The Disinfectant Action of Certain Bacterial Stains

Abstract

Among the earliest workers to note the disinfectant action of bacterial stains were Cornil and Babes,' two botanists, who found, in working with methyl violet, that it possessed a toxic action on various bacteria. In 1890 Stilling published results of work with a dye, probably a mixture of dyes which he called pyoktannin. His experiments, none too carefully performed, with B. subtilis, B. anthracis, and M. aureus, led him to the conclusion that the dye was a general bacterial poison, its antiseptic strength being three times that of bichlorid of mercury, and that the action of the dye was directly proportional to the strength of the dilution used, and to the time of the exposure. Spina2 in his article speaks of the use of indigo and methylene blue in the staining of culture media. He uses, however, in ioo c.c. of culture media only a few drops of a sterile saturated solution of the dye, this, of course, being too high a dilution to have any active disinfectant or bactericidal action, even if the stain itself possessed such a property. Spina also notes that in this dilution bacteria have a marked reducing action upon the stain used. HuberJ shows the effect of diffused light upon broth cultures of streptococci stained with eosin and erythrosin and exposed to the light for different periods of time as follows: Streptococcus exposed to diffused light for I hr. showed growth on first and second day in unstained broth, eosin stained broth, and erythrosin stained broth. Exposure for 3 and 6 hrs. resulted in growth on first and second day in unstained broth, but no growth in eosin stained broth or erythrosin stained broth. The control which was not exposed showed growth in all 3 broths. Results with B. diphtheriae were practically the same except that there was only a slight growth in the 3-hr. exposure on the second day. Conradi and Drigalski4 deal principally with crystal violet in culture media which inhibited numerous cocci and bacteria, but had no effect upon B. coli and B. typhosus. A number of organisms belonging to the subtilis group are also mentioned among those that grew on their crystal violet plates. Penzolds also notes a definite bactericidal action of certain bacterial stains. Another work of interest and. of more recent date is that of DeWitt.6 In these experiments with the various dyes, two drops of a per cent solution of each dye are