Coreconceptsofbiochemicalengineering1 150509053327 Lva1 App6891
-
Upload
tamoor-tariq -
Category
Documents
-
view
219 -
download
0
description
Transcript of Coreconceptsofbiochemicalengineering1 150509053327 Lva1 App6891
-
Core Concepts of Biochemical Engineering
Presented by: Raja Wajahat
-
Introduction
Biotechnology
Biotechnology is the art and science of converting reactants intouseful products by the action of microorganisms or enzymes.
Examples:
production of a particular chemical, production of better plants/seeds,use of specially designed organisms to degrade wastes
Bio-processing
Any process in which microorganisms play an essential role in getting transformation of feed into useful products is called as bio-processing.
2
Presented by Raja Wajahat
-
Biochemical Engineering
Biochemical Engineering is the extension of chemical engineering principles to systems using a biological catalyst to bring about desired
chemical transformations.
It is usually divided into biochemical reaction engineering and bio separations.
Biochemical Engineering is an important area in modern biotechnology.
3
Presented by Raja Wajahat
-
Biochemical Engineering
Cells culture be scaled up, biological products be separated, purified and prepared on a large scale.
Biochemical engineering is expected to carry out the above tasks and to bring about huge economic benefits in realizing sustainable
development.
4
Presented by Raja Wajahat
-
Biochemical Engineering
It is the key to biotechnology development to intensify the researches into biological reactors and the separation, purification technologies
for biological products.
And biochemical engineering has been playing an increasingly important role in the above research fields.
5
Presented by Raja Wajahat
-
Difference between bioprocess
and biochemical engineering
In addition to chemical engineering, bioprocess engineering would include the work of mechanical, electrical and industrial engineers to
apply the principles of their disciplines to processes based on using
living cells.
Biologists and Engineers differ in their approach to research
6
Presented by Raja Wajahat
-
Difference between bioprocess
and biochemical engineering
In life sciences, mathematical theories and quantitative methods (except statistics) have played a secondary role.
Results are qualitative and descriptive models are formulated and tested.
However, biologists are very strong with respect to laboratory tools and interpretation of laboratory data from complex systems.
7
Presented by Raja Wajahat
-
Difference between bioprocess
and biochemical engineering
Engineers possess good background in the physical and mathematical sciences
Quantitative models and approaches even to complex systems are strengths
The skills of engineer and life scientist are complimentary
8
Presented by Raja Wajahat
-
Traditional and Modern Applications
of
Biotechnology/Bio-processing
Traditional
Foods, bakery products, beverages, wine from fruit juices, fermentation of milk to make curd
Modern
Commercial production of antibiotics, vaccines, fermented foods, organic acids etc.
9
Presented by Raja Wajahat
-
Biochemistry
Presented by Raja Wajahat
10
-
What is Biochemistry?
Study of life cyclic processes in terms of chemicals
How life cycle proceeds with mutual cooperation of various activitiesof living beings
Energy is released by breaking of the high energy storing moleculesusually phosphate containing molecules
Oxidation of NADH (nicotinamide adenine dinucleotide ) in themitochondria is one of the main reactions
11
Presented by Raja Wajahat
-
Biochemistry
Some of the chemical/biochemical reactions in the living organisms are facilitated by another type of compounds called enzymes
Facilitation of a reaction is called as catalysis
Hence enzymes are called as biocatalysts or biological catalysts
Cells themselves contain some of the enzymes
12
Presented by Raja Wajahat
-
Biochemistry
Living organisms contain various bimolecules which are the building blocks of the cell and also help in storing and releasing energy for
biotransformations
Living organisms contain a large number of bimolecules and they are essentially composed of carbon and nitrogen. The
bimolecules have high molecular weights and are complex in
structure
They include carbohydrates, lipids, proteins, nucleic acids, vitamins etc.
13
Presented by Raja Wajahat
-
Important Biomolecules
Carbohydrates
Lipids
Proteins
Nucleic acids
Presented by Raja Wajahat
14
-
Carbohydrates
Carbohydrates are made from monomers called monosaccharides.
Some of these monosaccharides include glucose (C6H12O6), fructose (C6H12O6), and deoxyribose (C5H10O4).
When two monosaccharides undergo dehydration synthesis, water is produced, as two hydrogen atoms and one oxygen atom are lost from
the two monosaccharides' hydroxyl group.
Presented by Raja Wajahat
15
-
Carbohydrates
Presented by Raja Wajahat
16
-
Carbohydrates
Presented by Raja Wajahat
17
-
LIPIDS
Lipids are usually made from one molecule of glycerol combined with other molecules.
In triglycerides, the main group of bulk lipids, there is one molecule of glycerol and three fatty acids.
Fatty acids are considered the monomer in that case, and may be saturated (no double bonds in the carbon chain) or unsaturated (one or
more double bonds in the carbon chain).
18
Presented by Raja Wajahat
-
LIPIDS
Lipids, especially phospholipids, are also used in various pharmaceutical products,
either as co-solubilisers (e.g., in parenteral infusions) or
else as drug carrier components (e.g., in a liposome or transfersome).
19
Presented by Raja Wajahat
-
LIPIDS
Presented by Raja Wajahat
20
-
LIPIDS
Class of compounds which are fatty/oily in nature and present in cells and tissues
In addition to fats and oils, some other biological materials including waxes, cholesterol and some vitamins and hormones are also
classified as lipids.
General structure of fats and oils
Triglycerides are formed due to the reaction of alcohol glycerol and long chain fatty acids such as stearic acid
21
Presented by Raja Wajahat
-
Lipid Structure
Presented by Raja Wajahat
22
-
Characteristics of Lipids
Insoluble in water
Soluble in non-polar solvents including hexane, chloroform etc
Release a lot of energy on breakdown and therefore considered as the energy storage media
Contain a large proportion of C-H bonds
Upon saponification, release fatty acids and glycerol
They are synthesized by the cells from sugars
Some lipid compounds such as vitamins and hormones have intense biological activity
23
Presented by Raja Wajahat
-
Characteristics of Lipids
As bimolecules, they are constituted of cells wall and form a protective coating to the cell and encourage some species.
They are also energy carriers and release energy as and when cell requires it
24
Presented by Raja Wajahat
-
Characteristics of Lipids
Lipids also include a heterogeneous group of structural component.
Some lipids are combined with other classes of compounds and they are known as:
Lipoproteins,
Proteolipids,
Lipoamino acids,
Phosphatidopeptides,
Lipopolysaccharides
25
Presented by Raja Wajahat
-
Proteins
Proteins are very large molecules macro-biopolymers made from monomers called amino acids.
There are 20 standard amino acids, each containing a carboxyl group, an amino group, and a side-chain (known as an "R" group).
The "R" group is what makes each amino acid different, and the properties of the side-chains greatly influence the overall three-
dimensional conformation of a protein.
When amino acids combine, they form a special bond called a peptide bond through dehydration synthesis, and become a polypeptide, or
protein.Presented by Raja Wajahat
26
-
Proteins
Presented by Raja Wajahat
27
-
Proteins
Presented by Raja Wajahat
28
-
Proteins
In order to determine whether two proteins are related, or in other words to decide whether they are homologous or not, scientists use
sequence-comparison methods.
Methods like Sequence Alignments and Structural Alignments are powerful tools that help scientists identify homologies between
related molecules.
The relevance of finding homologies among proteins goes beyond forming an evolutionary pattern of protein families.
By finding how similar two protein sequences are, we acquire knowledge about their structure and therefore their function.
Presented by Raja Wajahat
29
-
Nucleic acids
Nucleic acids are the molecules that make up DNA, an extremely important substance that all cellular organisms use to store their
genetic information.
The most common nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
Their monomers are called nucleotides.
A nucleotide consists of a phosphate group, a ribose sugar, and a nitrogenous base.
Presented by Raja Wajahat
30
-
Nucleic acids
The phosphate group and the sugar of each nucleotide bond with each other to form the backbone of the nucleic acid, while the sequence of
nitrogenous bases stores the information.
The most common nitrogenous bases are adenine, cytosine, guanine, thymine, and uracil.
Presented by Raja Wajahat
31
-
Nucleic acids
The nitrogenous bases of each strand of a nucleic acid will form hydrogen bonds with certain other nitrogenous bases in a
complementary strand of nucleic acid (similar to a zipper).
Adenine binds with thymine and uracil; Thymine binds only with adenine; and cytosine and guanine can bind only with one another.
Presented by Raja Wajahat
32
-
Nucleic acids
Presented by Raja Wajahat
33
-
GENERALIZED VIEW OF BIOPROCESSRAW MATERIALS
UPSTREAM PROCESSES
Inoculum
Preparation
Equipment
Sterilization
BIOREACTOR - FERMENTER
Reaction Kinetics
and
Bioactivity
Transport Phenomena
and Fluid Properties
DOWNSTREAM PROCESSES
SeparationRecovery and
Purification
THE BOTTOM LINE
REGULATIO
N
ECONOMIC
S
HEALTH AND
SAFETY
Waste Recovery,Reuse and
Treatment
Instrumentation
and Control
Media Formulation
and
Sterilization
34
Presented by Raja Wajahat
-
Microbiology
Presented by Raja Wajahat
35
-
Microbiology
Microbiology is the study of microscopic organisms, those being unicellular (single cell), multicellular (cell colony), or acellular
(lacking cells).
Microbiology encompasses numerous sub-disciplines including virology, mycology, parasitology, and bacteriology.
36
Presented by Raja Wajahat
-
Microbiology
Eukaryotic micro-organisms possess membrane-bound cell organelles and include fungi and protists, whereas prokaryotic organismswhich all are microorganismsare conventionally classified as
lacking membrane-bound organelles and include eubacteria and
archaebacteria.
Microbiologists traditionally relied on culture, staining, and microscopy.
However, less than 1% of the microorganisms present in common environments can be cultured in isolation using current means
Microbiologists often rely on extraction or detection of nucleic acid,
either DNA or RNA sequences.
37
Presented by Raja Wajahat
-
Microbiology
Viruses have been variably classified as organisms, as they have been considered either as very simple microorganisms or very complex
molecules.
Prions, never considered microorganisms, have been investigated by virologists, however, as the clinical effects traced to them were
originally presumed due to chronic viral infections, and virologists
took searchdiscovering "infectious proteins".
38
Presented by Raja Wajahat
-
Microbiology
As an application of microbiology, medical microbiology is often introduced with medical principles of immunology as microbiology
and immunology.
Otherwise, microbiology, virology, and immunology as basic sciences have greatly exceeded the medical variants, applied sciences
39
Presented by Raja Wajahat
-
Microbiology
Study of microscopic organisms
Important branch of science
As a basic biological science
Deals with nature of life processes and principles behind, genetics
As an applied biological science
Study of useful as well as pathogenic microorganisms
40
Presented by Raja Wajahat
-
Why microbiology is
important?
In biochemical engineering
To understand and analyze the process of biotechnology
Design and operate different units in rational a way
Therefore, a basic knowledge of cell growth and function is required
A living microorganism may be conceptualized as a chemical reactor (take nutrients from environment, grows, reproduces and releases products)
Products formed and released during cellular activities could be commercially important
41
Presented by Raja Wajahat
-
Why microbiology is
important?
Rates of nutrient utilization, growth and release of products depends
upon:
Type of the cells involved
Temperature
Composition of media etc.
Quantitative understanding of biological systems (correlation of friction factor and Reynolds No.)
Understanding above interactions requires a foundation built on microbiology and biochemistry
42
Presented by Raja Wajahat
-
Industrial Microbiology
Study of the exploitation of the biochemical potential of microbes for the production of various products
Antibiotics, vaccines, steroids, solvents, vitamins etc.
Developments of new products using genetic engineering
43
Presented by Raja Wajahat
-
What Are Microorganisms?
Microorganisms are actually a diverse group of organisms.
The fact that theyre micro isnt even true of all microorganisms
some of them form multicellular structures that are easily seen with the naked eye
Presented by Raja Wajahat
44
-
What Are Microorganisms?
There are four main kinds of microorganisms, based on evolutionary
lines:
Bacteria are a large group of unicellular organisms that scientists loosely group as Gram-negative and Gram-positive, but in reality
there are many different kinds.
The bacteria and archaea are often talked about together under the heading of prokaryotes because they lack a nucleus. They do share a few characteristics and arent easily distinguished from one another at first, but they are distinct groups.
Presented by Raja Wajahat
45
-
What Are Microorganisms?
Archaea are another group of unicellular organisms that evolved along with bacteria several billion years ago.
Many are extremophiles, meaning that they thrive in very hot or very acidic conditions.
Archaea are more closely related to eukaryotes than to bacteria.
Presented by Raja Wajahat
46
-
What Are Microorganisms?
Eukaryotic microorganisms are a structurally diverse group that includes protists, algae, and fungi.
They all have a nucleus and membrane-bound organelles, as well as other key differences from bacteria and archaea.
All the rest of the multicellular organisms on earth, including humans, have eukaryotic cells as well.
Presented by Raja Wajahat
47
-
What Are Microorganisms?
Presented by Raja Wajahat
48
-
What Are Microorganisms?
Viruses are smaller than bacteria and are not technically alive on their own they must infect a host cell to survive.
Viruses are made up of some genetic material surrounded by a viral coat, but they lack all the machinery necessary to make proteins and
catalyze reactions.
This group also includes subviral particles and prions, which are the simplest of life forms, made of naked ribonucleic acid (RNA) or
simply protein.
Presented by Raja Wajahat
49
-
Genetic Engineering50
Presented by Raja Wajahat
-
Microscopy
Microorganisms are measured in smaller units such as microns, nanometers, mill microns and Angstrom
Various microscopes
Difference between ordinary and electron microscope
51
Presented by Raja Wajahat
-
Range of microscopic
measurements
52
Presented by Raja Wajahat
-
Building block of organisms
All living organisms are composed of cells
What is true for Escherichia coli is true for elephants
Cells are b/w 1 and 50 micrometer in diameter
Basic components of living cell
Cytoplasm
Cell membrane
Nucleus
Ribosome
53
Presented by Raja Wajahat
-
Cell Nucleus (DNA Structure)54
Presented by Raja Wajahat
-
Cell components55
Presented by Raja Wajahat
-
DNA
DNA determines
Heredity
Cell reproduction
Protein synthesis
When DNA is damaged by
foreign substances, various
toxic effects, including:
Mutations
Cancer
Birth effects
Defective immune system
56
Presented by Raja Wajahat
-
Cell Membrane
Acts as a barrier from external environment
It closes the cell and regulates the passage of ions, nutrients, metabolic products and fat soluble substances into and out of it
It is composed of phospholipid bilayer about 8 nm thick
Highly selective membrane enabling the cell to concentrate specific metabolites and excrete waste
A number of complex transformation takes place across the membrane
57
Presented by Raja Wajahat
-
Cytoplasm58
Presented by Raja Wajahat
-
Cytoplasm
Colloidal in nature
Thick semi-transparent and has higher water contents
It contains:
Hydrophilic components (protein particles, carbohydrates and salts)
Hydrophobic components (lipids or fats)
Main function of cytoplasm is absorption and excretion
59
Presented by Raja Wajahat
-
Prokaryotes and Eukaryotes
Prokaryotic cell
Genetic material is not enclosed within the
membrane
Cell walls contain complex polysaccharide
peptidoglycan
Simple method of reproduction
Size is usually 0.5 to 3 micrometer in diameter
Eukaryotic cell
Eukaryote means true nucleus
Genetic material enclosed in a specialized membrane
They are larger and more complex than prokaryotes
Size range from 2 to 200 micrometer
60
Presented by Raja Wajahat
-
Applications of Prokaryotes
Metabolically the most diverse of all living systems
Responsible for most degradation processes
Can be grown aerobically and anaerobically
Form a wide range of organic products (this property has both positive and negative impact on society)
61
Presented by Raja Wajahat
-
Applications of Prokaryotes
Positive
represent a massive resource of biocatalysis for the biotransformation of organic materials and the degradation of herbicides, insecticides and other man-made chemicals
Negative
Represent the principal agents causing the deterioration of biomaterial e.g food and wood and are major hazards to public health (food poisoning and other diseases)
62
Presented by Raja Wajahat
-
Classification of organisms
Classified according to their structure and function
Divided into three kingdoms
Plants
Animals
Protists (Neither plants nor animals)
Most are unicellular but some have many cells
Cells have a membrane around the nucleus (eukaryotes)
63
Presented by Raja Wajahat
-
Classification of organisms
Classifications show differences in several characteristics including:
Energy and nutritional requirements
Rates of growth and product release
Method of reproduction
Morphology
64
Presented by Raja Wajahat
-
Classification of organisms65
Presented by Raja Wajahat
-
Naming the microorganisms
They are named in Latin using binary nomenclature
First name represents the group or genus
Second name represents the species
Escherichia coli C600
National collection of industrial and marine bacteria (NCIMB)
American type culture collection (ATCC)
Strain (A strain is a subset of a bacterial species differing from other bacteria of the same species by some minor but identifiable difference)
66
Presented by Raja Wajahat
-
Escherichia coli (E. coli)
Escherichia coli (E. coli) chosen as a test microorganism.
E. coli is currently the most specific indicator for faecal contamination of a water source and therefore it is considered as a
model organism in laboratory research.
The cells are about 2 m long and 0.5 m in diameter, with a cell volume of 0.6 0.7 m3 (Kubitschek, 1990).
Presented by Raja Wajahat
67
-
Escherichia coli (E. coli)
Presented by Raja Wajahat
68
-
Escherichia coli (E. coli)
Optimal growth of E. coli occurs at 37C. Under a microscope,
E. coli is a rod-shaped prokaryotic cell which has a long, rapidly rotating flagellum (tail) used for movement.
A strain of E. coli is a sub-group within the species that has unique characteristics that distinguish it from other E. coli strains.
69
Presented by Raja Wajahat
-
Escherichia coli (E. coli)
These differences are often detectable on the molecular level and may result in changes to the physiology or life cycle of the bacterium.
For example, a strain may gain pathogenic capacity or the ability to resist antimicrobial agents.
Different strains of E. coli are often host-specific, making it possible to determine the source of faecal contamination in environmental
samples.
70
Presented by Raja Wajahat
-
Different Bacteria
Pseudomonas aeruginosa (P. aeruginosa)
is a gram-negative rod shaped free living bacterium that is ubiquitous in the environment
Staphylococcus aureus (S. aureus)
is a gram positive bacterium usually arranged in grape like irregular clusters.
Although it occurs widely in the environment it is found mainly on skin and the mucous membranes of animals.
71
Presented by Raja Wajahat
-
Different Bacteria
S. aureus can be released into environments including swimming pools, spa pools and other recreational waters by human contact.
Legionella pneumophila (L. pneumophila)
is a gram negative rod shaped bacterium.
72
Presented by Raja Wajahat
-
Yeasts
Rhodosporidium turoloides (R. turoloides)
Y4 is oil producing or oleaginous yeast (Wu et al. 2011).
Since these species contain intracellular valuable compounds such as lipids, therefore the disruption of this yeast would be interesting in
order to release the lipids contained in vacoules within the yeast cell.
Once the lipids are released biodiesel could be produced via a conventional trans-esterification process.
73
Presented by Raja Wajahat
-
Enzymes
Presented by Raja Wajahat
74
-
What are Enzymes?
Enzymes are biological catalysts and are one of the essentialcomponents of all living systems
Biochemical reactions occur rapidly through the mediation of naturalcatalysts called enzymes
Enzymes are bimolecules that catalyze (increase the rates of)chemical reactions
Enzymes have a key role in catalysing the chemical transformationsthat occur in all cell metabolism without themselves undergoing any
overall change
75
Presented by Raja Wajahat
-
Enzymes
Some generic terms associated with enzymology:
Cofactor: the non-protein content of enzyme
Coenzyme: an enzyme with organic molecules as its cofactor
Haloenzyme: an active enzyme including cofactor
Apoenzyme: the inactive portion of protein
The nature and specificity of their catalytic activity is basically due to the three dimensional structure of folded protein (determined by the
sequence of amino acids)
76
Presented by Raja Wajahat
-
Classification of Enzymes
Enzymes are usually named in terms of the reactions that are catalysed
Usual practice is to add ase to the major part of the name of the substrate e.g Urease, Urginase (urginine)
Enzymes are also classified by groups that catalyse similar reactions (see slide 17)
77
Presented by Raja Wajahat
-
Properties of enzymes
The catalytic activity of enzymes differs from that of other catalysts
Efficiency
Turn over number= molecules reacted per catalytic site per unit time
Turn over number for enzymes at room temperature are usually much higher than for industrial chemical catalysts
78
Presented by Raja Wajahat
-
Specificity of enzymes
Specificity
A characteristic feature of enzymes is that they are specific in action, some showing complete specificity for only one type of
molecule
If a substance exists in two stereochemical forms, L and D isomers, enzymes may recognize only one of the two forms for example
glucose oxidase will oxidise D(+) glucose only and no other hexose
isomer.
79
Presented by Raja Wajahat
-
Specificity of enzymes
Active centre/Active site
A catalyst site on the molecule is called active site/active centre. Such sites constitute only a small proportion of the total volume
of the enzyme and are located on or near the surface.
The active site is usually a very complex physico-chemical space, creating microenvironments in which the binding and
catalytic areas can be found.
The forces operating at the active centre can involve
Charge, hydrophobicity, hyfrogen bonding and redoxprocesses
80
Presented by Raja Wajahat
-
How the biological catalysts work?
A reaction proceeds according to the two possible theories
Collision theory
Proposes that reactions take place by the collision of the reactant molecules. More is the concentration of the
reactants, more are the chances for the reactants to collide
and hence more will be the rate of reaction. However, all
collisions may not necessarily result in the reaction to
proceed to produce products
81
Presented by Raja Wajahat
-
How the biological catalysts work?
Transition state theory
Propose that the collision of certain molecules which have crossed certain potential energy barrier alone will result in
the reaction to take place. This potential energy barrier is
known as activation energy
82
Presented by Raja Wajahat
-
Biological catalysts
Like all catalysts, enzymes work by lowering the activation energy for a reaction thus increasing the reaction rate
Not consumed by the reaction
Do not alter the equilibrium
Enzymes differ from most other catalysts by being much more specific
Enzymes are know to catalyze about 4000 biochemical reactions
83
Presented by Raja Wajahat
-
Types of specificity
Depending upon the reaction conditions and the specific nature of t5he enzymes, the enzymatic catalytic process exhibits different kinds
of specificity including;
Group specificity
Stereochemical specificity
Product specificity
Substrate specificity
84
Presented by Raja Wajahat
-
Enzymatic process 85
Presented by Raja Wajahat
-
Enzyme specificity hypothesis
Several hypothesis have been proposed to explain the enzyme specificity in catalytic activity and its ability to interact with the
substrates
Fischer lock and key hypothesis
It was proposed by Fischer in 1890 who conceived the concept of complementary structural features between the
enzyme and the substrate
86
Presented by Raja Wajahat
-
Fischer lock and key hypothesis
The catalytic process is brought about because the substrate fits into the complementary site on the enzyme just as key
fits into the lock
Thus, the reacting group of the substrate gets struck with the catalytic site of the enzyme
Similarly, the binding groups attach to the binding sites in the enzyme
Hypothesis has been successful in explaining many features of the enzyme specificty
87
Presented by Raja Wajahat
-
Fischer lock and key hypothesis88
Presented by Raja Wajahat
-
Fischer lock and key hypothesis
Drawback
Could not explain some of the conformational changes taking place in the enzymes when they come in contact with the
substrate
An enzyme may not be having exactly complementary feature that is compatible to the substrate, but still there are cases where
reaction have taken place
89
Presented by Raja Wajahat
-
Fischer lock and key hypothesis
Drawback
X-ray diffraction analysis and some spectroscopic analysis have shown differences in the structures of free enzymes and substrate
bound enzymes.
This was explained by Koshland in 1958 with his Koshlandinduced-fit hypothesis
90
Presented by Raja Wajahat
-
Koshland induced-fit hypothesis91
Presented by Raja Wajahat
-
Koshland induced-fit hypothesis
This hypothesis proposes that the structure of the substrate may not be complementary to the enzyme in its native format,
but it is complementary to the active site in the substrate-enzyme complex.
Both the enzyme and the substrate change their structure slightly to accommodate each other.
92
Presented by Raja Wajahat
-
Versatility
Enzymes catalysis is shown by the type of reactions that can be catalysed. Six groups of enzymes are recognized according to their reactivity
1. Oxidoreductase.oxidation-reduction reactions
2. Transferases..transfer of atom b/w two molecules
3. Hydrolases..hydrolysis reactions
4. Lyases.removal of a group from a substrate
5. Isomerases..isomerisation reactions
6. Ligasescatalyse the synthesis of various types of bonds where the reactions are coupled with breakdown of energy-containing materials such as ATP
93
Presented by Raja Wajahat
-
Difference b/w catalyst and enzyme
Function:
Catalysts are substances that increase or decrease the rate of a chemical reaction but remain unchanged.
Enzymes are proteins that increase rate of chemical reactions converting substrate into product.
Molecular weight:
Low molecular weight compounds.
High molecular weight globular proteins.
94
Presented by Raja Wajahat
-
Difference b/w catalyst and enzyme
Types:
There are two types of catalysts positive and negative catalysts.
There are two types of enzymes - activation enzymes and inhibitory enzymes.
Alternate terms:
Inorganic catalyst. Organic catalyst or bio catalyst.
Nature:
Catalysts are simple inorganic molecules
Enzymes are complex proteins
95
Presented by Raja Wajahat
-
Difference b/w catalyst and enzyme
Reaction rates:
Typically slower Several times faster
Specificity:
They are not specific and therefore end up producing residues with errors Enzymes are highly specific producing large amount of good residues
Conditions:
High temp, pressure
Mild conditions,
96
Presented by Raja Wajahat
-
Difference b/w catalyst and enzyme
Enzymes are proteins, which act as catalysts.
Enzymes lower the energy required for a reaction to occur, without being used up in the reaction.
Many types of industries, to aid in the generation of their products, utilize enzymes.
Examples of these products are; cheese, alcohol and bread.
97
Presented by Raja Wajahat
-
Fermentation
Fermentation is a method of generating enzymes for industrial purposes.
Fermentation involves the use of micro organisms, like bacteria and yeast to produce the enzymes.
There are two methods of fermentation used to produce enzymes.
98
Presented by Raja Wajahat
-
Fermentation
These are submerged fermentation and solid-state fermentation.
Submerged fermentation involves the production of enzymes by microorganisms in a liquid nutrient media.
Solid-state fermentation is the cultivation of microorganisms, and hence enzymes on a solid substrate.
99
Presented by Raja Wajahat
-
Enzymes
Carbon containing compounds in or on the substrate are broken down by the micro organisms, which produce the enzymes either
intracellular or extracellular.
The enzymes are recovered by methods such as centrifugation, for extracellular produced enzymes and lysing of cells for intracellular
enzymes.
100
Presented by Raja Wajahat
-
Enzymes
Many industries are dependent on enzymes for the production of their goods.
Industries that use enzymes generated by fermentation are the brewing, wine making, baking and cheese making
101
Presented by Raja Wajahat
-
Immobilization of Enzymes
Presented by Raja Wajahat
102
-
Immobilized Enzymes
The remarkable catalytic properties of enzymes make them veryattractive for use in processes where mild chemical conditions and
high specificity are required.
Cheese manufacture has traditionally used rennet, an enzymepreparation from calf stomach, as a specific protease which leads to
the precipitation of protein from milk.
103
Presented by Raja Wajahat
-
Immobilized Enzymes
Mashing in the malting of grain for the brewing of beer makes useof pamylase from germinating grain to hydrolyse starch to produce
sugars for the fermentation
stage. In both of these examples the enzymes are not recovered fromthe reaction mixture and a fresh preparation is used for each batch.
104
Presented by Raja Wajahat
-
Immobilized Enzymes
Similarly, in more modern enzyme reaction applications, such as inbiological washing detergents, the enzyme is discarded after single
use but there are, however, situations where it may be desirable to
recover the enzyme.
This may be because the product is required in a pure state or that thecost of the enzyme preparation is such that single use would be
uneconomic.
105
Presented by Raja Wajahat
-
Immobilized Enzymes
To this end, immobilized biocatalysts have been developed where theoriginal soluble enzyme has been modified to produce an insoluble
material which can be easily recovered from the reaction mixture.
Many industrially important micro-organisms tend to agglomerateduring their growth and form flocs suspended in the culture medium
or films which adhere to the internal surfaces of the fermenter.
106
Presented by Raja Wajahat
-
Immobilized Enzymes
This tendency may or may not be advantageous to the process and isdependent on a variety of parameters such as the pH and ionic
strength of the medium and the shear rate experienced in the growth
vessel.
In some cases the formation of substantial flocs is essential to theproper operation of the process.
107
Presented by Raja Wajahat
-
Immobilized Enzymes
In the case of the activated sludge waste water treatment the settlingproperties of the flocculated micro-organisms are utilized in order toproduce a concentrated stream of biomass for the recycle.
The so-called trickling filter, also in widespread use in waste-watertreatment, is reliant on the formation of a film of organisms on thesurfaces of its packing material.
The operation is not that of a filter, in which material would beremoved on the basis of its particle size, but that of a biologicalreactor in which the waste material forms the substrate for the growthof the microbes.
108
Presented by Raja Wajahat
-
Immobilized Enzymes
The presence of the film provides a means of retaining a highermicrobial concentration in the reactor than would be retained in acomparable stirred-tank fermenter.
The formation of flom and films for the retention of high microbialdensities or to facilitate separation of microbes from the growthmedium may be desirable in other instances as well.
However, in some cases the microbe used may neither be amenable tothe natural formation of large flocs nor adhere as surface films, andrecourse may be made to the artificial immobilization of microbes.
109
Presented by Raja Wajahat
-
Immobilization techniques
There are various methods which have been developed for enzymeand microorganism immobilization and some of these have found
commercial application.
The two largest scale industrial processes utilizing immobilizedenzymes are the hydrolysis of benzyl penicillin by penicillin acylase
and the isomerisation of glucose to a glucose-fructose mixture by
immobilized glucose isomerase.
The immobilization techniques used in general may be broadlycategorized as:
110
Presented by Raja Wajahat
-
Immobilization techniques
(a) Physical adsorption on to an inert carrier.
The first of these methods has the advantage of requiring only mildchemical conditions so that enzyme deactivation during the
immobilization stage is minimized.
The natural formation of microbial flocs and films may beconsidered to be in this category, although the subsequent adhesion
of the microbes to the surface may not be a simple phenomenon.
Special materials may be used as supports which provide themicrobes with environments which are particularly amenable to
their adhesion;
111
Presented by Raja Wajahat
-
Immobilization techniques
such materials include foam plastics which provide conditions of lowshear in their pores.
The process may also be relatively cheap but it does tend to have thedrawback that desorption of the enzyme may also occur readily orthat the microbial film may slough and be carried into the bulk of thegrowth medium.
The process is dependent on the nature of the specific enzyme ormicrobe used and its interaction with the carrier and, whilst it iscommon in the case of immobilized microbes, it has found onlylimited application in the case of immobilized enzymes.
112
Presented by Raja Wajahat
-
Immobilization techniques
(b) Inclusion in the lattices of a polymer gel or in micro-capsules.
This method attempts to overcome the problem of leakage byenclosing the relatively large enzyme molecules or microbes in a
tangle of polymer gel or to enclose them in a membrane which is
porous to the substrate.
It is theoretically possible to immobilize any enzyme or micro-organism using these methods but they too have their problems. Some
leakage of the entrapped species may still occur, although this tends
to be minimal.
113
Presented by Raja Wajahat
-
Immobilization techniques
The main problem is due to mass transfer limitations to theintroduction of the necessarily small substrate molecules into the
immobilized structure, and to the slow outward diffusion of the
product of the reaction.
If the substrate is itself a macro-molecule, such as a protein or apolysaccharide, then it will be effectively screened from the enzyme
or microbes and little or no reaction will take place.
114
Presented by Raja Wajahat
-
Immobilization techniques
(c) Covalent binding
Biological catalysts may be made insoluble and hence immobilizedby effectively increasing their size.
This can be done either by chemically attaching them to otherwiseinert carrier materials or by cross linking the individuals to form largeagglomerations of enzyme molecules or micro-organisms.
The chemical reagents used for the linking process are usuallybifunctional, such as the carbo-di-imides, and many have beendeveloped from those used in the chemical synthesis of peptides andproteins.
115
Presented by Raja Wajahat
-
Immobilization techniques
The inert carriers used tend to be hydrophilic materials, such as cellulose and its derivatives,
but in some cases the debris of the original cells has been used, the cells having been broken and then crosslinked with the enzyme and
each other to form large particles.
116
Presented by Raja Wajahat
-
Presented by Raja Wajahat
117
-
Immobilization techniques
The consumption or biotransformation of substrate by immobilizedmicro-organisms results in most cases in the growth of the micro-
organisms.
The growth which gives rise to a significant increase of thickness inan established biofilm, occurs at a rate which is essentially slow in
comparison with the rates of the diffusion processes.
118
Presented by Raja Wajahat
-
Immobilization techniques
Simultaneously, the attrition of biofilms or flocs arising from theeffects of fluid flow tends to maintain their thickness or size, and,
overall, the immobilized system can be considered to be in a steady
state when short time intervals are involved.
The mathematical similarity of enzyme and microbial kinetics thenmeans that a common set of equations can be used to describe the
behavior of both immobilized enzymes and microbial cells.
119
Presented by Raja Wajahat
-
Thank You!
Presented by: Raja Wajahat
Presented by Raja Wajahat
120