In vivo antifungal activity of nanoemulsions containing eucalyptus or lemongrass essential oils in murine model of vulvovaginal candidiasis

The objective of this study was to evaluate the antifungal activity of eucalyptus (Eucalyptus globulus) and lemongrass (Cymbopogon flexuosus) essential oils in their free and nanoemulsion forms in the murine model of vulvovaginal candidiasis (VVC). The nanoemulsions were developed by the homogenization method under high agitation and characterized according to the mean droplet size, polydispersity index, zeta potential, and pH. The murine VVC model was induced in BALB/c mice by the administration of estradiol valerate preceding the Candida albicans challenge. Nanoemulsions containing eucalyptus or lemongrass oils showed average droplet size of less than 100 nm, a polydispersity index about 0.2, negative zeta potential, and acidic pH. For in vivo treatment of VVC, the essential oils in their free form did not show antifungal activity, while the two nanoemulsions were able to reduce the fungal load similarly or better than the control animal group treated with miconazole cream. The results obtained in this study demonstrated that the use of nanoemulsions containing eucalyptus or lemongrass essential oils could be a promising alternative to be used as a proof of concept to develop a new therapy for the treatment of VVC.