Exploration of the Out-of-Phase Phenomenon in Shake Flasks by CFD Calculations of Volumetric Power Input, ka Value and Shear Rate at Elevated Viscosity.

Culture broth with secreted macromolecules and culture broth of filamentous fungi showing disperse growth exhibit elevated viscosity, usually with shear-thinning flow behavior. High viscosity, however, poses a serious challenge in the production and research of these compounds and organisms. It commonly causes insufficient mixing and oxygen transfer in large- and small-scale bioreactors.

Validation of computational fluid dynamics of shake flask experiments at moderate viscosity by liquid distributions and volumetric power inputs.

Computational fluid dynamics (CFD) has recently become a pivotal tool in the design and scale-up of bioprocesses. While CFD has been extensively utilized for stirred tank reactors (STRs), there exists a relatively limited body of literature focusing on CFD applications for shake flasks, almost exclusively concentrated on fluids at waterlike viscosity. The importance of CFD model validation cannot be overstated.

Black glucose-releasing silicon elastomer rings for fed-batch operation allow measurement of the oxygen transfer rate from the top and optical signals from the bottom for each well of a microtiter plate.

Background: In industrial microbial biotechnology, fed-batch processes are frequently used to avoid undesirable biological phenomena, such as substrate inhibition or overflow metabolism. For targeted process development, fed-batch options for small scale and high throughput are needed. One commercially available fed-batch fermentation system is the FeedPlate, a microtiter plate (MTP) with a polymer-based controlled release system.