title: Enhanced activity of carvacrol against biofilm of Staphylococcus aureus and Staphylococcus epidermidis in an acidic environment.
abstract: Carvacrol is an antimicrobial monoterpenic phenol which occurs in many plant essential oils. The aim of this study was to investigate its activity at acidic pH on staphylococcal forming and yet established biofilms, with particular focus to improve its effectiveness on Staphylococcus epidermidis biofilm. The results showed that the subinhibitory doses (1/2, 1/4 and 1/8 MIC) of carvacrol determined a higher reduction of S. epidermidis biofilm formation than that observed at neutral pH. A potentiated inhibitory effect was also observed on established biofilm, carvacrol caused either a strong reduction of biomass (>50%) and bacteria attached to polystyrene (>7 log units). The images of scanning electron microscopy and the gas-chromatographic analysis support these results. The development of acidic formulations containing carvacrol could be an important tool to control the staphylococcal biofilm in the medical and food environment.
authors.affiliation: Pharmaco-Biological Department, University of Messina, 98168 Messina, Italy. anostro@unime.it
authors.forename: Antonia
authors.initials: A
authors.lastname: Nostro
authors.forename: Luigina
authors.initials: L
authors.lastname: Cellini
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Zimbalatti
authors.forename: Anna Rita
authors.initials: AR
authors.lastname: Blanco
authors.forename: Andreana
authors.initials: A
authors.lastname: Marino
authors.forename: Francesco
authors.initials: F
authors.lastname: Pizzimenti
authors.forename: Mara
authors.initials: M
authors.lastname: Di Giulio
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Bisignano
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001422:Bacterial Adhesion / Q000187:drug effects; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D000081007:Cymenes; D008826:Microbial Sensitivity Tests; D039821:Monoterpenes / Q000494:pharmacology*; D009822:Oils, Volatile / Q000494:pharmacology; D010938:Plant Oils / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology; D013212:Staphylococcus epidermidis / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D000081007:Cymenes; D039821:Monoterpenes; D009822:Oils, Volatile; D010938:Plant Oils; C073316:carvacrol