Antifungal activities of essential oils from Southern African medicinal plants against five Fusarium species

Abstract

In the present study, essential oils from 9 plants traditionally used to treat infectious diseases were tested against five Fusarium spp. using the agar diffusion method. The minimum inhibitory concentrations (MIC) of the oils were determined by the microdilution technique. The killing kinetics of the oils was further evaluated against the fungal organisms. Antifungal activity was exhibited by essential oils from Conyza scabrida, Eriocephallus panculatus, Artemesia afra, Pelargonium graveolons and Mentha peripeta with 100% growth inhibition against all the five Fusarium spp with the zone of inhibition ranging from 10 to 18 mm. The essential oils of C. scabrida and M. piperita were fungicidal to four of the five fungal species tested with minimum fungicidal concentration (MFC) values ranging from 0.95 to 7.50 mg/ml. All the essential oils tested were able to kill the cells at different rates varying from 48 to 100% after 2 days of experimentation. The results of the present study indicate that essential oils tested are promising sources of natural products with which could be used for the control of Fusariuminfections. These results will guide the selection of some plant species for further pharmacological and phytochemical analysis. These results also support the traditional use of these essential oils. Key words: Fusarium spp, anti-fungal activity, essential oils, fungi, Southern Africa, medicinal plants.