Dissipation of polycyclic aromatic hydrocarbons (PAHs) in soil microcosms amended with mushroom cultivation substrate

The potential of mushroom cultivation substrate (MCS) in bioremediation was examined in polycyclic aromatic hydrocarbon (PAH)-contaminated soil. After a 60-day incubation, 32.9% dissipation of the 15 studied PAHs was observed in MCS-amended microcosms, with anthracene, benzo(a)pyrene and benzo(a)anthracene being the most degradable PAHs. MCS significantly increased the abundance and changed the community compositions of bacteria, fungi and aromatic hydrocarbon degraders. Two species belonging to the Sordariomycetes of the Ascomycota were enriched in all MCS-treated soil samples, and coupled with the unique changes in the PAH profile, this implies the involvement of laccase-like enzymes. Limited improvement was observed after adding Pleurotus ostreatus, possibly because of its poor colonization of the soil. In addition, alfalfa appeared to antagonize the bioremediation effects of MCS. The results of this study suggest that MCS can be a cost-effective and green biostimulation agent, thereby providing support for the development of MCS-based biostimulation of PAH-contaminated soil.