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Edible fungi are a valuable resource in the search for sustainable solutions to environmental pollution. Their ability to degrade organic pollutants, extract heavy metals, and restore ecological balance has a huge potential for bioremediation. They are also sustainable food resources. Edible fungi (basidiomycetes or fungi from other divisions) represent an underutilized resource in the field of bioremediation. By maximizing their unique capabilities, it is possible to develop innovative approaches for addressing environmental contamination. The aim of the present study was to find selective chemical agents suppressing the growth of microfungi and bacteria, but not suppressing white-rot fungi, in order to perform large-scale cultivation of white-rot fungi in natural unsterile substrates and use it for different purposes. One application could be the preparation of a matrix composed of wooden sleeper (contaminated with PAHs) and soil for further hazardous waste bioremediation using white-rot fungi. In vitro microbiological methods were applied, such as, firstly, compatibility tests between bacteria and white-rot fungi or microfungi, allowing us to evaluate the interaction between different organisms, and secondly, the addition of chemicals on the surface of a Petri dish with a test strain of microorganisms of white-rot fungi, allowing us to determine the impact of chemicals on the growth of organisms. This study shows that white-rot fungi are not compatible to grow with several rhizobacteria or bacteria isolated from soil and bioremediated waste. Therefore, the impact of several inorganic materials, such as lime (hydrated form), charcoal, dolomite powder, ash, gypsum, phosphogypsum, hydrogen peroxide, potassium permanganate, and sodium hydroxide, was evaluated on the growth of microfungi (sixteen strains), white-rot fungi (three strains), and bacteria (nine strains) in vitro. Charcoal, dolomite powder, gypsum, and phosphogypsum did not suppress the growth either of microfungi or of bacteria in the tested substrate, and even acted as promoters of their growth. The effects of the other agents tested were strain dependent. Potassium permanganate could be used for bacteria and Candida spp. growth suppression, but not for other microfungi. Lime showed promising results by suppressing the growth of microfungi and bacteria, but it also suppressed the growth of white-rot fungi. Hydrogen peroxide showed strong suppression of microfungi, and even had a bactericidal effect on some bacteria, but did not have an impact on white-rot fungi. The study highlights the practical utility of using hydrogen peroxide up to 3% as an effective biota-suppressing chemical agent prior to inoculating white-rot fungi in the large-scale bioremediation of polluted substrates, or in the large-scale cultivation for mushroom production as a foodstuff. [ABSTRACT FROM AUTHOR]

Wooden sleepers used in railways are impregnated with preservatives with fungicidic and bactericidic properties, which contain a large amount of harmful polycyclic aromatic hydrocarbons (PAHs). The aim of this research was to reveal the type of fungi in the rhizosphere of plants, which tolerate pollutants and can be involved in bioremediation process of creosote-contaminated used wooden railway sleepers. Tagetes patula grown in the substrate with 12.5% creosote impregnated used wooden sleepers chips additive is characterized by the most intensive root development and the biggest population of active fungi, therefore it is recommended for further investigation. Number of colonies of fungi in the rhizosphere of investigated plants decreased in many cases by increasing the amount of sleepers chips additive in substrate, however it was greater in the substrates with creosote treated wooden sleepers chips additives (12.5, 25 and 37.5% wooden sleepers chips) than in the pure substrate and various substrates with additives of pure Pinus sylvestris chips. This is a pioneering study searching for the local fungi species in Lithuania, which can be further utilized for the bioremediation of PAHs. [ABSTRACT FROM AUTHOR]

A group of 36 fungal strains, belonging to the Lithuanian mycobiota, was collected and isolated from different locations, habitats, and matrices, including creosote-treated wood in storage yards for crosstie wastes. The eight most perspective strains selected according to preliminary assessment of tolerance to coal tar were subsequently identified combining taxonomical evaluation and molecular techniques. The tolerance of the eight identified fungal species (five basidiomycetes and three ascomycetes) to the presence of various concentrations of coal tar, and for the four most perspective fungal strains (Pleurotussp.,Schizophyllumsp.,Irpex lacteus,Bjerkandera adusta) to polycyclic aromatic hydrocarbons was evaluated. The ligninolytic enzymatic activity assay of the isolated strains resulted in a good correspondence between the tolerance to pollutants and the capability to produce ligninolytic enzymes indicating that this group of white-rot fungi is perspective for further investigation and eventual usage for mycoremediation of polycyclic aromatic hydrocarbons polluted substrates. [ABSTRACT FROM AUTHOR]

The wood preservatives have been extensively used in the last few decades to enhance the life expectancy of woody materials for external uses against natural and biological decay. The popular waste disposal options available for these expended materials nowadays, such as burning and land filling are not acceptable due to economic, health and environmental concerns. The development of alternative and environmental friendly methods for disposal of these waste materials is of major importance. Recently the use of microorganisms, such as white-rot fungi, capable to tolerate and / or degrade high pollutant concentrations for their chemical transformation into less hazardous compounds through Solid State Fermentation (SSF) processes has been seriously investigated. This presentation discusses a novel approach for bioremediation of creosote-treated railways wood sleepers by Solid State Fermentation of white-rot fungi and the possibility to combine it sequentially with phytoremediation in the frame of the EUSF A project VP-3.1- MM-10V- 02_010 (BIOREM). [ABSTRACT FROM AUTHOR]