Crude oil and pyrene degradation by halotolerant fungi Embellisia sp. KJ59 and Alternaria sp. KJ66 isolated from saline soils

Abstract

ABSTRACT In recent years, investigating halophilic and halotolerant fungi enzymes has confirmed their significant potential in the biodegradation of crude oil. The aim of the current study was to evaluate the biodegradation of crude oil by halotolerant fungal Embellisia sp. KJ59 and Alternaria sp. KJ66. The fungal strains were isolated on Czapek Dox Agar (CDA), potato dextrose agar (PDA), and malt extract agar (MEA) containing 10% NaCl. Seven strains that could grow in salinity, ranging from 0 to 17% were selected. Out of the seven isolates, isolates KJ59 and KJ66 were selected as superior strains because they were more efficient in the biodegradation of crude oil on Minimal Salt Medium containing 1% crude oil and different salinity. The isolates were identified as Embellisia sp. and Alternaria sp. based on its nucleotide sequence of internal transcribed spacer gene. They could biodegrade petroleum, ranging from 81.3 to 95.1% in NaCl concentrations of 0, 2.5, and 5% on PDB over a period of 14 days. Pyrene removal by these strains was over 88.3% in saline and non-saline MSM containing 100 mg L−1 pyrene. Finally, Embellisia sp. KJ59 and Alternaria KJ66 were introduced fungal strains for crude oil biodegradation as the sole or supplementary carbon source in the presence of different salt concentrations. Furthermore, they are potential fungal strains for bioremediation of crude oil in non-saline and contaminated saline environments.