Inhibition of fungal development in maize grains under storage condition by essential oils

The ability of the essential oils from Lippia rugosa and Plectranthus glandulosus to inhibit the fungal infection in corn under storage condition was assessed. The mycelia growth inhibitory activity of L. rugosa and P. glandulosus essential oils against Aspergillus flavus, Aspergillus niger, Aspergillus parasiticus and Fusarium moniliforme was firstly determined on potato dextrose agar. Maize samples were distributed among boxes, inoculated with 2 ml (106 spores/ml) of conidia suspension of these strains, treated with essential oil and stored for 30 days. L. rugosa exhibited the lowest MIC value in liquid medium ranged from 0.2 to 0.5 mg/ml against all fungal strain, and P. glandulosus which was less active with value ranged from 0.8 to 1.6 mg/ml against all fungal strain. Under storage condition in corn, fungal contamination reductions from 63 to 97% by L. rugosa and from 27.3 to 70% by P. glandulosus against all fungal strain after 15 days of conservation were recorded with 6μL/g grain. These results suggest that the essential oils from Lippia rugosa and Plectranthus glandulosus may be used in grain storage against fungi responsible for biodeterioration.