Fig. 6.

Impact of the XTT manufacturer on assay results. The reference strain C. albicans DAY185 was grown overnight in YPD medium plus uridine at 30°C, and cells were enumerated with a hemocytometer. After a 24-h biofilm formation period, biofilms were treated with serial dilutions of amphotericin B for 24 h. Absorbance at 492 nm was measured following 1 h of incubation with XTT (0.75 mg/ml) from Sigma or Biotium. Student's t test was used to compare Sigma XTT with Biotium XTT at each amphotericin B concentration. *, P < 0.05.