Assessment of degradation potential of aliphatic hydrocarbons by autochthonous filamentous fungi from a historically polluted clay soil

• Published in: The Science of the total environment 2015-02, Vol.505, p.545-554
• Main Authors: Covino, Stefano, D'Annibale, Alessandro, Stazi, Silvia Rita, Cajthaml, Tomas, Čvančarová, Monika, Stella, Tatiana, Petruccioli, Maurizio
• Format: Article
• Language: English
• Subjects: Aliphatic hydrocarbons; Ascomycetes; Bioavailability; Biodegradation, Environmental; Bioremediation; Biostimulation; Carbon; Clay (material); Degradation; Density; Folsomia candida; Fungi; Fungi - metabolism; Hydrocarbons - analysis; Hydrocarbons - metabolism; Mycoaugmentation; Oil-contaminated soil; Pseudoallescheria sp; Soil (material); Soil - chemistry; Soil Microbiology; Soil Pollutants - analysis; Soil Pollutants - metabolism; Soil remediation; Triticum aestivum
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2014.10.027

The present work was aimed at isolating and identifying the main members of the mycobiota of a clay soil historically contaminated by mid- and long-chain aliphatic hydrocarbons (AH) and to subsequently assess their hydrocarbon-degrading ability. All the isolates were Ascomycetes and, among them, the most interesting was Pseudoallescheria sp. 18A, which displayed both the ability to use AH as the sole carbon source and to profusely colonize a wheat straw:poplar wood chip (70:30, w/w) lignocellulosic mixture (LM) selected as the amendment for subsequent soil remediation microcosms. After a 60d mycoaugmentation with Pseudoallescheria sp. of the aforementioned soil, mixed with the sterile LM (5:1 mass ratio), a 79.7% AH reduction and a significant detoxification, inferred by a drop in mortality of Folsomia candida from 90 to 24%, were observed. However, similar degradation and detoxification outcomes were found in the non-inoculated incubation control soil that had been amended with the sterile LM. This was due to the biostimulation exerted by the amendment on the resident microbiota, fungi in particular, the activity and density of which were low, instead, in the non-amended incubation control soil. •All fungal isolates from an oil-polluted soil were Ascomycetes.•High clay content and historical contamination made the soil untreatable.•79% AH reduction was observed in soil augmented with Pseudoallescheria sp.•Contaminant bioavailability was estimated by a method relying on SFE with CO2.•Biodegradation extents of AH exceeded their respective bioavailable fraction.