title: Enhancement of the antibiotic activity of erythromycin by volatile compounds of Lippia alba (Mill.) N.E. Brown against Staphylococcus aureus.
abstract: BACKGROUND
  Lippia alba (Mill.) N.E. Brown, popularly known as "erva-cidreira," is commonly found in northeastern Brazil. The leaves tea is used to treat digestive disturbances, nausea, cough, and bronchitis.
  
  
  OBJECTIVE
  This work reports the chemical composition and erythromycin-modifying activity by gaseous contact against Staphylococcus aureus.
  
  
  METHODS
  The leaves of L. alba were subjected to hydrodistillation, and the essential oil extracted was examined with respect to the chemical composition, by gas chromatography-mass spectrometry (GC-MS), and the essential oil extracted was evaluated for antibacterial and antibiotic-modifying activity by gaseous contact.
  
  
  RESULTS
  The overall yield of essential oil obtained by hydrodistillation was 0.52%. The GC-MS analysis has led to the identification of the main components: geranial (31.4%) and neral (29.5%). It was verified that the essential oil interfered with erythromycin antibiotic activity against S. aureus ATCC 25923 was enhanced (221.4%) in the presence of 12% essential oil. The 3% essential oil increased the effect against S. aureus ATCC 25923 (41.6%) and S. aureus ATCC 6538 (58.3%).
  
  
  CONCLUSIONS
  The essential oil of L. alba influences the activity of erythromycin and may be used as an adjuvant in antibiotic therapy against respiratory tract bacterial pathogens.
  
  
  CONCLUSIONS
  The essential oil of L. alba influences the activity of erythromycin and may be used as an adjuvant in antibiotic therapy against respiratory tract bacterial pathogens.
authors.affiliation: Programa de Pós-Graduação em Bioprospecção Molecular - Laboratório de Pesquisas de Produtos Naturais - Universidade Regional do Cariri - CEP 63105-000 - Pimenta - Crato - Ceará - Brazil.
authors.forename: Helenicy N H
authors.initials: HN
authors.lastname: Veras
authors.forename: Adriana R
authors.initials: AR
authors.lastname: Campos
authors.forename: Fabíola F G
authors.initials: FF
authors.lastname: Rodrigues
authors.forename: Marco A
authors.initials: MA
authors.lastname: Botelho
authors.forename: Henrique D M
authors.initials: HD
authors.lastname: Coutinho
authors.forename: Irwin R A
authors.initials: IR
authors.lastname: Menezes
authors.forename: José Galberto M
authors.initials: JG
authors.lastname: da Costa