Effect of anaesthetics and dichlorodifluoromethane on the viability of the cells of Escherichia coli and the activities of some of its enzymes.

Three anaesthetics (halothane, CF3CHClBr; Ethrane, F2 HCOF2CCHClF; cyclopropane) and one other halogenated, short-chain hydrocarbon (F-12, Cl2F2C) were tested under various conditions to determine their effects on the viability of cells of Escherichia coli and the activities of some of its enzymes. When any of the test chemicals were applied for 60 min at concentrations slightly in excess of saturation, the number of surviving cells decreased substantially, with halothane being the most biocidal of the four chemicals and F-12 the least. Three enzymes (malate dehydrogenase, MD; NADH dehydrogenase; glyceraldehyde-3-phosphate dehydrogenase, GPD) were tested for activity after treatment of E. coli with the test chemicals. In all instances, GPD was least resistant to inactivation and MD was most resistant. Halothane was most inhibitory followed in order by Ethrane, cyclopropane and F-12. Treatment of E. coli with halothane for 60 min at 23 degrees C and a concentration slightly in excess of saturation, resulted in nearly complete inhibition of all three enzymes.