Abstract
The volatile fatty acids produced by the representative strains of clostridia isolated from paddy field soil were surveyed. All the strains, except Cl. tertium, utilized only amino acids as the sole source of energy for growth. All of them produced acetic and butyric acids, and some of them produced propionic acid in addition. Iso-valeric and iso-butyric acids were also produced, except by Cl. tertium. These results suggest that all the strains, except Cl. tertium, may carry out the STICKLAND reaction. The cells of each strain harvested from the culture in the VL medium were subjected to examination whether or not they carried out the STICKLAND reaction in the presence of leucine or glycine. All the strains, except Cl. tertium, catalyzed the STICKLAND reaction and some strains also metabolized leucine and glycine even when they were supplied singly.