The Potential of White-rot Fungi in Bioremediation

The Iignin-degrading enzyme system of white-rot fungi, which are mostly basidiomycetes, has been studied intensively in recent years. The extracellular component of the system is comprised of Iignin peroxidase, manganese peroxidase, glyoxal oxidase and certain metabolites. Lignin is fragmented by this system, and the plethora of degradation products taken up by the hyphae and further metabolized by the intracellular system. The intracellular system has received very little research attention. The structural complexity and heterogeneity of Iignin show in fact that this enzyme system is so nonspecific that it also degrades a variety of hazardous compounds, including polycyclic aromatics, some polychlorinated biphenyls and dioxins, DDT, and many chlorinated phenols. Using pentachlorophenol (PCP) as a model substrate, we have studied the possibility of using white-rot fungi to remediate soils contaminated with hazardous compounds. Successful laboratory results led to a field study in the summer of 1989. Results showed that the laboratory findings could be duplicated in the field.