Degradation of polychlorinated biphenyls by extracellular enzymes of Phanerochaete chrysosporium produced in a perforated plate bioreactor

The white rot fungus Phanerochaete chrysosporium was cultivated in a perfor ated plate bioreactor and the expression of activities of manganese-depende nt peroxidase (MnP) and lignin peroxidase (LiP) was measured. Peak activiti es of the two enzymes were reached close to day 11 and therefore the cultiv ation was terminated on that day. Extracellular proteins were concentrated and both peroxidases separated by isoelectric focusing. Degradation of tech nical PCB mixtures containing low and highly chlorinated congeners (Delor 1 03 and Delor 106 as equivalents of Aroclor 1242 and Aroclor 1260, respectiv ely) was performed using intact mycelium, crude extracellular liquid and en riched MnP and LiP. A decrease in PCB concentration caused by a 44-h treatm ent with mycelium (74% w/w for Delor 103 and 73% for Delor 106) or crude ex tracellular liquid (62% for Delor 103 and 58% for Delor 106) was observed. The degradation was not substrate-specific, because no significant differen ces between the respective degradation rates were observed with di-, tri-, tetra-, penta-, hexa-, hepta-, and octachlorinated congeners. In contrast, MnP and LiP isolated from the above-mentioned extracellular liquid did not catalyse any degradation.