Figure 5. The impact of environmental stressors on reduction of germinated Clostridium difficile spores.

Eight log₁₀ colony forming units (CFU) of C. difficile VA17 spores were exposed to 1 mL of germinants in a test tube for 30 minutes under ambient conditions (22°C, aerobic). Germinated spores were washed 3 times and then 10 μL (6 log₁₀CFU) of the spore suspension was inoculated into the empty well of a glass slide (dry conditions) or a well containing nutrient free agar (moist conditions). The glass slides were placed on the bench top (aerobic conditions) or in an anaerobe containment system (anaerobic conditions) for 24 hours. The temperature was maintained at 22°C for the duration of the experiment. After incubation, the spores were recovered from the slides and the log₁₀CFU reduction of spores was determined. The means of data from triplicate experiments are presented. Error bars indicate standard error.