Ozone Inactivation of Streptococcus Faecalis and Staphylococcus
Aureus in Water as Models of Gram (-) Bacteria
I. Lezcano, R. Pérez-Rey, E. Sánchez, Ch. Baluja, C. Alvarez.
Ozone Research Center, Cuba.
Ozone is a potent germicidal agent. Inactivation kinetics of
Pseudomonas aeruginosa and Escherichia coli towards ozone in
water, as models of Gram (-) bacteria, were studied. For this
purpose, water suspensions of 104 – 106 CFU/ml of Pseudomonas
aeruginosa and Escherichia coli isolated from polluted water and
Pseudomonas aeruginosa ATCC 27853 and Escherichia coli ATCC 25922,
were prepared in sterile conditions and treated in a 100 mL bubble
reactor with ozone, achieving concentrations from 0.3 to 2.61 mg
of dissolved ozone/L of water, in contact with microorganisms.
Total inactivation obtained by this procedure varied from 1.04 to
19.23 minutes depending on the bacterial resistance and the ozone
concentration applied. The ATCC strains showed to be more
sensitive than the environmental isolates; Pseudomonas aeruginosa
was the most resistant wild strain. First order inactivation
kinetics respect to both the concentrations of ozone and
microorganisms were found, resulting an overall second order
Source: 2nd International Symposium on Ozone Applications
Havana, Cuba – Mach 24-26, 1997.