Conference Paper

MYCOMON -nine years the study duration (1999-2007)

Conference: 30. Mycotoxin Workshop, At Utrecht, The Netherlands

ABSTRACT Introduction:
Toxigenic microfungi are microorganisms capable of producing mycotoxins. They are important factors that may have a potentially negative effect on human health. The most important toxigenic microfungi are the producers of aflatoxins and ochratoxin A. Foodstuffs are suitable substrates for the contamination, growth and propagation of toxigenic microfungi and for the production of mycotoxins. A study „MYCOMON” of the occurrence of toxigenic microfungi, producers of aflatoxins and ochratoxin A, in selected commodities of a consumer food basket was prepared. Investigations in this study were incorporated into the National Environment Health Monitoring Programme in the Czech Republic. Its objective was to obtain information on the degree of the immediate contamination of foodstuffs with toxigenic microfungi which could serve as the basis for the evaluation of the dietary exposure and health risk assesment of afla- and ochra- toxigenic microfungi in the Czech foodstuffs.
Materials and Methods:
Twenty-five commodities were purchased from retail at 12 places in 4 terms (March, May, September, November) during the years 1999–2007. It presents 2196 foodstuffs samples in all. Aflatoxigenic microfungi Aspergillus Section Flavi (e.g. Aspergillus flavus, Aspergillus parasiticus) and ochratoxigenic microfungi (Aspergillus ochraceus, Aspergillus Section Nigri, Penicillium verrucosum, Penicillium nordicum) were monitored in foodstuffs. CSN ISO 7954 norm and classical mycological methods were used. Chromogenic media (AFPA medium, ADMB medium, DRYES agar and PRYES agar) were used for identification of toxigenic microfungi. Chemotaxonomy, HPTLC determination of aflatoxins and cyclopiazonic acid in YES medium was carried out.
Results and Conclusions:
Frequency data about the quantitative incidence of microfungi, qualitative and quantitative incidence of toxigenic microfungi for these commodities were obtained. CFU/g and the mycological profile of selected toxigenic microfungi were assessed. 115 (63% toxigenic) strains of Aspergillus flavus were isolated from foodstuffs (black tea, fruit tea, caraway seeds, fine semolina, fine flour, granular flour, semi-granular flour, sweet red pepper, black pepper, raisins, rice, pasta, oat flakes), 26 (46% toxigenic) strains of Aspergillus tamarii were isolated from foodstuffs (black tea, black pepper, sweet red pepper) and 254 strains of Aspergillus Section Nigri were isolated from foodstuffs (black tea, fruit tea, caraway seeds, peanuts, fine flour, sweet red pepper, black pepper, raisins, rice, fine flour, fine semolina). A. parasiticus, A. nomius A. ochraceus, Penicillium verrucosum, Penicillium nordicum were not isolated from the tested foodstuffs. The toxigenic microfungi are stored in 30 % solution of glycerol in deep-freezer box by – 71 oC for further research.
This study was supported by the Czech National Environment and Health Monitoring Programme

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Available from: Vladimir Ostry, Jun 30, 2015
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