Lect 8

Question 1

Microbial products are important in
They grow

Answer 1

Food
Feed
Agriculture
Healthcare
On various medi

Question 2

Microbes produces

Answer 2

Amino acids
enzymes
vitamins
organic acids alcohol
antibiotics
peptides
growth factors
Bioactive metabolites

Question 3

Single cell proteins are
Microbes have …and can grow…
These proteins are either..or …

Answer 3

Purified/edible proteins from microbes
High protein content
Low cost media(ag waste)
Food or feed grade

Question 4

SCP are rich in …which is absent in most plants and animals
First SCP….up to…for…by….

Answer 4

Essential amino acids (lysine/methionine)
Pruteen
70% protein
Pig feed
Oxidation of methanol by methylophilus methylotrophus
Imperial chemical industries

Question 5

Needs and advantages for microbial SCP

Answer 5

sustainable
Cost effective
Relief to agricultural sector
Wide variety of substrate
Fast growth and high yield
Can be tailored
Climate resistant
Pharma and biofuels

Question 6

Production steps

Answer 6

Selection
Fermentation
Harvesting
Processing

Question 7

Selection general criteria

Answer 7

Non toxic
Non pathogenic
Resistant to pH/temp/mineral conc
Cheap and effective substrate
Easy extraction
High yield

Question 8

Algae selection
Ex
Adv
Disadv

Answer 8

Spirulina and chlorella
Solar energy/fast growth/ easy cultivation/60%protein of good quality expect cysteine which contains sulfur

High chlorphyl causes gut problems
Crllulose undigestable by humans
Low cell density 1-2g/l
Costly recovery (filteration/skimming)

Question 9

Fungi selection
Ex
Adv
Disadv

Answer 9

Quorn by venenatum
Tastes like meat so good for animal alternative
Easy recovery by filtration
50-55% good aa

Slow growth
Yeast contamination if not sterilised frequently
Bacterial contamination if ph is higher than 5
Mycotoxin production

Question 10

Bacteria

Answer 10

Methylophilus/bacillus/brevibacterium
Wide substrate range
Fast growth and short generation time

Pathogenic contamination
Endotoxin by gram -ve

Question 11

Fermentation is done in…which is ..or.under….with controlled……usually…..

Answer 11

Fermentor
Glass or stainlesssteel
Sterile conditions
Temp/pH/humidity
Fed batch

Question 12

Harvesting is either by..or…
Afterwards…under..

Answer 12

Centrifugation(yeast and bacteria)
Filtration (filamentous fungi)
Drying, sterile conditions

Question 13

Processing is done to…..like
Protein isolation is done by disrupting…by….

Answer 13

Remove impurities
Carbs,nucleic acids,lipids,salts
Cell wall
Freezing and thawing cycles
Crushing
Grinding
Thermal shock

Question 14

Problems with SCP

Answer 14

High nucleic acid conc then any other protein source leading to high uric acid concentrations leading to gout and kidney stones

Indigestible cell wall
Yeast> nausea, vomiting, gastrointestinal reactions

Algae> chlorophyll

Filamentous fungi» slow growth means high contamination risk, might produce mycotoxins

Question 15

Microbial enzymes are used in
…as they….
Their nature

Answer 15

Metabolic and biochemical reactions
Lower the activation energy
Proteins except for ribozymes
Highly specific

Question 16

Why enzymes from microorganisms not from plants or animals

Answer 16

More active and stable
Large scale production
Easier production/extraction/purification
Limited space and time req
Work in different environments
Independent of seasons

Question 17

Process for enzymes

Answer 17

Slee tion
Media formulation
Production
Recovery and purification

Question 18

Selection rules
Post selection
for enzymes

Answer 18

Maximum quantities of the enzyme in the shortest time possible with minimal byproducts

Strain improvements to optimize enzyme production by mutation or genetic engineering

Question 19

From the organism chosen …can be taken in…

Answer 19

An inoculum
Liquid media

Question 20

Media formulation

Answer 20

All nutrients for adequate growth
Low cost ingredients and nutritionally safe
Optimal pH

Question 21

Production

Answer 21

Submerged fermentation is mainly used
Solid state fermentation is also used for fungal enzymes

Question 22

Fungal enzymes

Answer 22

Amylases
Cellulases
Proteases
Pectinases

Question 23

Purification and extraction
Enzyme is either..or..
Then…

Answer 23

Extracellular, excreted/ intracellular in the cell
Precipitated using solvents like acetone or alcohol

Question 24

Last steps fpr enzyme
Either drying by…or…
Commercial enzyme maybe ….or…
Sold in …form or…

Answer 24

Filtering and drying
Low temp
Vacuum drying
Crude/ highly purified
Dry powder
Concentrates

Question 25

The process of enzyme culturing is called

Answer 25

Seeding

Question 26

Applications of enzymes food and beverages
Who
In what

Answer 26

Amylases/pectinases/cellulases/lactase

Fruit juice for clarification
Baking for improved bread quality
Wine and brewing for flavour and aroma

Question 27

Enzymes in detergent industry
Why
Who

Answer 27

Removal of stains,oils,fats,proteins
Lipase for lipids,protease for proteins,amylase for carbs

Question 28

Textile industry

Answer 28

Cellulase is used to give natural culture and more smooth and glossy appearance

Catalase id used to remove h202 residuals after bleaching

Question 29

Cosmetics

Answer 29

Superoxide dismutase as antioxidant
Moisturising, whitening

Question 30

Paper and pulp
Why

Answer 30

Bleaching and deinking
Xylanase for biobleaching of pulp
Laccases for detoxification of coloured and toxic compounds from pulp

Question 31

Therapeutics

Answer 31

Fibrinolytic enzymes for blood clot dissolving

Asparaginase for treatment of acute lymphocytic leukemia

Question 32

Applications of enzymes

Answer 32

Food and beverages
Detergents
Textile
Therapeutics
Paper and pulp
Cosmetics