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- Author or Editor: S. Szabó x
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Near-infrared (NIR) spectrophotometers with different optical arrangements were used to measure the diffusely reflected electromagnetic radiation of different types of food additives in polyethylene (PE) foils. Eight compounds, frequently used in food process – but also in other industries –, were measured by different NIR spectrophotometers. The detected (‘as is’) and mathematically transformed (by scatter correction, second derivative combined with smoothing) NIR spectra were processed with multivariate data analysis (MDA). In this matter, unsupervised methods like principal component analysis (PCA) and cluster analysis (CA) were used, which techniques do not require prior information and reference measurements. The aim of the present study was to distinguish food additives by the help of the applied chemometric methods based on NIR spectra detected via the PE foils. Results indicated that distinction of different food additives and compounds with NIR methods is possible not only with the conventional sample preparations and handlings, but also without breaking the packaging.
Within a survey made of Hungarian awareness of, attitudes towards, and preferences for food labels and pricing, this study focused on consumers’ reactions to quality and country of origin labels. Data were collected with a standard questionnaire, face-to-face interviews (1000 participants) in the respondents’ home. It became obvious that consumers were looking for information about quality (rating its importance at 4.04) on packages, but information about origin (3.94) and production (3.89) was also important to them. The capability of respondents to spontaneously recall country of origin and quality labels was very limited: 35.5% of all respondents could not name any such labels. The best known label was “Hungarian Product” (30.5%), which was recognized by up to 90% of the respondents after they were shown it. Many consumers were ready to pay premium for products bearing this label (31.7%). According to our results, information about quality is important to consumers, but they do not look for it deliberately, and only a few consumers ascribe a higher value to products with labels bearing this information. There is a pressing need to increase consumers’ confidence for trademarks through dissemination of reliable information.
Studies addressing the question of how communities develop reported contrasting temporal patterns of species associations during succession. Several hypotheses were formulated about succession, but a general explanation of community assembly is missing. We analysed trends of species associations during old-field succession in two contrasting habitats: the first with chernozemic brown forest soil and temperate climate, and the second with sand soil and dryer climate. Significant pair-wise associations were calculated across a range of spatial scales. Comparing the two succession seres, one under harsh and the other under favourable environment, we attempted to make generalisations about species relation patterns. We found no trend but fluctuation in the level of community organization during succession. None of the existing succession models explained our results about changes in spatial structure of grassland communities during succession. Fluctuation in the number of significant associations was more intense and took longer under less favourable environmental conditions. Our results suggest that the stressed habitat type posed stronger constraints on species coexistence during succession than the favourable habitat did, but validating this hypothesis needs further investigations.
The aim of this study was to investigate the differences in the proteome patterns of musculus longissimus dorsi between Charolais bulls slaughtered at 500 kg and 700 kg live weight using two-dimensional difference in gel electrophoresis (2D-DIGE) and liquid chromatography-mass spectrometry (LC-MS). Three hundred fifty protein spots were visualised on gels of which 10 showed different expression levels (P<0.05) between groups. After mass spectrometric analysis of spots, beta-enolase (ENO3) in five different spots, alpha-enolase (ENO1), triosephosphate isomerase (TPI1) in two different spots, alpha-actin (ACTA1), and heat shock protein beta-1 (HSPB1) were identified. ENO3, ENO1, TPI1, and ACTA1 had higher expression levels in bulls of 700 kg live weight group. ENO3, ENO1, and TPI1 are involved in energy metabolism, while ACTA1 is a structure protein in skeletal muscle. Up-regulation of heat shock protein beta-1 (HSPB1), which protein is reported to have correlation with tenderness, was observed in 500 kg weight group. Our result demonstrates that proteomic tools are useful in identifying markers associated with muscle development.
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.
An undescribed symptom caused by Fusarium graminearum was detected in wheat fields showing masses of orange sporodochia on the node and neighbouring stem tissue. Normally the head above infected nodes dies and only chaff is harvested. This is the first formal description of this type of stem infections caused by F. graminearum . The economic importance of these disease symptoms need further evaluation.
Abstract
Serum amyloid P component (SAP), a member of the innate immune system, does not penetrate the brain in physiological conditions; however, SAP is a stabilizing component of the amyloid plaques in neurodegenerative diseases. We investigated the cerebrovascular transport of human SAP in animal experiments and in culture blood-brain barrier (BBB) models. After intravenous injection, no SAP could be detected by immunohistochemistry or ELISA in healthy rat brains. Salmonella typhimurium lipopolysaccharide injection increased BBB permeability for SAP and the number of cerebral vessels labeled with fluorescein isothiocyanate (FITC)-SAP in mice. Furthermore, when SAP was injected to the rat hippocampus, a time-dependent decrease in brain concentration was seen demonstrating a rapid SAP efflux transport in vivo. A temperature-dependent bidirectional transport of FITC-SAP was observed in rat brain endothelial monolayers. The permeability coefficient for FITC-SAP was significantly higher in abluminal to luminal (brain to blood) than in the opposite direction. The luminal release of FITC-SAP from loaded endothelial cells was also significantly higher than the abluminal one. Our data indicate the presence of BBB efflux transport mechanisms protecting the brain from SAP penetration. Damaged BBB integrity due to pathological insults may increase brain SAP concentration contributing to development of neurodegenerative diseases.
