title: Rosmarinus officinalis L. essential oil and its majority compound 1,8-cineole at sublethal amounts induce no direct and cross protection in Staphylococcus aureus ATCC 6538.
abstract: In this study, the inhibitory efficacy of Rosmarinus officinalis essential L. (ROEO) and 1,8-cineole (CIN) in inhibiting the growth and survival of Staphylococcus aureus ATCC 6538 and the induction of direct and bacterial cross protection (lactic acid pH 5.2; NaCl 100 g/L; high temperature 45°C) were evaluated following exposure to sublethal and increasing amounts of these treatments in meat broth. All of the concentrations of the ROEO and CIN examined in this study (minimum inhibitory concentration [MIC], 1/2 MIC, and 1/4 MIC) inhibited the viability of S. aureus throughout the 120 min of exposure. The overnight exposure of S. aureus to sublethal amounts of both ROEO or CIN in meat broth did not result in direct or cross protection. Cells progressively subcultured (24-h cycles) in meat broth with increasing amounts of ROEO or CIN showed no increased direct tolerance. These results reveal the antimicrobial efficacy of ROEO and CIN for use in food conservation systems as anti-S. aureus compounds given their efficacy at inhibiting bacterial growth, in addition to their lack of induction for the development of homologous and heterologous resistance.
authors.affiliation: Laboratory of Food Microbiology, Department of Nutrition, Health Sciences Center, Federal University of Paraíba, João Pessoa, Brazil.
authors.forename: Nelson Justino
authors.initials: NJ
authors.lastname: Gomes Neto
authors.forename: Isabelle da Silva
authors.initials: Ida S
authors.lastname: Luz
authors.forename: Adassa Gama
authors.initials: AG
authors.lastname: Tavares
authors.forename: Vanessa Gonçalves
authors.initials: VG
authors.lastname: Honório
authors.forename: Marciane
authors.initials: M
authors.lastname: Magnani
authors.forename: Evandro Leite
authors.initials: EL
authors.lastname: de Souza
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D003511:Cyclohexanols / Q000494:pharmacology*; D000077591:Eucalyptol; D005516:Food Microbiology; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability / Q000187:drug effects; D039821:Monoterpenes / Q000494:pharmacology*; D009822:Oils, Volatile / Q000494:pharmacology*; D010938:Plant Oils / Q000494:pharmacology; D027542:Rosmarinus / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000187:drug effects*; D013997:Time Factors
chemical_list: D000890:Anti-Infective Agents; D003511:Cyclohexanols; D039821:Monoterpenes; D009822:Oils, Volatile; D010938:Plant Oils; D000077591:Eucalyptol