scholarly journals Synthesis, Molecular Docking, and Biofilm Formation Inhibitory Activity of Bis(Indolyl)Pyridines Analogues of the Marine Alkaloid Nortopsentin

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4112
Author(s):  
Heba M. Abo-Salem ◽  
Hayam A. Abd El Salam ◽  
Anhar M. Abdel-Aziem ◽  
Mohamed S. Abdel-Aziz ◽  
Eslam Reda El-Sawy
Keyword(s):  
Biofilm Formation ◽  
Ammonium Acetate ◽  
Binding Energies ◽  
Bacterial Strains ◽  
Topoisomerase Iv ◽  
Gram Positive ◽  
One Pot ◽  
Gram Negative ◽  
E Coli ◽  
Marine Alkaloid

An efficient and simple protocol for the synthesis of a new class of diverse bis(indolyl)pyridines analogues of the marine alkaloid nortopsentin has been reported. A one-pot four-component condensation of 3-cyanocarbomethylindole, various aldehyde, 3-acetylindole, and ammonium acetate in glacial acetic acid led to the formation of 2,6-bis(1H-indol-3-yl)-4-(substituted-phenyl)pyridine-5-carbonitriles. Additionally, 2,6-bis(1H-indol-3-yl)-4-(benzofuran) pyridine-5-carbonitriles were prepared via a one-pot four-component condensation of 3-cyanocarbomethylindole, various N-substituted-indole-3-aldehydes, 2-acetylbenzofuran, and ammonium acetate. The synthesized compounds were evaluated for their ability to inhibit biofilm formation against the Gram-positive bacterial reference strains Staphylococcus aureus ATCC 6538 and the Gram-negative strain Escherichia coli ATCC 25922. Some of the new compounds showed a marked selectivity against the Gram-positive and Gram-negative strains. Remarkably, five compounds 4b, 7a, 7c, 7d and 8e demonstrated good antibiofilm formation against S. aureus and E. coli. On the other hand, the release of reducing sugars and proteins from the treated bacterial strains over the untreated strains was considered to explain the disruption effect of the selected compound on the contact cells of S. aureus and E. coli. Out of all studied compounds, the binding energies and binding mode of bis-indole derivatives 7c and 7d were theoretically the best thymidylate kinase, DNA gyrase B and DNA topoisomerase IV subunit B inhibitors.

scholarly journals Design, Synthesis, and Antibacterial Screening of Some Novel Heteroaryl-Based Ciprofloxacin Derivatives as DNA Gyrase and Topoisomerase IV Inhibitors

2021 ◽  
Vol 14 (5) ◽  
pp. 399
Author(s):  
Lamya H. Al-Wahaibi ◽  
Amer A. Amer ◽  
Adel A. Marzouk ◽  
Hesham A.M. Gomaa ◽  
Bahaa G. M. Youssif ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Dna Gyrase ◽  
Bacterial Strains ◽  
Topoisomerase Iv ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Antibacterial Screening ◽  
Ic50 Values

A novel series of ciprofloxacin hybrids comprising various heterocycle derivatives has been synthesized and structurally elucidated using 1H NMR, 13C NMR, and elementary analyses. Using ciprofloxacin as a reference, compounds 1–21 were screened in vitro against Gram-positive bacterial strains such as Staphylococcus aureus and Bacillus subtilis and Gram-negative strains such as Escherichia coli and Pseudomonas aeruginosa. As a result, many of the compounds examined had antibacterial activity equivalent to ciprofloxacin against test bacteria. Compounds 2–6, oxadiazole derivatives, were found to have antibacterial activity that was 88 to 120% that of ciprofloxacin against Gram-positive and Gram-negative bacteria. The findings showed that none of the compounds tested had antifungal activity against Aspergillus flavus, but did have poor activity against Candida albicans, ranging from 23% to 33% of fluconazole, with compound 3 being the most active (33% of fluconazole). The most potent compounds, 3, 4, 5, and 6, displayed an IC50 of 86, 42, 92, and 180 nM against E. coli DNA gyrase, respectively (novobiocin, IC50 = 170 nM). Compounds 4, 5, and 6 showed IC50 values (1.47, 6.80, and 8.92 µM, respectively) against E. coli topo IV in comparison to novobiocin (IC50 = 11 µM).

Evolution of Our Experience in Diagnosis and Therapy for Urinary Infections

2009 ◽  
Vol 76 (2) ◽  
pp. 140-143
Author(s):  
R. Pizzorno ◽  
A. Simonato ◽  
M. Esposito ◽  
T. Montanaro ◽  
M. Mussap ◽  
...  
Keyword(s):  
Enterococcus Faecalis ◽  
Empirical Therapy ◽  
Enterococcus Species ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Diagnosis And Therapy ◽  
Urinary Infections ◽  
Spectrum Activity

The therapy for urinary infections is advised according to the antibiogram; the symptoms request an empirical therapy based on urinary infections knowledge and drugs spectrum activity. We considered the urinoculture performed on 3834 patients, 3012 male and 822 female, hospitalized in our Institute in the period between 01/01/2005 and 31/10/2006; 444 of these were positive (12.7 % - 451 bacterial strains). Table 1: bacterial strains isolaed. We reported some evaluations obtained by antibiogram. E. coli strains Ciprofloxacin sensitive resulted in 60% of cases. Enterococcus species and Enterococcus faecalis strains Ampicillin sensitive resulted in 96.4% and 100% of cases, respectively. In this study there is a Gram negative prevalence, whereas we had previously observed an equivalence between Gram negative and Gram positive (p 0.001). These data are useful for empirical therapy.

scholarly journals Spectral Studies and Antibacterial Activity of Vanadium(III) Complexes of Heterocyclic Hydrazones

2020 ◽  
Vol 32 (5) ◽  
pp. 1059-1063
Author(s):  
D. Kasimbi ◽  
K. Hussain Reddy ◽  
N. Devanna
Keyword(s):  
Analytical Techniques ◽  
Spectral Studies ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Tridentate Ligands ◽  
Structure Comparison ◽  
Gram Negative ◽  
E Coli ◽  
Physico Chemical ◽  
Uv Visible

Vanadium(III) complexes having the composition VLCl3 [where L = 2-acetylpyridine acetoylhydrazone (APAH), 2-acetylpyridine benzoylhydrazone (APBH), 2-acetylthiophene acetoylhydrazone (ATAH) and 2-acetylthiophene benzoylhydrazone (ATBH)] have been investigated using physico-chemical and analytical techniques. Molar conductivity data suggested that the complexes are neutral. Structures of all the vanadium(III) complexes are determined based on infrared and UV-visible spectral data. Electronic spectra of vanadium(III) complexes show three peaks suggesting octahedral structure. Comparison of vibrational spectra of hydrazones and complexes suggest that the hydrazones act as neutral tridentate ligands. The ligands and their vanadium derivatives are screened for their bacteria destroying activity against pathogenic bacterial strains viz. Gram-negative E. coli, Gram-positive Bacillus, Gram-positive Staphylococcus aureus and Gram-negative P. aureoginosa. Bacteria destroying activities of present complexes are comparable to the activity of the streptomycin. Complexes show more activity than their respective ligands in the case of Gram-positive Bacillus and Gram-negative P. aureoginosa.

scholarly journals Synthesis and Antimicrobial Evaluations of Sulfur Inserted Fluoro-Benzimidazoles

2021 ◽  
Vol 33 (7) ◽  
pp. 1525-1529
Author(s):  
Parmesh Kumar Dwivedi ◽  
Devdutt Chaturvedi
Keyword(s):  
Antimicrobial Agents ◽  
Bacterial Strains ◽  
Substituted Anilines ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
New Compounds ◽  
Derivatives Of ◽  
Multiple Step

A new series of fluorinated sulfur inserted benzimidazole analogues Za-i were synthesized and characterized. The new compounds were screened for their antimicrobial and antioxidant potential. The synthesized compounds were obtained by multiple step synthesis, initiating from the synthesis of 5-(difluoromethoxy)-1H-benzimidazole-2-thiol X. The compounds Ya-i prepared by reacting differently substituted anilines with chloroacetylchloride and triethylamine in DMF. Finally, the compound X was reacted with different derivatives of 2-chloro-N-phenylacetamide resulting in formation of titled compounds Za-i. The synthesized compounds (Za-Zi) were characterized by spectral analysis viz.1H & 13C NMR, mass spectra, elemental analysis and IR. The in vitro antimicrobial potential against Gram-positive (S. aureus and E. faecalis) and Gram-negative bacterial (E. coli and P.aeruginosa) strains as well as fungi (A. niger and C. albicans) was recorded for the obtained compounds. Some of the compounds exhibited encouraging results (in MIC) against Gram-positive and Gram-negative bacterial strains. These studies thus suggest that the designed sulfur inserted fluoro-benzimidazoles scaffold may serve as new promising template for further amplification as antimicrobial agents.

scholarly journals Pattern of Cytokine Responses to Gram-Positive and Gram-Negative Commensal Bacteria Is Profoundly Changed when Monocytes Differentiate into Dendritic Cells

2004 ◽  
Vol 72 (5) ◽  
pp. 2671-2678 ◽  
Author(s):  
Helen Karlsson ◽  
Pia Larsson ◽  
Agnes E. Wold ◽  
Anna Rudin
Keyword(s):  
Dendritic Cells ◽  
Bacterial Flora ◽  
Surface Expression ◽  
Commensal Bacteria ◽  
Enzyme Linked Immunosorbent Assay ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Bifidobacterium Adolescentis ◽  
Gram Negative ◽  
E Coli

ABSTRACT The normal gastrointestinal bacterial flora is crucial for the maturation of acquired immunity via effects on antigen-presenting cells (APCs). Here we investigated how two types of APCs, monocytes and dendritic cells (DCs), react to different bacterial strains typical of the commensal intestinal microflora. Purified human monocytes and monocyte-derived DCs were stimulated with UV-inactivated gram-positive (Lactobacillus plantarum and Bifidobacterium adolescentis) and gram-negative (Escherichia coli and Veillonella parvula) bacterial strains. Monocytes produced higher levels of interleukin 12p70 (IL-12p70) and tumor necrosis factor (TNF), as detected by an enzyme-linked immunosorbent assay, in response to L. plantarum than in response to E. coli and V. parvula. In contrast, DCs secreted large amounts of IL-12p70, TNF, IL-6, and IL-10 in response to E. coli and V. parvula but were practically unresponsive to L. plantarum and B. adolescentis. The lack of a response to the gram-positive strains correlated with lower surface expression of Toll-like receptor 2 (TLR2) on DCs than on monocytes. The surface expression of TLR4 on DCs was undetectable when it was analyzed by flow cytometry, but blocking this receptor decreased the TNF production in response to V. parvula, indicating that TLR4 is expressed at a low density on DCs. Gamma interferon increased the expression of TLR4 on DCs and also potentiated the cytokine response to the gram-negative strains. Our results indicate that when monocytes differentiate into DCs, their ability to respond to different commensal bacteria dramatically changes, and they become unresponsive to probiotic gram-positive bacteria. These results may have important implications for the abilities of different groups of commensal bacteria to regulate mucosal and systemic immunity.

scholarly journals Antibacterial Activity of Floral Petals of Some Angiosperms

2019 ◽  
pp. 1-5 ◽  
Author(s):  
L. Rajanna ◽  
N. Santhosh Kumar ◽  
N. S. Suresha ◽  
S. Lavanya
Keyword(s):  
Antibacterial Activity ◽  
Pathogenic Bacteria ◽  
Inhibition Zone ◽  
Bacterial Strains ◽  
Inhibitory Zone ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Antibacterial Assay

The in vitro antibacterial assay was carried out against both Gram positive (B. cerus and S. aureus) and Gram negative (E. coli and K. pneumoniae) bacteria. Floral petals of 20 different species of plants were collected and tested for antibacterial activity. The result showed that the petals were active against both Gram positive and Gram negative. Out of 20 floral petals tested, 19 floral petals exhibited antibacterial activity against selected bacterial strains. The minimal inhibitory zone of floral petal discs against human pathogenic bacteria varies from 2 – 6 mm. Rosa carolina and Ruellia tuberosa showed significance inhibition zone for all the bacterial strains while Lantana camara does not show inhibition zone for any of these pathogenic bacteria.

scholarly journals In Vitro, Controlling the Establishment of Xanthomonas Campestris with different Bacterial Bioagents

2016 ◽  
Vol 29 (1) ◽  
pp. 37-40
Author(s):  
Amna Ali ◽  
M Saleem Haider ◽  
Sobia Mushtaq ◽  
Ibatsam Khokhar ◽  
Irum Mukhtar ◽  
...  
Keyword(s):  
Xanthomonas Campestris ◽  
Fruits And Vegetables ◽  
Antimicrobial Agents ◽  
Bacterial Species ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Diffusion Technique

The antimicrobial agents of bacteria isolated from different rhizosphere of fruits and vegetables soil in Lahore. Of ten species, five were gram-negative (Escherichia coli, Pseudomonas fluorescence, Klebsiella pneumoniae, Salmonella typhii, Brachybacterium faecium); other five were gram positive and identified as Bacillus farraginis, Kurthia gibsonii, Aureobacterium liquefaciens, Curtobacterium albidum, Micrococcus lylae. The antagonistic potential of bacterial strains was assessed by the well diffusion technique and results indicating varying degree of biocontrol activity against pathogenic strain of X. campestris. Out of ten bacterial species, E. coli (gram negative) and C. albidum (gram positive) showed a high prevalence of resistance with reduction of 4.2cm and 4.1cm zone diameter respectively. The minimum inhibitory volume (MIV) to two bio-agents was determined for X. campestris from range 10-100 ?L. E. coli (volume required to inhibit < 20 ?L) and C. albidum (volume required to inhibit < 40 ?L) exhibited good activity against pathogen. These results provide information on the prevalence of resistant bacterial strains with the MIV of organisms and indicate the possibility of using these bacterial species as bio-agent against X. campestris.Bangladesh J Microbiol, Volume 29, Number 1, June 2012, pp 37-40

scholarly journals The spectrum of antibacterial activity of human defensins and cathelicidin against gram-positive and gram-negative bacterial strains isolated from hospitalized patients

2020 ◽  
Author(s):  
Albert Bolatchiev
Keyword(s):  
Antibacterial Activity ◽  
Synergistic Effect ◽  
Hospitalized Patients ◽  
New Drugs ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Conventional Antibiotics ◽  
Human Defensins

AbstractBackgroundTo date, there is a spread of resistance of microorganisms to antibiotics. To solve this problem, the search and development of new drugs with antibacterial activity is necessary. Antimicrobial peptides (AMPs) have pronounced antibacterial activity and may be promising candidates for the role of new drugs. Besides, AMPs can be used to overcome conventional antibiotics resistance due to the possible synergistic effect. In this work, the combined effect of some AMPs (human defensins, HNP-1, hBD-1, hBD-3 and cathelicidin, LL-37) with conventional antibiotics (vancomycin and imipenem) against gram-positive (Enterococcus faecalis; Staphylococcus aureus, methicillin-sensitive, MSSA, and methicillin-resistant, MRSA) and gram-negative (Escherichia coli; Klebsiella pneumoniae; Pseudomonas aeruginosa) bacterial strains was investigated.MethodsBacterial strains were isolated from hospitalized patients of the intensive care unit. Commercially available AMPs (HNP-1, hBD-1, hBD-3, LL-37 by Cloud-Clone Corp., USA) and antibiotics, vancomycin (Sandoz, Slovenia) and imipenem (Merck Sharp and Dohme, USA) were used. Antibiotic resistance phenotypes of isolated bacterial strains were carried out using the disk diffusion method. The standard checkerboard assays were used to study minimum inhibitory concentrations (MIC) of antimicrobials. The combined microbicidal effect of two substances (AMP+conventional antibiotic) was assessed by the fractional inhibitory concentration index (FICI). If FICI ≤ 0,5, then it was considered that two substances showed synergism of action; if 0.5 < FICI < 4 – no interaction; if FICI > 4 – antagonism.ResultsAll studied AMPs had antibacterial activity against the studied strains. hBD-3 showed the lowest MICs compared to other AMPs. MIC of hBD-3 against S. aureus (MSSA and MRSA), E. coli, K. pneumoniae was the same – 0.5 mg/L, and against P. aeruginosa it was 2 mg/L. The combinations HNP-1+vancomycin (against E. faecalis) and hBD-3+imipenem (against E. coli, K. pneumoniae, P. aeruginosa) according to FICI values have shown the synergistic effect. The results of this study can be used to develop novel antibiotics based on AMPs. Also, in some cases, AMPs can help to overcome resistance to conventional antibiotics.

scholarly journals Synthesis and antimicrobial activity of some new N-(aryl-oxo-alkyl)-5-arylidene-thiazolidine-2,4-diones

2014 ◽  
Vol 79 (2) ◽  
pp. 115-123 ◽  
Author(s):  
Anca Stana ◽  
Brînduşa Tiperciuc ◽  
Mihaela Duma ◽  
Adrian Pîrnău ◽  
Philippe Verité ◽  
...  
Keyword(s):  
Antimicrobial Activities ◽  
Fungal Strain ◽  
Gram Negative Bacteria ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Reference Drug ◽  
Gram Negative ◽  
E Coli ◽  
Inhibitory Activities

A series of new 5-(2,6-dichlorobenzylidene)thiazolidine-2,4-dione and 5-(4-methoxy-benzylidene)thiazolidine-2,4-dione derivatives (3a-h and 5a-h) were synthesized starting from 5-arylidene-thiazolidine-2,4-dione and ?-halo-ketones. The structural elucidation of the newly synthesized compounds was based on elemental analysis and spectroscopic data (MS, 1H-NMR, 13C-NMR). The synthesized compounds were screened for their antimicrobial activities against several pathogenic strains of Gram-positive and Gram-negative bacteria and one fungal strain (Candida albicans), assessed in vitro as growth inhibition diameters. Some of them displayed better inhibitory activities than that of the reference drug against the Gram-positive S. aureus, B. cereus, L. monocytogenes bacterial strains, and showed good antifungal activity against C. albicans, while the antibacterial activity against Gram-negative E. coli and S. typhimurium bacterial strains was moderate.

SYNTHESIS AND EVALUATION OF ANTIBACTERIAL, ANTHELMINTIC ACTIVITIES OF SUBSTITUTED BENZIMIDAZOLE DERIVATIVES

INDIAN DRUGS ◽  
2017 ◽  
Vol 54 (06) ◽  
pp. 69-76
Author(s):  
D Sharma ◽  
◽  
G. K Sharma ◽  
D. Pathak ◽  
M. C. Sharma
Keyword(s):  
Antibacterial Activity ◽  
Anthelmintic Activity ◽  
Benzimidazole Derivatives ◽  
The Novel ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Alkyl Aryl ◽  
Gram Negative ◽  
E Coli

The study was undertaken to synthesize and evaluate antibacterial, anthelmintic activities of N’ (substituted benzylidene)-2-(2-alkyl/aryl-1H-benzo[d] imidazole-1yl) acetohydrazide derivatives. All the novel benzimidazole derivatives were screened for anthelmintic activity against Pherituma posthuma species of earthworms and antibacterial activity against following bacterial strains: S. aureus, B.subtilis (Gram positive) and E. coli and P.aeruginosa (Gram negative). The antibacterial data suggest that compounds having nitro and hydroxyl substitution were more potent and the anthelmintic data suggest that compounds having chloro were most active.

Sign in / Sign up

Export Citation Format

Share Document