Effects of ozonated water on Candida albicans   oral isolates

Forty-nine C. albicans freshly isolated strains and C. albicans ATCC 18804 were included in the study. Initially, suspensions containing 5 x 108 viable cells/ml were prepared. This suspension was submitted to a concentration of 3.3 mg/ml of ozone for 20s, 40s, 60s, 80s, 100s 120s, 140s, 160s, 180s and 300s. Before the experiment and also after each period of exposition, 0.1 ml of dilutions of the final suspension was plated on Sabouraud dextrose agar and incubated at 37°C for 24-48 h. After this period, the number of colony forming units was calculated. Data were statistically analyzed by Pearson's correlation test. A reduction of the microorganism's concentration during the contact time with ozone was observed. Complete inactivation was observed only for standard strain after 5 min. Freshly isolated C. albicans strains showed higher resistance to ozone. A linear correlation between the logarithm of yeast concentration and period of contact was found in both cases, being the linear correlation coefficients significant in the experiments.