title: Inhibition of Staphylococcus aureus by oleuropein is mediated by hydrogen peroxide.
abstract: The inhibition of Staphylococcus aureus by oleuropein is shown to be largely due to hydrogen peroxide production by oleuropein. The reaction is initiated by noninhibitory levels of hydrogen peroxide present as a result of tryptone oxidation in the underlying medium. Inhibition is abolished by catalase and anaerobic incubation conditions, and the effect of tryptone can be replicated by exogenous H2O2. S. aureus strains with reduced catalase activity show greater sensitivity to oleuropein. A mechanism for hydrogen peroxide production is proposed. Inhibition is not entirely due to H2O2, since some organisms with similar sensitivity to H2O2 as S. aureus were resistant to oleuropein, suggesting that there may be a cooperative effect between H2O2 and oleuropein itself.
authors: School of Biomedical and Molecular Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK.
authors: Dario
authors: D
authors: Zanichelli
authors: Tim A
authors: TA
authors: Baker
authors: Michael N
authors: MN
authors: Clifford
authors: Martin R
authors: MR
authors: Adams
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D002374:Catalase / Q000096:biosynthesis; D015169:Colony Count, Microbial; D004347:Drug Interactions; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods*; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D057888:Iridoid Glucosides; D039823:Iridoids; D011714:Pyrans / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development
chemical_list: D000890:Anti-Infective Agents; D057888:Iridoid Glucosides; D039823:Iridoids; D011714:Pyrans; C002769:oleuropein; D006861:Hydrogen Peroxide; D002374:Catalase