Tolerance to cytostatic drugs bleomycin and vincristine by white rot fungi

Cytostatic drugs have become one of the greatest environmental hazards. They exhibit toxic, carcinogenic, mutagenic and teratogenic effects on flora and fauna, including people. They are poorly eliminated in conventional wastewater treatment plants and their mixtures could possess higher ecotoxicity than individual drugs. Fungi are organisms with enormous potential for biodegradation of a variety of toxic chemical pollutants. The aim of this work was to estimate tolerance of five fungal strains to selected anticancer drugs, which will be useful to determine the potential for their possible use in cytostatics removal and may be significant in the context of wastewater treatment application. Test was conducted on Fomes fomentarius (CB13), Hypholoma fasciculare (CB15), Phyllotopsis nidulans (CB14), Pleurotus ostreatus (BWPH) and Trametes versicolor (CB8) and the chosen drugs were bleomycin and vincristine. Their ability to grow in the presence of selected cytostatics was evaluated in cultures conducted on two solid media which differed in the richness of nutrient compounds. Fungal strains tolerance was expressed as a half maximal effective concentration. Results showed that fungi display better tolerance to high cytostatics’ concentrations in the medium rich in carbon source. Regardless of the medium used, the differences in growth ability were lower for bleomycin (the tolerance was higher). The greatest tolerance for bleomycin was shown by Pleurotus ostreatus. Results suggest that more efficient elimination of bleomycin would be possible to obtain, strain BWPH seems to be the best fungal candidate for this drug degradation assay and, probably, in wastewater treatment application tests in a longer perspective.