Secondary substrate utilization of methylene chloride by an isolated strain of Pseudomonas sp

Abstract

Secondary substrate utilization of methylene chloride was analyzed by using Pseudomonas sp. strain LP. Both batch and continuously fed reactors demonstrated that this strain was capable of simultaneously consuming 2 substrates at different concentrations: the primary substrate at the higher concentration (mg/l) and the secondary substrate at the lower concentration (.mu.g/l). The rate of methylene chloride utilization at trace concentrations was greater in the presence of the primary substrate, acetate, than without it. When the substrate roles were changed, the acetate secondary substrate utilization rate was less when methylene chloride was present. Thus, substrate interactions are important in the kinetics of secondary substrate utilization. Pseudomonas sp. strain LP showed a preference toward degrading methylene chloride over acetate, whether it was the primary or secondary substrate, providing it was below an inhibitory concentration of .apprx. 10 mg/l.