FIXATION OF ATMOSPHERIC NITROGEN 



565 



become more alkaline because of the utilization of the organic acids 

 present as sources of energy. 19 Some aerobic bacteria may produce ethyl 

 alchohol and acetic acid out of the sugar, in the process of nitrogen 

 fixation. 20 



a 5 





a/ 



Fig. 39. Rate of decomposition of glucose and fixation of nitrogen by Azoto- 

 bacter (after Hunter). 



The maximum formation of carbon dioxide by Azotobacter takes place 

 within the fourth to tenth day of growth. 21 Active C0 2 production 



19 Prazmowski, 1912 (p. 114); Omeliansky, W. L., and Ssewerowa, O. P. Die 

 Pigmentbildung in Kulturen des Azotobacter chroococcum. Centrbl. Bakt. II, 

 29: 643-650. 1911. 



20 Truffaut, G., and Bezssonoff, N. Une nouvelle bactcrie du sol, le Bacillus 

 truffauti, fixateur aerobie d'azote atmospherique. La Science du sol., 2: 3-16. 

 1923. 



"Stoklasa, 1908 (p. 562). 



