As observed in earlier trials with bacterial cells, destructive activity of a quaternary ammonium compound against S. cremoris phage was increased by addition of chelating agents to the virucide. Concentrations of 50 to 100 ppm ethylenediamine tetraacetate and tetrasodium pyrophosphate sharply increased virucidal activity of 25 ppm quaternary, an effect observed earlier with chelating agents and quaternaries against certain bacterial species. Results suggest desirability of incorporation of chelating agents in quaternaries for sanitization not only for bacterial but also for bacteriophage destruction. The results also provide new information that may lead to a better understanding of mechanism of action of quaternaries against microorganisms.
1Technical Paper No. 1334 Oregon Agricultural Experiment Station. Contribution of the Department of Bacteriology.
2Present address: Lucky Lager Brewing Co., Research Department, San Francisco, California.