Bioprocess Engineering and Process Biotechnology MCQs

For scaling up for a bioreactor, the following parameter is assumed to be constant

Which of the following events occur during the stationary phase of bacterial growth? P. Rise in cell number stops. Q. Spore formation in some Gram-positive bacteria such as Bacillus subtilis. R. Cell size increases in some Gram-negative bacteria such as Escherichia coli. S. Growth rate of bacterial cells nearly equals their death rate. T. Decrease in peptidoglycan cross-linking.

In a batch culture of Penicillium chrysogenum, the maximum penicillin synthesis occurs during the

Biomass is being produced in a continuous stirred tank bioreactor of 750 L capacity. The sterile feed containing 8 g L-1 glucose as substrate was fed at a flow rate of 150 L h-1. The microbial system follows Monod's model with μm = 0.4 h-1, KS = 1.5 g L-1 and \[{Y_{\frac{X}{S}}}\] = 0.5 g cell mass-g substrate-1. Determine the cell productivity (g L-1 h-1) at steady state.

A bacterial culture with an appropriate biomass composition of CH1.8O0.5N0.2 is grown aerobically on a defined medium containing glucose as the sole carbon source and ammonia being the nitrogen source. In this fermentation, biomass is formed with a yield coefficient of 0.35 gram dry cell weight per gram of glucose and acetate is produced with a yield coefficient of 0.1 gram acetate per gram of glucose. The respiratory coefficient for the above culture will be

Batch fermentation of glucose to ethanol yields a productivity of 4.5 g-1L h-1. If the yeast cell concentration in the fermentation broth is 5% (v/v) and the intracellular NAD+/NADH concentration in the yeast cells is 10 μM, the cycling rate of NAD+ ⇌ NADH will be

A roller bottle culture vessel perfectly cylindrical in shape having inner radius (r) = 10 cm and length (l) = 20 cm was fitted with a spiral film of length (L) = 30 cm and width (W) = 20 cm. If the film can support 105 anchorage dependent cells per cm2, the increase in the surface area after fitting the spiral film and the additional number of cells that can be grown respectively are

A protein binds to phosphocellulose column at pH 7.0 and elutes at pH 8.0. If the protein has to be further purified on a DEAE Sephacel column, the binding buffer should have a pH of

Which one of the following monolayer culture systems have the highest surface area to medium ratio?