Antifungal and Antibiofilm Activities of Ozonated Sunflower Oil against Candida albicans Strains: A Pilot Study and Clinical Perspectives

Abstract

Aims: This study aimed to assess the antifungal and antibiofilm activities of ozonized (OGOZ) and non-ozonized (OG) Helianthus annuus (sunflower) oil against Candida albicans strains. Study Design: Laboratory-based study. Place and Duration of Study: Microbiology Laboratory of the Federal University of Ceará and State University of Vale do Acaraú, from August 2023 to Decembrer of the same year. Methodology: Seven clinical strains and one reference strain (ATCC 90028) were examined. Initially, antimicrobial susceptibility testing (AST) was performed using a modified disk diffusion method with both OGOZ and OG. Strains that displayed sensitivity were then subjected to a broth microdilution assay to determine the Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC). The biofilm assay was conducted specifically with the C. albicans reference strain. Results: AST results showed that all strains exhibited inhibition zones with OGOZ, while non-ozonized oil did not produce inhibition zones. MIC values ranged from 0.15 to 2.50 mg/mL, with one clinical strain (LABMIC H10) demonstrating an MIC value 16 times lower than other strains. None of the strains reached MFC at the tested concentrations. In terms of biofilm formation, application of MIC and twice the MIC resulted in a 48,6% and 85% reduction in mature biofilms, respectively. Conclusion: The findings indicate that OGOZ has fungistatic and antibiofilm effects, highlighting its potential as a promising agent for bioprospecting. Further clinical trials are essential to evaluate its therapeutic potential for managing infectious diseases such as oral candidiasis.