Antimicrobial and antibiofilm in vitro effect of oxygen-ozone gas against Staphylococcus aureus

Equine endometritis is the primary reproductive pathology that causes significant economic losses due to subfertility, and Staphylococcus aureus (S. aureus) is one of the main infectious agents. Oxygen-ozone is a gas with high oxidative potential that promotes the destruction of bacterial cells, modulates inflammation, and induces a regenerative response, making it an adequate alternative treatment for endometritis. This study aimed to evaluate the antimicrobial and antibiofilm effects of the oxygen-ozone gas on microbial cultures of S. aureus. Closed ozonated systems were used in three experiments. The S. aureus cultures were then treated with the oxygen-ozone mixture by either bubbling the gas through the Tryptic Soy Broth with the bacteria or directly exposing the plates to the gas while testing different amounts and lengths of the exposure. In the first experiment, it was observed that the bactericidal effect on the planktonic state increased after 10 min, and showed a better result at 60 min. In experiment two a bactericidal effect with exposure for 10 min to concentrations of 19 and 41 μg/mL was observed. After exposure for 20 min, a concentration of 10 μg/mL was effective in killing the strain in the planktonic state. Antibiofilm effects were observed at concentrations of 19, 41, and 70 μg/mL. Therefore, it can be concluded that S. aureus showed sensitivity to oxygen-ozone gas, which also promoted an antibiofilm effect on the studied strain.