Regime analysis and scale-down: Tools to investigate the performance of bioreactors

Mixing in the Fermentation and Cell Culture Industries

“…Besides regime analysis, it is also important to use dimensional analysis and the principles of similarity to devise small scale experiments (Sweere et al, 1987). The use of regime analysis in conjunction with scaled-down optimization techniques has been reviewed by Sweere et al (1987). Regime analysis of baker's yeast and B. subtilis fermentations can be found in Sweere et al (1987) and Amanullah (1994).…”

“…The use of regime analysis in conjunction with scaled-down optimization techniques has been reviewed by Sweere et al (1987). Regime analysis of baker's yeast and B. subtilis fermentations can be found in Sweere et al (1987) and Amanullah (1994). Oosterhuis (1984) conducted a regime analysis for the gluconic acid fermentation in a 25 m 3 fermenter.…”

“…It can also be used to determine whether there is a single rate-limiting mechanism (pure regime) or whether more than one mechanism (mixed regime) is responsible. Besides regime analysis, it is also important to use dimensional analysis and the principles of similarity to devise small scale experiments (Sweere et al, 1987). The use of regime analysis in conjunction with scaled-down optimization techniques has been reviewed by Sweere et al (1987).…”

Ultra scaledown to predict filtering centrifugation of secreted antibody fragments from fungal broth

“…In terms of solid±liquid separation, most traditional laboratory devices are not amenable to scale-up. In cases in which this has been attempted problems occur because pilot-and full-scale plant units generally do not perform as well as conventional laboratory-scale systems (Atkinson and Mavituna, 1991;Reisman, 1993;Sweere et al, 1987). The alternative is to use either scaledown or ultra scaledown techniques, both of which are aimed at creating full-scale process conditions at the laboratory scale.…”

Scale-down of CHO cell fed-batch cultures

“…Mixing time (Tm= time to reach 95% homogeneity after a local change) is used to evaluate the mixing characteristics of a bioprocess 185,210 . Tm tends to be longer in large-scale bioreactors than in small-scale bioreactors 22,207 , meaning that in larger bioreactors a cell travels through regions with different environments (gradients of pH, DO, nutrient concentration, etc.)…”