HISTORICAL 



germ, and that the vitamin was adsorbed from acid solution on 

 fuller's earth and was precipitated by phosphotungstic acid. A. M. 

 Copping ^ was able to make further distinctions between the symptoms 

 of vitamin Bg and riboflavine deficiencies in rats ; the absence of 

 vitamin Bg produced dermatitis, with redness, swelling and oedema 

 of the paws, ears, etc., whilst absence of riboflavine produced skin 

 lesions, associated with loss of hair but unaccompanied by swelling 

 or inflammation. She showed that the acrodynia was cured by an 

 alcoholic extract of whole maize or wheat. C. E. Edgar and T. F. 

 Macrae ^ showed that rats did not grow optimally on a vitamin Bg 

 free diet to which riboflavine had been added, but did so when an 

 alcoholic extract of wheat germ or yeast was also added. Further 

 work showed that neither the factor adsorbed on fuller's earth (" eluate 

 factor ") nor the factor remaining in solution after fuller's earth 

 tieatment (" filtrate factor ") was effective alone, but that both were 

 needed in order to obtain a maximal response. They stated that the 

 " eluate factor " appeared to resemble Gy orgy's vitamin Bg, whilst 

 the " filtrate factor " was similar to Lepkovsky and Juke's factor 2. 



One of the reasons for confusion concerning vitamin Bg at this 

 stage of its history was that different workers used different sources 

 of the vitamin and different test animals, yet tended to assume that 

 the corresponding fractions were equivalent. Thus, when Edgar et al.^ 

 came to apply their fuller's earth treatment to liver extract, they 

 obtained fractions that behaved differently from the corresponding 

 fractions from yeast extract, and they had to resort to other methods 

 to secure parallel results. 



A clearer picture of the syndromes associated with each factor 

 was presented by Chick et al., ^^ who found that rats deprived of 

 riboflavine for a long time showed no increase in weight and developed 

 an eczematous condition of the skin affecting especially the nostrils 

 and eyes, that rats deprived of filtrate factor grew slowly and developed 

 poor coats, with matted fur that tended to become grey on the head 

 and shoulders, and that rats deprived of vitamin Bg developed derma- 

 titis and, later, epileptiform fits. These fits could be prevented and 

 cured by administration of 10 to 15 mg. of the vitamin per day.^^ 

 They were similar in appearance to fits observed in young pigs. 



References to Section 1 



1. J. Goldberger and R. D. Lillie, U.S. Puhl. Health Rep., 1926, 41, 201. 



2. T. W. Birch, P. Gyorgy and L. J. Harris, Biochem. J., 1935, 29, 2830. 



3. P. Gyorgy, Nature, 1934, 133, 498. 



4. C. A. Elvehjem and C. J. Koehn, /. Biol. Chem., 193=5, 108, 709. 



5. S. Lepkovsky and T. H. Jukes, ibid., 1936, 114, 109 ; 1937, 119» 



Ix ; /. Nutrition, 1938, 16, 197. 



297 



