Pentachlorophenol degradation using lignin peroxidase produced from the Phanerochaete chrysosporium immobilized in polyurethane foam.

Lignin peroxidase(LiP) production and its usage for biodegradation of pentachlorophenol(PCP) were studied. Experiments for lignin peroxidase production have been conducted by aerobic fermentation of P. chrysosporium in order to find the optimum conditions for a previously mentioned parameter, shear stress. It has been found that immobilization on polyurethane foam is a good means for overcoming the high shear sensitivity. Scanning Electron Microscopy(SEM) pictures showed that this strain was very well attached and growing on the polyurethane foams. The production of lignin peroxidase by free and immobilized cultures of P. chrysosporium was studied. Free pellets of this strain produced a little of lignin peroxidase(about 30 unit/liter), but the lignin peroxidase production was increased by immobilizing the cells on polyurethane foam (about 250 unit/L). Cell-free culture fluids harvested from nitrogen limited cultures were used to degrade pentachlorophenol (PCP). The culture fluid containing lignin peroxidase underwent the pentachlorophenol degradation and produced intermediates. Biodegradation of PCP(30ppm) by cell-free culture fluid was detected by HPLC analysis. Analysis of two reaction mixtures (PCP 30 ppm + Culture fluid 40 unit/L + [H2O2 0.5 mM] or not) during 6 hours showed disappearance of about 70 % pentachlorophenol(PCP). Unidentified intermediates as byproducts were detected by HPLC assay in the pentachlorophenol(PCP) treatment using cell-free culture fluids.