Green Synthesis of Thiazole Derivatives using Multi-Component Reaction of Aldehydes, Isothiocyanate and Alkyl Bromides: Investigation of Antioxidant and Antimicrobial Activity.

2020 ◽  
Vol 23 ◽  
Author(s):  
Naghmeh Faal Hamedani ◽  
Leila Azad ◽  
Shahin Shafiee ◽  
Annataj Noushin
Keyword(s):  
Antimicrobial Activity ◽  
Disk Diffusion ◽  
Ferric Ion ◽  
Dpph Radical ◽  
Diffusion Test ◽  
Thiazole Derivatives ◽  
Disk Diffusion Test ◽  
Radical Trapping ◽  
Alkyl Bromides ◽  
Biological Potential

Aims & Objective: In this work, multicomponent reaction of aldehydes, benzoylisothiocyanate and alkyl bromides in the presence of ammonium acetate, sodium cyanide and catalytic amount of KF/Clinoptilolite nanoparticles (KF/CP NPs) in water at 100oC was investigated. Materials and Methods: In these reactions, thiazole derivatives produce in good to excellent yields and short time. Also, antioxidant activity was studied for the some newly synthesized compounds using the DPPH radical trapping and reducing of ferric ion experiments and comparing results with synthetic antioxidants (TBHQ and BHT). Results: As a result, compounds 4b show excellent DPPH radical trapping and reducing strength of ferric ion. These compounds have biological potential because of thiazole core. For this reason, the antimicrobial activity of some synthesized compounds was studied by employing the disk diffusion test on Gram-positive bacteria and Gram-negative bacteria. Conclusion: The results of disk diffusion test showed that these compounds prevented the bacterial growth.

KF/Clinoptilolite Nanoparticles as a Heterogeneous Catalyst for Green Synthesis of pyrido[2,1-a]isoquinolines using Four-Component Reaction of Alkyl Bromides

2020 ◽  
Vol 22 (10) ◽  
pp. 728-739
Author(s):  
Naghmeh F. Hamedani ◽  
Maryam Ghazvini ◽  
Fatemeh Sheikholeslami-Farahani ◽  
Mohammad T.B. Jamnani
Keyword(s):  
Heterogeneous Catalyst ◽  
Reducing Power ◽  
High Yield ◽  
Ferric Ion ◽  
Diffusion Test ◽  
Disk Diffusion Test ◽  
Radical Trapping ◽  
Alkyl Bromides ◽  
Isoquinoline Derivatives ◽  
Reducing Potential

Objective: KF/Clinoptilolite nanoparticles are employed as as a heterogeneous catalyst for the preparation of pyrido[2,1-a]isoquinoline derivatives through a four-component reaction of isoquinoline, two different alkyl bromides and an electron deficient internal alkynes at ambient temperature in water as green solvent. Methods: In this research, (2,2-Diphenyl-1-picrylhydrazyl) radical trapping and reducing potential of ferric ion experiments was used for determining antioxidant activity of some newly synthesized compounds such as 5a, 5c, 5f and 5g and comparing results with synthetic antioxidants (TBHQ and BHT). Results: Compounds 5a, 5c, 5f and 5g display trace DPPH radical trapping and excellent reducing power of ferric ion. Furthermore, the power of some prepared compounds against Gram-positive and Gram-negative bacteria was proved by employing the disk dispersion experiment. Conclusion: The obtained results of disk diffusion test showed that compounds 5a, 5d and 5e prevented the bacterial growth. The reported procedure shows the advantages of clean reaction, high yield and simple purification.

Bio-Fe3O4 magnetic nanoparticles promoted green synthesis of thioxo-1,3- oxazole derivatives: Study of antimicrobial and antioxidant activity

2020 ◽  
Vol 23 ◽  
Author(s):  
Maryam Ghazvini ◽  
Fatemeh Sheikholeslami-Farahani ◽  
Naghmeh Faal Hamedani ◽  
Ashraf Sadat Shahvelayati ◽  
Zohreh Rostami
Keyword(s):  
Sodium Hydride ◽  
Catalytic Amount ◽  
Disk Diffusion ◽  
Diffusion Test ◽  
Zno Nps ◽  
Alkyl Aryl ◽  
Disk Diffusion Test ◽  
Radical Trapping ◽  
Fe3o4 Mnps ◽  
Oxazole Derivatives

Aims and Objective: In this work 1,3-oxazoles were generated using multicomponent reaction of α-bromo ketones, alkyl (aryl) isothiocyanates, sodium hydride and Fe3O4 MNPs in water at room temperature in good yields. The nanoparticles that is generated via biosynthesis method have potentially valuable in different purposes such as organic synthesis. Materials and Methods: To study antioxidant ability of some synthesized thioxo-1,3-oxazoles, diphenyl-picrylhydrazine (DPPH) radical trapping and power of ferric reduction testes are employed. Among studied thioxo-1,3-oxazoles, 4b have good power for radical trapping and reduction activity than to standard antioxidant such as BHT and TBHQ. In addition, the antimicrobial activity of some thioxo-1,3-oxazoles was studied employing the disk diffusion test on Gram-positive bacteria and Gram-negative bacteria. The results of disk diffusion test showed that compound 4a, 4b, 4d and 4f prevented the bacterial growth. Results: Without employing catalyst, these reactions have low yield and busy mixture. The synthesis of compound 4a as sample reaction have alike yield in the presence of ZnO-NPs and Fe3O4 MNPs (entry 20 and entry 30) but removal of catalyst from the mixture of reaction after completing of reaction is comfortable in present of Fe3O4 MNPs. Structures of 4a–4i are confirmed by IR, 1H NMR, 13C NMR mass spectra. Conclusion: The reaction of α-bromo ketones, isothiocyanate and sodium hydride in the presence of catalytic amount of Fe3O4 MNPs in water generate 1,3-oxazole derivatives in good yields. Some advantages of performing these reactions with present procedure are carrying out these reactions in water as green solvent and simple removal of catalyst.

scholarly journals Evaluation of Mannitol Salt Agar for Detection of Oxacillin Resistance in Staphylococcus aureus by Disk Diffusion and Agar Screening

1998 ◽  
Vol 36 (8) ◽  
pp. 2254-2257 ◽  
Author(s):  
Günter Kampf ◽  
Christoph Lecke ◽  
Ann-Katrin Cimbal ◽  
Klaus Weist ◽  
Henning Rüden
Keyword(s):  
Staphylococcus Aureus ◽  
Disk Diffusion ◽  
Diffusion Test ◽  
Mannitol Salt Agar ◽  
Disk Diffusion Test ◽  
Zone Diameter ◽  
Oxacillin Resistance

Mannitol salt agar was evaluated for detection of oxacillin resistance in 136 Staphylococcus aureus isolates. AllmecA-positive isolates (n = 54) were correctly categorized as oxacillin resistant by the disk diffusion test (1-μg disk; zone diameter, <16 mm); the specificity was 97.6%. Agar screening (2 μg of oxacillin per ml) revealed a sensitivity of 98.1% and a specificity of 95.1%.

An alternative disk diffusion test in broth and macrodilution method for colistin susceptibility in Enterobacteriales

2019 ◽  
Vol 167 ◽  
pp. 105765
Author(s):  
López-Jácome Luis Esaú ◽  
Rengel-Garcia Christian Rodolfo ◽  
Hernández-Durán Melissa ◽  
Colín-Castro Claudia Adriana ◽  
García-Contreras Rodolfo ◽  
...  
Keyword(s):  
Disk Diffusion ◽  
Diffusion Test ◽  
Disk Diffusion Test

scholarly journals Ceftaroline resistance in Staphylococcus pseudintermedius gene mecA carriers

2018 ◽  
Vol 38 (12) ◽  
pp. 2233-2236
Author(s):  
Carolina B. Scherer ◽  
Larissa S. Botoni ◽  
Antônio U. Carvalho ◽  
Kelly M. Keller ◽  
Adriane P. Costa-Val
Keyword(s):  
Methicillin Resistance ◽  
Meca Gene ◽  
Disk Diffusion ◽  
Diffusion Test ◽  
Staphylococcus Pseudintermedius ◽  
Ceftaroline Fosamil ◽  
Disk Diffusion Test ◽  
Methicillin Resistant ◽  
Resistant Strains ◽  
Current Report

ABSTRACT: Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) being a constant concern, ceftaroline fosamil has been recently approved as a new cephalosporin, active against MRSA, for use in humans; only rare cases of resistance have been reported till date. There is no report of resistance to ceftaroline in Staphylococcus pseudintermedius, which is the main bacterium causing dermatitis and otitis in dogs. To evaluate staphylococcal resistance to ceftaroline, 35 isolates of methicillin-resistant S. pseudintermedius (MRSP), carrying the mecA gene, from 26 dogs with folliculitis and nine dogs with external otitis, underwent disk diffusion test with cefoxitin, oxacillin, and ceftaroline. Tests with cefoxitin and oxacillin showed > 90% sensitivity in methicillin resistance detection. In the disk diffusion test, 97.14% (34/35) were resistant to cefoxitin, 94.29% (33/35) to oxacillin, and 31.43% (11/35) to ceftaroline. Of the ceftaroline-resistant strains, 27.27% (3/11) were obtained from the ears of dogs while the rest (8/11) were from the skin. The current report is the first description of MRSP resistance to ceftaroline.

scholarly journals Ceftazidime-avibactam and Meropenem Double Disk Diffusion Test for Identifying Carbapanem-Resistant Enterobacteriaceae and Distinguishing Between Serine and Metallo-β-Lactamase Producing Organisms

2017 ◽  
Vol 4 (suppl_1) ◽  
pp. S375-S375
Author(s):  
Lynn-Yao Lin ◽  
Ian Critchley ◽  
David Melnick
Keyword(s):  
Enterobacter Cloacae ◽  
Disk Diffusion ◽  
Screening Methods ◽  
Diffusion Test ◽  
Disk Diffusion Test ◽  
Carbapenem Resistant ◽  
The Us ◽  
Susceptible Control ◽  
Carbapenem Resistant Enterobacteriaceae ◽  
Selection Of

Abstract Background Early detection of carbapenem-resistant Enterobacteriaceae(CRE) is crucial for selection of effective treatment. While KPC is the most prevalent carbapenemase in the US, phenotypic screening methods, such as the carbapenemase inactivation method (CIM) and CarbaNP, cannot easily distinguish between serine and metallo-β-lactamases (MBL). The aim of this study was to evaluate a simple double disk diffusion (DD) test to confirm carbapenem (meropenem) resistance (MER disk) and that resistance was due to a serine carbapenemase as indicated by susceptibility to ceftazidime-avibactam (CAZ-AVI disk). MBL-producing organisms are likely to be resistant to both MER and CAZ-AVI. Methods In total, 83 clinical isolates of Enterobacteriaceae were selected for the validation: 54 Klebsiella pneumoniae (KP), 16 Enterobacter cloacae (ECL) and 13 Escherichia coli (EC). All isolates were screened for specific β-lactamase genes (Checkpoints, Wageningen, Netherlands) and included KPC, OXA, IMP, VIM, NDM as well as strains with KPC and alterations on OmpK35 and OmpK36. Isolates were tested for susceptibility to MER and CAZ-AVI by disk diffusion and broth microdilution (BMD) per CLSI guidelines. Results were analyzed to evaluate suitability of the DD test to distinguish between serine and MBL-producing organisms. Results Overall correlation between disk and BMD was 97–100% for CAZ-AVI and 94–100% for MER. Among the 50 CRE that were susceptible to CAZ-AVI were strains positive for KPC, or OXA, or in combination with ESBLs. Among the 16 isolates that were resistant to both CAZ-AVI and MER were strains that produced MBLs such as IMP, VIM and NDM and included strains with alteration in OmpK35 and OmpK36. Among the 17 carbapenem-susceptible control strains all were susceptible to both agents and were positive for AmpC or ESBLs. Conclusion The CAZ-AVI and MER DD test was successful in confirming CRE phenotype and in distinguishing between serine carbapenemase-producing and MBL-producing organisms. The test will be useful in screening patients in future trials to evaluate the efficacy of CAZ-AVI in global CRE studies where MBL’s are more prevalent in other geographic regions. Both disks are commercially available and can be performed in most clinical laboratories. Disclosures L. Y. Lin, Allergan plc: Employee, Salary; I. Critchley, Allergan plc: Employee, Salary; D. Melnick, Allergan plc: Employee, Salary

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