Degradation of polychlorinated biphenyl mixtures by the lignin-degrading fungus Phanerochaete chrysosporium

Degradation of lower-chlorinated and higher-chlorinated PCB congeners (Delor 103 and Delor 105 as equivalents of Aroclor 1242 and Aroclor 1254, respectively) by the white-rot fungus Phanerochaete chrysosporium was investigated in N-limited and non-limited media. No degradation of either Delor 103 or Delor 105 was found in a N-limited medium 9 d after their addition whereas in the non-limited medium during the same period their levels dropped by 55 and 58 %, respectively. The degradation was non-specific and no significant differences in the degradation of di-, tri-, tetra-, penta-, hexa-, and hepta-congeners were found. No activity of Mn-dependent peroxidase (MnP) or lignin peroxidase (LIP) was detectable in the non-limited medium. We assume that the degradation of PCBs by P. chrysosporium is relatively non-specific, takes place under non-limited conditions and is independent of the activities of MnP or LiP.