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Thirty-three varieties of dairy products were analysed for fat and cholesterol contents, and a high correlation (r=0.983) was found between these two compositional attributes. Cholesterol concentration was independent of processing factors such as heat-treatment of the raw material, use of starter culture, type of the starter organisms employed and whipping or flavouring of the product. The non-fat varieties of fluid, fermented and dried milks showed significantly increased cholesterol-to-fat ratios compared to the other products tested because they contained considerable amounts of small fat globules and, therefore, had a large surface area with cholesterol bound to the fat globule membranes. The results of this study may be useful when establishing dietary guidelines for the general public according to health concerns, when formulating diets for population groups with special requirements or when assessing fat and cholesterol intakes in epidemiological studies aimed at investigating the relationship between diet and health.

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Acta Alimentaria
Authors:
V. Kapcsándi
,
A.J. Kovács
,
M. Neményi
, and
E. Lakatos

The aim of our experiments was to demonstrate the non-thermal effect of microwave treatment on Saccharomyces cerevisiae fermentation activity. A method was developed for studying the effects of various treatments in the course of must fermentation. The raw material (must) was treated in different ways: (i) heat transfer; (ii) microwave treatment; (iii) inoculation with yeast, and (iv) their combinations. The results of the treatments were compared with respect to alcohol concentration, sugar content, and acidity. The results proved that sugar content of the treated samples rapidly decreased compared to the control sample, and fermentation time was 40% shorter in the fastest case. These results can be explained by the yeast inoculation and microwave treatment. Due to non-thermal effects, fermentation capacity increased by about 30%, while the energy consumption decreased.

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The responses of the snail central neurons (Helix pomatia, Lymnaea stagnalis) and the isolated Helix heart were characterized evoked by cyanobacterial extracts (Cylindrospermopsis raciborskii ACT strains) isolated from Lake Balaton (Hungary). The nicotinergic acetylcholine (ACh) receptors in the CNS (both excitatory and inhibitory) were blocked by the extracts of ACT 9502 and ACT 9505 strains and the anatoxin- a (homoanatoxin-a) producing reference strain of Oscillatoria sp. (PCC 6506), similar to the inhibitory effects of the pure anatoxin-a. The enhancement of the ACh responses by the ACT 9504 extract suggests additional, probably acetylcholine esterase inhibitory mechanisms. On the isolated Helix heart the crude ACT 9505 and PCC 6506 extracts evoked frequency increase and transient twitch contraction, opposite to the ACh evoked heart relaxation. Anatoxin-a similarly contracted the heart but did not increase its contration frequency. These data suggest the involvement of some non-cholinergic mechanisms, acting very likely by direct modulation of the electrical or contractile system of the isolated heart. Diversity of the effects evoked by the cyanobacterial extracts in the CNS and heart suggest pharmacologically different neuroactive components among the secondary metabolites of the cyanobacteria acting on both (anatoxin-a like) cholinergic and (unidentified) non-cholinergic receptors.

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Acta Veterinaria Hungarica
Authors:
A. Molnár
,
P. Sarlós
,
G. Fáncsi
,
J. Rátky
,
Sz. Nagy
, and
A. Kovács

Semen of an infertile Dutch White (Saanenthal) goat buck was examined. Light and electron microscopic examinations showed aberrations of the sperm tails resembling the so-called Dag or Dag-like defects described in several cattle breeds. Ejaculated semen showed that virtually all of the cells had strongly coiled or broken tails, or fractured midpieces. Ultrastructural investigations by transmission electron microscopy (TEM) showed uneven distribution of the mitochondria in the midpiece. Coiled tails were encapsulated by a common membrane, and dislocated axial fibres and different membranous structures were also present. The ultrastructural characteristics of the defective sperm tails, the missing parts of the axial fibre bundle and the misalignment of the mitochondria indicate that this first case reported in goat is similar to the Dag-like defect in cattle.

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Acta Biologica Hungarica
Authors:
Á. Hegyi
,
B. Urbányi
,
M. Kovács
,
K. Lefler
,
J. Gál
,
Gy. Hoitsy
, and
Á. Horváth

The transportation of rainbow trout in the presence of the anesthetic clove oil was investigated. Before the transportation tests, an acute experiment was conducted to verify that removal of the fish from the water for one minute does not significantly increase the glucose or cortisol concentration of the blood plasma. In the main experiment two different transportation conditions were compared: transport in water only and in water with anesthetic. During transportation without addition of clove oil, blood plasma glucose and cortisol concentrations changed significantly. The concentration of glucose increased from 4.92 mmol/L prior to transportation to 6.16 mmol/L and values similar to the initial ones (4.95 mmol/L) were observed 5 hours after transportation. Concentration of the stress hormone cortisol increased from the initial 37.2 ng/mL to 89.2 ng/mL and returned to a value of 36.1 ng/mL 3 hours post transportation. Respective values of glucose concentration have not changed significantly during transportation in the presence of clove oil (4.3; 4.4; 4.4 mmol/L), whereas those of cortisol showed a slight decrease with the passing of time (28.1; 26.7; 20.18 ng/mL). Results show that transportation stress can significantly be reduced by the use of anesthetics.

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Efforts have been made to predict the sensory profile of coffee samples by instrumental measurement results. The objective of the work was to evaluate the most important sensory attributes of coffee samples prepared from ground roasted coffee by electronic tongue and by sensory panel. Further aim was to predict the Arabica concentration and the main sensory attributes of the different coffee blends by electronic tongue and to analyze the sensitivity of the electronic tongue to the detection of poor quality coffee samples. Five coffee blends with known Arabica and Robusta concentration ratio, five commercially available coffee blends and a poor quality coffee were analyzed. The electronic tongue distinguished the coffee samples according to the Arabica and Robusta content. The sensory panel was able to discriminate the samples based on global aroma, bitterness and coffee aroma intensity (p < 0.01). The Arabica concentration was predicted from the electronic tongue results by PLS with close correlation and low prediction error. Models were developed to predict sensory attributes of the tested coffee samples from the results obtained by the electronic instrument.

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The contribution contains of the geophysical data and their interpretation. Interpretation of geophysical fields in compliance with the geological structure and geodynamics EMO far region contributes significantly to development of  seismo-tectonic model. The model represents the correlation between seismic activity and geological-tectonic setting. The achieved seismo-tectonic model in fact reasons all recorded seismic events in the area and points out to a seismic activity decrease towards the Danube Basin center,  thereof, there being situated the EMO locality.

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To determine the prevalence of wheat sensitivity in a randomly selected Australian population, a study was carried out on sera samples of the Geelong Osteoporosis Study (GOS) age-stratified cohorts of men and women who were randomly selected from electoral rolls for the Barwon Statistical Division (n = 1145). The human sera were analysed by ELISA-based method using the ImmunoCAP 100 instrument (Phadia, Sweden). IgE from human sera were bound to the wheat (f4) and milk (f2) allergens that have been previously coated on the ImmunoCAPs. The number of IgE wheat and milk RAST positive individuals was determined. In order to relate the increased IgE immuno-reactivity to allergen symptoms, a questionnaire was established and sent to the blood donors and 974 individuals responded. Of these (n = 974) 147 individuals (15.1%) reported symptoms caused by wheat consumption, 179 (15.6%) and 112 (9.8%) sera showed RAST positive results (IgE > 60 response units) in wheat and milk RAST tests, respectively. However, only 2.5% of those participants with symptoms related to wheat had positive IgE values indicating that the relationship is complex: a large proportion (12.7%) of the investigated population might suffer from other wheat related disorders (i.e. not IgE mediated), such as celiac disease, non-celiac reaction to gluten, reaction to fructans for those with irritable bowel syndrome as well as other factors. For the 13.2% who showed raised IgE antibody levels without symptoms we postulate that these individuals have latent wheat sensitivity with the potential of developing symptoms sooner or later.A comparative study to investigate the immune reactivity of human IgE against wheat and spelt antigens was carried out using the sera of 73 patients found to be RAST positive for wheat. Of these 63% (n = 50) showed a higher IgE immune reactivity against wheat, while 30% (n = 24) showed higher IgE response against spelt antigens, the remaining 7% have indifferent responses against both antigens. Since the provided Phadia wheat and spelt antigens used in this study originated from Europe, Australian wheat and spelt varieties were also used to prepare antigens in order to investigate the response of Australian sera to local wheats. It was found that the immune reactivity of IgE wheat positive sera from a normal Australian population is lower for spelts compared to wheats regardless of their origin but much lower against an Australian spelt containing a mutation in its expansin gene. Aclinical feeding trial would be necessary to confirm if this difference in immune reactivity between spelt and wheat is consistent with a difference in allergenicity.

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A simultaneous live/dead and acrosome staining, originally described for domestic mammals, was successfully applied on red deer (Cervus elaphus) and fallow deer (Dama dama) spermatozoa collected from the cauda epididymidis and vas deferens of shot stags. The staining is simple enough for routine application. Seven classes of spermatozoa were distinguished in the smears of frozen/thawed semen samples. Morphology, including cytoplasmic droplets, was evaluated as well. Percentage of live cells with intact acrosomes and with no other morphological aberrations might be a practical index of semen quality.

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