THE ANTISCORBUTIC VITAMINE 233 



Chick and Hume in the chapter on milk. Protein-free milk, prepared 

 by precipitation of casein with acetic acid at 50C., lactalbumin 

 removed by colloidal iron solution, and concentrated by freezing 

 (this may perhaps be a practical method of concentrating vitamine 

 C), exhibited, in amounts corresponding to 200 cc. of fresh milk, 

 only a very slight activity. An alcoholic extract of milk dried in 

 vacuum by us, possessed no activity in large doses, while the residue, 

 given in doses of 30 grams showed definite activity in some cases. 

 We then turned our attention to lime juice (I.e. 101). which was 

 universally known as a splendid antiscorbutic. For this reason we 

 were unable at that time, to explain why it was inactive in guinea 

 pigs. The same result was also obtained with the decomposed 

 phosphotungstate, prepared from lime juice. We were beginning to 

 doubt the identity of scurvy in guinea pigs with that in man, though 

 recently the situation was completely explained by Alice Henderson 

 Smith (621). In a historical sketch, she showed that the statements 

 as to the protective action of lime juice on scurvy were not true for 

 the sour limes of the West Indies used to-day, but were so for sweet 

 limes and lemons growing in the Mediterranean regions. 



The lime juice used to-day was shown to be inactive, but we 

 demonstrated the presence therein of vitamine B. Aside from this, 

 we isolated a terpene having the formula ds^Os, a purine base, 

 CcHrC^Ns (m.p. 282C.) and a substance from the histidine fraction, 

 melting at 188 to 189C. and having the formula C 9 H 18 O 6 N 2 . From 

 the choline fraction, a base was isolated as the double platinum salt, 

 which melted at 220C. and which was given the formula, C8H 15 2 N, 

 though a later investigation showed that the substance was identical 

 with stachydrine C 7 Hi 3 2 N. These data are quoted here because 

 it may later be shown that one of these substances is a cleavage 

 product of vitamine C. 



The experiments of Hoist and Frolich on the extractability of 

 vitamine C with alcohol, were later confirmed by Freise (622) on 

 turnips, as weU as by Freudenberg (623) . Subsequently, Harden and 

 Zilva (624) showed that when orange juice is freed from citric acid 

 by precipitation with calcium carbonate, and the mixture treated 

 with an equal volume of alcohol, filtered, and the filtrate concentrated 

 in vacuum at 37C., an active solution is obtained which, however, 

 loses its activity in time. If lemon juice is treated similarly, and 

 concentrated in acid reaction, an active residue is also obtained. 



