Ex-Situ Studies on Biodegradation of Artificially Enriched Kerosene and Diesel Soils by Fungal Isolates

Abstract

To demonstrate the potential of biodegradation of soils enriched with kerosene and diesel, an exsitu study with the objective of evaluating and comparing the effects of three different fungal isolates P. janthenillum, P. decumbens and A. terreus was performed. The study dealt with the biodegradation of artificially enriched kerosene and diesel soils by 5%, 10% and 15% (w/w). The experiment was performed by ex-situ large scale tray method using 24 plastic trays 6" X 3" X 1" in each containing 60 kg enriched soil. After 8 weeks of inoculation of the fungal isolates, P. janthinellum found to be potential compared to the other two and displayed the highest kerosene Downloaded by [University of Otago] at 20:18 22 July 2015 ACCEPTED MANUSCRIPT ACCEPTED MANUSCRIPT 2and diesel degradative capacity resulting 98.29%, 97%, 96% and 82%, 70% and 62% degradation at 5, 10 and 15% kerosene and diesel enriched soils after 45 and 60 days respectively. Moreover, the total fungal population was found to increase as a function of time. A first-order kinetic model equation showed that the specific biodegradation rate constant 'k' value were 0.1023 and 0.0285 day -1 for 5% kerosene and diesel enrichment by P. janthinellum treatment strategy which was comparatively higher than the values for other two organisms tested. Thus, the degree of effectiveness of these bioremediation strategies in the soils enriched with kerosene and diesel is in the following order: P. janthenillum>P. decumbens>A. terreus.