The After Effect of Irradiated Halogenophenol Solutions on the Viability of Escherichia coli

Part II. Effect of After Irradiation Treatments on the Bactericidsal Activity of Irradiated p-Bromophenol Solution

Abstract

Bactericidal activity of halogenophenol solution on E. coli was affected very much by post-irradiation treatments. The activity was significantly modified by heating at 80°C; it increased rapidly at an initial stage then decreased with increasing periods of heating until its complete disappearance. The addition of cysteine or sodium sulfite in the irradi-ated reagent solution prior to mixing with cells abolished the induced activity. The bactericidal factor is unstable at alkaline side, but is relatively stable at acidic side. The apparent induced activity depends on the cell concentration and the temperature at the period of contact with the irradiated reagent solution; no lethality was found at concen-trations above 108 cells per ml.