Bacterial infections have become more challenging to treat due to the emergence of multidrug-resistant pathogenic bacteria. Combined antibiotics prove to be a relatively effective method to control such resistant strains. This study aim to investigate synergistic activity of eugenol combined with colistin against a collection of clinical isolated Escherichia coli (E.coli) strains, and to evaluate potential interaction.
Antimicrobial susceptibility, minimum inhibitory concentration (MIC) and fractional inhibitory concentration index (FICI) of the bacteria were determined by disk diffusion assay, broth microdilution method and checkerboard assay, respectively. The mcr-1 mRNA expression was measured by Real-time PCR. To predict possible interactions between eugenol and MCR-1, molecular docking assay was taken.
For total fourteen strains including eight colistin-resistant strains, eugenol was determined with MIC values of 4 to 8 μg/mL. Checkerboard dilution test suggested that eugenol exhibited synergistic activity when combined with colistin (FICI ranging from 0.375 to 0.625). Comparison analysis of Real-time PCR showed that synergy could significantly down-regulate expression of mcr-1 gene. A metal ion coordination bond with catalytic zinc atom and a hydrogen bond with crucial amino acid residue Ser284 of MCR-1 were observed after molecular docking, indicating antibacterial activity and direct molecular interactions of eugenol with MCR-1 protein.
Our results demonstrated that eugenol exhibited synergistic effect with colistin and enhanced its antimicrobial activity. This might further contribute to the antibacterial actions against colistin-resistant E.coli strains.
Synergistic effect of eugenol with colistin against colistin-resistant Escherichia coli isolates.
von Wintersdorff CJ, Wolffs PF, van Niekerk JM, Beuken E, van Alphen LB, Stobberingh EE, Oude Lashof AM, Hoebe CJ, Savelkoul PH, Penders J. Detection of the plasmid-mediated colistin-resistance gene mcr-1 in faecal metagenomes of dutch travellers. J Antimicrob Chemother. 2016;71:3416–9. CrossRefPubMed
Fisher K, Phillips C. Potential antimicrobial uses of essential oils in food: is citrus the answer? Trends Food Sci Technol. 2008;19:156–64. CrossRef
Bajpai VK, Baek KH, Kang SC. Control of salmonella in foods by using essential oils: a review. Food Res Int. 2012;45:722–34. CrossRef
Rs P, Zhou F, Ji B, Xu J. Evaluation of combined antibacterial effects of eugenol, cinnamaldehyde, thymol, and carvacrol against e. Coli with an improved method. J Food Sci. 2009;74:M379–83. CrossRef
Lv F, Liang H, Yuan Q, Li C. In vitro antimicrobial effects and mechanism of action of selected plant essential oil combinations against four food-related microorganisms. Food Res Int. 2011;44:3057–64. CrossRef
Fadli M, Bolla JM, Mezrioui NE, Pagès JM, Hassani L. First evidence of antibacterial and synergistic effects of thymus riatarum essential oil with conventional antibiotics. Ind Crop Prod. 2014;61:370–6. CrossRef
Calo JR, Crandall PG, O'Bryan CA, Ricke SC. Essential oils as antimicrobials in food systems – a review. Food Control. 2015;54:111–9. CrossRef
Rice LB. Challenges in identifying new antimicrobial agents effective for treating infections with acinetobacter baumannii and pseudomonas aeruginosa. Clin Infect Dis 2006; 43 \ 2: S100–S105.
Xavier BB, Lammens C, Ruhal R, Kumar-Singh S, Butaye P, Goossens H, Malhotra-Kumar S. Identification of a novel plasmid-mediated colistin-resistance gene, mcr-2, in escherichia coli, belgium, june 2016. Euro Surveill. 2016;21
Ma G, Zhu Y, Yu Z, Ahmad A, Zhang H. High resolution crystal structure of the catalytic domain of mcr-1. Sci Rep. 2016;6(39540)
Hyldgaard M, Mygind T, Meyer RL. Essential oils in food preservation: mode of action, synergies, and interactions with food matrix components. Front Microbiol. 2012;3(12)
Dhara L, Tripathi A. Antimicrobial activity of eugenol and cinnamaldehyde against extended spectrum beta lactamase producing enterobacteriaceae by in vitro and molecular docking analysis. European Journal of Integrative Medicine. 2013;5:527–36. CrossRef
Bajpai VK, Sharma A, Baek KH. Antibacterial mode of action of cudrania tricuspidata fruit essential oil, affecting membrane permeability and surface characteristics of food-borne pathogens. Food Control. 2013;32:582–90. CrossRef
Cui H, Zhang X, Zhou H, Zhao C, Lin L. Antimicrobial activity and mechanisms of salvia sclarea essential oil. Bot Stud. 2015;56
Huang DF, Xu JG, Liu JX, Zhang H, Hu QP. Chemical constituents, antibacterial activity and mechanism of action of the essential oil from cinnamomum cassia bark against four food-related bacteria. Microbiology. 2014;83:357–65. CrossRef
Li CM, Yu JP. Chemical composition, antimicrobial activity and mechanism of action of essential oil from the leaves ofmacleaya cordata(willd.) r. Br. J Food Saf. 2015;35:227–36. CrossRef
Skočibušić M, Bezić N, Dunkić V. Phytochemical composition and antimicrobial activities of the essential oils from satureja subspicata vis. Growing in croatia. Food Chem. 2006;96:20–8. CrossRef
- Synergistic effect of eugenol with Colistin against clinical isolated Colistin-resistant Escherichia coli strains
- BioMed Central
Neu im Fachgebiet Innere Medizin
Meistgelesene Bücher aus der Inneren Medizin
Mail Icon II