scholarly journals Synthesis, Characterization, and Biological Studies of New Ruthenium Polypyridyl Complexes Containing Noninnocent Ligands

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Sofia Taheri ◽  
Mahdi Behzad ◽  
Hossein Nazari ◽  
Ali Khaleghian
Keyword(s):  
Cyclic Voltammetry ◽  
Minimum Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Antibacterial Activities ◽  
Temperature Analysis ◽  
Ruthenium Polypyridyl ◽  
Polypyridyl Complexes ◽  
E Coli ◽  
Biological Studies ◽  
Ruthenium Polypyridyl Complexes

Two new polypyridyl complexes [Ru(ttp)(L1)Cl]PF6 (1) and [Ru(ttp)(L2)Cl]PF6 (2) with noninnocent o-benzoquinonediimine (L1; bqdi) and 4,5-dimethyle-o-benzoquinonediimine (L2; 4,5-di-Mebqdi) ligands were synthesized and characterized (ttp = -p-toloyle-2,: ,-terpyridine). Cyclic voltammetry studies suggest that noninnocent ligands are coordinated in their benzoquinonediimine form. Preliminary ruthenium complexes-induced DNA dysfunction was studied on E. coli GM109 DNA by means of melting temperature analysis (Tm). Our results suggest that complex (2) inhibited DNA function more strongly compared to (1). Antibacterial activities of the complexes against E. coli bacteria were studied, and Minimum inhibitory concentration (MIC) values were evaluated. Both complexes showed great antibacterial activities.

In Vitro Antibacterial activity of ethanolic extract of Myrsine africana against laboratory Strains of Pathogenic Organisms

2016 ◽  
Vol 5 (04) ◽  
pp. 4512
Author(s):  
Jackie K. Obey ◽  
Anthoney Swamy T* ◽  
Lasiti Timothy ◽  
Makani Rachel
Keyword(s):  
Antibacterial Activity ◽  
Minimum Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Ethanolic Extract ◽  
Ethanol Extract ◽  
E Coli ◽  
Zones Of Inhibition ◽  
In Vitro Antibacterial Activity ◽  
Myrsine Africana

The determination of the antibacterial activity (zone of inhibition) and minimum inhibitory concentration of medicinal plants a crucial step in drug development. In this study, the antibacterial activity and minimum inhibitory concentration of the ethanol extract of Myrsine africana were determined for Escherichia coli, Bacillus cereus, Staphylococcus epidermidis and Streptococcus pneumoniae. The zones of inhibition (mm±S.E) of 500mg/ml of M. africana ethanol extract were 22.00± 0.00 for E. coli,20.33 ±0.33 for B. cereus,25.00± 0.00 for S. epidermidis and 18. 17±0.17 for S. pneumoniae. The minimum inhibitory concentration(MIC) is the minimum dose required to inhibit growth a microorganism. Upon further double dilution of the 500mg/ml of M. africana extract, MIC was obtained for each organism. The MIC for E. coli, B. cereus, S. epidermidis and S. pneumoniae were 7.81mg/ml, 7.81mg/ml, 15.63mg/ml and 15.63mg/ml respectively. Crude extracts are considered active when they inhibit microorganisms with zones of inhibition of 8mm and above. Therefore, this study has shown that the ethanol extract of M. africana can control the growth of the four organisms tested.

scholarly journals Transcriptome analysis of Escherichia coli K1 after therapy with hesperidin conjugated with silver nanoparticles

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Abdulkader Masri ◽  
Naveed Ahmed Khan ◽  
Muhammad Zarul Hanifah Md Zoqratt ◽  
Qasim Ayub ◽  
Ayaz Anwar ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Silver Nanoparticles ◽  
Minimum Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Neonatal Meningitis ◽  
E Coli ◽  
Drug Candidates ◽  
Metabolic Genes ◽  
Genetic Mechanisms ◽  
Cell Stress Response

Abstract Backgrounds Escherichia coli K1 causes neonatal meningitis. Transcriptome studies are indispensable to comprehend the pathology and biology of these bacteria. Recently, we showed that nanoparticles loaded with Hesperidin are potential novel antibacterial agents against E. coli K1. Here, bacteria were treated with and without Hesperidin conjugated with silver nanoparticles, and silver alone, and 50% minimum inhibitory concentration was determined. Differential gene expression analysis using RNA-seq, was performed using Degust software and a set of genes involved in cell stress response and metabolism were selected for the study. Results 50% minimum inhibitory concentration with silver-conjugated Hesperidin was achieved with 0.5 μg/ml of Hesperidin conjugated with silver nanoparticles at 1 h. Differential genetic analysis revealed the expression of 122 genes (≥ 2-log FC, P< 0.01) in both E. coli K1 treated with Hesperidin conjugated silver nanoparticles and E. coli K1 treated with silver alone, compared to untreated E. coli K1. Of note, the expression levels of cation efflux genes (cusA and copA) and translocation of ions, across the membrane genes (rsxB) were found to increase 2.6, 3.1, and 3.3- log FC, respectively. Significant regulation was observed for metabolic genes and several genes involved in the coordination of flagella. Conclusions The antibacterial mechanism of nanoparticles maybe due to disruption of the cell membrane, oxidative stress, and metabolism in E. coli K1. Further studies will lead to a better understanding of the genetic mechanisms underlying treatment with nanoparticles and identification of much needed novel antimicrobial drug candidates.

Influence of the Attaching Group and Substituted Position in the Photosensitization Behavior of Ruthenium Polypyridyl Complexes

1999 ◽  
Vol 38 (26) ◽  
pp. 6320-6322 ◽  
Author(s):  
Yuan-jun Hou ◽  
Pu-hui Xie ◽  
Bao-wen Zhang ◽  
Yi Cao ◽  
Xu-rui Xiao ◽  
...  
Keyword(s):  
Ruthenium Polypyridyl ◽  
Polypyridyl Complexes ◽  
Ruthenium Polypyridyl Complexes

scholarly journals A comparison of the antibacterial activity of some African black soaps and medicated soaps commonly used for the treatment of bacteria-infected wound

2017 ◽  
Vol 1 (1) ◽  
Author(s):  
Olufunmiso O. Olajuyigbe ◽  
Morenike O. Adeoye-Isijola ◽  
Otunola Adedayo
Keyword(s):  
Antibacterial Activity ◽  
Inhibitory Concentration ◽  
Waste Product ◽  
Antibacterial Activities ◽  
Traditional Use ◽  
E Coli ◽  
African Black ◽  
Soap Production ◽  
Inhibition Zones ◽  
Better Than

Background: Black soap is a medicinal product that could be harnessed for economic purpose if properly packaged, and misconception about its traditional use by herbalists is thrown overboard.Aims: To promote the relevance of these soaps for economic development, this study compared the antibacterial activity of black soaps with medicated soaps widely used against bacterial infections.Methods: The antibacterial activities of these soap samples were determined by agar diffusion and macrobroth dilution methods.Results: In this study, the statistical analysis of the inhibition zones showed that black soaps were significantly (p < 0.05) more active than medicated soaps used against the test bacterial isolates. The black soaps inhibited and killed the isolates better than the medicated soaps at the different concentrations used. The minimum inhibitory concentration for Klebsiella pneumoniae and Enterococcus faecalis ranged between 0.125 mg/mL and 2 mg/mL, Staphylococcus aureus (0.25–4) mg/mL, Escherichia coli (0.125–4) mg/mL and Pseudomonas aeruginosa (1–4) mg/mL. The result showed that K. pneumoniae and E. faecalis were the most susceptible, followed by E. faecalis > E. coli > S. aureus > P. aeruginosa.Conclusion: As a valuable medicinal output derivable from organic waste product that could be converted to wealth, African black soap production, utilisation and commercialisation have tremendous economic potentials. These soaps showed significant antibacterial activity greater than those of the medicated soaps. Hence, their use could be a better option in place of commercially available medicated and antiseptic soaps because of the degree of antibacterial activities they exhibited.

Preparation and disinfection properties of graphene oxide/trichloroisocyanuric acid disinfectant

2021 ◽  
Author(s):  
li li jiang ◽  
Su Xu ◽  
Haitao Yu ◽  
Qi Cui ◽  
Rui Cao
Keyword(s):  
Electron Microscopy ◽  
Graphene Oxide ◽  
Minimum Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Kinetic Curve ◽  
X Ray ◽  
Bacterial Inhibition ◽  
E Coli ◽  
Blending Method ◽  
Trichloroisocyanuric Acid

Abstract In this study, graphene oxide (GO) was first prepared by the modified Hummer method. Then, the GO/trichloroisocyanuric acid (TCCA) composite was prepared by loading TCCA into GO with the blending method. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and atomic force microscopy were used to characterize the composite. The results showed that TCCA was successfully loaded on the surface of GO or intercalated among GO layers. Next, the antibacterial performance of the composite against Escherichia coli and Staphylococcus aureus was tested by the 96-well plate assay. A bactericidal kinetic curve, bacterial inhibition tests, and the mechanism of bacterial inhibition is discussed. The results showed that the minimum inhibitory concentration of the GO/TCCA composite (GO:TCCA ratio = 1:50) was 327.5 µg/mL against E. coli and 655 µg/mL against S. aureus. At the minimum inhibitory concentration, the inhibition rate of the GO/TCCA composite exceeded 99.46% against E. coli and 99.17% against S. aureus. The bactericidal kinetic curves indicate that the GO/TCCA composite has an excellent bactericidal effect against E. coli and S. aureus.

Modulation of Internuclear Communication in Multinuclear Ruthenium(II) Polypyridyl Complexes

2003 ◽  
Vol 68 (8) ◽  
pp. 1467-1487 ◽  
Author(s):  
Wesley R. Browne ◽  
Frances Weldon ◽  
Adrian Guckian ◽  
Johannes G. Vos
Keyword(s):  
Ground State ◽  
Weak Interactions ◽  
Electrochemical Studies ◽  
Protonation State ◽  
Ruthenium Polypyridyl ◽  
Bridging Ligands ◽  
Polypyridyl Complexes ◽  
Bridging Ligand ◽  
Dinuclear Ruthenium ◽  
Ruthenium Polypyridyl Complexes

The syntheses and characterisation of a series of mononuclear and dinuclear ruthenium polypyridyl complexes based on the bridging ligands 1,3-bis-[5-(2-pyridyl)-1H-1,2,4-triazol-3-yl]benzene, 1,4-bis-[5-(2-pyridyl)-1H-1,2,4-triazol-3-yl]benzene, 2,5-bis-[5-(2-pyridyl)-1H-1,2,4-triazol-3-yl]thiophene, 2,5-bis-[5-pyrazinyl-1H-1,2,4-triazol-3-yl]thiophene are reported. Electrochemical studies indicate that in these systems, the ground state interaction is critically dependent on the nature of the bridging ligand and its protonation state, with strong and weak interactions being observed for thiophene- and phenylene-bridged complexes, respectively.

scholarly journals Quantitative description of MLCT transitions in ruthenium polypyridyl complexes probed by two-photon absorption spectroscopy

2018 ◽  
Vol 190 ◽  
pp. 03012
Author(s):  
Charles W. Stark ◽  
M. Rammo ◽  
K. Petritšenko ◽  
J. Pahapill ◽  
A. Mikhaylov ◽  
...  
Keyword(s):  
Cross Section ◽  
Quantitative Description ◽  
Photon Absorption ◽  
Charge Transfer Transition ◽  
Ruthenium Polypyridyl ◽  
Polypyridyl Complexes ◽  
Two Photon Absorption ◽  
Two Photon ◽  
Ligand Charge Transfer ◽  
Ruthenium Polypyridyl Complexes

Quantitative two-photon absorption (2PA) cross section and 2PA spectrum measurements were used to determine the molecular electric dipole change in the metal-to-ligand charge-transfer transition of ruthenium(II) tris-complexes of 2,2’-bipyridine ([Ru(bpy)3]2+) and 1,10-phenanthroline ([Ru(phen)3]2+) in several solvents.

Sign in / Sign up

Export Citation Format

Share Document