Aflatoxigenic potential of Aspergillus section Flavi isolated from maize seeds, in Burkina Faso

The frequency of occurrence and four principal kinds of aflatoxin concentration in maize seeds grown in Burkina Faso was investigated. Ten (10) samples collected, were analyzed by high performance liquid chromatography (HPLC) with post-column derivatisation after immunoaffinity column cleanup. Eight strains of Aspergillus section Flavi were previously isolated from these samples and cultivated on “Aspergillus flavus and parasiticus agar (AFPA)” to ascertain if they belong to A. flavus or A. parasiticus species. The qualitative ability of aflatoxin production was also previously performed by fluorescence emission under ultra violet light at 365 nm after four (4) days of incubation at 30 °C on Coconut Agar Medium (CAM). Results showed that 70% of samples were contaminated by aflatoxins. The levels ranged from 0.93 to 58.94 µg/kg. Samples M1 and M10 had high concentrations, 58.94 µg/kg and 70.73 µg/kg; whereas M4 and M5 had low concentrations from 1.68 to 0.93 µg/kg, respectively. In these samples, four were contaminated with aflatoxin B1 (AFB1) and aflatoxin G1 (AFG1), two with AFB1 and aflatoxin B2 (AFB2) and one (01) with AFB1 only. We notice that AFB1 was the most prevalent member of aflatoxins, and AFG2 was absent in all samples.   Key words: Maize, Aspergillus, aflatoxins, HPLC, Burkina Faso.