Electrochemical Sterilization of E. coli AB-1157 in Aqueous Suspension Containing NaCI

Abstract

Galvanostatic electrolysis of an aqueous suspension of E. coli (AB-1157) containing 0.45 wt%NaCl was studied. The surviving fraction of E. coli decreased upon electrolysis in the presence of NaCl. However the fraction did not change in the absence of NaCl or in the case of no electrolysis. The apparent energy required for 99% sterilization was constant irrespective of the current density, and increased in proportion to the reciprocal of NaCl concentration. The 99% sterilization energy in the electrolysis was less than that in the γ-radiolysis by a factor of about 100. The lethal damage of E. coli (AB-1157) was accelerated by dissolved oxygen, as observed in the aerated and oxygenated systems, but was not induced by preelectrolysis of an aqueous NaCl solution for 4 min at 1 mA followed by incubation of E. coli.