The MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay is a fast and reliable method for colorimetric determination of fungal cell densities

The entomopathogenic fungus Neozygites parvispora (Entomophthorales: Zygomy cetes) grows in vitro as irregularly rod-shaped hyphal bodies in a complex medium. In order to simplify the medium composition and determine growth-pr omoting compounds for the cultivation of this fungus, we were looking for a rapid and quantitative method to estimate the number of living cells in sm all volumes of liquid culture. A colorimetric method for the determination of cell densities using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetra zolium bromide] proved to be more accurate and timesaving than conventional hemocytometer counting.