scholarly journals Biologically Active Co(II) and Ni(II) Complexes of N-(2-Thienylmethylene)-2-Aminothiadiazole

2002 ◽  
Vol 8 (6) ◽  
pp. 323-327 ◽  
Author(s):  
Zahid H. Chohan

Co(II) and Ni(II) complexes Schiff base, N-(2-thienylmethylene)-2-aminothiadiazole have been prepared and characterized by their physical, spectral and analytical data. The title Schiff-base acts as NNS donor tridentate during the complexation reaction with these metal ions having a composition, [M(L)2]Xn where M=Co(II) or Ni(II), L=, X=NO3− , SO42− , C2O42− or CH3CO2− and n=1 or 2 and show an octahedral geometry. In order to evaluate the effect anions upon chelation, the Schiff-base and its new complexes have been screened for their antibacterial activity against bacterial strains e.g., Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa.

2002 ◽  
Vol 8 (5) ◽  
pp. 287-291 ◽  
Author(s):  
Zahid H. Chohan ◽  
Abdul Rauf ◽  
Claudiu T. Supuran

Co(II) and Ni(II) complexes with a Schiff base, N-(2-furanylmethylene)-2-aminothiadiazole have been prepared and characterized by their physical, spectral and analytical data. The synthesized Schiff-bases act as tridentate ligands during the complexation reaction with Co(II) and Ni(II. metal ions. They possess the composition [M(L)2]Xn (where M=Co(II) or Ni(II), L=, X=NO3− , SO42− , C2O42− or CH3CO2− and n=1 or 2) and show an octahedral geometry. In order to evaluate the effect of anions upon chelation, the Schiff-base and its complexes have been screened for antibacterial activity against bacterial strains e.g., Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa.


1998 ◽  
Vol 5 (5) ◽  
pp. 267-274 ◽  
Author(s):  
Zahid H. Chohan ◽  
Marapaka Praveen ◽  
Syed K. A. Sherazi

Biologically active complexes of Co(II), Ni(II), Cu(II) and Zn(II) with novel ONO, NNO and SNO donor pyrazinoylhydrazine-derived compounds have been prepared and characterized on the basis of analytical data and various physicochemical studies. Distorted octahedral structures for all the complexes have been proposed. The synthesized ligands and their complexes have been screened for their antibacterial activity against bacterial species Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Klebsiella pneumonae. The activity data show the metal complexes to be more active than the parent free ligands against one or more bacterial species.


2000 ◽  
Vol 7 (5) ◽  
pp. 265-269 ◽  
Author(s):  
Zahid H. Chohan ◽  
Maimoon F. Jaffery

Some Co(II), Cu(II), Ni(II) and Zn(II) complexes of antibacterial drug cephradine have been prepared and characterized by their physical, spectral and analytical data. Cephradine acts as bidentate and the complexes have compositions, [M(L)2X2] where [M = Co(II), Ni(II) and Zn(II), L = cephradine and X = Cl2] showing octahedral geometry, and [M(L)2] where [M = Cu(II), L = cephradine] showing square planar geometry. In order to evaluate the effect of metal ions upon chelation, eephradine and its complexes have been screened for their antibacterial activity against bacterial strains, Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa.


2021 ◽  
Vol 5 (1) ◽  
pp. 1-9
Author(s):  
Antonio Carlos Pereira de Menezes Filho ◽  
Matheus Vinícius Abadia Ventura ◽  
Carlos Frederico de Souza Castro

Tibouchina granulosa is a species that blooms annually in several regions of Brazil. This species is still little explored in terms of phytocompounds in all organs of this plant, especially the floral organ. Flowers of T. granulosa were collected in the municipality of Rio Verde, Goiás, Brazil, in 2021. The hydroethanolic floral extract was prepared by maceration and qualitative phytochemical (colorimetric reactions and salt formation) and antibacterial analyzes performed and the results expressed in millimeters of inhibition at different concentrations in mg mL-1. Several phytochemical classes were observed with positive results, especially for alkaloids, phenolics, oxylates, saponins, carbohydrates and tannins. As for the bacterial assay, potential antibacterial activity was observed for all bacterial strains tested, except for Salmonella serovar Thyphymurium and serovar Enteritidis. Expressive inhibitions were observed for Enterococcus faecalis > Pseudomonas aeruginosa > Staphylococcus aureus and Escherichia coli at the highest concentrations between 100-50 mg mL-1. The floral extract of Tibouchina granulosa showed phytotherapeutic potential with the presence of several phytochemical groups and expressive antibacterial activity.


2022 ◽  
Vol 11 (1) ◽  
pp. 75-82 ◽  
Author(s):  
Iryna Myrko ◽  
Taras Chaban ◽  
Vasyl Matiychuk

A series of some new pyrazole-substituted 7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazines was synthesized in this study. The structures of target substances were confirmed by using 1H and 13С NMR spectroscopy, mass spectrometry and elemental analysis. The synthesized compounds have been evaluated for antimicrobial activity against five bacterial strains (Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus) and two fungal strains (Candida albicans and Cryptococcus neoformans). The antimicrobial screening studies of synthesized substances established that 2 of 12 compounds show pronounced antibacterial activity against the strain Staphylococcus aureus.


2019 ◽  
Vol 32 (1) ◽  
pp. 192-194
Author(s):  
S. Sudha Kumari

In present work, the screening of antimicrobial activities of copper(II) and cobalt(II) complexes with Schiff base ligand derived from the condensation of citral with valine (amino acid) was carried out on agar plates are reported. The antibacterial activity of Schiff base and its copper(II) and cobalt(II) complexes were evaluated against two bacterial strains Staphylococcus aureus (Gram-positive), Escherichia coli (Gram-negative) and fungus Candida albicans. The results revealed that the Schiff base ligand exhibited the poor antimicrobial activity against Escherichia coli and Candida albicans except for Staphylococcus aureus. Generally, Gram-negative bacteria shows rigid outer membrane, well enough to defend against the drug but Schiff base (citral with valine derived) impregnated cobalt(II) complex seem to be more active against Escherichia coli organisms in comparison to copper(II) complex, which exhibits higher activity than uncomplexed ligand. The antimicrobial results revealed that cobalt(II) and copper(II) complexes have a considerable antibacterial activity than antifungal activity and suggest their potential application as antibacterial agents.


2001 ◽  
Vol 8 (2) ◽  
pp. 95-101 ◽  
Author(s):  
Zahid H. Chohan ◽  
Maimoon F. Jaffery ◽  
Claudiu T. Supuran

Schiff bases were obtained by condensation of 2-amino-l,3,4-thiadiazole with 5-substituted-salicylaldehydes which were further used to obtain complexes of the type [M(L)2]Cl2, where M=Co(II), Cu(II), Ni(II) or Zn(II). The new compounds described here have been characterized by physical, spectral and analytical data, and have been screened for antibacterial activity against several bacterial strains such as Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. The antibacterial potency of these Schiff bases increased upon chelation/complexation, against the tested bacterial species, opening new aproaches in the fight against antibiotic resistant strains.


2018 ◽  
Vol 16 (S1) ◽  
pp. S155-S163 ◽  
Author(s):  
S. Mehalaine ◽  
O. Belfadel ◽  
T. Menasria ◽  
A. Messaili

The present study was carried out to determine, for the first time, the chemical composition and antibacterial activity of essential oils derived from the aerial parts of three aromatic plants Thymus algeriensis Boiss & Reut, Rosmarinus officinalis L., and Salvia officinalis L. growing under semiarid conditions. The essential oils were chemically analyzed and identified by gas chromatography (GC) and GC/ mass spectrometry (GC/MS) and their antimicrobial activity was individually evaluated against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa using both agar disk diffusion and agar dilution methods. The major constituents of Thymus algeriensis essential oil were identified as camphor (13.62%), 1,8-cineol (6.00%), borneol (5.74%), viridiflorol (4.00%), and linalool (3.93%). For Rosmarinus officinalis essential oil, 48 compounds were characterized, of which the main constituents were camphor (17.09%), Z-β-ocimene (10.88%), isoborneol (9.68%), α-bisabolol (7.89%), and borneol (5.11%). While, Salvia officinalis essential oil was characterized by β-thujone (16.44%), followed by viridiflorol (10.93%), camphor (8.99%), 1,8-cineol (8.11%), trans-caryophyllene (5.85%), and α-humulene (4.69%) as the major components. Notably, results from antibacterial screening indicated that Thymus algeriensis and Salvia officinalis essential oils exhibited a strong inhibitory effect against both Escherichia coli and Staphylococcus aureus compared to Rosmarinus officinalis essential oil. Further, less activity was recorded against Pseudomonas aeruginosa for the three tested essential oils.


2018 ◽  
Vol 21 (0) ◽  
Author(s):  
Flávia Cíntia de Oliveira ◽  
Tamara Rezende Marques ◽  
Gustavo Henrique Andrade Machado ◽  
Thaís Cristina Lima de Carvalho ◽  
Aline Aparecida Caetano ◽  
...  

Abstract The phenolic compounds from various extracts of jabuticaba skin powder (JSP) were characterized in this study, and the antibacterial activity assessed. The phenolic compounds were extracted from the JSP using four methods: a) acetone extraction - 1 g JSP: 10 mL 70% acetone, resting for 2 hours; b) aqueous extract - 1 g JSP: 15 mL water, under agitation; c) ethanolic extract - 1 g JSP: 15 mL acidified ethanol, under agitation; and d) methanolic extract - 1 g JSP: 50 mL 50% methanol, under reflux. The antibacterial activity was evaluated by the agar diffusion assay, using Escherichia coli ATCC 11229, Salmonella choleraesuis ATCC 6539, Pseudomonas aeruginosa ATCC 15442, Staphylococcus aureus ATCC 6538 and Listeria monocytogenes ATCC 19117. The ethanolic and methanolic extracts showed the highest levels of phenolic compounds, especially of cyanidin chloride, catechin and epicatechin. The extracts did not inhibit the growth of Escherichia coli and Salmonella choleraesuis, but inhibited 30% of the growth of Pseudomonas aeruginosa with an extract concentration of 250 µg mL-1. Against Staphylococcus aureus and Listeria monocytogenes the highest inhibitory effect observed was 41.8% for the ethanolic extract, followed by 36% inhibition by the methanolic extract, thus revealing the potential of these extracts as possible alternatives for use in the food and/or pharmaceutical industries.


Author(s):  
A. A. Katun ◽  
A. R. Abdulmumin ◽  
M. U. Yahaya ◽  
N. K. Habeeb ◽  
A. Bala

The investigation into soil bacteria has been widely studied and becoming increasingly appreciated as an exceptional reservoir of unique naturally occurring biologically active metabolites with pharmaceutical applications. This article aimed to isolate, identify and biochemically characterize antibiotic-producing bacteria from anthill soils in the permanent site of Ibrahim Badamasi Babangida University, Lapai (IBBUL), Niger State, Nigeria. The sum of ten samples were collected from five sampling sites, the sampling was done in threefold (morning, noon and evening) and analyzed adopting standard microbiological protocols. The obtained result revealed that the total bacteria count in the morning ranges from 2.1×107 cfu/mL to 1.4×106 cfu/mL, noon count ranges from 3.1×107 to 2.6×106 cfu/mL while evening count was in the range of 2.1×107 cfu/mL to 1.7×106 cfu/mL. A total number of five (5) bacteria were isolated as Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Bacillus lentus and Micrococcus reseus. The total prevalence of the bacterial isolates in the morning, noon and evening were calculated as B. subtilis (109.08%), S. epidermidis (36.36%), M. reseus (36.36%), B. lentus (63.63%), and S. aureus (54.54%) respectively. These isolates were further assayed against Escherichia coli, Salmonella typhi, Klebsiella sp. and Staphylococcus aureus. The antibacterial outcome showed that two (2) (40%) anthill isolates exhibited antibacterial activity against three (3) tested bacteria (Escherichia coli, Salmonella typhi and Staphylococcus aureus). This research study has showcased that the production of inhibitory substances are common among some of the bacterial strains isolated from anthills.


Sign in / Sign up

Export Citation Format

Share Document