The document discusses enzyme immobilization, defining it as the confinement of enzymes in a specific area while retaining their catalytic activity, which allows for repeated use. It outlines the advantages such as increased efficiency and stability, alongside disadvantages like limited applications and potential activity loss. Various applications of immobilized enzymes in producing antibiotics, steroids, amino acids, and organic compounds are highlighted, along with the types of supports used for immobilization and methods of enzyme attachment.

1. Enzyme Immobilization and
its Applications

2. Introduction
• Enzymes are the biological catalysts that promote
chemical reactions in living organisms
• They have the ability to catalyze reactions under very
mild conditions with high degree of substrate
specificity thus decreasing the formation of byproducts
• Enzymes can catalyze reactions in different states,
individual molecules in solution, in aggregates with
other entities and as attached to surfaces

3. Immobilized enzymes
• “Immobilized enzyme” refers to “enzymes physically
confined or localized in a certain defined region of space
with retention of their catalytic activities, and which can be
used repeatedly and continuously” OR
• Imprisonment of enzyme in a distinct support/matrix.
• The support/matrix allows exchange of medium that
contains substrate of effecter or inhibitor molecules.
• The substrate passes over the immobilized enzyme and is
converted to products.

4. • Advantages
• Increased functional efficiency
• Enhanced reproducibility
• Catalyst Reuse
• Easier Reactor Operation
• Easier Product Separation
• Wider choice of Reactor
• Minimum reaction time
• Less chance of contamination in
products
• High stability
• High enzyme substrate ratio
• Enzyme-free products
• The ability to stop the reaction
rapidly by removing the enzyme
form the reaction solution
Disadvantages
• Limited industrial applications
• Loss or reduction in activity in
some enzymes
• Some enzymes become unstable
• Diffusion limitations
• Additional Cost
• High cost for isolation, purification
and recovery of active enzyme.
• Does not give required results if
one of the substrate is insoluble
• There may be diffusion problems
for the substrate to access the
enzyme under certain conditions

5. Application of immobilized enzymes:
1. Antibiotics Production
Immobilized enzymes are used to produce 6-aminopenicillin acid, penicillin,
cephalosporin.
Penicillin amidase immobilized by covalently binding with amberlite and
crosslinked by glutaraldehyde, or physically adsorbed to bentonite is used for
production of 6-APA (w`w6-aminopenicillanic acid), penicillin V. also ampicillin and
amoxicillin are produced from 6-APA.
Cepholosporins are produced by cephalosporins amidase. Cephalexin and
cephalosporin C can also be produced.
2. Steroid Production
Synthesis of hydrocortisone and prednisolone
3. Amino Acid Production
The production of L-aspartic acid, L-tryptophan and
L- alanine,
4. Acid Production
Acetic acid, Citric acid, L-Malic acid, 2-ketogluconic acid
5. Other organic Compounds
Coenzyme A, FAD (flavin adenine dinucleotide), pyridoxal 5 phosphate, Vitamin
B12, Proinsulin, prostaglandin, interleukin-2.

6. Supports/Matrix used in
immobilization
• The matrix that holds the enzyme should be:
• cheap and easily available.
• Should not react with medium and enzyme.
Three types of matrix are used:
1. Natural polymers: alginate, chitosan and chitin, collagen,
carrageenan, gelatin, cellulose, starch, pectin
2. Synthetic polymers: ion exchange resins/polymers [polyvinyl
chloride (PVC), UV activated Polyethylene glycol (PEG)]
3. Inorganic materials: ceramics, silica, glass, activated carbon,
charcoal

7. Types / methods of immobilization
1. Adsorption
2. Covalent bonding
3. Entrapment
4. Crosslinking
5. Affinity bonding