Bioprocess Engineering and Process Biotechnology MCQs

A culture vessel in which physical, physicochemical and physiological conditions, as well as cell concentration, are kept constant is known as

Inversion of sucrose by immobilized invertase follows a substrate inhibited kinetics. The reaction rate (v) in mol m-3 h-1 can be expressed as: $$v = \frac{{800[S]}}{{\left\{ {400 + 50[S] + {{[S]}^2}} \right\}}};$$ where [S] is the sucrose concentration. The immobilized invertase preparation is used in a CSTR with 100 mol m-3 sucrose concentration in the feed stream. If the reaction velocity passes through a maximum at [S] = 20 mol m-3 the feed flow rate for a reactor volume of 1 m3 to get the maximum productivity from the reactor should be

A bioreactor is scaled up based on equal impeller tip speed. Consider the following parameters for small and large bioreactors: Parameters Small bioreactor Large bioreactor Impeller speed N1 N2 Diameter of impeller D1 D2 Power consumption P1 P2 Assuming geometrical similarity and the bioreactors are operated in turbulent regime, what will be $$\frac{{{P_2}}}{{{P_1}}}$$ ?

How many kilograms of ethanol is produced from 1 kilogram of glucose in ethanol fermentation?

Match the bioreactor components in Group I with the most appropriate function given in Group II. Group I Group II P. Marine type impeller 1. Recirculation of medium Q. Draft tube 2. Aeration of medium R. Diaphragm valve 3. Animal cell cultivation S. Sparger 4. Sterile operation

Immobilization of enzymes P. Increases the specificity of the enzyme for its reactants. Q. Facilitates reuse of the enzyme in batch reactions. R. Makes it unsuitable for its use in a continuous reactor system. S. Decreases the operational cost of the industrial process.

A bacterial culture having a specific oxygen uptake rate of 5 mmol O2 (g DCW)-1 hr-1 is being grown aerobically in a fed-batch bioreactor. The maximum value of the volumetric oxygen transfer coefficient is 0.18 s-1 for the stirred tank bioreactor and the critical dissolved oxygen concentration is 20% of the saturation concentration (8 mg mL-1). The maximum density to which the cells can be grown in the fed-batch process without the growth being limited by oxygen transfer, is approximately

The limiting factor in the production of large quantities of ethanol as biofuel is

If the fractional recovery at each step of unit operation is 0.8, the recovery after 4 steps will be