Control of fumonisin B 1 accumulation in naturally contaminated maize inoculated with Fusarium verticillioides and Fusarium proliferatum, by cinnamon, clove, lemongrass, oregano and palmarosa essential oils

The effect of cinnamon, clove, oregano, palmarosa and lemongrass oils on fumonisin B₁ (FB₁) accumulation by one isolate each of Fusarium verticillioides and Fusarium proliferatum in non-sterilised naturally contaminated maize grain at 0.995 and 0.950 a_w and at 20 and 30 °C was evaluated. The concentration used was 500 mg kg^-1 maize. Under these conditions it was shown that antimycotoxigenic ability only took place at the higher water availabilities, and mostly at 20 °C. Only cinnamon, lemongrass and palmarosa oils were somewhat effective. Moreover, it was suggested that competing mycoflora plays an important role in FB₁ accumulation. It was concluded that the efficacy of essential oils in real substrates, such as cereals, may be much lower than in synthetic media; different essential oils may be found to be useful and at different concentrations. Their effectiveness is highly dependent on both abiotic and biotic factors involved.