1915] Clarence J. West ^55 



of the lipochrome of the cow body, chiefly on account of its ability 

 to form a Compound with one of the proteins of the blood. Xan- 

 thophyll apparently is not capable of forming such a complex. It is 

 much more soluble in bile than carotin^^ which accounts for its 

 appearance in the fat of the blood. While Palmer did not isolate 

 Carotin, it has been separated by Escher/ ^ who obtained 0.45 gm. of 

 pure pigment from 10,000 cow ovaries (corpus luteum). Carotin 

 has also been isolated from brown algae.^^ 



Lycopin. Lycopin is the coloring matter of the tomato. Ear- 

 lier investigators considered this pigment identical with carotin.^^ 

 Schunck,^^ by a careful spectro-analysis of the two Compounds, 

 showed that they were quite different and gave the tomato pigment 

 the name lycopin. The next year Montanari^^ confirmed the ob- 

 servations of Schunck; he recognized it as a hydrocarbon and 

 ascribed to it the formula, C52H74. 



Willstätter and Escher^^ found that it was isomeric with Carotin, 

 having the formula, C40H56. They used tomato conserve instead of 

 the fresh fruit for the preparation of the pigment. The conserve 

 was treated with 96 percent alcohol (to coagulate it), pressed, dried 

 and extracted with carbon disulfid. The concentrated extract was 

 precipitated with absolute alcohol and then recrystallized several 

 times from petroleum ether and carbon disulfid. The yield was 

 about 0.2 percent of the dry substance, i. e., 74 k. of conserve (5.6 k. 

 of dry powder), yielded 11 gm. of pigment. 



Lycopin forms light, or dark carmine-red, long, microscopic 

 prisms or hair-like needles, which cannot be mistaken for Carotin. 

 Dilute sol. in carbon disulfid have a hluish-red color, while those 

 of Carotin have a yellowish tinge. The two pigments show the 

 same color reactions with sulfuric and nitric acids. Lycopin differs 

 from Carotin in the following points: Lycopin absorbs oxygen 

 more rapidly and to a greater extent than does Carotin. Und'er 



14 Cf. Fischer and Rose : Ztschr. f. physiol. Chem., 88, 331, 1913. 



15 Escher : lUd., 83, 198, 1913. 



16 Willstätter and Page: Ann. d. Chem., 404, 237, 1914. 



17 A. Arnaud: Cotnpt. rend. acad. sc, 102, 1119, 1886. Kohl: Carotin und 

 seine physiologische Bedeutung in der Pflanze, p. 41. 



18 Schunck : Proc. Royal Soc, 72, 165, 1903. 

 löMontanari: Le stationi spcrm. agr. ital, 37, 909, 1904. 



20 Willstätter and Escher : Ztschr. f. physiol. Chem., 64, 47, IQIO- 



