82 



KARL FOLKERS 



TABLE XII 

 Activity of Folic Acid Conjugates in Pernicious Anemia 



O 



li 



RC 



N N 



< 



Effective 

 (Spies, 1946) 



■\ NHCH, ^^\^ 

 N OH 



N 



R — three glutamic acid moieties 



Pteroyltriglutamic acid 



(Fermentation L. casei factor) 



O 

 R'C^ 



N N 



X\/Anh, 



\ NHCH, 



Inefifective 

 (Welch and associates, 1946) 



N OH 



N 



R =z seven glutamic acid moieties 



Pteroylheptaglutamic acid 

 (Vitamin Be conjugate) 



The liver extract was fractionated with acetone and passed over 

 acid-washed permutit and fractionated again with water-acetone mix- 

 tures (Table XIII). The crystals which were obtained appeared to be 

 neutral in character and showed a positive test for primary aliphatic 

 amino groups. The material was active in doses of 20-60 mg. for 

 causing an increase in the white cell count and neutrophiles when given 

 intravenously to malnourished patients with leukopenia. These investi- 

 gators believed that this product might be related to the extrinsic factor 

 for pernicious anemia. 



During 1 936-1 941 Wulzen and Bahrs studied the growth and disease 

 of planarian worms when the mashed tissues of guinea pigs which 

 were maintained on experimental diets were fed to these worms. The 

 growth of the worms was a measure of a change in the mammalian 



