FERMENTS AND FERMENTATION. 81 



The catalytic agents produced in living cells or tissues are 

 called ferments. They are usually divided into two groups, 

 the so-called organized and unorganized ferments. The first 

 term is applied to those ferments which are connected in some 

 way with the life of the cells in which they are produced, 

 and which cannot be extracted from these cells. The un- 

 organized ferments can, on the other hand, be extracted 

 from the cells in which they are formed, and are able to 

 produce their characteristic actions outside of the cells as 

 well. The unorganized ferments are also known as enzymes 

 (KUHNE). To the latter class belong all the digestive ferments, 

 amylase, maltase, acid- and alkali-proteinase, etc., which 

 it has been possible to extract from the tissues or secretions 

 of the alimentary tract, and which produce their characteristic 

 reactions in a test-tube as well as in the living intestinal 

 tract. To the class of organized ferments belong all those 

 whose presence we recognize only by their chemical be- 

 havior and whose actiyjitiejj_continue only as long as the 

 cell in which they were produced" Ts~lnt act. Many of "the 

 "vital" activities of tissues have to be attributed to_such 

 organized ferments. It is Useless to~enumerate the organized 

 f erments^be'Cause the liitoT unorganized ferments (enzymes) 

 is constantly growing at the expense of the organized, and we 

 may hope in time to speak of enzymes alone. To illustrate, 

 we need only cite BUCHNER'S successful extraction of zymase 

 from the yeast-cell, which is able to bring about the decom- 

 position of glucose into alcohol and carbon dioxide quite as 

 readily as the yeast-cell itself. The discovery of BUCHNER is 

 mentioned in this connection because it takes away one of 

 the pillars which for decades have been utilized to support 

 the idea of the essential difference between organized and un- 

 organized ferments. In the pages which follow the terms 

 ferment and enzyme are used synonymously. 



The number of known ferments is already very large, and 

 is being added to daily. It is unfortunate that a uniform 

 system of nomenclature has not yet been adopted by all the 



