scholarly journals Synthesis, spectroscopic characterization and pharmacological evaluation of oxazolone derivatives

2013 ◽  
Vol 78 (8) ◽  
pp. 1127-1134 ◽  
Author(s):  
Ghulam Fareed ◽  
Nighat Afza ◽  
Ali Versiani ◽  
Nazia Fareed ◽  
Rasheed Mughal ◽  
...  

A series of 4-aryl methylidene-2-phenyl/methyl-5-(4H)-oxazolone derivatives (2-7) have been synthesized using the reported method by condensation of aldehydes with N-benzoyl / N-acetyl glycine in the presence of zinc oxide as a catalyst and acetic anhydride at room temperature in ethanol. The compounds (2-6) are new derivatives. The structures of compounds were evaluated on the basis of 1H-NMR, 13C-NMR, EIMS, FT-IR and elemental analysis. All the compounds were screened for their antibacterial and urease inhibition activity. Antibacterial activity was tested by agar well diffusion method using Mueller Hinton Agar medium. Compound (2) showed excellent activity against S. aureus which has 16 mm (80%) inhibition and above 24 mm (70%) against S. typhi. The most active compound against E. coli was compound (6) having 20 mm (80%) inhibition followed by compound (5) having above 18 mm (70%) inhibition. Urease inhibition activity of all the compounds was determined by indophenol method. Compounds (3, 6) and (7) showed significant inhibition against Jacks bean urease.

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Anwar Ali Chandio ◽  
Ayaz Ali Memon ◽  
Shahabuddin Memon ◽  
Fakhar N. Memon ◽  
Qadeer Khan Panhwar ◽  
...  

Present study deals with the synthesis of the p-tert-butylcalix[4]arene diamide derivative as ligand (L) and its Fe3+ complex, followed by its characterization using TLC and FT-IR, while UV-Vis and Job’s plot study were performed for complex formation. Antimicrobial activity of the derivative (L) and its metal complex was carried out by the disc diffusion method against bacteria (Escherichia coli and Staphylococcus albus) and fungi (R. stolonifer). Different concentrations of the derivative (L) (6, 3, 1.5, 0.75, and 0.37 μg/mL) and its Fe3+ complex were prepared, and Mueller–Hinton agar was used as the medium for the growth of microorganisms. Six successive dilutions of the derivative (L) and Fe3+ complex were used against microorganisms. Two successive dilutions (6 and 3 μg/mL) of the derivative (L) showed antibacterial action against both Gram-positive and Gram-negative bacteria. In addition, three successive dilutions (6, 3, and 1.5 μg/mL) of the derivative (L) showed antifungal activity. However, all of six dilutions of the Fe3+ complex showed antimicrobial activity. Derivative (L) showed 3 and 1.5 μg/mL minimum inhibitory concentrations (MIC) against bacteria and fungi, respectively. On the contrary, its Fe3+ complex showed 0.37 μg/mL value of MIC against bacteria and fungi. Hence, Fe3+ complex of the derivative (L) was found to be a more effective antimicrobial agent against selected bacteria and fungi than the diamide derivative (L).


2021 ◽  
Vol 12 (6) ◽  
pp. 7159-7176

The substituted chalcone derivatives 1–7 have been synthesized, and spectroscopic characterization were done as done using the experimental FT-IR, UV-Vis, GC-MS, 1D NMR spectroscopy. The favored conformation of substituted chalcone 3 was predicted theoretically by geometry optimization structure selected geometrical parameters and molecular properties such as NBO, AIM, HOMO-LUMO, MEP surface, and atomic charges were derived from optimized structures. The 1H and 13C NMR spectral data had been additionally computed using the Gaussian-09 package and compared with the experimental values. The antibacterial and antifungal activity was derived by the disc diffusion method.


2019 ◽  
Vol 9 (2) ◽  
pp. 409-416
Author(s):  
L. V. Domotenko ◽  
I. S. Kosilova ◽  
A. P. Shepelin

At present, a rise of antimicrobial resistance requires that susceptibility of infectious agents to antimicrobial agents could be accurately evaluated as related errors may lead to selecting improper therapeutics provoking spread of drug resistance. Pathogen sensitivity to antimicrobial agents is commonly determined by a disc diffusion method. A quality of nutrient medium used in assays plays a crucial role influencing final results. In Russia, it turned out that regulatory documents such as the nationwide guidelines and clinical recommendations outlining methodology for antimicrobial susceptibility testing underlay availability in domestic market few nutrient media, including Mueller–Hinton Agar, AGV medium etc. exhibiting sometimes unsatisfactory quality. To harmonize such methodology with international requirements, theStateResearchCenterfor Applied Microbiology and Biotechnology has developed a technology and promoted manufacture of Russia-made Mueller–Hinton agar satisfying requirements of EUCAST documents, clinical guidelines, and ISO/TS 16782:2016. The main objective of this study was to compare quality of new agar product with five similar foreign media while examining 11 test strains by disc diffusion method. As a result, some of nutrient media available to the Russian market turned out to be off-standard: not all of them satisfy to the EUCAST requirements and clinical guidelines since diameter distribution for growth inhibition recommended by EUCAST for quality control does not fit into permissible range. Moreover, susceptibility of P. aeruginosa ATCC 27853 to aminoglycosides, fluoroquinolones, Meropenem, as well as S. aureus ATSS 25923 and E. faecalis ATCC 29212 to tigecycline was assessed with certain mistakes. The data obtained by us were analyzed in accordance to the new document ISO/TS 16782:2016 “Clinical laboratory testing — criterion for acceptable lots of dehydrated Mueller–Hinton agar and broth for antimicrobial susceptibility testing”, not approved yet In Russia. To determine potential reason for deviation of data from reference range, we measured concentration of bivalent metals in all nutrient media examined by atomic emission spectrometry with inductively coupled plasma. We determined new patterns affecting reliability of results on microbial antibiotic susceptibility. A need to check intralaboratory quality control of nutrient media was emphasized.  


1999 ◽  
Vol 6 (3) ◽  
pp. 163-167 ◽  
Author(s):  
Bahri Ülküseven ◽  
Aydin Tavman ◽  
Gülten Ötük

The metal complexes of nine 2-substituted-1H-benzimidazoles (I-IX) with Ni(II), Pd(II), Cu(II), Ag(I), Zn(II) salts were synthesized. The compounds were characterized by melting point, analytical data, IR spectroscopy and magnetic susceptibility. The antimicrobial activity of the compounds was determined by the disk diffusion method in Mueller-Hinton Agar on Staphylococcus aureusATCC 6538, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Salmonella typhi, Shigella flexneri, Proteus mirabilis, Candida albicans ATCC 10231. Cu(II)and Ag(I)complexes of II, III and IV showed considerable activity against S. aureus, S. epidermidis, Ps. aeruginosa, S. typhi, Sh. flexneri and C. albicans microorganisms, the ligands themselves having no effect.


2018 ◽  
Vol 145 ◽  
pp. 140-153 ◽  
Author(s):  
Atta Ullah ◽  
Fatima Iftikhar ◽  
Muhammad Arfan ◽  
Syeda Tayyaba Batool Kazmi ◽  
Muhammad Naveed Anjum ◽  
...  

Author(s):  
Gaurab Risal ◽  
Aayush Shrestha ◽  
Saroj Kunwar ◽  
Gajal Paudel ◽  
Rameshwor Dhital ◽  
...  

Background: In urinary tract infections, an important role is played by bacterial biofilms which are responsible for persistence infections together with the antimicrobial resistance. Higher resistance can be seen in biofilm forming uropathogens in comparison with free-floating bacteria. So, the present study was performed with a goal to find the prevalence of biofilm formation and also the antimicrobial resistant pattern of uropathogens.Methods: A descriptive method was conducted at Modern Technical College, Sanepa, Lalitpur in samples isolated from UTI suspected patients. The overall duration of this study was approximately 3 months. Total of 50 isolated E. coli was tested for biofilm formation and antimicrobial susceptibility testing was done by Kirby-Bauer disc diffusion method on Mueller Hinton agar as per CLSI guidelines.Results: From the 50 isolates of E. coli, 32 were biofilm producers (3 strong and 29 moderate) and 18 were weak/non-biofilm producers. Among the biofilm producers, cefotaxime was more resistant in 20 of the isolates followed by ceftriaxone in 16 and amoxyclav in 13, whereas amikacin was least resistant in 2 of the isolates.Conclusions: Among the isolated E. coli, biofilm-forming isolates showed higher antimicrobial resistance as compared to the non-biofilm producer. Thus, uropathogen should be routinely screened for biofilm formation. 


2021 ◽  
Vol 10 (1) ◽  
pp. 16
Author(s):  
Saskia Arientika Wahyuningrum ◽  
Meiskha Bahar ◽  
Andri Pramesyanti Pramono

Pneumonia is a lung parenchymal infection caused by Pseudomonas aeruginosa.It is Gram negative bacteria that have developed antibiotic resistance. Actinomycetes are Gram-positive bacteria that produce secondary metabolites which have the ability as antimicrobial. Objectives: To identified the ability of Actinomycetes isolates to inhibit the growth of the bacterium Pseudomonas aeruginosa ATCC 27853. The samples in this experiment were from Kebun Raya Bogor that had been rejuvenated on Starch Casein Agar (SCA). Methods: Six dilution series 10-1; 10-2; 10-3; 10-4; 10-5; 10-6 Actinomycetes isolates were used to observe the inhibition zone of P.aeruginosa growth on Mueller Hinton Agar (MHA) media by diffusion method. Results: The effective incubation time occurred at 24 hours, and then it resulted in the average clear zone diameter of 14.70 mm, 10.57 mm, 8.53 mm, 8.47 mm, 6.97 mm, and 5.30 mm. The results of the One – Way Anova test with p-value = 0.000 (p < 0.005) showed some differences at each concentration to inhibit the growth of P.aeruginosa ATCC 27853 at 24 hours incubation period. Conclusion: The most effective concentration of Actinomycetes isolates that can potentially be antibacterial was the concentration of 10-1 with potential solid inhibitory power.Keywords: Actinomycetes, antibacterial, Pseudomonas aeruginosa


2020 ◽  
Vol 5 (2) ◽  
pp. 061-074
Author(s):  
Otajevwo Dafinone Festus ◽  
Osawaru Osama Emmanuella

The efficacy of Mueller Hinton agar over Nutrient agar in terms of antibiotic sensitivity testing for optimal antibiotic response by selected clinical bacterial pathogens was carried out in this study. Clinical bacterial pathogens used for the study were Pseudomonas aerµginosa, Enterococcus spp, Escherichia coli and Klebsiella pneumoniae. Standard and locally manufactured antibiotic discs used were by Abtek Biologicals Ltd, Liverpool and Maxicare Medical Laboratory, Nigeria respectively. Antibiotic sensitivity testing (AST) was by agar diffusion method. Pure cultures of each isolate were subcultured on sterile Mueller Hinton agar (MHA) and Nutrient agar (NA) media after which the standard and locally manufactured discs were aseptically impregnated on the media. All inoculated plates were incubated at 37oC for 24hrs aerobically after appropriate labeling. Zones of inhibition were measured by standard methods and recorded. On Nutrient agar, standard and locally produced ciprofloxacin, ofloxacin, gentamycin and amoxicillin/clavulanic acid discs did not produce zones of inhibition significantly different from each other at both 95% and 99% confidence intervals (P ˃ 0.05 and P ˃ 0.01). On Mueller Hinton agar, standard and locally manufactured ciprofloxacin, ofloxacin, gentamycin and amoxicillin/clavulanic acid discs produced zones of inhibition that were significantly different from each other at 95% confidence interval (P ˂ 0.05). Standard and local ciprofloxacin, ofloxacin, gentamycin and amoxicillin/clavulanic acid discs produced zones of inhibition on MHA and NA which were not significantly different (P ˃ 0.05 and P ˃ 0.01). Standard discs used recorded better zones of inhibition on MHA compared to the local discs. Standard and local discs zones of inhibition on MHA was however not significantly different from those recorded on NA (P ˃ 0.05). Standard discs therefore, did not produce better zones of inhibition over local discs on MHA and on NA. On the whole, the use of MHA for antibiotic sensitivity testing did not record greater (better) zones of inhibition than those recorded on NA except for standard ciprofloxacin, ofloxacin and gentamycin discs over the corresponding local discs on MHA only. Findings did not convincingly establish better performance of standard discs over local discs whether used on MHA or NA. Further studies in this direction is recommended.


Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 533
Author(s):  
Abdulmajeed S. H. Alsamarrai ◽  
Saba S. Abdulghani

A series of new acetamide derivatives 22–28 of primary and secondary amines and para-toluene sulphinate sodium salt have been synthesized under microwave irradiation and assessed in vitro for their antibacterial activity against one Gram-positive and two Gram-negative bacterial species such as S. pyogenes, E. coli, and P. mirabilis using the Mueller-Hinton Agar diffusion (well diffusion) method. The synthesized compounds with significant differences in inhibition diameters and MICs were compared with those of amoxicillin, ampicillin, cephalothin, azithromycin and doxycycline. All of the evaluated acetamide derivatives were used with varying inhibition concentrations of 6.25, 12.5, 37.5, 62.5, 87.5, 112.5 and 125 µg/mL. The results show that the most important antibacterial properties were displayed by the synthetic compounds 22 and 24, both of bear a para-chlorophenyl moiety incorporated into the 2-position moiety of acetamide 1. The molecular structures of the new compounds were determined using the FT-IR and 1H-NMR techniques.


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