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Mycoremediation of Oily Slime Containing a Polycyclic Aromatic Hydrocarbon Mixture

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Abstract

Purpose

Polycyclic aromatic hydrocarbons (PAHs) are waste products, which today represent a serious problem in the world due to their high toxicity and difficult removal from the environment. For these reasons, they represent an important and challenging topic of study and research. PAHs may be degraded through biotic pathways including both aerobic and anaerobic degradation by bacteria, fungi, cyanobacteria and eukaryotic algae. In recent decades, fungi have proven very useful in the biodegradation of some of more toxic PAHs, such as anthracene, pyrene, benzo[a]pyrene and fluorene. However, there is a lack of information from an application point of view. This paper sheds light on real-world, polluted matrices that can be degraded by fungi.

Methods

Fifteen fungal species were isolated from an oily slime derived from waste products of naval activities and screened to assess their ability to degrade PAH mixtures. The most suitable fungal strains were employed in the degradation treatment.

Results

A set of selected microfungi (including Fusarium solani along with a fungal consortium of Pseudallescheria boydii, Talaromyces amestolkiae and Sordaria fimicola) was shown to degrade PAHs better than the other fungi considered. The greatest degradation activity was observed during the first week of treatment.

Conclusions

The significant relevance of exploiting native fungi to recover marine and terrestrial areas contaminated by PAHs was shown. Moreover, the use of selected fungi isolated from the same contaminated substrate is highly effective in the mycoremediation of recalcitrant pollutants such as oily slime containing PAHs mixture.

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Acknowledgements

The authors would like to thank Eurochem Italia for the collaboration in the chemical analysis. The research was performed in the framework of the PhD STAT (Scienze e Tecnologie per l’Ambiente e il Territorio) curricula in Biology Applied to Agriculture and Environment (University of Genoa, DISTAV) and partially supported with internal funds.

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Greco, G., Di Piazza, S., Cecchi, G. et al. Mycoremediation of Oily Slime Containing a Polycyclic Aromatic Hydrocarbon Mixture. Waste Biomass Valor 10, 3821–3831 (2019). https://doi.org/10.1007/s12649-019-00802-x

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