DEGRADATION OF 2-CHLOROETHANOL BY FREE AND IMMOBILIZED PSEUDOMONAS-PUTIDA US-2

The degradation of 2-chloroethanol by Pseudomonas putida US 2 was inve stigated in shaking flasks, air-bubble columns and packed-bed fermente rs by free cells, calcium-alginate-entrapped cells and on cells on gra nular clay adsorbed. Entrapped cells tolerated increasing concentratio ns of 2-chloroethanol better than free cells. Their maximum degradativ e activity could be observed at 34 degrees C and pH 7.0. The degradati on of 2-chloroethanol leads to a decrease of pH and to a stagnation of mineralization, particularly with free or entrapped cells. Following the stabilization of pH, supplementation with succinate resulted in a complete degradation of higher 2-chloroethanol concentrations. Less 2- chloroethanol was degraded in air-bubble columns and larger amounts in packed-bed fermenters. 2-Chloroethanol was mineralized faster by free or entrapped P. putida US 2 than by adsorbed cells, which, on the oth er hand, were able to remove higher concentrations of the compound. Th e results with P. putida US 2 are a good indication that this microorg anism could be used in waste-water treatment and soil-decontamination systems.