398 THE LIVER. 



Glycocholic acid crystallizes in fine, colorless needles or prisms. It 

 is soluble with difficulty in water (in about 300 parts cold and 120 parts 

 boiling water), and is easily precipitated from its alkali-salt solution 

 by the addition of dilute mineral acids. According to BONDI 1 glyco- 

 cholic acid is a rather strong acid, about as acid as lactic but much 

 stronger than acetic acid. This last-mentioned acid precipitates gly- 

 cocholic acid from the solution of its alkali salts in water. It is readily 

 soluble in strong alcohol, but with great difficulty in ether. The solu- 

 tions have a bitter but at the same time sweetish taste. The acid melts 

 between 132-152, depending upon the method of preparation. EMiCH 2 

 found the melting-point 132-134 for the acid crystallized out of water. 

 The salts of the alkalies and alkaline earths are soluble in alcohol and 

 water. 



The solution of the alkali salt in water can be salted out by NaCl, 

 but not by KC1. The salts of the heavy metals are mostly insoluble or 

 soluble with difficulty in water. The solution of the alkali salts in water 

 is precipitated by sugar of lead, cupric and ferric salts, and silver nitrate. 



Glycocholeic Acid is a second glycocholic acid, first isolated by WAHL- 

 GREN 3 from ox-bile, and has the formula C26H 43 NO5 or C27H 45 NO5. 

 This acid, which on hydrolytic cleavage yields glycocoll and choleic acid, 

 has also been detected in human bile and the bile of the musk-ox (HAM- 



MARSTEN 4 ) . 



Glycocholeic acid may, like glycocholic acid, crystallize in tufts of 

 fine needles, but is often obtained as short thick prisms. It is much more 

 insoluble in water, even on boiling, than glycocholic acid, and it melts 

 at 175-176 C. The alkali salts are soluble in water, have a pure bit- 

 ter taste, and are more readily precipitated by neutral salts (NaCl) than 

 the glycocholates. The solution of the alkali salts is not only precipitated 

 by the salts of the heavy metals, but also by the salts of barium, cal- 

 cium and magnesium. 



The principle of the preparation of the pure glycocholic acids consists 

 in treating a 2-3 per-cent solution of bile free from mucus, when rich in 

 glycocholic acid (so-called HUFNER'S bile 5 ), with ether, and then with 

 2-per cent hydrochloric acid. If the bile is not directly precipitable 

 with hydrochloric acid (bile relatively poor in glycocholic acid) then 

 precipitate the chief mass of the glycocholic acid with ferric chloride, 

 or better with lead acetate, decompose the precipitate with soda and treat 

 the 2-per cent solution as above stated with ether and hydrochloric acid. 



1 Zeitschr. f . physiol. Chem., 53. 



2 Monatsh. f. Chem., 3. 



8 Zeitschr. f . physiol. Chem., 36. 



4 Ibid., 43. 



5 Hiifner, Journ. f. prakt. Chem. (N. F.), 10, 19, and 25. 



