A research group led by Dentist Fumio Takizawa (graduate student), Associate Professor Hisanori Domon, and Professor Yutaka Terao of the Division of Microbiology and Infectious Diseases at Niigata University Graduate School of Medical and Dental Sciences has revealed that ozone ultrafine bubble water generated from air and water using ultrafine bubble technology not only kills bacteria but also degrades bacterial toxins. Since ozone is decomposed back to oxygen in the air, this technology is expected to be used as a safe and inexpensive disinfectant in the medical field, food industry, and nursing care facilities. The results were published in the international journal PLOS ONE on July 10.
Provided by Niigata University
Ozone gas can inactivate and kill viruses and bacteria and oxidatively decompose proteins; however, its use as a disinfectant has been hampered by its lack of solubility in water. Previously, the research group succeeded in generating ozone ultrafine bubble water using the "ultrafine bubble technology" to dissolve ozone produced from air in water as ultrafine-sized bubbles (approximately 100 nm). Since ultrafine-sized bubbles do not come to the surface, the technology allowed for the retention of ozone in the water for more than 24 hours, successfully keeping ozone water effective as a disinfectant at a practical level.
They examined the effects of ozone ultrafine bubble water on bacteria, causing food poisoning, and bacterial toxins. When a drug-resistant strain of Staphylococcus aureus was cultured in distilled or ozone ultrafine bubble water, the formation of colonies, an indicator of bacterial growth, was not observed in the ozone ultrafine bubble water. The ozone water was also found to degrade a type of enterotoxin produced by Staphylococcus aureus during growth.
Preventing food poisoning by enterotoxins was difficult because enterotoxins are not degraded even by heating at 100℃ for 30 minutes and so remain toxic after cooking. They also confirmed that ozone ultrafine bubble water degraded toxins produced by periodontopathic and pneumonia-causing bacteria and eliminated the toxin activities.
Ozone ultrafine bubble water is expected to find wide-ranging applications, such as disinfection and infection prevention, in clinical settings in developing countries because it can be produced in large quantities over a long period of time using air-derived ozone and water as raw materials with no environmental impact once a generator is installed. Moving forward, the research group plans to develop a device that can be used for various purposes, including disinfection and infection prevention in the medical field and hygiene control in the food industry, with the aim of commercialization. Not only in medicine but also in food processing
Terao said, "The usefulness of this disinfectant is that it can degrade and inactivate not only bacteria but also exotoxins produced by bacteria. Staphylococcus aureus can cause food poisoning even after heat sterilization. The reason is that enterotoxins are not inactivated even at 100℃ for 30 minutes and remain toxic. This disinfectant solution can break down enterotoxins and other bacterial exotoxins within minutes. Therefore, we believe that it can be useful not only in medicine but also in food preparation and processing."
Journal Information
Publication: PLOS ONE
Title: Effective degradation of various bacterial toxins using ozone ultrafine bubble water
DOI: 10.1371/journal.pone.0306998
This article has been translated by JST with permission from The Science News Ltd. (https://sci-news.co.jp/). Unauthorized reproduction of the article and photographs is prohibited.