scholarly journals The Synergy and Mode of Action of Cyperus rotundus L. Extract Plus Ampicillin against Ampicillin-Resistant Staphylococcus aureus

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Prairadda Cheypratub ◽  
Wilairat Leeanansaksiri ◽  
Griangsak Eumkeb
Keyword(s):  
Staphylococcus Aureus ◽  
Concentration Index ◽  
Inhibitory Concentration ◽  
Cytoplasmic Membrane ◽  
Chemical Compounds ◽  
Cyperus Rotundus ◽  
Synergistic Activity ◽  
Electron Microscopic ◽  
Average Cell ◽  
Checkerboard Assay

Cyperus rotundus L. has been used for pharmaceutical applications including antibacterial infections. Nevertheless, there is still no data regarding the mode of actions. This study aimed to determine the antibacterial activity and mode of actions of Cyperus rotundus extract (CRE) against ampicillin-resistant Staphylococcus aureus (ARSA) which poses a serious problem for hospitalized patients. The majority of chemical compounds of CRE were flavonoids and alkaloids. The minimum inhibitory concentrations (MICs) for ampicillin and CRE against all ARSA strains were 64 μg/ml and 0.5 mg/ml, respectively. Checkerboard assay revealed synergistic activity in the combination of ampicillin and CRE at the lowest fractional inhibitory concentration index (FICI) at 0.27. The killing curve assay had confirmed the synergistic and bactericidal activity of the combination against ARSA. Electron microscopic results showed that these ARSA cells treated with this combination caused peptidoglycan and cytoplasmic membrane (CM) damage and average cell areas significantly smaller than control. Also, this combination caused an increase in CM permeability of ARSA. CRE revealed the inhibitory activity against β-lactamase. It is normally known that some drugs are derived from flavonoids or alkaloids. So, this CRE proposes the potential to develop a novel adjunct phytopharmaceutical to ampicillin for the remedy of ARSA.

scholarly journals A Pilot Study of the Synergy between Two Antimicrobial Peptides and Two Common Antibiotics

Antibiotics ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 60 ◽  
Author(s):  
Franziska Kampshoff ◽  
Mark D. P. Willcox ◽  
Debarun Dutta
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Agents ◽  
Inhibitory Concentration ◽  
Synergistic Activity ◽  
Fractional Inhibitory Concentration ◽  
First Line ◽  
Checkerboard Assay ◽  
Resistant Strains ◽  
And Staphylococcus Aureus ◽  
Broth Dilution

Background: Frequent and unrestricted use of antibiotics has been associated with the development of antibiotic resistance by microorganisms. Thus, there is a need to find novel antibacterial agents or a combination of agents as the first line of treatment for various infections. This study aimed to investigate the synergy between antimicrobial peptide (AMP) combinations or between AMP-antibiotics combinations using two common pathogens, Pseudomonas aeruginosa and Staphylococcus aureus. Methods: The AMPs melimine, Mel4 and protamine, and antibiotics cefepime and ciprofloxacin were used in this study. The minimum inhibitory concentration (MIC) of each were evaluated against P. aeruginosa and S. aureus strains by a microtiter broth dilution. Based on the MIC of each antimicrobial agent, a checkerboard assay was performed to investigate the synergy between them, which was expressed as the fractional inhibitory concentration (FIC). Results: The combination of melimine and ciprofloxacin showed synergistic activity against antibiotic sensitive or resistant strains of P. aeruginosa and with FIC values ≤0.5. Conclusion: Combinations of AMPs and the fluoroquinolone ciprofloxacin is a promising method for reducing resistance to the fluoroquinolone of P. aeruginosa.

scholarly journals Exebacase Demonstrates In Vitro Synergy with a Broad Range of Antibiotics against both Methicillin-Resistant and Methicillin-Susceptible Staphylococcus aureus

2019 ◽  
Vol 64 (2) ◽  
Author(s):  
Aubrey Watson ◽  
Karen Sauve ◽  
Cara Cassino ◽  
Raymond Schuch
Keyword(s):  
Staphylococcus Aureus ◽  
Concentration Index ◽  
Susceptibility Testing ◽  
Inhibitory Concentration ◽  
Antimicrobial Protein ◽  
Content Type ◽  
Fractional Inhibitory Concentration Index ◽  
Checkerboard Assay ◽  
Time Kill

ABSTRACT In vitro synergy between an antimicrobial protein lysin (cell wall hydrolase) called exebacase and each of 12 different antibiotics was examined against Staphylococcus aureus isolates using a nonstandard medium approved for exebacase susceptibility testing by the Clinical and Laboratory Standards Institute. In the checkerboard assay format, fractional inhibitory concentration index values of ≤0.5, consistent with synergy, were observed for the majority of interactions tested. Synergy was further confirmed in time-kill assays.

scholarly journals Effect the combination of antibiotics on clinical isolates of Staphylococcus aureus

2009 ◽  
Vol 6 (4) ◽  
pp. 683-692
Author(s):  
Baghdad Science Journal
Keyword(s):  
Staphylococcus Aureus ◽  
Concentration Index ◽  
Inhibitory Concentration ◽  
Morphological Characterization ◽  
Penicillin G ◽  
Clinical Samples ◽  
Fractional Inhibitory Concentration ◽  
Fractional Inhibitory Concentration Index ◽  
Lactam Antibiotic ◽  
Susceptibility Tests

Atotal of 75 different clinical samples were collected from different hospitals in Baghdad Biochemical and morphological characterization tests showed that forty isolates were identified as Staphylococcus aureus Antibiotic susceptibility tests of all isolates towards ten antibiotics were carried out and results showed that many isolates (97.5 %) were resistant to ?-lactam antibiotic , 70 % were resistant to Tetracyclinee , 62.5% were resistant to co-trimoxazole , 60 % were resistant to ciprofloxacin , 55% were resistant both of chloramphenicol and erythromycin , 52.5% were resistant to gentamicin , 35% were resistant to rifampicin , 10% were resistant to vancomycin . According to the above results the S.aureus I1 which is isolated from patients with osteomyelitis showed resistant to all ten antibiotics therefore was used in the followed experiments. The minimum inhibitory concentration (MIC) of S.aureus I1 vancomycin, cefotaxim , penicillin G, amoxicillin , ciprofloxacin , co-trimoxazole ,gentamicin, rifampicin was checked.The results showed that isolates had MIC between (390-12500) ?g/ml. The combination of different antibiotics with vancomycin showed synergistic effect based on the Fractional inhibitory concentration index (FIC).

scholarly journals Antibacterial Activity of Geraniol in Combination with Standard Antibiotics against Staphylococcus aureus, Escherichia coli and Helicobacter pylori

2018 ◽  
Vol 13 (7) ◽  
pp. 1934578X1801300 ◽  
Author(s):  
Subrat Kumar Bhattamisra ◽  
Chew Hui Kuean ◽  
Lee Boon Chieh ◽  
Vivian Lee Yean Yan ◽  
Chin Koh Lee ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Helicobacter Pylori ◽  
Antibacterial Activity ◽  
Synergistic Effect ◽  
Inhibitory Concentration ◽  
Therapeutic Potential ◽  
E Coli ◽  
Checkerboard Assay ◽  
H Pylori

The antibacterial activity of geraniol and its effect in combination with ampicillin, amoxicillin and clarithromycin against Staphylococcus aureus, Escherichia coli and Helicobacter pylori was tested. The minimum inhibitory concentrations (MICs) and combinatory effects of geraniol against the bacteria were assessed by using the modified broth microdilution and checkerboard assay, respectively. The combinatory effect is expressed as fractional inhibitory concentration index (FICI). The MIC of geraniol against S. aureus, E. coli and H. pylori was found to be 11200, 5600, and 7325 μg/mL, respectively. A significant synergistic effect was observed with geraniol and ampicillin against S. aureus with FICI in the range 0.19 to 0.32. Geraniol and ampicillin exhibited a partial synergistic effect against E. coli. A similar effect was observed with geraniol and clarithromycin against S. aureus. A partial synergistic effect was observed with clarithromycin and geraniol against H. pylori with the FICI value in the range 0.86 to 0.89. An additive effect was observed with geraniol and amoxicillin combination against H. pylori. However, the amoxicillin and clarithromycin dose was reduced by thirty-two fold when combined with geraniol against H. pylori. The anti- H. pylori effect of geraniol with clarithromycin and amoxicillin could be of potential interest in the treatment of H. pylori infection and associated ulcers in humans. Further, geraniol, in combination with other antibiotics, has substantial therapeutic potential against S. aureus and E.coli infection.

scholarly journals Combinations of Lysostaphin with β-Lactams Are Synergistic against Oxacillin-Resistant Staphylococcus epidermidis

2002 ◽  
Vol 46 (6) ◽  
pp. 2017-2020 ◽  
Author(s):  
Nandini Kiri ◽  
Gordon Archer ◽  
Michael W. Climo
Keyword(s):  
Staphylococcus Aureus ◽  
Aortic Valve ◽  
Staphylococcus Epidermidis ◽  
Concentration Index ◽  
Inhibitory Concentration ◽  
Rabbit Model ◽  
Fractional Inhibitory Concentration ◽  
Fractional Inhibitory Concentration Index ◽  
Synergy Testing ◽  
Better Than

ABSTRACT Oxacillin-resistant Staphylococcus aureus is rapidly killed by the endopeptidase lysostaphin, and the addition of β-lactam antibiotics provides synergistic killing. We investigated the possibility that β-lactams given in combination with lysostaphin would improve the activity of lysostaphin against oxacillin-resistant Staphylococcus epidermidis (ORSE), which is normally less susceptible to lysostaphin. Checkerboard synergy testing was performed for lysostaphin given in combination with oxacillin against 10 ORSE isolates for which the lysostaphin MICs were ≥ 8 μg/ml. The fractional inhibitory concentration index ranged from 0.0234 to 0.2656, indicating synergy, which was confirmed in growth curve experiments. In the rabbit model of experimental aortic valve endocarditis using an ORSE strain, the combination of lysostaphin and nafcillin was as effective as vancomycin alone and significantly better than lysostaphin or nafcillin alone. We conclude that β-lactam antibiotics given in combination with lysostaphin are synergistic against many strains of ORSE.

scholarly journals ANTIMICROBIAL AND SYNERGISTIC ACTIVITY OF ESSENTIAL OILS FACING ISOLATED BACTERIA FROM SURGICAL STAFF’S

2019 ◽  
Vol 5 ◽  
Author(s):  
Tatiana Areas Cruz ◽  
Fernanda Rodrigues Torres ◽  
Monise Fazolin Petrucelli ◽  
Mariana Heinzen De Abreu ◽  
Silvia Sidneia Silva ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Essential Oils ◽  
Staphylococcus Epidermidis ◽  
Citrus Sinensis ◽  
Concentration Index ◽  
Inhibitory Concentration ◽  
Thymus Vulgaris ◽  
Synergistic Activity ◽  
Bacterial Strains ◽  
Microdilution Method

Objective:to evaluate antimicrobial and synergistic activity of essential oils (Citrus aurantifolia, Citrus sinensis, Mentha viridisand Thymus vulgaris) against isolated bacteria from surgical staff’s hands and bacterial strains. Method:the antimicrobial activity of oils was analyzed by microdilution method to determine the Minimum Inhibitory Concentration. Moreover, the combinatory effect of the oil that presented greater effectiveness using gentamycin sulphate through the Fractional Inhibitory Concentration index was tested. The study was performed over the period 2016-2018. Results:T. vulgaris was effective against Staphylococcus saprophyticus with a concentration of 0.0008 µL.mL-1and against the ATCC standard strains of Staphylococcus aureus, Salmonella choleraesuis,Staphylococcus epidermidis and Proteus vulgarisand the bacteria S. aureus, S. epidermidisand Bacillus sp. with MIC ≥ 0.10 µL.mL-1. This oil association with gentamycin sulphate showed synergistic activity againstS. epidermidis. Conclusion:T. vulgarisessential oil showed expressive antimicrobial activity against ATCC and isolated clinic microorganisms, suggesting broad spectrum of activity.

scholarly journals Antibiotics Susceptibility Profile and Synergistic Effects of Flavonoids with Antibiotics against Resistant Staphylococcus aureus from Asymptomatic Individuals

2020 ◽  
Vol 14 (4) ◽  
pp. 2669-2676
Author(s):  
Rudra Mishra ◽  
Pasupathi Rathinasabapathi
Keyword(s):  
Staphylococcus Aureus ◽  
Concentration Index ◽  
Inhibitory Concentration ◽  
Synergistic Effects ◽  
Sensitive Strain ◽  
Limited Information ◽  
Skin Microbiota ◽  
Antibiotics Susceptibility ◽  
Asymptomatic Individuals ◽  
Mic Value

Staphylococcus aureus exhibits resistance to most of the commonly used antibiotics. Although antibiotics suceptibility studies have been performed on the pathogen isolated from the patient samples, only limited information is available about that of S. aureus isolated from asymptomatic individuals. In this study, S. aureus was isolated from the skin microbiota of the asymptomatic individuals, and susceptibility of the pathogen against different antibiotics and plant flavonoids was compared to drug-sensitive strain. The minimum inhibitory concentration (MIC) value and IC50 of the pathogen were calculated against the antibiotics and flavonoids. The susceptibility pattern of the isolated strain showed higher resistance against erythromycin (100 μg mL-1) and vancomycin (25 μg mL-1). Based on the fractional inhibitory concentration index (FICI) values, the combinatory effects of antibiotics and flavonoids were categorized into synergistic, additive, and indifferent. The combination of rutin and erythromycin showed a synergistic effect with the concentrations of 31.25 μg mL-1 and 1.562 μg mL-1 against drug-sensitive strains of S. aureus. Similarly, the same combination showed synergistic effects against isolated strains at the concentration of 625 μg mL-1 and 12.5 μg mL-1.We observed an increase in drug resistance in the isolated strain of S. aureus in comparison to the drug-sensitive strain. To the best of our knowledge, this was the first study reporting increase in antimicrobial resistance of S. aureus present on asymptomatic individuals than the sensitive strain.

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