RECENT WORK ON THE CHEMISTRY 

 OF CHOLESTERINE 



By CHARLES DOREE, M.A., B.Sc, and J. A. GARDNER, M.A. 



Cholesterine, or Cholesterol, is a white crystalline substance 

 which appears to be found in most of the tissues and fluids of 

 animals, and — in the isomeric form of phytosterine or vegetable 

 cholesterine — in the seeds and shoots of plants. The human 

 brain contains about 27 grammes, or 2\ per cent, of its weight 

 of cholesterine (Benecke), 1 and it is found in smaller quantities 

 in the spleen, in the blood (*i per cent.), in milk (04 per cent.), 

 and in bile ('2-*4 per cent.). It occurs also in certain tumours 

 and other pathological products, and particularly in gall- 

 stones, which, containing as they do 90-98 per cent, of 

 cholesterine, constitute the chief source of the substance for 

 scientific purposes. It is only necessary to dissolve the 

 powdered stones in benzene, allow the solution to deposit a 

 small quantity of pigment, filter, and nearly pure cholesterine 

 separates out. 



From the brain it is best obtained by the method of 

 Rosenheim. 2 The minced material is mixed with some sand 

 and three times its weight of plaster of Paris. This combines 

 with the water, and the whole mass sets hard in a few hours, 

 and may be broken up to a coarse powder very suitable for the 

 extraction, which is done with acetone. Lecithin and kephalin 

 being insoluble in cold acetone, the extract obtained, on evapora- 

 tion, yields nearly pure cholesterine. From other organs and 

 tissues it is usually obtained by extracting the dried substance 

 with ether. The separation of the fat is stated to be frequently 

 incomplete even after prolonged extraction, and in this con- 

 nection it may be mentioned that C. Dormeyer 3 has shown that 

 by submitting the material to artificial digestion a further yield 



1 Cf. also Miss M. C. Tebb, Joum. Physiology, 34, 107. 



2 Journ. Physiology, 34, 104. 



3 Pfliig. Archiv. 61, 341. 



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