44 



THE) PROTEINS f OF THE WHEAT 



Having determined the composition of this globulin-like protein and also 

 that of the albumin, it became clear that several preparations obtained from 

 the aqueous extract were mixtures of these two substances, thus showing 

 the globulin to be present to some extent in the aqueous extract. 



As noted on page 24, when 2000 cc. of an aqueous extract of about 650 

 grams of the meal were dialyzed in running water for 4 days a dense tur- 

 bidity was formed, which could not be removed by filtration. This, however, 

 on adding a little hydrochloric acid, was converted into a precipitate, which 

 was readily dissolved by adding sodium chloride sufficient to make a 3 per 

 cent solution, and was precipitated from this solution by dialysis. 



Preparation 38, weighing 9 grams, was thus obtained, which, dried at 1 10, 

 had a composition which corresponds pretty nearly with that of a mixture of 

 60 per cent of the globulin with 40 per cent of leucosin, except that the 

 amount of sulphur found was somewhat greater than that calculated. The 

 analysis is shown in the following table : 



Preparations 38 and jp. 



After heating another portion of the same aqueous extract to 65 for some 

 time and filtering off the coagulum, the filtrate was dialyzed for 5 days into 

 alcohol and the precipitate thereby produced filtered out and exhausted with 

 water. The residue of protein matter coagulated by alcohol, weighing 6.7 

 grams and marked preparation 39, was then dried at 110 and analyzed with 

 the results shown in the preceding table. 



This analysis corresponds quite nearly with that of a mixture of 40 per 

 cent of the globulin with 60 per cent of leucosin. 



