食品与工业微生物学杂志

Morphologic and Molecular Characterization of Aspergillus flavus Isolated from Smoked, Fermented and Dried Fishes Sold in Main Markets of Cotonou (Benin)

Abstract

Yann Christie S Adjovi, Gerard Hodeve Tiko, Benoit G Gnonlonfin and Ambaliou Sanni

Fungal infection and aflatoxin contamination were evaluated on smoked or dried fishes sold in surrounding markets of Cotonou. These fishes are traditionally processed to avoid losses and rapid perishability and preserve them from a longer period. Fungal contamination was evaluated after plating on selective media with a total of 175 fungal isolated from 56 samples. Fungi identification shown high prevalence of Aspergillus genus that represent 44, 56% followed by Mucors (30%), Rhizopus and Rhizomucor (9.14%; 5.14%, respectively), Penicillum sp. (6.85%) and another minority. In Aspergillus genus, A. flavus represented 29.48% after A. niger that was 37.17%. A. parasiticus, A. fumigatus, A. wentii, A.clavatus and A. ochraceus had 10.25%, 7.69%, 5.12%, 3.84% and 2.56% respectively followed by A. tamarii, A. candidus and A. versicolor that had 1.28% each. In aflatoxin pathway gene cluster, we investigated three specific genes AflD, AflO and AflP to 18 stumps of A. flavus isolated. This shows that there are potential aflatoxins producers which were suspected by their fluorescence on CCA medium at visible UV and confirmed by determination in chloroformic extract by HPLC. TLC results of chloroformic extracts of samples confirmed the presence of AFB1 in some samples. This is the first study that shows mycotoxigenic fungi and mycotoxins in traditionally processed fishes sampled from Cotonou markets in Benin.