Development and in Vitro Assessment of Cumin Essential Oil Nanoemulsion and Nanoemulgel Formulations for Vaginal Candidiasis

Abstract

Vaginal candidiasis is a common mucosal infection caused by various Candida species, primarily Candida albicans. Increased drug resistance to current antifungal treatments, high recurrence rates, and local side effects necessitate the development of new and effective carrier systems. This study aimed to optimize nanoemulsions containing cumin (Cuminum cyminum) essential oil using a Taguchi Design of Experiments and to convert them into nanoemulgel dosage forms using alginate and carboxymethyl cellulose for the treatment of vaginal candidiasis. The chemical composition of cumin essential oil was determined by GC-FID/MS. Optimization of the nanoemulsions was carried out by targeting droplet size and polydispersity index. The nanoemulsions were additionally characterized by determining zeta potential, pH, and conductivity, and their physical stability was assessed over 30 days. The rheological behavior, spreadability, and ex vivo bioadhesion properties were also investigated. The in vitro antifungal activities of the formulations against Candida species and their cytotoxicity profiles on Vero cells were evaluated. The results showed that the optimum nanoemulsion exhibited a mean droplet size of 11 nm, a low PdI value, and good physical stability. Nanoemulgels containing 1.5% carboxymethyl cellulose exhibited better spreadability, whereas nanoemulgels containing 4.5% alginate exhibited higher bioadhesion. The nanoemulsion and nanoemulgel formulations were effective against all Candida strains. The toxicity of the nanoemulsion and nanoemulgel formulations was significantly lower compared to free cumin essential oil (p < 0.001). In conclusion, the developed cumin essential oil-containing nanoemulsion and nanoemulgel formulations are considered promising and safe pharmaceutical candidates for the topical treatment of vaginal candidiasis.