VITAMIN E 



349 



Petroleum ether soluble. Active. 

 Yield: 13% of N.S.M. 



Sterols precipitated by digitonin. 



Dilute MeOH soluble. Inactive. Yield; 

 4% of N.S.M. 



Sterol-free orange oil. Yield : 2-3 

 grams. Active. 



Refluxed in hot 20% alcoholic KOH. 



Sterols from digitonide. Inactive. 



N.S.'M. Contains all of the active ma- 

 terial. 



Sterols again precipitated by digitonin. 

 I 



Fatty acids. Inactive. 



Sterol-free oil. Active. 



4^ 



Treated with boiling MeOH. 



Sterols. Inactive. 



Orange solution in MeOH. Active. 

 Yield: /OO-l.OOO mgs. (Proven ac- 

 tive in single doses of 5-10 mgs.) 



Distilled in vacuo. 

 I 



Residue insoluble in hot MeOH. 

 tive. Yield: 50-100 mgs. 



Inac- 



Fraction I. 

 Up to 200° C. at 0.8 mm. 

 Low activity. 38% of the 

 total. 



Fraction II. 

 200°-233° C. at 0.5 mm. 

 Highly active. 27% of 

 the total. 



Fraction III. 

 Residue above 233° 

 Highly active. 35% 

 the total. 



C. 

 of 



The final fraction is described by them as follows : "The final yellow 

 viscous oil does not develop crystals on long standing. It contains only 

 a trace of ash and no nitrogen, eulfur, phosphorus, or halogen. It is 

 remarkably potent. When 5 mg. are fed or injected under the skin of 

 a female of proved sterility at the inception of a new gestation, normal 

 litters of vigorous young are born and have been reared to adolescence. 

 Sister control rats invariably continue sterile. Furthermore, the daily 

 administration of only 0.3 mg. of this substance throughout the life 

 of the male results in the retention of complete normality when animals 

 are reared and held on pure foods, a normality proved by the weight 

 and histologic condition of the testis and by weekly functional tests 

 throughout the year, and controlled by the invariable development 

 of sterility at the end of three months in litter-mate brothers held on 

 the identical ration save for omission of the trace of vitamin." 



Evans and Burr consider that the best fractions are still not suffi- 

 ciently pure for trustworthy speculation as to the exact chemical nature 

 of the vitamin. 



