A comprehensive review on the application of mycoremediation in polychlorinated biphenyls treatment

Abstract

In the last decades, there has been a growing concern regarding the remediation andrecovery of polychlorinated biphenyls (PCBs) contaminated sites. The technologies traditionallyused are often energy-intensive, resource-heavy, and highly disruptive to the environments beingtreated. In this context, mycoremediation has emerged as a highly sought-after alternative due tothe efficiency of certain fungal strains in achieving high removal percentages. This review providesan overview of mycoremediation strategies for PCB bioremediation. We begin by outlining theecotoxicological challenges posed by PCB usage and traditional methods employed forremediating contaminated areas. Secondly, we present different approaches to mycoremediationof PCBs. The use of native PCB-degrading fungi shows that some strains belonging to thePenicillium, Fusarium, and Scedosporium genera are capable of removing over 70% of differentPCBs congeners. Alternatively, we discuss using white rot fungi (WRF) due to their potential intransforming PCBs and associated metabolites. Strains belonging to this group, such as Pleurotuspulmonarius, can attain PCBs removal rates above 90% with a 10.27% reduction in toxicity.Additionally, cases demonstrating the application of WRF in long-term polluted soil and water arepresented as field examples. A trickle bed pilot-scale bioreactor approach using Pleurotusostreatus obtained an average PCBs removal of 89 ± 9% for contaminated groundwater. Similarly,microcosm experiments using P. ostreatus and Irpex lacteus removed up to 50.5% and 41.3% ofPCBs content in long-term contaminated soils, respectively. We also highlight the role ofextracellular ligninolytic enzymes, such as lacasses, lignin peroxidases, manganese peroxidase,manganese-independent peroxidase, and internal oxidoreductases in the PCBs metabolismcarried out by WRF. Finally, we conclude with a series of factors to consider when implementingthese techniques for remediating polluted sites, including up-scaling, current regulations, andcombination with other remediation techniques.