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Our knowledge on the presence of mycotoxin producing fungi and mycotoxins in food commodities in the last decade in Hungary has been summarized in this review. Among the mycotoxin producing fungi, detailed data are available for Fusarium species in cereals, and mycotoxigenic Aspergillus species in different food commodities including coffee, raisins and spices. Ochratoxin concentrations above the tolerable limit have mostly been detected in imported products such as peanuts and coffee. Ochratoxin levels close to the tolerable limit have been observed in Hungarian red peppers. Besides, ochratoxin A has also been detected in Hungarian wine, beer and raisins. Aflatoxins are usually detected in considerable quantities only in imported agricultural products in Hungary, while patulin concentrations were usually below the allowable limit in Hungarian apple juice concentrates. In the future, continuous sampling and analysis of foods and feeds are required to ensure consumer safety in Hungary.

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Ochratoxin A is a mycotoxin produced by Aspergillus and Penicillium species. This mycotoxin is a common contaminant of various foods including cereal products, spices, dried fruits, coffee, beer and wine. Besides cereal products, goods of grape origin contribute significantly to ochratoxin exposure of humans. The ochratoxin content and mycobiota of raisins purchased in Hungarian outlets were examined in this study. Ochratoxin A content was examined by an immunochemical technique, and the results were confirmed by HPLC analysis using fluorescent detection. Altogether 20 raisin samples were analyzed. Ochratoxin A was detected in all but two samples with ochratoxin concentrations ranging from 0 to 6.2 mg kg-1. The most heavily contaminated raisin sample came from Iran. However, none of the raisins contained ochratoxin A above 10 mg kg-1, the European Community maximum allowable limit in raisins. The mycobiota of raisin samples was also examined to clarify which species could be responsible for ochratoxin A contamination. All except three raisin samples were contaminated with black aspergilli, some of which produced ochratoxin A. Besides A. carbonarius, ochratoxin producing A. tubingensis isolates dominated in the samples.

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Kinetics of ochratoxin A production was examined in a number of ochratoxin producing isolates representing different sections of the Aspergillus genus. Both weak and high ochratoxin producers were tested using immunochemical or high-performance liquid chromatograhic methods. All isolates were found to produce the highest amounts of ochratoxin A after 7-10 days of incubation. Ochratoxin production varied between 30 - 5×105 ng ml-1 among the Aspergillus isolates tested. The A. albertensis and A. melleus isolates examined were found to produce ochratoxin A constitutively. A. albertensis produced the highest amounts of ochratoxin A at 30 °C after 7 days' incubation in YES liquid medium. Ergosterol content and ochratoxin production of A. albertensis cultures were in good correlation.

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Acta Alimentaria
Authors: J. Varga, R. Kiss, T. Mátrai, T. Mátrai, and J. Téren

Ochratoxin A is a mycotoxin produced by Aspergillus and Penicillium species. This mycotoxin is a common contaminant of various food products including cereal products, spices, dried fruits, coffee, beer and wine. Besides cereal products, beer and wine contribute significantly to ochratoxin exposure of humans. We examined the ochratoxin content of Hungarian wines and beers using an immunochemical technique. The detection limit of this technique is 0.01mg l-1. Altogether 65 wine and 25 beer samples were analysed. The presence of ochratoxin A was confirmed by HPLC in positive samples. Ochratoxin A was detected in 97.7% of wines, with ochratoxin concentrations ranging from 0 to 0.533mg l-1. The mean ochratoxin A concentration in wines was 0.110mg l-1. Only one of the Hungarian wines examined contained more than 0.5mg l-1ochratoxin A, the previously suggested EU limit for wine. Our data indicate that red wines are more frequently contaminated, and have higher mean ochratoxin contamination (0.117mg ml-1) than white wines (0.0967mg ml-1), in accordance with previous observations. A North-South gradient in wine ochratoxin concentrations is not evident from our data. For beers, all but one of the samples was found to be contaminated with small amounts of ochratoxin A with a mean concentration of 0.127mg l-1(range: 0.030-0.250mg l-1). Only one of the beers contained ochratoxin A above 0.2mg l-1, the anticipated European Community maximum allowable limit in beer. We could not detect correlation between the type and origin of beer and ochratoxin contamination.

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We examined the blastogenic response to phytohaemaglutinin (PHA) in HLA-B8, DR3 positive and negative subjects in the presence or absence of the immunosuppressive Fusarium mycotoxin.  HLA-B8, DR3 haplotype was associated with a depression of the response to mitogen in the absence of the mycotoxin, whereas in the presence of deoxynivalenol we could not detect significant differences among individuals either possessing or lacking this haplotype.

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Acta Alimentaria
Authors: J. Varga, Z. Koncz, S. Kocsubé, T. Mátrai, J. Téren, V. Ostry, J. Skarkova, J. Ruprich, A. Kubatova, and Z. Kozakiewicz

Ochratoxin A is a mycotoxin produced by Aspergillus and Penicillium species. This mycotoxin is a common contaminant of various foods including cereal products, spices, dried vine fruits, coffee, cocoa, beer and wine. Apart from cereal products, beer and wine contribute significantly to ochratoxin exposure of humans. In the Mediterranean region of Europe, the black Aspergillus species are the sources of ochratoxin contamination of grape products. In this study, we examined the source of ochratoxin contamination of grapes in Hungary and the Czech Republic. The mycobiota of grape berries from 25 Hungarian and Czech vineyards was examined. Potential ochratoxin producing fungi were only identified in grapes from Southern Hungary. Among the 16 black Aspergillus strains isolated, 12 belong to the A. niger species, and 10 produced small amounts (1.5–10 μg kg −1 ) of ochratoxin A in a liquid medium. We could also identify an A. tubingensis isolate which produced 3.5 μg kg −1 ochratoxin A in a liquid medium at pH 6.0. However, the amount of ochratoxin A produced was very low even in a medium which is favourable for mycotoxin production, and ochratoxin A was not detected in any of the grape juice, must and wine samples examined, indicating the absence of health hazard to costumers. Other potentially toxigenic fungi including Aspergillus flavus, Penicillium expansum and Alternaria species were also isolated. Further studies are in progress to evaluate the importance of these fungi in food safety.

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Acta Agronomica Hungarica
Authors: B. Tóth, O. Török, É. Kótai, M. Varga, É. Toldiné Tóth, X. Pálfi, E. Háfra, J. Varga, J. Téren, and Á. Mesterházy

Aspergillus and Penicillium species and their mycotoxins, including aflatoxins, ochratoxins, fumonisins and patulin, are frequently encountered on cereal products. The occurrence of these species and their mycotoxins on maize was investigated in Hungary after harvest in two consecutive years. Surface-sterilized cereal seeds were placed on selective media, and the isolated fungal strains were identified using morphological methods. In 2010 and 2011, 81.94% and 14.33%, respectively, of the samples were found to be contaminated with potentially toxigenic isolates. The species identification of selected isolates was carried out using sequence-based methods. Several Aspergillus flavus isolates were identified, which are potential aflatoxin producers. Other mycotoxinproducing species were also isolated, including black Aspergilli, which potentially produce ochratoxins and fumonisins, and A. clavatus, which produces patulin. In 2010 a large number of Penicillium species occurred in the samples, producing a wide range of mycotoxins. The mycotoxin content of the samples was analysed using the ELISA and HPLC techniques. Aflatoxins were not detected in any of the samples, while ochratoxins and fumonisins were successfully identified in some of the maize seeds.

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