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Papaver somniferum produces secondary metabolites, which have important roles in their self-defence processes, in plant biochemistry and in allelochemistry. We can see that different stress effects change the quantity of alkaloids. The object of the experiments is, in what manner changes the content of alkaloids of poppy in case of irregular stress effects. Papaver somniferum (cv. 'Kék Duna', Budakalász) plants were grown for 2 months from seeds in quartz-sand (in natural light, temperature: 24-28 °C, in Knop's nutritive solution). In this paper we studied the alkaloid of poppy treated with two kind of stress factors: mycotoxin and drought, respectively. Both the quantity and the spectrum of alkaloids were measured after different separation procedures. Thin layer chromatography (TLC and HPTLC) and high performance liquid chromatography (HPLC) were applied. Content of the level of formaldehyde (HCHO) also increases in plants with different stress effects. Our presupposition is that the formation of methyl groups of poppy alkaloids takes place through HCHO. It gave us an opportunity to examine changing of formaldehyde (HCHO) level in biotic and abiotic stress situation. Formaldehyde in dimedone adduct form can be detected in injured tissues of Papaver somniferum. As a consequence, the stress effects can be detected in poppy plants by two kinds of method. At first we measured content of alkaloids. Drought stress produced a higher level of the alkaloids, but the mycotoxin stress did not show significant results.
Abstract
A new method has been developed for the separation and determination of low-level activity of strontium-90 through its daughter product yttrium-90 from natural water. Yttrium was separated and isolated from 1001 water at pH 5.5–5.7 by 8-quinolinol substituted silica gel. The yttrium was eluted with hydrochloric acid and precipitated with ammonium oxalate. The precipitate of yttrium oxalate was counted with a low-background beta-counter. The recovery of yttrium-90 is (64±4)% (n=5).
Certain classes of bioactive compounds can be separated using planar chromatography. Some biological effects (e.g. antibacterial) of these compounds can be investigated directly by examining the growth of a test organism on a specially treated sorbent of thin layer chromatography (TLC). A special method of detection, direct bioautography, is suitable for studying the antimicrobial activity of plant extracts of natural origin by using TLC. Zones of inhibition are visualised by use of a dehydrogenase-activity-detecting, tetrazol-type reagent. Zones of inhibition appeared as pale spots separating well from the dark background. The antibacterial effect of the main essential oil components of some Thymus taxa, as well as that of two antibiotics (streptomycin sulphate and gentamycin) known and applied in practice was investigated against plant pathogenic bacteria. Results showed that thyme essential oil and its components inhibited the growth of test bacteria, but not so considerably as the antibiotics applied. Compositions of the essential oils were analysed by gas chromatography (GC). It could be verified that among the essential oil components, thymol and carvacrol had the strongest inhibitory effect.
The crystal data of theα- andγ-modifications of KH(IO3)2 were determined. The rhombicβ-modification which has been described by earlier authors could not be obtained. In the course of thermal decomposition both crystal types release water, then I2O5 and O2, leaving a residue of KI. As an intermediate, K2I4O11 is formed. The temperatures of the DTA and DTG peaks of theα- andγ-modifications, were found to be different.
Commercial sodium caseinate isolate (SCI) was hydrolysed with either protease Subtilisina carlsberg - Alcalase 2.4 FG (purchased from Novo Nordisk), pronase from Streptomyces griseus, and papain EC 3.4.22.2 (both from Sigma) in a two-step process to determine the changes in the immunoreactivity of a-, ß- and ?-casein. Enzymatic hydrolysis of SCI was performed by pH-stat method. Hydrolysates were analysed using IEF, SDS-PAGE, 2D electrophoresis, FPLC-gel permeation chromatography. Immunoreactive properties of peptide fractions separated from the hydrolysates by FPLC were determined using dot-immunobinding and ELISA methods. The two-step process was observed to be effective in reduction of casein fractions immunoreactivity, however, allergenic epitopes were still present in all peptide fractions.
The authors’ aim is to reveal the reflection of Hungarian political and economic transformation in the public health nutrition during the last two and a half decades. Results of the four representative, nationwide dietary surveys completed in this period have been analysed for macro-, micronutrient intakes and overweight/obesity. The food consumption-related vital statistics provided by Hungarian Central Statistical Office were also analysed and compared. There are certain signs of favourable improvements: slight decrease of energy intake in females, growing share of plant protein, less saturated, more polyunsaturated fatty acid intake, less sugar. These findings are in parallel with some positive general statistical issues: the extension of life expectancy, lesser acute myocardial infarction, atherosclerosis and stomach cancer mortality, more vegetables and fruit, lesser lard, more oil consumption. On the other hand, there are several detrimental nutritional issues that influence the health status of Hungarian population: still high energy, fat and cholesterol intake, low complex carbohydrates, too much sodium (salt), insufficiencies in some vitamin, macro- and microelements intake. The number of overweight/obese people takes up fairly high level. The surveys somewhat revealed the role of nutrition in the health status of population and now a particle of possibility for its improvement is available
Komárek, J. and Anagnostidis, K. (2005): Cyanoprokaryota. 2. Teil: Oscillatoriales. - In: Büdel, B., Krienitz, L., Gärtner, G. and Schagerl, M. (eds): Süßwasserflora von Mitteleuropa, Band 19/2. Spektrum Akademischer Verlag, Elsevier GmbH, München, 759 pp.; Ross, I. A. (2005): Medicinal plants of the world - chemical constituents, traditional and modern medicinal uses. Volume 3. - Humana Press, Totowa, New Jersey, 623 pp. (ISBN 1-59259-887-0); Siver, P. A., Hamilton, P. B., Stachura-Suchoples, K. and Kociolek, J. P. (2005): Diatoms of North America: The freshwater flora of Cape Cod, Massachusetts, U.S.A. - In: Lange-Bertalot, H. (ed.): Iconographia Diatomologica. Annotated Diatom Micrographs. Vol. 14. A. R. G. Gantner Verlag K. G. Ruggel, 463 pp.;
