Biological properties of sodium alkyl methyl ester sulfonate/alkyltrimethylammonium bromide surfactant mixtures

► Biological properties of CmMES/CnTAB mixtures were studied and compared. ► Equimolar mixtures showed optimal inhibitive power against S. aureus and E. coli. ► Cationic portion of the mixtures play dominant role in the inhibitive power. ► Mixtures with longer hydrocarbon chain length have little or no inhibitive power.