Inhibition of membrane bound ATPases of Escherichia coli and Listeria monocytogenes by plant oil aromatics

Lactobacillus sakei is highly resistant to cinnamaldehyde compared to E. coli and L. monocytogenes. To determine whether this resistance was related to the relative hydrophobicity of the cell surface and hence the ability of the cell to take up the aromatics, the percentage of the three organisms partitioning in dodecane was compared. No significant difference was found between the partitioning percentage of L. monocytogenes (17.2%) and L. sakei (13.8%), indicating that surface hydrophobicity does not explain the differing sensitivity to cinnamaldehyde of these two organism. The percent partitioning of E. coli was significantly greater than both other organisms (23.3%) and may explain the greater sensitivity of E. coli to all three aromatics.