Abstract
Malassezia is a fungal genus that is part of the skin's normal mycobiota but can also cause various diseases. The emergence of resistance to antimicrobial agents in several microorganisms, including Malassezia yeasts, has led to the exploration of new therapeutic alternatives such as antimicrobial peptides. This study aimed to investigate the effect of Satanin 1, a recently identified antimicrobial peptide, against Malassezia using broth microdilution assays, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM), and a Galleria mellonella infection model. Results showed that the Minimal Inhibitory Concentration (MIC) of Satanin 1 against Malassezia ranged from 50 to 12.5 µg/mL, and the peptide works by affecting the fungal cell surface. Nonetheless, Satanin 1 treatment did not improve the survival of infected G. mellonella, possibly due to an exacerbated immune response in the larvae, as shown by hemocyte population characterization and histopathological analyses. Continued investigation into alternative molecules, like antimicrobial peptides, is essential to combat the increasing threat of antifungal resistant microorganisms.