29-08-2014, 04:10 PM
BIOREMEDIATION
[attachment=67369]
Introduction
Use of micro-organisms for removal of pollutants from biosphere.
Relies on biological processes to minimize an unwanted environmental pollutant.
Micro-organisms possess ability to degrade, detoxify & even accumulated harmful organic & inorganic compounds
Need & Scope of Bioremediation
Biodegradation refers to a natural process that micro-organism use to breakdown organic compounds into less complex chemicals.
When organic compounds of carbon, nitrogen, sulfur & phosphorus are completely metabolized to inorganic compounds such as: pentachlorophenol is degraded to CO2, H2O & chloride ions
Generally micro-organisms obtain there energy through theses processses
Approaches of Bioremediation
Relies on the ability of micro-organisms to degrade & detoxify organic & inorganic compounds.
Involves natural process to reduce the concentration of the contaminant in an environment, referred as Natural attenuation or intrinsic bioremediation
There are two approaches to enhance Bioremediation
Biostimulation :- depends primarily on the modification of environment.
Bioaugmentation :- which uses the addition of microbial cultures to increase biodegradation.
These two approaches are combined & micro-organisms are introduced in conjunction with such environmental modification as nutrient supplementation
In situ Bioremediation
Degradable processing at the site of pollution such as soil, groundwater
Addition of adequate quantities of nutrients at the site promotes microbial growth.
When micro-organisms are exposed to pollutants, they develop metabolic activities to degrade them.
The growth of micro-organisms & their ability to bring out biodegradation are dependent on the supply of essential nutrients.
Applied for clean-up of : oil spillages, beaches etc
Ex situ Bioremediation
The waste or toxic materials can be collected from the pollutants & the bioremediation with the requisite micro-organisms can be carried out at designed places.
Sequential Degradation
Both aerobic & anaerobic process are involved.
Effective way of reducing toxicity of a pollutant
E.g.: tetrachloromethane & tetrachlroethane
Genetically engineered microbes for Bioremediation
First GEM created was k/a Superbug.
Develpoed by Chakrabarty in 1970.
This bacterium was created from Pseudomonas spp. Possessing different kinds of plasmids for degrading different organic compounds.
Strain possess: plasmid for camphor- octane degradation & naphthalene- xylene degradation
Bioaugmentation
Addition of specific microbes to the polluted soil.
Cocktail or combination of microbes are used.
Pseudomonas strains possess ability to degrade 6-aminohexanoate ( linear dimer, product of nylon) as a source of carbon & nitrogen
Degradation of pesticides & herbicides involve acquisition of such genetic traits
Water Contamination
Petroleum hydrocarbons: most common pollutant of ground water.
Other pollutants: heavy metals, industrial waste, products of incomplete combustion etc.
Bioremediation of ground water involves 2 methods:
pump-treat technique
Biofencing technique
Biofencing technique
Consist of bioactive zone at down edge of contaminated ground water area.
Nutrients are injected to bioactive zone for enhancing microbial growth
Pollutants are degraded & clean ground water comes out.
Microbes used: superbug, Pseudomonas fluorescence(aerobic bacteria) containing plasmid for degradation of naphthalene
Phytoremediation
Use of plants to stabilize, remediate & reduce contamination of soil, sediment & surface as well as ground water.
Phyto: plant & remediation: to correct
It relies on ability of plant to act’s as: solar-driving pumping & filtering system & stimulating the natural tendency of ecosystem to restore itself.
It is attractive remediation technology for removing hazardous substances
[attachment=67369]
Introduction
Use of micro-organisms for removal of pollutants from biosphere.
Relies on biological processes to minimize an unwanted environmental pollutant.
Micro-organisms possess ability to degrade, detoxify & even accumulated harmful organic & inorganic compounds
Need & Scope of Bioremediation
Biodegradation refers to a natural process that micro-organism use to breakdown organic compounds into less complex chemicals.
When organic compounds of carbon, nitrogen, sulfur & phosphorus are completely metabolized to inorganic compounds such as: pentachlorophenol is degraded to CO2, H2O & chloride ions
Generally micro-organisms obtain there energy through theses processses
Approaches of Bioremediation
Relies on the ability of micro-organisms to degrade & detoxify organic & inorganic compounds.
Involves natural process to reduce the concentration of the contaminant in an environment, referred as Natural attenuation or intrinsic bioremediation
There are two approaches to enhance Bioremediation
Biostimulation :- depends primarily on the modification of environment.
Bioaugmentation :- which uses the addition of microbial cultures to increase biodegradation.
These two approaches are combined & micro-organisms are introduced in conjunction with such environmental modification as nutrient supplementation
In situ Bioremediation
Degradable processing at the site of pollution such as soil, groundwater
Addition of adequate quantities of nutrients at the site promotes microbial growth.
When micro-organisms are exposed to pollutants, they develop metabolic activities to degrade them.
The growth of micro-organisms & their ability to bring out biodegradation are dependent on the supply of essential nutrients.
Applied for clean-up of : oil spillages, beaches etc
Ex situ Bioremediation
The waste or toxic materials can be collected from the pollutants & the bioremediation with the requisite micro-organisms can be carried out at designed places.
Sequential Degradation
Both aerobic & anaerobic process are involved.
Effective way of reducing toxicity of a pollutant
E.g.: tetrachloromethane & tetrachlroethane
Genetically engineered microbes for Bioremediation
First GEM created was k/a Superbug.
Develpoed by Chakrabarty in 1970.
This bacterium was created from Pseudomonas spp. Possessing different kinds of plasmids for degrading different organic compounds.
Strain possess: plasmid for camphor- octane degradation & naphthalene- xylene degradation
Bioaugmentation
Addition of specific microbes to the polluted soil.
Cocktail or combination of microbes are used.
Pseudomonas strains possess ability to degrade 6-aminohexanoate ( linear dimer, product of nylon) as a source of carbon & nitrogen
Degradation of pesticides & herbicides involve acquisition of such genetic traits
Water Contamination
Petroleum hydrocarbons: most common pollutant of ground water.
Other pollutants: heavy metals, industrial waste, products of incomplete combustion etc.
Bioremediation of ground water involves 2 methods:
pump-treat technique
Biofencing technique
Biofencing technique
Consist of bioactive zone at down edge of contaminated ground water area.
Nutrients are injected to bioactive zone for enhancing microbial growth
Pollutants are degraded & clean ground water comes out.
Microbes used: superbug, Pseudomonas fluorescence(aerobic bacteria) containing plasmid for degradation of naphthalene
Phytoremediation
Use of plants to stabilize, remediate & reduce contamination of soil, sediment & surface as well as ground water.
Phyto: plant & remediation: to correct
It relies on ability of plant to act’s as: solar-driving pumping & filtering system & stimulating the natural tendency of ecosystem to restore itself.
It is attractive remediation technology for removing hazardous substances