Studies on antimicrobial activity of cobalt(III) ethylenediamine complexes

Abstract

A series of cobalt(III) mixed ligand complexes of type [Co(en)2L]+3, where L is bipyridine, 1,10-phenanthroline, imidazole, methylimidazole, ethyleimidazole, dimethylimidazole, urea, thiourea, acetamide, thioacetamide, semicarbazide, thiosemicarbazide, or pyrazole, have been isolated and characterized. The structural elucidation of these complexes has been explored by using absorption, infrared, and 1H NMR nuclear magnetic resonance spectral methods. The infrared spectral data of all these complexes exhibit a band at 1450/cm and 1560-1590/cm, which correspond to C=C and C=N, a band at 575/cm for Co-N (en), and a band at 480/cm for Co-L (ligand). All these complexes were found to be potent antimicrobial agents. The antibacterial activity was studied in detail in terms of zone inhibition, minimum bactericidal, and time period of lethal action. Among all, complexes bipyridine, 1,10-phenanthroline, dimethylimidazole, and pyrazole, possess the highest antibacterial activity. Antifungal activity was done by disc-diffusion assay and 50% inhibitory concentrations that possess high antifungal activity.

Binding of an anionic fluorescent probe with calf thymus DNA and effect of salt on the probe–DNA binding: a spectroscopic and molecular docking investigation

“…Hence, the absorbance increases sharply as the helix melts and the DNA strands separate. 52 Stabilization of the helix because of the intercalation of probes results in an increase in the helix melting temperature of the DNA. 35,45 On the contrary, groove binding leads to an inappreciable change in the T m value.…”

Synthesis, characterization, cytotoxic activity and DNA binding properties of the novel dinuclear cobalt(III) complex with the condensation product of 2-acetylpyridine and malonic acid dihydrazide

“…The ability of Co(III) complexes to mediate DNA cleavage has been well documented [35,40]. The effects of the complex [Co 2 L 2 ] 2+ on supercoiled DNA were studied using plasmid pUC18 in solution (Fig.…”

DNA as a target for antimicrobials

“…Rapid development of resistance is another factor that hampers the identification of novel antibiotics generally, and that is something that also cannot be avoided with DNAbinding compounds. After all, the short generation time of some bacteria (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30) minutes) provides plenty of scope for acquiring resistance genes or mutations that lead to resistance, in particular when that is compared to the speed at which novel antibiotics are introduced into the market (years). Expanding our arsenal with novel antimicrobials with barely utilised cellular targets may help us to stay ahead and prevent entering into a post-antibiotic era.…”