524 VI. CAROTENOIDS AND RELATED COMPOUNDS 



Other workers/ --'^"^ likewise failed to detect any carotene in wheat flour, 

 although the presence of xanthophyll was demonstrated. 



It has long been known that jS-carotene is the chief polyene in carrots, 

 since this was the source from which it was originally isolated. However, 

 Strain^-^ proved that a-, 7-, and 5-carotene were also present in this vege- 

 table, as well as a carotenoid similar to flavoxanthin. /3-Carotene is known 

 to be a component of yeast and of other fungi, 125-127 ^^ ^ygjj ^s, of a saprophj^- 

 tic sporangiferous fungus {Piloholus kleinii).^^^ 



Although preformed vitamin A is more frequently found in the animal 

 tissues than are provitamins A, nevertheless there is a fairly wide distribu- 

 tion of carotenoids in the animal kingdom. jS-Carotene is frequently found 

 in the reproductive organs. Its presence has been noted in corpora 

 lutea,*^'^^^'^^" and in the corpus rubmm of the cow,^^^ in human placenta,^^^ 

 and in bull testes. ^^- It has also been found in the sex glands of the sea 

 urchin {Echinus esculentus) .^^^ It has been reported in human depot fat^'* 

 and blood serum,^^-^^^ ox blood serum, ^^^ and human and cow milk.^^-^^^-^^* 

 It would seem to be an important component of the adrenal glands of prac- 

 tically all mammals, where its presence has been noted by a number of 

 workers. ^*^~^'*^ It occurs in the fatty tissues of those animals which do not 

 convert it to vitamin A in the intestinal wall. Thus, it is not found in the 

 rat, chicken, pig, and goat, but it is present in the fat of dogs, cows, and 

 man.^*°'^^^~^'*^ An accumulation of /3-carotene likewise occurs in the livers 



1" M. Malmberg and H. v. Euler, Biochem. Z., 284, 238-243 (1936). 

 1" F. P. Bowden and T. Moore, Nature, 132, 204-205 (1933). 



124 H. H. Strain, J. Biol. Chem., 127, 191-201 (1939). 



125 E. Lederer, Les Carotenoides des Plantes, Paris, 1934. Cited by R. J. Williams, 

 Vitamins and Hormones, 1, 229-247 (1943). 



126 A. Scheunert and J. Reschke, Deut. med. Wochschr., 57, 349-351 (1931). 

 12' P. Karrer and J. Rutschmann, Helv. Chim. Acta., 29, 355-356 (1946). 



128 E. Banning, Planta, 26, 719-736 (1937). 



128 R. Kuhn and W. Schlientz, Helv. Chim. Acta, 17, 7-8 (1934). 



130 H. H. Escher, Z. phtjsiol. Chem., 83, 198-211 (1913). 



1" R. Kuhn and H. Brockmann, Z. physiol. Chem., 206, 41-64 (1932). 



"2 R. Netter, Bull. soc. chim. biol, U, 1555-1559 (1932). 



133 E. Lederer, Compt. rend., 201, 300-302 (1935). 



134 L. Zechmeister and P. Tuzson, Z. physiol. Chem., 231, 259-264 (1935). 



135 H. Willstaedt and T. Lindquist, Z. physiol. Chem., 24O, 10-18 (1936). 



i3« B. V. Euler, H. v. Euler, and H. Hellstrom, Biochem. Z., 203, 370-384 (1928) 



137 L. S. Palmer and C. H. Eckles, /. Biol. Chem., 17, 245-249 (1914). 



138 A. E. Gillam and M. S. El Ridi, Biochem. J., 31, 251-253 (1937). 



139 O. Bailly and R. Netter, Compt. rend., 193, 961-963 (1931). 



i« H. van den Bergh, P. Muller, and J. Broekmever, Biochem. Z., 108, 279-303 (1920). 

 1" C. L. Connor, J. Biol. Chem., 77, 619-626 (1928). 

 "2 C. L. Connor, Am. J. Path., 4, 293-308 (1928). 

 1" H. V. Euler and E. Virgin, Biochem. Z., 245, 252-264 (1932). 

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 i« O. Bailly, Cheyn. Zentr., 1935, I, 3806. Cited by P. Karrer and E. Jucker, Carotin- 

 oide, Birkhauser, Basle, 1948. 



i« L. S. Palmer and C. H. Eckles, J. Biol. Chem., 17, 211-221 (1914). 

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