AN INVESTIGATION OF AMERICAN GENTIAN 



VIOLETS 



REPORT OF COMMITTEE ON BACTERIOLOGICAL TECHNIC 

 Prepared by II. J. CONN, Chairman 

 Received for publication June 9, 1922 



This report is a continuation of the work on American stains 

 that has recently been published in this journal (Conn, 1922). 

 In this earlier report fairly definite conclusions were reached in 

 regard to fuchsin and methylen blue but the work on gentian 

 violet was regarded as being unfinished. 



Gentian \iolet is a term which does not refer to any definite 

 chemical compound, but rather to a mixture of dyes of a cer- 

 tain group. The term was apparently originated by Griibler 

 and is not recognized in the dye industry or in the textile industry. 

 The dyes in the mixtures sold as gentian violet all belong to the 

 pararosanilin series but at the present time the different manu- 

 facturers and dealers nearly all sell different mixtures of these 

 dyes under the name of gentian violet. This being the situation, 

 the best use for the term gentian violet seems to be as a generic 

 designation for any violet pararosanilin which has the general 

 staining properties recognized as belonging to Griibler's gentian 

 violet. 



As mentioned in the earlier report the pararosaniUn base has 

 the formula 



H.N.CeH.C(OH)<g|;:Ng^ 



The six hydrogen atoms of this formula which are in the amino- 

 groups can be replaced by a methyl group, an ethyl group or a 

 benzyl group. The most commonly known compounds of the 

 pararosanilin series contain in these positions 4, 5, and 6 methyl 

 groups respectively, and are known as the tetramethyl, penta- 



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