344 



KiRKWOOD AND GiES : Chemical Studies 



the name of phytovitellin. The composition they gave for it is in 

 general accord with that of edestin (nitrogen content = 18.40 per 

 cent.), and as they obtained it partly crystallized in octahedra, Os- 

 borne * has lately suggested that the substance is edestin. The 

 results we have obtained confirm Osborne's deduction. 



The proteose to which we have already alluded was obtained 

 from the globulin filtrate. The latter was freed from traces of 

 globulin by the coagulation method, the hot filtrate evaporated to 

 a small bulk on the water-bath and the proteose precipitated and 

 purified by the usual method, t About four grams were obtain- 

 able from fifteen nuts. The product contained both proto and 

 deutero forms. Some heteroproteose was also detected in the 

 products formed on dialysis and a trace of dysprotose was 

 obtained. 



The following results for nitrogen content in the ash-free sub- 

 stance were obtained by the Kjeldahl method : 



Percentage of Nitrogen in Cocoa Proteose 



These results differ only slightly from those reported by Chit- 

 tenden and Setchell.| This difference may be explained by the 

 fact that mixtures of proteoses have been analyzed in each case 

 by Chittenden and Setchell, and by us. Their preparation of pro- 

 teose contained 18.25 per cent, of nitrogen. 



In his volume entitled Digestive Proteolysis, Chittenden gives 

 the analytic results for eleven different proteids and the proteoses 

 derived from them (page 67). For seven of these the nitrogen of 

 the corresponding proteose is somewhat higher than that of the 

 original proteid. Analysis of our own preparations has shown the 

 percentage of nitrogen to be greater in the proteose than in the 

 globulin, a result in accord with the majority rule just noted. 



* Osborne : Journal of the American Chemical Society, i8 : 13. 1896. 



f Mac Dougal : Practical Text-book of Plant Physiology, 164. 1901. 



J Chittenden and Setchell : Quoted by Chittenden, Digestive Proteolysis, 32. 1S95. 



