Effect of volatile fatty acids on Salmonella typhimurium

It has been established for many years that volatile fatty acids have an inhibitory or bactericidal effect on a number of bacterial species. D. J. Hentges (3) noted that shigellae were inhibited when grown in association with Klebsiella sp. He identified the compounds responsible for this inhibition as formic acid and acetic acid, products of the metabolism of Klebsiella. In a In order to define the conditions affecting the sensitivity of S. typhimurium to volatile fatty acids, the following experiments were performed. In all experiments the inoculum of S. typhimurium was prepared by diluting a 24-hr nutrient broth culture to provide an initial level of 5 X 103 to 5 x 104 cells per ml in the test solution. The test solutions consisted of a nutrient broth base to