scholarly journals Quinoline Antimalarials Increase the Antibacterial Activity of Ampicillin

2021 ◽  
Vol 12 ◽  
Author(s):  
Olajumoke A. Olateju ◽  
Chinedum P. Babalola ◽  
Olujide O. Olubiyi ◽  
Olayinka A. Kotila ◽  
David A. Kwasi ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Paper Strip ◽  
Cell Integrity ◽  
Antimalarial Agents ◽  
Interaction Testing ◽  
Inhibition Zones ◽  
High Concentrations ◽  
The Impact ◽  
Concentration Indices

Bacterial and malaria co-infections are common in malaria endemic countries and thus necessitate co-administration of antibiotics and antimalarials. There have long been anecdotal clinical reports of interactions between penicillins and antimalarial agents, but the nature and mechanisms of these interactions remain to be investigated. In this study, we employed antimicrobial interaction testing methods to study the effect of two antimalarials on the antibacterial activity of ampicillin in vitro. Paper strip diffusion, a modified disc diffusion and checkerboard methods were used to determine the nature of interactions between ampicillin and quinoline antimalarials, chloroquine and quinine, against Gram-positive and Gram-negative bacteria. The impact of antimalarials and ampicillin-antimalarial drug combinations on cell integrity of test bacteria were determined by measuring potassium release. The tested antimalarials did not show substantial antibacterial activity but quinine was bactericidal at high concentrations. Chloroquine and quinine increased ampicillin activity, with increasing concentrations extending the antibacterial’s inhibition zones by 2.7-4.4 mm and from 1.1 to over 60 mm, respectively. Observed interactions were largely additive with Fractional Inhibitory Concentration Indices of >0.5-1 for all ampicillin-antimalarial combinations. Quinine and, to a lesser extent, chloroquine increase the activity of ampicillin and potentially other β-lactams, which has implications for combined clinical use.

A comparative study of the antibacterial activity of Quercus robur (Ethanolic extract) and Zinc oxide nanoparticles on Salmonella (In vitro)

2018 ◽  
Vol 9 (SPL1) ◽  
Author(s):  
Hams H. H. Alfattli ◽  
Ghufran Zuhair Jiber ◽  
Ghaidaa Gatea Abbass
Keyword(s):  
Zinc Oxide ◽  
Antibacterial Activity ◽  
Zinc Oxide Nanoparticles ◽  
Quercus Robur ◽  
Ethanolic Extract ◽  
Inhibitory Effect ◽  
Significant Inhibition ◽  
Oxide Nanoparticles ◽  
Inhibition Zones

This study which designed to evaluate the inhibitory effect of Ethanolic extract of (Quercusrobur) and Zinc oxide nanoparticles on the growth of one genus of enterobacteriacae (Salmonella). In vitro. For this purpose graduate concentrates for plant extract (50, 100, 200, 400 )mg/ml which prepared and compared with Zinc oxide nanoparticles of different concentration (2, 1, 0.5, 0.25) μg/ml,and examined. The result showed that the studied medicinal plant has antibacterial activity against this bacteria which used. The result showed that the plant has good activity in decrease the growth of this bacteria. The results of the study also showed that the nano-ZnO has very effective antibacterial action against the studied bacteria which was Salmonella,nanoparticles concentrations lead to increasing in the inhibition zones of tested bacterial growth. We also study the effect of three antibiotics Lomefloxacin (LOM), Ciprofloxacin (SIP) and Rifampin (RA) and the result showed,in a comparison within the tested bacteria,Salmonella had a significant inhibition increase in Lomefloxacin ; the ciprofloxacin showed effect on tested bacteria. However,Rifampin does not show any effect on tested bacteria.

scholarly journals Evaluation of the in vitro antibacterial activity of some essential oils and their blends against Staphylococcus spp. isolated from episodes of sheep mastitis

2021 ◽  
Author(s):  
Filippo Fratini ◽  
Margherita Giusti ◽  
Simone Mancini ◽  
Francesca Pisseri ◽  
Basma Najar ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Essential Oils ◽  
Diffusion Method ◽  
Minimal Bactericidal Concentration ◽  
Coagulase Negative Staphylococci ◽  
Disk Diffusion Method ◽  
In Vitro Antibacterial Activity ◽  
High Concentrations ◽  
Thymus Serpyllum

AbstractStaphylococcus aureus and coagulase-negative staphylococci are among the major causes of mastitis in sheep. The main goal of this research was to determine the in vitro antibacterial activity of several essential oils (EOs, n 30), then five of them were chosen and tested alone and in blends against staphylococci isolates. Five bacteria were isolated from episodes of ovine mastitis (two S. aureus and three S. xylosus). Biochemical and molecular methods were employed to identify the isolates and disk diffusion method was performed to determine their antimicrobial-resistance profile. The relative percentage of the main constituents in the tested essential oils and their blends was detected by GC-EIMS analysis. Antibacterial and bactericidal effectiveness of essential oils and blends were evaluated through minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). All of them showed sensitivity to the used antimicrobials. The EOs with the highest antibacterial activity were those belonging to the Lamiaceae family characterized by high concentrations of thymol, carvacrol and its precursor p-cymene, together with cinnamon EO, rich in cinnamaldehyde. In terms of both MIC and MBC values, the blend composed by Thymus capitatus EO 40%, Cinnamomum zeylanicum EO 20%, Thymus serpyllum EO 20% and Satureja montana EO 20% was found to be the most effective against all the isolates. Some essential oils appear to represent, at least in vitro, a valid tool against ovine mastitis pathogens. Some blends showed a remarkable effectiveness than the single oils, highlighting a synergistic effect in relation to the phytocomplex.

scholarly journals Antibiofilm and antivirulence potential of silver nanoparticles against multidrug-resistant Acinetobacter baumannii

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Helal F. Hetta ◽  
Israa M. S. Al-Kadmy ◽  
Saba Saadoon Khazaal ◽  
Suhad Abbas ◽  
Ahmed Suhail ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Antibacterial Activity ◽  
Acinetobacter Baumannii ◽  
Biofilm Formation ◽  
Microtiter Plate ◽  
Diffusion Method ◽  
Resistance Pattern ◽  
Infection Model ◽  
The Impact

AbstractWe aimed to isolate Acinetobacter baumannii (A. baumannii) from wound infections, determine their resistance and virulence profile, and assess the impact of Silver nanoparticles (AgNPs) on the bacterial growth, virulence and biofilm-related gene expression. AgNPs were synthesized and characterized using TEM, XRD and FTIR spectroscopy. A. baumannii (n = 200) were isolated and identified. Resistance pattern was determined and virulence genes (afa/draBC, cnf1, cnf2, csgA, cvaC, fimH, fyuA, ibeA, iutA, kpsMT II, PAI, papC, PapG II, III, sfa/focDE and traT) were screened using PCR. Biofilm formation was evaluated using Microtiter plate method. Then, the antimicrobial activity of AgNPs was evaluated by the well-diffusion method, growth kinetics and MIC determination. Inhibition of biofilm formation and the ability to disperse biofilms in exposure to AgNPs were evaluated. The effect of AgNPs on the expression of virulence and biofilm-related genes (bap, OmpA, abaI, csuA/B, A1S_2091, A1S_1510, A1S_0690, A1S_0114) were estimated using QRT-PCR. In vitro infection model for analyzing the antibacterial activity of AgNPs was done using a co-culture infection model of A. baumannii with human fibroblast skin cell line HFF-1 or Vero cell lines. A. baumannii had high level of resistance to antibiotics. Most of the isolates harbored the fimH, afa/draBC, cnf1, csgA and cnf2, and the majority of A. baumannii produced strong biofilms. AgNPs inhibited the growth of A. baumannii efficiently with MIC ranging from 4 to 25 µg/ml. A. baumannii showed a reduced growth rate in the presence of AgNPs. The inhibitory activity and the anti-biofilm activity of AgNPs were more pronounced against the weak biofilm producers. Moreover, AgNPs decreased the expression of kpsMII , afa/draBC,bap, OmpA, and csuA/B genes. The in vitro infection model revealed a significant antibacterial activity of AgNPs against extracellular and intracellular A. baumannii. AgNPs highly interrupted bacterial multiplication and biofilm formation. AgNPs downregulated the transcription level of important virulence and biofilm-related genes. Our findings provide an additional step towards understanding the mechanisms by which sliver nanoparticles interfere with the microbial spread and persistence.

scholarly journals Evaluating the Antibacterial Activity and Mode of Action of Thymol-Loaded Chitosan Nanoparticles Against Plant Bacterial Pathogen Xanthomonas campestris pv. campestris

2022 ◽  
Vol 12 ◽  
Author(s):  
Sarangapani Sreelatha ◽  
Nadimuthu Kumar ◽  
Tan Si Yin ◽  
Sarojam Rajani
Keyword(s):  
Electron Microscopy ◽  
Antibacterial Activity ◽  
Xanthomonas Campestris ◽  
Membrane Damage ◽  
Chitosan Nanoparticles ◽  
Bacterial Pathogen ◽  
Electron Microscopy Analysis ◽  
Rot Disease ◽  
The Impact

The bacterium Xanthomonas campestris pv. campestris (Xcc) causes black rot disease in cruciferous crops, resulting in severe yield loss worldwide. The excessive use of chemical pesticides in agriculture to control diseases has raised significant concern about the impact on the environment and human health. Nanoparticles have recently gained significant attention in agriculture owing to their promising application in plant disease control, increasing soil fertility and nutrient availability. In the current study, we synthesized thymol-loaded chitosan nanoparticles (TCNPs) and assessed their antibacterial activity against Xcc. The synthesis of TCNPs was confirmed by using ultraviolet–visible spectroscopy. Fourier-transform infrared spectroscopy, transmission electron microscopy, and scanning electron microscopy analysis revealed the functional groups, size, and shape of TCNPs, with sizes ranging from 54 to 250 nm, respectively. The antibacterial activity of TCNPs against Xcc was investigated in vitro by liquid broth, cell viability, and live dead staining assay, and all of them demonstrated the antibacterial activity of TCNPs. Furthermore, TCNPs were found to directly inhibit the growth of Xcc by suppressing the growth of biofilm formation and the production of exopolysaccharides and xanthomonadin. The ultrastructure studies revealed membrane damage in TCNP-treated Xcc cells, causing a release of intracellular contents. Headspace/gas chromatography (GC)–mass spectrometry (MS) analysis showed changes in the volatile profile of Xcc cells treated with TCNPs. Increased amounts of carbonyl components (mainly ketones) and production of new volatile metabolites were observed in Xcc cells incubated with TCNPs. Overall, this study reveals TCNPs as a promising antibacterial candidate against Xcc.

scholarly journals Hydroxyapatite-ciprofloxacin delivery system: Synthesis, characterisation and antibacterial activity

2018 ◽  
Vol 68 (2) ◽  
pp. 129-144 ◽  
Author(s):  
Maria-Viorica Ciocilteu ◽  
Andreea Gabriela Mocanu ◽  
Adriana Mocanu ◽  
Catalin Ducu ◽  
Oana Elena Nicolaescu ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Synthesis Process ◽  
Diffusion Controlled ◽  
Ft Ir ◽  
Inhibition Zones ◽  
Bacterial Growth Inhibition ◽  
Local Release

Abstract The main objective of this study was to synthesize hydroxyapatite-ciprofloxacin composites using a chemical precipitation method and to evaluate the properties and in vitro release profile of the drug from the hydroxyapatite-ciprofloxacin composites. Composite characterization was achieved by FT-IR, XRD and DLS. Ciprofloxacin determination was accomplished by HPLC, resulting in good incorporation efficiency of the drug (18.13 %). The in vitro release study (Higuchi model C = K t1/2 and Ritger-Peppas model, C = K t0.6) showed a diffusion-controlled mechanism. The antibacterial activity showed that the bacterial growth inhibition zones were approximately equal for the synthesis composites and for the mechanical mixture on the Staphylococcus aureus germ. The use of hydroxyapatite, which is a biocompatible, bioactive and osteoconductive material, with ciprofloxacin, which has good antibacterial activity in this composite, makes it suitable for the development of bone grafts. Furthermore, the synthesis process allows a slow local release of the drug.

scholarly journals Clavulanate Induces Expression of the Pseudomonas aeruginosa AmpC Cephalosporinase at Physiologically Relevant Concentrations and Antagonizes the Antibacterial Activity of Ticarcillin

1999 ◽  
Vol 43 (4) ◽  
pp. 882-889 ◽  
Author(s):  
Philip D. Lister ◽  
Victoria M. Gardner ◽  
Christine C. Sanders
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Bactericidal Effect ◽  
Pharmacodynamic Model ◽  
Immunocompromised Patients ◽  
Minimal Level ◽  
Quantitative Studies ◽  
Per Se ◽  
The Impact

ABSTRACT Although previous studies have indicated that clavulanate may induce AmpC expression in isolates of Pseudomonas aeruginosa, the impact of this inducer activity on the antibacterial activity of ticarcillin at clinically relevant concentrations has not been investigated. Therefore, a study was designed to determine if the inducer activity of clavulanate was associated with in vitro antagonism of ticarcillin at pharmacokinetically relevant concentrations. By the disk approximation methodology, clavulanate induction of AmpC expression was observed with 8 of 10 clinical isolates of P. aeruginosa. Quantitative studies demonstrated a significant induction of AmpC when clavulanate-inducible strains were exposed to the peak concentrations of clavulanate achieved in human serum with the 3.2- and 3.1-g doses of ticarcillin-clavulanate. In studies with three clavulanate-inducible strains in an in vitro pharmacodynamic model, antagonism of the bactericidal effect of ticarcillin was observed in some tests with regimens simulating a 3.1-g dose of ticarcillin-clavulanate and in all tests with regimens simulating a 3.2-g dose of ticarcillin-clavulanate. No antagonism was observed in studies with two clavulanate-noninducible strains. In contrast to clavulanate, tazobactam failed to induce AmpC expression in any strains, and the pharmacodynamics of piperacillin-tazobactam were somewhat enhanced over those of piperacillin alone against all strains studied. Overall, the data collected from the pharmacodynamic model suggested that induction per se was not always associated with reduced killing but that a certain minimal level of induction by clavulanate was required before antagonism of the antibacterial activity of its companion drug occurred. Nevertheless, since clinically relevant concentrations of clavulanate can antagonize the bactericidal activity of ticarcillin, the combination of ticarcillin-clavulanate should be avoided when selecting an antipseudomonal β-lactam for the treatment of P. aeruginosa infections, particularly in immunocompromised patients. For piperacillin-tazobactam, induction is not an issue in the context of treating this pathogen.

scholarly journals Evaluation and Comparison of Antibacterial Efficacy of Herbal Extracts in Combination with Antibiotics on Periodontal pathobionts: An in vitro Microbiological Study

Antibiotics ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 89 ◽  
Author(s):  
Shahabe Abullais Saquib ◽  
Nabeeh Abdullah AlQahtani ◽  
Irfan Ahmad ◽  
Mohammed Abdul Kader ◽  
Sami Saeed Al Shahrani ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Plant Extracts ◽  
Pathogenic Bacteria ◽  
Bacterial Resistance ◽  
Antimicrobial Agents ◽  
Synergistic Activity ◽  
Antibacterial Efficacy ◽  
Herbal Extracts ◽  
Inhibition Zones

Background: In the past few decades focus of research has been toward herbal medicines because of growing bacterial resistance and side effects of antimicrobial agents. The extract derived from the plants may increase the efficacy of antibiotics when used in combination against pathogenic bacteria. In the current study, the synergistic antibacterial efficacy of plant extracts in combination with antibiotics has been assessed on selected periodontal pathogens. Methods: Ethanolic extracts were prepared from Salvadora persica (Miswak) and Cinnamomum zeylanicum (Ceylon cinnamon), by the soxhalate method. Plaque samples were collected from clinical periodontitis patients to isolate and grow the periodontal pathobionts under favorable conditions. Susceptibility of bacteria to the extracts was assessed by gauging the diameter of the inhibition zones. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of plant extracts were determined against each bacterium. Synergistic activity of plants extract in combination with antibiotics against the bacteria was also assessed by measuring the diameter of the inhibition zones. Results: Ethanolic extract of both the plants showed an inhibitory effect on the proliferation and growth of all four strains of periodontal pathobionts. Maximum antibacterial activity was exhibited by C. zeylanicum against Tannerella forsythia (MIC = 1.56 ± 0.24 mg/mL, MBC = 6.25 ± 0.68 mg/mL), whereas among all the studied groups the minimum activity was reported by C. zeylanicum against Aggregatibacter actinomycetemcomitans the (MIC = 12.5 ± 3.25 mg/mL, MBC = 75 ± 8.23 mg/mL). Combination of herbal extracts with different antibiotics revealed a synergistic antibacterial effect. The best synergism was exhibited by S. persica with metronidazole against A. actinomycetemcomitans (27 ± 1.78). Conclusions: Current in vitro study showed variable antibacterial activity by experimented herbal extracts against periodontal pathobionts. The synergistic test showed significant antibacterial activity when plant extracts were combined with antibiotics.

scholarly journals In vitro effects of quinine on the antibacterial activity of erythromycin against bacteria of clinical relevance

2021 ◽  
Vol 14 (2) ◽  
pp. 077-086
Author(s):  
Oluremi Adejoke Akinwale ◽  
Uyi Oluwatobi Emokpae ◽  
Opeyemi Mariam Adebogun ◽  
Morenike Olutumbi Adeoye-Isijola ◽  
Olufunmiso Olusola Olajuyigbe
Keyword(s):  
Antibacterial Activity ◽  
Synergistic Effect ◽  
Clinical Relevance ◽  
Bacterial Infections ◽  
Antibacterial Activities ◽  
Antibacterial Effects ◽  
Agar Dilution ◽  
Inhibition Zones ◽  
In Vitro Effects

The study investigated the in vitro effects of quinine on the antibacterial activity of erythromycin for possible interactions. The antibacterial activities of each drug and their combinations were investigated by agar diffusion, agar and macrobroth dilution methods. While 100 µl of 1000 µg/ml of erythromycin produced inhibition zones ranging between 13 and 31 ± 1.0 mm in all the isolates except K. pneumoniae and P. aeruginosa ATCC 19582, combining the highest concentration of erythromycin with 35 µg/ml of quinine produced inhibition zones ranging between 14 and 34 ± 1.0 mm with the exception of S. flexneri KZN. Though quinine had no antibacterial effects on the isolates, erythromycin was effective at minimum inhibitory concentrations (MICs) ranging between 25 and 100 µg/ml while their combinations resulted in reduction of MICs of most of the isolates to 12.5 µg/ml except those against A. calcaoceuticus anitratus CSIR, Ps. aeruginosa ATCC 15442, P. shigelloides ATCC 51903, A. hydrophila ATCC 35654, Ps. aeruginosa ATCC 19582 and E. faecalis KZN that remained unchanged in agar dilution. While the MICs of erythromycin ranged between 25 and 50 µg/ml, the MICs of this antibiotic was reduced to concentrations ranging between 12.5 and 50 µg/ml indicating 50% to 75% in the presence of quinine. The combination of erythromycin and quinine, in vitro, resulted in synergistic (50%), additive/indifference (44.44%) and antagonistic (11.11%) interactions while quinine at concentrations lower than plasma quinine concentrations was inhibitory to the antibacterial activity of erythromycin. The synergistic effect may serve as remedy for bacterial infections in which the test bacteria have been implicated.

scholarly journals Antibacterial Activity of Buah Merah (Pandanus conoideus Lam.) Against Bacterial Oral Pathogen of Streptococcus sanguinis ATCC10556, Streptococcus mutans ATCC 25175, and Enterococcus faecalis ATCC 29212: An in Vitro Study

2020 ◽  
Vol 14 (1) ◽  
pp. 113-119 ◽  
Author(s):  
Lisda Damayanti ◽  
Ida Ayu Evaangelina ◽  
Avi Laviana ◽  
Yetty Herdiyati ◽  
Dikdik Kurnia
Keyword(s):  
Antibacterial Activity ◽  
Ethyl Acetate ◽  
Methanol Extract ◽  
Synergistic Effects ◽  
In Vitro Study ◽  
Inhibition Zone ◽  
Oral Bacteria ◽  
Inhibition Zones

Background: Caries and periodontitis are dental diseases caused by bacteria of S. sanguinis, S. mutans, and E. faecalis with three main etiological factors of the host, substrate, and time. Objective: This study proposed to investigate the antibacterial effects of Buah Merah (Pandanus conoideus Lam.) against oral bacteria of E.faecalis, S. mutans, and S. sanguinis. Materials and Methods: The Buah Merah was extracted with different solvents to yield n-hexane, ethyl acetate, methanol, and H2O extracts. The concentrations of single and mixture extracts were adjusted for antibacterial assay against bacteria of E. faecalis, S. mutans, and S. sanguinis strains through agar well diffusion assay with chlorhexidine, fosfomycin, and quercetin used as positive controls. Results: The ethyl acetate extract showed highest antibacterial activity against three oral bacterial of E. faecalis, S. mutans, and S. sanguinis with inhibition zones values of 9.3, 12.3, and 17.9 mm at 40%, respectively, together with their MIC and MBC values of 1250 & 2500, 0.312 & 0.625, and 0.312 & 0.625 ppm, respectively. For the formulation of extracts, combinations samples test gave various effects to different bacteria, with the best activity showed by methanol-ethyl acetate (M-Ea) extracts against S. mutans with an inhibition zone of 16.25 mm at 40 ppm. The strong and synergistic effect of methanol extract against S. mutans was supported by inhibition zones of the formulation of methanol extract-fosfomycin which showed an inhibition zone of 25.9 mm at 10 ppm. Conclusion: The extracts of Buah Merah demonstrated antibacterial activity against oral bacteria of E. faecalis, S. mutans, and S. sanguinis and gave important information for further in vivo clinical studies to determine the exact dosages and its effectiveness in practical application. These results prove the antimicrobial effects of Buah Merah extracts as alternative natural drugs with synergistic effects of active constituents.

scholarly journals Biphasic Effect of Pirfenidone on Angiogenesis

2022 ◽  
Vol 12 ◽  
Author(s):  
Donghao Gan ◽  
Wenxiang Cheng ◽  
Liqing Ke ◽  
Antonia RuJia Sun ◽  
Qingyun Jia ◽  
...  
Keyword(s):  
Vascular Endothelial Cells ◽  
Tube Formation ◽  
Endothelial Cell Migration ◽  
High Concentration ◽  
Low Concentrations ◽  
Biphasic Effect ◽  
High Concentrations ◽  
And Migration ◽  
The Impact

Pirfenidone (PFD), a synthetic arsenic compound, has been found to inhibit angiogenesis at high concentrations. However, the biphasic effects of different PFD concentrations on angiogenesis have not yet been elucidated, and the present study used an in vitro model to explore the mechanisms underlying this biphasic response. The effect of PFD on the initial angiogenesis of vascular endothelial cells was investigated through a Matrigel tube formation assay, and the impact of PFD on endothelial cell migration was evaluated through scratch and transwell migration experiments. Moreover, the expression of key migration cytokines, matrix metalloproteinase (MMP)-2 and MMP-9, was examined. Finally, the biphasic mechanism of PFD on angiogenesis was explored through cell signaling and apoptosis analyses. The results showed that 10–100 μM PFD has a significant and dose-dependent inhibitory effect on tube formation and migration, while 10 nM–1 μM PFD significantly promoted tube formation and migration, with 100 nM PFD having the strongest effect. Additionally, we found that a high concentration of PFD could significantly inhibit MMP-2 and MMP-9 expression, while low concentrations of PFD significantly promoted their expression. Finally, we found that high concentrations of PFD inhibited EA.hy926 cell tube formation by promoting apoptosis, while low concentrations of PFD promoted tube formation by increasing MMP-2 and MMP-9 protein expression predominantly via the EGFR/p-p38 pathway. Overall, PFD elicits a biphasic effect on angiogenesis through different mechanisms, could be used as a new potential drug for the treatment of vascular diseases.

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