ii. chemistry 153 



2. Ergosterol 



Tanret^* discovered ergosterol in ergot, and Gerard^^ noted its occurrence 

 generally in the fungi. Heiduschka and Lindner'"" compared the ergosterol 

 content of ten fungi, including yeasts, finding from 0.29 to 1.17 % of ergos- 

 terol in the dry substance. The ergosterol content of twenty-nine species 

 and strains of yeast, grown under similar conditions, was determined spec- 

 trographically by Bills et al}^^ and found to vary from a trace to as high as 

 2.0% of the dry material. The ergosterol of commerce is obtained from 

 baker's yeast, i.e., strains of Saccharomyces cerevisiae grown in aerated wort. 

 Part of the supply was formerly obtained from Aspergillus niger,^^^ but this 

 source has been abandoned in favor of yeast. Savard and Grant'°^ cited 

 previous studies on the occurrence of ergosterol in several species of Penicil- 

 lium and isolated some ergosterol from the mycelium of P. notatum grown 

 in submerged culture. Although available in quantity from the antibiotics 

 industry, Penicillium has not become a commercial source of ergosterol, 

 because the yield is comparatively low. 



Windaus and Stange^*- ^^ isolated ergosterol from the sterol of hens' eggs. 

 Its presence there, in association with cholesterol, was surprising but ex- 

 plainable on the basis that it had been transferred from the feed of the 

 hens (cf. grass, grains, and earthworms, below). It is known'"'* that hens, 

 unlike mice, rats, rabbits, or dogs, absorb small amounts of fed ergosterol. 

 The finding of ergosterol in eggs does not preclude the possibility that other 

 provitamins D were also present but less readily isolated by the chromato- 

 graphic technique which was employed. 



Bock and Wetter'"^ studied the sterols of the vineyard snail, Helix 

 pomatia, the red road snail, or slug, Arion empiricorum, and the common 

 earthworm, Lumbricus terresiris. In these the major sterols were cholesterol 

 and some phytosterol-like substances, but the only provitamin isolated 

 from the mixtures was ergosterol. The coexistence of other provitamins was 

 not precluded, and almost certainly others were present, for Boer ei al}°^- '"^ 



38 C. Tanret, Ann. chim. et phys. Ser. 5, 17, 493 (1879); Compt. rend. 108, 98 (1889); 



Ann. chim. et phys. Ser. 6, 20, 289 (1890); Ser. 8, 15, 313 (1908). 

 89 E. Gdrard, Compt. rend. 114, 1544 (1892); 121, 723 (1895); 126, 909 (1898); J. pharm. 



chim. Ser. 6, 1, 601 (1895). 

 i"" A. Heiduschka and H. Lindner, Hoppe-Seyler's Z. physiol. Chem. 181, 15 (1929). 



101 C. E. Bills, O. N. Massengale, and P. S. Prickett, /. Biol. Chem. 87, 259 (1930). 



102 A. Zimmerli, U. S. Pat. 1,893,317 (1933). 



103 K. Savard and G. A. Grant, Science 104, 459 (1946). 



10* R. Schonheimer and H. Dam, Hoppe-Seyler's Z. physiol. Chem. 211, 241 (1932); 



W. Menschick and I. H. Page, ibid. 211, 246 (1932). 

 106 F. Bock and F. Wetter, Hoppe-Seyler's Z. physiol. Chem. 256, 33 (1938). 

 106 A. G. Boer, J. van Niekerk, E. H. Reerink, and A. van Wijk, U. S. Pat. 2,163,659 



(1939). 

 '07 A. G. Boer, J. van Niekerk, E. H. Reerink, and A. van Wijk, U. S. Pat. 2,266,674 



(1941). 



