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Pantev A Valcheva R Danova S Ivanova I Minkov I Haertlé T Chobert JM 《International journal of food microbiology》2003,80(2):145-152
Lactic acid bacterium isolated from Bulgarian cheese and identified as Enterococcus faecium produces a small hydrophobic peptide substance (enterococcin A 2000) with broad spectrum of antimicrobial activity. The wide range of enterococcin antibacterial activity of this compound against Gram-positive, as well as against some Gram-negative bacteria, suggests a single mechanism of action. The mode of action of enterococcin A 2000 was studied in intact liver mitochondria and synthetic phospholipid liposomes used as model systems. Enterococcin A 2000 stimulated the ATPase activity in intact mitochondria. The kinetic curve of ATP hydrolysis differed from that obtained in presence of dinitrophenol (DNP) and showed a character similar to the ATP hydrolysis in the presence of classic ionophores. Enterococcin A 2000, when bound to synthetic phospholipid liposomes, permeabilized liposomes liberating the marker carboxyfluorescein (CF). 相似文献
75.
Thermal and elastic properties of poly(vinyl chloride) (PVC) + chlorinated polyethylene (CPE) blends
Robert?D.?MaksimovEmail author Tatjana?Ivanova Janis?Zicans Sophia?N.?Negreeva Egils?Plume 《Materials Research Innovations》2003,7(5):326-330
Eight types of PVC + CPE blends with different weight ratios (PVC/CPE = 100/0, 90/10, 80/20, 60/40, 40/60, 20/80, 10/90, and 0/100) are tested. Data on the heat conductivity, thermal diffusivity, and heat capacity of the blends investigated are reported. Primary attention is paid to the structural approach for effective elastic constants: bulk, shear, and Young's modulae. The blends are considered as random mixtures of two isotropic constituents. It is found that the elastic moduli may be well represented by the Kerner and Budiansky equations. 相似文献
76.
Sb2Te3–Bi2Te3 crystals (25–60 mol % Bi2Te3) doped with Bi2Se3 and excess Te were studied with the aim of identifying the optimal compositions for the p-legs of low-temperature coolers. The crystals were grown by the floating-crucible technique. Their transport properties were studied in the range 100–400 K. By measuring axial thermopower profiles, it was shown that increasing the Bi2Te3 and Bi2Se3 contents of the crystals has an adverse effect on their homogeneity. Crystals were prepared with a carrier concentration in the range (1–5) × 1019 cm–3 and a thermoelectric power above 200 V/K at room temperature and the highest thermoelectric figure of merit at temperatures below 200 K. The maximum temperature drops and thermoelectric figures of merit were calculated for low-temperature stages of magnetothermoelectric coolers with hot-junction temperatures of 200 and 170 K and Bi–Sb n-legs. 相似文献
77.
New Np(VI) and Pu(VI) dimolybdates Rb2NpO2(MoO4)2·H2O (I), Cs2NpO2(MoO4)2·H2O (II), Cs2PuO2(MoO4)2·H2O (III), and Rb2PuO2(MoO4)2·H2O (IV) were synthesized under hydrothermal conditions. The crystal structures of the compounds were determined, and their absorption spectra in the UV, visible, and IR ranges were measured. The compounds crystallize in the monoclinic system. Their crystal structure is based on [AnO2(MoO4)2]n2n– anionic layers (An = Np, Pu) formed by (AnO2)O5 pentagonal bipyramids and MoO4 tetrahedra, sharing common vertices. Each An atom in the layer is bonded to other five An atoms via MoO4 tetrahedra with the formation of a 43432 network. The effect of the ionic radius of the outer-sphere cation on the parameters of the crystal structure and features of the absorption spectra is discussed. 相似文献
78.
II Kalachev AN Baídus' OA Ivanova EA Ganina IA Boldyrev EA Svetoch 《Canadian Metallurgical Quarterly》1997,(6):32-37
Unlike the glanders agent, the superficial structures of the melioidosis agent were demonstrated to be responsible for marked was immunosuppressive activity. Some antigenic fractions suppressing the blast transformation of lymphocytes, reducing the count of T helpers and profoundly potentiating the infection in vivo were isolated from P. pseudomallei cells. The immunogenic and immunosuppressive activities of both agents' superficial structures were studied by high performance chromatography. Antigenic complexes that were able to protect immunized laboratory animals against fatal infections and to prevent bacterial carriage due to the activation of T cells and to the bacterial activity of macrophages were identified. A composition comprising several immunogens was found to provide an additive protective action against both causative agents. Therefore, the composition may be considered to be a prototype of a molecular antipseudomonadic vaccine. 相似文献
79.
Prevalence of risk of ischemic heart disease, such as nutrition and dyslipoproteinaemias are discussed. The interrelation of these risk factors with blood lipids was examined. It was found that risk factors are widespread, and population has low knowledge about their significance. Food, contained surplus of cholesterol, saturated fats, carbohydrates and deficiency of polyunsaturated fat acids increased atherogenic blood lipids and decreased antiaterogenic lipoproteins. 相似文献
80.
Emil Malchev Nikola Spassov Ghenov Nikolina Ivanova Ioncheva Stoyan Stoychev Tanchev Krassimira Kirilova Kalpakchieva 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1989,189(3):229-231
Summary The higher fatty acids of dried red pepper of the variety of Gorogled were identified by gas chromatography with using help of authentic compounds. Their amounts were determined using on absolute calibration method.The following acids were established: lauric, myrastic, palmitic, palmitoleic, stearic, oleic, linoleic, linolenic,arachidic and behenic acids. The results obtained from the quantitative measurements showed that linoleic, linolenic and palmitic acids amounted to 80% of the total acids.The quantitative changes of identified acids in red pepper, of dried at 60°, 70°, 80° and 90 °C red pepper and stored as dried red pepper and red pepper powder over a 6-months period investigated.The results show that under the drying temperatures applied the amount of all fatty acids decreased with an increase in the temperature. During a storage a period of 3 months the amount of the respective acids decreased while the process was the most expressed in red pepper dried at a temperature of t = 70 °C.After a 6-months storage period under the drying condition applied the dried red pepper contained a greater amount of fatty acids compared with stored for 3 months.
Identifikation und Veränderungen der höheren Fettsäuren von gemahlenem Paprika und von getrockneten ungemahlenen Paprikaschoten
Zusammenfassung Es wurden gaschromatographisch mit Hilfe von Vergleichsubstanzen die höheren Fettsäuren, die im gemahlenen Paprika (Sorte Gorogled) enthalten sind, identifiziert. Die Mengen wurden nach der Methode der absoluten Kalibrierung bestimmt. Es wurden folgende Säuren festgestellt: Laurinsäure, Myristin-, Palmitin-, Palmitoolein-, Stearin-, Olein-, Linol-, Linolen-, Arachin- und Behensäure. Die quantitativen Ergebnisse zeigen, daß die Menge der Linolen-, Linol- und Palmitinsäure 80% der Gesamtsäurenmenge darstellt. Es wurden die quantitativen Veränderungen der Fettsäuren von Paprika (Sorte Gorogled) bei Temperaturen von 60 °, 70 °, 80 ° und 90 °C, getrocknet und als getrockneter ungemahlener bzw.gemahlener Paprika, gelagert und innerhalb von 6 Monaten in Abständen von 3 Monaten verfolgt. Bei den angewendeten Trocknungstemperaturen nimmt die Menge der einzelnen Fettsäuren in dem getrockneten ungemahlenen Paprika mit Erhöhung der Trocknungstemperatur ab. Die Lagerung des getrockneten ungemahlenen Paprikas innerhalb von 3 Monaten führt zur Abnahme der einzelnen Fettsäuren, wobei dieser Prozeß am stärksten bei einer Trocknungstemperatur von 70 °C verläuft. Nach einer 6monatigen Lagerung des getrockneten und ungemahlenen Paprikas, nach Trocknung und bei den o. g. vier Temperaturen, ist die Menge der Fettsäuren höher im Vergleich zu jener der Fettsäuren in getrocknetem ungemahlenem Paprika nach 3 Monaten. Nach 3 Monaten enthält der gemahlene Paprika weniger Fettsäuren als der getrocknete und ungemahlene Paprika.相似文献