Biochemistry of the Acetone and Butyl Alco- Hol Fermentation of Starch by Bacillus Granulobacter Pectinovorum

During the last 4 years a considerable amount of research, chiefly along industrial lines, has been performed in connection with the production of acetone together with various alcohols by the fermentation of carbohydrate media, using cultures of different bacteria. Some of this work has already been described in the literature (1, 2). Contributions have also been made to our knowledge of the biochemistry of these important processes. Northrop and his collaborators (3) have studied in detail the behavior of Bacillus acetoethylicum in standard media, and also the influence of certain factors, namely the reaction of the media, the size of the inoculation, the supply of air and nitrogen (peptone), and the temperature of the medium, on the growth of the organism and the yields of acetone and ethyl alcohol. They record that the principal acid produced during the fermentation is formic. At a conference held in London during the past year the position regarding the production of acetone with butyl alcohol by fermentation methods was discussed (4). More recently Fred and his collaborators (5) have shown that during the fermentation of xylose a mixture of acetic and lactic acids is produced, using cultures of bacteria isolated from manure, silage, etc. An effort has been made during this investigation to identify and study the role of the intermediate compounds formed during the fermentation of starch by Bacillus granulobacter pectinovorum.l