Antifungal Activity of Punica granatum L. Peel Extract and Chitosan Nanoparticle-Coated Formulation Against Candida...

Increasing incidence of candidiasis and emergence of antifungal resistance necessitate the development of alternative antifungal strategies. In this context, the antifungal activity of the crude extract of Punica granatum L. peel (PGPE) and its chitosan nanoparticle-coated formulation (PGPE-CSNPs) was investigated against Candida albicans (ATCC 10231), Candida glabrata (ATCC 66032), Candida kefyr (ATCC 46764), Candida parapsilosis (ATCC 22019), and Candida tropicalis (ATCC 13803). Although the individual antimicrobial activities of PGPE and CSNPs have been investigated, their combined application against Candida spp. remains unexplored in the literature. The antifungal efficacy was evaluated using agar well diffusion, disk diffusion, minimum inhibitory concentration (MIC), and minimum fungicidal concentration (MFC) testing, and compared with fluconazole and amphotericin B. The morphological characterization of PGPE-CSNPs was performed using scanning electron microscopy (SEM), which confirmed successful encapsulation and revealed a smoother surface with uniformly distributed nanometric pore structures and reduced aggregation compared to uncoated CSNPs. PGPE-CSNPs showed greater inhibition zones than amphotericin B, except against C. albicans. The CSNPs formulation reduced the MIC from 8 µg/mL to 4 µg/mL and the MFC from 16 µg/mL to 8 µg/mL, representing a two-fold enhancement against C. albicans. No enhancement in activity was observed against C. glabrata, whereas for C. kefyr, only MFC values decreased from 8 µg/mL to 4 µg/mL. For both C. parapsilosis and C. tropicalis, MIC values reduced from 16 µg/mL to 8 µg/mL, and MFC values reduced from 32 µg/mL to 16 µg/mL for both species. PGPE-CSNPs exhibited significantly lower MIC and MFC values than the crude extract alone (p < 0.05). These findings suggest that chitosan-based nanocarriers may enhance the antifungal efficacy of plant-derived bioactive compounds, highlighting their potential as a promising alternative antifungal strategy, a combinatorial approach not previously reported in the literature.