Antifungal and antimycotoxigenic effects ofZingiber officinale, Cinnamomum zeylanicumandCymbopogon martiniiessential oils againstFusarium verticillioides

There is an increasing demand for fungi control in grains, especially toxigenic. Also, there is growing concern on the use of synthetic fungicides; thus alternatives are needed. The aim of this study was to evaluate the antifungal and antimycotoxigenic action of essential oils (EOs) fromZingiber officinale, Cinnamomum zeylanicumandCymbopogon martiniiagainstFusarium verticillioides, a spoilage and toxigenic fungus. Essential oils were first chemically characterised by gas chromatography coupled to mass spectrometry, and their antioxidant potential was measured by the DPPH, ABTS and FRAP methods. Minimum inhibitory concentration (MIC) and disc diffusion were used to assess antifungal activity. Scanning electron microscopy was used to evaluate morphological changes in the fungus. Antimycotoxigenic activity of the EOs against the production of fumonisin B(1)and B(2)byF. verticillioideswas evaluated using ultra-high-performance liquid chromatography system.Z. officinale, C. zeylanicumandC. martiniiEOs were predominantly composed by zingiberene and geranial; eugenol; and geraniol, respectively. All the EOs had high antioxidant power, especially that fromC. zeylanicum. The MICs were 250, 500 and 2,000 mu g mL(-1)forC. zeylanicum, C. martiniiandZ. officinaleEOs, respectively. Mycelial reduction ofF. verticillioideswas observed when EOs were used, and the lowest activity was detected in theZ. officinaleEO. Overall, the tested EOs promoted structural damage to the fungal cell wall, decreased conidia size and mycelial reduction. Antimycotoxigenic evaluation of the EOs evidenced a significant reduction (p< .05) in the production of fumonisins B(1)and B(2)with all the EOs evaluated in the study. These results suggest that especiallyC. zeylanicumandC. martiniiEOs are highly useful for controllingF. verticillioidesand fumonisins production.