VIII, B, 3 Vedder and Williams : Vitamines in Rice 193 



3. Strongly alkaline reagents, such as sodium hydroxide, am- 

 monia, and barium hydroxide, destroy the neuritis-preventing 

 vitamine in its free or unhydrolyzed state, and the use of 

 these reagents must be avoided in endeavoring to isolate this 

 substance. 



4. Basic lead acetate does not precipitate the neuritis-prevent- 

 ing vitamine, and a considerable portion of this substance may 

 be recovered from the filtrate. 



5. The therapeutic properties of an alcoholic extract of rice 

 polishings are greatly altered by hydrolysis (treatment with 

 5 per cent hydrochloric or sulphuric acid). The unhydrolyzed 

 extract is not poisonous and is only slowly curative. The hy- 

 drolyzed extract is exceedingly poisonous in large doses and 

 promptly curative in small doses. 



6. We have confirmed Funk's observations by isolating a crys- 

 talline base from an extract of rice polishings by Funk's 

 method. This base in doses of 30 milligrams promptly cured 

 fowls suffering from polyneuritis gallinarum. 



7. Funk's base or vitamine is present in rice polishings in 

 considerable amounts, and only a very small portion of it can be 

 obtained by Funk's method. 



(1) Because the polishings themselves are incompletely ex- 

 tracted. 



(2) The greater part of this base is lost during the chemical 

 manipulations required by Funk's method as shown by the facts : 



(a) The curative action of this base, isolated, is from twenty- 

 five to fifty times weaker than the curative action of the original 

 hydrolyzed extract. 



(&) When fowls are fed on polished rice and given a daily 

 dose of this base in amounts corresponding to 10 cubic centi- 

 meters of the original extract, these fowls are not protected. 

 Ten cubic centimeters of the original extract or 10 grams of 

 polishings daily are amply sufficient fully to protect fowls. 



(3) Because Funk's method depends upon the use of barium 

 hydroxide, and we have shown that this reagent desti;oys this 

 base. 



8. Two groups of substances (purine bases, choline-like bases) 

 may be isolated from rice polishings in addition to Funk's base 

 and are capable of partly or wholly protecting fowls fed on 

 polished rice against polyneuritis gallinarum, but are incapable 

 of curing fowls that have already developed the disease. The 

 chemical nature of these two groups of bases requires further 

 investigation. 



