Search Results

You are looking at 41 - 50 of 68 items for

  • Author or Editor: K Szabó x
  • Refine by Access: All Content x
Clear All Modify Search

The terricolous species Cladonia foliacea (Cladoniaceae, lichenised Ascomycota) widely distributed in open, dry lowland steppe and rocky mountain grassland vegetation in Europe was chosen as a potential test organism for ecological experiments, since their thalli are producing cortical solar radiation-protective and UV screening pigment dibenzofuran usnic acid and medullary secondary substance depsidone fumarprotocetraric acid. Significant seasonal differences were found in the amounts of lichen secondary metabolites analysed by HPTLC and HPLC-PDA between summer and winter collected thalli in sandy grassland area in Hungary. The concentrations of usnic acid varied between 7.34 and 15.52 mg/g in summer collected samples and 13.90 and 21.61 mg/g in winter collected ones. A comparable amount (11.61±0.29 mg/g) was measured in pulverised samples. The concentrations of fumarprotocetraric acid varied between 0.60 and 3.01 mg/g in summer collected samples and 2.26 and 5.81 mg/g in winter collected thalli. A comparable amount (2.45±0.21 mg/g) was found in pulverised samples. The range of concentration values is comparable with data known from lichens. A higher amount of usnic acid is produced in winter probably to ensure sufficient protection also for summer. The fumarprotocetraric acid content of the medulla might contribute to the solar irradiation reflecting role of the pale lower surface lobes turning upwards in dry condition.

Open access
Acta Physiologica Hungarica
Authors:
Éva Polyák
,
K. Gombos
,
B. Hajnal
,
K. Bonyár-Müller
,
Sz Szabó
,
A. Gubicskó-Kisbenedek
,
K. Marton
, and
I. Ember

Artificial sweeteners are widely used all over the world. They may assist in weight management, prevention of dental caries, control of blood glucose of diabetics, and also can be used to replace sugar in foods. In the animal experimentation mice were given oral doses of water solutions of table top artificial sweeteners (saccharin, cyclamate based, acesulfame-K based, and aspartame) the amount of maximum Acceptable Daily Intake (ADI) ad libitum. The controls received only tap water with the same drinking conditions as the treated groups. The mice were fed chow ad libitum.We measured food intake and body weight once a week, water and solutions of artificial sweeteners intake twice a week. The data were analysed by statistical methods (T-probe, regression analysis).Consumption of sweeteners resulted in significantly increased body weight; however, the food intake did not change.These results question the effect of non-caloric artificial sweeteners on weight-maintenance or body weight decrease.

Restricted access
Acta Veterinaria Hungarica
Authors:
A. Beregi
,
Cs. Székely
,
L. Békési
,
Judit Szabó
,
V. Molnár
, and
K. Molnár

Radiodiagnostic methods have not been used previously for studying the anatomy and diseases of the swimbladder of freshwater fish species. In this study, the radiographic anatomy of the swimbladder and species-related differences in swimbladder structure were studied on plain radiographs taken of 12 Hungarian fish species of major economic importance. Changes observed by radiography were also studied by conventional parasitological methods. The radiodiagnostic method reported here appears to be a useful complement to diagnostic examinations that have been based merely on dissection so far. It enables evaluation of the pathological lesions in live condition, without causing damage to the fish.

Restricted access

The main objective of the DOSoReMI.hu (Digital, Optimized, Soil Related Maps and Information in Hungary) project is to significantly extend the potential, how demands on spatial soil related information could be satisfied in Hungary. Although a great amount of soil information is available due to former mappings and surveys, there are more and more frequently emerging discrepancies between the available and the expected data. The gaps are planned to be filled with optimized digital soil mapping (DSM) products heavily based on legacy soil data, which still represent a valuable treasure of soil information at the present time. The paper presents three approaches for the application of Hungarian legacy soil data in object oriented digital soil mapping.

Restricted access
Journal of Thermal Analysis and Calorimetry
Authors:
J. Bajdik
,
K. Pintye-Hódi
,
G. Regdon
,
P. Fazekas
,
P. Szabó-Révész
, and
I. Erős

Abstract  

Eudragit NE 30 D aqueous dispersion is a commonly used coating material, which contains methacrylate copolymers as film-forming agent and nonoxynol 100 as an endogenous emulsifier. The dissolution of the active ingredient from Eudragit NE-coated samples during storage is known to undergo a change. The crystallization of the emulsifier agent can play an important role in this. This polymer is not soluble in the gastrointestinal tract, but is permeable. Various parameters can influence the permeability of this film, e.g. via the tensile properties of the film. Change in the film thickness can cause the stretching of the film on a solid surface. Alterations in this physical parameter of the film were measured and the effects of different storage conditions were evaluated. The free film was prepared by spraying onto teflon. The crystallization of nonoxynol was followed via the changes in the DSC curve of the free film. A relationship was found between the film thickness and the crystallization of nonoxynol. It was established that the different storage conditions influence these changes. The temperature and the air humidity are important in this phenomenon. Lengthening of the storage time increased the difference in film thickness and crystallisation of emulsifier.

Restricted access
Journal of Thermal Analysis and Calorimetry
Authors:
J. Bajdik
,
K. Pintye-Hódi
,
Cs. Novák
,
P. Szabó-Révész
,
G. Regdon
,
I. Erős
, and
G. Pokol

Abstract  

Dimenhydrinate is a heat-sensitive antihistamine with a low melting point. The heat-sensitive feature is of importance if direct compression is used. Direct measurement of the heat originating in the texture of tablets during compression is very difficult. Thermoanalytical methods were used as indirect methods to describe the changes in material properties at high temperature: differential scanning calorimetry, thermomicroscopy and thermogravimetric analysis. Film coating method is widely used in pharmaceutical technology. A fluidized bed apparatus was applied to coat the crystals. The coating film forming agent was hydroxy-propyl-methylcellulose (HPMC), which is a gastric-soluble polymer. Thermoanalytical measurements reveal that dimenhydrinate crystals are sensitive to heat. Film coating method does not alter the shape of the DSC curve of dimenhydrinate, but increases the melting point. The presence of a macromolecular film reduces the thermal conductivity, because it separates the particles.

Restricted access
Journal of Thermal Analysis and Calorimetry
Authors:
Á. Beretzky
,
P. Kása
,
K. Pintye-Hódi
,
J. Bajdik
,
P. Szabó-Révész
, and
I. Erős

Abstract  

The flowability of needle- or plate-shaped crystals is very poor and the direct compression of these crystals is difficult. Commercial phenylbutazone consists of needle crystals and it has three polymorphs.The aim of this work was to investigate the solid-state thermal stability of phenylbutazone at condition of the pelletization process (40°C; 60 min). The other aim was the preparation of phenylbutazone pellets with centrifugal granulator.Based non the flowability and the other parameters of, the pellets, they are suitable for capsule filling or tabletting. The centrifugal granulation and the conditions were favourable for the preparation of pellets from phenylbutazone in the form of needle crystals.

Restricted access
Acta Alimentaria
Authors:
K. Szekér
,
J. Beczner
,
A. Halász
,
Á. Mayer
,
J.M. Rezessy-Szabó
, and
P. Gálfi

The adhesion of twenty-six Lactobacillusstrains to two intestinal cell lines (Caco-2P and IEC-18) and 21 Bifidobacteriumstrains to Caco-2P cells was investigated. Non-specific adherence was determined on the surface of culture plates. The effect of short chain fatty acids (SCFA) on epithelial cells, and bacterial adhesion were investigated by Na-n-butyrate treatment. The adherence of LAB and bifidobacteria greatly varied in a strain-dependent manner. The adherence of LAB was better to IEC-18 cells than to Caco-2P cells, and bifidobacteria adhered better to Caco-2P cells than the LAB. Some strains adhered well or even better to the background than to the cells, which queries the specificity of adhesion of these strains. Na-n-butyrate treatment stimulated the differentiation of IEC-18 cells and therefore increased the number of adherent bacteria, probably because only the cell surface increased not the number of epitopes.

Restricted access

Ground ivy (Glechoma hederacea L.) is one of the prosperous plants for the food-industry as natural antioxidant. This fact led us to examine the chemical diversity of six ground ivy populations situated in different natural habitats and to analyse the effect of the harvesting time. Total phenolic content, chlorogenic acid, and rutin content, as well as the antioxidant capacity showed significant differences due to the harvest time. The highest total phenol content (115 mg g–1 GAE) and the strongest antioxidant activity (53.3 mg g–1 AAE) were measured in the population originated from Budapest (GLE 6), harvested in July. The highest chlorogenic acid (357 mg/100 g) and rutin (950 mg/100 g) contents were detected in the July harvested samples from the Soroksár Botanical Garden population (GLE 1). According to our results, the collection time has significant effect on the total phenolic content – first of all on the chlorogenic acid and rutin accumulation levels of ground ivy, while the influence of the habitat seems to be less important.

Restricted access
Acta Alimentaria
Authors:
E. Szabó
,
É. Gelencsér
,
E. Kovács
,
A. Jánosi
,
K. Takács
, and
E. Kiss

In our research we studied the occurrence of the main apple allergen coding gene-families (Mal d 1, Mal d 2, Mal d 3, Mal d 4) in 16 different and most preferably consumed apple varieties. After the DNA isolation by Wizard method the simple PCR reaction was used to examine the apple allergen-coding genes. To identify the presence of the four allergenic protein-coding genes two primer pairs were chosen. The presence of these allergens in most apple varieties could be confirmed. According to our results two varieties — Jonathan and Granny Smith — were found to contain the lowest amount of the coding genes of the allergenic apple proteins studied by us. Besides this, polymorph pattern was obtained by the use of Mal d 1 primer, which may lead to determine apple varieties with small amount of Mal d 1 allergens.The confirmation study of the presence of potential apple allergens by RNA and protein techniques is our plan in the near future.

Restricted access