Unveiling combat strategies against Candida spp. biofilm structures: Demonstration of photodynamic inactivation with innovative phthalocyanine derivatives

Abstract

Antimicrobial resistance is an important problem for infection control and therapy. Microorganisms in biofilm structure are remarkably less susceptible to antimicrobials compared to planktonic cells. Increasing rates of resistance to antimicrobials have led to the development of new antimicrobial strategies. Antimicrobial photodynamic therapy (PDT) is an alternative treatment method that may contribute to the fields of infection control and treatment. This study aimed to investigate the antifungal activities of photosensitizers and the anti-biofilm activities of phthalocyanine derivatives on C. albicans and C. parapsilosis strains. The anti-biofilm effects of aPDT on the biofilm of Candida albicans were also visualized via SEM (Scanning Electron Microscopy). Our findings showed that aPDT with phthalocyanines inhibited biofilm production levels and reduced the mature biofilm levels of Candida strains. Additionally, SEM results supported that aPDT application successfully eradicated fungal cells and inhibited the biofilm produced by C. albicans. Although more detailed experiments are needed, we suggest that the use of Pcs in aPDT may be beneficial for the treatment of biofilm-related Candida infections.