SOLVENT POWER OF THE BILE 367 



the latter alone is stopped, it is important to call attention to 

 the point that the bile acts as an important activator not only 

 upon the lipase of the pancreatic secretion but also upon 

 that of the unmixed intestinal juice. 



Solvent Power of the Bile. Since, following what has 

 been said above, the generally acknowledged powerful effect 

 of the bile on fat digestion does not seem thoroughly ex- 

 plained by its infmenceupon fat cleavage, earnest efforts have 

 been made to discover other explanatory possibilities. One 

 suggestion has brought into prominence the solvent power 

 of the bile for the higher fatty acids, and lipoids of all sorts. 

 If, for example, an opaque, milky suspension of lecithin be 

 treated with a solution of the biliary salts, the fluid be- 

 comes clear at once, and in the ultramicroscopic field the 

 suspended particles may be watched disappearing from 

 sight. 45 The combination of salts of the biliary acids, 

 lecithin, cholesterine and mucin in the bile form with the 

 soaps a physical-chemical system in which (as we have 

 learned from the studies of Moore and Eockwood, Pfliiger 

 and Eossi 46 ) fatty acids are soluble to so great an extent 

 that, as a matter of fact, the largest amounts which could 

 possibly be regarded as within bound of physiological oc- 

 currence are converted to a water soluble form. This is the 

 more important, as soaps in the intestinal contents very 

 readily undergo hydrolytic dissociation from the influence 

 of carbonic acid, fatty acids being observable as a conse- 

 quence in free state even in the presence of notable amounts 

 of sodium carbonate. 47 Whether, in addition to this im- 

 portant point, the favoring influence (at one time looked 

 upon as important) of the alkali contained in the bile upon 

 emulsification of fat, and the reduction of the surface ten- 

 sion of the intestinal contents by the salts of the biliary 



45 L. Kalaboukoff and E. F. Terroine, C. R. Soc. de Biol., 66, 176, 1909. 



46 G. Rossi (G-. Fano's Lab., Florence), Arch, di FisioL, 4, 429, 1907, cited 

 in Centralbl. f. PhysioL, 21, 811, 1907. 



47 G. Rossi, 1. c. 



