ANTIBIOTICS QUIZ

Steptomyces ramosus

All of these

Steptomyces aureofaciens

Nocardia sulphurea

antibiotic yields are generally higher when cell growth slows

antibiotic yields are generally higher when cells enter the stationary phase

the precursors are often toxic to the cells

All of these

Lactic acid present in the corn steep liquor is utilized at the maximum rate

All of these

Ammonia is liberated in the medium

Growth of mycelia occurs

water

organic solvents

all of these

ether

S. griseoflavus

S. ramosus

S. griseus

S. aerofaciens

Slight rise in pH due to liberation of ammonia

All of these

Autolysis of the medium starts

Concentration of antibiotic increases in the medium

precipitates

solvent phase

aqueous phase

both (a) and (b)

continuous aeration

aeration which does not affect the yield

no aeration

controlled aeration

sugar, CaCO3 and (NH4)2SO4

corn steep liquor, CaCO3 and (NH4)2SO4

sugar, corn steep liquor, CaCO3, (NH4)2SO4 and NH4 Cl

corn steep liquor, CaCO3, (NH4)2SO4 and NH4 Cl

both (a) and (b)

aqueous phase

solvent phase

precipitates