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1

Release of Pr3plus ions from liposomes affected by single and double-chain ammonium chlorides

100%
Gabrielska J., Pawlowicz P., Sarapuk J.
Polish Journal of Environmental Studies
|
1992
|
tom 01
|
nr 2
By using the lH—NMR method and paramagnetic ions Pr3+, the incorporation into the liposome membrane of a series of biologically active single-chain (TGE-n) and double-chain (DGE-n) quaternary ammonium salts was studied. Corresponding compounds of both groups differed in their alkyl chain-length (n = 8,10,12,14 and 16). Minimal concentration CA of compounds TGE-n and DGE-n which caused total release of Pr3+ ions from the external layer of liposome membrane and the ratio of CA to the 4.5 mM extravesicular concentration of Pr3+ (CPr) used in experiments was determined. Based on the results obtained, one can conclude that the effectiveness of Pr3+ release from liposome membrane is (with n = 12,14 and 16) twice as high for double-chain compounds as for analogous single-chain compounds, and about 2.5 and 5 times higher for DGE-10 and DGE-8 than for TGE-10 and TGE-8, respectively.
2

Synthesis of a quaternary polyprenyl ammonium salt

88%
Sizova O. V., Utkina N. S., Kalinchuk N. A., Danilov L. L., Maltsev S. D.
Acta Biochimica Polonica
|
2007
|
tom 54
|
nr 4
869-872
Reaction of primary C55-allylic alcohol moraprenol (WT3C7-9-OH, a polyprenol from mulberry leaves) with triethylamine in the presence of phosphorus oxychloride leads to a quaternary ammonium chloride with a good yield (72%) and high cis-stereoselectivity of the terminal isoprene unit. Cationic polyprenyl derivatives may be useful for transfection and immunological studies
3

Gemini alkylammonium salts as biodeterioration inhibitors

88%
Brycki B.
Polish Journal of Microbiology
|
2010
|
tom 59
|
nr 4
To protect materials against biodetenoration, physical, biological or chemical methods can be used. Chemical inhibitors of biodetenoration are the most common and effective. A new class of chemical inhibitors-gemini alkylammonium salts-shows excellent biocidal properties and good ecological profile. These compounds can be applied as biodeterioration inhibitors in a wide variety of materials.
4
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Effect of aminoacids on the fungicidal activity of quaternary ammonium salts

88%
Piatkowski J., Swiatek M.
Acta Mycologica
|
2010
|
tom 45
|
nr 2
Amphipatic compounds exhibit an antimicrobial action both on bacteria and fungi. It is caused by a penetrative property of hydrophobic carbon chain of the compuound into a plasma membrane as well as by additional interaction of membrane elements and a hydrophilic amphipathic compound head. Bactericidal and fungicidal activity of this compound strongly depends on chemical environmental factors. In general, microorganisms are not as sensitive in a full medium as in a minimal one and the level of sensitivity rises when the amphipatic compounds are presend in destilled water. Similarly, the sensitivity is stronger in fluid than on solid medium. Our researches revealed however that some aminoacids, although they are complex organic compounds, increase the microbial sensitivity to some tested compound. This efect depends on a microorganism and on a kind of compound. The highest hipersensitivity has been observed against yeast-like fungi when arginine was a cooperating aminoacid. The effect concerns Trichosporon but not E.coli, not occurs in relation to SDS, quaternary ammonium salt IA, and bisammonium salts. Certainly the effect exhibit QAS, which have simple composition of hydrophilic „head” consisting only of methyl group, attaching to alkilic chain possessing keton group, build of 14 or 16 carbon atoms.
5

Biological evaluation of quaternary bis ammonium salt and cetylpyridinum bromide against S. epidermidis biofilm

75%
Stefanska J., Pietruczuk-Padzik A., Struga M., Borkowski M., Tyski S.
Polish Journal of Microbiology
|
2013
|
tom 62
|
nr 4
Quaternary ammonium compounds are broad-spectrum bacteriocides widely used as antiseptics, disinfection and preservation agents. The aim of this study was to examine the activity of two quaternary ammonium salts, cetylpyridinum bromide and a newly synthesized quaternary bis ammonium salt, against S. epidermidis biofilm. The average values of killing efficiency for cetylpyridinum bromide ranged from 26.6% to 64.1% for all tested concentrations (0.125 to 8.0 μg×mL⁻¹) and for quaternary bis ammonium salt the percentage of killing efficiency ranged from 59.7% to 88.4% for tested concentrations (from 2.0 to 128.0 μg×mL⁻¹). Both tested compounds significantly affect staphylococcal biofilms, but any of used concentrations caused a total eradication of bacterial biofilm.
6

Effect of 3-pyridylketoxime and its quaternary pyridinium salts on maize germination

75%
Parus A., Wojciechowska A., Szulc P.
Polish Journal of Natural Sciences
|
2017
|
tom 32
|
nr 3
In the present work the impact of the 3-pyridyl ketoxime and its quaternary pyridinium bromides with various alkyl chain lengths on the monocot plant – maize (Zea mays L.) was tested. The study was carried out on two systems – hydroponic and soil. After a seven-day period of these experiments, the number of germinated seeds was counted and the length of maize radicle and shoot was also measured. 3-pyridyl ketoxime and pyridinium ketoxime bromides had varying effects on the germination of maize seeds and the development of radicle and shoot. Toxicity of these compounds depended largely on the structure of the compound, and the systems on which the plant was grown. The toxic effects of tested compounds on maize development were higher in hydroponic systems compared with the soil system.
7

The effect of amphiphilic biocydes contained in a medium on liposome membrane fluidity

75%
Podolak M., Waga S., Przestalski S.
Polish Journal of Environmental Studies
|
1994
|
tom 03
|
nr 2
It was found that quaternary ammonium salt derivatives of glycine ester (GE) admixtures induced increased fluidity of egg yolk lecithin (EYL) liposome membranes (L). The increase depended on chain-lengths of the GEs added and on their concentrations. A maximum fluidity was observed with the 12-carbon atom compound. From considerations concerning the electrostatic interactions in the hydrophilic layer of the liposome mebranes it follows that GEs at low concentrations can induce an increase of binding energy of the layer, while at hihger concentrations the opposite effect can occur.
8

Electric interactions at the lipid membrane surface

63%
Podolak M., Man D.
Cellular and Molecular Biology Letters
|
2002
|
tom 07
|
nr 4
This work presents the results of an experimental study and of computer simulations concerning electric interactions in the surface layer of egg yolk lecithin (EYL) liposome membranes. The surface layer is formed by EYL polar heads, which possess features of electric dipoles, and positive charged polar heads belonging to admixtures of quaternary ammonium salts (AS). The results of the experimental study are in good agreement with the ones of the computer simulations. It was found that fluidity of the membranes, at a given concentration of AS, obtains the extremal (minimal) value. Similarly, the binding energy of the dipoles-positive charges system behaves like that in computer simulations. Moreover, the locations of the fluidity extremum and those of the binding energy depend on the charge of the AS polar heads as well as on the degree of electric interactions screening by the environment. At a certain optimal value of the screening coefficient, the energy of the system is the lowest (the most negative) and together with the rise in AS charge, the minimum of the energy moves towards its higher concentrations.
9

Lysosomotropic N,N- dimethyl alpha-aminoacid n-alkyl esters and their quaternary ammonium salts as plasma membrane and mitochondrial ATPases inhibitors

63%
Oblak E., Lachowicz T. M., Luczynski J., Witek S.
Cellular and Molecular Biology Letters
|
2002
|
tom 07
|
nr 4
A set of n-alkyl esters of N,N-dimethylglycine (DMG-n) and their methobromides (DMGM-n) was synthesized, and their activities on yeast Saccharomyces cerevisiae were compared. The compounds differ in the number of carbon atoms in the aliphatic chain. Aminoesters with 12 carbon atoms appeared to be most active. Unlike quaternary ammonium salts previously tested, the activities of the compounds were not pH-dependent; the minimal inhibitory concentrations (MIC) were identical at pH 8 and at pH 6. In contrast to quaternary ammonium salts, aminoesters showed similar effects on respiratory sufficient (rho+) and respiratory deficient (rho°) mutants. When tested on glucose stimulated proton extrusion, aminoesters applied at MIC increased external pH. Aminoesters inhibited the plasma membrane H+-ATPase, whereas they were less inhibitory on the mitochondrial ATPase. In order to further compare the aminoesters and their corresponding quaternary ammonium salts, derivatives of N,N-dimethylalanine (DMAL-n and DMALM-n, respectively) were synthesized. The quaternary ammonium salts appeared to have a higher inhibitory potency than aminoesters, especially at pH 8, and alanine derivatives inhibited growth at a lower concentration than glycine derivatives. Both alanine derivatives of the aminoester and the quaternary ammonium salt inhibited the plasma membrane H+- ATPase at lower concentrations than glycine derivatives, but the alanine aminoester was without a detectable effect on the mitochondrial ATPase.
10

The physiological and morphological phenotype of a yeast mutant resistant to the quaternary ammonium salt N-[dodecyloxycarboxymethyl]-N,N,N-trimethyl ammonium chloride

63%
Oblak E., Gamian A., Adamski R., Ulaszewski S.
Cellular and Molecular Biology Letters
|
2010
|
tom 15
|
nr 2
We investigated the action of the quaternary ammonium salt (QAS) called IM (N-(dodecyloxycarboxymethyl)-N,N,N-trimethyl ammonium chloride) on Saccharomyces cerevisiae yeast cells. Changes in the yeast cell ultrastructure were confirmed by electron microscopy. We treated resistant mutant cells with QAS, and confirmed destruction of the mutant cytoplasm, an increase in the thickness of the cell wall, separation of the cell wall from the cytoplasm, and the accumulation of numerous lipid droplets. We also observed a relatively high production of lipids in the cells of the parental wild-type strain Σ1278b and in its IM-resistant (IMR) mutant in the presence of the QAS. The IMR mutant showed increased sensitivity to CaCl2 and SDS, and resistance to ethidium bromide, chloramphenicol, erythromycin and osmotic shock. It also tolerated growth at low pH. We suggest that the resistance to IM could be connected with the level of permeability of the cell membrane because the IMR mutant was sensitive to this compound in vivo in the presence of SDS and guanidine hydrochloride, which cause increased permeability of the cell plasma membrane.
11

Application of sonolysis in the process of determination of quaternary ammonium salts in wood

63%
Zabielska-Matejuk J.
Folia Forestalia Polonica. Series B - Drzewnictwo
|
2002
|
tom 33
12

Molecular mechanisms of interaction between amphiphilic ammonium salts and membranes

63%
Przestalski S., Kuczera J.
Polish Journal of Environmental Studies
|
1992
|
tom 01
|
nr 2
This paper is a review of studies on the interaction between cationic, amphiphilic quaternary ammonium salts and biological and model membranes. It has been pointed out that the compounds studied induce changes in both passive and active membrane properties such as mechanical, transport liquid-crystalline and electrical . An attempt has been made to explain the observed effects on the basis of the molecular shape and hydrophobic matching concepts. Some practical implications of the observations and their interpretation have also been noted.
13

A quaternary ammonium salt as an inhibitor of plasma membrane Hplus-ATPase in yeast Saccharomyces cerevisiae

63%
Oblak E., Bacal J., Lachowicz T. M.
Cellular and Molecular Biology Letters
|
2000
|
tom 05
|
nr 3
A quaternary ammonium salt, dodecyloxycarboxymethyl N, N, N - trimethyl ammonium chloride (IM), inhibits glucose-stimulated proton extrusion in yeast cells. The IM-resistant mutant (IMR) and pmal mutant are less sensitive to this inhibition. The inhibition of amino acids uptake by IM depends on repressed or derepressed conditions. IM treatment of yeast cells leads to a change of internal pH in a quinacrine fluorescence test.
14

Effect of selected ammonium salts on properties of BLMs

51%
Sarapuk J., Przestalski S., Witek S.
Postępy Biologii Komórki
|
1989
|
tom 16
|
nr 1
15
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The influence of bentonites modified with quaternary ammonium salts on biocidal properties of compositions of water-dilutable paints and lacquers, and mineral plasters

51%
Oleksy M., Heneczkowski M., Galina H., Lecka-Szlachta K.
Drewno. Prace Naukowe. Doniesienia. Komunikaty
|
2010
|
tom 53
|
nr 184
The research led to the obtainment of compositions of water-dilutable paints and lacquers as well as mineral plaster with the additive of nanofiller called Nanobent ® (bentonite modified with quaternary ammonium salt) which is a commercial product of ZGM Zębiec near Starachowice. The resistance of the abovementioned substances to mould fungi Aspergillus niger and Penicillium chrysogenum was tested. The best results were obtained for the composition with 3% additive of Nanobent ZR2 filler which practically completely inhibited the growth of mould fungi, even in the presence of whole culture medium containing glucose.
16

Influence of amphiphilic compounds on membranes

51%
Przestalski S., Sarapuk J., Kleszczynska H., Gabrielska J., Hladyszowski J., Trela Z., Kuczera J.
Acta Biochimica Polonica
|
2000
|
tom 47
|
nr 3
On the basis of Gortel & Grendel (J. Exp. Med., 1925, 41, 439-494) discovery, the importance of the lipid bilayer as an integral and indispensible component of the cell membrane is discussed. In particular, attention focuses on the interaction between membranes and amphiphilic substances. The effect on membranes of quaternary ammonium salts, both in the form of pesticides and oxidants as well as organic compounds of tin and lead are discussed in greater detail.
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