title: Anti-Candida albicans effectiveness of citral and investigation of mode of action.
abstract: BACKGROUND
  Candidiasis is a mycosis caused by Candida species, which is of clinical importance due to the increase in resistant yeasts. Candida infection has been a serious health problem due to the inappropriate use of antibiotics. Therefore, it is necessary to study molecules with an antifungal action. Citral is a monoterpene with known pharmacological properties, including antimicrobial action.
  
  
  OBJECTIVE
  The aim of this work was to determine the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of citral and the probable mode of action.
  
  
  METHODS
  The MIC of citral was determined by the broth microdilution method using Sabouraud dextrose medium. Additionally, the interference of citral in cell wall (sorbitol assay) and the binding of citral to ergosterol and cholesterol were studied, carried out by broth microdilution method.
  
  
  RESULTS
  The MIC and MFC of citral were 512 and 1024 µg/mL, respectively. The MIC of amphotericin B was 1 µg/mL. The mechanism of action did not involve either the cell wall or ergosterol. However, the presence of cholesterol increased the MIC of citral to 1024 µg/mL, indicating there is some interaction between citral and cholesterol. Amphotericin B was used as the positive control, and it showed a high MIC in the presence of ergosterol (32 µg/mL), while in the presence of cholesterol MIC increased to 4 µg/mL.
  
  
  CONCLUSIONS
  Citral inhibits the growth of C. albicans. The probable mechanism of action did not involve the cell wall or ergosterol. Citral is able to interact with cholesterol. More studies are necessary to describe their effects completely.
authors.affiliation: Programa de Pós-Graduação em Produtos Naturais e Sintéticos Bioativos, Centro de Ciências da Saúde-CCS, Universidade Federal da Paraíba-UFPB, João Pessoa, Paraíba, Brasil. igaralima@yahoo.com.br
authors.forename: Igara Oliveira
authors.initials: IO
authors.lastname: Lima
authors.forename: Fernanda
authors.initials: F
authors.lastname: de Medeiros Nóbrega
authors.forename: Wylly Araújo
authors.initials: WA
authors.lastname: de Oliveira
authors.forename: Edeltrudes
authors.initials: E
authors.lastname: de Oliveira Lima
authors.forename: Everardo
authors.initials: E
authors.lastname: Albuquerque Menezes
authors.forename: Francisco Afrânio
authors.initials: FA
authors.lastname: Cunha
authors.forename: Margareth de Fátima
authors.initials: Mde F
authors.lastname: Formiga Melo Diniz
mesh_terms: D000080462:Acyclic Monoterpenes; D000666:Amphotericin B / Q000494:pharmacology; D000935:Antifungal Agents / Q000378:metabolism / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D002473:Cell Wall / Q000187:drug effects / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism; D004875:Ergosterol / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D039821:Monoterpenes / Q000378:metabolism / Q000494:pharmacology*; D013012:Sorbitol / Q000378:metabolism
chemical_list: D000080462:Acyclic Monoterpenes; D000935:Antifungal Agents; D039821:Monoterpenes; D013012:Sorbitol; D000666:Amphotericin B; D002784:Cholesterol; C007076:citral; D004875:Ergosterol