How much ozone bactericidal activity is compromised by plasma components?

Abstract

Aims: Evaluation of bactericidal effect of different concentrations of ozone\ud when used (a) as a gas, or (b) dissolved in saline. The addition of hydrogen\ud peroxide or 4-hydroxynonenal dissolved in saline was also tested, as well as the\ud effect of human plasma.\ud Methods and Results: Staphylococcus aureus, methicillin-resistant Staph. aureus\ud (MRSA), and Pseudomonas aeruginosa, suspended in their culture media were\ud tested. While all bacteria suspended in protein-free saline were killed at high\ud ozone concentrations, they survived when as little as 5% human plasma was\ud present. Hydrogen peroxide was 100-fold less active than ozone and needed to\ud remain in contact with bacteria for at least 60 min. 4-hydroxynonenal\ud (2 lmol l)1) was inhibitory for proliferation of both Staph. aureus and MRSA,\ud but not for Ps. aeruginosa.\ud Conclusions: Ozone and the cascade of its derivative products are potent bactericidal\ud agents, but even small amounts of human plasma, hence of hydro- and\ud liposoluble antioxidants, in bacterial suspensions inhibit oxidation and protect\ud bacteria.\ud Significance and Impact of the Study: Any substantial in vivo cytocidal effect\ud of ozone and its derivatives can be excluded. On the other hand, topical and\ud continuous action of various ozone preparations remains valuable in a variety\ud of skin and mucosal infections

<i>In Vitro</i> Evaluation of Ozone Activity on Recent Clinically Isolated Bacterial Strains

“…In fact, these results are consistent with those of Burgassi et al [27], showing that the AHT enriched with ozone, even at highest ozone concentration (80 µg/ml), is not able to oxidize and destroy circulating bacteria in the blood.…”

“…Moreover, these authors suggested the incompatibility of using whole blood because it coagulates in the presence of a bacterial suspension [27].…”

“…The in vitro ozone bactericidal activity is compromised when applied to blood and blood derivatives [27].…”

Microbicidal Effects of Stored Aqueous Ozone Solution Generated by Nano-bubble Technology

“…Ozone can be easily consumed by oxidizable organic stuff and reductants present in its surroundings (13). Notably, in our in vitro experiments, NBOW that had been stored frozen for 1 year killed one of the most resistant bacteria, M. smegmatis, within 15 min; however, E. coli W3110 was not entirely killed even after a 60-min exposure.…”

Oxygen-Ozone Therapy in Medicine: An Update

“…In the past it has been claimed that ozone therapy allows seroconversion in HIV patients but we have not confirmed this result [30] . Our recent study [31] , aiming to evaluate how much ozone bactericidal activity is inhibited by the presence of plasma antioxidants, has confirmed that ozone cannot inactivate bacteria or/and viruses in vivo, particularly when pathogens are intracellular owing to the high content of GSH and antioxidant enzymes. Thus the previous dream to sterilize blood from all pathogens, especially viruses, is insubstantial because theoretically we would need such high ozone concentrations to kill blood cells before the intracellular viruses or parasites.…”