CHAPTER II. 



PRODUCTS OF BACTERIAL ENERGY. 



>C According to their chemical activities, bacteria are arbitrarily 

 divided into the following classes: 



^ Photogens Chromogens Zymogens 



Saprogens Aero gens Pathogens ^ 



^-Photogens are those bacteria of the sea, putrefying flesh, and 

 damp rotten wood, that produce a faint phosphorescence. ^ 



A Chromogens are bacteria that produce colors as they grow, 

 notable among which may be mentioned the Staphylococcus aureus, 

 that are golden in hue; B. pyocyaneus, of a greenish-blue; and 

 B. prodigiosus which appears a brilliant red. 7*-* 



_t Zymogens are the bacteria of fermentation, which is the chemical 

 transformation of carbohydrates by the action of bacteria, with the 

 evolution of CO 2 CO & H. Such bacteria are useful in the in- 

 dustries for the production of alcoholic beverages, wine, beer, etc. 

 Through the actions of these organisms grape sugar is converted 

 into alcohol, lactic acid, and acetic acid. yt. 



C 6 H 1 2 O 6 = 2 C 2 H 6 O+2 CO 2 



glucose 2 alcohol 2 carbonic acid 

 or 



C 6 H 12 0,= 2C 3 H 6 3 



2 lactic acid 

 or 



C 6 H 12 6 = 3 C 2 H,0 2 

 2 acetic acid 

 21 



