Prestoblue resazurin dye

In vitro antifungal activity was measured according to National Committee for Clinical Laboratory Standards (NCCLS) recommendations.³⁶ The minimum inhibitory concentration (MIC) was determined by means of the serial dilution method in 96-well plates with YM (1% maltose extract, 0.2% yeast extract, and 0.4% agar) as the test medium. Amphotericin B was used as the positive control. Test compounds were dissolved in DMSO and serially diluted in growth medium. Visual end point and optical density readings of microplate wells were measured relative to positive and negative controls. The strains were incubated at 25 °C, and the MICs were determined at 24 h for C. albicans ATCC 10231 and at 48 h for C. neoformans H99. Viability was determined with the aid of a plate reader using PrestoBlue resazurin dye (Life Technologies) as the viability indicator. The spectrophotometric MIC value was defined as the lowest concentration of a test compound that resulted in a culture with a density consistent with 100% inhibition when compared to the growth of the untreated control.

In vitro antifungal activity was measured according to National Committee for Clinical Laboratory Standards (NCCLS) recommendations (Anonymous 2008 ). The minimum inhibitory concentration (MIC₁₀₀) was determined by means of the serial dilution method in 96-well plates containing YM broth as the growth medium. Amphotericin B was used as the positive control. Test compounds were dissolved in DMSO and serially diluted in growth medium. Visual endpoint and optical density readings of microplate wells were measured relative to positive and negative controls. The strains were incubated at the indicated temperatures, and the MIC₁₀₀ values were determined at 48 h for C. neoformans H99. Viability was determined with the aid of a plate reader using PrestoBlue® resazurin dye (Life Technologies) as the viability indicator and by direct inspection of the wells under a stereomicroscope. The spectrophotometric MIC₁₀₀value was defined as the lowest concentration of a test compound that resulted in a culture with a density consistent with 100% inhibition and no detectable growth as observed by microscopy when compared to the growth of the untreated control.