Plastics are widely used around the world, but due to poor recycling methods and low reuse, tonnes of undegraded plastic accumulate in terrestrial and marine ecosystems. Biodegradation by microorganisms and microbial enzymes is one of the degradation processes that needs to be improved in the future. In the master's thesis, we searched for fungi that degrade selected types of plastics (polyamide, polyethylene, polyethylene terephthalate, polypropylene, and polyurethane) among extremotolerant fungi isolated from car repair shops and gas stations, from microniches where water and petroleum products are mixed. We also looked for fungi that can degrade textiles containing synthetic fibres. Using gas chromatography, we determined the concentration of CO2 released in the bottles in which the fungi grew in the medium with plastic, and in the bottles in which the fungi grew in the medium without plastic and compared the results. All strains were also inoculated into media with synthetic fibres, which were examined microscopically after incubation to verify the growth. The four fungal strains most promising for plastic degradation were from the genera Penicillium, Peterozyma and Rhodotorula. They were further tested on each plastic separately and inoculated onto two types of synthetic textile. In all cases, the growth was observed under the microscope. Of these four fungi, two (Peterozyma toletana, Rhodotorula diobovata) have not been identified as plastic decomposers in previous studies, and we have demonstrated the degradation of polypropylene by Penicillium citrinum, a fungus that has not yet been demonstrated.
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