Biodegradation of diuron in artificially contaminated water and seawater by wood colonized with the white-rot fungus Trametes versicolor

Abstract

We investigated the potential of white-rot fungi for bioremediation of aqueous environments contaminated with diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea). First, diuron degradation activities of several white-rot fungi (Ceriporia lacerata, Phanerochaete chrysosporium, Phanerochaete sordida, Trametes versicolor) and a brown-rot fungus (Gloeophyllum trabeum) were evaluated under low- or high-nitrogen conditions. While G. trabeum showed hardly any degradation activity, white-rot fungi except for C. lacerata showed degradation activity, at least under some conditions. In particular, the activity of T. versicolor was high regardless of culture conditions (30–35% degradation at both levels of nitrogen). T. versicolor degraded diuron to two metabolites, 1-(3,4-dichlorophenyl)-3-methylurea and 1-(3,4-dichlorophenyl)urea, and did not accumulate the highly toxic metabolite 3,4-dichloroaniline. Moreover, the diuron content of artificially contaminated water dramatically decreased from 1.0 to 0.012 µM and artificially contaminated seawater (3.4% sea salt, w/v) decreased to 0.405 µM after incubation for 2 weeks with shaking on T. versicolor-colonized wood medium. These results indicated that wood medium colonized with white-rot fungi may be applicable for bioremediation and detoxification of diuron-contaminated aqueous environments.