Chitosan hydrogel loaded with Chamaecyparis pisifera essential oil exhibits antifungal activity against clinically...

New therapeutic approaches are needed to control infections caused by Candida, and encapsulating bioactive substances has attracted increasing interest as a promising strategy. In this study, a chitosan-based hydrogel containing Chamaecyparis pisifera essential oil (HCP) was formulated and evaluated for antifungal activity, physicochemical characterisation and toxicity assessment.

The chemical composition of the essential oil was analysed by gas chromatography coupled to a flame ionization detector (GC-FID) and mass spectrometry (GC-MS), identifying α-pinene (30.21%) and bornyl acetate (24.42%) as the major constituents. The formulation showed particle sizes ranging from 252 to 839 nm and remained physically stable for up to 150 days. The antifungal activity of HCP was evaluated against clinical isolates of Candida spp., with minimum inhibitory concentration (MIC) values ranging from 150 to 0.01 μg mL⁻¹ for Nakaseomyces glabratus (formerly C. glabrata) and Meyerozyma guilliermondii (formerly C. guilliermondii), respectively. Thermal analyses demonstrated favorable thermal properties of the hydrogel, and electron microscopy confirmed a porous structure and incorporation of the essential oil into the chitosan matrix. Rheological analysis indicated non-Newtonian pseudoplastic behaviour. Furthermore, the hydrogel showed an acceptable safety profile, being non-irritant and presenting no toxicity towards blood cells or Galleria mellonella.

Taken together, these findings demonstrate that the HCP hydrogel exhibits antifungal activity against clinically relevant Candida spp. and represents a potential antifungal biomaterial for future therapeutic applications.