Biodegradation of short and medium chain polychlorinated alkanes

摘要

Polychlorinated alkanes (PCAs) have due to their chemical stability worldwide applications, however, they are also persistent, bioaccumulative and toxic, and their environmental fate is of public concern. In order to estimate biodegradation potential of polychlorinated alkanes, two inputs are required: chemical characterization of PCA mixtures and definition of dehalogenase enzyme activity on PCAs. To address the first input, the free radical chlorination process was modelled using a Monte Carlo simulation. Even though the reaction probabilities were based on available literature data, the model showed to capture gross characteristics of PCA industrial mixture. To define dehalogenase enzyme activity, the biodegradation of chlorinated alkanes by oxygenolytic dehalogenase of Pseudomonas sp. 273 was studied. We examined the effect of carbon chain length, intramolecular chlorine distribution and overall chlorine content using commercially available compounds and chloroalkanes synthesized in our laboratory. The outcome is a definition of the chemical structures that both support and limit dehalogenation. This data will contribute to a better understanding of the environmental fate of PC As.