Batch & Continuous Culture Flashcards
1
Q
What is batch culture?
A
- y axis = log number of microorganisms
- x axis = time
2
Q
What are the 4 phases?
A
lag phase
log phase
stationary phase
death phase
3
Q
What happens in the lag phase?
A
- genes are being activated e.g. lactose permease
- enzymes are being transcribed and translated
- substrate starts being broken down
- slow population growth
4
Q
What happens in the log phase?
A
- Rapid population growth
- abundant nutrients
- cell population is greater than cell death
5
Q
What is the stationary phase?
A
- cell production = cell death
- lack of nutrients / build up of waste products
- carrying capacity reached - maximum population a ecosystem can maintain
6
Q
What is the death phase?
A
- death rate greater than cell production
- lack of nutrients / build up of waste products
- expression of anitmicrobial compounds e.g. pencillium makes pencillin
7
Q
What is the batch culture method?
A
- closed fermentation vessel
- microorganism are added at the start
- Nothing added or removed
- Products are separated at the end
- temperature is controlled e.g. water jacket
- paddles are used to stir the nutrients to make sure they are evenly
distributed - nutrients are depleted at the end
8
Q
What is the continuous culture method?
A
- open fermentation vessel
- nutrients are added and remove products at a constant rate
- we keep the microorganisms growing in the Log phase
- conditions kept constant e.g. temperature and pH, O2, Glucose, etc.
