Antifungal activity and phytotoxicity of the ternary complex of copper(II) with cyanoguanidine and 1,10-phenanthroline

LORENA E. GUEVARA; JUAN J. MARTÍNEZ MEDINA

Rosario

Congreso; LIX Annual Meeting of the Argentine Society for Biochemistry and Molecular Biology Research (SAIB); 2023

Sociedad Argentina de Investigación Bioquímica

We previously reported the molecular structure, bioavailability and bioactivity of the ternary [Cu(phen)(cnge)(H2O)(NO3)2] complex (Cu/phen/cnge). The antifungal activity of this complex was determined against one strain derived from the American Type Culture Collections (ATCC) namely Candida parapsilosis ATCC 22019 and two strains from clinical isolates (C. albicans and C. tropicalis). It is known that the strains responsible for infectious diseases in hospitals could show different resistance profiles than the ATCC strains. In this context, we decided to extend the antifungal evaluation of the Cu/phen/cnge complex including another ATCC strain and clinical isolates of Candida genus, which were kindly provided by hospitals of Chaco. The antimicrobial studies were coupled with the phytoxicity evaluation, in order to broaden safety studies previously carried out for this complex.The results showed that the Cu/phen/cnge complex has antifungal activity clinically relevant with MIC values between 3.9 and 15.6 μg/mL for most of the tested strains (except for the strains of C. parapsilosis). The MIC values for both ATCC and clinical isolate of C. albicans are the same, whereas the MIC value for C. parapsilosis from clinical isolate was higher than that for the ATCC strain. This result suggests a higher resistance profile for the clinical isolate strain. The MIC values for antifungal activity are slightly higher than the IC50 of the complex in A. cepa. Nevertheless, we previously demonstrated that the complex did not exert acute toxicity on Artemia salina until 750 μg/mL. In summary, the complexation is a useful strategy for designing novel antifungal agents.