IN VITRO EVALUATION OF THE SUSCEPTIBILITY OF CORYNEBACTERIUM PSEUDOTUBERCULOSIS TO DIFFERENT KINDS OF ANTISEPTICS AND DISINFECTANTS

ABSTRACT The aim of this study was to evaluate the in vitro effect of antiseptics and disinfectants against Corynebacterium pseudotuberculosis, and to define the growth curve of this microrganism inoculated in brain heart infusion broth plus 0.1% of Tween 80 (BHI + T), for 48 hours incubation. For the susceptibility test, evaluations were made using 10% iodine, 2.5% sodium hypochlorite, 5% potassium permanganate, Aseptol® liquid soap, and absolute ethyl alcohol (99.8%), by way of the disc-diffusion method. A sterile swab was immersed in a bacterial suspension and plated in Mueller-Hinton agar. Sterile discs were immersed in each solution to be tested and distributed on the agar surface. The results were obtained according to the inhibition circle diameter formed around the disc. For the growth curve determination, colonies were inoculated in a bottle containing BHI + T. Every 4 hours, 2 mL was withdrawn to evaluate the cell mass in a spectrophotometer, and 1 mL was taken to perform serial dilutions, blood agar base plating and counting of viable cells. It was observed that in order to reach the maximum concentration of C. pseudotuberculosis, close to 1,200 x 105 viable cells/mL, the inoculum must be maintained at appropriate incubation for a period of 28-40 hours. The sensibility test indicated