Bioprocess Engineering and Process Biotechnology MCQs

Which of the following techniques is best suited for immobilizing an affinity ligand?

Which one of the following can not be a limiting substrate if Monod's growth kinetics is applicable?

During cultivation of microorganisms in a fermenter, various parameters are controlled by appropriate sensor (probe). Match each probe in Group I with the appropriate response mechanism in Group II. Group I (Probe) Group II (Response) P. Thermistor 1. Activation of acid/alkali pump Q. Oxygen electrode 2. Activation of vegetable oil pump R. Metal rod 3. Activation of hot/cold water pump S. pH electrode 4. Increase/decrease in stirrer motor speed

The kinetics of the disintegration of baker's yeast cells in a bead mill is described as $$\frac{{dp}}{{dt}} = K\left( {{P_m} - P} \right)$$ , where P is the concentration of protein released, m is the maximum protein concentration achievable, K is the first order rate constant and is 0.5 h−1 for the system studied. The time required for the release of 90% of the intracellular proteins will be:

A mixture contains three similarly sized peptides P, Q and R. The peptide P is positively charged, Q is weakly negative, and R is strongly negative. If this mixture is passed through an ion-exchange chromatography column containing an anionic resin, their order of elution will be

Match the entries in Group I with the methods of sterilization in Group II. Group I Group II P. Serum 1. Autoclave Q. Luria broth 2. Membrane filtration R. Polypropylene tubes 3. UV irradiation S. Biological safety cabinets 4. Gamma irradiation 5. Dry heat

Match the microbial growth characteristics in Group I with the corresponding features in Group II. Group I Group II P. Growth associated product formation 1. Specific growth rate decreases with increasing product concentration Q. Non-growth associated product formation 2. Specific product formation rate is constant R. Product inhibition 3. Specific product formation rate is proportional to specific growth rate S. Substrate inhibition 4. Specific growth rate decreases with increasing substrate concentration

In a chemostat, evaluate the dilution rate at the cell washout condition by applying Monod's model with the given set of data: \[{\mu _{\max }} = 1\,{h^{ - 1}};{Y_{\frac{X}{S}}} = 0.5\,g\,{g^{ - 1}};{K_S} = 0.2\,g\,{L^{ - 1}};{S_0} = 10\,g\,{L^{ - 1}}\]

Lysine is being produced in a lab-scale reactor by a threonine auxotroph. After 2 weeks of operation it was observed that the concentration of lysine in the reactor was gradually decreasing. Microbiological assays of reactor samples showed absence of contamination and recorded data showed no change in the operating conditions. The most probable reason for decrease in lysine concentration may be attributed to