Abstract: Methods and compositions are disclosed for the microbial degradation of polychlorinated biphenyl compounds (PCBs) at a concentration of 100-200 mg/kg soil in contaminated environments, using natural, non-toxic, environmentally-acceptable compounds for application to such environments, such that PCB-contaminated environments are bioremediated by inducing a metabolic pathway in PCB-degrading microbes. Inoculated or indigenous PCB-degrading microbes, such as Arthrobacter strain B1B are induced to decontaminate the PCBs. Also disclosed are a plant and chemical screening assays for identifying plants that produce metabolites which promote PCB cometabolism. Further disclosed is a method for bioremediating PCB-contaminated environments in a commercially practical manner using l-carvone, a nontoxic and inexpensive chemical component of spearmint, for the in situ cleanup of PCB-contaminated soils, to induce Arthrobacter strain B1B to cometabolize and to substantially degrade PCBs.

Abstract: A recombinant microorganism strain having a desired metabolic property is produced by a process which utilizes a multiple chemostat system.

Abstract: Environments contaminated with toxic halogenated organic compounds are decontaminated at an accelerated rate by addition of (1) microorganisms which are non-indigenous to the environment and which metabolize the contaminant at a greater rate than microorganisms indigenous to the environment and (2) a non-toxic analog of the halogenated organic compound.