Vitamines in Green Leaves. 



15 



The analysis of a crude product once purified by hot water 

 crystallization and dried in a vacuum desiccator gave: 



9 (1384) 

 Vitamines in green leaves. 

 By Thomas B. Osborne and Lafayette B. Mendel. 



[From the Laboratory of the Connecticut Agricultural Experiment 

 Station, and the Sheffield Laboratory of Physiological Chemistry 

 in Yale University, New Haven, Conn.] 



In view of the very scanty data recorded respecting the rela- 

 tive content of vitamine in green foods compared with other plant 

 and animal products which have been studied more in detail, we 

 have fed albino rats on diets containing, as the source of water- 

 soluble vitamine, spinach, cabbage, clover, timothy and alfalfa, 

 dried in their immature state. Far less dried spinach supplies 

 sufficient water-soluble vitamine to promote normal growth than 

 do whole wheat, soy beans, dried egg, meat, milk or potatoes. 

 Spinach leaves are much richer in the fat-soluble vitamine than 

 are most of the products used in our ordinary rations. Thus rats 

 fed for over 160 days, during which they consumed only 25 to 34 

 grams of spinach, have grown from 60 to 250 grams at a nearly 

 normal rate and have as yet shown no evidence of deficient nutri- 

 tion. Such quantities are not much larger than have heretofore 

 been considered to be necessary when butter fat supplied the fat- 

 soluble vitamine. A somewhat larger quantity of cabbage than 

 of spinach leaves is needed to promote normal growth. It prob- 

 ably also contains the fat-soluble vitamine. Timothy, clover 

 and alfalfa contain both vitamines, but further experiments are 

 needed to establish the relative amounts of these. Tests of a 

 large variety of tubers, stems, leaves and fruits are now in progress. 



If one may draw conclusions from the limited data at present 

 available, it seems that the green vegetables and fodders are richer 



Product 



Product 



Theory for primary. . 

 Theory for secondary 



34-20 

 34-50 

 34-6o 

 25-65 



As, # 



N, # 

 6.02 



6.13 

 6.45 

 9.65 



