SURVIVOR CURVES OF BACTERIA EXPOSED TO SURFACE-ACTIVE AGENTS

Publisher Website
Google Scholar
Abstract
These studies were conducted in order to investigate factors other than an aggregation phenomenon which might influence the death rate of organisms exposed to quaternary ammonium compounds, and thus, be responsible for the observed atypical survivor curve. Cultures of Micrococcus pyogenes var. aureus, Escherichia coli. Pseudomonas aeruginosa. and spores of Bacillus subtilis were used. The detergents selected were classified as: cationic[long dash]"Hyamine 1622," "Roccal," "Emulsept," "Tera-mine"; anionic[long dash]"Dreft," "Tide," "Santomerse 3," "Syntex A," "Oronite D-40";nonionic[long dash]"S.T. 37," "Triton 100," "Triton X30." The bacteria-detergent mixtures were incubated, and plated out at given time intervals. The result indicated that the atypical survivor curves of organism exposed* to surface active agents cannot be adequately explained on the basis of: presence or development of resistant variants, effect of age of cells, or the exhaustion of the active detergent. The authors postulated that the survivor curves were the result not only of direct chemical disinfection, but of certain physical effects, such as agglomeration, and thus do not provide a true index to the death rate.