NUTRITION — OSBORNE. 219 



in the embryo of this seed aud is probably one of its ' ' tissue ' ' proteins, in 

 contrast to the "reserve" proteins of the endosperm, of which gliadin and 

 glutenin form the chief part. 



Glycocoll is not given among the products of hydrolysis of gliadin, for 

 careful efforts to detect its presence in the preparation used for this analysis 

 failed. Another hydrolysis of another lot of gliadin prepared in essentially 

 the same waj^ did yield 0.02 per cent of glycocoll whose identity was cer- 

 tainly established. This small quantity was most probably due to a small 

 admixture of glutenin in the gliadin used for this determination, which may 

 have been dissolved in very small amount by the large quantity of dilute 

 alcohol used for extracting the gliadin. A contamination of this prepara- 

 tion with 2 per cent of glutenin would have sufficed to give the amount of 

 glycocoll found. The amount of prolin yielded by gliadin is larger than 

 that as yet obtained from any other protein, those coming nearest being the 

 albuminoids spongin and gelatin. As the amount of prolin from glutenin is 

 relatively high, the wheat proteins as a whole, so far as we yet know, are 

 particularly rich in this peculiar amino-acid. 



Glutaminic acid is the chief constituent of the endosperm proteins of this 

 seed, gliadin jdelding more of this acid than any protein yet examined and 

 very much more than the average of our food proteins. The average amount 

 of glutaminic acid from the total protein matter of this seed is more than 30 

 per cent. The yield of ammonia is likewise relatively very high, more than 

 4.5 percent for the total protein, while the aggregate amount of hexone 

 bases is correspondingly small. In respect, therefore, to the proportion of 

 several of their decomposition products the wheat proteins present marked 

 and important differences from other food proteins. 



During the year in which work under this grant was carried out it has 

 been necessary to devote a great deal of time to studying the methods 

 employed and assuring ourselves of the accuracy of our work. As a great 

 many processes were used this has necessarily delayed the work of the first 

 year, for many of these processes require a long time for their execution as 

 well as great care. The experience which we have acquired has now put us 

 in a position to obtain results much more rapidly. 



Grant No. j^g {$^,000). — Under this grant work has been continued along 

 the same lines as under Grant No. 263. Large quantities of protein prepara- 

 tions have been made and are now ready for hydrolysis. These include several 

 from leguminous seeds, nuts, and oil seeds. A complete quantitative analysis 

 of the decomposition products of phaseolin, the principal protein of the white 

 or kidney bean, has been made and the results will soon be published. A 

 similar analysis of excelsin is well advanced. 



A study of the methods for the quantitative determination of the basic 

 decomposition products of proteins has been made and the bases determined 

 in several proteins, the results of which we expect to be soon able to publish. 



