Zingerone silences quorum sensing and attenuates virulence of Pseudomonas aeruginosa

Gan

Comp Rev Food Sci Food Safe

et al. 2020

In recent decades, reduced antimicrobial effectiveness, increased bacterial infection, and newly emerged microbial resistance have become global public issues, leading to an urgent need to find effective strategies to counteract these problems. Strategies targeting bacterial virulence factors rather than bacterial survival have attracted increasing interest, since the modulation of virulence factors may prevent the development of drug resistance in bacteria. Spices are promising natural sources of antivirulence compounds owing to their wide availability, diverse antivirulence phytochemical constituents, and generally favorable safety profiles. Essential oils are the predominant and most important antivirulence components of spices. This review addresses the recent efforts of using spice essential oils to inhibit main bacterial virulence traits, including the quorum sensing system, biofilm formation, motility, and toxin production, with an intensive discussion of related mechanisms. We hope that this review can provide a better understanding of the antivirulence properties of spice essential oils, which have the potential to be used as antibiotic alternatives by targeting bacterial virulence. K E Y W O R D Sbiofilm, mechanisms, motility, quorum sensing, spice essential oils, toxin 1018

Section: Bacterial Toxinsmentioning

confidence: 99%

Antivirulence properties and related mechanisms of spice essential oils: A comprehensive review

Gan

Comp Rev Food Sci Food Safe

et al. 2020

“…Hence, the inhibition of this signaling system has emerged as a promising approach to target infections caused by P. aeruginosa (Bjarnsholt et al 2010;Rampioni et al 2014). To date, several natural and synthetic compounds have been documented as potential inhibitors of QS in P. aeruginosa, including 4-nitro-pyridine-N-oxide (NPO) , meta-bromo-thiolactone (mBTL) (O'Loughlin et al 2013), organosulfur (Cady et al 2012), cinnamon oil (Kalia et al 2015), zingerone (Kumar et al 2015) and others. These compounds do not kill the bacterial cell and are likely to develop less resistance towards conventional antibiotics (Bhardwaj et al 2013).…”

Section: Substantial Inhibition Of Qs-mediated Virulence Factors By Pmentioning

confidence: 99%

Biofilm inhibition and anti-quorum sensing activity of phytosynthesized silver nanoparticles against the nosocomial pathogen Pseudomonas aeruginosa

et al. 2019

Quorum sensing (QS), the communication signaling network, regulates biofilm formation and several virulence factors in Pseudomonas aeruginosa PAO1, a nosocomial opportunistic pathogen. QS is considered to be a challenging target for compounds antagonistic to virulent factors. Biologically synthesized silver nanoparticles (AgNPs) are reported as anti-QS and anti-biofilm drugs against bacterial infections. The present study reports on the synthesis and characterization of Piper betle (Pb) mediated AgNPs (Pb-AgNPs). The anti-QS activity of Pb-AgNPs against Chromobacterium violaceum and the potential effect of Pb-AgNPs on QS-regulated phenotypes in PAO1 were studied. FTIR analysis exhibited that Pb-AgNPs had been capped by phytochemical constituents of Pb. Eugenol is one of the active phenolic phytochemicals in Pb leaves, therefore molecular docking of eugenol-conjugated AgNPs on QS regulator proteins (LasR, LasI and MvfR) was performed. Eugenol-conjugated AgNPs showed considerable binding interactions with QS-associated proteins. These results provide novel insights into the development of phytochemically conjugated nanoparticles as promising anti-infective candidates.

Colloids and Surfaces B: Biointerfaces

“…Therefore, targeting and blocking QS circuits in bacteria may represent a strategy to disarm their virulence and hence, making them more susceptible to elimination by the host immune system or low doses of antibiotics [10]. Anti-virulent agents possessing QS inhibitory activity might not pose selective pressure on bacterial pathogens and hence, may contribute to reduce the rapid emergence of so-called "superbugs", bacteria resistant to several antibiotics [11,12]. Disruption of QS-regulated processes has been accepted to reduce accumulation of virulence factors at the infection site, and dismantles the collective virulent power of pathogens.…”

Section: Introductionmentioning

confidence: 99%

Chitosan nanoencapsulation of flavonoids enhances their quorum sensing and biofilm formation inhibitory activities against an E.coli Top 10 biosensor

Omwenga

Hensel

Shitandi

et al. 2018

Phytochemicals have been found to be promising alternatives to conventional antibiotic therapies for the control of bacterial infections, as they may entail less selective pressure and hence reduce the development of resistance. This study involved examining the inhibition of biofilm formation and of quorum sensing (QS), and the cytotoxicity on mammalian cells of two flavonoids, quercetin and baicalein, in free form and associated into chitosan-based nanocapsules. This was done by use of a transformed E. coli Top 10 biosensor strain, while the cytotoxicity was evaluated on MDCK-C7 cells. In free form, application both flavonoids exhibited slight inhibitory activity on the QS response and biofilm formation, a scenario that was improved positively upon encapsulation with chitosan (Mw ∼115,000 g/mol and DA ∼42%). The association efficiency of 99% (quercetin) and 87% (baicalein) was determined, and each formulation had an average diameter of 190 ± 4 and 187 ± 2 nm, and zeta (ζ) potential of +48.1 ± 2.03 and +48.4 ± 3.46 mV, respectively. Both types of systems were stable against aggregation in M9 and MEM media. The in vitro release kinetics data of both flavonoids seemed to be similar with only ∼20% released over the first 5 h, or ∼10% over the first 4 h, respectively, with subsequent sudden release increase up to ∼40% in both cases. The free phytochemicals seemed to be cytotoxic to MDCK-C7 cells at higher doses, however, upon nanoencapsulation, a cytoprotective effect was evidenced. We have gained proof-of-principle of the advantages of encapsulation of two bioactive flavonoids.