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Biodegradation of C20 carbon clusters from Diesel Fuel by Coriolopsis gallica: optimization, metabolic pathway, phytotoxicity

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Abstract

This study is to test the capacity of the white rot fungus Coriolopsis gallica for the biodegradation of Diesel Fuel hydrocarbons (DHs). Using the experimental face centered central composite design (FCCCD), culture conditions of the Diesel-mended medium were optimized to reach 110.43% of DHs removal rate, and l5267.35 U L−1 of laccase production by C. gallica, simultaneously. The optimal combination of the cultural parameters was: Diesel concentration range of 2.95–3.14%, inoculum size of 3%, incubation time of 15 days, Tween 80 concentration of 0.05%, and the ratio glucose/peptone (G/P) range of 10.15–10.27. Further, the degradation ability of C. gallica for Diesel Fuel was evaluated through mycelial pellets uptake and oxidative action of fungal enzymes in the optimized degrading-medium using gas chromatography–mass spectrometry (GC–MS). Cyclosiloxanes and C20 PAHs detected as the major compound in Diesel Fuel (46%) was completely bio-transformed to simple metabolites including, essentially benzoic acid ester (71%), alcohols (1.52%) epoxy alkane (1.07%), carboxylic acids (1.24%) and quinones (0.33%). Germination rate and root elongation, as a rapid phytotoxicity test demonstrated that toxicity of Diesel’s PAHs is minimized by fungal treatment.

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Acknowledgements

All the authors acknowledge and thank the Chemical Department of the Faculty of Sciences and Arts of Khulais, for allowing the use of spectrophotometer and Dr. Nada M. Doleib (Faculty of Sciences and Arts, Khulais, Jeddah) for helping to obtain the Diesel fuel from Saudi Aramco. Also we thank Mr. Mahmoud Daassi [English Teacher, Sultanate of Oman, Dhofar Region] to check English.

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Authors and Affiliations

  1. Department of Biology, Faculty of Sciences and Arts, Khulais, University of Jeddah, Jeddah, Saudi Arabia

    Dalel Daâssi & Salwa Bawasir

  2. Laboratory of Biochemistry and Enzymatic Engineering of Lipases, National School of Engineers of Sfax, University of Sfax, 3038, Sfax, Tunisia

    Fakher Frikha & Tahar Mechichi

  3. Forest Ecology Laboratory, National Research Institute in Rural Engineering, Water and Forestry, University of Carthage, Tunis, Tunisia

    Afef Nasraoui-Hajaji

  4. Research Unit of Nitrogen Nutrition and Metabolism and Stress-Related Proteins, Tunisian Faculty of Sciences, University of Tunis El Manar, 1060, Tunis, Tunisia

    Afef Nasraoui-Hajaji

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  1. Dalel Daâssi
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Daâssi, D., Nasraoui-Hajaji, A., Bawasir, S. et al. Biodegradation of C20 carbon clusters from Diesel Fuel by Coriolopsis gallica: optimization, metabolic pathway, phytotoxicity. 3 Biotech 11, 214 (2021). https://doi.org/10.1007/s13205-021-02769-w

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