Logo do repositório

Percorrer por autor "Teixeira, Vitor"

A mostrar 1 - 1 de 1
  • Enhancing antifungal activity against Candida albicans using novel organic compounds
    Publication . Alves, Beatriz; Silva, Rui; Vieira, Mónica; Ferraz, Ricardo; Fernandes, Silvia; Teixeira, Vitor; Pereira, Clara; Almeida Vieira, Mónica Andreia; Fernandes, Sílvia
    Candida albicans is the predominant cause of inva-sive candidiasis, a major global health threat [1 The increasing emergence of resistance to commonly used antifungals (ex.:iazoles and polyenes) demonstrates an urgent need for alternative therapeutic strategies. The objective of this study was to evaluate the antifungal activity of novel organic derivatives from bioactive natural compound, including Naphthalene, Betulinic Acid (BA) [2]; Protocatechuic Acid (PCA) and Gallic Acid (GA), alone, or in combination with conventional antifungals to investigate synergistic effects that en-hance their efficacy. Antifungal susceptibility assays were performed in C. albicans ATCC 10231 using the broth microdilution method, according to CLSI M27 guidelines, to determine Minimum Inhibitory Concen-trations (MICs) and Minimum Fungicidal Concentra-tions (MFC). The interaction between BA derivatives and amphotericin B was assessed by checkerboard assay and fractional inhibitory concentration index (FICI). Naphthalene, PCA and GA derivatives showed low antifungal activity, falling within the moderate to weak bioactivity range (MIC ≥ 100 μg mL−1; [3]). Among BA derivatives, BA-4 and BA-5 exhibited the best antifungal activity, with MIC values of 0,95 and 1,91 μg mL−1, respectively, achieving 99% fungicidal activity at the same concentration. Furthermore, in combination assays, both compounds enhanced Am-photericin B activity, showing synergistic effects (FICI = 0.50), resulting in a decrease in MIC. Although most newly synthesized compounds exhibited limited anti-fungal potential, BA-4 and BA-5 demonstrated very strong bioactivity and fungicidal effects against C. albicans. The observed synergy with amphotericin B highlights their potential role as antifungal adjuvants and supports the further exploration of betulinic acid derivatives as viable approaches to overcoming anti-fungal resistance.
    2026-05-29Documento de conferência Acesso aberto Ver mais