Mycotoxins: Fungal secondary metabolites with toxic properties
Résumé
Fungi are frequent contaminant of foodstuffs worldwide. According to environmental conditions and their own physiological particularities, they can develop on living plants in the fi eld or during pre-harvest period as well as during storage in case of drying failure or re-moistening. During their evolution, the fi lamentous fungi have become one of the most important sources of secondary metabolites. Many of these secondary metabolites display properties interesting for pharmaceutical or food industry. But other metabolites, named mycotoxins, have several detriment effects on both human and animals. The variety of biological activities of fungal secondary metabolites is directly related to the large diversity of these metabolites in terms of chemical structures. This chemodiversity is largely due to the variety of not only “backbone” enzymes like polyketide synthases (PKS), isoprenyl disphosphate synthases, non ribosomal peptide synthetases (NRPS) and dimethylallyltryptophane synthases (DMATS) but also the tailoring enzymes involved in their biosynthesis. Mycotoxins can thus be classifi ed into four main categories: polyketides, terpenes, non ribosomal peptides and hybrids.