54 



THE PROTEINS 



THE WHEAT KERNEL. 



Oil examination both were found to contain some fat which could not be 

 wholly removed, as the substance had dried in a dense, horny form. The 

 residues which had separated from the solutions just described were next 

 washed by thoroughly intermixing with distilled water. The water was 

 found to dissolve some of the protein, which was subsequently precipitated 

 by the addition of a little sodium-chloride solution. After standing over 

 night this precipitate settled to the bottom of the vessel in a transparent 

 layer, from which the solution could be completely decanted. After treating 

 this substance with absolute alcohol, it formed a voluminous white, porous 

 mass, which was digested for some time with ether. From extract i 

 preparation 60 was obtained, weighing 12.4 grams ; from extract 2, united 

 with that from 3, preparation 61, weighing 8.6 grams. 



These preparations were found on analysis to have the following compo- 

 sitions : 



Preparations 60 and 61. 



The residues remaining after washing with distilled water were then 

 digested with alcohol of 0.820 sp. gr., which dissolved much of the 

 substance. After standing some time, the strong alcoholic solutions were 

 decanted from the residues and found to consist of milky liquids. The 

 addition of a few drops of 10 per cent sodium-chloride solution immediately 

 produced in each a very large, curdy precipitate, the liquids from which 

 they separated being left perfectly clear. From the solution from the first 

 extract, which was about one liter in volume, 32.26 grams of substance 

 were obtained after dehydration with absolute alcohol and digestion with 

 ether. This was marked preparation 62. From the second extract was 

 similarly obtained preparation 63, weighing 5.34 grams, and from the third 

 extract preparation 64, weighing 17.43 grams. The filtrates from 62 and 

 63 were found to be almost wholly free from protein, but that from 64 left 

 on evaporation a residue which, when freed from fat, weighed 7.53 grams, 

 preparation 65. 



