Bioaugmentation of pentachlorophenol in soil and hydroponic systems

Sphingobium chlorophenolicum is well known as pentachlorophenol (PCP) degrader. The objective of this study was to evaluate the PCP degradation in soil and hydroponic systems using a bioaugmentation technique. Measurements of PCP concentrations were carried out using high-performance liquid chromatography (HPLC) analyses. The toxic effect of PCP on plants was studied through the monitoring of plant weight. An acute toxicity assay of PCP was performed using Escherichia coli HB101 pUCD607. The introduction of S. chlorophenolicum into soil with plants showed a faster degradation when compared to the non-inoculated soil. In the soil system, plants acted as a vector to the target compound, PCP. The monitoring of the plant growth showed a protective role of S. chlorophenolicum against the toxicity of PCP. In the hydroponic system S. chlorophenolicum showed the ability to degrade 16 mg l−1 after 7 days of experiments at both concentrations tested (20 and 30 mg l−1 PCP). The bioassay confirmed that initial toxicity was lowered while degradation progressed in both systems.