CHAPTER II 



VITAMIN B (Bi) 



Development of Knowledge of Vitamin B as an Antineuritic 



Substance 



We have seen that Eijkman, in his papers published from 1897 to 

 1906, clearly set forth his discovery that a diet of polished rice pro- 

 duces in fowls a condition of nutritional polyneuritis w^hich appears to 

 be essentially identical with typical beriberi in man, and that this disease 

 is due to the lack of a substance essential to normal nutrition, which 

 substance exists in the rice polishings (i.e., in the outer layers and 

 embryo of the rice kernel) as well as in other natural foods. After the 

 publication of the first of these papers, Grijns (1901) took up the 

 subject, confirmed Eijkman's earlier work and extended it to show that 

 the antineuritic or protective substance which Eijkman had demon- 

 strated to occur in rice, occurs also in legumes and in this case not 

 wholly in the outer layers of the seed. 



Failure to isolate the antineuritic substance from rice polishings 

 led Grijns to determine whether the heating of unpolished rice (or of 

 the phaseolus seeds) destroyed the protective power. Of four fowls 

 fed unpolished rice which had been heated at 120° C, two died of 

 polyneuritis after five or six months, while two remained well at the 

 end of eleven months. On polished rice fowls may be expected to 

 develop polyneuritis in about three weeks, while on unpolished and 

 unheated rice there should be entire freedom from the disease. Hence 

 Grijns concluded that heating at 120° C. destroyed much but not all of 

 the antineuritic substance of rice. Similarly heating the beans (phase- 

 olus) for one hour at 120° C. destroyed their antineuritic property 

 to such an extent that four fowls, fed such quantities of the beans 

 as would ordinarily protect them, all died of polyneuritis in from 33 

 to Z7 days. Grijns also observ^ed that fowls fed raw meat were pro- 

 tected, while those fed sterilized meat were not. 



Eijkman in 1906 described experiments designed to throw light 

 upon the chemical nature of the antineuritic substance. He found that 

 it was soluble in water, was dialyzable, and was not readily precipi- 

 tated from water solution by alcohol. In Eijkman's experiments the 

 antineuritic substance appeared to be entirely destroyed when unpol- 



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