Figure 1.

Evaluation of the borreliacidal activity of disulfiram (in DMSO and cyclodextrin) with doxycycline as control. A 4-day-old, B. burgdorferi log phase culture of B. burgdorferi was incubated for four days with disulfiram (Dis-DM), disulfiram (Dis-CD) and doxycycline (Doxy) at the same drug concentrations of 100 μM to 0.625 μM respectively. After a five-day incubation, bacteria cell viability was assessed by (A), by direct counting using dark field microscopy and (B), by SYBR Green-I/PI assay using fluorescent microscopy. (C), Representative images were taken using SYBR green-fluorescent stain (live organisms) and propidium iodide red-fluorescent stain (dead organisms) at 200× magnification. All these experiments were repeated at least three times (n = 6). Error bars represent standard errors.