Fatty acid esters of fumonisins: first evidence of their presence in maize

Fumonisin derivatives obtained by esterification of fumonisin B-1 (FB1) with palmitic, oleic and linoleic fatty acids have been recently described, but never reported in raw maize so far. In this study, the presence of oleoyl-EFB1 (EFB(1)OA) and linoleoyl-EFB1 (EFB(1)LA) in raw maize is reported by means of a suitable LC-ESI-MS/MS method. In addition, the production of EFB1 derivatives by three Fusarium verticillioides strains is described on malt extract-based media and on corn meal-based growth media. EFB(1)OA and EFB(1)LA were produced by all considered strains in corn meal medium, with EFB(1)LA>EFB(1)OA. On the contrary, EFB(1)OA and EFB(1)LA were never observed in Fusarium cultures grown on a malt extract medium, suggesting that the esterification of FB1 can occur only in a complex matrix such as maize.