Transcript Enzymes in Germination

Enzymes in Germination
Flower Structure
Pollination
Fruit Development
Seed Dispersal
Germination
Test
The seed contains the embryo plant and
cotyledons (starch stores)
Testa
Water enters the seed
through the micropyle
and activates enzymes.
Plumule
(embryo shoot)
The water also softens the
testa to allow it to split.
Radicle
(embryo root)
Cotyledon
Micropyle
Flower Structure
Pollination
Fruit Development
Seed Dispersal
Germination
Test
Enzymes are used in seed germination
Plumule
starch
amylase
secreted
embryo plant
The enzymes break
starch down into
maltose and then
glucose. The glucose is
used in respiration to
provide energy for
growth
maltose
Radicle
This is the first part to
grow out of the seed
as it needs to absorb
more water
Flower Structure
Pollination
Fruit Development
Seed Dispersal
Germination
Test
Enzymes aid in germination
• Seeds imbibe water and swell. The testa softens and
splits.
• Enzymes are activated and the following reactions
take place in the cotyledon where food is stored.
• Starch is broken down to Glucose by Amylase
and Maltase.( energy for growth and making
cell wall)
Enzymes aid in germination
• Insoluble products are converted to solube
forms to facilitate uptake by the growing
seedling.
• Proteins are broken down to Amino Acids by
Proteases(cell membranes, cytoplasm and cell
organelles).
• Any Lipids are broken down to Fatty Acids and
Glycerol by Lipase.
Use of enzymes in biological washing
powder:
• Enzymes are added to washing powders to clean
clothes:
• Lipase is used to clear oily stains. Lipase breaks oils
into simple Fatty acids (colourless) and these are
easily washed by the detergents
• Blood stains and egg stains(proteins basically) are
washed using proteases which break down proteins
to Amino acids (colourless) which is then washed
easily by detergents,
Use of enzymes in biological washing
powder:
• Biological washing powders contain a range of
hydrolysing enzymes. The common enzymes
found in such washing powders are:
• Amylases: break down starch stains
• Cellulases: break down ends of damaged cotton
fibres and remove fuzz produced during washing.
• Lipase: breaks down lipid stains into fatty acids
and glycerol
• Proteases: breaks down protein stains in food
stains.
Role of enzymes in food industry:
• Bacterial amylase is used in fruit juice factory to
remove haze formation
• Microbial cellulose/Pectin on cell wall—fruit juice
factory--- to remove fruit juice from cell walls and
to increase the production---pectinase to break
down----clear juice low viscosity.
• Yeast lactase--- dairy--- to make lactose free milk
and yoghurt, to make ice cream
• Fungal protease ---dairy--- to make cheese (to
replace calf rennin)
Fermenters
Modern fermenters or bio reactors:
• Fermenter is used to grow microorganisms
that produce enzymes on a large scale.
• Conditions inside should be suitable for
optimal metabolism and rapid reproduction of
organisms
• The product should be harvested without
contamination.
Paddle stirrers:
• continuously mix the contents of the
bioreactor.
• Ensures Microorganims(MO) are always in
contact with nutrients
• Ensures an even temperature throughout the
fermentation mixture
• For aerobic fermentations the mixing may be
carried out by an airstream
Microbe input:
• the organism that will carry out the
fermentation process are cultured separately
until they are growing well.
Nutrient input:
The Micro organisms require,
• An energy source- usually carbohydrate
• Growth materials- amino acids (for
ammonium salts which can be converted to
amino acids) for protein synthesis.
Gas outlet:
• Gas maybe evolved during fermentation. This
must be released to avoid pressure build up
and maybe a valuable by product e.g carbon
di oxide is collected and sold for use in fizzy
drinks.
Constant temperature water
jacket
• The temperature is controlled so that it is high
enough to promote enzyme activity but not so
high that enzymes and other proteins in the
microbes are denatured.
Conditions to be controlled
• Aseptic conditions: the fermenter should be sterilised
before use
• Adequate supply of nutrients (amino acids and glucose)
• Filtered air supply for aerobic conditions
• Temperature must be regulated using thermostats and
water jackets
• pH must be maintained optimum. Acidic conditions
should be neutralised using alkalis
• Paddle wheel mixing to make sure all microorganisms are
in touch with nutrients and oxygen
Why are Sterile conditions
essential
• Sterile conditions are essential. The culture
must be pure and all nutrients/equipment
sterile in order to:
• Avoid competition for expensive nutrients
• Limit the danger of disease causing organism
contaminating the product.
Probes:
• monitor conditions such as pH, temperature
and oxygen concentration. Information is sent
to the computer control systems which correct
any changes to maintain the optimum
conditions for fermentation.
Further processing of the
product:
May be necessary in order• To separate the microorganism from the
desired product. In some fermentation
systems these microorganism may then be
returned to the vessel to continue the
process.
• To prepare the product for sale or
distribution, this often involves drying or
crystallisation.