RESULTS OF ANALYSIS 75 



any other protein ; its analysis shows that it is distinct from legumin. 

 It contains no glycine and more glutamic acid than legumin. A 

 similar protein does not exist in the vetch. 



Amandin contains 19 per cent, of nitrogen; the high content in 

 arginine and ammonia serve to explain this high figure. The proteins 

 of the peanut are rich in lysine, and in this respect are of great value 

 for improving a diet containing protein which is deficient in this unit. 



The high figure for valine in Foreman's analysis of the protein of 

 linseed is remarkable. 



Gliadins and Glutelins. 



There is a very marked difference in the composition of the two 

 proteins found in cereals. Those amino acids, which are absent in the 

 alcohol-soluble protein, are present in the other protein, which is 

 soluble in dilute alkali. The mixture (gluten) of these proteins in the 

 grain, therefore, gives all the amino acids present in other proteins. 



The gliadins are very like one another in composition. They are 

 distinguished from other proteins by their high content in glutamic 

 acid, proline and ammonia, their low content in arginine and histidine ; 

 lysine is absent from zein, but is present in wheat gliadin in very small 

 amount. On account of the high content in proline and ammonia 

 Osborne suggested the name of prolamines for this group ; the group 

 name gliadins has been preferred by the British workers. 



Wheat-gliadin and rye-gliadin show no great differences, and it 

 seems probable that they are the same protein. Zein of maize differs 

 from them in containing no glycine and no tryptophan and also in con- 

 taining more leucine and less glutamic acid. The high tyrosine con- 

 tent found by Kutscher does not seem to be correct. Kafir, largely 

 grown in U.S.A., contains kafirin as its chief protein, which resembles 

 zein, but contains lysine and tryptophan. Hordein contains more 

 proline than any other protein. 



Wheat-glutenin and the other glutelins seem to contain all the 

 amino acids which have been isolated. The analysis of rice by the 

 Japanese workers is for the whole grain and not for the isolated pro- 

 tein ; they found that the husk of the grain also contained protein, 

 and that the proportions of the constituent amino acids were different. 

 Data for the di-amino acids in oryzenin have been published by 

 Osborne, Van Slyke, Leavenworth and Vinograd [1915]. 



