title: Amphypterygium adstringens anacardic acid mixture inhibits quorum sensing-controlled virulence factors of Chromobacterium violaceum and Pseudomonas aeruginosa.
abstract: OBJECTIVE
  Quorum sensing (QS) is a process of bacterial cell-cell communication that controls a large number of systems affecting pathogenicity. Interrupting this communication system can provide nonvirulent pathogenic bacteria. The aim of this study was to evaluate the anti-quorum sensing (anti-QS) potential of an anacardic acids mixture isolated from Amphipterygium adstringens, a medicinal plant known as "cuachalalate", to prevent the onset of bacterial infections as an alternate to antibiotics.
  
  
  METHODS
  Initially we investigated the anti-QS activity of A. adstringens hexane extract (HE) by the inhibition of violacein production in Chromobacterium violaceum. From the active HE, an anacardic acid mixture (AAM) was obtained. The anti-quorum sensing activity of AAM was investigated by the rhamnolipid and pyocyanin production constraint as well as decrease of elastase activity, all being quorum sensing-controlled virulence factors expressed in the pathogenic bacteria Pseudomonas aeruginosa.
  
  
  RESULTS
  HE induced a 91.6% of inhibition of the violecin production at 55 μg/mL concentration, whereas AAM showed 94% of inhibition at 166 μg/mL. In both cases, inhibition of violacein production did not affect the viability of the bacterium. AAM inhibited pyocyanin (86% at 200 μg/mL) and rhamnolipid (91% at 500 μg/mL) production in a dose/response form and decrease the elastase (75% at 500 μg/mL) activity in P. aeruginosa without affecting its development.
  
  
  CONCLUSIONS
  Because an anacardic acids mixture isolated from A. adstringens demonstrated anti-QS, it could be further exploited for novel molecules to treat the emerging infections of antibiotic-resistant bacterial pathogens.
authors.affiliation: Colegio de Postgraduados, Campus Montecillo Estado de México, Mexico.
authors.forename: Israel
authors.initials: I
authors.lastname: Castillo-Juárez
authors.forename: Rodolfo
authors.initials: R
authors.lastname: García-Contreras
authors.forename: Norma
authors.initials: N
authors.lastname: Velázquez-Guadarrama
authors.forename: Marcos
authors.initials: M
authors.lastname: Soto-Hernández
authors.forename: Mariano
authors.initials: M
authors.lastname: Martínez-Vázquez
mesh_terms: D027926:Anacardiaceae / Q000737:chemistry; D048729:Anacardic Acids / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002861:Chromobacterium / Q000187:drug effects* / Q000254:growth & development / Q000472:pathogenicity; D024881:Drug Resistance, Bacterial; D006017:Glycolipids / Q000037:antagonists & inhibitors / Q000378:metabolism; D007211:Indoles / Q000037:antagonists & inhibitors / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000254:growth & development / Q000472:pathogenicity; D011710:Pyocyanine / Q000037:antagonists & inhibitors / Q000378:metabolism; D053038:Quorum Sensing / Q000187:drug effects*; D037521:Virulence Factors / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D048729:Anacardic Acids; D000900:Anti-Bacterial Agents; D006017:Glycolipids; D007211:Indoles; D010936:Plant Extracts; D037521:Virulence Factors; C418382:rhamnolipid; D011710:Pyocyanine; C063155:violacein
keywords: Amphipterygium adstringens; Anacardic acid; Anti-quorum; Antimicrobial plant; Quorum-sensing inhibitors