The presence of Aspergillus section Flavi and aflatoxin (AF) contamination was investigated in 112 samples of peanuts, almonds and dried figs collected in Algeria. The occurrence of aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) in different commodities has been determined with a sensitive method based on high performance liquid chromatography (HPLC) coupled with fluorescence detection with post-column photochemical derivatisation. Analytical results indicated that 28 samples of peanuts, 16 samples of almonds and 26 samples of dried figs contained detectable levels of AFs. A total of 69 samples (61.6%) were contaminated with AFB1 ranging from the limit of quantification to 174 µg kg. AFB2 was found in 12 samples (10.7%) and varied from 0.18 to 193 µg kg. Seven samples revealed AF concentrations lower than the limit of quantification. Eleven peanut and fourteen dried fig samples exceeded the European maximum limits for AFB1.

This work reports the occurrence of the fungal flora and evaluates the mycotoxigenic potential of Aspergillus genera in 63 samples of oil seeds and nuts (almonds, pistachio and sesame seeds). Fungal isolation and identification revealed the presence of 5 genera (Aspergillus, Penicillium, Cladosporium, Mucor and yeasts) with the predominance of Aspergillus section Nigri. A number of 138 strains of Aspergillus section Nigri and 91 of Aspergillus section Flavi were isolated and tested for their ability to produce ochratoxin A (OTA) and Aflatoxin, respectively. The detection of Aflatoxins and OTA production was carried out using thin-layer chromatography (TLC). Our results showed that 93.93% of Aspergillus carbonarius were able to produce OTA, but none of the Aspergillus niger aggregate was found to be an OTA-producer. Among the 91 Aspergillus section Flavi isolates, 88 were identified as Aspergillus flavus and 3 as Aspergillus parasiticus. All A. parasiticus were strong AFB and AFG producers. A percentage of 30.3% of A. flavus isolates produced AFB1, with levels ranging from 0.69 to 44.28 μg.g−1. The frequency of aflatoxigenic A. flavus strains was higher in pistachios (46.3%) than in almonds (30.3%) or sesame seeds (23.52%). Cyclopiazonic acid (CPA) and sclerotia production were carried out on CYA medium. All aflatoxigenic A. flavus strains produced CPA, whereas 29.2% produced sclerotia (L-type).

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