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Chapatwala K D - - 1998
Pseudomonas putida utilizes cyanide as the sole source of carbon and nitrogen. Agar, alginate, and carrageenan were screened as the encapsulating matrices for P. putida. Alginate-immobilized cells of P. putida degraded sodium cyanide (NaCN) more efficiently than non-immobilized cells or cells immobilized in agar or carrageenan. The end products of ...
Ayala A - - 1998
The Rotofor cell is a preparative isoelectric focusing (IEF) apparatus, in which IEF is performed entirely in free solution. Electrofocusing in Rotofor cell has been described as well-suited for use at any stage of a purification scheme. However, it has some important limitations in resolving complex mixtures of proteins. This ...
Darah I - - 1998
The production of lignin-degrading enzymes by free and entrapped cells ofPhanerochoete chrysosporium in a tubular air-lift bioreactor was studied. Under optimized cultural conditions the production of lignin peroxidase by free cells, calcium-alginate-entrapped cells and scouring-mesh-entrapped cells was in a ratio of 520ratio720ratio950 mU/mL, while the production of manganese peroxidase was ...
Zhang Y - - 1998
A new cell immobilization method was developed in which cells of Arthrobacter simplex BY-2-3-51 were immobilized by entrapment with a polyvinyl alcohol-alginate complex carrier. The immobilized cells preparation contains spherical beads with high mechanical strength and delta 1-dehydrogenase activity. The activation conditions and enzymatic properties of the immobilized cells were ...
Nawaz M S - - 1998
The influences of concentration of acrylamide, pH, temperature, duration of storage of encapsulated cells and presence of different metals and chelators on the ability of immobilized cells of a Rhodococcus sp. to degrade acrylamide were evaluated. Immobilized cells (3 g) rapidly degraded 64 and 128 mM acrylamide in 3 and ...
Nakamura T - - 1997
Human skin fibroblasts were cultured in the presence of 0.5 mM 4-methylumbelliferone for 12 h, and cell-free synthesis of hyaluronic acid was performed using membrane-rich fraction from the cells. The preincubation of the cells with 4-methylumbelliferone reduced hyaluronic acid synthesis to 15% of that of non-preincubated cells, although its chain ...
Lee T H - - 1997
An efficient sporulation/immobilization procedure for immobilized fungal cell culture was developed by modifying an existing immobilized technique to shorten the time and number of steps for sporulation. This method was applied to an immobilized-cell perfusion bioprocess (IPB) for continuous production of CyA, an intracellular secondary metabolite produced by a filamentous ...
Akashi T - - 1997
Purple-coloured dandelion (Taraxacum officinale) callus cultures producing anthocyanin pigments were established on a cytokinin-rich medium under the light. When the cells were placed in the dark, only grey cells proliferated. Anthocyanin productivity of these cells was partially restored in the light. The major pigment was identified as cyanidin 3-(6"-malonylglucoside). The ...
Seifert D B - - 1997
A novel gel entrapment method has been developed where macropores are created within alginate beads to provide an environment for high-density growth of mammalian cells. The method takes advantage of an interaction between poly(ethylene glycol) (PEG) and alginate to provide a network of pores within the bead for growth while ...
Leenen E J - - 1997
The dynamics of growth and death of immobilized Nitrosomonas europaea were studied. For this, the death rate of suspended cells was determined in the absence of ammonium or oxygen by following the loss of respiration activity and by fluorescein-diacetate (FDA)/lissamine-green staining techniques. The death rates obtained (1.06 x 10(-6) s(-1) ...
Tripathi C K - - 1997
Production of L-phenylacetylcarbinol (L-PAC) through biotransformation of benzaldehyde by free and immobilized cells of the yeast Saccharomyces cerevisiae has been attempted. L-PAC production was found to be maximum (0.4 microliter/ml) when anaerobically grown free cells were used as biocatalyst during aerobic biotransformation for two hours with magnetically stirred bioreactor. Growth ...
Ho K L - - 1997
Plastic composite supports containing 50% agricultural products (oat hulls, soybean hulls, yeast extract, soybean flour, dried bovine erythrocytes, bovine albumin, and/or mineral salts) and 50% (wt/wt) polypropylene were produced by high-temperature twin-screw extrusion. The research employed two half sets of a five-factorial fractional design (2(5 - 1)) to evaluate the ...
Jirků V - - 1997
Covalent attachment of Candida utilis cells, possibly simulating natural microbial immobilizations, stimulated stable and significant enhancement of extracellular production of alkaline protease, specifically induced by four different starvation conditions. The enzyme analysis confirmed the identity of the proteases released under all conditions of starvation and no parallel production of other ...
Savinova O - - 1997
The combination of vertical, one-dimensional isoelectric focusing and immunoblotting works very well for the evaluation of the phosphorylation state of the alpha-subunit of eIF2 using reticulocyte lysate or purified eIF2. However, the method is more difficult to apply to the analysis of eIF2 alpha phosphorylation in cultured cells. In part ...
Schenzle A - - 1997
Ralstonia eutropha JMP 134 utilizes 3-nitrophenol as the sole source of nitrogen, carbon, and energy. The entire catabolic pathway of 3-nitrophenol is chromosomally encoded. An initial NADPH-dependent reduction of 3-nitrophenol was found in cell extracts of strain JMP 134. By use of a partially purified 3-nitrophenol nitroreductase from 3-nitrophenol-grown cells, ...
Sodini I - - 1997
Four strains of mesophilic lactic acid bacteria were separately or coentrapped in kappa-carrageenan/locust bean gum gel beads and used for continuous prefermentation of UHT skim milk in a stirred-tank bioreactor. Lactic acid and cell productivities of the immobilized cell bioreactor were particularly high and remarkably stable during eight weeks of ...
Bay B H - - 1997
Vanadium has recently been reported to induce interphase and M-phase (mitotic) programmed cell death via the generation of hydroxyl free radicals (OH*). In this paper, the effects of antioxidants on: (a) vanadyl[IV]-generated OH* free radical levels; and (b) cellular glutathione in vanadyl [IV]-treated Chang liver cells were evaluated. The surface ...
Huang Y L - - 1997
Continuous production of a recombinant murine granulocyte-macrophage colony-stimulating factor (GM-CSF) by Saccharomyces cerevisiae strain XV2181 (a/a, Trp 1) containing plasmid palphaADH2 and immobilized on porous glass beads in a fluidized bed bioreactor was studied. Kinetic models for plasmid stability, cell growth, and protein production in the three-phase fluidized bed bioreactor ...
Ogata Y - - 1997
In this paper, we used the extracts from cementum, bone, dentin and enamel, and compared the chemotactic behavior of human periodontal ligament (HPDL) cells, human gingival fibroblasts (HGF) and human alveolar bone (HAB) cells using modified Boyden chambers. The extracts, obtained using 4 M guanidine HCl ("G" extract), from cementum, ...
Ito Y - - 1997
Insulin was immobilized on prescribed areas of poly(ethylene terephthalate) film by photolithography. Chinese hamster ovary cells overexpressing human insulin receptors were cultured on the pattern-immobilized film. Pattern-immobilized insulin did not enhance cell adhesion but transduced a signal to the cells through phosphorylation of tyrosine residues of signal proteins. In addition, ...
Hasséus B - - 1997
Smokeless tobacco (ST) is known to adversely effect the oral mucosa, but knowledge about the influence on immune defence is limited. Few studies have investigated the effect of ST on the local immune response. In the present study, we have assessed the effect of a crude Swedish moist snuff (SS) ...
Lancaster J R JR - - 1997
In this review, I consider the quantitative consequences of the diffusion of free NO in determining its biological actions. Several studies have measured the extent to which NO diffuses away from an NO-producing cell, and the distance of its diffusion is quite large, on the order of 100-200 microm. This ...
Rangel M - - 1997
The few reports about diatom toxins are related to central nervous system toxicity, induced by domoic acid. In the present work Nitzschia sp. (Bacillariophyceae) was studied. The cells were cultured in f/2 medium, under 4000 lux and 14/10 hr light/dark cycle. After massive growth (5 x 10(6) cells/ml) the diatom ...
Seki M - - 1997
The production characteristics for Taxol (paclitaxel) using free and immobilized cells of Taxus cuspidata were investigated in a perfusion culture bioreactor. Although the cell growth was inhibited by higher dilution rates, the specific production rate of Taxol was increased by perfusion compared with that using batch operation. Perfusion cultures using ...
Worthington A E - - 1997
Intense ultrasound beams may have the potential to treat malignant tumours when combined with sensitizers, often called sonodynamic agents. Some of these agents, e.g., the porphyrins, are currently used for photodynamic therapy. However, the experimental evidence for ultrasound activation of sensitizers is inconsistent. This paper attempts to discover whether they ...
Wolska-Mitaszko B - - 1997
Trehalase (THA) activity from S. cerevisiae spores and vegetative cells could be differentiated in cell-free extracts. THA from the vegetative cells has an optimal activity at neutral pH whereas biphase pH optimum in the spores was observed. The enzyme from the spores exhibited higher thermostability than that from the vegetative ...
Parra L - - 1996
Mesophyllic lactobacilli cultures propagated in MRS broth were inoculated in goats' milk curd slurries and incubated at 30 degrees C for 10 d. The micro-organisms tested were Lactobacillus casei subsp. casei IFPL 731 and IFPL 99, and Lactobacillus plantarum IFPL 3. Whole cells, cell-free extracts and cell lysates were evaluated ...
He Z - - 1996
Nucleotide excision repair (NER) is the primary mechanism by which both Saccharomyces cerevisiae and human cells remove the DNA lesions caused by ultraviolet light and other mutagens. This complex process involves the coordinated actions of more than 20 polypeptides. To facilitate biochemical studies of NER in yeast, we have established ...
Härtel U - - 1996
Growing cells of Acidaminococcus fermentans (DSM 20731 and ATCC 25085) fermented trans-aconitate via citrate, oxaloacetate, and pyruvate to approximately 2 CO2, 1.8 acetate, 0.1 butyrate and 0.9 H2. The carbon and electron recoveries were close to 100%. On citrate no growth was observed and washed cells were unable to ferment ...
Mendz G L - - 1996
The presence and activities of the enzymes of the urea cycle in the bacterium Helicobacter pylori were investigated employing one- and two-dimensional NMR spectroscopy and radioactive tracer analysis. Cell suspensions, lysates and membrane preparations generated L-ornithine and ammonium at high rates in incubations with L-arginine, indicating the presence of arginase ...
Inanç E - - 1996
The effect of reduced oxygen supply on the production of a recombinant protein (plasmid-encoded beta-galactosidase) was investigated in Escherichia coli. A novel modified bubble tank reactor was used to provide a direct comparison between immobilized and suspended cells in identical environments except for the immobilization matrix. Decreased oxygen supply led ...
Wilson A L - - 1996
Previous studies have reached differing conclusions as to whether or not guanine-nucleotide-dependent conformational changes affect the ability of Rab proteins to undergo post-translational modification by Rab:geranylgeranyltransferase (Rab-GGTase). We now show that the ability of a Rab1B mutant [Q67L (Gln-67-->Leu)] with reduced intrinsic GTPase activity to undergo geranylgeranylation in cell-free assays ...
Szajáni B - - 1996
Saccharomyces cerevisiae cells were immobilized on preformed cellulose beads by adsorption. The fermentation capacity of the immobilized yeast cells was found to be practically independent of the hydrogen ion concentration between pH 3.1 and 6.25. The fermentation capacity was maximal at 30 degrees C. The immobilized yeast cells were used ...
Ferreira G M - - 1996
Electrophoretic and kinetic determinations of the activity of lactate dehydrogenase in murine erythroleukaemic (MEL) cells, sampled at 1 min intervals, reveal distinct oscillations in the activity and amount of active isozyme. Both oscillations have periods in the range of 2-6 min (probably less) and both appear to be rhythmically modulated ...
Michaels J D - - 1996
It has been established that the forces resulting from bubbles rupturing at the free air (gas)/liquid surface injure animal cells in agitated and/or sparged bioreactors. Although it has been suggested that bubble coalescence and breakup within agitated and sparged bioreactors (i.e., away from the free liquid surface) can be a ...
Mesland D A - - 1996
A device is described in which a biological specimen is periodically accelerated for a short period. Each event is followed by a variable period of free fall. Assuming that the g-dose (expressed g s) has to surpass a certain minimal value to be perceived by cells, and in addition, there ...
Shu C H - - 1996
Continuous production of a recombinant murine granulocyte-macrophage colony-stimulating factor (MuGM-CSF) by immobilized yeast cells, Saccharomyces cerevisiae strain XV2181 (a/a, Trp1) containing plasmid palphaADH2, in a fluidized bed bioreactor was studied at a 0.03 h(-1) dilution rate and various particle loading rates ranging from 5% to 33% (v/v). Cells were immobilized ...
Chang H N - - 1996
As a means of integrating cell growth and immobilization, recombinant Saccharomyces cerevisiae cells with invertase activity were immobilized in liquid-core alginate capsules and cultured to a high density. S. cerevisiae cells of SEY 2102 (MAT alpha ura3-52 leu2-3, 112 his4-519) harboring plasmid pRB58 with the SUC2 gene coding for invertase ...
Yang S T - - 1996
The continuous production of murine granulocyte-macrophage colony-stimulating factor (GM-CSF) by recombinant yeast cells immobilized in a fibrous-bed bioreactor was studied. A high cell density of approximately 68 g/L and a GM-CSF productivity of approximately 3.5 mg/L.h were attained in the fibrous-bed bioreactor-fed with a rich (nonselective, pH 6.7) medium at ...
Li X - - 1996
A method was developed for increasing the stability of calcium alginate beads with entrapped Saccharomyces cerevisiae cells. Polyelectrolyte complexes were used as surface-coating materials by dropping alginate into chitosan. The coacervation agent sodium triphosphate was needed for the formation of the polyelectrolyte complexes. Gel beads maintained their rigidity during ethanol ...
Henke J - - 1996
As the cell membranes are one of the targets of drug treatment in cancer cells, their membrane composition and variations in this composition need to be analyzed. Gradient selected 2D-NMR inverse heteronuclear chemical shift correlations are have described, which offer optimum sensitivity combined with a high reliability for unequivocal signal ...
Klein R - - 1996
Intracellular dictyopterin, which is present in reduced form, mainly as tetrahydrodictyopterin, both in vegetative cells and in starved cells, could neither be detected in dormant spores nor in unswollen or swollen activated spores. Synthesis of tetrahydrodictyopterin starts with emergence of nascent amoebae during spore germination. Tetrahydrodictyopterin levels in cell-free extracts ...
Huppe H. C. - - 1996
Extractable glucose-6-phosphate dehydrogenase activity is higher from N-limited Chlamydomonas reinhardtii cells than from N-sufficient cells. Native gels reveal that the isoform complexity varies depending on the form of N supplied. The isoforms associated with NO3- growth appear within 2 h of switching cells from NH4+ to NO3-.
Farcasanu I C - - 1996
The fate of Mn2+ inside Saccharomyces cerevisiae cells was monitored during import and export processes, using information from electron paramagnetic resonance (EPR) spectroscopy analysis. EPR spectra showed that when entering the cell in high number, manganese ions immediately precipitated. If recorded under conditions that favored manganese efflux, EPR spectra indicated ...
Babu G R - - 1996
Our isolate, Pseudomonas putida, is known to be capable of utilizing cyanides as the sole source of carbon (C) and nitrogen (N) both in the form of free cells and cells immobilized in calcium alginate. In the present study, the cell-free extract(s) were prepared from the cells of P. putida ...
Scheid C - - 1996
Oxalate, the most common constituent of kidney stones, is an end product of metabolism that is excreted by the kidney. During excretion, oxalate is transported by a variety of transport systems and accumulates in renal tubular cells. This process has been considered benign; however, recent studies on LLC-PK1 cells suggested ...
Parascandola P - - 1996
Yeast cells immobilized by entrapment in an insolubilized gelatin gel have been investigated with regard to their pattern of growth and respiratory activity. 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 ...
Xu X - - 1996
An artificial biofilm system consisting of Pseudomonas aeruginosa entrapped in alginate and agarose beads was used to demonstrate transport limitation of the rate of disinfection of entrapped bacteria by chlorine. Alginate gel beads with or without entrapped bacteria consumed chlorine. The specific rate of chlorine consumption increased with increasing cell ...
Chen Z - - 1996
Based on the initial optimization of DMEM:F12(1:1), two kinds of serum-free media, 11G-SG-SFM and 11G-SE-SFM, were formulated by using orthogonal experiments for the growth of genetically engineered CHO cell line 11G and the production of recombinant prourokinase (pro-UK) in a suspension culture, respectively. Growth of 11G cells in 11G-SG-SFM was ...
Ciani M - - 1996
Screening tests carried out for 10 strains of Candida stellata confirmed high levels of glycerol production, although a low fermentation rate and reduced ethanol content were observed. To overcome the poor competition with Saccharomyces cerevisiae, fermentation tests with immobilized C. stellata cells, alone or in combination with S. cerevisiae, have ...
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