28 THE VITAMINS 



The following year Funk (1912a) reported the isolation of the 

 same or similar substances from yeast, milk, ox brains and lime 

 juice. The yeast was treated in two different ways. In the first, the 

 alcoholic extract was evaporated and the residue hydrolyzed with sul- 

 furic acid, after which the solution was treated as in the case of the 

 rice polishings by precipitation first with phosphotungstic acid and 

 then with silver nitrate and barium hydroxide. In the second method 

 the alcoholic extract after evaporation was extracted with water and 

 then precipitated with silver nitrate and barium hydroxide. This method 

 proved unsatisfactory as the bulk of the vitamin remained in the filtrate 

 and could not be precipitated except after hydrolysis. This was thought 

 to indicate that the vitamin is present in yeast in a combined form. 



Edie, Evans, Moore, Simpson and Webster (1912) after consid- 

 erable experimentation obtained from commercial fresh-pressed yeast 

 an active crystalline substance which they named toruline. 



In their method methyl alcohol slightly acidulated with hydrochloric 

 acid was used for the first extraction. This extract, after evaporation 

 to remove the alcohol, was set with plaster of Paris and the resulting 

 matrix ground to a fine powder and extracted on a shaking machine 

 with successive portions of the alcohol. Basic lead acetate and absolute 

 alcohol were used as reagents to separate the inactive constituents of 

 the extract, and silver nitrate and barium hydroxide to precipitate the 

 active substance. On decomposition of this precipitate by the usual 

 means, a small quantity of a brown sticky hygroscopic mass was ob- 

 tained, 3 milligrams of which is said to have been equivalent to 15 grams 

 of the original yeast. "A dose of 0.006 gram administered to a bird 

 with severe convulsions and lameness relieved the convulsions in four 

 hours ; the bird was flying strongly in 20 hours, and the lameness dis- 

 appeared in 48 hours. Two further doses of 0.003 gram were given 

 on the third and eighth days ; the bird appeared normal, and gained 

 weight on polished rice diet, but died on the fifteenth day without return 

 of lameness or convulsions." 



The crude material was insoluble in ether or acetone, very soluble 

 in water and soluble in alcohol, from which it could be crystallized 

 in feathery crystals. On analysis these crystals, to which the name 

 toruline was given, gave results corresponding to a formula C7H17N2OS 

 or C7Hi6N02(HN03). Assuming the presence of the trimethylamine 

 group the formula was further written as (CH3)3N.C4H702.HN03. 



In June 1912, Schaumann (1912a) described the preparation of a 

 crystallizable active base similar to that of Funk and proposed the 

 theory that this substance functioned as an activator in the body, 



