'78 i?. H. ChitteMflen — Gaseoses, Casein Dyspeptone, 



at 100° C, and the residue so obtained treated again in a like man- 

 ner with the same strength of acid, a comparatively large amount of 

 casein antialburaid was obtained, which unlike the dyspeptone from 

 a gastric digestion, was only slowly soluble in dilute sodium carbon- 

 ate. Freed from any adhering soluble products by treatment with 

 several litres of a vigorous gastric juice for two days at 40° C, it still 

 dissolved slowly in dilute sodium carbonate. By long contact with 

 a one per cent, solution of the alkaline carbonate it finally dissolved, 

 leaving but a small residue. From this solution, the antialbumid 

 was reprecipitated by hydrochloric acid, and after thorough washing 

 with water, it was again dissolved in sodium carbonate, the fluid 

 made exactly neutral and then dialyzed until all chloride was re- 

 moved. After concentration of the fluid and precipitation with alco- 

 hol, etc., the antialbumid was dried and analyzed. It contained 18 

 percent, of ash. The ash-free substance contained 54*4 per cent, of 

 carbon, 68 per cent, of hydrogen, and 14"8 per cent, of nitrogen; 

 showing thus a much higher percentage of carbon, and a lower per- 

 centage of nitrogen than the dyspeptone formed by pepsin-hydro- 

 chloric acid. 



Both casein antialbumid and dyspeptone are dissolved with more 

 or less readiness by alkaline solution of trypsin and are converted 

 by long warming at 40° C. into a peptone-like body, presumably 

 antipeptone. 



II. Caseoses ;— from experiments by Charles Norris, Jr., Plt.B., and 



C. A. Tuttle, Ph.B. 



In a previous study of the caseoses formed in pepsin digestion,* we 

 were much impressed with the peculiar behavior of protocaseose 

 towards acids. Unlike the proto bodies from other proteids pre- 

 viously studied, aqueous solutions of the substance gave heavy pre- 

 cipitates with dilute acids. Protocaseose, as then separated, was 

 readily soluble in 0-4 per cent, hydrochloric acid, but addition of 

 stronger acid invariably produced a decided precipitale, soluble, 

 however, in a still larger excess of acid. This peculiarity rendered 

 the protocaseose an object of some interest to us, and further study 

 of the conditions favoring its formation in gastric digestion has 

 shown us that, apparently, the nature of the body precipitated by 

 saturation with salt, as well as the body precipitated by salt-satu- 

 rated acetic acid is modified by the strength of the pepsin solution, 



* Chittenden and Painter. Studies from Laboratory of Physiological Chemistry, 

 vol. ii, p. 195. 



