Tutorial 4 Industrial use of enzymes

Question 1

What are the types of enzymes that we use in food industry based on the type of reaction?

Answer 1

Oxidoreductases
Transferases
Hydrolases
Lyases
Isomerases
Ligases

Question 2

Discuss the benefits of usage of enzymes over chemical catalyst in food industry?

Answer 2

• High production yields due to high catalytic efficiency and high specificity; - Can avoid the disadvantages of many chemical processes such as the development of by-products and unnecessary side reactions
• Allows mild work condition, leads to eco-friendly processes, reducing pollution and saving energy
• Has ability to consistently provide safe and high-quality foods products that meet the needs of current society and regulatory agencies
• Can be inactivated easily
• Purity of the product is better

Question 3

What is the most commonly used enzyme in dairy and meat processing industry and describe its
usage?

Answer 3

Rennet in cheese making specifically involves the hydrolysis of a specific peptide linkage between phenylalanine and methionine residues in the kappa-casein protein present in the milk

Question 4

In which industrial processes do we use enzymes, and how do we inactivate them?

Answer 4

Food, pharmaceutical, meat, dairy, brewing and baking.
Inactivation can be done by heat treatment because it cause protein denaturation of enzyme and enzyme begin to lose its shape causing its inactivation.

Question 5

What are industries that we use Laccase enzyme and what are the environmental applications which is has achieved large-scale level?

Answer 5

Biopolymer industry use laccase in cosmetics, paper and pulp, wood, pharmaceutical, food.
Laccase is an alternative to usage and requirement of large amount of chlorine in chemical pulping process which reduce waste quantity that causes ozone depletion and acidification.

Question 6

Describe the function of Rennet, on caseins and describe its specificity on various casiens?

Answer 6

Rennet in cheese making specifically involves the hydrolysis of a specific peptide linkage between phenylalanine and methionine residues in the kappa-casein protein present in the milk.
Alpha and beta caseins are hydrophobic proteins that are readily precipitated by calcium but kappa casein is not calcium precipitated.

Question 7

Among the range of enzymes used in meat processing industry, describe the one enzyme with its function on meat processing

Answer 7

Transglutamine:
= Catalyze formation of lysine covalent bonds between molecules of proteins or within molecules.
= Form effective protein gels that give hardness and elasticity to meat products.

Question 8

How does the Maillard Reaction help to enhance the food flavor and protein content?

Answer 8

Formation of glycosylamine compound then compound isomerases to give ketosamine through random arrangement.
Ketosamine react in different what to produce range of different products.
Small subset contribute to flavour and aroma.
Melanoidins are also formed which contribute to coloration of cooked foods.

Question 9

Describe the enzymatic function in the baking industry?

Answer 9

During baking, alpha-amylases added to the dough for conversion of starch to small dextrins. Dextrins fermented by yeast to improve taste, crust, colour and toasting qualities of bread.

Question 10

Among the enzymes, what are the possible enzymes that we could use for the bioethanol production from plant materials?

Answer 10

Cellulases.
Cellulases will degrade celluloses to release sugar.

Xylanases
Degrade xylin

Lignases
remove lignins from lignocellulose

Pectinases
Hydrolyze pectin to be used in bioethanol production.

All produce sugar for fermentation for bioethanol production

Question 11

Discuss the benefits of usage of microbial enzymes in polymer synthesis and organic synthesis?

Answer 11

Polymer synthesis:

• Environmentally safe process
• Easy to find
• Degrade biologically
• Cheaper

Organic:

• Minimal or no by product formation
• Easier separated
• Less environmental problems

Question 12

What are the common hydrolases used in textile industry? Describe its function on textile
industry (3 enzymes)?

Answer 12

Common hydrolysases:

• Amylase
• Cellulases
• Lacases

Function:
- Biopolishing
-Bioscouring of fabric
- Cotton softening
- denim finishing
- wool finishing
Amylase is used for desizing
cellulase is used for cloth softening
Lacases is used for bleaching and biodyeing

Question 13

Lipases are widely used for the production of the industrial medicines. Describe its usage by one example with relevant information about their function.

Answer 13

Microbial lipases and polyphenol oxidases are involved in the synthesis of methyl glycidate and 3, 4-dihydroxylphenyl alanine (DOPA, for treatment of Parkinson’s disease)

Lipase is used for indigestion, heartburn, allergy to gluten in wheat products (celiac disease), Crohn’s disease, and cystic fibros

Question 14

Describe the usage of enzymes in genetic engineering providing a real time example (eg. cloning)

Answer 14

Restriction endonucleases or restriction enzymes recognize unique base sequences motifs in DNA strand and cleave the backbone between two nucleotides.

Ligases :
Joins a 5’ end of a DNA with a 3’ end of the same or of another strand.

Used in cloning, DNA replication or recombination. RNA to cDNA synthesis. Recombinant DNA.

Question 15

Suggest a method that we could use the industrial enzyme for the recycling process of plastic

Answer 15

PETase allows the bacteria to degrade plastic.
When the PETase-containing bacteria or fungi are administered to PET plastic, they secrete the PETase enzyme, which causes PET polymers to bind to the active site of PETase, allowing the reaction to occur. During the reaction, the enzyme breaks ester bonds in PET.