2(5H)-Furanone, epigallocatechin gallate, and a citric-based disinfectant disturb quorum-sensing activity and reduce motility and biofilm formation of Campylobacter jejuni

Abstract

Brominated furanone and epigallocatechin gallate (EGCG) are naturally occurring polyphenolic compounds that can be derived from sources such as Delisea pulchra algae and green tea, respectively. These compounds may have potential health benefits and antimicrobial properties. Biofilm formation and bacterial motility are virulence factors that seem to be involved in the autoinducer 2 (AI-2)-mediated quorum sensing (QS) response of Campylobacter. In this study, the anti-QS activities of 2(5H)-furanone, EGCG, and a citric-based disinfectant were tested against Campylobacter jejuni. The minimal bactericidal concentration (MBC) was determined by a microdilution method, and the AI-2 activity was measured by bioluminescence. For motility tests, subinhibitory concentrations of each compound were mixed with semisolid Muller Hinton agar. Biofilm formation was quantified in broth-containing microplates after staining with safranin. The MBC of tested compounds ranged from 0.3 to 310 μg/mL. Subinhibitory concentrations of all of the antimicrobial compounds significantly decreased (19 to 62 %) the bacterial motility and reduced biofilm formation. After treatment with EGCG, furanone, and the disinfectant, AI-2 activity was decreased by 60 to 99 % compared to control. In conclusion, 2(5H)-furanone, EGCG, and the disinfectant exert bactericidal effects against C. jejuni and disturb QS activity and reduce motility and biofilm formation. These compounds may be naturally occurring alternatives to control C. jejuni.

Anti-quorum sensing activity of phenolic extract from Eugenia brasiliensis (Brazilian cherry)

“…Castillo et al (2015) have shown that epigallocatechin gallate (EGCG), a compound extracted from green tea, inhibited motility in Campylobacter jejuni. Packiavathy et al (2011) found that Cuminum cyminum extracts inhibited motility in Proteus mirabilis, P. aeruginosa PAD1 and S. marcescens.…”

The Antimicrobial Effect of a Commercial Mixture of Natural Antimicrobials Against Escherichia coli O157:H7

“…The ethanol wash and centrifugation steps were repeated three times (Al-Shabib et al 2016;Huston et al 2004). EPS was quantified using the colorimetric phenol-sulphuric acid method as previously described (DuBois et al 1956) Autoinducer-2 (AI-2) assay Todetermine whether AI-2 production in the E. coli O157 EDL 933 is affected by sub-inhibitory concentrations of the novel antimicrobial, the autoinducer-2 (AI-2) assay was performed as previously described (Castillo et al 2015;Duan and March 2010). Briefly, approximately 7 Log CFU/mL of E. coli O157 were inoculated and cultured in LB broth with 0.5% (w/v) glucose containing 0, 0.0625 and 0.125% of the antimicrobial at 37°C for 6 h. Vibrio harveyi BB170 was grown overnight at 30°C with agitation in Autoinducer Bioassay medium (AB) and diluted 1∶3,000.…”

Phenolic Compounds with Anti-virulence Properties

“…EGCG at sublethal concentrations also inhibits motility and biofilm formation of Campylobacter jejuni, a foodborne pathogen which is one of the main causes of gastrointestinal infections worldwide [46]. In this case, the mechanism involved in biofilm inhibition is related to QS inhibition [46].…”