The environmentally widespread micropollutants bisphenol A (BPA), carbamazepine (CBZ), 17α-ethinylestradiol (EE2), diclofenac (DF), sulfamethoxazole (SMX), technical nonylphenol (t-NP) and triclosan (TCS) were used to assess the potential of the laccase-producing freshwater ascomycete Phoma sp. strain UHH 5-1-03 for micropollutant removal and to provide quantitative insights into the mechanisms involved. Biotransformation rates observed with whole fungal cells followed the rank order EE2 ≫ BPA > TCS > t-NP > DF > SMX > CBZ. Biosorption onto fungal mycelia was prominent for BPA, EE2, TCS and t-NP and insignificant for CBZ, DF and SMX. Enzymatic removal rates investigated with cell-free, laccase-containing culture supernatants of Phoma sp. followed the rank order EE2 > BPA > DF > t-NP > TCS and were insignificant for SMX and CBZ. Mass spectrometry-assisted investigations addressing metabolite formation from unlabelled and (13)C6-labelled DF and SMX yielded DF metabolites indicating hydroxylation, cyclisation and decarboxylation reactions, as well as oxidative coupling typical for laccase reactions. For SMX, several products characterised by lower molecular masses than the parent compound were found, and indications for deamination and formamide formation were obtained. Summarising, the obtained results suggest that the extracellular laccase of Phoma sp. largely contributes to fungal biotransformation of EE2, BPA, DF, TCS and t-NP, together with cell-associated enzymes such as, e.g. cytochrome P450 monooxygenases suggested by the appearance of hydroxylated metabolites from DF. Laccase does not seem to play any role in the metabolisation of SMX and CBZ, where yet to be identified cell-associated enzymes have to be considered instead.

Synthetic polymers often pose environmental hazards due to low biodegradation rates and resulting accumulation. In this study, a selection of wood-rotting fungi representing different lignocellulose decay types was screened for oxidative biodegradation of the polymer polystyrene sulfonate (PSS). Brown-rot basidiomycetes showed PSS depolymerisation of up to 50 % reduction in number-average molecular mass (Mn) within 20 days. In-depth investigations with the most efficient depolymeriser, a Gloeophyllum trabeum strain, pointed at extracellular hydroquinone-driven Fenton chemistry responsible for depolymerisation. Detection of hydroxyl radicals present in the culture supernatants showed good compliance with depolymerisation over the time course of PSS degradation. 2,5-Dimethoxy-1,4-hydroquinone (2,5-DMHQ), which was detected in supernatants of active cultures via liquid chromatography and mass spectrometry, was demonstrated to drive the Fenton processes in G. trabeum cultures. Up to 80% reduction in Mn of PSS where observed when fungal cultures were additionally supplemented with 2,5-dimethoxy benzoquinone, the oxidized from of 2,5-DMHQ. Furthermore, 2,5-DMHQ could initiate the Fenton's reagent-mediated PSS depolymerisation in cell-free systems. In contrast, white-rot fungi were unable to cause substantial depolymerising effects despite the expression of lignin-modifying exo-enzymes. Detailed investigations with laccase from Trametes versicolor revealed that only in presence of certain redox mediators limited PSS depolymerisation occurred. Our results indicate that brown-rot fungi might be suitable organisms for the biodegradation of recalcitrant synthetic polymeric pollutants.

Membrane bioreactors (MBRs) augmented with terrestrial white‐rot basidiomycetes have already been tested for the removal of pharmaceutically active compounds (PhACs) from wastewaters. Within the present study, an aquatic ascomycete (Phoma sp.) was initially demonstrated to efficiently remove several PhACs at their real environmental trace concentrations from nonsterile municipal wastewater on a laboratory scale. Then, a pilot MBR was bioaugmented with Phoma sp. and successively operated in two configurations (first treating full‐scale MBR effluent as a posttreatment, and then treating raw municipal wastewater). Treatment of influent wastewater by the Phoma‐bioaugmented pilot MBR was more efficient than influent treatment by a concomitantly operated full‐scale MBR lacking Phoma sp and posttreatment of full‐scale MBR permeate using the pilot MBR. A stable removal of the PhACs carbamazepine (CBZ) and diclofenac (DF) (39 and 34% on average, respectively) could be achieved throughout the pilot MBR influent treatment period of 51 days, without the need for additional nutrient supplementation (full‐scale MBR: on average, 15% DF but no CBZ removed during 108 days). The long‐term presence of Phoma sp. in the pilot MBR could be demonstrated using fluorescence in situ hybridization analysis, but still open questions regarding its long‐term activity maintenance remain to be answered.