Antibacterial activity of surfactants against Escherichia coli cells is influenced by carbon source and anaerobiosis.

In order to clarify the involvement of an energy-yielding system in the antibacterial action of surfactants, the effects of carbon source and anaerobiosis during the growth period on the surfactant sensitivity of Escherichia coli cells were investigated. Cetyltrimethylammonium bromide (CTAB) and N-dodecyl-N,N-dimethylglycine, at relatively low concentrations, caused a delay in growth of E. coli cells. Cells grown in M9 medium supplemented with glycerol, succinate or acetate as a carbon source were more sensitive to surfactants and had a higher respiratory activity than those grown with glucose. Cultivation under anaerobiosis made cells resistant to CTAB. Bacterial sensitivity to surfactants was affected by carbon source and anaerobiosis. The results obtained should be helpful in determining suitable conditions of treatment in the practical use of surfactants for bacterial decontamination.