title: Pimenta pseudocaryophyllus inhibits virulence factors and promotes metabolic changes in Candida yeast.
abstract: BACKGROUND
  This is the first study to examine the in vitro susceptibility and the expression of virulence factors in Candida species in the presence of Pimenta pseudocaryophyllus (Gomes) L.R. Landrum (Myrtaceae), a Brazilian plant known as paucravo. Additionally, the mechanisms of action of the crude ethanol extract and the ethyl acetate and aqueous fractions of this plant were investigated.
  
  
  METHODS
  The in vitro susceptibility of Candida was tested using the broth microdilution method, whereas an XTT reduction assay was used for biofilms. Adherence was determined by counting the number of yeast cells that adhered to 100 oral epithelial cells, and hyphal formation was verified in the hyphal induction medium M199. Flow cytometry with propidium iodide and FUN-1 was performed to assess the mechanism of action.
  
  
  RESULTS
  The results revealed that the crude ethanol extract and the ethyl acetate and aqueous fractions of P. pseudocaryophyllus inhibited the growth of Candida isolates at a minimal inhibitory concentration (MIC) ranging from 64 to 256 µg/mL, whereas the 50% sessile minimal inhibitory concentration (SMIC50) ranged from 512 to >1,024 µg/mL. Adherence and hyphal formation were significantly reduced in the presence of the crude ethanol extract and both fractions. Although cell membrane injury was detected, the predominant mechanism of action appeared to be the alteration of yeast metabolism, as demonstrated by flow cytometry.
  
  
  CONCLUSIONS
  Our results indicated that antifungal activity reduced the expression of virulence factors in yeast via the alteration of yeast metabolism, suggesting that the crude extract of P. pseudocaryophyllus and its fractions may contain novel antifungal agents.
authors.affiliation: Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil.
authors.forename: Flávio Ezeddinne
authors.initials: FE
authors.lastname: El Assal
authors.affiliation: Unidade de Ciências Exatas e Tecnológicas, Universidade Estadual de Goiás, Anápolis, GO.
authors.forename: Joelma Abadia Marciano
authors.initials: JA
authors.lastname: Paula
authors.affiliation: Unidade de Ciências Exatas e Tecnológicas, Universidade Estadual de Goiás, Anápolis, GO.
authors.forename: Leonardo Silva
authors.initials: LS
authors.lastname: Capeletti
authors.affiliation: Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil.
authors.forename: Fernando Yano
authors.initials: FY
authors.lastname: Abrão
authors.affiliation: Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil.
authors.forename: Fábio Silvestre
authors.initials: FS
authors.lastname: Ataídes
authors.affiliation: Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil.
authors.forename: Fabyola Amaral da Silva
authors.initials: FA
authors.lastname: Sá
authors.affiliation: Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil.
authors.forename: Carolina Rodrigues
authors.initials: CR
authors.lastname: Costa
authors.affiliation: Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil.
authors.forename: Orionalda de Fátima Lisboa
authors.initials: Ode F
authors.lastname: Fernandes
authors.affiliation: Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil.
authors.forename: Lúcia Kioko Hasimoto
authors.initials: LK
authors.lastname: Souza
authors.affiliation: Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil.
authors.forename: Maria do Rosario Rodrigues
authors.initials: Mdo R
authors.lastname: Silva
mesh_terms: D000935:Antifungal Agents / Q000302:isolation & purification / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects; D002175:Candida / Q000187:drug effects* / Q000472:pathogenicity; D005434:Flow Cytometry; D006801:Humans; D007928:Lethal Dose 50; D008826:Microbial Sensitivity Tests; D027841:Pimenta / Q000737:chemistry*; D010936:Plant Extracts / Q000494:pharmacology*; D037521:Virulence Factors / Q000037:antagonists & inhibitors*
chemical_list: D000935:Antifungal Agents; D010936:Plant Extracts; D037521:Virulence Factors