10 



BACTERIAL FERMENTATIONS 



They have all been shown, mainly by Buswell and his 

 collaborators, 15 - 16 to be converted more or less quantita- 

 tively into methane and carbon dioxide by crude cultures 



TABLE 1 



Compounds Known to Be Decomposed by Methane Bacteria 

 (Based on experiments with pure or purified cultures) 



derived from sewage sludge. Since these compounds are 

 not known to be attacked by other anaerobic bacteria under 

 the test conditions used, they are probably decomposed by 

 methane bacteria. 



TABLE 2 



Some Compounds Probably Decomposed by Methane Bacteria 



(Based on experiments with enrichment cultures) 



n-Caprylic acid 

 n-Capric acid 

 Isobutyric acid 

 Stearic acid 

 Oleic acid 



Benzoic acid 

 Phenylacetic acid 

 Hydrocinnamic acid 

 Cinnamic acid 



Oxalic acid 

 Succinic acid 

 Acetone 

 2,3-Butylene glycol 



In the older literature concerned with anaerobic decom- 

 position processes in nature it is often stated that many 

 other compounds such as sugars, cellulose, proteins, purines, 

 glycerol, lactate, and citrate are also suitable substrates for 



