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 Page 1


UNIT IV
Bioremediation
Chapter 11: Bioremediation
Chapter 11_Bioremediation new correction.indd   253 23-01-2025   11:28:21
Reprint 2025-26
Page 2


UNIT IV
Bioremediation
Chapter 11: Bioremediation
Chapter 11_Bioremediation new correction.indd   253 23-01-2025   11:28:21
Reprint 2025-26
Ananda M. Chakrabarty is an Indian American microbiologist, who 
is known for his work in developing genetically engineered organisms 
using plasmid transfer. In 1965, he earned his Ph.D. from the University 
of Calcutta and moved to the University of Illinois in United States for 
higher studies. He started to work with environmental microbiology 
with an aim to develop microbes for biodegradation. He speci??cally 
worked with Pseudomonas sp. and in 1971, developed a genetically 
engineered Pseudomonas strain that was capable of using oil as 
nutrient for its growth. He called these microbes as “multi-plasmid 
hydrocarbon-degrading Pseudomonas”, which could digest most of the 
hydrocarbons found in oil spills. He was the ??rst to get a patent for a 
recombinant microbe. Patenting living organisms was not available at 
that time and his efforts to patent a recombinant microbe landed in the 
Supreme Court in 1980. This famous trial “Diamond v. Chakrabarty” 
made it possible to patent microbes or higher organisms. Later, his 
research group has done pioneer work with cupredoxin (proteins) from 
Pseudomonas and its role for cancer biology.
 Prof. Chakrabarty served as an expert on legal issues related 
to patents or intellectual property rights. In 2007, Indian government 
recognised his efforts and he was awarded with the Padma Shri.
Ananda Mohan Chakrabarty 
(4 April 1938 – 10 July 2020 )
Chapter 11_Bioremediation new correction.indd   254 23-01-2025   11:28:21
Reprint 2025-26
Page 3


UNIT IV
Bioremediation
Chapter 11: Bioremediation
Chapter 11_Bioremediation new correction.indd   253 23-01-2025   11:28:21
Reprint 2025-26
Ananda M. Chakrabarty is an Indian American microbiologist, who 
is known for his work in developing genetically engineered organisms 
using plasmid transfer. In 1965, he earned his Ph.D. from the University 
of Calcutta and moved to the University of Illinois in United States for 
higher studies. He started to work with environmental microbiology 
with an aim to develop microbes for biodegradation. He speci??cally 
worked with Pseudomonas sp. and in 1971, developed a genetically 
engineered Pseudomonas strain that was capable of using oil as 
nutrient for its growth. He called these microbes as “multi-plasmid 
hydrocarbon-degrading Pseudomonas”, which could digest most of the 
hydrocarbons found in oil spills. He was the ??rst to get a patent for a 
recombinant microbe. Patenting living organisms was not available at 
that time and his efforts to patent a recombinant microbe landed in the 
Supreme Court in 1980. This famous trial “Diamond v. Chakrabarty” 
made it possible to patent microbes or higher organisms. Later, his 
research group has done pioneer work with cupredoxin (proteins) from 
Pseudomonas and its role for cancer biology.
 Prof. Chakrabarty served as an expert on legal issues related 
to patents or intellectual property rights. In 2007, Indian government 
recognised his efforts and he was awarded with the Padma Shri.
Ananda Mohan Chakrabarty 
(4 April 1938 – 10 July 2020 )
Chapter 11_Bioremediation new correction.indd   254 23-01-2025   11:28:21
Reprint 2025-26
Human activities at domestic, agricultural and industrial 
level have resulted in the entry of a large number of 
pollutants in air, water and soil resulting in an alarming 
situation in many areas across the world. Many of these 
untreated chemical toxicants and excess of fertilisers and 
pesticides used in agriculture are drained to various water 
bodies and poses threat to the ecosystem and its ??ora and 
fauna including human beings. It is very much desirable 
that such pollutants must be eliminated from the ecosystem. 
Recently, a good number of microorganisms have been 
reported to be capable of modifying and degrading such 
synthetic agrochemicals. In this chapter, we will discuss  
the management of wastes and pollutants by conventional 
approach as well as by using microorganisms and plants. 
Since living organisms (bios) are employed to remediate or 
solve the problem of damage caused by chemical toxicants, 
the process is often referred to as bioremediation.
11.1 Waste Water t reatment Waste water from a home, community or industry is 
collectively called sewage. Such wastes are very dif??cult 
11.1 Wastewater 
Treatment 
11.2 Solid Waste 
Management 
11.3 Management and 
Disposal of Bio-
medical Waste
11.4 Bioremediation of 
Pesticides
Bioremediation
11
Chapter 
Chapter 11_Bioremediation new correction.indd   255 23-01-2025   11:28:21
Reprint 2025-26
Page 4


UNIT IV
Bioremediation
Chapter 11: Bioremediation
Chapter 11_Bioremediation new correction.indd   253 23-01-2025   11:28:21
Reprint 2025-26
Ananda M. Chakrabarty is an Indian American microbiologist, who 
is known for his work in developing genetically engineered organisms 
using plasmid transfer. In 1965, he earned his Ph.D. from the University 
of Calcutta and moved to the University of Illinois in United States for 
higher studies. He started to work with environmental microbiology 
with an aim to develop microbes for biodegradation. He speci??cally 
worked with Pseudomonas sp. and in 1971, developed a genetically 
engineered Pseudomonas strain that was capable of using oil as 
nutrient for its growth. He called these microbes as “multi-plasmid 
hydrocarbon-degrading Pseudomonas”, which could digest most of the 
hydrocarbons found in oil spills. He was the ??rst to get a patent for a 
recombinant microbe. Patenting living organisms was not available at 
that time and his efforts to patent a recombinant microbe landed in the 
Supreme Court in 1980. This famous trial “Diamond v. Chakrabarty” 
made it possible to patent microbes or higher organisms. Later, his 
research group has done pioneer work with cupredoxin (proteins) from 
Pseudomonas and its role for cancer biology.
 Prof. Chakrabarty served as an expert on legal issues related 
to patents or intellectual property rights. In 2007, Indian government 
recognised his efforts and he was awarded with the Padma Shri.
Ananda Mohan Chakrabarty 
(4 April 1938 – 10 July 2020 )
Chapter 11_Bioremediation new correction.indd   254 23-01-2025   11:28:21
Reprint 2025-26
Human activities at domestic, agricultural and industrial 
level have resulted in the entry of a large number of 
pollutants in air, water and soil resulting in an alarming 
situation in many areas across the world. Many of these 
untreated chemical toxicants and excess of fertilisers and 
pesticides used in agriculture are drained to various water 
bodies and poses threat to the ecosystem and its ??ora and 
fauna including human beings. It is very much desirable 
that such pollutants must be eliminated from the ecosystem. 
Recently, a good number of microorganisms have been 
reported to be capable of modifying and degrading such 
synthetic agrochemicals. In this chapter, we will discuss  
the management of wastes and pollutants by conventional 
approach as well as by using microorganisms and plants. 
Since living organisms (bios) are employed to remediate or 
solve the problem of damage caused by chemical toxicants, 
the process is often referred to as bioremediation.
11.1 Waste Water t reatment Waste water from a home, community or industry is 
collectively called sewage. Such wastes are very dif??cult 
11.1 Wastewater 
Treatment 
11.2 Solid Waste 
Management 
11.3 Management and 
Disposal of Bio-
medical Waste
11.4 Bioremediation of 
Pesticides
Bioremediation
11
Chapter 
Chapter 11_Bioremediation new correction.indd   255 23-01-2025   11:28:21
Reprint 2025-26
Biotechnology XII 256
to treat due to the presence of antiseptic, chemicals and 
its high oxygen demand. Almost all the industries (dairy, 
tannery, cannery, distillery, oil re??nery, textile, coal and 
coke, synthetic rubber, steel, etc.) produce their own 
characteristic sewage. Some are readily treated while 
others are practically unamendable through biological 
treatment. An average individual in India produces 0.8 kg 
waste per day.
11.1.1 Composition of Sewage
Sewage consists of human excreta, wash waters, industrial 
waste, agricultural wastes and wastes from livestock, i.e., 
poultry, cattle, horse, etc. The bulk municipal sewage 
consists of approximately 99 percent water and 1% 
inorganic and organic matter in suspended and soluble 
forms. Lignocellulose, cellulose, proteins, fats and various 
inorganic particulate matter exist in suspended state, 
whereas sugars, fatty acids, alcohols, amino acids and 
inorganic ions constitute the soluble forms. The organic 
content of sewage is measured in terms of its oxygen 
equivalence by means of the biochemical or biological 
oxygen demand (BOD) test. BOD may be de??ned as the 
quantity of oxygen required during the stabilisation of 
Table 11.1: Composition of untreated and treated domestic sewage
Constituent Concentration (mg/L) 
before treatment
Concentration (mg/L) 
after treatment
Suspended Solids (SS) 100–750 Upto 35
Total Nitrogen 20–80 Upto 15
Total Phosphorus 05–20 Upto 5
Chlorides 230–2700 <250
Grease and oil 50–100 <10
Biochemical oxygen demand (BOD) 100–300 Upto 25
Chemical oxygen demand (COD) 600–900 75–100
pH 05–7.5 6.5–8.5
Total coliform 10
7
–10
9
Not detectable
Chapter 11_Bioremediation new correction.indd   256 23-01-2025   11:28:21
Reprint 2025-26
Page 5


UNIT IV
Bioremediation
Chapter 11: Bioremediation
Chapter 11_Bioremediation new correction.indd   253 23-01-2025   11:28:21
Reprint 2025-26
Ananda M. Chakrabarty is an Indian American microbiologist, who 
is known for his work in developing genetically engineered organisms 
using plasmid transfer. In 1965, he earned his Ph.D. from the University 
of Calcutta and moved to the University of Illinois in United States for 
higher studies. He started to work with environmental microbiology 
with an aim to develop microbes for biodegradation. He speci??cally 
worked with Pseudomonas sp. and in 1971, developed a genetically 
engineered Pseudomonas strain that was capable of using oil as 
nutrient for its growth. He called these microbes as “multi-plasmid 
hydrocarbon-degrading Pseudomonas”, which could digest most of the 
hydrocarbons found in oil spills. He was the ??rst to get a patent for a 
recombinant microbe. Patenting living organisms was not available at 
that time and his efforts to patent a recombinant microbe landed in the 
Supreme Court in 1980. This famous trial “Diamond v. Chakrabarty” 
made it possible to patent microbes or higher organisms. Later, his 
research group has done pioneer work with cupredoxin (proteins) from 
Pseudomonas and its role for cancer biology.
 Prof. Chakrabarty served as an expert on legal issues related 
to patents or intellectual property rights. In 2007, Indian government 
recognised his efforts and he was awarded with the Padma Shri.
Ananda Mohan Chakrabarty 
(4 April 1938 – 10 July 2020 )
Chapter 11_Bioremediation new correction.indd   254 23-01-2025   11:28:21
Reprint 2025-26
Human activities at domestic, agricultural and industrial 
level have resulted in the entry of a large number of 
pollutants in air, water and soil resulting in an alarming 
situation in many areas across the world. Many of these 
untreated chemical toxicants and excess of fertilisers and 
pesticides used in agriculture are drained to various water 
bodies and poses threat to the ecosystem and its ??ora and 
fauna including human beings. It is very much desirable 
that such pollutants must be eliminated from the ecosystem. 
Recently, a good number of microorganisms have been 
reported to be capable of modifying and degrading such 
synthetic agrochemicals. In this chapter, we will discuss  
the management of wastes and pollutants by conventional 
approach as well as by using microorganisms and plants. 
Since living organisms (bios) are employed to remediate or 
solve the problem of damage caused by chemical toxicants, 
the process is often referred to as bioremediation.
11.1 Waste Water t reatment Waste water from a home, community or industry is 
collectively called sewage. Such wastes are very dif??cult 
11.1 Wastewater 
Treatment 
11.2 Solid Waste 
Management 
11.3 Management and 
Disposal of Bio-
medical Waste
11.4 Bioremediation of 
Pesticides
Bioremediation
11
Chapter 
Chapter 11_Bioremediation new correction.indd   255 23-01-2025   11:28:21
Reprint 2025-26
Biotechnology XII 256
to treat due to the presence of antiseptic, chemicals and 
its high oxygen demand. Almost all the industries (dairy, 
tannery, cannery, distillery, oil re??nery, textile, coal and 
coke, synthetic rubber, steel, etc.) produce their own 
characteristic sewage. Some are readily treated while 
others are practically unamendable through biological 
treatment. An average individual in India produces 0.8 kg 
waste per day.
11.1.1 Composition of Sewage
Sewage consists of human excreta, wash waters, industrial 
waste, agricultural wastes and wastes from livestock, i.e., 
poultry, cattle, horse, etc. The bulk municipal sewage 
consists of approximately 99 percent water and 1% 
inorganic and organic matter in suspended and soluble 
forms. Lignocellulose, cellulose, proteins, fats and various 
inorganic particulate matter exist in suspended state, 
whereas sugars, fatty acids, alcohols, amino acids and 
inorganic ions constitute the soluble forms. The organic 
content of sewage is measured in terms of its oxygen 
equivalence by means of the biochemical or biological 
oxygen demand (BOD) test. BOD may be de??ned as the 
quantity of oxygen required during the stabilisation of 
Table 11.1: Composition of untreated and treated domestic sewage
Constituent Concentration (mg/L) 
before treatment
Concentration (mg/L) 
after treatment
Suspended Solids (SS) 100–750 Upto 35
Total Nitrogen 20–80 Upto 15
Total Phosphorus 05–20 Upto 5
Chlorides 230–2700 <250
Grease and oil 50–100 <10
Biochemical oxygen demand (BOD) 100–300 Upto 25
Chemical oxygen demand (COD) 600–900 75–100
pH 05–7.5 6.5–8.5
Total coliform 10
7
–10
9
Not detectable
Chapter 11_Bioremediation new correction.indd   256 23-01-2025   11:28:21
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Bioremediation 257
decomposable organic matter and oxidisable inorganic 
matter by aerobic (oxidative) biological action. The 
ef??ciency of mechanical, chemical and biological treatment 
of sewage is based on the amount of BOD reduction. Table 
11.1 shows the composition of an untreated and treated 
domestic sewage.
Box 1: Biochemical Oxygen Demand (BOD)
Biochemical Oxygen Demand is a measure that signi??es the amount of oxygen dissolved in 
water required by different microorganisms present in it. BOD is, in a way, measurement of 
the oxidisable organic matter present in sewage. Higher BOD value signi??es higher amount of 
oxidisable organic matter present and such a sewage is called strong, whereas weak sewage 
has comparatively less oxidisable matter. Entry of strong sewage in a water body leads to a 
quick consumption of dissolved oxygen. Fishes and other aquatic fauna die due to very low 
level of dissolved oxygen, which ultimately decompose and increased level of organic matter 
ultimately makes water unsuitable for recreational purpose and un??t for drinking.
 Measurement of BOD is done by dilution of a measured amount of sewage with water 
already saturated with oxygen followed by incubation of sewage and water mixture at 20°C 
simultaneously with a control, which is diluted water. After ??ve days of incubation, the 
residual oxygen present in both the sewage sample and the control is measured. Difference in 
the level of oxygen is the expression of the capacity to consume oxygen by the sewage, which 
is expressed in parts per million (ppm). However, for the purpose of estimation of BOD of a 
sewage sample (in which the organic load may be too high and dissolved oxygen is too low to be 
measured), the same is diluted with double distilled water. One litre of BOD free water (double 
distilled water) in a bottle is aerated for one hour by an aerator followed by adjusting the pH 
to 7.0 using buffer. BOD is calculated as follows:
BOD (O
2
 mg/L) = 
1 2
D D 100
% dilution
- ×
 or (D
1
 – D
2
) × Dilution factor
D
1
 = Dissolved oxygen (DO) of sample before incubation
D
2
 = Dissolved oxygen (DO) of sample after incubation
Calculation of Dilution factor
S.No. Volume of Sample (mL) Volume of Dilution Water added (mL) Dilution Factor
1 1000 NIL 1
2 500 500 2
3 200 800 5
4 100 900 10
5 50 950 20
6 20 980 50
Chapter 11_Bioremediation new correction.indd   257 23-01-2025   11:28:21
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