Antibacterial effects of two Iranian plant extracts and their synergistic effects on Staphylococcus aureus in laboratory medium

AbstractCombination of various compounds and essential oils for pharmaceutical formulations withdraw attention. In this present study, it was aimed to evaluate the in vitro potential synergistic antibacterial effect of Lavandula latifolia (spike lavender) essential oil with camphor by using the checkerboard method against the human pathogens; Staphylococcus aureus and Listeria monocytogenes. Pharmacopoeia quality L. latifolia essential oil and racemic camphor were analyzed and verified by GC-FID and GC/MS, simultaneously. In vitro antibacterial activity of essential oil and camphor (MIC range: 0.16–20 mg/mL) and standard antimicrobial clarithromycin (MIC range: 0.125–16 μg/mL) were carried out by broth microdilution against S. aureus and L. monocytogenes standard strains, respectively. Resulting antibacterial effects were evaluated for their fractional inhibitory concentrations (FICs) as antagonistic, additive and synergistic effects. The analytical results showed that the major component of essential oil was linalool (45.2%) and 1,8-cineole (25.6%). Antibacterial effects of essential oil were determined as MIC 1.25–5 mg/mL. As a result of the experiments, L. latifolia essential oil–camphor combinations were identified as “synergistic (FIC ≤ 0.5), and additive (0.5 < FIC ≤ 1)” in the respective combinations, suggesting further evaluation for formulations for potential antimicrobial applications in food and pharmaceuticals.

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Tellimagrandin II, A Type of Plant Polyphenol Extracted from Trapa bispinosa Inhibits Antibiotic Resistance of Drug-Resistant Staphylococcus aureus

International Journal of Molecular Sciences ◽

10.3390/ijms20225790 ◽

2019 ◽

Vol 20 (22) ◽

pp. 5790 ◽

Cited By ~ 2

Author(s):

Yu-Wei Chang ◽

Wan-Chun Huang ◽

Chun-Yu Lin ◽

Wen-Hung Wang ◽

Ling-Chien Hung ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Inhibitory Concentration ◽

Synergistic Effects ◽

Drug Resistant ◽

Penicillin Binding Protein ◽

Antibacterial Effects ◽

Transmission Electron ◽

Antistaphylococcal Activity ◽

Global Concern ◽

Tellimagrandin Ii

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) has become a critical global concern. Identifying new candidates of anti-S. aureus agents is urgently required because the therapeutic strategies for infected patients are limited currently. Therefore, the present study investigated whether Tellimagrandin II (TGII), a pure compound extracted from the shells of Trapa bispinosa, exhibits antibacterial effects against MRSA. We first showed that TGII exerted potent inhibitory activity against MRSA with a minimum inhibitory concentration of 128 μg/mL. The obtained fractional inhibitory concentration suggested that TGII could alone exert antistaphylococcal activity, and TGII combined with low doses of antibiotics displayed synergistic effects against MRSA. Moreover, we found that TGII exerted bactericidal activity by reducing the expression of mecA followed by the negative regulation of the penicillin-binding protein 2a (PBP2a) of MRSA. Transmission electron microscopy (TEM) images further confirmed that TGII destroyed the integrity of the cell wall of MRSA and caused the loss of cytoplasm content. In conclusion, we evidenced the antibacterial effects of TGII against MRSA, which enables the effective dose of current antibiotics to be reduced and the predicament of drug-resistant S. aureus isolates to be overcome.

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Synergistic antibacterial effects of herbal extracts and antibiotics on methicillin-resistant Staphylococcus aureus: A computational and experimental study

Experimental Biology and Medicine ◽

10.1177/1535370216689828 ◽

2017 ◽

Vol 242 (7) ◽

pp. 731-743 ◽

Cited By ~ 22

Author(s):

Chiu-Fai Kuok ◽

Sai-On Hoi ◽

Chi-Fai Hoi ◽

Chi-Hong Chan ◽

Io-Hong Fong ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Inhibitory Concentration ◽

Synergistic Effects ◽

Medicinal Herbs ◽

Resistant Bacteria ◽

Antibacterial Effects ◽

In Vitro Susceptibility ◽

Methicillin Resistant

Antibiotic resistance has become a serious global concern, and the discovery of antimicrobial herbal constituents may provide valuable solutions to overcome the problem. In this study, the effects of therapies combining antibiotics and four medicinal herbs on methicillin-resistant Staphylococcus aureus (MRSA) were investigated. Specifically, the synergistic effects of Magnolia officinalis, Verbena officinalis, Momordica charantia, and Daphne genkwa in combination with oxacillin or gentamicin against methicillin-resistant (ATCC43300) and methicillin-susceptible (ATCC25923) S. aureus were examined. In vitro susceptibility and synergistic testing were performed to measure the minimum inhibitory concentration and fractional inhibitory concentration (FIC) index of the antibiotics and medicinal herbs against MRSA and methicillin-susceptible S. aureus. To identify the active constituents in producing these synergistic effects, in silico molecular docking was used to investigate the binding affinities of 139 constituents of the four herbs to the two common MRSA inhibitory targets, penicillin binding proteins 2a (PBP2a) and 4 (PBP4). The physicochemical and absorption, distribution, metabolism, and excretion properties and drug safety profiles of these compounds were also analyzed. D. genkwa extract potentiated the antibacterial effects of oxacillin against MRSA, as indicated by an FIC index value of 0.375. M. officinalis and V. officinalis produced partial synergistic effects when combined with oxacillin, whereas M. charantia was found to have no beneficial effects in inhibiting MRSA. Overall, tiliroside, pinoresinol, magnatriol B, and momorcharaside B were predicted to be PBP2a or PBP4 inhibitors with good drug-like properties. This study identifies compounds that deserve further investigation with the aim of developing therapeutic agents to modulate the effect of antibiotics on MRSA. Impact statement Antibiotic resistant is a well-known threat to global health and methicillin-resistant Staphylococcus aureus is one of the most significant ones. These resistant bacteria kill thousands of people every year and therefore a new effective antimicrobial treatment is necessary. This study identified the herbs and their associated bioactive ingredients that can potential the effects of current antibiotics. These herbs have long history of human usage in China and have well-defined monograph in the Chinese Pharmacopeia. These indicate their relatively high clinical safety and may have a quicker drug development process than that of a new novel antibiotic. Based on the results of this study, the authors will perform further in vitro and animal studies, aiming to accumulate significant data for the application of clinical trial.

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A Molecular Insight into the Synergistic Mechanism of Nigella sativa (Black Cumin) with β-Lactam Antibiotics against Clinical Isolates of Methicillin-Resistant Staphylococcus aureus

Applied Sciences ◽

10.3390/app11073206 ◽

2021 ◽

Vol 11 (7) ◽

pp. 3206

Author(s):

Lorina I. Badger-Emeka ◽

Promise Madu Emeka ◽

Hairul Islam M. Ibrahim

Keyword(s):

Staphylococcus Aureus ◽

Mechanism Of Action ◽

Methicillin Resistant Staphylococcus Aureus ◽

Nigella Sativa ◽

Synergistic Effects ◽

Diffusion Method ◽

Methicillin Resistant ◽

Cell Wall Disruption ◽

Time Kill ◽

Insight Into

Methicillin-resistant Staphylococcus aureus (MRSA) infection is detrimental to hospitalized patients. With diminishing choices of antibiotics and the worry about resistance to colistin in synergistic combined therapy, there are suggestions for the use of herbal derivatives. This investigation evaluated the synergistic effects of Nigella sativa (NS) in combination with beta-lactam (β-lactam) antibiotics on extreme drug-resistant (XDR) MRSA isolates. NS concentrations of 10, 7.5, 5.0, 2.5, 1.0, and 0.1 µg/mL, alone and in combination with β-lactam antibiotics, were used to determine the antimicrobial susceptibility of MRSA isolates by the well diffusion method. Time–kill assays were performed using a spectrophotometer, with time–kill curves plotted and synergism ascertained by the fractional inhibitory concentration (FIC). Scanning and transmission electron microscopy were used to gain insight into the mechanism of action of treated groups. Isolates were inhibited by the NS concentrations, with differences in the zones of inhibition being statistically insignificant at p < 0.05. There were statistically significant differences in the time–kill assay for the MRSA isolates. In addition, NS combined with augmentin showed better killing than oxacillin and cefuroxime. The mechanism of action shown by the SEM and TEM results revealed cell wall disruption, which probably created interference that led to bacterial lysis.

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Trans-Cinnamaldehyde Exhibits Synergy with Conventional Antibiotic against Methicillin-Resistant Staphylococcus aureus

International Journal of Molecular Sciences ◽

10.3390/ijms22052752 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2752

Author(s):

Shu Wang ◽

Ok-Hwa Kang ◽

Dong-Yeul Kwon

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Synergistic Effects ◽

Regulatory Gene ◽

Western Blot Assay ◽

Methicillin Resistant ◽

Wide Range ◽

Kill Curve ◽

Conventional Antibiotics ◽

Time Kill

Methicillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen worldwide and has acquired multiple resistance to a wide range of antibiotics. Hence, there is a pressing need to explore novel strategies to overcome the increase in antimicrobial resistance. The present study aims to investigate the efficacy and mechanism of plant-derived antimicrobials, trans-cinnamaldehyde (TCA) in decreasing MRSA’s resistance to eight conventional antibiotics. A checkerboard dilution test and time–kill curve assay are used to determine the synergistic effects of TCA combined with the antibiotics. The results indicated that TCA increased the antibacterial activity of the antibiotics by 2-16-fold. To study the mechanism of the synergism, we analyzed the mecA transcription gene and the penicillin-binding protein 2a level of MRSA treated with TCA by quantitative RT-PCR or Western blot assay. The gene transcription and the protein level were significantly inhibited. Additionally, it was verified that TCA can significantly inhibit the biofilm, which is highly resistant to antibiotics. The expression of the biofilm regulatory gene hld of MRSA after TCA treatment was also significantly downregulated. These findings suggest that TCA maybe is an exceptionally potent modulator of antibiotics.

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Strategically prolonged release of multiple antibacterial components from a thin film coating for synergistic effects against Staphylococcus aureus infections

RSC Advances ◽

10.1039/c9ra03365c ◽

2019 ◽

Vol 9 (56) ◽

pp. 32683-32690 ◽

Cited By ~ 1

Author(s):

Meijun Song ◽

Haidong Zhu ◽

Lin Ye ◽

Chengxiang Liu ◽

Zhaojun Xu

Keyword(s):

Thin Film ◽

Staphylococcus Aureus ◽

Synergistic Effects ◽

Film Coating ◽

Prolonged Release ◽

Thin Film Coating

Biomaterial-associated infections (BAIs) remain a major challenge in clinical surgery because they can potentially cause serious disabilities in patients.

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In VitroActivities of Daptomycin-, Vancomycin-, and Teicoplanin-Loaded Polymethylmethacrylate against Methicillin-Susceptible, Methicillin-Resistant, and Vancomycin-Intermediate Strains of Staphylococcus aureus

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05312-11 ◽

2011 ◽

Vol 55 (12) ◽

pp. 5480-5484 ◽

Cited By ~ 45

Author(s):

Yuhan Chang ◽

Wen-Chien Chen ◽

Pang-Hsin Hsieh ◽

Dave W. Chen ◽

Mel S. Lee ◽

...

Keyword(s):

Staphylococcus Aureus ◽

High Performance ◽

Low Dose ◽

Antibacterial Activities ◽

High Dose ◽

Bone Cements ◽

Antibacterial Effects ◽

Methicillin Resistant ◽

Content Type

ABSTRACTThe objective of this study was to evaluate the antibacterial effects of polymethylmethacrylate (PMMA) bone cements loaded with daptomycin, vancomycin, and teicoplanin against methicillin-susceptibleStaphylococcus aureus(MSSA), methicillin-resistantStaphylococcus aureus(MRSA), and vancomycin-intermediateStaphylococcus aureus(VISA) strains. Standardized cement specimens made from 40 g PMMA loaded with 1 g (low-dose), 4 g (middle-dose) or 8 g (high-dose) antibiotics were tested for elution characteristics and antibacterial activities. The patterns of release of antibiotics from the cement specimens were evaluated usingin vitrobroth elution assay with high-performance liquid chromatography. The activities of broth elution fluid against differentStaphylococcus aureusstrains (MSSA, MRSA, and VISA) were then determined. The antibacterial activities of all the tested antibiotics were maintained after being mixed with PMMA. The cements loaded with higher dosages of antibiotics showed longer elution periods. Regardless of the antibiotic loading dose, the teicoplanin-loaded cements showed better elution efficacy and provided longer inhibitory periods against MSSA, MRSA, and VISA than cements loaded with the same dose of vancomycin or daptomycin. Regarding the choice of antibiotics for cement loading in the treatment ofStaphylococcus aureusinfection, teicoplanin was superior in terms of antibacterial effects.

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In vitro activity of allicin combined with two antibiotics on intestinal Shigella

Infection International ◽

10.1515/ii-2017-0152 ◽

2017 ◽

Vol 6 (1) ◽

pp. 25-29 ◽

Cited By ~ 1

Author(s):

Yuchi Jia ◽

Xiaomei Wu

Keyword(s):

Intestinal Tract ◽

Inhibitory Concentration ◽

Synergistic Effects ◽

Antagonistic Effect ◽

Additive Effects ◽

In Vitro Activity ◽

Antibacterial Effects ◽

Combined Application ◽

Combined Use

Abstract Objective We aimed to evaluate the combined antibacterial effects of allicin in combination with levofloxacin and ceftriaxone on Shigella isolated from the intestinal tract in vitro. Materials and Methods Using a checkerboard design, broth microdilution assay was used to test the effects of the compounds on the organism. We also determined the MIC of the two groups of antibacterial drugs against 30 strains of Shigella and calculated the fractional inhibitory concentration (FIC) index, to judge the combination effect. Result After the combined application of allicin and ceftriaxone the MIC decreased significantly. Distribution of the FIC index was as follows: FIC ≤0.5, accounting for 10%; 0.5< FIC ≤1.0, accounting for 60%; 1 < FIC ≤2, accounting for 30%; FIC >2, percentage is zero. After combined application of allicin and levofloxacin, distribution of FIC index was as follows: FIC≤0.5, ratio is zero; 0.5< FIC ≤1, accounting for 56.7%; 1 < FIC ≤2, accounting for 43.3%; FIC >2, ratio is zero. Conclusion After the combined use of ceftriaxone, levofloxacin, and allicin, most of the tests showed synergistic effects and additive effects on Shigella, while some of them showed no correlation and no antagonistic effect.

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