56 THE VITAMINS 



(c) comparatively speaking, this activated yeast vitamin is not a com- 

 plete supplement to a polished rice diet. There are apparently two 

 so-called vitamins associated with rice polishing, one which cures 

 polyneuritis and one which produces weight, and of these two, the 

 Seidell yeast vitamin preparation contains chiefly the curative fraction, 

 along with a small per cent of the other." This is of interest in con- 

 nection with the later work of Williams and Waterman (1927) and 

 of Randoin and Lecoq (1927d, e). 



Drummond (1917) attributed losses in purification not so much 

 to instability of the vitamin as to its ready adsorption by colloidal pre- 

 cipitates. "Further proof that this is probably the explanation of the 

 great loss which is so often encountered in the isolation of the sub- 

 stance is to be found in the fact that whenever in the course of the 

 fractionation recourse to precipitation is made, the precipitate, particu- 

 larly if bulky and flocculent in nature, will usually carry down the 

 majority, if not all, of the active substance from solution." The greater 

 difficulty in tracing the growth-promoting than the antineuritic vitamin 

 during fractionation was attributed by Drummond to the fact that 

 much smaller quantities of the extracts were required to improve the 

 condition of polyneuritic pigeons than to cause an appreciable increase 

 in the body weight of rats. 



McCollum and Simmonds (1918) studied the solubility and sta- 

 bility of vitamin B, using white beans or wheat embryo as sources of 

 the vitamin. Young rats were fed a diet of purified food substances 

 (casein, salt mixture, agar-agar and dextrin) together with 5 per cent 

 of butterfat to supply an abundance of vitamin A. The rats were 

 confined to this diet for about five weeks until they had either become 

 stationary in weight or were declining with evidences of paralysis. The 

 material to be tested was then added to the diet, the animals continuing 

 to decline or responding with growth according as the material was 

 deficient or rich in vitamin B. This method was considered to show 

 within two weeks whether the preparation under investigation con- 

 tained vitamin B in significant amounts. As tested by these criteria, 

 it was shown that vitamin B is not extracted directly from beans, wheat 

 germ or pig kidney by ether, benzene or acetone, but is readily ex- 

 tracted in great part by alcohol (95 per cent). McCollum and Sim- 

 monds concluded that: "The probability that there should be two or 

 more physiologically indispensable substances in what we term water- 

 soluble B, both or all of which should show the same solution relations 

 with three solvents, is relatively small and lends support to our view 

 that the substance which protects animals against polyneuritis is the 



