JOHN A. KOLMER 1113 



of such mixtures might reach the Umit of the stronger dye, but in case of interaction 

 and precipitation between the two solutions the bactericidal efifect was actually de- 

 creased. Churchman has observed that mixtures of gentian violet and neutral acri- 

 flavin are bactericidal ; also mixtures of gentian violet and f uchsin, the gentian violet 

 for gram positive organisms, and the acriflavin and fuchsin for gram negative organ- 

 isms. In my experiments these observations have been confirmed, and in the mixtures 

 the identity of the dyes appears to be well preserved in that the bactericidal effects of 

 the mixture for gram positive organisms is approximately the same as shown by the 

 gentian violet alone in the same strength, and the bactericidal effect for gram negative 

 organisms is about the same as shown by the acriflavin or fuchsin alone in the 

 same strength. Churchman has advocated, therefore, the use of mixtures of these 

 kinds for the disinfection of tissues infected with both gram positive and gram neg- 

 ative organisms. 



IKFLUENCE OF HEAT UPON THE BACTERICIDAL ACTIVITY OF THE ANILIN DYES 



Since heat tends to increase the rapidity and rate of chemical reactions, it is to be 

 expected that hot solutions of the anilin dyes will prove more bacteriostatic and 

 bactericidal than cold solutions, and Churchman has furnished definite proof that 

 moderate heating (55° C. for one hour or 50° C. for one and one-half hours) increases 

 the penetrative power and bactericidal activity of gentian violet. Working with an 

 impeccable gentian violet-fast strain, he found gentian violet without effect at 22°- 

 35° C, but bactericidal when the solution of dye was heated to 50° C; control tests 

 showed that the effects were not due to heat alone or the dye alone, but to the com- 

 bination of heat plus dye. The phenomenon has not been explained, but the facts 

 established indicate that when the dyes are used for the treatment of localized infec- 

 tions by direct application, the solutions should be comfortably hot in order to secure 

 the enhanced bactericidal effects. 



SELECTIVE BACTERIOSTATIC AND BACTERICIDAL ACTIVITY OF THE ANILIN 

 DYES IN RELATION TO CHEMOTHERAPY 



As would be expected, the anilin dyes vary greatly in bactericidal activity and, as 

 shown above, may exert a stronger bacteriostatic and bactericidal activity for some 

 organisms than for others. Most of the anilin dyes in high concentration, say i : 100, 

 will kill practically all organisms irrespective of whether they are cocci or bacilli, 

 gram positive or gram negative, spore-formers or non-spore-formers, virulent or non- 

 virulent; but some of them show bactericidal and bacteriostatic properties for some 

 organisms in concentrations without effect upon other organisms. This is designated 

 as "selective activity" and bears a very intimate relationship to chemotherapy, since 

 it appears that the chemical constitution of the molecule influences these specific 

 properties. 



Churchman has especially contributed a most valuable series of studies bearing 

 upon this important topic of selective activity of the dyes. He has clearly proved that 

 gentian violet, magenta, and other dyes of the triphenylmethane series in general 

 possess a selective bacteriostatic and bactericidal activity for the gram positive organ- 

 isms, and especially the spore-formers, arbitrarily designated as "normal activity"; 

 curiously enough, however, these dyes may not inhibit the growth of the gram posi- 



