Exploring the Antibacterial Effects of Ozonated Oils in Medicine: A Study on Escherichia coli Inhibition

Ozonated oil has a long tradition in medical therapy. Here, the results from previous studies regarding the antibacterial effects of ozonated oils were compared. In addition, the aim of this study was to further examine the antibacterial activity against Escherichia coli for two different ozonated oils, in regard to the ozone exposure time and amount. Using agar dilution, the minimum inhibitory concentration of the oils was studied. For all of the tested concentrations with the agar dilution method, bacterial growth was observed. Furthermore, agar dilution was combined with spread-plating to determine the inhibition zone with and without the emulsifier. The emulsifier-free and emulsifier-containing experiments with agar dilution and spread-plating did not result in an inhibition of bacterial growth by ozonated oils. Moreover, the bacteria were exposed to the oils for various intervals before being grown on either solid or liquid medium to determine the time-dependent antibacterial effects of the ozonated oil. For both media, the results were compared to non-ozonated oil and NaCl solution as a negative control. The bacteria in the solid medium were already completely inactivated after 5 min of exposure with the ozonated oil. For the liquid medium, also shorter exposition times were investigated. After 1 min, there was no inhibition in the ozonated oils with the liquid medium. After 5 min, the bacterial growth in the ozonated oils was significantly reduced in the liquid medium.