ORGANIZED AND UNORGANIZED FERMENTS. 31 



the fermenting body to absorb oxygen. Among these are, laccase, 

 an enzyme concerned in the formation of lacquer varnish from sap; 

 tyrosinase, producing colors in fungi; and oenoxydase, an enzyme 

 that causes certain diseases in wine. This list could be largely in- 

 creased by adding other less important enzymes. 



The simple enumeration of these lists is sufficient to emphasize 

 their variety, and only a brief examination is needed to show their 

 intimate relation to farm processes. Nearly all of those enumerated 

 have a more or less important relation to farm life, and not a few 

 farm products are quite dependent upon them, for example: vinegar- 

 making, due to the action of both yeasts and bacteria, and cheese 

 making, due to the enzyme, rennet, and likewise to bacteria. 

 When to this list we add the many serious animal and plant diseases 

 caused by germ life, with which the farmer is waging constant war- 

 fare, it becomes evident that agriculture and bacteriology must 

 hereafter be closely combined. 



Recognizing the great variety of these allied phenomena, it 

 becomes a little uncertain to what the term fermentation should be 

 applied. It originally referred to the alcoholic fermentation, but 

 later it was applied to the changes due to enzymes, and enzymes as 

 well as yeasts were said to be ferments. Frequently it has been 

 applied to any type of sugar fermentation brought about by yeasts 

 or bacteria, by which gas is produced; and when bacteriologists 

 use the term they usually refer simply to this change in sugars. 

 A term with so varied a meaning is of little value, and to-day there 

 is a tendency to give up its use, except in a popular sense to cover 

 such a general list of phenomena. 



IS THERE ANY DISTINCTION BETWEEN ORGAN- 

 IZED AND UNORGANIZED FERMENTS? 



The confusion is rendered still greater by the discovery of a series 

 of facts that lead to the breaking down of the distinction between 

 the organized ferments and the enzymes. It will be noticed that 

 these enzymes all come from living organisms, being secreted by 

 them; pepsin is secreted by the gastric glands, diastase by cells of 



