A new hydrogel containing a proanthocyanidin polymer-rich extract of Commiphora leptophloeos for treating vulvovaginal candidiasis: Preclinical results using the alternative model of Galleria mellonella

In the present study, we aimed to develop and characterize a hydrogel formulation containing a proanthocya-nidin polymer-rich extract of Commiphora leptophloeos and investigate its toxicity and antifungal effect in vitro and in vivo on Galleria mellonella infected with Candida albicans larvae. The extract (4%) was incorporated into a hydrogel formulation based on chitosan (1.0%) and poloxamer 407 (18%), and evaluated by physical (organ-oleptic characteristics, rheological tests, and texture profile analysis), chemical (proanthocyanidin content and pH), and microbiological parameters. Under the study conditions, the new hydrogel displayed good physico-chemical and microbiological stability for 3 months at 25 degrees C. Both the extract and the hydrogel were evaluated regarding their safety and efficacy in vitro on uterine/endometrial epithelial cells (HEC-1A) and against Candida spp. strains, as well as in vivo in the alternative model of acute toxicity and C. albicans-infection in G. mellonella. The results showed that the hydrogel is biocompatible with the vaginal environment, becoming more viscous with increasing temperature, and has higher antifungal potential compared to a free extract at all tested con-centrations in vitro (2172-33.9 & mu;g/mL), and in vivo at the dose of 125 mg/kg. Overall, the data provide evidence of the potential of the new hydrogel to be applied in treating vulvovaginal candidiasis.