Synergistic anti-bacterial and proteomic effects of epigallocatechin gallate on clinical isolates of imipenem-resistant Klebsiella pneumoniae

Cho, Yun-Seok; Oh, Jay Jooyoung; Oh, Keun-Yeob

doi:10.1016/j.phymed.2011.03.012

Cited by 36 publications

(24 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Though the tea tree oil has been approved for medicinal use in Australia since 1920s, clinical resistance to the essential oil has not yet been reported [73]. In an in vitro resistance induction study, resistant sub-population of MRSA was detected when the S. aureus was repeatedly exposed to tea tree oil for several generations [74]. Conversely, in two other studies using different parameters to study changes in susceptibility of the multiple antibiotic resistance phenotype bacteria, little evidence was provided to suggest the occurrence of resistance to tea tree oil [85, 86].…”

Section: Bacterial Resistance To Essential Oilsmentioning

confidence: 99%

Essential Oils, A New Horizon in Combating Bacterial Antibiotic Resistance

Yap¹,

Yiap²,

Hu³

et al. 2014

TOMICROJ

332

225

View full text Add to dashboard Cite

For many years, the battle between humans and the multitudes of infection and disease causing pathogens continues. Emerging at the battlefield as some of the most significant challenges to human health are bacterial resistance and its rapid rise. These have become a major concern in global public health invigorating the need for new antimicrobial compounds. A rational approach to deal with antibiotic resistance problems requires detailed knowledge of the different biological and non-biological factors that affect the rate and extent of resistance development. Combination therapy combining conventional antibiotics and essential oils is currently blooming and represents a potential area for future investigations. This new generation of phytopharmaceuticals may shed light on the development of new pharmacological regimes in combating antibiotic resistance. This review consolidated and described the observed synergistic outcome between essential oils and antibiotics, and highlighted the possibilities of essential oils as the potential resistance modifying agent.

show abstract

Section: Bacterial Resistance To Essential Oilsmentioning

confidence: 99%

Essential Oils, A New Horizon in Combating Bacterial Antibiotic Resistance

Yap¹,

Yiap²,

Hu³

et al. 2014

TOMICROJ

332

225

View full text Add to dashboard Cite

show abstract

“…EGCG exerts these anti-bacterial activities partly by damaging bacterial cytoplasmic lipids [22-25], membrane proteins [26], or cytoplasmic enzymes (e.g., gelatinase, protein tyrosine phosphatase, dihydrofolate reductase, or DNA gyrase) [27-29]. Indeed, scanning electron microscopic analysis revealed that EGCG treatment caused alterations in both bacterial cell morphology [30] and outer membrane (e.g., wrinkling with perforations) [31]. As a possible consequence, EGCG impaired the cytoplasmic membrane efflux pump activities, and consequently elevated intracellular antibiotics concentrations, supporting the possible use of EGCG as an adjuvant in antibacterial therapy [19].…”

Section: Introductionmentioning

confidence: 99%

Green Tea Catechins Quench the Fluorescence of Bacteria-Conjugated Alexa Fluor Dyes

Zhao¹,

Li²,

Zhu³

et al. 2013

IADT

View full text Add to dashboard Cite

Accumulating evidence suggests that Green tea polyphenolic catechins, especially the (-)-epigallocatechin gallate (EGCG), can be cross-linked to many proteins, and confer a wide range of anti-bacterial activities possibly by damaging microbial cytoplasmic lipids and proteins. At the doses that conferred protection against lethal polymicrobial infection (induced by cecal ligation and puncture), EGCG significantly reduced bacterial loads particularly in the liver and lung. To elucidate its bactericidal mechanisms, we determined whether EGCG affected the fluorescence intensities of bacteria-conjugated Alexa Fluor 488 or 594 dyes. When mixed with unconjugated Alexa Fluor 488 or 594 dyes, EGCG or analogs did not affect the fluorescence intensity of these dyes. In a sharp contrast, EGCG and some analogs (e.g., Catechin Gallate, CG), markedly reduced the fluorescence intensity of Gram-positive Staphylococcus aureus-conjugated Alexa 594 and Gram-negative Escherichia coli-conjugated Alexa 488. Interestingly, co-treatment with ethanol impaired the EGCG-mediated fluorescence quenching of the G+ S. aureus, but not of the G- E. coli-conjugated Alexa Flour dyes. In light of the notion that Alexa Fluor dyes can be quenched by aromatic amino acids, it is plausible that EGCG exerts anti-microbial activities possibly by altering microbial protein conformations and functions. This possibility can now be explored by screening other fluorescence-quenching agents for possible antimicrobial activities.

show abstract

“…Ugwu et al have also shown that the inhibitory concentrations of carboxamides against MT is in the range of 25-50 µg/ml [23] . Cho et al showed that the inhibitory concentrations of EGCG against the antibiotic resistant Imipenem Klebsiella pneumonia strains to be in the range of 300-650 µg/ml [12] .…”

Section: Resultsmentioning

confidence: 99%

“…Hu et al have observed a potent synergy between EGCG and Ampicillin/Sulbactam in the treatment of Methicillinresistant Staphylococcus aureus infection [11] . Cho et al have reported that EGCG exhibited synergistic activity with the antibiotic Imipenem in treatment of the pathogenic bacteria, Klebsiella pneumoniae implicated in pneumonia infections [12] . Novy et al have also reported the synergistic and additive effects of EGCG in combination with antibiotics such as oxytetracycline against S. aureus strains [13] .…”

Section: Research Papermentioning

confidence: 99%

Epigallocatechin Gallate, a Green Tea Polyphenol Inhibits Mycobacterium smegmatis: In silico and In vitro Studies

Narayanan¹,

Ramesh²

2017

pharmaceutical-sciences

View full text Add to dashboard Cite

Narayanan and Ramesh: Epigallocatechin Gallate Inhibits M. smegmatisPresence of multidrug resistant strains makes treatment of tuberculosis difficult. Conventional frontline antituberculosis therapy has high incidence of treatment failure due to non-adherence and severe side effects, and therefore warrants alternative approaches using safe, natural compounds. (-) Epigallocatechin gallate, a green tea catechin with significant antimicrobial properties, and its derivatives have been studied for their inhibitory effects on Mycobacterium smegmatis. Enoyl reductase (Inh A, PDB ID: 2NV6), an important drug target inhibited by the antituberculosis drug, isoniazid, was docked with geometrically optimized conformation of epigallocatechin gallate and two of its derivatives using AutoDock software. Perpropionate and permethyl derivatives of epigallocatechin gallate were synthesized and, along with epigallocatechin gallate, evaluated for their inhibitory and cytotoxic properties against M. smegmatis using microplate dilution method and alamarBlue® assay, respectively. Ames test was performed to assess the mutagenic potential of epigallocatechin gallate. It was docked successfully onto the InhA with docking energy of -9.38 kcal mol -1 . Analysis of neighbouring groups revealed 11 amino acid residues common to both isoniazid and epigallocatechin gallate. The minimum inhibitory concentrations for epigallocatechin gallate, perpropionate and permethyl were found to be 128 (58.2% inhibition), 8 (32.9%) and 4 (12.5%) µg/ml, respectively. Epigallocatechin gallate showed a cytotoxicity of 18.6% at a concentration of 8 µg/ml, while the two derivatives did not show any toxicity, even at 64 µg/ml. Ames test revealed the absence of mutagenicity for epigallocatechin gallate, in presence and absence of metabolic activation. Nonmutagenic epigallocatechin gallate inhibits the growth of M. smegmatis and warrants further investigation as an adjunct therapy for pathogenic mycobacteria.

show abstract

Synergistic anti-bacterial and proteomic effects of epigallocatechin gallate on clinical isolates of imipenem-resistant Klebsiella pneumoniae

Cited by 36 publications

References 25 publications

Essential Oils, A New Horizon in Combating Bacterial Antibiotic Resistance

Essential Oils, A New Horizon in Combating Bacterial Antibiotic Resistance

Green Tea Catechins Quench the Fluorescence of Bacteria-Conjugated Alexa Fluor Dyes

Epigallocatechin Gallate, a Green Tea Polyphenol Inhibits Mycobacterium smegmatis: In silico and In vitro Studies

Contact Info

Product

Resources

About