Enhanced antibiofilm and antifungal activities of a hexanophenone nanoformulation against Candida albicans: a...

Biofilm-associated antifungal resistance in Candida albicans requires urgent attention for the development of novel and more effective therapeutics. Herein, the development of a nanosuspension (HP-NS) of a bioactive natural compound, hexanophenone (HP), with enhanced antifungal efficacy is reported. The average diameter of nanoparticles was found to be 14.85 ± 3.05 nm. The HP-NS exhibited significantly enhanced antifungal and antibiofilm efficacies compared to native HP. Notably, a significant reduction of ∼78% and ∼73% was observed in MIC₉₀ and MIC₅₀, respectively, while MBIC₉₀ and MBIC₅₀ values showed reductions of ∼56% and ∼76%, respectively. Also, the qualitative agar well diffusion assay displayed a distinct zone of inhibition for HP-NS, whereas the free compound showed negligible activity, indicating improved bioavailability and interaction with fungal cells. The plasma membrane fluorescence anisotropy studies displayed gradual fungal membrane disruption with increasing concentrations of HP-NS, highlighting mechanistic insight into its enhanced antifungal efficacy. Additionally, the increased generation of intracellular reactive oxygen species (ROS) in C. albicans following treatment with HP-NS suggests oxidative stress-mediated fungal cell damage as a contributing mechanism. Furthermore, percent cell viability was evaluated using the MTT assay on HCT-116 cells, which demonstrated dose-dependent effects, with IC₅₀ values of 218 ± 4 µg mL^-1 and 157 ± 2 µg mL^-1 when treated with HP-NS and HP, respectively. The nanoscale size of HP-NS contributes to its improved physico-chemical properties, particularly increased surface area, which likely accounts for its superior antifungal performance. These findings highlight the potential of nanosuspension formation as an effective method to overcome the fundamental limitations of natural antifungal agents, particularly against biofilm-forming pathogens. This work presents HP-NS as a promising antifungal agent and provides valuable insights into the application of nanotechnology for enhancing the efficacy of natural bioactive compounds.