elderly population in Indonesia and health problem associated with the elderly, particularly immobilization. Immobilization may cause various complications, especially when it has been overlooked without any appropriate and proper medical care in keeping with the procedures. High incidence of immobilization in elderly and the life-threatening complication call for an agreement on management of immobilization and its complication. Management of immobilization needs interdisciplinary team-work cooperation, the patients and their family. The management may be commenced through a complete geriatric review, formulating functional goals and constructing therapeutic plan. Various medical conditions and external factors that may act as risk factors of immobilization as well as drugs intake that may exaggerate the immobilization should be evaluated and optimally managed. Any complication due to immobilization and other concomitant disease/condition should be recognized and managed comprehensively in order to reduce morbidity and mortality. Management of immobilization and its complications include pharmacological and non-pharmacological treatment, i.e. various mobility exercises, utilization of ambulatory device and supporting appliance for assisting patients in stand-up position, as well as the management of urinary voiding and defecation.

  2. Excess Weapons Plutonium Immobilization in Russia

    International Nuclear Information System (INIS)

    Jardine, L.; Borisov, G.B.

    2000-01-01

    The joint goal of the Russian work is to establish a full-scale plutonium immobilization facility at a Russian industrial site by 2005. To achieve this requires that the necessary engineering and technical basis be developed in these Russian projects and the needed Russian approvals be obtained to conduct industrial-scale immobilization of plutonium-containing materials at a Russian industrial site by the 2005 date. This meeting and future work will provide the basis for joint decisions. Supporting R and D projects are being carried out at Russian Institutes that directly support the technical needs of Russian industrial sites to immobilize plutonium-containing materials. Special R and D on plutonium materials is also being carried out to support excess weapons disposition in Russia and the US, including nonproliferation studies of plutonium recovery from immobilization forms and accelerated radiation damage studies of the US-specified plutonium ceramic for immobilizing plutonium. This intriguing and extraordinary cooperation on certain aspects of the weapons plutonium problem is now progressing well and much work with plutonium has been completed in the past two years. Because much excellent and unique scientific and engineering technical work has now been completed in Russia in many aspects of plutonium immobilization, this meeting in St. Petersburg was both timely and necessary to summarize, review, and discuss these efforts among those who performed the actual work. The results of this meeting will help the US and Russia jointly define the future direction of the Russian plutonium immobilization program, and make it an even stronger and more integrated Russian program. The two objectives for the meeting were to: (1) Bring together the Russian organizations, experts, and managers performing the work into one place for four days to review and discuss their work with each other; and (2) Publish a meeting summary and a proceedings to compile reports of all the

  3. Radiation immobilization of catalase and its application

    International Nuclear Information System (INIS)

    Wang Guanghui; Ha Hongfei; Wang Xia; Wu Jilan

    1988-01-01

    Catalase was immobilized by a chemical method on porous polyacrylamide particles produced by radiation polymerization of acrylamide monomer at low temperature (-78 0 C). Activity of immobilized catalase was enhanced distinctly by joining a chemical arm to the support. The method of recovery of catalase activity on immobilized polymer was found by soaking it in certain buffer. The treatment of H 2 O 2 both in aqueous solution and alcoholic solution by using the immobilized catalase was performed. (author)

  4. Production of cellulase and xylanase in a bubble gum column using immobilized Aspergillus niger KKS

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Seong-Woo; Kim, Seung-Woo [Univ. of Suwon (Korea, Republic of); Lee, Jin-Suk [Korea Institute of Energy Research, Daejeon (Korea, Republic of)

    1995-05-01

    Aspergillus niger KKS, isolated from a farmland near Suwon, was immobilized on Celite and polyurethane foams. Enzyme activities produced by the immobilized cell system in a bubble column were higher than that of shake-flask culture. The enzyme productivities were twice as high. {Beta}-Glucosidase, {Beta}-xylosidase, and xylanase activities obtained in a bubble column were significant when the ground rice straw was used as a substrate. 9 refs., 2 figs., 3 tabs.

  5. Batch Fermentative Biohydrogen Production Process Using Immobilized Anaerobic Sludge from Organic Solid Waste

    Directory of Open Access Journals (Sweden)

    Patrick T. Sekoai

    2016-12-01

    Full Text Available This study examined the potential of organic solid waste for biohydrogen production using immobilized anaerobic sludge. Biohydrogen was produced under batch mode at process conditions of 7.9, 30.3 °C and 90 h for pH, temperature and fermentation time, respectively. A maximum biohydrogen fraction of 48.67%, which corresponded to a biohydrogen yield of 215.39 mL H2/g Total Volatile Solids (TVS, was achieved. Therefore, the utilization of immobilized cells could pave the way for a large-scale biohydrogen production process.

  6. Bioelectrochemistry of non-covalent immobilized alcohol dehydrogenase on oxidized diamond nanoparticles.

    Science.gov (United States)

    Nicolau, Eduardo; Méndez, Jessica; Fonseca, José J; Griebenow, Kai; Cabrera, Carlos R

    2012-06-01

    Diamond nanoparticles are considered a biocompatible material mainly due to their non-cytotoxicity and remarkable cellular uptake. Model proteins such as cytochrome c and lysozyme have been physically adsorbed onto diamond nanoparticles, proving it to be a suitable surface for high protein loading. Herein, we explore the non-covalent immobilization of the redox enzyme alcohol dehydrogenase (ADH) from Saccharomyces cerevisiae (E.C.1.1.1.1) onto oxidized diamond nanoparticles for bioelectrochemical applications. Diamond nanoparticles were first oxidized and physically characterized by X-ray diffraction (XRD), FT-IR and TEM. Langmuir isotherms were constructed to investigate the ADH adsorption onto the diamond nanoparticles as a function of pH. It was found that a higher packing density is achieved at the isoelectric point of the enzyme. Moreover, the relative activity of the immobilized enzyme on diamond nanoparticles was addressed under optimum pH conditions able to retain up to 70% of its initial activity. Thereafter, an ethanol bioelectrochemical cell was constructed by employing the immobilized alcohol dehydrogenase onto diamond nanoparticles, this being able to provide a current increment of 72% when compared to the blank solution. The results of this investigation suggest that this technology may be useful for the construction of alcohol biosensors or biofuel cells in the near future. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Radioactive seed immobilization techniques for interstitial brachytherapy

    International Nuclear Information System (INIS)

    Yan, K.; Podder, T.; Buzurovic, I.; Hu, Y.; Dicker, A.; Valicenti, R.; Yu, Y.; Messing, E.; Rubens, D.; Sarkar, N.; Ng, W.

    2008-01-01

    In prostate brachytherapy, seeds can detach from their deposited sites and move locally in the pelvis or migrate to distant sites including the pulmonary and cardiac regions. Undesirable consequences of seed migration include inadequate dose coverage of the prostate and tissue irradiation effects at the site of migration. Thus, it is clinically important to develop seed immobilization techniques. We first analyze the possible causes for seed movement, and propose three potential techniques for seed immobilization: (1) surgical glue, (2) laser coagulation and (3) diathermy coagulation. The feasibility of each method is explored. Experiments were carried out using fresh bovine livers to investigate the efficacy of seed immobilization using surgical glue. Results have shown that the surgical glue can effectively immobilize the seeds. Evaluation of the radiation dose distribution revealed that the non-immobilized seed movement would change the planned isodose distribution considerably; while by using surgical glue method to immobilize the seeds, the changes were negligible. Prostate brachytherapy seed immobilization is necessary and three alternative mechanisms are promising for addressing this issue. Experiments for exploring the efficacy of the other two proposed methods are ongoing. Devices compatible with the brachytherapy procedure will be designed in future. (orig.)

  8. Evaluation of genotoxicity after application of Listerine(R) on human lymphocytes by micronucleus and single cell gel electrophoresis assays.

    Science.gov (United States)

    Türkez, Hasan; Togar, Basak; Arabaci, Taner

    2012-04-01

    Listerine (LN) is one of the most commonly used mouth rinses worldwide although very limited information is available concerning its genotoxicity. In another view, the biological safety profile of oral care products is frequently assumed on the basis of simplistic test models. Therefore, the present study was undertaken to investigate the in vitro genotoxic potential of LN using micronucleus and single cell gel electrophoresis tests as genetic endpoints. Different concentrations of LN (0-100% of ml/culture, v/v) were applied to whole human blood cultures (n = 5). The result of the present study showed that there were no statistically significant differences (p > 0.05) between the control group and the groups treated with LN alone in both analysed endpoints. In conclusion, our result first demonstrated the absence of genotoxicity of LN on human lymphocytes.

  9. Characteristics of Immobilized Urease on Grafted Alginate Bead Systems

    Directory of Open Access Journals (Sweden)

    Enas N. Danial

    2015-04-01

    Full Text Available This study evaluated the biological importance of immobilized urease enzyme over the free urease. The support material used for urease immobilization was alginate. Generally, the immobilization of urease in alginate gel showed a marked increase in Km and Vmax. However, the immobilized urease showed higher thermal stability than that of free enzyme. The rate of thermal inactivation of the immobilized enzyme decreased due to entrapment in gel matrix. Also, the activity of the immobilized urease was more stable in retention than that of the free enzyme during the storage in solution, although the activity of the immobilized enzyme was lower in comparison with the free enzyme. A stable immobilized system and long storage life are convenient for applications that would not be feasible with a soluble enzyme system. These results highlighted the technical and biochemical benefits of immobilized urease over the free enzyme.

  10. Detection of clonal T-cell receptor beta and gamma chain gene rearrangement by polymerase chain reaction and capillary gel electrophoresis.

    Science.gov (United States)

    Fan, Hongxin; Robetorye, Ryan S

    2013-01-01

    Although established diagnostic criteria exist for mature T-cell neoplasms, a definitive diagnosis of a T-cell lymphoproliferative disorder cannot always be obtained using more conventional techniques such as flow cytometric immunophenotyping, conventional cytogenetics, fluorescence in situ hybridization, or immunohistochemistry. However, because T-cell malignancies contain identically rearranged T-cell receptor gamma (TCRG) and/or beta (TCRB) genes, the polymerase chain reaction (PCR) can be a fast, convenient, and dependable option to identify clonal T-cell processes. This chapter describes the use of PCR and capillary electrophoresis to identify clonal TCRB and TCRG gene rearrangements (TCRB and TCRG PCR) using a commercially available method employing multiple multiplex PCR tubes that was originally developed as the result of a large European BIOMED-2 collaborative study (Invivoscribe Technologies). The core protocol for the TCRB assay involves the use of three separate multiplex master mix tubes. Tubes A and B target the framework regions within the variable and joining regions of the TCRB gene, and Tube C targets the diversity and joining regions of the TCRB gene. The core protocol for the TCRG assay utilizes two multiplex master mix tubes (Tubes A and B) that target the variable and joining regions of the TCRG gene. Use of the five BIOMED-2 TCRB and TCRG PCR multiplex tubes in parallel can detect approximately 94% of clonal TCR gene rearrangements.

  11. Immobilization of IFR salt wastes in mortar

    International Nuclear Information System (INIS)

    Fischer, D.F.; Johnson, T.R.

    1988-01-01

    Portland cement-base mortars are being considered for immobilizing chloride salt wastes produced by the fuel cycles of Integral Fast Reactors (IFR). The IFR is a sodium-cooled fast reactor with metal alloy fuels. It has a close-coupled fuel cycle in which fission products are separated from the actinides in an electrochemical cell operating at 500/degree/C. This cell has a liquid cadmium anode in which the fuels are dissolved and a liquid salt electrolyte. The salt will be a mixture of either lithium, potassium, and sodium chlorides or lithium, calcium, barium, and sodium chlorides. One method being considered for immobilizing the treated nontransuranic salt waste is to disperse the salt in a portland cement-base mortar that will be sealed in corrosion-resistant containers. For this application, the grout must be sufficiently fluid that it can be pumped into canister-molds where it will solidify into a strong, leach-resistant material. The set times must be longer than a few hours to allow sufficient time for processing, and the mortar must reach a reasonable compressive strength (/approximately/7 MPa) within three days to permit handling. Because fission product heating will be high, about 0.6 W/kg for a mortar containing 10% waste salt, the effects of elevated temperatures during curing and storage on mortar properties must be considered

  12. Potential of capillary electrophoresis for the profiling of propolis

    NARCIS (Netherlands)

    Hilhorst, M.J; Somsen, G.W; de Jong, G.J.

    1998-01-01

    The usefulness of capillary electrophoresis (CE) with diode array detection for the profiling of Propolis, a hive product, is investigated. Water extracts of Propolis were analyzed with both capillary zone electrophoresis (CZE) at pH 7.0 and 9.3, and micellar electrokinetic chromatography (MEKC)

  13. Immobilization and characterization of inulinase from Ulocladium

    Indian Academy of Sciences (India)

    Ulocladium atrum inulinase was immobilized on different composite membranes composed of chitosan/nonwoven fabrics. Km values of free and immobilized U. atrum inulinase on different composite membranes were calculated. The enzyme had optimum pH at 5.6 for free and immobilized U. atrum inulinase on polyester ...

  14. Treatment and immobilization of intermediate level radioactive wastes

    International Nuclear Information System (INIS)

    Lerch, R.E.; Greenhalgh, W.O.; Partridge, J.A.; Richardson, G.L.

    1977-01-01

    This paper discusses a new program underway to develop and demonstrate treatment and immobilization technologies for intermediate level wastes (ILW) generated in the nuclear fuel cycle. Initial work has defined the sources, quantities and types of wastes which comprise ILW. Laboratory studies are underway to define treatment technologies for liquid ILW which contains volatile contaminants and to define immobilization parameters for the residues resulting from treatment of ILW. Immobilization agents initially being evaluated for the various residues include cement, urea-formaldehyde, and bitumen although other immobilization agents will be studied. The program also includes development of acceptable test procedures for the final immobilized products as well as development of proposed criteria for storage, transportation, and disposal of the immobilized ILW. 20 figures, 10 tables

  15. Serum protein fractionation using supported molecular matrix electrophoresis.

    Science.gov (United States)

    Dong, Weijie; Matsuno, Yu-ki; Kameyama, Akihiko

    2013-08-01

    Supported molecular matrix electrophoresis (SMME), in which a hydrophilic polymer such as PVA serves as a support within a porous PVDF membrane, was recently developed. This method is similar to cellulose acetate membrane electrophoresis but differs in the compatibility to glycan analysis of the separated bands. In this report, we describe the first instance of the application of SMME to human serum fractionation, and demonstrate the differences with serum fractionation by cellulose acetate membrane electrophoresis. The SMME membrane exhibited almost no EOF during electrophoresis, unlike the cellulose acetate membrane, but afforded comparative results for serum fractionation. The visualization of each fraction was achieved by conventional staining with dye such as Direct Blue-71, and objective quantification was obtained by densitometry after inducing membrane transparency with 1-nonene. Immunostaining was also achieved. Moreover, mass spectrometric analysis of both N-linked and O-linked glycans from the separated bands was demonstrated. Serum fractionation and glycan profiling of each fraction using SMME will enable novel insights into the relationships between various glycosylation profiles and disease states. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Immobilization patterns and dynamics of acetate-utilizing methanogens in sterile granular sludge from upflow anaerobic sludge blanket (UASB) reactors

    DEFF Research Database (Denmark)

    Schmidt, Jens Ejbye; Ahring, Birgitte Kiær

    1999-01-01

    Sterile granular sludge was inoculated with either Methanosarcina mazeii S-6, Methanosaeta concilii GP-6, or both species in acetate-fea upflow anaerobic sludge blanket (UASB) reactors to investigate the immobilization patterns and dynamics of aceticlastic methanogens in granular sludge. After......, but where the acetate concentration was low this strain was immobilized on support material as single cells or small clumps, The data clearly show that the two aceticlastic methanogens immobilize differently in UASB systems, depending on the conditions found throughout the UASB reactor....

  17. Airlift bioreactor containing chitosan-immobilized Sphingobium sp. P2 for treatment of lubricants in wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Khondee, Nichakorn; Tathong, Sitti [International Postgraduate Programs in Environmental Management, Graduate School, Chulalongkorn University, Bangkok (Thailand); Bioremediation Research Unit, Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok (Thailand); Pinyakong, Onruthai [Bioremediation Research Unit, Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok (Thailand); National Center of Excellence for Environmental and Hazardous Waste Management (NCE-EHWM), Chulalongkorn University, Bangkok (Thailand); Powtongsook, Sorawit [Center of Excellence for Marine Biotechnology (c/o Department of Marine Science, Chulalongkorn University), National Center for Genetic Engineering and Biotechnology, Pathum Thani (Thailand); Chatchupong, Thawach; Ruangchainikom, Chalermchai [Environmental Research and Management Department, PTT Research and Technology Institute, Ayutthaya (Thailand); Luepromchai, Ekawan, E-mail: ekawan.l@chula.ac.th [Bioremediation Research Unit, Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok (Thailand); National Center of Excellence for Environmental and Hazardous Waste Management (NCE-EHWM), Chulalongkorn University, Bangkok (Thailand)

    2012-04-30

    Highlights: Black-Right-Pointing-Pointer Sphingobium sp. P2 effectively degraded various lubricant samples. Black-Right-Pointing-Pointer Efficiency of Sphingobium sp. P2 increased after immobilization on chitosan. Black-Right-Pointing-Pointer High removal efficiency was due to both sorption and degradation processes. Black-Right-Pointing-Pointer The immobilized bacteria (4 g L{sup -1}) were applied in internal loop airlift bioreactor. Black-Right-Pointing-Pointer The bioreactor continuously removed lubricant from emulsified wastewater. - Abstract: An internal loop airlift bioreactor containing chitosan-immobilized Sphingobium sp. P2 was applied for the removal of automotive lubricants from emulsified wastewater. The chitosan-immobilized bacteria had higher lubricant removal efficiency than free and killed-immobilized cells because they were able to sorp and degrade the lubricants simultaneously. In a semi-continuous batch experiment, the immobilized bacteria were able to remove 80-90% of the 200 mg L{sup -1} total petroleum hydrocarbons (TPH) from both synthetic and carwash wastewater. The internal loop airlift bioreactor, containing 4 g L{sup -1} immobilized bacteria, was later designed and operated at 2.0 h HRT (hydraulic retention time) for over 70 days. At a steady state, the reactor continuously removed 85 {+-} 5% TPH and 73 {+-} 11% chemical oxygen demand (COD) from the carwash wastewater with 25-200 mg L{sup -1} amended lubricant. The internal loop airlift reactor's simple operation and high stability demonstrate its high potential for use in treating lubricants in emulsified wastewater from carwashes and other industries.

  18. Airlift bioreactor containing chitosan-immobilized Sphingobium sp. P2 for treatment of lubricants in wastewater

    International Nuclear Information System (INIS)

    Khondee, Nichakorn; Tathong, Sitti; Pinyakong, Onruthai; Powtongsook, Sorawit; Chatchupong, Thawach; Ruangchainikom, Chalermchai; Luepromchai, Ekawan

    2012-01-01

    Highlights: ► Sphingobium sp. P2 effectively degraded various lubricant samples. ► Efficiency of Sphingobium sp. P2 increased after immobilization on chitosan. ► High removal efficiency was due to both sorption and degradation processes. ► The immobilized bacteria (4 g L −1 ) were applied in internal loop airlift bioreactor. ► The bioreactor continuously removed lubricant from emulsified wastewater. - Abstract: An internal loop airlift bioreactor containing chitosan-immobilized Sphingobium sp. P2 was applied for the removal of automotive lubricants from emulsified wastewater. The chitosan-immobilized bacteria had higher lubricant removal efficiency than free and killed-immobilized cells because they were able to sorp and degrade the lubricants simultaneously. In a semi-continuous batch experiment, the immobilized bacteria were able to remove 80–90% of the 200 mg L −1 total petroleum hydrocarbons (TPH) from both synthetic and carwash wastewater. The internal loop airlift bioreactor, containing 4 g L −1 immobilized bacteria, was later designed and operated at 2.0 h HRT (hydraulic retention time) for over 70 days. At a steady state, the reactor continuously removed 85 ± 5% TPH and 73 ± 11% chemical oxygen demand (COD) from the carwash wastewater with 25–200 mg L −1 amended lubricant. The internal loop airlift reactor's simple operation and high stability demonstrate its high potential for use in treating lubricants in emulsified wastewater from carwashes and other industries.

  19. Preliminary study on biological dosimetry using alkaline single cell gel electrophoresis of human peripheral lymphocytes

    International Nuclear Information System (INIS)

    Liu Qingjie; Lu Xue; Feng Jiangbing; Chen Deqing; Chen Xiaosui

    2006-01-01

    Objective: To explore the feasibility of alkaline single cell gel electrophoresis (SCGE) in biological dosimetry of ionizing radiation. Methods: Normal peripheral blood samples from two healthy males were exposed to different doses coblat-60 gamma-rays, ranged from 0 to 5 Gy, and the tail length (TL) and Oliver tail moment (TM) of the lymphocytes were analyzed with SCGE. The dose-effect curves of TL and TM were fitted respectively. The TL and TM of lymphocytes for eight radiation workers were analyzed with SCGE, cumulative doses were estimated using the fitted TL and TM equations, and then compared with the recorded monitoring doses. Results: The TLs or TMs of normal human lymphocytes were increased with the irradiation doses, and its relationship can be fitted with a linear-quadratic equations: Y=13.59 + 20.87X - 2.27 X 2 for TL, and Y = 8.50 + 15.04X - 1.43X 2 for TM, respectively (Y denotes TL or TM value, X is radiation dose). The doses estimated with TM equation were closer to the recorded monitoring doses than that with TL equation. Conclusions: The TM in lymphocytes analyzed with SCGE is a promising radiation biological dosimeter. (authors)

  20. Procedures for two-dimensional electrophoresis of proteins

    Energy Technology Data Exchange (ETDEWEB)

    Tollaksen, S.L.; Giometti, C.S.

    1996-10-01

    High-resolution two-dimensional gel electrophoresis (2DE) of proteins, using isoelectric focusing in the first dimension and sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS-PAGE) in the second, was first described in 1975. In the 20 years since those publications, numerous modifications of the original method have evolved. The ISO-DALT system of 2DE is a high-throughput approach that has stood the test of time. The problem of casting many isoelectric focusing gels and SDS-PAGE slab gels (up to 20) in a reproducible manner has been solved by the use of the techniques and equipment described in this manual. The ISO-DALT system of two-dimensional gel electrophoresis originated in the late 1970s and has been modified many times to improve its high-resolution, high-throughput capabilities. This report provides the detailed procedures used with the current ISO-DALT system to prepare, run, stain, and photograph two-dimensional gels for protein analysis.

  1. Nitric Acid-Treated Carbon Fibers with Enhanced Hydrophilicity for Candida tropicalis Immobilization in Xylitol Fermentation

    Directory of Open Access Journals (Sweden)

    Le Wang

    2016-03-01

    Full Text Available Nitric acid (HNO3-treated carbon fiber (CF rich in hydrophilic groups was applied as a cell-immobilized carrier for xylitol fermentation. Using scanning electron microscopy, we characterized the morphology of the HNO3-treated CF. Additionally, we evaluated the immobilized efficiency (IE of Candida tropicalis and xylitol fermentation yield by investigating the surface properties of nitric acid treated CF, specifically, the acidic group content, zero charge point, degree of moisture and contact angle. We found that adhesion is the major mechanism for cell immobilization and that it is greatly affected by the hydrophilic–hydrophilic surface properties. In our experiments, we found 3 hto be the optimal time for treating CF with nitric acid, resulting in an improved IE of Candida tropicalis of 0.98 g∙g−1 and the highest xylitol yield and volumetric productivity (70.13% and 1.22 g∙L−1∙h−1, respectively. The HNO3-treated CF represents a promising method for preparing biocompatible biocarriers for multi-batch fermentation.

  2. Comparative study between yeasts immobilized on alumina beads and on membranes prepared by two routes

    Directory of Open Access Journals (Sweden)

    Kiyohara Pedro K.

    2003-01-01

    Full Text Available Alumina channeled beads and rough surface membranes prepared from aqueous sols of fibrillar pseudoboehmite are able to immobilize yeasts for ethanol fermentation of sugar solutions. This paper describes comparative results of assays carried out with yeasts immobilized onto alpha-alumina beads and membranes prepared under two different conditions of processing and firing. The fermentation tests evaluated by the decrease of fermentable sugars, referred as Brix degrees per hour, indicated that the yeasts immobilized on beads had similar performance, probably because their surfaces, even being morphologically different, presented the same value of open porosity. One type of membrane (asymmetrical; precursor: pseudoboehmite; firing temperature 1,150ºC; crystal structure; alpha-alumina had better performance than the other type (asymmetrical; precursor: fibrillar pseudoboehmite plus aluminum hydroxiacetate mixture; 1,150ºC; alpha-alumina because the yeast cells entered into their porous interior through the surface slits, were immobilized and their growth was easier than on the external surface.

  3. Detoxification of Corncob Acid Hydrolysate with SAA Pretreatment and Xylitol Production by Immobilized Candida tropicalis

    Directory of Open Access Journals (Sweden)

    Li-Hong Deng

    2014-01-01

    Full Text Available Xylitol fermentation production from corncob acid hydrolysate has become an attractive and promising process. However, corncob acid hydrolysate cannot be directly used as fermentation substrate owing to various inhibitors. In this work, soaking in aqueous ammonia (SAA pretreatment was employed to reduce the inhibitors in acid hydrolysate. After detoxification, the corncob acid hydrolysate was fermented by immobilized Candida tropicalis cell to produce xylitol. Results revealed that SAA pretreatment showed high delignification and efficient removal of acetyl group compounds without effect on cellulose and xylan content. Acetic acid was completely removed, and the content of phenolic compounds was reduced by 80%. Furthermore, kinetic behaviors of xylitol production by immobilized C. tropicalis cell were elucidated from corncob acid hydrolysate detoxified with SAA pretreatment and two-step adsorption method, respectively. The immobilized C. tropicalis cell showed higher productivity efficiency using the corncob acid hydrolysate as fermentation substrate after detoxification with SAA pretreatment than by two-step adsorption method in the five successive batch fermentation rounds. After the fifth round fermentation, about 60 g xylitol/L fermentation substrate was obtained for SAA pretreatment detoxification, while about 30 g xylitol/L fermentation substrate was obtained for two-step adsorption detoxification.

  4. Clinical Relevance of Trace Bands on Serum Electrophoresis in Patients Without a History of Gammopathy

    Science.gov (United States)

    Gwathmey, TanYa M.; Willis, Monte S.; Tatreau, Jason; Wang, Shaobin; McCudden, Christopher R.

    2015-01-01

    Serum protein electrophoresis (SPE) and immunofixation is commonly used to screen for plasma cell dyscrasias. Interpretation of these tests is qualitative by nature and can yield trace, faint, or scarcely visible immunoglobulin bands (TFS), which can be difficult to classify. Whether these bands should be reported at all is challenging given their unknown clinical significance. In the present study, we retrospectively analyzed 14,036 physician-ordered protein SPE and immunofixation electrophoresis (IFE) tests on serum and urine specimens (from 4,091 patients) during the period of 2000-2010. We found that 17% of all IFE results evaluated for the presence of monoclonal gammopathies (2,389 out of 14,036) contained TFS bands, representing 4.2% (173 out of 4091) of all patients evaluated. Sixty of these patients (42%) had no previous history of gammopathy, and were clinically evaluated over a mean period of up to five years from the original diagnosis of plasma cell pathology. None of these patients had progressed to multiple myeloma, lymphoplasmacytic lymphoma, plasmacytoma, or leukemia. The remaining 82 patients (58%) had a previous history of gammopathy, but had not progressed to any symptomatic plasma cell dyscrasia. Evaluation of these patients was followed for a median period of 4.3 years, with a mean of 21.5 IFE tests per individual. These data suggest that for patients without a previous history of gammopathy, the presence of TFS bands on serum protein electrophoresis does not warrant frequent follow up investigation as commonly practiced. Routine follow up of patients with a prior history of gammopathy, conversely, are warranted and may contribute to overall survival with multiple treatment options now available. For those interpreting IFE results, it may be worth considering these data when composing comments regarding suggested repeat testing frequency by SPE/IFE or alternate test methods. PMID:27683487

  5. Basic study for gas cleaning using discharge and electrophoresis

    International Nuclear Information System (INIS)

    Su, Zhen-Zhou; Sawada, Jun; Takashima, Kazunori; Katsura, Shinji; Mizuno, Akira

    2004-01-01

    A NO x removal method using discharge plasma and electrophoresis for exhaust control was studied. The 65-50% of NO was oxidized to NO 2 or HNO 3 by the discharge plasma with specific input energy of 45J/l. The electrophoresis was carried out to concentrate the NO 2 or HNO 3 adsorbed on the adsorbents. As a result, 80% of the adsorbed nitrate ions were found in the anode region. A combination of molecular sieve pellets of 13X and glass fiber cloth was tested for the collection of nitrate ions. The ability of simultaneous concentration of nitrate ions and sulfate ions using electrophoresis was examined

  6. Lipase immobilization and production of fatty acid methyl esters from canola oil using immobilized lipase

    International Nuclear Information System (INIS)

    Yuecel, Yasin; Demir, Cevdet; Dizge, Nadir; Keskinler, Buelent

    2011-01-01

    Lipase enzyme from Aspergillus oryzae (EC 3.1.1.3) was immobilized onto a micro porous polymeric matrix which contains aldehyde functional groups and methyl esters of long chain fatty acids (biodiesel) were synthesized by transesterification of crude canola oil using immobilized lipase. Micro porous polymeric matrix was synthesized from styrene-divinylbenzene (STY-DVB) copolymers by using high internal phase emulsion technique and two different lipases, Lipozyme TL-100L ® and Novozym 388 ® , were used for immobilization by both physical adsorption and covalent attachment. Biodiesel production was carried out with semi-continuous operation. Methanol was added into the reactor by three successive additions of 1:4 M equivalent of methanol to avoid enzyme inhibition. The transesterification reaction conditions were as follows: oil/alcohol molar ratio 1:4; temperature 40 o C and total reaction time 6 h. Lipozyme TL-100L ® lipase provided the highest yield of fatty acid methyl esters as 92%. Operational stability was determined with immobilized lipase and it indicated that a small enzyme deactivation occurred after used repeatedly for 10 consecutive batches with each of 24 h. Since the process is yet effective and enzyme does not leak out from the polymer, the method can be proposed for industrial applications. -- Research highlights: → Lipozyme TL-100L and Novozym 388 were immobilized onto micro porous polymeric matrix by both physical adsorption and covalent linking. → Immobilized enzymes were used for synthesis of fatty acid methyl esters by transesterification of canola oil and methanol using semi-continuous operation system. → According to chromatographic analysis, Lipase Lipozyme TL-100L resulted in the highest yield of methyl ester as 92%.

  7. Reversible thermal denaturation of immobilized rhodanese

    International Nuclear Information System (INIS)

    Horowitz, P.; Bowman, S.

    1987-01-01

    For the first time, the enzyme rhodanese had been refolded after thermal denaturation. This was previously not possible because of the strong tendency for the soluble enzyme to aggregate at temperatures above 37 degrees C. The present work used rhodanese that was covalently coupled to a solid support under conditions that were found to preserve enzyme activity. Rhodanese was immobilized using an N-hydroxymalonimidyl derivative of Sepharose containing a 6-carbon spacer. The number of immobilized competent active sites was measured by using [ 35 S]SO 3 (2-) to form an active site persulfide that is the obligatory catalytic intermediate. Soluble enzyme was irreversibly inactivated in 10 min at 52 degrees C. The immobilized enzyme regained at least 30% of its original activity even after boiling for 20 min. The immobilized enzyme had a Km and Vmax that were each approximately 3 times higher than the corresponding values for the native enzyme. After preincubation at high temperatures, progress curves for the immobilized enzyme showed induction periods of up to 5 min before attaining apparently linear steady states. The pH dependence of the activity was the same for both the soluble and the immobilized enzyme. These results indicate significant stabilization of rhodanese after immobilization, and instabilities caused by adventitious solution components are not the sole reasons for irreversibility of thermal denaturation seen with the soluble enzyme. The results are consistent with models for rhodanese that invoke protein association as a major cause of inactivation of the enzyme. Furthermore, the induction period in the progress curves is consistent with studies which show that rhodanese refolding proceeds through intermediate states

  8. Using Gel Electrophoresis To Illustrate Protein Diversity and Isoelectric Point.

    Science.gov (United States)

    Browning, Mark; Vanable, Joseph

    2002-01-01

    Demonstrates the differences in protein structures by focusing on isoelectric point with an experiment that is observable under certain pH levels in gel electrophoresis. Explains the electrophoresis procedure and reports results of the experiments. (YDS)

  9. Construction of mussel-inspired coating via the direct reaction of catechol and polyethyleneimine for efficient heparin immobilization

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yujie [School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); The Institute of Biomaterials and Surface Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Luo, Rifang, E-mail: lrifang@126.com [School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); The Institute of Biomaterials and Surface Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Shen, Fangyu; Tang, Linlin [School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); The Institute of Biomaterials and Surface Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Wang, Jin, E-mail: jinxxwang@263.net [School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); The Institute of Biomaterials and Surface Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Huang, Nan [School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); The Institute of Biomaterials and Surface Engineering, Southwest Jiaotong University, Chengdu 610031 (China)

    2015-02-15

    Highlights: • Catechol (CA) and PEI copolymerization was a mimetic and dopamine-like coating method. • CA/PEI film provided amine groups and was effective in heparin immobilization. • CA/PEI coating could inhibit smooth muscle cell proliferation. • CA/PEI coating did not show any significant cytotoxicity to endothelial cell. - Abstract: Dopamine could self-polymerize to form the coating on various substrates and the co-existence of catechols and amines was crucial in performing such polymerization process. In this work, a mimetic approach of coating formation was carried out based on the co-polymerization of catechol (CA) and polyethyleneimine (PEI). Mussel-inspired CA/PEI coating was deposited on 316L stainless steel (SS). Fourier transform infrared spectra (FTIR) and X-ray photoelectron spectroscopy (XPS) demonstrated the successful coating formation. QCM measurement showed good affinity of heparin immobilization on CA/PEI coating surface ascribed to the amine groups. Herein, vascular cell-material interactions like endothelial cells (ECs) and smooth muscle cells (SMCs) were also investigated. Interestingly, CA/PEI and heparin modified coatings presented no cytotoxicity to ECs, however to a certain extent, decreased SMCs proliferation. Moreover, heparin-binding surface presented significant anti-platelet adhesion and activation properties. These results effectively suggested that the mussel-inspired CA/PEI coating might be promising when served as a platform for biomolecule immobilization.

  10. Large abnormal peak on capillary zone electrophoresis due to contrast agent.

    Science.gov (United States)

    Wheeler, Rachel D; Zhang, Liqun; Sheldon, Joanna

    2017-01-01

    Background Some iodinated radio-contrast media absorb ultraviolet light and can therefore be detected by capillary zone electrophoresis. If seen, these peaks are typically small with 'quantifications' of below 5 g/L. Here, we describe the detection of a large peak on capillary zone electrophoresis that was due to the radio-contrast agent, Omnipaque™. Methods Serum from a patient was analysed by capillary zone electrophoresis, and the IgG, IgA, IgM and total protein concentrations were measured. The serum sample was further analysed by gel electrophoresis and immunofixation. Results Capillary zone electrophoresis results for the serum sample showed a large peak with a concentration high enough to warrant urgent investigation. However, careful interpretation alongside the serum immunoglobulin concentrations and total protein concentration showed that the abnormal peak was a pseudoparaprotein rather than a monoclonal immunoglobulin. This was confirmed by analysis with gel electrophoresis and also serum immunofixation. The patient had had a CT angiogram with the radio-contrast agent Omnipaque™; addition of Omnipaque™ to a normal serum sample gave a peak with comparable mobility to the pseudoparaprotein in the patient's serum. Conclusions Pseudoparaproteins can appear as a large band on capillary zone electrophoresis. This case highlights the importance of a laboratory process that detects significant electrophoretic abnormalities promptly and interprets them in the context of the immunoglobulin concentrations. This should avoid incorrect reporting of pseudoparaproteins which could result in the patient having unnecessary investigations.

  11. Properties of immobilized papain by radiation polymerization

    International Nuclear Information System (INIS)

    Kumakura, Minoru; Kaetsu, Isao

    1984-01-01

    Papain was immobilized by the radiation polymerization of various monomers at low temperatures and the effects of the polymer matrix on the enzyme activity and thermal stability of the immobilized enzymes were studied. The activity of the immobilized enzymes prepared from monofunctional (acrylate and methacrylate) monomers was higher than that from bifunctional (bismethacrylate) monomers and that from polyoxyethylene dimethacrylate monomers increased with an increase in the number of oxyethylene units. The thermal stability of the immobilized enzymes prepared from hydrophilic monomers was higher than that from hydrophobic monomers and increased markedly with increasing monomer concentration. (author)

  12. Assessment of DNA damage and Chromosome aberration in human lymphocyte exposed to low dose radiation detected by FISH(Fluorescence In Situ Hybridization) and SCGE(Single Cell Gel Electrophoresis)

    International Nuclear Information System (INIS)

    Chung, Hai Won; Kim, Su Young; Kim, Byung Mo; Kim, Sun Jin; Ha, Sung Whan; Kim, Tae Hwan; Cho, Chul Koo

    2000-01-01

    Comparative study was performed for the assessment of DNA damage and Chromosomal aberration in human lymphocyte exposed to low dose radiation using Fluorescence In Situ Hybridization(FISH) and Single Cell Gel Electrophoresis(SCGE). Chromosomal aberrations in human lymphocyte exposed to radiation at doses of 5, 10, 30 and 50cGy were analysed with whole chromosome-specific probes by human chromosome 1, 2 and 4 according to PAINT system. FISH with chromosome-specific probe has been used to be a valid and rapid method for detection of chromosome rearrangements induced by low dose radiation. The frequencies of stable translocation per cell equivalents were 0.0116, 0.0375, 0.0407, 0.0727 and 0.0814 for 0, 5, 10, 30 and 50cGy, respectively, and those of dicentric were 0.00, 0.0125, 0.174, 0.0291 and 0.0407 respectively. Radiation induced DNA damage in human lymphocyte in a dose-dependent manner at low doses from 5cGy to 50cGy, which were analysed by single Cell Gel Electrophoresis(SCGE). From above results, FISH seemed to be useful for radiation biodosimetry by which the frequencies of stable aberrations in human lymphocyte can be observed more easily than by conventional method and SCGE also seemed to be sensitive method for detecting DNA damage by low dose radiation exposure, so that those methods will improve our technique to perform meaningful biodosimetry for radiation at low doses

  13. Quantitative analysis by microchip capillary electrophoresis – current limitations and problem-solving strategies

    NARCIS (Netherlands)

    Revermann, T.; Götz, S.; Künnemeyer, Jens; Karst, U.

    2008-01-01

    Obstacles and possible solutions for the application of microchip capillary electrophoresis in quantitative analysis are described and critically discussed. Differences between the phenomena occurring during conventional capillary electrophoresis and microchip-based capillary electrophoresis are

  14. Establishment of the optimum two-dimensional electrophoresis system of ovine ovarian tissue.

    Science.gov (United States)

    Jia, J L; Zhang, L P; Wu, J P; Wang, J; Ding, Q

    2014-08-26

    Lambing performance of sheep is the most important economic trait and is regarded as a critic factoring affecting the productivity in sheep industry. Ovary plays the most roles in lambing trait. To establish the optimum two-dimensional electrophoresis system (2-DE) of ovine ovarian tissue, the common protein extraction methods of animal tissue (trichloroacetic acid/acetone precipitation and direct schizolysis methods) were used to extract ovine ovarian protein, and 17-cm nonlinear immobilized PH 3-10 gradient strips were used for 2-DE. The sample handling, loading quantity of the protein sample, and isoelectric focusing (IEF) steps were manipulated and optimized in this study. The results indicate that the direct schizolysis III method, a 200-μg loading quantity of the protein sample, and IEF steps II (20°C active hydration, 14 h→500 V, 1 h→1000 V 1 h→1000-9000 V, 6 h→80,000 VH→500 V 24 h) are optimal for 2-DE analysis of ovine ovarian tissue. Therefore, ovine ovarian tissue proteomics 2-DE was preliminarily established by the optimized conditions in this study; meanwhile, the conditions identified herein could provide a reference for ovarian sample preparation and 2-DE using tissues from other animals.

  15. Inexpensive and Safe DNA Gel Electrophoresis Using Household Materials

    Science.gov (United States)

    Ens, S.; Olson, A. B.; Dudley, C.; Ross, N. D., III; Siddiqi, A. A.; Umoh, K. M.; Schneegurt, M. A.

    2012-01-01

    Gel electrophoresis is the single most important molecular biology technique and it is central to life sciences research, but it is often too expensive for the secondary science classroom or homeschoolers. A simple safe low-cost procedure is described here that uses household materials to construct and run DNA gel electrophoresis. Plastic…

  16. Preparation of Laccase Immobilized Cryogels and Usage for Decolorization

    Directory of Open Access Journals (Sweden)

    Murat Uygun

    2013-01-01

    Full Text Available Poly(methyl methacrylate-co-glycidyl methacrylate (poly(MMA-co-GMA cryogels were synthesized by radical cryopolymerization technique. Then, laccase enzyme was covalently attached to the cryogel and characterized by using swelling studies and SEM and EDX analyses. Kinetic properties and optimum conditions of the immobilized and free laccase were studied and it was found that of the immobilized laccase was lower than that of free laccase. of the immobilized laccase was increased upon immobilization. Optimum pH was found to be 4.0 for each type of laccase, while optimum temperature was shifted to the warmer region after the immobilization. It was also found that thermal stability of the immobilized laccase was higher than that of free laccase. Immobilized laccase could be used for 10 times successive reuse with no significant decrease in its activity. Also, these laccase immobilized cryogels were successfully used for the decolorization of seven different dyes.

  17. Dynamic computer simulations of electrophoresis: three decades of active research.

    Science.gov (United States)

    Thormann, Wolfgang; Caslavska, Jitka; Breadmore, Michael C; Mosher, Richard A

    2009-06-01

    Dynamic models for electrophoresis are based upon model equations derived from the transport concepts in solution together with user-inputted conditions. They are able to predict theoretically the movement of ions and are as such the most versatile tool to explore the fundamentals of electrokinetic separations. Since its inception three decades ago, the state of dynamic computer simulation software and its use has progressed significantly and Electrophoresis played a pivotal role in that endeavor as a large proportion of the fundamental and application papers were published in this periodical. Software is available that simulates all basic electrophoretic systems, including moving boundary electrophoresis, zone electrophoresis, ITP, IEF and EKC, and their combinations under almost exactly the same conditions used in the laboratory. This has been employed to show the detailed mechanisms of many of the fundamental phenomena that occur in electrophoretic separations. Dynamic electrophoretic simulations are relevant for separations on any scale and instrumental format, including free-fluid preparative, gel, capillary and chip electrophoresis. This review includes a historical overview, a survey of current simulators, simulation examples and a discussion of the applications and achievements of dynamic simulation.

  18. Interaction of albumins and heparinoids investigated by affinity capillary electrophoresis and free flow electrophoresis.

    Science.gov (United States)

    Mozafari, Mona; El Deeb, Sami; Krull, Friederike; Wildgruber, Robert; Weber, Gerhard; Reiter, Christian G; Wätzig, Hermann

    2018-02-01

    A fast and precise affinity capillary electrophoresis (ACE) method has been applied to investigate the interactions between two serum albumins (HSA and BSA) and heparinoids. Furthermore, different free flow electrophoresis methods were developed to separate the species which appears owing to interaction of albumins with pentosan polysulfate sodium (PPS) under different experimental conditions. For ACE experiments, the normalized mobility ratios (∆R/R f ), which provided information about the binding strength and the overall charge of the protein-ligand complex, were used to evaluate the binding affinities. ACE experiments were performed at two different temperatures (23 and 37°C). Both BSA and HSA interact more strongly with PPS than with unfractionated and low molecular weight heparins. For PPS, the interactions can already be observed at low mg/L concentrations (3 mg/L), and saturation is already obtained at approximately 20 mg/L. Unfractionated heparin showed almost no interactions with BSA at 23°C, but weak interactions at 37°C at higher heparin concentrations. The additional signals also appeared at higher concentrations at 37°C. Nevertheless, in most cases the binding data were similar at both temperatures. Furthermore, HSA showed a characteristic splitting in two peaks especially after interacting with PPS, which is probably attributable to the formation of two species or conformational change of HSA after interacting with PPS. The free flow electrophoresis methods have confirmed and completed the ACE experiments. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Physicochemical and biochemical interactions in yeast immobilization by adhesion to a cellulose based support

    OpenAIRE

    Kurec, M.; Brányik, Tomáš; Mota, André; Domingues, Lucília; Teixeira, J. A.

    2008-01-01

    An important quality of yeast cell wall is the ability to adhere to other cell walls or solid surfaces. This feature of yeast is responsible for technologically important phenomena such as flocculation at the end of beer fermentation and cell adhesion to immobilization supports e.g. spent grains, DEAE-cellulose etc. Physicochemical properties of yeast surfaces, e.g. hydrophobicity and surface charge, have a substantial impact on cell adhesion and flocculation. The interaction e...

  20. Continuous Production of Isomalto-oligosaccharides by Thermo-inactivated Cells of Aspergillus niger J2 with Coarse Perlite as an Immobilizing Material.

    Science.gov (United States)

    Huang, Zhihua; Li, Zhihong; Su, Yongjian; Zhu, Yongfeng; Zeng, Wei; Chen, Guiguang; Liang, Zhiqun

    2018-02-13

    The coarse perlite 40-80 mesh was selected as an immobilizing material and put into a packed bed reactor (PBR) to continuously convert maltose to isomalto-oligosaccharides (IMOs). The PBR was prepared by mixing the thermo-inactivated cells (TIC) from Aspergillus niger J2 strain with the coarse perlite, then the mixture was put into an overpressure-resistant column. Compared with diatomite 40-80 mesh and thin perlite 80-120 mesh in PBR, coarse perlite was chosen as the best filtration aid, when the ratio of coarse perlite versus TIC was 1:1. The thermal and pH stability of the free and immobilized TIC and the optimum conditions for the transglycosylation reactions were determined. The results show that approximately 75 and 82% and 87 and 91% of α-glucosidase activity were reserved for free and immobilized TIC at temperatures from 30 to 60 °C and pH from 3.00 to 7.00 for 12 h, respectively. With 30% malt syrup under the conditions of 50 °C and pH 4.00, a mini-scale packed bed reactor (Mi-PBR) and medium-scale packed bed reactor (Me-PBR) could continuously produce IMO over 25 and 34 days with the yield of effective IMO (eIMO) ≥ 35% and total IMO (tIMO) ≥ 50%, respectively. The strategy of mixing the coarse perlite with TIC in PBR is a novel approach to continuously produce IMO and has great application potential in industry.