biotechnology Flashcards
what is biotechnology
use of living organisms or parts of living organisms in industrial processes
encompasses gene technology, gene modification, selective breeding, cloning, use of enzymes in industry and immunology
examples of use of biotechnology in industry
produce food, drugs
remove toxic materials= bioremediation
reasons why m/o are used in biotechnology
no welfare issues to consider
enormous range of m/o
can be artificially manipulated by GE relatively easily e.g. human insulin
m/o dint produce unproductive cells/tissues
nutrient requirements simple and cheap
short life cycles
huge quantities produced when given growth requirements
lower temp and pressure required than if use chem engineering
not climate dependent
standard m/o life cycle
reproduce as often as every 20-30 minutes under ideal conditions
reasons why m/o’s are used in biotechnology: no welfare issues to consider
fewer ethical issues than keeping livestock (all that is needed is optimum conditions)
animals would need health checks
reasons why m/o’s are used in biotechnology: enormous range of m/o’s
capable of carrying out many different chemical reactions
reasons why m/o’s are used in biotechnology: do not produce unproductive cells or tissues
products often released so easy to harvest products purer
reasons why m/o’s are used in biotechnology: economic considerations (nutrient requirements are simple and cheap)
can feed on waste/byproducts from other industries
can be GM easily to utilise materials otherwise wasted
reasons why m/o’s are used in biotechnology: lower temp and pressure needed than in chem engineering
cheaper product
saves fuel and cuts emissions
reasons why m/o’s are used in biotechnology: not climate dependent
processes can take place anywhere in the world
why are fermenter conditions kept at optimum and sealed
optimum for growth to maximise product yield
sealed aseptic unit to avoid contamination from m/o’s from air
prevents growth of unwanted bacteria which would compete w culture m/o for nutrients and space, decreasing yield of product. may also produce toxic chemicals which may spoil product, destroy cultured m/o and products. (in food/medicine: all product must be discarded in this instance)
fermenter: how is pH regulated
why
acid/base added
pH probe to measure pH so monitored and can be maintained at optimum for enzyme activity eg respiration
prevents denaturing
fermenter: how is temp regulated
why
temperature probe measures temp for optimum enzyme activity e.g. for respiration
prevents denaturing
cooling jacket and cold-water inlet cool bc respiration releases heat
fermenter: what does impeller do
ensures nutrients evenly distributed and keeps temp even
mixes m/o
fermenter: what does sparger do
distributes O2 evenly
fermenter: what does compressed air do
sterile air, provides O2 in aerobic fermenter
enables aerobic conditions
fermenter: what does steam do
sterilisation
kills contaminating m/o’s so they cannot compete w culture m/o for nutrients and space so increased yield
fermenter: what does antifoam do
removes foam
stops it clogging pipes
so can use fermenter for longer
primary metabolite example
ethanol from Saccharomyces cerevisiae
when is ethanol (1ary metabolite) made and collected
ethanol made as pat of normal growth of the m/o (in log phase) so product curve closely matches the m/o curve
can be collected from fermenter continuously: so maintain conditions continuously
when is continuous fermentation used
when primary metabolite is the required product
what is a primary metabolite
a product synthesised in normal metabolism when the m/o is actively reproducing
describe continuous fermentation
m/o 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 continually removed (medium, m/o, waste and desired products) so culture volume in fermenter is constant
examples of continuous fermentation
single cell protein (Quorn/mycoprotein)
bacteria to produce insulin)
example of secondary metabolite
penicillin from Penicillium crysogenum
when is secondary metabolite eg penicillin made
made when m/o growth slows i.e. in stationary phase
product curve doesnt match growth curve
population kept in closed culture and metabolites collected at end
when is batch fermentation used
when secondary metabolite is required product
when is secondary metabolite synthesised
only shown there is limited nutrient availability in stationary phase
describe batch fermentation
m/o are inoculated Ito a fixed volume of sterile medium
as the growth takes place, nutrients are used up and both new biomass and waste products build up
as the culture reaches stationary phase overall growth ceases but during this phase the m/o often produce the desired end products as secondary metabolites
process stopped before death phase and products are harvested and fermenter is emptied and sterilised and then new batch culture can be started yp
examples of secondary metabolites
penicillin
yoghurt
beer
enzyme for washing powder
batch vs continuous production: fermenter type
B: closed
C: open
batch vs continuous production: used to produce what type of metabolite
B: 2ary (made in stationary phase)
C: 1ary (made in exponential phase)
batch vs continuous production: time period
B: culture grown for fixed time period
C: culture grown continuously
batch vs continuous production: nutrients added when
B: nutrients added at beginning only
C: nutrients added continuously once it reaches exponential growth