ISOLATION 



2. S. Lepkovsky and T. H. Jukes, ibid., 1936, 114, 109. 



3. C. E. Edgar, T. F. Macrae and F. Vivanco, Biochem. J., 1937, 31, 



879 ; C. E. Edgar and T. F. Macrae, ibid., 893. 



4. T. F. Macrae, A. R. Todd, B. Lythgoe, C. E. Work, H. G. Hind 



and M. M. El Sadr, ibid., 1939, 33, 1681. 



5. D. W. Woolley, H. A. Waisman, O. Mickelsen and C. A. Elvehjem, 



/. Biol. Chem., 1938, 125, 715. 



6. G. H. Hitchings and Y. SubbaRow, /. Nutrition, 1939, 18, 265. 



7. D. W. Woolley, H. A. Waisman and C. A. Elvehjem, /. Amer. 



Chem. Soc, 1939, 61, 977. 



8. R. J. Williams, ibid., 1933, 55, 2912. 



9. R. J. Williams, ibid., 1938, 60, 2719. 



10. T. H. Jukes, ibid., 1939, 61, 975. 



11. H. H. Weinstock, H. K. Mitchell, E. F. Pratt and R. J. Williams, 



ibid., 142 1. 



12. Y. SubbaRow and G. H. Hitchings, ibid., 1615. 



13. B. Lythgoe, T. F. Macrae, R. H. Stanley, A. R. Work and C. E. 



Work, Biochem. J., 1940, 34, 1335. 



14. S. Black, D, V. Frost and C. A. Elvehjem, /. Biol. Chem., 1940, 



132, 65. 

 15- J- J- Oleson and S. Black, ibid., 1940, 133, Ixxiii. 



16. D. V. Frost and C. A. Elvehjem, ibid., 1937, 119» xxxiv. 



17. D. W. Woolley, Proc. Soc. Exp. Biol. Med., 1940, 43, 352. 



18. H. Kringstad and G. Lunde, Z. physiol. Chem., 1939, 261, no. 



19. Y. SubbaRow and L. Rane, /. Amer. Chem. Soc, 1939, 61, 1616. 



20. G. H. Hitchings and D. W. Woolley, Science, 1939, 90, 41. 



21. R. J. Williams and R. T. Major, ibid., 1940, 91, 246. 



2. ISOLATION OF PANTOTHENIC ACID 



The method used by R. J. Williams et al.^ in the isolation of panto- 

 thenic acid from liver was as follows : the liver was allowed to autolyse 

 and then heated to coagulate proteins and filtered. Alternatively, 

 the minced liver was extracted with alcohol. In either instance, the 

 aqueous extract was shaken with fuller's earth to remove readily ad- 

 sorbed impurities and then with norit at pH 3-6 to adsorb pantothenic 

 acid. The adsorbate was eluted with dilute ammonia or with pyri- 

 dine-methanol. The eluate was neutralised with oxalic acid, and 

 brucine was added to form the brucine salts of pantothenic acid and 

 other acids. These were extracted with chloroform and fractionated 

 by partitioning between chloroform and water. The purified brucine 

 salt was decomposed by lime and the brucine removed by filtration 

 and extraction with chloroform. The calcium pantothenate was 

 purified by precipitation with alcohol, removal of impurities by pre- 

 cipitation with mercuric chloride, and fractional precipitation with 



351 



