The document discusses the use of enzymes in bioremediation. It outlines that enzymatic bioremediation uses isolated enzymes to transform contaminants into less toxic compounds. Extracellular enzymes from white rot fungi have been shown to effectively degrade pollutants like PAHs, PCBs, and dyes. Major enzymes used include lignin peroxidase, manganese peroxidase, and laccase. Case studies demonstrate how these enzymes can decolorize over 90% of textile dyes. While enzymatic bioremediation provides advantages over chemical and microbial methods, further research is needed to reduce costs and improve enzyme stability and activity under various conditions.
Hydrocarbon are major constituents of crude oil and petroleum. They can be biodegraded by naturally-occurring microorganisms in freshwater and marine environments under a variety of aerobic and anaerobic conditions. The ability of microorganisms - bacteria, archaea, fungi, or algae - to break down hydrocarbons is the basis for natural and enhanced bioremediation. To promote biodegradation, amendments such as nitrogen and phosphorous fertilizer are often added to stimulate microbial growth and metabolism
“Bioleaching" or "bio-oxidation" employs the use of naturally occurring bacteria, harmless to both humans and the environment, to extract of metals from their ores.
Conversion of insoluble metal sulfides into water-soluble metal sulfates.
It is mainly used to recover certain metals from sulfide ores. This is much cleaner than the traditional leaching.
Hydrocarbon are major constituents of crude oil and petroleum. They can be biodegraded by naturally-occurring microorganisms in freshwater and marine environments under a variety of aerobic and anaerobic conditions. The ability of microorganisms - bacteria, archaea, fungi, or algae - to break down hydrocarbons is the basis for natural and enhanced bioremediation. To promote biodegradation, amendments such as nitrogen and phosphorous fertilizer are often added to stimulate microbial growth and metabolism
“Bioleaching" or "bio-oxidation" employs the use of naturally occurring bacteria, harmless to both humans and the environment, to extract of metals from their ores.
Conversion of insoluble metal sulfides into water-soluble metal sulfates.
It is mainly used to recover certain metals from sulfide ores. This is much cleaner than the traditional leaching.
Environmental Microbiology: Microbial degradation of recalcitrant compoundsTejaswini Petkar
A brief presentation on 'Microbial degradation of recalcitrant compounds'- their classes,their sources, the microorganisms involved and their modes of degradation,
Methanogenesis or biomethanation is the formation of methane by microbes known as methanogens. Organisms capable of producing methane have been identified only from the domain Archaea, a group phylogenetically distinct from both eukaryotes and bacteria, although many live in close association with anaerobic bacteria.
•Introduction of bioremediation: Bioremediation refers to the process of using microorganisms to remove the environmental pollutants i.e. toxic wastes found in soil, water, air etc.
•In situ bioremediation:
It involves a direct approach for the microbial
degradation of xenobiotics at the sites of pollution
(soil, ground water).
•Types of in situ bioremediation:
Natural attenuation.
Engineered in situ bioremediation.
- Bioventing, biosparging, bioslurping,
phytoremediation.
•Ex situ bioremediation:
Waste or toxic pollutants can be collected from the polluted sites and bioremediation can be carried out at a designated place or site.
• Types of ex situ bioremediation
Land farming, windrow, biopiles, bioreactors.
•Microorganisms use in bioremediation:
A number of naturally occurring marine microbes
such as Pseudomonas sp. is capable of degrading oil and other hydrocarbons.
•Factors affecting bioremediation:
Nutrient availability, moisture content, pH, temperature, contaminant availability.
•References:
Satyanarayana U. Biotechnology. BOOKS AND ALLIED (P) Ltd.
Sharma P.D. Environmental Microbiology. RASTOGI PUBLICATIONS.
Gupta P.K. Biotechnology and Genomics. RASTOGI PUBLICATIONS.
Dubey R.C. A Textbook of Biotechnology. S Chand And Company Ltd.
Dubey R.C. A Textbook of Microbiology. S Chand And Company Ltd.
Willey/Sherwood/Woolverton. Prescott’s Microbiology. McGRAW-HILL INTERNATIONAL EDITION.
www.sciencedirect.com/bioremediation.
"Remediate" means to solve a problem, and "bio-remediate" means to use biological organisms to solve an environmental problem such as contaminated soil or groundwater.
Bioremediation means to use a biological remedy to abate or clean up contamination.
According to the EPA, bioremediation is a “treatment that uses naturally occurring organisms to break down hazardous substances into less toxic or non toxic substances”.
Introduction
Type of pesticides
Advantage & disadvantages of pesticides
Degradation of pesticide
Microbial degradation of pesticides
Mode of microbial metabolism of pesticides
Strategies for biodegradation
Approaches for biodegradation of pesticide
Chemical reaction leading biodegradation of pesticide
Metabolism of pesticides by MO
Metabolism of DDT
Lignocelluloses, the major component of biomass, makes up about half of the matter produced by photosynthesis. It consists of three types of polymers – cellulose, hemicellulose, and lignin – that are strongly intermeshed and chemically bonded by non-covalent forces and by covalent cross-linkages. A great variety of fungi and bacteria can fragment these macromolecules by using a battery of hydrolytic or oxidative enzymes. In native substrates, binding of the polymers hinders their biodegradation. Molecular genetics of cellulose-, hemicellulose- and lignin-degrading systems advanced considerably during the 1990s. Most of the enzymes have been cloned, sequenced, and expressed both in homologous and in heterologous hosts. Much is known about the structure, genomic organization, and regulation of the genes encoding these proteins.
Basic Knowledge about industrial microorganism. why industry choose microorganism rather than chemical. isolation technique of microorganism. source of microorganisms. Process of using microorganism. Disadvantages of using microorganisms in industry. Process of genetic modification of microorganisms. Storage process of microorganism. preservation methods of microorganism. Reculture methods of microorganism.
Environmental Microbiology: Microbial degradation of recalcitrant compoundsTejaswini Petkar
A brief presentation on 'Microbial degradation of recalcitrant compounds'- their classes,their sources, the microorganisms involved and their modes of degradation,
Methanogenesis or biomethanation is the formation of methane by microbes known as methanogens. Organisms capable of producing methane have been identified only from the domain Archaea, a group phylogenetically distinct from both eukaryotes and bacteria, although many live in close association with anaerobic bacteria.
•Introduction of bioremediation: Bioremediation refers to the process of using microorganisms to remove the environmental pollutants i.e. toxic wastes found in soil, water, air etc.
•In situ bioremediation:
It involves a direct approach for the microbial
degradation of xenobiotics at the sites of pollution
(soil, ground water).
•Types of in situ bioremediation:
Natural attenuation.
Engineered in situ bioremediation.
- Bioventing, biosparging, bioslurping,
phytoremediation.
•Ex situ bioremediation:
Waste or toxic pollutants can be collected from the polluted sites and bioremediation can be carried out at a designated place or site.
• Types of ex situ bioremediation
Land farming, windrow, biopiles, bioreactors.
•Microorganisms use in bioremediation:
A number of naturally occurring marine microbes
such as Pseudomonas sp. is capable of degrading oil and other hydrocarbons.
•Factors affecting bioremediation:
Nutrient availability, moisture content, pH, temperature, contaminant availability.
•References:
Satyanarayana U. Biotechnology. BOOKS AND ALLIED (P) Ltd.
Sharma P.D. Environmental Microbiology. RASTOGI PUBLICATIONS.
Gupta P.K. Biotechnology and Genomics. RASTOGI PUBLICATIONS.
Dubey R.C. A Textbook of Biotechnology. S Chand And Company Ltd.
Dubey R.C. A Textbook of Microbiology. S Chand And Company Ltd.
Willey/Sherwood/Woolverton. Prescott’s Microbiology. McGRAW-HILL INTERNATIONAL EDITION.
www.sciencedirect.com/bioremediation.
"Remediate" means to solve a problem, and "bio-remediate" means to use biological organisms to solve an environmental problem such as contaminated soil or groundwater.
Bioremediation means to use a biological remedy to abate or clean up contamination.
According to the EPA, bioremediation is a “treatment that uses naturally occurring organisms to break down hazardous substances into less toxic or non toxic substances”.
Introduction
Type of pesticides
Advantage & disadvantages of pesticides
Degradation of pesticide
Microbial degradation of pesticides
Mode of microbial metabolism of pesticides
Strategies for biodegradation
Approaches for biodegradation of pesticide
Chemical reaction leading biodegradation of pesticide
Metabolism of pesticides by MO
Metabolism of DDT
Lignocelluloses, the major component of biomass, makes up about half of the matter produced by photosynthesis. It consists of three types of polymers – cellulose, hemicellulose, and lignin – that are strongly intermeshed and chemically bonded by non-covalent forces and by covalent cross-linkages. A great variety of fungi and bacteria can fragment these macromolecules by using a battery of hydrolytic or oxidative enzymes. In native substrates, binding of the polymers hinders their biodegradation. Molecular genetics of cellulose-, hemicellulose- and lignin-degrading systems advanced considerably during the 1990s. Most of the enzymes have been cloned, sequenced, and expressed both in homologous and in heterologous hosts. Much is known about the structure, genomic organization, and regulation of the genes encoding these proteins.
Basic Knowledge about industrial microorganism. why industry choose microorganism rather than chemical. isolation technique of microorganism. source of microorganisms. Process of using microorganism. Disadvantages of using microorganisms in industry. Process of genetic modification of microorganisms. Storage process of microorganism. preservation methods of microorganism. Reculture methods of microorganism.
file ppt enzim protease, enzim yang berfungsi pada substrat protein dengan mengkatalisis reaksi hidrolisis molekul protein pada ikatan peptidanya menjadi asam amino2 yang lebih sederhana.
PHYTOREMEDIATION - Using Plants To Clean Up Our Environment - By HaseebHaseeb Gerraddict
Phytoremediation is the direct use of green plants and their associated microorganisms to stabilize or reduce contamination in soils, sludges, sediments, surface water, or ground water.
The following presentation is only for quick reference. I would advise you to read the theoretical aspects of the respective topic and then use this presentation for your last minute revision. I hope it helps you..!!
Mayur D. Chauhan
Vitamin B12- Chemistry, functions and clinical significanceNamrata Chhabra
Vitamin B12- Chemical structure, Forms of B12, Sources, absorption, storage, transportation, metabolic role, deficiency, megaloblastic anemia and neurological changes, laboratory diagnosis and treatment
Chemical conversion of a substance mediated by living organisms or enzymes
Can result in DETOXIFICATION and BIOACTIVATION
Vital to survive
Key in defense mechanism
The IOSR Journal of Pharmacy (IOSRPHR) is an open access online & offline peer reviewed international journal, which publishes innovative research papers, reviews, mini-reviews, short communications and notes dealing with Pharmaceutical Sciences( Pharmaceutical Technology, Pharmaceutics, Biopharmaceutics, Pharmacokinetics, Pharmaceutical/Medicinal Chemistry, Computational Chemistry and Molecular Drug Design, Pharmacognosy & Phytochemistry, Pharmacology, Pharmaceutical Analysis, Pharmacy Practice, Clinical and Hospital Pharmacy, Cell Biology, Genomics and Proteomics, Pharmacogenomics, Bioinformatics and Biotechnology of Pharmaceutical Interest........more details on Aim & Scope).
All manuscripts are subject to rapid peer review. Those of high quality (not previously published and not under consideration for publication in another journal) will be published without delay.
The answers to these questions are covered both in the lecture materi.pdffunkybabyindia
The answers to these questions are covered both in the lecture material and the text book What
reaction, oxidation or reduction, is key to uranium bioremediation? How does the role of energy
production lead to the action of bioremediation by microorganisms? What are xenobiotics and
what are some examples? What is the role of microbes in the bioremediation of xenobiotics?
Explain how the bioremediation of the herbicide 2, 4, 5-1 shown below, produces energy lord
microbes.
Solution
1. Bioremediation is a process which involves the use of microorganisms to remove or
neutralize from contaminants, such as polluted soil or water. In the absence of oxygen, bacteria
are able to respire various electron acceptors for the energy required for its metabolism. At the
environmentally neutral pH, the aquaous U has a similar redox couple to Fe(III), therefore
Fe(III)-reducing bacteria are able to respire aquaous U as an alternative electron acceptor,
reducig it to insoluble U. Reduction of Uranium is the key reaction for the bioremediation of
uranium, For the bioremediation of Uranium the process is stimulated by adding electron donor
such as acetate, lactate or ethanol from which electrons can be taken up by bacteria to gain the
energy to promote the enzymatic (microbial) reduction of aquaous U to insoluble U in anaerobic
condition. The end product of this process would be uraninite. 3. Xenobiotics are the synthetic
compounds found in living organisms, which are not produced by and foreign to that organisms.
They are also synthetic substances (doesn\'t produced naturally) which are found in higher
concentration than its normal level in the entire biological system. Examples of xenobiotics are:
Halocarbons: consist of halogen group in their structure and used in solvents, pesticides,
propellents etc. Due to their volatile nature, they often escape and destruct the ozone layer.
Synthetic polymers: mainly used to form polyester, polyvinyl chloride etc Carcinogen, food
additives, drugs are also examples of the xenobiotics. Normally the degradation of xenobiotics
by microorganisms is very rare, as the availability of the xenobiotics to the microorganisms is
very low as compared to its concentration in environment. However, when certain microbes are
exposed to these xenobiotics continuously, they develop the ability to degrade the compounds.
Mutations in microbes occur in such a way so that its active site can shows increased affinity
towards the xenobiotics and some mutates to form new enzymatic pathway for degradation of
xenobiotics. Use of mixed population is very effective for bioremediation of xenobiotics. It
creates the cometabolism process n their combined effect is higher than the individual alone.
Genetic engineering can also be used to modify microbes for degrading xenobiotics. 4. The
microbes while degrading herbicide 2,4,5-T, it produces an end product named succinate +
acetate. Succinate is the intermediate of the TCA (TriCarboxylicAcid) cycle, so it.
BOTECHNOLOGY IS CHALLENGING SUBJECT TO TEACH AND UNDERSTAND ALSO .....THEIR INTERESTING PART IS TO LEARN ABOUT MICROBIAL BIO TRANSFORMATION WITH BIOCHEMICAL REACTIONS
It is probably not unscientific to suggest that somewhere or other some
microorganism exists which can, under suitable conditions, oxidize
any substances which is theoretically capable of being oxidized.
E.F. Gale, The Chemical Activities of Bacteria (1952)
Isolation and Screening of Hydrogen Producing Bacterial Strain from Sugarcane...Editor IJCATR
The aim of this study is to isolate a highly competent bacterium with potent cellulose degrading capability and a better
hydrogen producer. Soil sample from sugarcane bagasse yard was isolated, serially diluted and plated on cellulose specific nutrient
agar plate. Four colonies have been isolated in which a single colony has potent cellulose degrading ability and the highest hydrogen
productivity of 275.13 mL H2 L-1. The newly isolated bacterium was morphologically and biochemically characterized. The
molecular characterization of the bacterium was carried out using 16S rDNA sequencing and the organism was identified as
Bacilllus subtilis AuChE413. Proteomic analysis such as MALDI-TOF was carried out to differentiate the isolated Bacillus subtilis
from Bacillus thuringiensis and Bacillus amyloliquefaciens. Phylogenetic tree was constructed to analyze the evolutionary
relationship among different genus and species with the newly isolated strain.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
The Art Pastor's Guide to Sabbath | Steve ThomasonSteve Thomason
What is the purpose of the Sabbath Law in the Torah. It is interesting to compare how the context of the law shifts from Exodus to Deuteronomy. Who gets to rest, and why?
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
1. USE OF ENZYMES IN BIOREMEDIATION
BACHELOR OF TECHNOLOGY (BIOTECHNOLOGY)
BY
SNEHAL.S.MENON
1
DEPARTMENT OF BIOTECHNOLOGY,
STES’S SINHGAD COLLEGE OF ENGINEERING,
VADGAON (BK), OFF SINHGAD ROAD,
PUNE- 411041
2. OUTLINE
Introduction
Bioremediation
Enymatic bioremediation
Enzymological background
Extracellular enzymes used in bioremediation
Advantages and disadvantages of extracellular enzymes
Soluble and immobilized enzymes
Plants and their associated enzymes in bioremediation
Major enzymes used in bioremediation
Case studies
Scope of enzymatic bioremediation and future prospects
Conclusion
References
2
4. TYPES OF POLLUTION
Atmospheric
pollution:
pollution of air.
Water
pollution:
pollution of hydrosphere or water.
Industrial
effluents pollution:
pollution due to disposal of waste water.
Domestic
effluent pollution:
pollution due to indiscriminate dispersal of domestic sewage.
Soil
pollution:
pollution of lithosphere or land.
4
5. OTHER TYPES OF POLLUTION
Noise pollution
Vibration
Noxious odours
5
6. BIOREMEDIATION:
According to E.K. Nyer, the term “bioremediation” refers to all biochemical
reactions of natural attenuation, which includes all biotic and abiotic
processes used to reduce contaminant levels.
Biodegradation is the primary mechanism to reduce biodegradable
contaminants by employing organisms like bacteria, fungi, algae or plants.
Figure 1: The process of waste bioremediation
6
.
7. TYPES OF BIOREMEDIATION
Microbial
bioremediation:
Bioremediation can occur either naturally, or
by the use of bioaugmentation (whole cell introduction) or
Biostimulation approaches (use of nutrients or conditions to stimulate the
native microbial community).
Enzymatic
bioremediation:
Isolated enzymes may also be used to transform the contaminant into lesstoxic or non-toxic compounds.
Extracellular enzymes:
Extracellular enzymes are either secreted from organisms such as white rot
fungi or are produced during a fermentation process.
Phytoremediation:
It is the in situ use of plants, their enzymatic system, their roots and
associated microorganisms to degrade harmless pollutants present in different
7
environmental systems (soil, sediments, groundwater and air).
8. ENZYMATIC BIOREMEDIATION:
Enzymological background:
Enzymes are biological catalysts that facilitate the conversion of substrates
into products by providing favourable conditions that lower the activation
energy of the reaction.
The regions of the enzyme that are directly involved in the catalytic process
are called the active sites.
8
Figure 2: Mechanism of enzymes
9. EXTRACELLULAR ENZYMES IN BIOREMEDIATION:
Extracellular enzymes refer to those enzymes that are either secreted by the
microbes, such as white rot fungi or those that enter the aqueous phase
during an aerobic submerged fermentation process.
Such enzymes are naturally produced by the microbes and then harvested.
Enzymes from white rot fungi have been shown to be effective
degraders of TNT, phenols, PCBs, PAHs and dyes.
Chrysene(PAHs)
Lindane(pesticide)
Polychlorinated
biphenyls(PCBs)
Figure 3: Some xenobiotics amenable to enzymatic bioremediation
9
10. ADVANTAGES AND DISADVANTAGES OF EXTRACELLULAR
ENZYMES
ADVANTAGES
DISADVANTAGES
• Can work in multiple
environments.
• Can be recovered and
recycled.
• Can be used with
different substrates.
• They are biodegradable.
• Difficult
to
maintain
enzyme concentration.
• Difficult to optimize.
• Limits overall success.
• High cost.
10
11. SOLUBLE AND IMMOBILIZED ENZYMES
Soluble enzymes
Mobile enzymes can be added at a single point and then spread due to
diffusion, dispersion. and the flows of groundwater and surface water .
Immobilized enzymes
Enzymes can he immobilized onto
granular, fibrous, a tube or a membrane.
a
carrier,
which
can
be
Figure 4: Types of immobilization of enzymes
In general, immobilization makes the enzyme more resistant to
11
temperature, pH and substrate concentration swings, giving it a longer
lifetime and higher productivity per active unit.
12. PLANTS AND THEIR ASSOCIATED ENZYMES IN BIOREMEDIATION
The involvement of plants in the bioremediation of pollutants is called as
phytoremediation.
The process of phytoremediation is an emerging green technology that
facilitates the removal or degradation of the toxic chemicals in soils,
sediments, groundwater, surface water and air.
Figure 5: Enzymatic and microbial activities responsible
for enhanced remediation in rhizospheric zone
12
13. MAJOR ENZYMES USED IN BIOREMEDIATION
Enzymes from white rot fungi have been found to be very capable of
degrading a large number of different contaminants.
White rot fungi are unique among eukaryotes because they are able to
cleave the carbon-carbon bonds in contaminants such as PAHs.
During the secondary metabolism of plant life, white rot fungi produce and
secrete LiP, manganese peroxidase (MnP) and laccase.
Each of the enzymes can catalyze the one-electron oxidation of phenols and
non-phenolitic substrates.
This results in the production of cation-radical intermediates, which can be
used to futher oxidize non-phenolitic substrates.
13
14.
Lignin peroxidase(LiP)
LiPs are hemoproteins which catalyze reactions in the presence of hydrogen
peroxide.
LiP is very effective in the bioremediation of PAHs.
LiP from Phanerochete chrysosporium. for example. is able to degrade
PAHs.
LiP is also capable of degrading benzo[a]pyrene into 52% 1,6-quinone, 25%
3,6-quinone. and 23% 6,12-quinone.
These product ratios are very similar to those found from the degradation of
benzo[a]pyrene using chemical and electrochemical means.
Benzo[a]pyrene(PAHs)
14
15.
Manganese peroxidase (MnP):
MnP is also a hydrogen peroxide dependent enzyme,but it can only oxidize
organics when in the presence of Mn(Il).
MnP oxidizes Mn(II) to Mn(III), which acts as an obligatory oxidation
intermediate for the oxidation of various compounds.
The Mn(IlI) ions migrate away from the enzyme and start the oxidation of the
lignin and other compounds.
15
Figure 6: Mechanism of MnP
16.
Laccase:
Laccases are multi-copper oxidases that catalyze the one electron oxidation
of substituted phenols, anilines, and aromatic thiols to the corresponding
radicals with the concomitant reduction of molecular oxygen to water.
These radicals produce polymeric products by self-coupling or crosscoupling with other molecules, and dechlorination, demethoxylation and
decarboxylation during coupling and polymerization of differently
substituted substrates may also occur.
These enzymes appear suitable and versatile catalysts, very useful for the
application in several biotechnological processes.
16
Figure 7: Designer laccases
17. OTHER EXTRACELLULAR ENZYMES USED IN BIOREMEDIATION
HRP is a peroxidase that is secreted by the root hairs of the horseradish
plant and can catalyze the oxidation of compounds such as phenols,
biphenols, anilines and benzidines over a large range of pHs and
temperatures .
Extracellular enzymes such as proteases, amylases and lipases are produced
during the aerobic fermentation of organic matter by yeast or other
microbes.
Environments such as waste-water require a different type of enzyme and
these enzymes, rather than catalyzing the oxidation of recalcitrant
compounds, catalyze the degradation of organic matter .
17
18. CASE STUDIES
BIOREMEDIATION OF TEXTILE EFFLUENT USING ENZYMES
Enzymes can act on specific recalcitrant pollutants to remove them by
precipitation or transformation to other products.
White-rot fungi were able to degrade dyes using lignin peroxidase (LiP)
and manganese dependent peroxidase (MnP)
The manganese peroxidase produced by Phanerochaete sordida showed
higher range of 90% decolorization of azo and anthraquinone dye.
The comparison of the fungal isolates and enzymatic treatment in the
degradation of reactive blue 5 dyes was carried out and the degrading
capacity of the enzyme manganese peroxidase was 1.5 times greater than
the fungal isolates.
Lignin peroxidase obtained from Phanerochaete chrysosporium is effective
against methylene blue and azure B dyes
VP (Versatile peroxidase) has been recently described as new family of
ligninolytic peroxidases,together with lignin peroxidase and manganese
18
peroxidase obtained from Phanerochaete chrysosporium .
19.
These enzymes exhibited both lignolytic peroxidase and manganese
peroxidase activity and therefore these enzymes were called as hybrid
manganese peroxidase-lignin peroxidase or versatile peroxidase.
Recalcitrant dyes could be successfully decolorized by peroxidases in the
presence of some suitable redox mediators.
Treatment of recalcitrant pollutants by using enzyme-redox mediator system
will be significantly useful procedure for targeting number of dyes with
diversified structures.
Laccase produced by Pycnoporus snnguineus in liquid cultures can
completely decolor bromophenol blue and malachite green (both
triphenylmethane dyes) and partially decolor orange G and amaranth (both
azo dyes).
lmmobilization of the enzyme on alumina increased its thermal stability and
made it less affected by inhibitors, such as halides and dye additives.
lmmobilized laccase was also able to decrease the toxicity of the dyes by up
to 80%
19
20.
The enzymatic decolorization of industrial dyes is a big challenge due to
large diversity of chemical structures.
Enzymes offered several advantages such as greater specificity, better
standardization, easy handle and store and no dependence on bacterial growth
rates.
A major obstacle that will have to he overcome is the long contact time
required for decolorization to occur.
20
21. SCOPE OF ENZYMATIC BIOREMEDIATION AND
FUTURE PROSPECTS
The scope of bioremediation is to decrease the concentration of organic
pollutants at undetectable levels or, if measurable, lower than the limits
established as safe or tolerable by regulatory agencies.
There are several fields in which enzymes can be applied:
Figure 8: Overview of enzymology of biological remediation
Enzymatic bioremediation improved with molecular tools can be
particularly suitable for situations where rapid remediation is required.
21
22. CONCLUSION
Enzymes present environmental advantages against chemicals and
microorganisms. They are:the biotransformation does not generate toxic side products as is often the
case with chemical and some microbiological processes;
the enzymes are digested, in situ, by the indigenous microorganisms after the
treatment;
the requirement to enhance bio-availability by the introduction of organic
co-solvents or surfactants is much more feasible from an enzymatic point of
view than using whole cells;
the production of enzymes at a higher scale, with enhanced stability and/or
activity and at a lower cost is feasible by using recombinant-DNA
technology .
However, a more extensive effort is required to overcome several
bottlenecks: high enzyme cost, low activity and/or stability under
given conditions, low reaction yields and the low biodiversity in
organisms screened so far.
22
23. REFERENCES
Khopkar.S.M, Environmental Pollution Monitoring and Control, Newage
publishers,2007.
Miguel Alcalde, Manuel Ferrer, Francisco J. Plou and Antonio Ballesteros;
2006; Environmental biocatalysis: frommremediation with enzymes to novel
green processes; TRENDS in Biotechnology; Vol.24; No.6; 1-7.
Timothy P. Ruggaber and Jeffrey W. Talley; 2006, Enhancing Bioremediation
with Enzymatic Processes; 1-13.
M.A. Rao, R. Scelza, R. Scotti and L. Gianfreda; 2010; Role of enzymes in the
remediation of polluted environments; Soil science. Plant nutrition, 10(3): 333353
R. S. Peixoto, A. B. Vermelho, and A. S. Rosado; 2011; Petroleum-Degrading
Enzymes: Bioremediation and New Prospects; Volume 2011; 1-7.
Chandrakant S. Karigar and Shwetha S. Rao, 2011, Role of Microbial Enzymes
in the Bioremediation of Pollutants,Enzyme Research, Volume 2011,1-11.
Palanivelan Ramachandran,Rajakumar Sundharam,Jayanthi Palaniyappan and
Ayyasamy Pudukkadu Munusamy, 2013, Potential process implicated in
bioremediation of textile effluents, Advances in Applied Science Research,
4(1),131-145.
23