832 X. THE VITAMIN K GROUP 



One unusual plant source which has recently been reported is the berry of the 

 European mountain ash or rowan (Sorbus aucuparia L.)/^ The concentra- 

 tion of vitamin Ki in alfalfa is sufficiently high so that a potent preparation 

 has been made commercially by oil extraction of the dried leaves. ^^ 



Most bacteria contain vitamin K2/^ On the other hand, molds, yeasts, 

 and fungi have practically no vitamin K of either type. Putrefied animal 

 and plant materials usually possess abundant amounts of vitamin K2, due 

 to bacterial growth. Intestinal bacteria of most of the higher animals can 

 synthesize this vitamin readily. For this reason the feces have been shown 

 to contain abundant quantities of vitamin K. This has been demon- 

 strated in the case of chick feces, "^^ and of dried human feces. Vitamin K2 

 can be separated from human feces by extraction with alcohol or petroleum 

 ether. '*~^^ Vitamin K2 appears in the rumen of the cow, even on vit- 

 amin-K-deficient diets.'**' 



Most animal products contain very little of this vitamin; when present 

 the type of vitamin depends upon the previous diet. Vitamin Ki pre- 

 dominates when abundant amounts of this type of vitamin K are ingested; 

 however, definite proportions of vitamin K2 may occur. One would expect 

 the latter when the bulk of the vitamin K stored can be traced to that syn- 

 thesized by the intestinal bacteria. Hog liver^' seems to be the most 

 abundant animal source, while chicken livers^^-^^ and the livers of rats^' 

 contain very little of this vitamin. Egg-yolk has considerable amounts of 

 vitamin K when sufficient vitamin is present in the diet.^^ None can be 

 demonstrated in egg albumen. There is also an appreciable amount of the 

 antihemorrhagic vitamin in cow milk if the cow has received an adequate 

 amount of it in her food.''* 



3. Structure of the K Vitamins 



(1) Consiilution of Vitamin Ki 



Karrer and Geiger** proved, on the basis of elementary composition and 

 molecular weight, that the empirical formula of vitamin Ki is C31H46O2. 

 The molecular weight was found to be 450 as determined by potentiomctric 

 titrations with sodium hydrosulfite. Vitamin Ki was proved to be 2- 



^2 G. Y. Shinowara, J. De Lor, and J. W. Means, /. Lab. Clin. Med., 27, 897-907 

 (1942). 



" S. Musher, U. S. Patent No. 2,282,796 (May 12, 1942). 



" J. Almquist, C. F. Pentler, and E. Mecchi, Pror. Soc. Exptl Biol. Med., 38, 336- 

 338 (1938). 



« H. J. Almquist and E. L. R. Stok.stad, /. Nutrition, 12, 329-335 (1936). 



« L. W. McElrov and H. Goss, /. Nutrition, 20, 527-540 (1940). 



« H. Dam and F. Sch0nhevdcr, Biochem. J., SO, 897-901 (1936). 



« P. Karrer and A. 6eiger, Helv. Chiin. Acta, 22, 945-948 (1939). 



