Biodegradation of lindane pesticide by non white- rots soil fungus Fusarium sp.
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Lindane or γ- hexachlorocyclohexane (γ-HCH) is a chlorinated pesticide and its toxic effects on biota necessitate its removal. Microbial degradation is an important process for pesticide bioremediation and the role of soil fungi in recycling of organic matter prompted us to study the biodegradation of lindane using fungi. This study aims at enrichment, isolation and screening of soil fungi capable of metabolizing lindane. Two Fusarium species (F. poae and F. solani) isolated from the pesticide contaminated soil showed better growth on the plates supplemented with lindane as a sole carbon source, when compared with the growth performance of other fungal isolates from the same contaminated soil. However, ANOVA revealed a significant difference in fungal biomass production in both F. poae (F = 22.02; N = 15; P < 0.001) and F. solani (F = 268.75; N = 15; P < 0.001) across different lindane concentrations (0–600 μg ml−1). Growth of both Fusarium sp. was maximum at a lindane concentration of 100 μg ml−1, while minimum at 600 μg ml−1 concentrations. Results on the time dependent release of chlorine by the Fusarium strains in the presence of various concentration of lindane showed the highest mineralization of the pesticide on 10th day of incubation. Time dependent variations in the release of chlorine from 1st to 10th day by both the selected fungal strains were found to be statistically significant. A significant positive relationship exists between fungal biomass increase and chlorine release existed for both F. solani (R² = 0.960) and F. poae (R² = 0.628). The results of gas chromatograph analysis of γ- HCH confirmed the biodegradation and utilization of γ- HCH by F. poae and F. solani. The data on lindane degradation by the two fungal strains demonstrated that the biodegradation of lindane by F. solani (59.4%) was slightly higher than that by the F. poae (56.7%).
KeywordsBioremediation Free chlorine Fungi Lindane Soil
We are thankful to Dr. S. K. Diwedi (Associate Professor, Department of Environmental Science, Babasaheb Bhimrao Ambedkar University, Lucknow) for his supports during identification of fungal isolates. Financial support to Ms Veena as a Rajiv Gandhi National Fellowship provided by Union Grant Commission, New Delhi is gratefully acknowledged.
- Bhuyan S, Sreedharan B, Adhya TK, Sethunathan N (1992) Accelerated aerobic degradation of γ- bodegradation of Hexachlorocyclohexane isomers in water and soil slurry. J Agric Food Chem 50:5070–5076Google Scholar
- Fretzner S, Lingens F (1994) Bacterial dehalogenases: biochemistry, genetics and biotechnological applications. Microbiol rev 58:641–685Google Scholar
- Gilman JC (1959) A manual of soil fungi. Iowa State College Press, AmesGoogle Scholar
- Hestberg H, Willumsen P, Christensen M, Andersen O, Jacobsen C (2003) Bioaugmentation of tar-contaminated soil under field condition using Pleurotus ostreatus refuse from commercial mushroom production. Environ Toxicol Chem 22:692–698Google Scholar
- Hewitt HG (1998) Fungicide in crop protection. CAB International, UKGoogle Scholar
- Mougin C, Pericaud C, Malosse C, Laugero C, Ashter M (1999) Biotransformation of the insecticide hexachlorocyclohexane in suspension of flooded and non- flooded soil pretreated with hexachlorocyclohexane. Biol Fert Soils 12:279–284Google Scholar
- Pointing S (2001) Feasibility of bioremediation by white rot fungi. Appl Microbiol Biotechnol 75:313–321Google Scholar