Antiviral Ability of Ozone Generator Developed by Faculty of Engineering Ubon Ratchathani University

Abstract

Ozone consisted of 3 atoms of oxygen. It is a relatively unstable gas because of a weak bond joining an extra oxygen atom to oxygen gas. Consequently, it usually causes oxidation leading to growth inhibition of microorganisms. Currently, ozone generators for sterilization have been developed commercially. The faculty of Engineering, Ubon Ratchathani University has developed an ozone generator under the project “Innovations for medical supports during COVID-19 pandemic”. This study aims to examine the ability of the ozone generator developed by the Faculty of Engineering, Ubon Ratchathani University to inhibit viruses. In this study, coliphage, a virus infecting Escherichia coli, was used as a representative of viruses. To examine the effect of exposure time to ozone on inhibitory ability of the ozone generator against coliphage, ten microliter of coliphage with the concentration of 10⁷ pfu/ml was spotted onto BHI agar and then subjected to ozonation for 30, 60, 90 and 120 min. After ozonation, BHI agar having ozonated coliphage was overlaid with soft BHI agar containing E. coli and then incubated at 37^oC for 24 h. It was found that ozone treatment for 60 min or more could completely inhibit coliphage. To examine the effect of viral load on inhibitory ability of the ozone generator against coliphage, ten microliter of coliphage with the concentrations of 10⁷, 10⁶, 10⁵, 10⁴, 10³, 10² and 10 pfu/ml was spotted onto BHI agar and then subjected to ozonation for 30 min. After ozonation, BHI agar having ozonated coliphage was overlaid with soft BHI agar containing E. coli and then incubated at 37^oC for 24 h. It was found that ozone treatment for 30 min could completely inhibit coliphage with the concentrations of 10⁵ pfu/ml or less. From this study, it was suggested that the most effective exposure time for the application of the ozone generator to completely inhibit viruses would be at least 60 min.