The work of Churchman1 on gentian-violet has shown that this substance possesses the peculiar property of inhibiting in high dilution the growth of grampositive organisms. This fact has been confirmed by Krumwiede and Pratt,2 and applied by Petroff3 in his medium for isolation of cultures of the tubercle bacillus from sputum. As most of the skin saprophytes are gram-positive, it occurred to us that gentian violet might be of value in restraining the growth of skin contaminants in cultures during the isolation of the pathogenic molds of the skin and hair, provided the substance should prove to be non-inhibiting for the molds themselves.
A preliminary series of experiments was undertaken using four molds of widely varying growth characteristics to determine in a general way the effect of gentian-violet on their growth. The organisms, all of which were isolated in this laboratory, selected were: (1)
FARLEY DL. THE USE OF GENTIAN-VIOLET AS A RESTRAINER IN THE ISOLATION OF THE PATHOGENIC MOLDS. Arch Derm Syphilol. 1920;2(4):459–465. doi:10.1001/archderm.1920.02350100047006