Colorimetric MTT assessment of antifungal activity of D0870 against fluconazole-resistant Candida albicans

The in vitro antifungal activity of D0870 against eight isolates of flucona zole-resistant Candida albicans was compared with that of itraconazole, ket oconazole and miconazole. The colorimetric MTT [3-(4,5-dimethyl-2-thiazolyl ) -2,5-diphenyl-2H tetrazolium bromide] assay was used to assess the antifu ngal activities. The 50% minimum inhibitory concentration (MIC50) of D0870 was below 0.031 mu g ml(-1) for seven isolates and 0.25 mu g ml(-1) for one isolate. The activity of D0870 was superior to that of the other azoles. K etoconazole was the most effective azole next to D0870. Therefore, the new bis-triazole, D0870, is expected to be promising for the therapy of flucona zole-resistant candidosis. The present data also confirmed that the MTT ass ay may be useful for evaluation of resistance and detection of resistant C. albicans.