PRODUCTS OF HYDROLYSIS 



Gliadin, which contains much amide nitrogen and but little argi- 

 nine nitrogen, and excelsin, which contains little amide nitrogen and 

 very much arginine nitrogen, both gave results in very close agree- 

 ment with the calculation, while legumin and vicilin yielded slightly 

 more nitrogen by alkaline hydrolysis than that calculated. 



Most of the nitrogen came over in the first two distillations, 

 corresponding to the ease with which amide nitrogen is converted into 

 ammonia by caustic alkalies. The nitrogen subsequently coming off 

 as ammonia was evolved slowly in much the same way as from argi- 

 nine, although a little more quickly. The close agreement between 

 the results thus obtained and those calculated shows that these proteins 

 contain little or no nitrogen except the amide and one-half the argi- 

 nine nitrogen which can be thus converted into ammonia. 



The Undetermined Nitrogen of Protein Hydrolysis. 



The nitrogen of the protein, other than the amide and the basic 

 nitrogen, largely exists, so far as is now known, in the form of a-amino- 

 acids. It is not probable that all of the decomposition products of the 

 proteins are yet known, for attempts to determine the amount of each 

 of the known substances has in no case given a result which did not 



