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In this study, contamination by microscopic fungi (focused on Penicillium and Aspergillus species) of 75 fruit samples (strawberries, blackberries, blueberries, raspberries, grapes) and 29 tomato samples, which were obtained from Slovak stores was investigated. Totally 93.3% of fruit samples were contaminated with micromycetes (70.6% Botrytis spp., 52.0% Cladosporium spp., 42.7% Penicillium spp., 13.3% Rhizopus spp., 8.0% Alternaria spp., 6.7% Mucor spp., 5.3% Aspergillus spp., 4.0% Fusarium spp., and 1.3% Epicoccum spp.) and 6.7% of samples were contaminated with yeasts. The presence of 15 species of the genus Penicillium in fruits, namely P. atramentosum, P. aurantiogriseum, P. brevicompactum, P. bialowiezense, P. citrinum, P. crustosum, P. digitatum, P. expansum, P. fellutanum, P. glabrum, P. hordei, P. italicum, P. kiamense, P. olsonii, and P. purpurescens was found. With the highest frequency, P. brevicompactum (12.0%) and P. expansum (10.7%) were isolated from fruits. Four isolates of the genus Aspergillus were isolated from fruit samples (A. section Clavati, A. section Flavi, and two isolates of A. section Nigri). Thin layer chromatography (TLC) was used for testing of mycotoxin production by selected fungal isolates. Overall, 93.3% of tested Penicillium isolates and one tested Aspergillus of section Clavati proved the ability to produce at least one of the tested mycotoxins. As for tomato samples, 93.1% were contaminated with microscopic filamentous fungi (79.3% Penicillium spp., 24.1% Botrytis spp. and Alternaria spp., 10.3% Cladosporium spp., Mucor spp. and Rhizopus spp., 6.9% Aspergillus spp. and 3.4% Fusarium spp.) and 6.9% samples were contaminated with yeasts. In 65.5% of tomato samples, the occurrence of 8 species of the genus Penicillium (P. brevicompactum, P. crustosum, P. expansum, P. griseofulvum, P. italicum, P. olsonii, P. sublectaticum, P. thomii), and two species of the genus Aspergillus (from section Circumdati and Flavi) was recorded. P. olsonii (58.6%) and P. griseofulvum (10.3%) were isolated with the highest frequency. All 7 tested Penicillium isolates (100.0%) and 1 isolate of the genus Aspergillus (section Flavi), which were obtained from tomatoes, had the ability to produce at least one of the tested mycotoxins. Aspergillus section Flavi isolate (from tomatoes of Slovak origin) produced 5.5 μg.mL-1 of aflatoxin B1, 4.2 μg.mL-1 of aflatoxin B2, 154.4 μg.mL-1 of aflatoxin G1, and 5.6 μg.mL-1 of aflatoxin G2 on 14th day of cultivation on liquid YES medium at 25±1 °C in darkness, and detected by high pressure liquid chromatography (HPLC). [ABSTRACT FROM AUTHOR]

Vegetables represent a very important part of the diet. However, one of the problems of the vegetable market is its shelf life and related safety. A significant reason for vegetable losses in the retail network is the development of microorganisms, mainly micromycetes. They can significantly affect the quality of products, and due to the production of toxic metabolites, they also carry a toxicological risk. The aim of our study was to detect fungi that cause damage to selected types of vegetables in the food retail chains in Slovakia and are therefore directly responsible for product losses. Totally 44 samples of root, cabbage, and fruiting vegetables were mycologically analysed. Micromycetes, causing visible damage to the analysed vegetable samples, were inoculated to M137, M096, or M696 media from HiMedia and cultivated for 7 days at 25±1 °C. Important isolates were subjected to toxicological analysis by the thin-layer chromatography. The results show that the most common cause of carrot spoilage is the genus Berkeleyomyces. In the case of parsley, it was yeast Geotrichum candidum. Alternaria spp. occurred most often in the case of broccoli and cauliflower. Tomatoes were the most frequently spoiled by representatives of the genus Penicillium, or Botrytis cinerea and Cladosporium, cucumbers by Cladosporium and Alternaria species, similar to peppers, and the main spoiler of eggplants was Botrytis cinerea. Alternaria spp. showed a relatively high ability to produce altenuene, alternariol, and alternariol monomethyl ether. Penicillium expansum from carrots produced roquefortine C, patulin, and citrinin, and Penicillium paneum from tomatoes synthesized roquefortine C. [ABSTRACT FROM AUTHOR]