here i have been given the detailed presentation on control of environmental pollution by using biotechnology/biologically, when i was studying Ph.D(Aquaculture) in Mangalore Fisheries College for 2 months!!!!!!
now i am doing Ph.D in Extension Dept. in Kolkata. I had my P.G in Extension only.
4. O These are biophysical devices which can detect
and measure the presence of specific
substances.
O Definition: it is an analytical device containing an
immobilized biological material, which can
interact with an analyte and produce signals to
measure.
O Biosensors basically involve in the quantitative
analysis of various substances by converting
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their biological actions into measurable signals.
5. O Components of biosensor
Biological component
Physical component
O Special kits have been designed to identify the
specific pollutants.
Gas biosensors
Immunoassay biosensors
BOD biosensors
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6.
7. O Definition: it is the process of using
microorganisms to remove the environmental
pollutants.
O Bioremediation is carried out in two ways:
In situ bioremediation
Intrinsic bioremediation
Engineered in situ bioremediation
Ex-situ bioremediation
Solid phase treatment
Slurry phase treatment 7
8. O It is a direct approach for the microbial degradation
of xenobiotics at the site of pollution.
O Generally used for cleanup of oil spillage, etc.
Intrinsic bioremediation:
It is the inherent metabolic ability of the
microorganisms to degrade certain pollutants.
There will be no addition of nutrient supply for
accelerating metabolic activity.
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9. Engineered in situ bioremediation:
Here the bioremediation process is engineered to
increase the degradation efficiency.
In this process optimal environment will be
maintained for the microorganisms to overcome
the slow and limited bioremediation.
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10. O The waste will be collected from the polluted
sites and the bioremediation will be carry out at
designed place by using microorganisms.
O Classification
Solid phase treatment
Slurry phase treatment
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11. O Solid phase treatment:
This system includes land treatment soil piles
comprising of organic wastes.
O Slurry phase treatment:
This is a triphasic treatment system involving
three components (water, suspended
particulate matter and air).
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12. Use of genetic engineering for
efficient bioremediation
O In recent years, efforts have been made to create
genetically engineered microorganisms (GEMs) to
overcome problems and enhance bioremediation.
O Problems during bioremediation are:
Growth of microorganisms reduced by the
xenobiotics.
Natural one type of microorganism can’t degrade all
the xenobiotics.
Slow process.
Sometimes xenobiotics will become unavailable 12
form.
13. O The genetic manipulations of plasmids can lead
to the creation of new strains of bacteria.
O In 1970s new strain of pseudomonas was
developed by the scientists named as
“superbug”.
O This superbug has the capability of degrading
hydrocarbons of petroleum.
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14. Engineered bacteria used for the degradation of
xenobiotics.
Bacterium Substrate that can be degraded
Pseudomonas capacia 2,4,5- trichloro-phenoxy acetic acid
P. putida & other sp. 2,2,5-dichloropropionate; mono and
dichloroaromatics
Alcaligenes sp. Dichlorophenoxyacetic acid, mixed
chlorophenols; 1,4- dichlorobenzene
Acinetobacter sp. 4-chlorobenzene
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15. O Biofertilizer: Nutrient inputs of biological origin to
support plant growth by the addition of microbes.
O Biofertilizers are divided into four categories.
1. Symbiotic nitrogen fixers
2. Asymbiotic nitrogen fixers
3. Phosphate solubilizing bacteria
4. Organic fertilizers
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16. O Symbiotic nitrogen fixers:
The diazotrophic microorganisms are the
symbiotic nitrogen fixers that serve as
biofertilizers e.g. Rhizobium sp.,
Bradyrhizopium sp.
O Asymbiotic nitrogen fixers:
The asymbiotic nitrogen fixing bacteria can
directly convert the gaseous nitrogen to nitrogen
rich compounds. e.g. Azobacter sp.,
Azospirillum sp.
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17. O Phosphate solubilizing bacteria:
Thiobacillus, Bacillus are capable of
converting non-available inorganic phosphorus
present in the soil to organic or inorganic form
of phosphate.
O Organic fertilizers:
Certain types of organic wastes are used
as fertilizers e.g. animal dung, urban garbage,
sewage, crop residues and oil cakes.
All these wastes can be converted in to
organic manures. 17
18. Advantages:
Improves the tolerance against toxic heavy
metals.
Possible to fertile the saline and alkaline
soils.
Helps in environmental pollution control.
Fertility of soil will be increased year after
year.
Low cost and easy to produce.
Increases the physico-chemical properties of
the soil, soil texture and water holding
capacity. 18
19. Global warming, industrialization and increasing
price of fossil fuels made search of alternative.
An alternative, biodegradable, domestic fuel
contributes no net CO2 or S2 to the atmosphere.
Mono alkyl esters of long chain fatty acids
derived from a renewable lipid feed stock such
as vegetable oil or animal fat will be used.
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20. ADVANTAGES:
O Biodegradable
O Non-toxic fuel
O Not contribute to global warming
O Alternative to petro -based fuels
O Favorable energy balance
O Lower harmful emissions of CO2 & unburned
hydrocarbons
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21. O CO2 is the main cause of green house effect.
O There is steady increase in the CO2 content
mainly due to industrial processes.
O Biotechnological methods have been used to
reduce the atmospheric CO2 content at two levels:
Photosynthesis
Biological calcification.
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22. O Fast growing plants utilize CO2 more
efficiently.
O Further, CO2 utilization can be increased by
enhancing the rate of photosynthesis.
O Ribulosebiphosphate carboxylase is an
enzyme which can fix the CO2 efficiently.
O Microalgae like chlorella and spirulina can
utilize CO2 efficiently than higher plants.
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23. O The sewage is treated to get rid of the undesirable
substances by subjecting the organic matter to
biodegradation by microorganisms.
O The biodegradation involves the degradation of
organic matter to smaller molecules and requires
constant supply of oxygen.
O This problem is overcome by growing microalgae in
the ponds and tanks where sewage treatment is
carried out.
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24. Removal of oil by using biotechnology
O Manual and mechanical cleaning is very
expensive.
O To overcome this oleophilic fertilizers are being
developed.
O These fertilizers will allow rapid growth and
multiplication of microorganisms.
O Recently oil utilizing microbes were developed by
using genetic engineering. 24
25. O Some of the oil utilizing microbes can also
produce surface active compounds that can
emulsify oil in water and thereby removing the
oil.
O A strain of Pseudomonas aeruginosa produces
a glycolipid emulsifier that reduces the surface
tension of oil-water interface which helps in the
removal of oil from water.
O This microbial emulsifier is nontoxic and
biodegradable and has shown promising results
in the laboratory experiments.
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26. O Use of chemical pesticides, herbicides and
fertilizers are hazardous.
O They undergo degradation by microorganisms
and ultraviolet light which releases toxic
chemicals.
O To overcome this bacterial and viral pesticides are
being developed by using biotechnology.
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27. O Mutation of the microbes may cause
diseases to the organisms.
O Cost effective and more shelf life biofertilizers
should be developed.
O Micro algae like Chlorella, Spirulina should
be cultured near the industries.
O Protection of coral beds.
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28. O Use of biofertilizers and biofuels should be
encouraged.
O Recycling of the different products
should be increase.
O Organic farming has to be develop.
O Continuous biomonitoring of the environment and
biological control methods should be developed
rather than chemical methods.
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