MAMMALIAN CAROTENOIDS 



A resolution of these differences may be arrived at by following up 

 Vavich and Kemmerer's ' ^ ' various experiments on chicks^ ^® 

 They found a differential effect ; the amount of vitamin A laid down in 

 the liver of vitamin A-deficient chicks (about 14 days old) fed 65 [xg./day 

 of [3-carotene was not affected by daily supplements of 300-600 [xg, of 

 xanthophylls. When the [3-carotene supplement was raised to 130 

 (Xg./day, then the xanthophylls had a marked deleterious effect. This 

 persisted even when the ^-carotenes was administered in three doses 

 at three hourly intervals. In a recent large-scale biological assay, 

 Callison, Hallaan, Martin, and Orent-Keiles ^ ^ 9 found that in rats 

 lutein had no demonstrable effect on the utilization of ^-carotene for 

 growth. 



In the experiments in which lutein was found to impair carotene 

 absorption, it was found that vitamin A absorption was equally affected. 

 This observation rules out the possibility of xanthophylls inhibiting 

 carotene utilization by competing with it for the hypothetical intestinal 

 enzyme carotenase. ^ ^ * 



REFERENCES 



1. Goodwin, T. W., and Gregory, R. A. (1948), Biochan. J., 43, 505. 



2. Glover, J., Goodwin, T. W., and Morton, R. A. (1947, 1948), Biochem. Jf., 41, xlv ; 



43, 512. 



3. Thompson, S. Y., Ganguly, J., and Kon, S. K. (1947), British y. Nut., 1, v. 



4. Mattson, F. H., Mehl, J. \y., and Deuel, H. J., jun., (1947), Arch. Biochem., 15, 65. 



5. Wiese, C. W., Mehl, J. W., and Deuel, H. J., jun. (1947), Arch. Biochem., 15, 75. 



6. Karrer, p., and Krause-Voith, E. (1948), Helv. Chim. Acta, 31, 802. 



7. Palmer, L. S., and Eckles, C. H. (1914), X hiol. Chem., 17, 191, 211, 223, 237, 245. 



8. Thudichum, J. L. (1869), Proc. Rov. Soc, 17, 253. 



9. Palmer, L. S. (1922), Carotinoids and Related Pigments. N. York. Reinhold. 



10. Berg, H. van den, Muller, P., and Broekme\^r, J. (1920), Biochem. Z., 108, 1279. 



11. Dzialoszynski, L. M., Mystkowski, T. A., and Stewart, C. P. (1945), Biochem. J., 



39, 63. 



12. Chalmers, T. A., Goodwin, T. W., and Morton, R. A. (1946), Nature, 155, 513. 



13. Goldblith, S. a., and Proctor, B. E. (1949), Nucleonics, 5, 50 ; 155, 513. 



14. Sullman, H., and VisCHER, A. (1934), Biochem. Z., 274, 16. ' 



15. Pratt, J. G. D., and Stern, M. I. (1949), Brit. J. Nut., 3, vii. 



16. Hess, A. F., and Meyers, V. C. (1919), y. Amer. Med. Assn., 73, 1743. 



17. Veen, A. G. van, and Lanzing, J. C. (1937), Proc. Soc. Amsterdam Acad., 10. 779. 



18. Krebs, H. A., and HUME, E. M. M. (1949), Med. Res. Council Sp. Rep. Series, No. 264. 



19. Zechmeister, L. (1934), Bull. Soc. Chim. Biol., 16, 993. 



20. Zechmeister, L., and Tuzson, P. (1935), Hoppe-Seyl. Z., 231, 259. 



21. Thompson, J. G. (1934), Z. fur. Exp. Mediz., 92, 692. 



22. Eekelen, M. van, and Haas, J. H. de (1934), Geneesk. tids. Nederland Ind., 74, 1201. 



23. WiLLSTAEDT, H., and W^ITH, T. K. (1938), Hoppe-Seyl. Z., 253, 40, 



24. Thompson, S. Y., Kon, S. K., and Mawson, E. H. (1942), Biochem. y., 36, xvii. 



25. Lesher, M., Brody, J. K., Williams, H. H., and Macy, I. G. (1945), Amer. y. Dis. 



Child, 10, 182. 



26. Truka-Tuzon, J. (1939), Z. Geburst u. Gynakol., 120, 86. 



27. Kon, S. K., and Mawson, E. H. (1950), Med. Res. Coun. Sp. Rep. Series, No. 269. 



28. With, T. K., and Friderichsen, C. (1939), Ugesksift Laeger, 101, 915. 



29. Friderichsen, C, and With, T. K. (1939), Ahn. Paediat., 153, 113. 



30. Willstaedt, H., and With, T. K. (1938), Nord. Med. Tidsk., 15, 648. 



31. Truika, J. (1940), Mag. orv. Arch., 41, 145. 



32. Chanda, R., Owen, E. C, and Cramond, B. (1951), Brit. y. Nutrit., (in the press). 



33. Zechmeister, L., and Tuzson, L. (1935), Hoppe-Seyl. Z., 231, 259. 



34. Daniel, E., and B6res, T. (1936), Hoppe-Seyl. Z., 238, 160. 



35. Findlay, G. M. (1920), y. Path. Bact., 23, 482. 



36. Maas, F. (1889), Ark. Mikr. Anat., 34, 452. 



37. Kuhn, R., and Brockmann, H. (1932), Hoppe-Seyl. Z., 206, 41. 



38. DOLLEY, D. H., and Guthrie, F. V. (1921), y. Med. Res., 42, 289. 



39. Willstaedt, H., and Lindquist, T. (1936), Hoppe-Seyl. Z., 240, 10. 



253 



