THE BETAINES AND THE VITAMINES 193 



example, when salts are formed with acids, and failure to obtain 

 marked curative results with these substances may therefore be attrib- 

 utable to absence of the above ring-structure in the preparations 

 administered. 



The antineuritic substances in an aqueous extract of yeast may be 

 removed therefrom by shaking up the fluid with fuller's earth. The 

 fuller's earth then becomes "activated" and carries with it all the 

 curative substances. An alkaline extract of this activated fuller's 

 earth was found by Williams and Seidell to exert a marked curative 

 effect, but on recrystallization the substance lost its antineuritic 

 properties and then was identified as Adenine. On heating to 180 

 in sealed tubes with alcohol, a portion of the antineuritic activity was 

 regained, and at the same time it acquired the power, which adeniue 

 does not possess, of yielding a blue color with Folin and Macallums' 

 "uric acid reagent." Williams and Seidell infer that the curative 

 substances in this instance is an isomeric modification of adenine. 



The instability of the curative substances and the minute propor- 

 tions in which they are present in antineuritic foodstuffs renders the 

 attainment of any definite conclusions a matter of exceptional difficulty. 

 In the meantime, however, and pending more exact knowledge of this 

 subject, very great care should be taken to avoid confusion by grouping 

 together essentially dissimilar substances of widely differing physio- 

 logical significance as "vitamines." Such procedure can only lead to 

 mystification, obscures the issue, and obstructs the progress of our 

 knowledge. The term "vitamine" should be definitely restricted to 

 those nitrogenous substances which are known to possess curative 

 action upon Polyneuritis. While a variety of other substances are now 

 known to exist, which, in relatively small amounts are essential to 

 health or growth, yet to group them all together as "vitamines" 

 simply deprives the name of its scientific significance. It is much 

 better to use the descriptive term "Accessory Foodstuffs," invented by 

 their discoverer, Gowland Hopkins, to include all dietetic factors which 

 are essential constituents of the diet for purposes other than the 

 provision of heat-units or the building-up of carbohydrates, fats and 

 proteins. The hydroxy-acids and other substances in fruits and 

 vegetables which act as Antiscorbutics or preventives of scurvy are 

 therefore " accessory foodstuffs" but they are not vitamines. We shall 

 make further reference to the various classes of accessory foodstuffs 

 in later chapters. 



Another deficiency-disease which probably depends upon lack of 

 vitamines, or of substances resembling those which are lacking in 

 polished rice, is Pellagra, a condition which is very common in districts 

 such as the Southern United States, where maize furnishes a large 

 proportion of the diet. Milling methods which involve total removal 

 of the pericarp of the grain are believed to be responsible for the 

 disease. Maize deprived of its outer covering has been shown to cause 

 polyneuritis in pigeons in the same way as polished rice. 

 1.3 



