Posted by admin on Jul 31, 2021 in |
New pharmacologically active transition metal complexes of Co(II), Ni (II), Cu (II), and Zn(II) have been synthesized with the ligand 5-(2-(4-methoxyphenyl)-1H-benzo [d] imidazol-1-yl) quinolin-8-ol (2). Different analytical and spectroscopic tools were used to analyze the compounds, including elemental analysis, FTIR, 1H-NMR, mass spectra, electronic spectra, magnetic measurement, and molar conductance techniques. FTIR confirmed that the ligand coordinates the metal ion to form a mononuclear complex via the oxygen and nitrogen atoms of the phenolic and quinoline rings. For Co(II) and Zn(II) complexes, tetrahedral geometry is recommended, whereas square-planar geometry is proposed for Ni(II) and Cu(II) complexes. The antibacterial activity of the ligand and its metal complexes were assessed using the disc diffusion method, and minimum inhibitory concentration (MIC) was determined in the broth dilution technique. The antimicrobial activity results showed that the metal complexes were shown to be more active than the free ligand. Besides, Cu(II) complex was shown to be the most potent antioxidant using the DPPH and hydroxyl radical scavenging methods, with IC50 values of 17.3 and...
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Posted by admin on Jul 31, 2021 in |
This paper presents the antimicrobial activity of instant coffee, a prevalent beverage utilized by millions of people worldwide every day. Several studies have shown that instant coffee contains many useful bioactive compounds, the most important: caffeine, trigonelline, chlorogenic acid, ferulic acid, caffeic acid, nicotinic acid, and phenolic compounds which are responsible for the antimicrobial activity. In this study, six strains of resistant bacteria were selected as follows (Methicillin-resistant Staphylococcus aureus MRSA, S. aureus, Enterococcus faecalis, Escherichia coli, Klebsiella pneumonia, and Acinetobacter baumannii). The antibiotic sensitivity test revealed that the most tested bacterial strain was utterly resistant to the selected antibiotic discs. The antimicrobial activity of instant coffee was evaluated at different concentrations (20, 40, 60, and 80 mg/ml) against tested multi-drug resistant bacteria (MDR) and the fungi (A. niger and A. flavus). The results of antibacterial effect of instant coffee showed that the inhibition zone ranged between (7.6±0.5 and 19.6±0.5 mm). While the minimum inhibitory concentration (MIC) ranged between (62.5 and 32.25 mg/ml) against tested bacteria. Moreover, the instant...
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Posted by admin on Jun 30, 2021 in |
Schiff base was prepared by using 4-amino-3-hydroxy benzoic acid and 4-nitrobenzaldehyde, namely (E)-3-hydroxy-4-((4-nitrobenzylidene) amino)benzoic acid. In the preparation of rare earth complexes, nitrates of lanthanum, Cerium, and Praseodymium were used with Schiff base. Rare earth Schiff base complexes were prepared by using NaOH to maintain the pH of solvent. Synthesized Schiff base ligand and its complexes were structurally characterized by UV, IR, NMR, HRMS, TGA, and elemental analysis. Structural characterization shows 1:2 metal to ligand ratio in the complexes. The electronic absorption spectra of the ligands and their metal complexes are recorded after preparing the solution and after standing the solution for 3 weeks in DMF. No appreciable change was observed in the spectrum with time. Free ligands and their metal complexes have different electronic spectra’s and blue shift observed in complexes which support the complex formation. HRMS are in good agreement with calculated values, which confirms the proposed structure of ligand. Carboxylate group of Schiff base ligand shows bidentate the coordination to central metal and azomethine group is...
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Posted by admin on Jun 30, 2021 in |
In the present research worked aims to increase the antimicrobial activity of quinoxaline thiosemicarbazide derivatives by substitution of some acetophenones and their antimicrobial evaluation against various antimicrobial strains with molecular docking studies. Lead molecule (1E, 4E)-1-(7-chloro-3-isopropylquinoxalin-2(1H)-ylidene) thiosemicarbazide was synthesized and condensed with various substituted acetophenones to synthesize derivatives. All derivatives were characterized by IR., NMR & Mass spectroscopy. The synthesized derivatives were evaluated in-vitro for antibacterial and antifungal activities against various strains using the agar dilution method. Molecular docking studies of the derivatives (Va – Vg) were performed against E. coli DNA gyrase B and Topoisomerase IV to find out essential binding sites against target protein PDB: 1AJ6 and 1S14, respectively. Among all these compounds,Vf and Vg were found to exhibit more potent activity against Gram –Ve, Gram +Ve bacterial and fungal strains at MIC 0.19 µg/ml, 0.39µg/ml, and 0.78 µg/ml, respectively. The docking studies of all the compounds exhibit potent binding energy, but the compound Vg exhibit interactive binding energy -8.1 and -7.5 kcal/mol to the active pockets...
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Posted by admin on Jun 30, 2021 in |
Background and Objectives: Cyanobacteria are rich in various bioactive compounds. This study aims to screen the antimicrobial activity of sub-aerial Cyanobacteria isolated from sub-aerial habitats (Old monuments and building facades). Materials and Methods: Crude aqueous and organic extracts were screened for phytochemical constituents and tested for their antimicrobial efficacy against human pathogens. The crude extract that showed better antimicrobial activities were further fractionated by column chromatography and purified by TLC. The active bands were scraped out separately and concentrated in vacuo to isolate pure compounds. Each purified compounds dissolved in respective solvents, assayed for antimicrobial activities were further characterised through FTIR and LC-MS. Results: The results indicated the presence of many secondary metabolites. Of the isolated purified compounds, the compounds from three species, viz. Scytonema hyalinum, Tolypothrix rechingeri, and Fischerella species exhibited antimicrobial activities, whereas others showed antibacterial activity. The FTIR spectra revealed the peaks of carboxylic acid, alkaloids, and phenolic compounds. The chemical compounds were identified as 1,3-dihydroxycyclohexane [Lyngbya kuetzingiana], 4-(4-hydroxyphenyl) butanoic acid [Nostoc linckia], octahydro-1H-indole-2-carboxylic acid [Scytonema...
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