The anaerobic decomposition of benzoic acid during methane fermentation. IV. Dearomatization of the ring and volatile fatty acids formed on ring rupture.
A possible pathway for the anaerobic utilization of benzoic acid by a methanogenic consortium is suggested. Cyclohexane carboxylic acid and 1-cyclohexene-1-carboxylic acid have been identified as intermediates before ring rupture. Suprisingly, 3-cyclohexene-1-carboxylic acid interferes with utilization of other cyclic acids. In addition, isobutyric acid or short chain acids containing carbon-carbon double bonds could not be used without induction periods of a  week or longer. A number of volatile fatty acids (heptanoic, valeric, butyric, propanoic, and acetic) have been identified and are suggested intermediates.
D000693:Anaerobiosis; D001565:Benzoates / Q000378:metabolism*; D001673:Biodegradation, Environmental; D055598:Chemical Phenomena; D002621:Chemistry; D003509:Cyclohexanecarboxylic Acids / Q000378:metabolism; D019605:Euryarchaeota / Q000378:metabolism*; D005232:Fatty Acids, Volatile / Q000096:biosynthesis*; D005285:Fermentation; D008697:Methane / Q000096:biosynthesis*
D001565:Benzoates; D003509:Cyclohexanecarboxylic Acids; D005232:Fatty Acids, Volatile; D008697:Methane