ON THE BEHAVIOR OF KERATIN SULFUR AND 



CYSTIN SULFUR, IN THE OXIDATION OF 



THESE PROTEINS BY POTAS- 



SIUM PERMANGANATE. I* 



TH. LISSIZIN 

 (Laboratory of Medical Chemistry, University of Moscow, Russia.) 



Introduction. Previous researches on the products f ormed f rom 

 proteins in general and from keratin in particular, by the action of 

 potassium permanganate, give almost no indication of the f ate of the 

 sulfur in this oxidation process. Since it is now known, as a result 

 of Maly's^ investigations, that the total sulfur of egg-white remains 

 in oxy-proto sulfonic acid, during permanganate oxidation, it is 

 natural to ask: how does the sulfur of keratin, and of other sul- 

 fur-yielding albuminoids, behave in such oxidation? Following 

 a Suggestion of Prof. Dr. VI. Gulewitsch, I have undertaken the 

 oxidation of human hair and of cystin, and have investigated the 

 oxidation-products in relation to the sulfur content. 



Experimental. A. First I determined the sulfur-content of 

 dry, fat-free, human hair. 



I. 0.4106 gm. of human hair was fused with a mixture (1:8) 

 of potassium hydroxid and potassium nitrate, over a small alcohol 

 flame. The fused mass was dissolved in water; the Solution was 

 acidified with hydrochloric acid, after the addition of a few drops 

 of bromin water, and evaporated to dryness on a water-bath; the 

 residue was dissolved in water, filtered, precipitated in the usual 

 way with barium chlorid, and the precipitate ignited and weighed. 

 The amount of barium sulfate obtained was 0.1661 gm. (0.02282 

 gm. sulfur). The hair contained, therefore, 5.56 percent of sulfur. 



Then the sulfur-content of the oxy-proto sulfonic acid derived 

 from the hair was determined. For this purpose I took 200 gm. of 



♦Translated from the author's manuscript, in German, by Dr. Edgar G. 

 MiHer, Jr. 



iMaly: Sitzungher. d. k. Acad. d. Wiss., 1885, xci (II Abteil), p. 157. 



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