Fermentation, Recovery & Purification

Question 1

growth of antibiotics

Answer 1

secondary metabolite
only produced after biomass growth ceases
need to ensure conditions @ later stage of fermentation are suitable for antibiotic production

Question 2

prevent antibiotic synthesis

Answer 2

use glucose. glucose produces biomass which shuts of antibiotic synthesis
by choosing carbon source carefully we can improve yield not all carbon sources prevent antibiotic synthesis e.g. lactose, galactose

Question 3

elemental composition of bacteria

Answer 3

carbon (50%), O2, H2, N2, phosphorus

Question 4

media composition

Answer 4

carbon source (glucose), nitrogen source (ammonium chloride, corn steep liquor), phosphate source (phosphate salt), O2 source (air)

Question 5

manufacturing strategy - batch fermentation

Answer 5

batch fermentation ( add media @ start, innoculate with the culture, allow it to grow, harvest)

Question 6

fed - batch?

Answer 6

fed-batch -similar to batch but with a supplementary nutrient feed used to extend the productive phase of fermentation. this increases yield by maintaining little or no growth but supplying enough nutrient to keep the cells alive and fuel antibiotic biosyntheisis. can increase antibiotic conc in reactor by 2-20 folds

Question 7

requirements of the fermenter

Answer 7

adequate mixing to ensure uniform biomass & nutrients
oxygen transfer to the liquid phase
shear levels that don’t tear cells apart
temp control

Question 8

design parameters

Answer 8

reactor dimensions, turbine design & number, baffle design & number, sparger design

Question 9

stirrer speed

Answer 9

at higher stirrer rate, we get smaller bubbles & adequate mixing