Rhizoremediation of hydrocarbon contaminated soil using Luffa aegyptiaca (Mill) and associated fungi

Abstract

The potentials of Luffa aegyptiaca and its rhizospheric, non-mycorrhizal fungi in biodegrading and bio-remediating hydrocarbon contaminated soil were investigated in-vitro and in-situ. Biodegradation study was done in two stages: preliminary study using hydrocarbon treated filter paper and in-vitro with Mineral Salt Media (MSM) read on Spectrophotometer at two photo synthetically active wavelengths (530 nm and 620 nm) while rhizoremediation study was done in-situ in contaminated plot of land. Hydrocarbon utilization ability of the fungi and plant were confirmed using total petroleum hydrocarbon (TPH) analysis and gas chromatography mass spectroscopy (GC-MS). Results show differing rates of hydrocarbon utilization by isolated fungi. In-vitro biodegradation study showed that Aspergillus niger, Fusarium solani, Curvularia lunata and Trichoderma harzianum were best in degrading kerosene (78%), diesel (70%), spent engine oil (83%) and crude oil (77%) respectively. Rhizoremediation study using L. aegyptiaca and C. lunata show that remediation was enhanced to 72.15% as against 32.32% and 14% when only the plant or fungus is used respectively. Hydrocarbon accumulation by L. aegyptiaca also decreased in the presence of the fungus. Curvularia lunata is shown in this study to enhance the germination, survival, growth and bioremediation efficiency of L. aegyptiaca in polluted environment.

Novelty statement The potentials of Curvularia lunata, a non-mycorrhizal fungi associated with L. aegyptiaca in survival, growth and phytoremediation of petroleum hydrocarbon polluted soil by L. aegyptiaca is highlighted in this study. Luffa aegyptiaca and its associated fungi is shown to bio-remediate petroleum hydrocarbon through phyto-accumulation and rhizosphere effect.

Keywords:

• Characterization
• fungi
• Luffa aegyptiaca
• hydrocarbon
• rhizoremediation

Acknowledgments

The authors acknowledge the Department of Botany, University of Lagos and Department of Biological Sciences, Yaba College of Technology for permission to use their Laboratories during the study.

Disclosure statement

No potential conflict of interest was reported by the author(s).