Mechanism of Action of Phenolic Disinfectants VI: Effects on Glucose and Succinate Metabolism of Escherichia Coli

Abstract

A representative group of phenols was examined as to effects on aerobic and anaerobic utilization of glucose and aerobic utilization of sodium succinate. At low concentrations, p -chlorophenol, 2,4-dichlorophenol, p -chloro- o -cresol, and 2,4-dinitrophenol stimulated oxygen uptake with glucose as the substrate; phenol and p -chloro- m -xylenol were inhibitory, and p - tert -amylphenol had no measurable effect. At the higher concentrations used, all compounds except 2,4-dinitrophenol were inhibitory. Anaerobic metabolism of glucose was inhibited by concentrations of the compounds tested similar to those inhibiting glucose oxidation. Oxidation of sodium succinate was stimulated by low concentrations of p -chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, p -chloro- o -cresol, dichloro- m -xylenol, and p - tert -amylphenol. All compounds were inhibitory at higher concentrations. In general, sodium succinate oxidation was the most sensitive to phenolics, and glucose oxidation the least sensitive. There was some correlation between phenol coefficients and inhibition of glucose and succinate metabolism. It is hypothesized that the lethal action of phenolic disinfectants is due to damage of permeability mechanisms, the repair of which is prevented by concomitant inhibition of energy-yielding metabolic reactions.