Richard T. Lamar

Binding of pentachlorophenol to humic substances in soil by the action of white rot fungi

The fate of 14C-pentachlorophenol (14C-PCP) in soil inoculated with each of four wood degrading fungi was studied. After 9 wk of incubation with the fungi, the majority of the 14C (between 34 and 65%) was found bound to humic (HA), fulvic acid (FA) and humin, with lesser amounts found in the organic-extractable fraction or mineralized. The highest amounts of PCP were bound to HA (20–36%, compared to 7.5–8.3% in the uninoculated controls). Binding to FA and to humin was lower, ranging between 8.7 and 17.5% and 4.8 and 11.1%, respectively, in the fungal cultures. In control experiments around 5% of the radioactivity was found associated to FA and between 2 and 4% to the humin. The highest binding of PCP to the humic materials was obtained with Pleurotus ostreatus, followed by Irpex lacteus, Trametes versicolor and Bjerkandera adusta. Mineralization of PCP from soil cultures by the fungi was low. The fungus that mineralized the most PCP was T. versicolor, converting 8.8% of 14C-PCP into 14CO2, compared to 0.6% mineralized in the uninoculated controls. Methylation of PCP to pentachloroanisole by the fungi was low, ranging between 0 and 6.8% after 9 wk.

The role of fungal lignin-degrading enzymes in xenobiotic degradation

Abstract Recent studies have reported the first pathways for the degradation of important xenobiotics by lignin-degrading fungi, and have elucidated the role that lignin peroxidases and manganese-dependent peroxidases play both in these pathways and in the decolorization of pulp bleach plant effluents.

White Rot Fungi in the Treatment of Hazardous Chemicals and Wastes

Microbiological treatment of hazardous wastes has generally been associated with the use of bacteria. However, during the past decade a significant body of evidence has accumulated that demonstrates that fungi, in particular lignin-degrading or white-rot fungi, have the ability to degrade a wide range of hazardous organic compounds and thus might also be useful for treatment of materials contaminated with these compounds.

Treatability study using Phanerochaete sordida for the bioremediation of DDT contaminated soil

A treatability study was conducted to determine the potential of white rot fungi to remediate soil from a Superfund site that had been contaminated with DDT. A tiered approach was utilized, starting with simple laboratory studies to screen the potential of white rot fungal strains to degrade DDT and culminating with a soil pan study that simulated land farming. Results from early tiers of the study indicated that Phanerochaete sordida had the best potential for remediating the soil. In the soil pan study, the fungus ultimately grew very well after second inoculation. However, the good growth did not translate to higher DDT removal compared to removal in pans that were not inoculated. 14[DDT] fate studies indicated the small amount of removal that did occur for both fungal inoculated and non‐inoculated conditions could be partially attributed to incorporation into humic material. Addition of a surfactant to the soil enhanced the removal of DDT in both inoculated and non‐inoculated soil. Consequently, under...