4-0 THE PROTEINS OE THE WHEAT KERNEL. 



THE PROTBINS OF THE WHEAT EMBRYO SOEUBEE IN SODIUM- 

 CHLORIDE SOLUTION. 



The Globulin of the Wheat Embryo. 



Wheat-germ meal treated with 10 per cent sodium-chloride brine forms a 

 dense jelly-like mass, from which it is nearly impossible to separate the 

 solution. 



With 3 per cent brine a manageable extract can be made by using from 

 six to ten times as much solvent as meal. Thus ioo grams of the meal 

 treated with 600 cc. of 3 per cent sodium chloride yielded in 15 hours 400 cc. 

 of clear filtrate. As has just been shown, the aqueous extract on dialysis, 

 in consequence of a change which affects leucosin, deposits a large amount 

 of protein, chiefly in the coagulated form. In order to obtain preparations 

 of the protein substance soluble in salt solutions, but insoluble in water, 

 which should be free from this coagulable albumin, 2000 grams of germ 

 meal were treated with 20 liters of 3 per cent sodium-chloride solution 

 heated to 70 , whereby the leucosin was coagulated and the salt-soluble 

 globulin brought into solution. The extract, neutral to litmus, was filtered 

 clear, at once saturated with ammonium sulphate, and the proteins thus 

 precipitated collected on a filter, dissolved in water, and the clear solution 

 dialyzed in running water. 



Protein matter separated on dialysis in spheroids, which, like many 

 other plant-globulins, united to a plastic mass on the bottom of the dia- 

 lyzer. This precipitate was dissolved in sodium-chloride solution and, after 

 filtering absolutely clear, dialyzed for 48 hours, the large precipitate which 

 separated allowed to settle, and the solution, which was nearly free from 

 protein, decanted. 



A portion of the precipitate was washed first with water, which rendered 

 it opaque and dense, then with dilute and finally absolute alcohol, and dried 

 over sulphuric acid. This weighed 5.22 grams, and is preparation 28. The 

 rest of the precipitate was completely dissolved in 125 cc. of 10 per cent 

 sodium-chloride solution. To this, water was added until its volume was 

 425 cc, thus making a sodium-chloride solution of nearly 3 per cent. From 

 this diluted solution a gummy deposit separated, from which the fluid was 

 soon completely decanted. The latter was further diluted with 325 cc. of 

 water and the precipitate which resulted allowed to settle to a viscid trans- 

 parent deposit. From this precipitate the solution was again decanted and 

 dialyzed for 48 hours, but not more than a trace of globulin was deposited. 

 The two precipitates produced by dilution formed preparations 29 and 30, 

 weighing respectively 11.4 grams and 8.15 grams. A part of each of these 

 preparations was set aside for analysis, and the rest, dissolved together in 10 

 per cent sodium-chloride solution, allowed to stand over night at 4 . The 



