biotechnology Flashcards
what is the definition of biotechnology?
the use of living organisms in industrial processes to produce food/drugs through genetic modification, cloning, and selective breeding.
describe 5 reasons why micro-organisms are used in biotechnological processes
- less ethical issues than keeping livestock.
- short life cycles so large populations can be grown very quickly in reaction vessel.
- requires lower temps so cheaper product and saves fuel emissions.
- NOT climate dependant and so processes can take place anywhere in the world.
- can be used in genetic engineering to produce human insulin.
explain the function cold-water inlet and why it is useful in an industrial fermenter
allows circulation of water around the fermenter to regulate temperature. If a product is allowed to build up, it may affect synthesis of a product.
explain the function sterile nutrient medium and why it is useful in an industrial fermenter
provides oxygen in aerobic fermenters - it allows micro-organisms to respire and allow synthesis of product. It is a source of carbon, nitrogen, minerals and vitamins.
explain the function pH and temp probe and why it is useful in an industrial fermenter
keeps temp and ph in narrow range to prevent denaturing of enzyme/inactivity of enzyme if too cold.
what must be done to the antifoam in the industrial fermenter
sterilise fermenter to reduce foam clumping as pipe could have contaminating bacteria, which reduces competitive exclusion
name a primary metabolite
ethanol
name a secondary metabolite
penicillin
what is the function of ethanol
used in continuous fermentation
provides optimum conditions for growth.
describe continuous fermentation
microorganism are inoculated into sterile medium and start to grow.
sterile nutrient medium is continuously added to the culture once it reaches the exponential point of growth.
culture broth is continuously removed so culture volume in fermenter is constant.
describe batch fermentation
closed culture - limited nutrients available in stationary phase.
microorganism are inoculated into a fixed vol of sterile medium.
as growth takes place, nutrients are used up and both new biomass and waste products build up.
as culture reaches stationary phase overall growth stops but the microorganism often produce the desired end product as secondary metabolites.
process stopped before death phase and products harvested and new batch started up. e.g. yoghurt, cheese.
when is penicillin made?
in times of stress! - when microorganism growth slows at stationary phase
culture difference between batch and continuous
batch = closed culture
continuous = open culture
what phase is batch fermentation in
stationary phase
what phase is continuous fermentation in?
exponential phase
difference between batch and continuous in terms of inoculation
batch = inoculated in fixed volume of sterile medium
cont. = nutrient continuously added once it reaches exponential growth.
in batch fermentation, exponential growth is…
short - slower growth rates due to limiting factors.
in continuous fermentation, exponential phase is…
long - fast growth is maintained.
examples of batch fermentation
wine, beer, yoghurt, cheese
examples of continuous fermention
quorn, mycoprotein, human insulin