Antimicrobial Activity of Silver Camphorimine Complexes against Candida Strains

• Published in: Antibiotics (Basel) Vol. 8; no. 3; p. 144
• Main Authors: Costa, Joana P, Pinheiro, M Joana F, Sousa, Sílvia A, Botelho do Rego, Ana M, Marques, Fernanda, Oliveira, M Conceição, Leitão, Jorge H, P Mira, Nuno, N N Carvalho, M Fernanda
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 10.09.2019; MDPI
• Subjects: Acetates; anti-Candida activity; Anti-infective agents; antibacterials; antifungals; Antiinfectives and antibacterials; Antimicrobial activity; Antimicrobial agents; Bacteria; Biphenyl (Compound); Bromine compounds; camphorimine; Candida; Chemical analysis; Chloride; Control; Coordination compounds; Cytotoxicity; E coli; Escherichia coli; Evaluation; Fibroblasts; Halides; Health aspects; Hydroxides; Infections; Ligands; Mass spectra; Mass spectroscopy; Microorganisms; Minimum inhibitory concentration; Nitrates; NMR; Nuclear magnetic resonance; Photoelectron spectroscopy; Photoelectrons; Pseudomonas aeruginosa; Public health; Silver; Silver chloride; silver complexes; Silver compounds; Spectroscopy; Spectrum analysis; Staphylococcus aureus; Staphylococcus aureus infections; Strains (organisms); Tetracyclines; Toxicity; X ray photoelectron spectroscopy; X-ray spectroscopy; Portugal; antibacterials; anti-Candida activity; camphorimine; silver complexes; antifungals
• ISSN: 2079-6382; 2079-6382
• DOI: 10.3390/antibiotics8030144

Hydroxide [Ag(OH)L] (L = L, L, L, L), oxide [{AgL} }(μ-O)] (L = L, L, L, L, L) or chloride [Ag L]Cl, [Ag( L) ]Cl complexes were obtained from reactions of mono- or bicamphorimine derivatives with Ag(OAc) or AgCl. The new complexes were characterized by spectroscopic (NMR, FTIR) and elemental analysis. X-ray photoelectron spectroscopy (XPS), ESI mass spectra and conductivity measurements were undertaken to corroborate formulations. The antimicrobial activity of complexes and some ligands were evaluated towards and , and strains of the bacterial species , , and based on the Minimum Inhibitory Concentrations (MIC). Complexes displayed very high activity against the species studied with the lowest MIC values (3.9 µg/mL) being observed for complexes and against . A significant feature of these redesigned complexes is their ability to sensitize , a trait that was not found for the previously investigated [Ag(NO )L] complexes. The MIC values of the complexes towards bacteria were in the range of those of [Ag(NO )L] and well above those of the precursors Ag(OAc) or AgCl. The activity of the complexes towards normal fibroblasts V79 was evaluated by the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay. Results showed that the complexes have a significant cytotoxicity.