The Enzymes o/B. coli communis. 



149 



Table V. — Products of the Aerobic and Anaerobic Fermentation of Glucose 

 by B. coli cornvmnis. Calculation of the elementary composition of the 

 products to illustrate the gain of oxygen, especially marked in anaerobic 

 fermentations. 



Products. 



Anaerobic. 



C. 



H. 



0. 



C. 



H. 



0. 



Total 



0-189 

 0-120 

 0-207 

 0-202 



-021 



0-020 

 -026 

 0-050 



-503 

 0-319 

 0-275 

 0-237 



0-208 

 -127 

 -206 

 0-237 



0-018 



-021 

 0-026 

 0-059 



0-553 

 -337 

 0-274 

 0-277 



0-718 



0-117 



1 -222 



0-778 



0-124 



1 -441 



Calculated for glucose 



Calculated on basis of the 

 carbon 



0-822 

 0-718 



0-137 

 0-120 



1 -095 

 0-056 



-890 

 0-778 



0-148 

 -130 



1 -185 

 1-037 



Products. 



Aerobic. 



C. 



H. 



0. 



C. 



H. 



0. 



Formic acid 



Alcobol 



Total 



0-080 

 0-082 

 -334 . 

 0-245 



0-014 



-014 

 -042 

 0-061 



-215 

 0-220 

 0-445 

 -163 



0-161 

 0-065 

 0-297 

 0-238 



0-008 



-Oil 



-037 

 0-059 



-426 

 -173 

 0-395 

 0-158 



0-741 



0-131 



1 -043 



0-761 



0-115 



1 -152 



Calculated for glucose 



Calculated on basis of the 

 carbon 



0-766 

 -741 



0-127 

 -124 



1 -022 



0-988 



0-811 

 -761 



-135 

 -127 



1 -080 

 1 -013 



Under anaerobic conditions greater variations occur in the proportion of 

 alcohol to acetic acid than under aerobic conditions, and it would appear 

 that one of the effects of the introduction of oxygen during the fermentation 

 is to inhibit the mechanism of auto-reduction, which is responsible for the 

 variations in alcohol when such occur. 



Contrary to expectation, the' products of aerobic fermentation contain 

 not more, but less, oxygen than the corresponding products of anaerobic 

 fermentation of glucose ; but there is a gain of oxygen in both cases upon the 

 original glucose. If, as seems likely, this extra oxygen comes from the water, 



VOL. xcii. — B. N 



