ABSTRACT Molds are a group of microorganisms responsible for food spoilage. Their presence is highly linked to the synthesis of toxic substances (mycotoxins) which are responsible for considerable economic losses due to the rejection of contaminated batches, as well as myriad of serious risks to human and animal health. In this study, samples of food commodities including tea leaves of different brands and dried fruits (peanuts, walnuts, raisins, pistachios and figs) were collected from different Moroccan areas to isolate and identify potential aflatoxin fungi. Interestingly, results showed that Aspergillus (A. flavus and A. niger) was the dominant genus represented by 42 strains (66.7%), with an abundance of 26.1, 23.8, 19, 14.2, 11.9 and 2.3% in tea, peanuts, figs, nuts, raisins and pistachios, respectively. The second genus Penicillium, represented by 18 strains (28.5%), was isolated in variable proportions of 38.9, 33.3, 16.7, 5.6 and 5.6, respectively for fig, raisins, peanuts, dates and walnuts samples. Analysis of the isolated mold cultures by thin-layer chromatography (TLC) indicated that out of 30 total strains, 13 (43.3%) were aflatoxinogenic and able to produce type B aflatoxin. The cytotoxicity test (LC50) of isolated fungal strains on Artemia salina larvae showed that species from the two genera remain the most toxigenic, with mortality rates ranging from 70% to 100%. Biocontrol of the fungal growth with tested lactic acid bacteria strains showed a significant inhibitory effect against Penicillium sp. and A. niger compared to the control assay.
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