Silver(I) complexes with phthalazine and quinazoline as effective agents against pathogenic Pseudomonas aeruginosa strains

Biogenic synthesis of Zinc oxide nanostructures from Nigella sativa seed: Prospective role as food packaging material inhibiting broad-spectrum quorum sensing and biofilm

“…Figure 12 shows significant reduction in preformed biofilms of all tested bacterial pathogens upon treatment with sub-inhibitory concentrations of NS-ZnNPs. Our results are in accordance with the previous report where Silver(I) complexes with phthalazine and quinazoline demonstrated marked ability to disrupt mature biofilms of P. aeruginosa 57. Extract of Capparis spinosa also showed significant reduction in the preformed biofilms of Escherichia coli, Proteus mirabilis, Serratia marcescens and PAO158.…”

Synthesis, Structural Characterization and Antimicrobial Evaluation of Ruthenium Complexes with Heteroaromatic Carboxylic Acids

“…The high activity was detected for the compound 1 against bacterium of P. aeruginosa PAO1 with the MIC value 0.5 m m (302 μg/ml). Considering the MIC values for other transition metal complexes towards P. aeruginosa PAO1 (Ag(I) complexes – MIC=2–15 μg/ml, Au(III) complexes – MIC=10−30 μg/ml, Cu(II) complexes – MIC=500–1000 μg/ml), it can be concluded that the tested ruthenium complexes show moderate bacteriostatic activity. In comparison to tested antibiotic, the studied ruthenium compounds exhibit much lower bacteriostatic effects on the bacteria.…”

“…Biologically active metal complexes have gained special significance due to the need for the prevention of resistance of bacterial strains. Recently, several Cu(II), Ga(III), Zn(II), Mn(II), Ag(I), Au(III) and Ru(II) complexes with bioactive ligands have been tested as potential antibiofilm and antimicrobial agents . Among above mentioned metal complexes, ruthenium compounds are promising for medicinal and biotechnological applications as they present unique properties: (i) multiple oxidation states (II, III and IV), which are accessible in physiological conditions; (ii) favorable ligand‐exchange kinetics; (iii) multiple cytotoxic routes involving the competing processes of extracellular protein binding (active transport), due to the ability to mimic iron and cellular uptake (passive diffusion); (iv) different molecular pathways involving the concurrent intercalation and covalent binding with DNA and binding to extracellular sites inducing conformational modifications; (v) numerous synthetic opportunities for modifying the biological activity which depends on both the oxidation state of the metal center and the associated ligands surrounding it.…”

Synthesis and structural analysis of polynuclear silver(I) complexes with 4,7-phenanthroline

“…The Ag1-N1/N2(4,7-phen) bond distances in 1 ( Table I) adopt values of 2.305(5) and 2.251(5) Å, respectively, and are comparable with those observed in the other pseudo tetrahedral silver(I) complexes with aromatic N-heterocycles. [8][9][10][11][12][13][14] The Ag1-N3 (acetonitrile) bond distance of 2.284 (7) Å falls in the normal range of 2.18-2.33 Å. 26 On the other hand, the Ag1-O1 bond distance of 2.505(6) Å is much longer than usual covalent silver(I)-oxygen bonds of approximately 2.3 Å.…”

“…1,2 Generally, silver(I) complexes with these ligands are known to possess significant antibacterial activity against a wide range of Gram-positive and Gram-negative bacteria and have shown remarkable activity against different Candida species. [3][4][5][6][7][8][9][10][11][12][13][14] Moreover, they have manifested cytotoxic activity against different human tumor cell line, being more active and less toxic to humans than the clinically used platinum(II) complexes. 15 Their effectiveness is thought to be the consequence of the presence of a weak Ag−N bond, which can be easily cleaved in the interaction with thiol-containing proteins and DNA, the process that is a prerequisite for their action.…”