II. CHEMISTRY 9 



presented evidence for the hydrolysis of lecithin to GPC by rat intestine, 

 and Shapiro^^ has demonstrated the formation of GPC from lecithin, by 

 a cell-free extract of pancreas. 



Cyclic choline sulfate was isolated from Aspergillus sydowi by WooUey 

 and Peterson, ^^ who obtained it both from an autolyzate and from an 

 acetone extract of defatted mycelium. The yield was 0.26 % based on the 

 weight of the dry mycelium. The isolated cyclic sulfate was believed to be 

 identical with a synthetic product of the formula C5H13O4NS which had 

 been previously synthesized from choline chloride and sulfuric acid by 

 Schmidt and Wagner.^* Its use as a source of sulfur by Aspergillus oryzae 

 has been reported. ^^ 



As yet no methods exist for the accurate isolation and determination of 

 the different forms of choline in biological materials, particularly free 

 choline and combined water-soluble choline. Kahane and Levy^*^ defined 

 water-soluble choline as the total found in aqueous extracts of tissues after 

 suitable precipitation and filtration. Ferric hydroxide formed mthin the 

 mixture by addition of ferric sulfate and calcium carbonate was recom- 

 mended as the best precipitating agent. The choline of lecithin would not 

 be included in the total water-soluble choline. 



Several attempts have been made to devise procedures for the separation 

 of free choline from combined water-soluble choline as well as from other 

 water-soluble substances which may interfere with its isolation and quanti- 

 tative determination. Gebauer-Fuelnegg and Kendall" appHed electro- 

 dialysis to the separation of histidine from histamine or choline, and also 

 to the separation of an artificial mixture of protein or gelatin from histamine 

 or choline. This is reported to be a suitable method for the separation of 

 relatively strong, crystalloidal bases from mixtures mth amphoteric or 

 more weakly basic substances. 



HoroAvitz and Beadle^- used Permutit columns to separate choline from 

 non-basic interfering substances. They found that a Permutit column meas- 

 uring 110 X 0.6 mm., containing approximately 1 g. ^f Permutit, com- 

 pletely removes the choline from 5 ml. of a solution containing up to 0.5 

 mg. of choline per milliliter. Repeated tests showed that the absorbed 

 choline is quantitatively eluted with 10 ml. of 5 % sodium chloride. 



" E. Kahane and J. Ldvy, Helv. Chim. Acta 29, 1322 (1946). 



66 B. Shapiro, Nature 169, 29 (1952). 



" D. W. Woolley and W. H. Peterson, /. Biol. Chem. 122, 213 (1937). 



" E. Schmidt and W. Wagner, Ann. 337, 51 (1904). 



68 F. Egami and M. Itabashi, Igaku to Seibutsugaku 19, 292 (1951). 



60 E. Kahane and J. L6vy, Bull. sac. chim. hiol. 21, 223 (1939). 



6' E. Gebauer-Fuelnegg and A. I. Kendall, Bcr. 64B, 1067 (1931). 



62 N. H. Horowitz and G. W. Beadle, J. Biol. Chem. 150, 325 (1943). 



