Bioremediation of emerging pollutants from sewage sludge by fungal bioaugmentation

Current wastewater treatment processes are not able to completely remove many organic pollutants. The increasing use of the sludge derived from wastewater treatment plants (WWTP) in agricultural lands therefore becomes a source for micropollutants to enter the environment. An eco-friendly biotechnological treatment which employs the white-rot fungus Trametes versicolor was assessed to remove several groups of pharmaceuticals at pre-existent concentrations from sewage sludge. First, two different strategies were applied in sterile conditions to demonstrate the colonization and degrading ability of the fungus: solidphase systems with dehydrated sludge and a lignocellulosic substrate, and slurry bioreactors with sludge from the outlet of an anaerobic digester, all from the same WWTP. Fungal colonization and activity were monitored with ergosterol content, laccase activity and a degradation test (ND24). The solid phase biopile treatment resulted in the complete removal of seven out of 14 detected pharmaceuticals, and between 42-80% for the remaining compounds. Meanwhile, the bioslurry reactor produced a complete elimination of eight out of 24 pharmaceutical agents detected, and 26-92% for the others. However, for the same compounds, in most of the cases the solid-phase treatment showed higher removal efficiency, plus better results in terms of reducing the toxicity of the sludge after the treatment. Next step consisted in applying T. versicolor in non-sterile sludge, which was assessed in solid-phase biopiles, considering the better fungal performance on these systems. Success in the fungal bioaugmentation was monitored by community analyses, which compared the bioaugmented (TVB) and non-bioaugmented (NB) systems. DGGE profiles revealed some inhibition caused by the fungus over bacterial community and also the predominance of T. versicolor in the TVB-systems up to 21-d (half-treatment), to later disappear by the end of the process and being replaced by other fungi. Results permitted to find the relationship of the fungal survival with the degradation of pharmaceuticals on time. Results include the identification of the most abundant bacterial/fungal taxons present in the sludge biopiles. After 42-d of treatment, removals over 50% for eight out of the nine therapeutic agents detected were obtained; only carbamazepine could not be removed at all, contrary to sterile conditions. Overall results suggest that mycoremediation is a potential strategy for the degradation of emerging pollutants from sludge.Spanish Ministries MMAMRM (project-010/PC08/3-04) and MICIN (project-CTQ2010-21776-C2-01). The Department of Chemical Engineering (UAB) is the Unit of Biochemical Engineering of the Xarxa de Referència en Biotecnologia de la Generalitat de Catalunya. Rodríguez-Rodríguez acknowledges UCR-CSIC collaboration

On stochastic partial differential equations with spatially correlated noise: smoothness of the law

AbstractWe deal with the following general kind of stochastic partial differential equations:Lu(t,x)=α(u(t,x))Ḟ(t,x)+β(u(t,x)),t⩾0,x∈Rdwith null initial conditions, L a second-order partial differential operator and F a Gaussian noise, white in time and correlated in space. Firstly, we prove that the solution u(t,x) possesses a smooth density pt,x for every t>0,x∈Rd. We use the tools of Malliavin Calculus. Secondly, we apply this general result to two particular cases: the d-dimensional spatial heat equation, d⩾1, and the wave equation, d∈{1,2}

On stochastic partial differential equations with spatially correlated noise: smoothness of the law

We deal with the following general kind of stochastic partial differential equations:with null initial conditions, L a second-order partial differential operator and F a Gaussian noise, white in time and correlated in space. Firstly, we prove that the solution u(t,x) possesses a smooth density pt,x for every . We use the tools of Malliavin Calculus. Secondly, we apply this general result to two particular cases: the d-dimensional spatial heat equation, d[greater-or-equal, slanted]1, and the wave equation, d[set membership, variant]{1,2}.Stochastic partial differential equation Wave and heat equation Gaussian noise Malliavin Calculus

Mechanism of textile metal dye biotransformation by Trametes versicolor

7 pages, 4 figures, 1 table.-- PMID: 15087198 [PubMed].-- Printed version published Apr 2004.The biodegradation of Grey Lanaset G, which consists of a mixture of metal complexed dye, was studied. Experiments were carried out in a bioreactor with retained pellets of the fungus Trametes versicolor that was operated under conditions of laccase production. Although decolorization was highly efficient (90%), no direct relationship to extracellular enzyme was apparent. Moreover, the extracellular enzyme was found to be unable to degrade the dye in vitro. The process involves several steps. Thus, the initial adsorption of the dye and its transfer into cells is followed by breaking of the metal complex bond in the cells release of the components. The metal (Cr and Co) contents of the biomass and treated solutions, and their closer relationship to intracellular enzyme and degradation of the dye, confirm the initial hypothesis.This work was funded by the Spanish Commission of Science and Technology (Project PPQ2000-0645-C02-01) and the AGBAR Foundation (Spain).Peer reviewe

Biodegradation of Polybrominated Diphenyl Ethersin Liquid Media and Sewage Sludge by Trametes versicolor

Polybrominated diphenyl ethers (PBDE) are widely employed as flame retardants and constitute a group of emerging pollutants of high persistence. The degradation of different PBDE commercial mixtures (penta-, octa- and deca-BDE) by the white-rot fungus Trametes versicolor under aerobic conditions was studied. This work demonstrates the capacity of T. versicolor to degrade three different PBDE commercial mixtures in aqueous phase, obtaining final removal efficiencies of 87±6, 85±13 and 67±7% for deca-, pentaand octa-BDE mixtures (and minimal degradation of 73±5, 38±13, and 28±7%), respectively. The intracellular enzymatic complex cytochrome P-450 is proposed as the enzyme involved in the first step of deca-BDE degradation by T. versicolor. In an effort to assay the application of the fungus in real contaminated matrices, the study successfully demonstrated the ability of T. versicolor to degrade pre-existent deca-BDE from sewage sludge in a solid-phase treatment, reaching 86% elimination at the end of the process. The findings support the potential use of the ligninolytic fungus in bioremediation of PBDE.Ministerio de Medio Ambiente y Medio Rural Marino/[010/PC08/3-04]/ MAMRM/EspañaConsolidated Research Groups of Catalonia/[(2009-SGR-656]//EspañaConsolidated Research Groups of Catalonia/[(2009-SGR-796]//EspañaUniversitat Autònoma de Barcelona/[]/UAB/EspañaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro en Investigación en Contaminación Ambiental (CICA

Fungal biodegradation of the N-nitrosodimethylamine precursors venlafaxine and O-desmethylvenlafaxine in water

Antidepressant drugs such as Venlafaxine (VFX) and O-desmethylvenlafaxine (ODMVFX) are emerging contaminants that are commonly detected in aquatic environments, since conventional wastewater treatment plants are unable to completely remove them. They can be precursors of hazardous by-products, such as the carcinogenic N-nitrosodimethylamine (NDMA), generated upon water chlorination, as they contain the dimethylamino moiety, necessary for the formation of NDMA. In this study, the capability of three white rot fungi (Trametes versicolor, Ganoderma lucidum and Pleurotus ostreatus) to remove both antidepressants from water and to decrease NDMA formation potential was investigated. Furthermore, transformation by-products (TPs) generated along the treatment process were elucidated and also correlated with their NDMA formation potential. Very promising results were obtained for T. versicolor and G. lucidum, both being able to remove up to 100% of ODMVFX. In the case of VFX, which is very recalcitrant to conventional wastewater treatment, a 70% of removal was achieved by T. versicolor, along with a reduction in NDMA formation potential, thus decreasing the associated problems for human health and the environment. However, the NDMA formation potential remained practically constant during treatment with G. lucidum despite of the equally high VFX removal (70%). This difference was attributed to the generation of different TPs during both fungal treatments. For example, G. lucidum generated more ODMVFX, which actually has a higher NDMA formation potential than the parent compound itself. © 2018 Elsevier LtdThis work was supported by the Spanish Ministry of Economy, Industry and Competitiveness (project CTQ2010-21776-C02 and CTM2013-48545-C2), co-financed by the European Union through the European Regional Development Fund (ERDF) and supported by the Generalitat de Catalunya (Consolidated Research Groups: Catalan Institute for water Research 2014 SGR 291 and 2014 SGR 476). The Department of Chemical, Biological and Environmental Engineering of the Autonomous University of Barcelona (UAB) is member of the Xarxa de Referència en Biotecnologia de la Generalitat de Catalunya. Castellet-Rovira, F. acknowledges a predoctoral grant from UAB. Dr. SRM acknowledges her Ramón y Cajal fellowship (RyC-2014-16707) and Dr. MJF acknowledges her Ramón y Cajal fellowship (RyC-2015-17108) from the Spanish Ministry of Economy, Industry and Competitiveness. Dr. MJF acknowledges the European Commission for funding project 623711 under the FP7-PEOPLE-2013-IIF - Marie Curie Action: “International Incoming Fellowships”. Adrián Jaén-Gil acknowledge their PhD scholarship from AGAUR (2017FI_B 00778). Pleurotus ostreatus (NCBI KJ020935) cultures were kindly provided by Laura Palli.Peer reviewe