Efeito inibitório de óleos ozonizados sobre o crescimento de Staphylococus aureus

Abstract

Objective: To evaluate, in vitro, the antimicrobial activity of ozonized essential oils against the bacteria Staphylococcus aureus. Methods: In vitro experimental study, in which, through the inhibition test in a 96-well plate, the inhibitory effect on the microbial growth of the bacteria S. aureus was observed, based on the action of ozonized essential oils of rosehip, coconut, olive, sunflower, Melaleuca, grape seed and clove. The oils were tested maintaining their physical-chemical parameters, such as appearance, color, purity, odor, density and refractive index, described by the manufacturer. Among the oils used, only two were ozonized by hand before testing, the others were ozonized by the manufacturer. Additionally, the death kinetics test – Time Kill was carried out to determine the time (1h to 6h) of inhibitory action of the oils. For the tests, inoculum were prepared from cultures on Brain Heart Infusion agar with 24h growth, prepared in RPMI medium and adjusted to a 0.5 McFarland scale and spectrophotometer at 625nm (absorbance 0.11-0.15). Results: In total, 14 variations of ozonized oils were analyzed, of which 5 showed an inhibitory action on the bacteria S. aureus, namely: Rosehip (EBPM-OXI3), Rosehip (nanonized EBPM-OXI3), sunflower (Phylozon), olive (Phylozon) and sunflower (Mophderm). Among the artisanal ozonized oils, only sunflower oil (Mophderm) showed inhibitory activity. In the evaluation of death kinetics, only Rosehip oils (EBPM-OXI3 and nanonized EBPM-OXI3) showed inhibition of bacterial growth within 6 hours, in which from the second hour of interaction with the oils there was no colony growth. Conclusions: Ozonized essential oils have potential as antimicrobial agents against S. aureus, since among the oils tested, five of them stood out for their effectiveness. Kill kinetics analysis revealed that rosehip oils were particularly effective, inhibiting bacterial growth in just two hours of exposure. These findings suggest a promising potential of ozonized oils, especially rosehip derivatives, as antimicrobial agents against S. aureus. These findings are relevant in the context of developing alternative and complementary therapies to combat bacterial infections.