Synthesis of some new 1-(5-((1H-pyrazol-1-yl)methyl)-2-aryl-1,3,4-oxadiazol-3(2H)-yl) ethanone derivatives and study their antimicrobial activity

Abstract Ethyl 2-(1H-pyrazol-1-yl)acetate (1) was synthesized by the reaction of ethylchloroacetate with 1H-pyrazole, Then compound (1) refluxed with hydrazine hydrate to get 2-(1H-pyrazol-1-yl) acetohydrazide (2). Compound (2) was reaction with appropriate aryl aldehyde to get schiff bases N'-arylidine-2-(1H-pyrazol-1-yl)acetohydrazide derivatives (3a-3f). schiff’s base (3a-3e) were cyclized by reflux with acetic anhydride to get new 1-(5-((1H-pyrazol-1-yl)methyl)-2-aryl-1,3,4-oxadiazol-3(2H)-yl)ethanone derivatives (4a-4e). The structures of the synthesized compounds were characterized by IR, 1H-NMR, 13C-NMR, mass spectra, and elemental analysis data. Synthesized compounds (4a-4e) were evaluated as antibacterial agents against some common pathogenic bacteria Gram-positive (Staphylococcus aureus, Streptococcus pyogenes) and Gram-negative bacteria (Escherichia coli, Psuedomonas aeruginosa). The result of antibacterial activity was compared with standard drugs (Ciprofloxacin and Tetracycline).

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Apomorphine Targets the Pleiotropic Bacterial Regulator Hfq

Antibiotics ◽

10.3390/antibiotics10030257 ◽

2021 ◽

Vol 10 (3) ◽

pp. 257

Author(s):

Florian Turbant ◽

David Partouche ◽

Omar El Hamoui ◽

Sylvain Trépout ◽

Théa Legoubey ◽

...

Keyword(s):

Small Rnas ◽

Antibacterial Agents ◽

Amyloid Fibrils ◽

Noncoding Rnas ◽

Amyloid Formation ◽

Gram Negative Bacteria ◽

Translation Efficiency ◽

Gram Negative ◽

Bacterial Adaptation ◽

E Coli

Hfq is a bacterial regulator with key roles in gene expression. The protein notably regulates translation efficiency and RNA decay in Gram-negative bacteria, thanks to its binding to small regulatory noncoding RNAs. This property is of primary importance for bacterial adaptation and survival in hosts. Small RNAs and Hfq are, for instance, involved in the response to antibiotics. Previous work has shown that the E. coli Hfq C-terminal region (Hfq-CTR) self-assembles into an amyloid structure. It was also demonstrated that the green tea compound EpiGallo Catechin Gallate (EGCG) binds to Hfq-CTR amyloid fibrils and remodels them into nonamyloid structures. Thus, compounds that target the amyloid region of Hfq may be used as antibacterial agents. Here, we show that another compound that inhibits amyloid formation, apomorphine, may also serve as a new antibacterial. Our results provide an alternative in order to repurpose apomorphine, commonly used in the treatment of Parkinson’s disease, as an antibiotic to block bacterial adaptation to treat infections.

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Effectiveness of Trisodium Phosphate, Acidified Sodium Chlorite, Citric Acid, and Peroxyacids against Pathogenic Bacteria on Poultry during Refrigerated Storage

Journal of Food Protection ◽

10.4315/0362-028x-70.9.2063 ◽

2007 ◽

Vol 70 (9) ◽

pp. 2063-2071 ◽

Cited By ~ 44

Author(s):

ELENA del RÍO ◽

REBECA MURIENTE ◽

MIGUEL PRIETO ◽

CARLOS ALONSO-CALLEJA ◽

ROSA CAPITA

Keyword(s):

Citric Acid ◽

Salmonella Enteritidis ◽

Pathogenic Bacteria ◽

Trisodium Phosphate ◽

Sodium Chlorite ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Microbial Group ◽

And Control

The effects of dipping treatments (15 min) in potable water or in solutions (wt/vol) of 12% trisodium phosphate (TSP), 1,200 ppm acidified sodium chlorite (ASC), 2% citric acid (CA), and 220 ppm peroxyacids (PA) on inoculated pathogenic bacteria (Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, Salmonella Enteritidis, Escherichia coli, and Yersinia enterocolitica) and skin pH were investigated throughout storage of chicken legs (days 0, 1, 3, and 5) at 3 ± 1°C. All chemical solutions reduced microbial populations (P < 0.001) as compared with the control (untreated) samples. Similar bacterial loads (P > 0.05) were observed on water-dipped and control legs. Type of treatment, microbial group, and sampling day influenced microbial counts (P < 0.001). Average reductions with regard to control samples were 0.28 to 2.41 log CFU/g with TSP, 0.33 to 3.15 log CFU/g with ASC, 0.82 to 1.97 log CFU/g with CA, and 0.07 to 0.96 log CFU/g with PA. Average reductions were lower (P < 0.001) for gram-positive (0.96 log CFU/g) than for gram-negative (1.33 log CFU/g) bacteria. CA and ASC were the most effective antimicrobial compounds against gram-positive and gram-negative bacteria, respectively. TSP was the second most effective compound for both bacterial groups. Average microbial reductions per gram of skin were 0.87 log CFU/g with TSP, 0.86 log CFU/g with ASC, 1.39 log CFU/g with CA, and 0.74 log CFU/g with PA for gram-positive bacteria, and 1.28 log CFU/g with TSP, 2.03 log CFU/g with ASC, 1.23 log CFU/g with CA, and 0.78 log CFU/g with PA for gram-negative bacteria. With only a few exceptions, microbial reductions in TSP- and ASC-treated samples decreased and those in samples treated with CA increased throughout storage. Samples treated with TSP and samples dipped in CA and ASC had the highest and lowest pH values, respectively, after treatment. The pH of the treated legs tended to return to normal (6.3 to 6.6) during storage. However, at the end of storage, the pH of legs treated with TSP remained higher and that of legs treated with CA remained lower than normal.

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Antimicrobial Activity of Gardenia jasminoides Callus and Crude Leaf Extracts for some Organic Solvents against some Pathogenic Bacteria and Yeasts

Journal of Biotechnology Research Center ◽

10.24126/jobrc.2014.8.3.355 ◽

2014 ◽

Vol 8 (3) ◽

pp. 40-45

Author(s):

Zina Hashem Shehab ◽

Huda Suhail Abid ◽

Sumaya Fadhil Hamad ◽

Sara Haitham

Keyword(s):

Staphylococcus Aureus ◽

Candida Albicans ◽

Pathogenic Bacteria ◽

Saccharomyces Boulardii ◽

Gram Negative Bacteria ◽

Proteus Vulgaris ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Gardenia Jasminoides

The study was conducted to evaluate the inhibitory activity of methanol extract of Gardenia jasminoides leaves compared with leaf crude extracts for some organic solvents namely Methanol, Ethanol, Petroleum ether, Asetone and Chloroform on growth of some pathogenic bacteria and yeast, which included four gram positive isolates Staphylococcus aureus, Enterococcus faecalis, Streptococcus pyogenes and Bacillus cereus and gram negative isolates Escherichia coli, Salmonella typhi, Proteus vulgaris and Pseudomonas aeruginosa and some yeasts Candida albicans and Saccharomyces boulardii, by using well diffusion method. The inhibitory activity of extracts in the tested bacterial strains and yeasts was varied according to the type of extracting solvents and are tested microorganisms. The methanol callus extract which grown on Murashige and Skoog (MS) media by using (Naphthalen acitic acid) NAA and (Benzyle adenine) BA as growth regulator highly effective as compared to the other extracts as for inhibition of three gram positive bacteria and three gram negative bacteria,which include Staphylococcus aureus and, Proteus vulgaris, followed by acetone and ethanolic extracts which include two gram positive bacteria and two gram negative bacteria. All extracts had highly effect in growth of Candida albicans while all crude extracts didn’t show any sensitivity against Saccharomyces boulardii, and when we’d done (High Performance Liquid Chromatography) HPLC test for detection of some active compound we found Quinic acid, Iridiods glycosides and Crocin which its rate in fresh callus was higher than fresh leaves.

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Antimicrobial Susceptibility Pattern of Gram-Negative Bacterial Isolates from Raw Chicken Meat Samples

Tribhuvan University Journal of Microbiology ◽

10.3126/tujm.v6i0.26590 ◽

2019 ◽

Vol 6 ◽

pp. 89-95

Author(s):

Neha Gautam ◽

Rojan Poudel ◽

Binod Lekhak ◽

Milan Kumar Upreti

Keyword(s):

Antimicrobial Resistance ◽

Pathogenic Bacteria ◽

Chicken Meat ◽

Food Microbiology ◽

Diffusion Method ◽

Resistance Pattern ◽

Kathmandu Valley ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Meat Samples

Objectives: This research aims to study the microbial quality of chicken meat available in retail shop of Kathmandu Valley. Methods: This Study was conducted from June to December 2018 in three different districts of Kathmandu Valley. Samples were collected in sterile plastic bags, labeled properly and stored in an icebox and transported to the Food Microbiology laboratory of Golden Gate International College. During sample preparation, 25 grams of each sample was taken and transferred to sterile flasks containing 225 ml of buffered peptone water. Potential pathogenic Gram-negative bacteria were isolated by using respective selective media and identified by biochemical test. Antibiotic susceptibility profile of isolates was carried out by Kirby-Bauer disc diffusion method according to CLSI 2017 guideline. Results: Of total 81 chicken meat samples processed; 201 Gram negative bacteria were isolated. E. coli (100%) was the dominant Gram-negative isolates, followed by Citrobacter spp (62.96%), Pseudomonas spp (40.74%), Proteus spp (19.75%), Salmonella spp (16.04%) and Klebsiella spp (8.64%) respectively. No any multidrug isolates were detected. Conclusion: The study showed that the raw chicken meat samples of Kathmandu valley was highly contaminated with Gram negative potential pathogenic bacteria. Antimicrobial resistance pattern shown by the isolates may indicates that there is not overuse of drug in animals and the less chance of risk of increasing antimicrobial resistance.

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Bacteriological Sampling of Telephones and Other Hospital Staff Hand-Contact Objects

Infection Control ◽

10.1017/s0195941700061051 ◽

1984 ◽

Vol 5 (11) ◽

pp. 533-535 ◽

Cited By ~ 13

Author(s):

Karen M. Rafferty ◽

Stephen J. Pancoast

Keyword(s):

General Hospital ◽

Acute Care ◽

Staff Member ◽

Pathogenic Bacteria ◽

Bacterial Contamination ◽

Hospital Staff ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Gram Negative Organisms ◽

Hand Contact

AbstractIn an acute-care general hospital, 114 telephones, intercoms, dictaphones, and bedpan flusher handles were sampled in patient-care areas for type of bacterial contamination. Nine of these (7%) demonstrated potentially pathogenic bacteria including Klebsiella, Enterobacter, Pseudomonas and Aeromonas. Inanimate, environmental, staff hand-contact objects were only lightly contaminated, did not represent a significant reservoir of gram-negative organisms, and therefore, would be unlikely to be a vehicle of transmission of gram-negative bacteria from the hands of one staff member to another under routine circumstances. Surveillance and disinfection of telephones and related hand-contact items in the hospital appear unnecessary.

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Antimicrobial effect of essential oils of some Fijian medicinal plant leaves on pathogenic bacteria

The South Pacific Journal of Natural and Applied Sciences ◽

10.1071/sp16005 ◽

2016 ◽

Vol 34 (2) ◽

pp. 35

Author(s):

Prayna P. P. Maharaj ◽

Riteshma Devi ◽

Surendra Prasad

Keyword(s):

Pseudomonas Aeruginosa ◽

Antimicrobial Agent ◽

Essential Oils ◽

Pathogenic Bacteria ◽

Antibacterial Properties ◽

Antimicrobial Activities ◽

Diffusion Method ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative

Fiji is highly populated with plants containing essential oils (EO). The essential oils extracted from the leaves of the selected Fijian leafy plants were screened against two Gram-negative bacteria (Salmonella typhimurium, Pseudomonas aeruginosa) and three Gram-positive bacteria (Staphylococcus aureus, Enterococcus faecalis and Bacillus subtilis). The agar diffusion method was used to examine the antimicrobial activities of the extracted EO. All the EO tested showed antibacterial properties against one or more strains while none of the EO was active against Pseudomonas aeruginosa. Viburnum lantana (Wayfaring tree), Annona muricata (Soursop), Coleus amboinicus (Spanish thyme) and Cinnamomum zeylancium (Cinnamon) showed good inhibition against both Gram-positive and Gram-negative bacteria and proved as worthy source of antimicrobial agent. These findings will help the Pacific population to use the studied plants leaves as antimicrobial agent.

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Bactericidal effects of non-thermal argon plasma in vitro, in biofilms and in the animal model of infected wounds

Journal of Medical Microbiology ◽

10.1099/jmm.0.020263-0 ◽

2011 ◽

Vol 60 (1) ◽

pp. 75-83 ◽

Cited By ~ 208

Author(s):

Svetlana A. Ermolaeva ◽

Alexander F. Varfolomeev ◽

Marina Yu. Chernukha ◽

Dmitry S. Yurov ◽

Mikhail M. Vasiliev ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Plasma Treatment ◽

Pathogenic Bacteria ◽

Argon Plasma ◽

Burkholderia Cenocepacia ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Plasma Treatments

Non-thermal (low-temperature) physical plasma is under intensive study as an alternative approach to control superficial wound and skin infections when the effectiveness of chemical agents is weak due to natural pathogen or biofilm resistance. The purpose of this study was to test the individual susceptibility of pathogenic bacteria to non-thermal argon plasma and to measure the effectiveness of plasma treatments against bacteria in biofilms and on wound surfaces. Overall, Gram-negative bacteria were more susceptible to plasma treatment than Gram-positive bacteria. For the Gram-negative bacteria Pseudomonas aeruginosa, Burkholderia cenocepacia and Escherichia coli, there were no survivors among the initial 105 c.f.u. after a 5 min plasma treatment. The susceptibility of Gram-positive bacteria was species- and strain-specific. Streptococcus pyogenes was the most resistant with 17 % survival of the initial 105 c.f.u. after a 5 min plasma treatment. Staphylococcus aureus had a strain-dependent resistance with 0 and 10 % survival from 105 c.f.u. of the Sa 78 and ATCC 6538 strains, respectively. Staphylococcus epidermidis and Enterococcus faecium had medium resistance. Non-ionized argon gas was not bactericidal. Biofilms partly protected bacteria, with the efficiency of protection dependent on biofilm thickness. Bacteria in deeper biofilm layers survived better after the plasma treatment. A rat model of a superficial slash wound infected with P. aeruginosa and the plasma-sensitive Staphylococcus aureus strain Sa 78 was used to assess the efficiency of argon plasma treatment. A 10 min treatment significantly reduced bacterial loads on the wound surface. A 5-day course of daily plasma treatments eliminated P. aeruginosa from the plasma-treated animals 2 days earlier than from the control ones. A statistically significant increase in the rate of wound closure was observed in plasma-treated animals after the third day of the course. Wound healing in plasma-treated animals slowed down after the course had been completed. Overall, the results show considerable potential for non-thermal argon plasma in eliminating pathogenic bacteria from biofilms and wound surfaces.

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One-step synthesis of amikacin modified fluorescent carbon dots for the detection of Gram-negative bacteria like Escherichia coli

RSC Advances ◽

10.1039/c6ra15778e ◽

2016 ◽

Vol 6 (76) ◽

pp. 72471-72478 ◽

Cited By ~ 19

Author(s):

Soumen Chandra ◽

Angshuman Ray Chowdhuri ◽

Triveni Kumar Mahto ◽

Arpita Samui ◽

Sumanta kumar Sahu

Keyword(s):

Escherichia Coli ◽

Carbon Dots ◽

Pathogenic Bacteria ◽

Gram Negative Bacteria ◽

Gram Negative ◽

One Step ◽

Fluorescent Carbon Dots ◽

Fluorescent Carbon

In this paper, we report a one-step strategy to synthesize amikacin modified fluorescent carbon dots (CDs@amikacin) for assaying pathogenic bacteria, Escherichia coli.

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Improving Antibacterial and Anti-biofilmic properties of urological catheters with Eucalyptus, Rosemary, Green tea and Ziziphora extracts by impregnation method

10.21203/rs.3.rs-280764/v1 ◽

2021 ◽

Author(s):

Najme Akhlaghi-Ardekani ◽

Davod Mohebbi-Kalhori ◽

Abdolreza samimi ◽

Reza Karazhyan

Keyword(s):

Green Tea ◽

Biofilm Formation ◽

Antibacterial Agents ◽

Antibacterial Properties ◽

Polymer Materials ◽

Gram Negative Bacteria ◽

Impregnation Method ◽

Herbal Extracts ◽

Urinary Catheters ◽

Gram Negative

Abstract The main complications of urinary catheters are the bacteria's biofilm formation and the urinary tract infection caused by gram-positive and gram-negative bacteria. In the recent years, the attention has changed its direction toward the antimicrobial, anti-biofilmic, and hydrophobicity effects of herbal extracts. Some of these extracts can inhibit the colonization of the two bacteria Staphylococcus aureus and Escherichia coli which are resistant to antibiotics. These bacteria can stick to the surface of polymer materials due to their hydrophobicity. Thus, antibacterial hydrophilic herbal extracts are supposed to help reduce the risk of the surficial infection if they are used to impregnate the urinary catheters. In this research, the extracts of these four plants eucalyptus, rosemary, green tea and ziziphora were used as the antibacterial agents. After the impregnation and modification of the sample catheters, they were tested by AFM, FE-SEM, ATR-FTIR methods to measure their mechanical, chemical, and hydrophilic properties, during the 21-day experiment period, compared to non-impregnated ones. The tests showed the silicone catheters impregnated by the herbal extracts have some significant anti-biofilmic and antibacterial properties (P˂0.0001) due to the increase in their hydrophilic property. The impregnated catheters could be release the extracts and killed bacteria in 21 days Therefore; some herbal extracts can be good alternatives to chemical drugs.

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The Hitchhiker’s Guide to the Periplasm: Unexpected Molecular Interactions of Antibiotics Revealed by Considering Crowding Effects in E. coli

10.1101/2020.06.03.132118 ◽

2020 ◽

Author(s):

Conrado Pedebos ◽

Iain P. S. Smith ◽

Alister Boags ◽

Syma Khalid

Keyword(s):

Molecular Dynamics ◽

Antibacterial Agents ◽

Gram Negative Bacteria ◽

Gram Negative ◽

E Coli ◽

Crowding Effects ◽

Therapeutic Mechanism ◽

Target Membrane ◽

Dynamics Simulations ◽

Crowded Environment

AbstractThe periplasm of Gram-negative bacteria is a highly crowded environment comprised of many different molecular species. Antibacterial agents that causes lysis of Gram-negative bacteria by their action against the inner membrane must cross the periplasm to arrive at their target membrane. Very little is currently known about their route through the periplasm, and the interactions they experience. To this end, here atomistic molecular dynamics simulations are used to study the path taken by the antibiotic polymyxin B1 through a number of models of the periplasm which are crowded with proteins and osmolytes to different extents. The simulations reveal that PMB1 forms transient and long-lived interactions with proteins and osmolytes that are free in solution as well as lipoproteins anchored to the outer membrane and bound to the cell wall. We show that PMB1 may be able to ‘hitchhike’ within the periplasm by binding to lipoprotein carriers. Overall our results show that PMB1 is rarely uncomplexed within the periplasm; an important consideration for interpretations of its therapeutic mechanism of action. It is likely that this observation can be extended to other antibiotics that rely on diffusion to cross the periplasm.

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