Bioremediation
Bioremediation is the use of microorganism metabolism to remove pollutants. Technologies can be generally classified as in situ or ex situ. In situ bioremediation involves treating the contaminated material at the site, while ex situ involves the removal of the contaminated material to be treated elsewhere. Some examples of bioremediation technologies are phytoremediation, bioventing, bioleaching and land farming, bioreactor, composting, bioaugmentation, rhizofiltration and biostimulation.
Bioremediation can occur on its own (natural attenuation or intrinsic bioremediation) or can be spurred on via the addition of fertilizers to increase the bioavailability within the medium (biostimulation). Recent advancements have also proven successful via the addition of matched microbe strains to the medium to enhance the resident microbe population’s ability to break down contaminants. Microorganisms used to perform the function of bioremediation are known as bioremediators. Heavy metals such as cadmium and lead are not readily absorbed or captured by the bioremediators. The assimilation of metals such as mercury into the food chain may lead to affect living beings. Phytoremediation is useful in these circumstances because natural plants or transgenic plants are able to bioaccumulate these toxins in their above-ground parts, which are then harvested for removal. The heavy metals in the harvested biomass may be further concentrated by incineration or even recycled for industrial use.
The use of genetically engineered to create organisms specifically designed for bioremediation has great potential. The bacterium Deinococcus radiodurans (the most radioresistant organism known) has been modified to consume and digest toluene and ionic mercury from highly radioactive nuclear waste. During bioremediation (biodegradation) processes, fertilizer/nutrient supplementation is introduced to the environments in efforts to maximize growth and production potential. Mycoremediation is a form of bioremediation in which fungi are used to decontaminate the area.The fungi usually decomposes which is performed by mycelia as they secretes extracellular enzymes and acids which helps to break the lignin cellulose that main parts of plant fibre.
References
“Terra Nova’s Environmental Remediation Resuources”. Terranovabiosystems.com. 2009-08-31. Retrieved 2011-03-22.
Meagher, RB (2000). “Phytoremediation of toxic elemental and organic pollutants”. Current Opinion in Plant Biology 3 (2): 153–162. doi:10.1016/S1369-5266(99)00054-0.PMID 10712958.
Diaz E (editor). (2008). Microbial Biodegradation: Genomics and Molecular Biology (1st ed.). Caister Academic Press. ISBN 1904455174. ISBN 978-1-904455-17-2.
Lovley, DR (2003). “Cleaning up with genomics: applying molecular biology to bioremediation”. Nature Reviews. Microbiology. 1 (1): 35–44. doi:10.1038/nrmicro731. PMID 15040178.
Brim H, McFarlan SC, Fredrickson JK, Minton KW, Zhai M, Wackett LP, Daly MJ (2000). “Engineering Deinococcus radiodurans for metal remediation in radioactive mixed waste environments”. Nature Biotechnology 18 (1): 85–90. doi:10.1038/71986. PMID 10625398.
Author’s Bio
I have completed my Ph.D in agriculture with soil science and agricultural chemistry as specialization. I have done my Ph.D work under the topic – Studies on the development of Green gram (Vigna radiate(L) wilkzek) Rhizobium technology for Terai region of West Bengal. I am interested for some research oriented work under the field in near future.
Dr. Saurabhi (Dhar) Dasgupta
