Chemical composition of essential oils from leaf and bud of clove and their impact on the antifungal and mycotoxin inhibitory activities of clove oil-in-water nanoemulsions

Abstract

The impacts of clove oil (CO) type on the physicochemical properties, antifungal activities, and mycotoxin inhibitory efficacies of CO-in-water nanoemulsions were investigated. By blending 25 wt% of clove oil with 75 wt% of corn oil in oil phase (5 wt%), clove bud oil (CBO)-in-water nanoemulsion and clove leaf oil (CLO)-in-water nanoemulsion showed highly physical stable with the mean particle size < 170 nm. The concentration of major chemical constituents such as eugenol and caryophyllene in nanoemulsion maintained constant during storage time. The antifungal activities of nanoemulsions against two Fusarium graminearum isolates were strongly dependent on the CO concentration. For instance, CLO nanoemulsion displayed an appreciable higher antifungal activity compared to CBO nanoemulsion at a lower CO concentration. Both nanoemulsions could effectively inhibit fungal mycelial growth and spore germination , but in a different antifungal mode of actions. Regarding the mycotoxin inhibitory efficacy, both CO nanoemulsions could effectively inhibit mycotoxin production including deoxynivalenol (DON) and its derivatives: 3-acetyl-deoxynivalenol (3ADON), 15-acetyl-deoxynivalenol (15ADON). • Chemical composition of clove bud oil (CBO) and clove leaf oil (CLO) showed differences. • The physicochemical stability of clove oil (CO)n nanoemulsions were fabricated. • Antifungal activity of CO nanoemulsions was in a dose-dependent manner. • Different antifungal modes of actions between CBO and CLO was observed. • Both CO nanoemulsions could effectively inhibit mycotoxin production.