scholarly journals The In Vitro Anti-Pseudomonal Activity of Cu2+, Strawberry Furanone, Gentamicin, and Lytic Phages Alone and in Combination: Pros and Cons

2021 ◽  
Vol 22 (18) ◽  
pp. 9830
Author(s):  
Agata Dorotkiewicz-Jach ◽  
Pawel Markwitz ◽  
Zuzanna Drulis-Kawa
Keyword(s):  
Antibacterial Agents ◽  
Inhibitory Concentration ◽  
Antibacterial Effect ◽  
Toxic Metal ◽  
Protein Synthesis Inhibition ◽  
Progeny Production ◽  
Protein Inactivation ◽  
Pros And Cons ◽  
Cell Membrane Disruption

In this study, we investigated the anti-pseudomonal activity of cupric ions (Cu2+), strawberry furanone (HDMF), gentamicin (GE), and three lytic Pseudomonas aeruginosa bacteriophages (KT28, KTN4, LUZ19), separately and in combination. HDMF showed an anti-virulent effect but only when applied with Cu2+ or GE. GE, at a sub-minimal inhibitory concentration, slowed down phage progeny production due to protein synthesis inhibition. Cu2+ significantly reduced both the bacterial cell count and the number of infective phage particles, likely due to its genotoxicity or protein inactivation and cell membrane disruption effects. Furthermore, Cu2+‘s probable sequestration by phage particles led to the reduction of free toxic metal ions available in the solution. An additive antibacterial effect was only observed for the combination of GE and Cu2+, potentially due to enhanced ROS production or to outer membrane permeabilization. This study indicates that possible interference between antibacterial agents needs to be carefully investigated for the preparation of effective therapeutic cocktails.

scholarly journals ESTIMATION THE ANTIBACTERIAL EFFECT OF CURCUMIN AND ROSEMARY AMONG PATIENTS WITH DENTAL CARIES IN VITRO

2019 ◽  
pp. 277-279
Author(s):  
EHAN ABDULHADI AL-SHARIFI ◽  
ASIA ABED AL-MAHMOOD ◽  
SUMAYAH AL-MAHMOOD
Keyword(s):  
Dental Caries ◽  
Aqueous Extract ◽  
Antibacterial Agents ◽  
Bacterial Culture ◽  
Antibacterial Effect ◽  
Anaerobic Bacteria ◽  
Oral Bacteria ◽  
Mannitol Salt Agar ◽  
Inhibition Zones

Objective: The aim is to estimate the effect of curcumin and rosemary as antibacterial agents among dental caries cases. Methods: Samples of saliva were randomly collected from 40 patients in Al-Furat General Hospital who attended the hospital from July to September 2018. Swabs were cultured on blood agar at 37°C for 24 h and then subcultured in mannitol salt agar and trypticase soy broth at 37°C for 24 h. Different concentrations of aqueous extract curcumin solution (0.1, 0.3, 0.5, and 1 mg/ml) and rosemary solution (1 g/ml) were prepared and added to the bacterial culture. Later, minimum inhibition zones of the bacterial cultures were determined. Results: The results showed that there were 25 cases of Streptococcus mutans, 10 cases of Staphylococcus aureus, 3 cases of anaerobic bacteria, and 2 cases of normal flora among 40 culturing swabs of bacteria. Aqueous extract of curcumin showed antibacterial effect with concentrations (0.1, 0.3, 0.5, and 1 mg/ml) against oral bacteria; nevertheless, these bacteria were resistant to the aqueous extract of rosemary with concentration 1 g/ml. Conclusion: It can be concluded that curcumin can be an effective antibacterial agent against dental caries disease and its effect increases positively in relation to its concentration. On the other hand, rosemary with 1 g/ml concentration did not show any effect on oral bacteria.

scholarly journals Synthesis and in vitro Antibacterial Activity of Quaternization 10-Methoxycanthin-6-one Derivatives

2019 ◽  
Author(s):  
Na Li ◽  
Jiang-Kun Dai ◽  
Dan Liu ◽  
Jin-Yi Wang ◽  
Jun-Ru Wang
Keyword(s):  
Antibacterial Activity ◽  
Natural Products ◽  
Minimum Inhibitory Concentration ◽  
Pathogenic Bacteria ◽  
Antibacterial Agents ◽  
Inhibitory Concentration ◽  
Dilution Method ◽  
In Vitro Antibacterial Activity

Natural products are an important source of antibacterial agents. Canthin-6-one alkaloids have displayed potential antibacterial activity based on our previous work. In order to improve the activity, twenty-two new 3-N-benzylated 10-methoxy canthin-6-ones were designed and synthesized through quaternization reaction. The in vitro antibacterial activity against three bacteria was evaluated by double dilution method. Four compounds (6f, 6i, 6p and 6t) displayed 2-fold superiority (minimum inhibitory concentration (MIC) = 3.91 µg/mL) against agricultural pathogenic bacteria R. solanacearum and P. syringae than agrochemical propineb. Moreover, the structure–activity relationships (SARs) were also carefully summarized in order to guide the development of antibacterial canthin-6-one agents.

scholarly journals Effects of associations of tannins from Anacardium occidentale and Anadenanthera colubrina with cephalosporin against bovine Staphylococcus aureus isolates

2018 ◽  
Vol 85 (0) ◽  
Author(s):  
Andréia Vieira Pereira ◽  
Marcelo Biondaro Góis ◽  
Tatiane Kelly Barbosa Azevêdo ◽  
Fabiana Nabarro Ferraz ◽  
Suellen Laís Vicentino Vieira ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Drug Resistance ◽  
Inhibitory Concentration ◽  
Antibacterial Effect ◽  
Mechanisms Of Action ◽  
Anacardium Occidentale ◽  
Distilled Water ◽  
Conventional Antibiotics

ABSTRACT: The association of natural compounds isolated from medicinal plants with conventional antibiotics, both with similar mechanisms of action, have become a viable alternative strategy to overcome the problem of drug resistance. This study aimed to evaluate the in vitro antimicrobial activity of tannic substances present in the bark of Anacardium occidentale and Anadenanthera colubrina against samples of Staphylococcus aureus when in combination with cephalexin. These combinations were evaluated by determining the minimum inhibitory concentration (MIC). For this purpose, tannins and cephalexin were serially dissolved in distilled water at concentrations ranging from 0.976 mg/mL to 500 mg/mL and 2 mg/mL to 512 mg/mL, respectively. When combined, the compounds inhibited S. aureus growth forming halos ranging from 0.9 to 46 mm with an MIC of 7.8 mg/mL (tannins) and 4 µg/mL (cephalexin). The resulting effect of the combination of natural and synthetic substances with similar mechanisms of action presented better results than when tested alone. Thus, the conclusion is that both the tannins and cephalexin had their antimicrobial action enhanced when used in combination, enabling the use of lower concentrations while maintaining their antibacterial effect against strains of S. aureus.

scholarly journals Nanocluster Structure of Pistacia atlantica subsp. Kurdica Turpentine and Its Antibacterial Effects

2020 ◽  
Vol 18 ◽  
Author(s):  
Ramyar Rahimi Darehbagh ◽  
Rojin Ramezani ◽  
Afra Hosseinpanahi ◽  
Ahmad Fotoohi ◽  
Samaneh Rouhi
Keyword(s):  
Antibacterial Agents ◽  
Direct Relationship ◽  
Antibacterial Effect ◽  
Inhibition Zone ◽  
In Vivo Studies ◽  
Antibacterial Effects ◽  
Pistacia Atlantica ◽  
Inhibition Zones

Background: Medicinal herbs such as Pistacia atlantica (P. atlantica) subsp. Kurdica have antimicrobial effects. The present study is aimed to investigate the nanocluster structure of P. atlantica subsp. Kurdica turpentine and its composing elements and antibacterial effect. Methods: 100 μl ethanol was used to dissolve oily turpentine. 2, 2.2, 2.4, and 2.6 µg/μl of turpentine were used for investigating the antibacterial effects using disk and well diffusion methods. Elemental and nanocluster structure analyses were performed by Energy-Dispersive XRay Microanalysis (EDXMA) and Field Emission (FE)-scanning electron. Two-way analysis of variance (ANOVA) and Bonferoni test were used for data analysis (p ≤ 0.001). Results and Discussion: EDXMA elemental analysis of turpentine included: zinc (Zn), magnesium (Mg), fluorine (F), oxygen (O), silicium (Si), carbon (C), and argentum (Ag). A topography image of the turpentine showed a nanocluster surface with bright clusters in the background. The largest diameters of the growth inhibition zones (24.67 ± 0.58 mm in the disk diffusion and 23.67 ± 1.53 mm in the well diffusion) that were created by turpentine were observed against S. aureus ATCC 25923 at the concentration of 2.6 µg/μl. Diameter of the inhibition zone around bacterial growth had a direct relationship with turpentine concentration (p ≤ 0.001). Conclusion: The nanocluster structure of turpentine and its composed elements were detected in this research. Moreover, antibacterial effects of turpentine were proved. Herbal substances are widely used in medical applications. Different elements of P. atlantica subsp. Kurdica turpentine can be used as antibacterial agents, but more in-vitro and in-vivo studies should be performed in this field.

scholarly journals In Vitro Activity of Antimicrobial Agents against Streptococcus Pyogenes Isolates from Patients with Acute Tonsillopharyngitis in Dakar, Senegal

2009 ◽  
Vol 2 ◽  
pp. MBI.S2319
Author(s):  
A. Gueye Ndiaye ◽  
ND.C. Sarr ◽  
K. Thiam ◽  
C.S. Boye
Keyword(s):  
High Activity ◽  
Streptococcus Pyogenes ◽  
Antibacterial Agents ◽  
Antimicrobial Agents ◽  
Inhibitory Concentration ◽  
Capital City ◽  
Beta Lactam ◽  
Beta Lactam Antibiotics ◽  
First Choice

Streptococcus pyogenes ( S. pyogenes) is the most important causative agent of tonsillopharyngitis. Beta-lactam antibiotics, particularly penicillin, are the drug of first choice and macrolides are recommended for patients who are allergic to penicillin. However, other antibiotics are also used for the treatment of streptococcal tonsillopharyngitis. In recent years, the increase in the incidence of respiratory tract pathogens that are resistant to current antibacterial agents highlights the need to monitor the evolution of the resistance of these pathogens to antibiotics. In this study, we assess the susceptibility of 98 isolates of S. pyogenes to 16 antibiotics. The pathogens were recovered from patients with acute tonsillopharyngitis in Dakar, the Senegalese capital city, who were recruited from May 2005 to August 2006. All strains were susceptible to penicillin with low Minimum Inhibitory Concentration (MIC = 0,016 mg/L). Amoxicillin had high activity (100%) showing its importance in treatment of streptococcal infections. Cephalosporins had MIC90 values ranging from 0.016 to 0.094 mg/L. Macrolides have shown high activity. All strains were resistant to tetracyclin. Other molecules such as teicoplanin, levofloxacin and chloramphenicol were also active and would represent alternatives to treatment of tonsillopharyngitis due to this pathogen. These results indicate that no significant resistance to antibiotics was found among patients with tonsillopharyngitis studied in Dakar. Limitations of this study were that the number of isolates tested was small and all isolates were collected from one hospital in Dakar. Hence, results may not be representative of the isolates found, in the wider community or other regions of Senegal. Further studies are needed in other parts of Dakar and other geographic regions of Senegal, in order to better clarify the antibiotic susceptibility profile of S. pyogenes isolates recovered from patients with tonsillopharyngitis.

scholarly journals In-vitro synergistic antibacterial effect of atorvastatin and ampicillin against resistant Staphylococcus spp and E.coli isolated from bovine mastitis

2019 ◽  
Author(s):  
Sriraam Sankar ◽  
Ramasamy Thangamalai ◽  
Sriram Padmanaban ◽  
Porteen Kannan ◽  
M R Srinivasan ◽  
...  
Keyword(s):  
Minimum Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Antibacterial Effect ◽  
Bovine Mastitis ◽  
Diffusion Method ◽  
Mannitol Salt Agar ◽  
E Coli ◽  
Antibiotic Drug ◽  
Staphylococcus Spp

AbstractThe colossal rise in antimicrobial resistance has led to treatment failures and so mastitis has become cumbersome to treat. The objective of this study was to evaluate the antibacterial effect of non-antibiotic drug, atorvastatin in combination with antimicrobial, ampicillin against two commonly isolated bacterial species Staphylococcus spp and E. coli from bovine mastitis. Milk samples were collected from mastitis cows, visiting Veterinary Clinical Complex. Bacterial isolation was performed using Eosin Methylene Blue (EMB) agar and Mannitol Salt Agar (MSA), followed by characterization and identification by biochemical tests and gram staining. Genotypic confirmation was done by Polymerase Chain Reaction (PCR) with subsequent screening for resistant genes-mec A, blaTEM. Antibiotic Sensitivity Test (ABST) of the isolates against 12 different antimicrobials, atorvastatin only, and combination of atorvastatin with ampicillin were performed using Kirby-Bauer disc diffusion method. Minimum Inhibitory Concentration (MIC) of ampicillin alone and ampicillin in combination with atorvastatin were determined by modified microdilution method. Staphylococcus spp (77.5%) and E.coli (35%) were the two major pathogens isolated in the current study and multi-drug resistance was observed. Among the antimicrobials, the ampicillin showed 100% resistance against Staphylococcus spp and 85.71% resistance against E. coli. Atorvastatin did not display antibacterial effect as a sole agent but displayed synergistic antibacterial activity with ampicillin. There was an average increase in Minimum Inhibitory Concentration of ampicillin for E.coli and Staphylococcus spp isolates and atorvastatin decreased the Minimum Inhibitory Concentration of ampicillin in combination. The ampicillin shows more resistance against both Staphylococcus spp and E.coli, while atorvastatin improves the effect of ampicillin in-vitro. So, atorvastatin may be combined with ampicillin for the treatment of Gram-positive and Gram-negative infections. However, further studies are required to ascertain the exact mechanism of action of atorvastatin with respect to their antibacterial effect for them to be redeployed as an antimicrobial drug in the future.

scholarly journals IN VITRO ANTIBACTERIAL ACTIVITY OF ROYAL GELLY AGAINST PATHOGEN ESCHERICHIA COLI

2018 ◽  
Vol 14 (1) ◽  
Author(s):  
D. Dinkov ◽  
D. Stratev ◽  
R. Balkanska
Keyword(s):  
Antibacterial Agents ◽  
Royal Jelly ◽  
Antibacterial Effect ◽  
Bacterial Suspension ◽  
E Coli ◽  
Before And After ◽  
In Vitro Antibacterial Activity ◽  
Almost All ◽  
Pathogen Strains

In the study was used a pathogen strain of E. coli, caused septicemia for ducks,resistant for different antibacterial agents: Amoxicillin, Lincospectin, Chloramphenicol,Doxycyclin, Enrofl oxacin, Sulfonamides and Trimetoprim. Bacterial suspension of E.coli icontaminated each from test solutions in TSB of royal jelly (n=6), mixes of royaljelly and rape honey, and independent used rape honey (10–45% v/v). Have in mindexactly counts of colonies before and after incubation from each of test substanceswas calculated the percent of reduction up to 30 min, and after incubation (24 hand 48 h). In almost all concentrations of royal jelly (10–45 v/v), were found totalinhibition effect to E. coli. Mixes from royal jelly and rape honey (1:100) possesseda higher antibacterial effect, compared with independent use of rape honey. Up to45% (v/v), rape honey does not cause total antibacterial reduction. Royal jelly andmixes from royal jelly and rape honey have potential as alternative therapeuticsagents against resistant for antibiotics pathogen strains of E. coli.

scholarly journals Thiocarbamates from Moringa oleifera Seeds Bioactive against Virulent and Multidrug-Resistant Vibrio Species

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Renata Albuquerque Costa ◽  
Oscarina Viana de Sousa ◽  
Ernesto Hofer ◽  
Jair Mafezoli ◽  
Francisco Geraldo Barbosa ◽  
...  
Keyword(s):  
Antibacterial Agents ◽  
Moringa Oleifera ◽  
Inhibitory Concentration ◽  
Alternative Therapy ◽  
Ethyl Acetate Fraction ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Ethanol Extracts ◽  
Seed Extracts

Prospect of antibacterial agents may provide an alternative therapy for diseases caused by multidrug-resistant bacteria. This study aimed to evaluate the in vitro bioactivity of Moringa oleifera seed extracts against 100 vibrios isolated from the marine shrimp Litopenaeus vannamei. Ethanol extracts at low (MOS-E) and hot (MOS-ES) temperature are shown to be bioactive against 92% and 90% of the strains, respectively. The most efficient Minimum Inhibitory Concentration (MIC) levels of MOS-E and MOS-ES against a high percentage of strains were 32 µg mL−1. Bioguided screening of bioactive compounds showed that the ethyl acetate fraction from both extracts was the only one that showed antibacterial activity. Vibriocidal substances, niazirine and niazimicine, were isolated from the aforementioned fraction through chromatographic fractionation.

scholarly journals Lauryl-poly-L-lysine: A New Antimicrobial Agent?

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Laetitia Vidal ◽  
Véronique Thuault ◽  
Arturo Mangas ◽  
Rafael Coveñas ◽  
Anne Thienpont ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Antibacterial Activity ◽  
Fatty Acid ◽  
Antimicrobial Agent ◽  
Inhibitory Concentration ◽  
Antibacterial Effect ◽  
Gram Negative Bacteria ◽  
Multiple Antibiotic Resistance ◽  
Good Ability

The development of multiple antibiotic resistance is a global problem. It is necessary to find new tools whose mechanisms of action differ from those of currently used antibiotics. It is known that fatty acids and cationic polypeptides are able to fight bacteria. Here, we describe the synthesis of fatty acids linked to a polypeptide with antibacterial activity. The linkage of fatty acids to a polypeptide is reported to increase the antibacterial effect of the linked fatty acid in comparison with free fatty acids (FA) or free poly-L-lysine (PLL) or a mixture of both (FA free + PLL free). A number of C6–C18 fatty acids were linked to PLL to obtain new synthetic products. These compounds were assessed in vitro to evaluate their antibacterial activity. Some fatty acid-PLLs showed a good ability to fight bacteria. Their bactericidal activity was evaluated, and, lauryl linked to PLL was found to be the most active product against both Gram-positive and Gram-negative bacteria. This new active component showed a good degree of specificity and reproducibility and its minimum inhibitory concentration (MIC) was comparatively good. The antibacterial activity of the lauryl-PLL compound suggests that it is a new and promising antimicrobial agent.

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