Antimicrobial Activity of the Peptide C14R Against Ab Initio Growing and Preformed Biofilms of Candida albicans, Candida parapsilosis and Candidozyma auris

Biofilms are the predominant lifeforms of microorganisms, contributing to over 80% of infections, including those caused by <i>Candida</i> species like <i>C. albicans</i>, <i>C. parapsilosis</i> and <i>Candidozyma auris</i>. These species form biofilms on medical devices, making infections challenging to treat, especially with the rise in drug-resistant strains. <i>Candida</i> infections, particularly hospital-acquired ones, are a significant health threat due to their resistance to antifungals and the risk of developing systemic infections (i.e., sepsis). We have previously shown that C14R reduces the viability of <i>C. albicans</i> and <i>C. auris</i>, but not of <i>C. parapsilosis</i>. Here, we show that C14R not only inhibits viability by pore formation, shown in a resazurin reduction assay, and in a <i>C. parapsilosis</i> and fluorescence-based permeabilization assay, but it also halts biofilm maturation and significantly reduces the biomass of preformed biofilms by over 70%. These findings suggest C14R could be an effective option for treating severe fungal infections, offering a potential new treatment approach for biofilm-related diseases. Further research is needed to fully understand its biofilm dispersal potential and to optimize its use for future applications as an antifungal in clinical settings.