CHOLESTERINS. 449 



found a dihydrocholesterin in the contents in a part of the ileum which had been 

 disconnected from the other part of the intestine for 14 years. This had the 

 same optical rotation and the same melting-point, 142-143 C., as the dihydro- 

 cholesterin (j3-cholestanol) prepared by DIELS and ABDERHALDEN, WILLSTATTER 

 and MAYER. 



Hippokoprosterin is another cholesterin richer in hydrogen, which BONDZYNSKI 

 and HUMNICKI found in the feces of the horse. Its formula is CmH^O. According 

 to DOREE and GARDNER it is not an animal cleavage product, but a constituent 

 of the grass used as fodder. It melts at 78.5-79.5 C. 



Isocholesterin is a cholesterin, so called by SCHULZE, x with the formula 

 C 2 6H 44 0, which occurs in wool-fat, and is therefore found to a great extent in 

 so-called lanolin. It gives the LIEBERMANN-BURCHARD reaction, but does not 

 give SALKOWSKI'S reaction. It melts at 138-138.5 C. The specific rotation in 

 7 per cent ethereal solution is () D = 4-59.1. 



Spongosterin, C^EUO is the^name given by HENZE 2 to a cholesterin isolated by 

 him from a silicious sponge. It is very similar to cholesterin, but is not identical 

 with it or with phytocholesterins. It gives the LIEBERMANN-BURCHARD reaction as 

 well as SALKOWSKI'S reaction, but the last test is not quite so beautiful a red. 

 OBERMULLER'S reaction is negative. Melting-point 123-124. 



Bombicesterin is the name given by MENOZZI and MORESCHI 3 to a cholesterin 

 isolated by them from the chrysalis of the silkworm, which has a melting-point 

 of 148 and a specific rotation of () D = -34. 



The cholesterin occurring in the intestine is derived in part from the 

 food, in part from the bile and part, as shown from the contents of a 

 ligatured portion of the intestine (see Chapter VIII), from the epithelium 

 or the secretion of the intestinal mucosa. That a part of the cholesterin 

 of the intestine disappears has been shown by KUSUMOTO, although 

 it remains undecided whether this takes place by bacterial decomposi- 

 tion or by absorption. LEVITES 4 on the contrary, recovered the cho- 

 lesterin introduced into dogs almost quantitatively. The behavior of 

 cholesterin in metabolism is not well known; LIFSCHUTZ believes that he 

 has detected by his color-reaction the oxidation products of cholesterin 

 in the blood and in bone-fat. 



The cholesterins belong to the so-called lipoids, which have been 

 mentioned in previous chapters (I and VI), and are of the greatest 

 importance as constituents of the outer envelope of erythrocytes and 

 the cells in general. Cholesterin is also of great interest because it inhibits 

 or prevents the haemolysis produced by certain bodies, and therefore 

 acts as a certain protective power in the animal bod} r . This action of 

 the cholesterins in regard to inhibiting the hsemolytic action of saponin, 



1 Ber. d. deutsch. chem. Gesellsch., 6; Journal f. prakt. Chem. (N. F.), 25; and 

 Zeitschr. f. physiol. Chem., 14, 522. See also E. Schulze and J. Barbieri, Journal f. 

 prakt. Chem. (N. F.), 25, 159. In regard to the formula for isocholesterin, see 

 Darmstadter and Lifschiitz, Ber. d. deutsch. chem. Gesellsch., 31, and E. Schulze, 

 ibid., 1200. 



2 Zeitschr. f. physiol. Chem., 41 and 55. 



Cited from Chem. Centralbl., 1908, 1377 and 1910, 872. 

 4 Zeitschr. f. physiol. Chem., 57. 



