Abstract
Slant-N is the name of a new variety of DTM (Dermatophyte Test Medium) used to detect dermatophytes. This medium was studied with regard to the relation between the change in pH and the consequent change of the agar from yellow to red.
1) During growth of the dermatophytes, the medium became alkali. In the case of saprophytes, however, early changes in pH toward acidity preceded changes toward alkalinity.
2) When the change toward alkalinity reached pH 6.0 or pH 6.1, the color change from yellow to red was observed in all the cultures. The onset of the color change by the dermatophytes tested was always observed earlier than saprophytes. In case of these color changes enabled an early differentiation between the dermatophytes and the saprophytes.
3) Characteristic differences in the degree of the shifts in pH obtained with different species were classified into three types.
4) It was considered that the shifts toward alkalinity were produced by alkalinic metabolites from peptone, and the shifts toward acidity were produced by acidic metabolites from glucose in the medium.
