348 



THE VITAMINS 



Extraction with ether; saponification with alcohoHc potassium hydrox- 

 ide; separation of active material from the non-saponifiable fraction by 

 solution in cold pentane ; further concentration by extraction of pentane 

 solution with hot methyl alcohol, and of methyl alcohol solution with 

 petroleum ether; separation of inactive sterols by precipitation with 

 digitonin; saponification with hot 20 per cent alcoholic potassium hy- 

 droxide and second precipitation with digitonin ; further concentration 

 by solution in boiling methyl alcohol, followed by fractional distillation 



m vacuo. 



The general plan of procedure, approximate yields, and the activity 

 of the fractions thus obtained have been summarized by Evans and Burr 

 in the accompanying outline. 



OUTLINE OF FRACTIONATION OF 6 KILOS OF WHEAT GERM 



6 kilos wheat germ. 



I 

 Extracted with U.S. P. ethjr in Soxh- 

 let. 



I 



Ether extract. Active. Yield: 600 

 grams 10%. 



Saponified in the cold with 20% alco- 

 holic KOH. 



I 



Nonsaponifiable matter (N.S.M.). 

 Yield: 5%. Contains all the active 

 material. 



Crystallized from cold pentane. 



Pentane-soluble red oil. Yield: ?>?i% 

 of the N.S.M. Contains all the active 

 material. 



Extracted with hot MeOH. 



Ether-insoluble residue. Inactive. 



Soaps and glycerol. Inactive. 



Pentane insoluble solids. Sitosterol. 

 Yields: 66% of N.S.M. Inactive. 



Hot methyl alcohol solution. Active. 



Crystallized from cold MeOH. 



Cold MeOH solution. Active. 



>^ 



Distributed between dilute MeOH and 

 petroleum ether. 



Methyl alcohol insoluble residue. In- 

 active. Yield : 3% of N.S.M. 



i 

 Precipitate from cold MeOH. Almost 

 entirely inactive. Yield : 10% of 



N.S.M. 



