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OIE Terrestrial Animal Health Code. 13th and 14th editions (2004 and 2005) from the World Organization for Animal Health, Paris, France. 14th edition, 2005. ISBN 92-9044-635-8. Ref.: A 135; Jacques Euzéby, Gilles Bourdoiseau, Claude-Marie Chauve: Dictionnaire de parasitologie médicale et vétérinaire (Dictionary of Medical and Veterinary Parasitology). Éditions Tec & Doc - EM Inter - Lavoisier. Cachan, France, 2005. 492 pages. ISBN 2-7430-0705-2;

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Acta Alimentaria
Authors:
M. Nagy-Gasztonyi
,
E. Biekman
, and
B. Krebbers

The combination of lactofermentation and enzyme-treatment (Rohament-PL as endo-polygalacturonase and the mixture of Rohament-PL and Rohalase 7069 as cellulase) of sliced carrot and orange juice resulted in a homogeneous product, with pleasant organoleptic features, after 18 h fermentation period. Two ways of inoculation were applied with Lactobacillus plantarum. The addition of Rohament-PL, even at 150 mg kg-1 concentration, simultaneous inoculation with Lactobacillus plantarum (circumstances: 28 °C, 80 r.p.m. shaking) promoted the growth of lactobacilli. By 42 h fermentation time LAB count increased up to 3.2-4.8´109 cm-3. Furthermore the surface colour of the samples was more intensive (higher L-, a- and b-values) than without Lactobacillus plantarum inoculation. The application of Rohament-PL (50-100 mg kg-1) resulted in a homogeneous carrot puree, the combination of Rohament-PL (150 mg kg-1) and Rohalase 7069 (150 mg kg-1) in the process gave a more fluid product, as proved by the lower specific viscosity values.

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The goal of this study was to improve the diagnostic applicability of genus- and serovar- (S. Enteritidis and S. Typhimurium) specific PCR systems in screening faecal and caecal samples of poultry, poultry feed and poultrymeat for Salmonella, by keeping the opportunity to obtain Salmonella cultures from positive samples. Peptone broth pre-enrichment cultures of the samples were tested by PCR. In faecal and caecal samples from broiler chicks a strong inhibitory action was frequently observed. This could be reduced markedly by the addition of bovine serum albumin (BSA) acting as amplification facilitator. The results of testing pre-enrichment cultures from artificially contaminated faecal, poultry feed and poultrymeat samples (using S. Enteritidis, S. Typhimurium and S. Hadar as contaminants) suggest that the sensitivity of the above systems is 101-102 CFU g-1 sample. The testing of 95 caecal samples from slaughtered chicks resulted in 49% culture-positive and 76% PCR-positive samples. The suitability of a generic real-time PCR for testing faecal samples of poultry was also studied. Its detection limit for these samples was found to be lower than that of the diagnostic PCR system. Both methods reduced the time required for Salmonella detection to 24-30 h, and the advantage of the real-time PCR was its increased sensitivity. We have established a diagnostic and a real-time PCR system for rapid and reliable genus- and serovar- (S. Enteritidis and S. Typhimurium) specific detection of Salmonella for monitoring purposes in the poultry food chain. Sensitivity is equal to, or higher than, that of the standard bacterial culture method, and the method still provides the Salmonella culture if needed.

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Analysis of flagellin genes was carried out on strains of Salmonella Typhimurium, Salmonella Hadar, Salmonella Abortusequi, Salmonella Enteritidis and Salmonella Gallinarum serovars, using a PCR system designed in this study. The purpose of these studies was to explore the flagellin genes of biphasic and monophasic Salmonellae for future targeted genetic interventions. The PCR primers were designed for two different structural genes of flagellin (fliC, fljB), for the repressor of fliC (fljA), for the operator region of fliC, and for the invertase system responsible for phase variation in Salmonella (hin, hixL, hixR). PCR analysis revealed that all of the examined genes (fliC, fliC-operator, fljB, fljA, hin, hixL, hixR) were present in all S. Typhimurium (n = 10)and S. Hadar (n = 10) strains tested. The results obtained on S. Typhimurium and S. Hadar strains confirmed their biphasic character at DNA level. However, the S. Enteritidis (n = 46) and S. Gallinarum (n = 5) strains lacked the invertase system (hin, hixL, hixR) as well as the fljA and fljB genes, while fliC and its operator were detectable. Consequently, the S. Enteritidis strains could only express fliC gene resulting in phase H1 flagellin. The examined S. Gallinarum strains were also demonstrated to have a cryptic flagellin gene (fliC). On the other hand, PCR results on S. Abortusequi (n = 2) indicated that both flagellin genes (fliC, fljB) and the whole phase variation system were present in both strains tested but only the H2 phase gene (fljB) was expressed. The phenotype of these strains could be clarified by motility test and/or by classical flagellar serology. The findings are also substantiated by the results of serovar-specific PCR for S. Typhimurium and S. Enteritidis. In conclusion, the PCR system developed in this study proved to be suitable for characterisation of Salmonella flagellin genes and confirmed serological results regarding all S. Typhimurium, S. Hadar and S. Enteritidis strains. This system could also identify cryptic flagellar genes of S. Abortusequi and S. Gallinarum.

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The study area is the peaty bed of Navad-patak mire situated in the North-Eastern Alföld, on the Bereg plain, which is slightly investigated area. The purpose of our research was to reconstruct the recent vegetation dynamic processes of the mire from 1950 till 2005. Beside the aerial photos we used the ERDAS Imagination remote sensing program, and made digital photo interpretation. We divided the vegetation history into three parts. In the first period, the nutrient load of the mire was increased, peat decaying and foresting processes started, the open peat-moss dominated associations ( Eriophoro vaginati-Sphagnetum, Carici lasiocarpae-Sphagnetum ) were disappeared. In the second period the expansion of the forest vegetation continued, the species composition transformed, and the characteristic species of the mentioned associations ( Eriophorum vaginatum, E. angustifolium, Carex lasiocarpa, Drosera rotundifolia, Sphagnum magellanicum ) were all disappeared. The third period starts with the artificial flooding in 1994. In the beginning the peat-mosses were all extinct, floating mires appeared immediately and their quick succession started and still runs. The fourth period would be start with the appearance of peat-mosses.

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During the ageing in barrels, the contact with the fine lees triggers several processes in wine. Lees has a reductive effect by absorbing dissolved oxygen and reducing the amount, which will remain in the wine. At present, minimizing the addition of sulphur dioxide is the trend in all viticultural areas. In this study, the effect of various sulphur dioxide levels was monitored in presence of the lees to determine which dose is appropriate to provide the protection of susceptible white wine against oxidation.

Without SO2 protection, the rH and redox potential changed slightly, so the level of dissolved oxygen seemed to be controlled during the ageing period by the lees, though the antioxidant effect of lees in itself was not appropriate to protect the polyphenol content from chemical oxidation, which led to considerable browning. With the addition of a lower amount of SO2 — 40 mg l2, the lees is already able to protect the white wine samples in all aspects.

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