Screening of Litter Decomposing Fungi for Degradation of Polycyclic Aromatic Hydrocarbons (PAH) Phenanthrene and benzo[A]pyrene

Abstract

A long-lasting, high level contamination of soil with polycyclic aromatic hydrocarbons (PAH) has in most cases resulted from the accidental disposal of wastes by the chemical industry. Large regions surrounding these centers also display a significant contamination resulting from diffusion and leakage of PAH. Transport of PAH via aerosols (e.g. on coal dust) has resulted in a low-level contamination but in deposits over large areas. These can not be detoxicated in an economical way by on-site decontamination techniques. In-situ detoxication which utilizes endogenous soil micro-organisms is limited by the inability of such organisms to degrade highly condensed PAH effectively; the organisms which have overcome this problem, wood-degrading whiterot fungi cannot be maintained in the soil in situ for the length of time necessary for decontamination. Recently, the ability of numerous ectomycorrhizal fungi to metabolize PAH has been demonstrated [1]. In the present preliminary study we report on the ability of litter-decomposing fungi (48 isolates from Central European soil and litter) belonging to 12 species (24 strains) to degrade phenanthrene and benzo[a]pyrene in a pure liquid culture.