PROTEIN DISSOCIATION IN THE INTESTINE 53 

 t 



numerous studies prosecuted by Abderhalden, London and 

 their associates, 8 left no doubt as to the constant presence 

 of considerable amounts of aminoacids in the contents of the 

 intestine (even if dissociation is apparently not complete), 

 and too of notable quantities of polypeptoids. 9 The intes- 

 tinal contents differ decidedly in this from the gastric con- 

 tent, which, as a rule, shows no aminoacids at all or at most 

 only traces. (In the instances in which these substances do 

 occur in the stomach, as in the omasum of ruminants, the 

 possibility of the existence of ferments in the food itself must 

 be considered, 10 as it has been indicated from the work 

 of the Ellenberger Institute that under certain circumstances 

 autolytic ferments may relieve the animal intestine in part 

 of its work of digestion and may act as substitutes for the 

 body enzymes.) u 



The later advances in the chemistry of proteins, espe- 

 cially Emil Fischer's ester method, formol-titration of 

 aminoacids, etc., harmonize with these studies. The ester 

 method cannot be applied to the determination of amino- 

 acids in the intestinal content unless special provisions (as 

 refrigeration during the estering process, etc.) are em- 

 ployed, as in the process of estering it is possible that 

 aminoacids may be split off from proteid substances. 12 



It is impossible to deny that proteid substances are separ- 

 ated into their final derivatives ; but it is another question 

 whether resorption normally occurs only after such ad- 

 vanced dissociation. Three possibilities must be taken into 

 consideration. In the first place absorption of an impor- 



8 Baumann, Funk, Kautzsch, v. Korosy, Medigreceanu, Oppler, Reemlin. 

 Literature: O. Prym, 1. c. 



9 E. Aberhalden, Zeitschr. f. physiol. Chem., 74, 436, 1011. 



10 E. Abderhalden, W. Klingemann and Th. Pappenhusen, Zeitschr. f. 

 physiol. Chem., 11, 411, 1911. 



11 W. Grimmer ( Ellenberger's Lab.), Biochem. Zeitschr., 4, 80, 1907; cf. 

 Literature, there appended. 



12 B. 0. Pribram (Vienna), Zeitschr. f. physiol. Chem., 71, 472, 1911; 72, 

 504, 1911. 



