558 VI. CAROTENOIDS AND RELATED COMPOUNDS 



berry tree),^^^ Ananas comosus (sativus) (pineapple), ^^^ Vaccinium viiis idaea 

 (cowberry) ^"^ Prunus persica (peach), '"^ and rose hips of Rosa eglanteria 

 (red rose sweetbriar).^^^ The occurrence of this pigment in seeds is indi- 

 cated by its isolation from wheat germ oil {Triticiim spp.).^^°~^^^ 



Animal products are a source of lutein, but in this case its presence is 

 adventitious and is related to its occurrence in the diet. As noted earlier, 

 the pigment originally designated as egg-yolk "lutein" was later found to be 

 a mixture of lutein and zeaxanthin. Although none of the carotenol is 

 present in cow or horse fat, it has been reported in chicken fat, as well as in 

 human fat.^^'^^^'^'^ Zechmeister and Tuzson^^^ were able to isolate 0.57 mg. 

 from one kilogram of the latter fat. In another study, these investigators^*^ 

 reported lipochromes in fats obtained from a variety of patients. The 

 highest value for lutein was found in abdominal fat obtained from a woman 

 suffering from jaundice. Considerable quantities of this carotenol were 

 also found in the livers of normal men^^^ and of patients who had died from 

 a variety of diseases.-*^ Lutein has been shown to be a component of 

 human skin, especially after the consumption of large quantities of winter 

 squash {Cucurhita maxima) over a prolonged period.'"* 



Despite the absence of lutein from cow depot fat, it is a constant com- 

 ponent of cow milk and of butter.*^* The highest values were found in 

 November butter, in which 0.7 mg. were present per 100 grams of water- 

 free butter fat. However, the amount dropped to low values later in the 

 winter; increased quantities were immediately evident as soon as the cow 

 again had green fodder. As might be expected, lutein is also found in the 

 serum of cattle. -^^ 



In the case of birds, lutein has been observed not only in the egg-yolk-®'' 

 and fat of hens,*'* but also in the feathers of the wild Madeira canary 

 (Serinus canarius) and of the yellow hammer {Emberizia citrinella) .^^^ It 

 is not particularly surprising to find it in skin appendages of birds, such as 

 feathers, in view of its deposition in human skin. Lutein has been isolated 

 from the green water frog {Rana esculenta) .^^^ The pigment is found in 

 many lower forms, such as the silkworm {Bomhyx mori)-^ and the red-brown 



'o' O. C. Magistad, Plant Physiol, 10, 187-191 (1935). 



30S H. Willstaedt, Svensk Kern. Tid., 48, 212-213 (1936); Chem. Absi., 31, 1900(1937). 



509 G. MacKinney, Plant Physiol., 12, 216-218 (1937). 



3'» J. C. Drummond, E. Singer, and R. .J. Mac- Walter, Biochem. J., 29, 456-471 (1935). 



'" H. H. Strain, Leaf Xanthophylls, Carnegie Institution of Washington Publication 

 No. 490, Washington, 1938. 



31^ B. Sullivan and C. H. Bailey, ./. Am. Chem. Soc, 58, 390-393 (1936). 



318 L. Zechmeister and P. Tuzson, Z. physiol. Chem., 225, 189-195 (1934). 



3" A. E. Gillam, I. M. Heilbron, R. .\. Morton, G. Bishop, and J. C. Drummond, 

 Biochem. J., 27, 878-888 (1933). 



316 H. Brockmann and O. Volker, Z. physiol. Chem., 224, 193-215 (1934). 



316 L. Zechmeister and P. Tuzson, Z. physiol. Chem., 238, 197-203 (1936). 



