Mycotoxin production by Fusarium species isolated from bananas

The ability of Fusarium species isolated from bananas to produce mycotoxins was studied with 66 isolates of the following species: F. semitectum var. majus (8 isolates), F. camptoceras (3 isolates), a Fusarium sp, (3 isolates), F. moniliforme (16 isolates), F. proliferatum (9 isolates), F. subglutinans (3 isolates), F. solani (3 isolates), F. oxysporum (5 isolates), F. graminearum (7 isolates), F. dimerum (3 isolates), F. acuminatum (3 isolates), and F. equiseti (3 isolates). All isolates were cultured on autoclaved corn grains, Their toxicity to Artemia salina L. larvae was examined. Some of the toxic effects observed arose from the production of known mycotoxins that were determined by thin-layer chromatography, gas chromatography, or high-performance liquid chromatography. All F. camptoceras and Fusarium sp. isolates proved toxic to A. salina larvae; however, no specific toxic metabolites could be identified. This was also the case with eight isolates off. moniliforme and three off. proliferatum. The following mycotoxins were encountered in the corn culture extracts: fumonisin B-1 (40 to 2,900 mu g/g), fumonisin B-2 (150 to 320 mu g/g), moniliformin (10 to 1,670 mu g/g), zearalenone (5 to 470 mu g/g), alpha-zearalenol (5 to 10 mu g/g), deoxynivalenol (8 to 35 mu g/g), 3-acetyldeoxynivalenol (5 to 10 mu g/g), neosolaniol (50 to 180 mu g/g), and T-2 tetraol (5 to 15 mu g/g). Based on the results, additional compounds produced by the fungal isolates may play prominent roles in the toxic effects on larvae observed. This is the first reported study on the mycotoxin-producing abilities of Fusarium species that contaminate bananas.