Figure 3. Comparison of Dissolved Oxygen Profiles in Small- and Large-scale Fermentations
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Figures 2 and 3 illustrate a successful scale-down of a microbial fermentation process based on culture growth and dissolved
oxygen profiles, respectively. While the dissolved oxygen profiles in Figure 3 were slightly different, the rates of oxygen
consumption (excluding the fluctuation at t=20 hours) were similar.
SUMMARY
Creation of scale-down models that meet qualification requirements can be challenging, particularly for upstream unit operations.
These models can be of great use when performing experimental studies in an efficient and economical fashion. However, there
are considerations unique to each unit operation that apply during scale-down. It must be mentioned that while scale-down
studies certainly increase the chances of having a successful validation campaign, they only provide guidance. The actual
confirmation must be made at large-scale.
Anurag Rathore, is a principal scientist at Amgen Inc., 30W-2-A, One Amgen Center Drive, Thousand Oaks, CA 91320, 805.447.4491, fax 805.499.5008, arathore@amgen.com
Raj Krishnan
work for Amgen Inc, Thousand Oaks, CA.
Stephanie Tozer
work for Amgen Inc, Thousand Oaks, CA.
Dave Smiley
work for Amgen Inc., Longmont, CO.
Steve Rausch
work for Amgen Inc., Longmont, CO.
Jim Seely work for Amgen Inc., Longmont, CO.
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