34 CHEMICAL TRANSFORMATIONS 



of being insoluble in water renders the attainment of such 

 concentrated solutions an impossibility in all attempts at 

 synthesis hitherto made, and for this reason no satisfactory 

 proof of syntheses of neutral fats by lipase have hitherto been 

 furnished. 



The theory of equilibrium in solution proves, however, that 

 given the possibility of obtaining more concentrated solutions of 

 the fatty acids, the synthesis of neutral fats by enzymes is quite 

 possible ; and in the conditions obtaining in the cell, where 

 the solvent is not water but the cell protoplasm, and where also 

 other solvents, such as the bile salts, may be present in con- 

 centrated solution, the synthesis of fats may well occur by such 

 means. 



The synthesis of neutral fat from soap and glycerine solutions 

 has been claimed by C. A. Ewald, and by Hamburger, by the 

 action of the isolated cells of the intestinal mucous membranes ; 

 but similar experiments by the writer of this article, in which both 

 the cells and cell-free extracts of the cells were used from the 

 intestinal mucosa, lymphatic glands, and the pancreas, demon- 

 strated that no trace of neutral fat was ever formed, the only 

 action observable being a setting free of fatty acids from the soaps 

 used. The observations of the authors quoted above, being 

 obtained by difference between total ethereal extract and free 

 fatty acid, were shown to be due to unaltered soaps dissolved out 

 by the ether. 



In regard to the synthesis of more complex carbohydrates 

 from the sugars by reversed action of enzymes, it may be stated 

 that Cremer has claimed to have observed a synthesis of glycogen 

 from sugar by the action of Buchner's Zymase, but the result has 

 not yet been confirmed. 



IV. The most general case of equilibrium in solution is that 

 where an' indefinite number of substances react together, and the 

 equation, as demonstrated on page 27, becomes 



Pa' -pb' pc' l rn 

 ' * *' &C ' r 



which may be written 



P . Pg . Pg . &c. = K . P . P 



