Biomedical Engineering Reference
In-Depth Information
7.
Biotechnol Prog
. 2010 Jul-Aug;
26(4):1200-3. Use of disposable
reactors to generate inoculum
cultures for
E. coli
production
fermentations. Mahajan E,
Matthews T, Hamilton R, Laird
MW. Process Development
Engineering, Genentech, Inc.,
South San Francisco, CA.
Disposable technology is being used more each year
in the biotechnology industry. Disposable bioreactors
allow one to avoid expenses associated with
cleaning, assembly, and operations, as well as
equipment validation. The Wave Bioreactor is well
established for Chinese Hamster Ovary (CHO)
production; however, it has not yet been thoroughly
tested for
E. coli
production because of the high
oxygen demand and temperature maintenance
requirements of that platform. The objective of this
study is to establish a robust process to generate
inoculum for
E. coli
production fermentations in a
Wave Bioreactor. We opted not to evaluate the WAVE
system for production cultures because of the high
cell densities required in our current
E. coli
production processes. Instead, the Wave Bioreactor
20/50 system was evaluated at laboratory scale (10
L) to generate inoculum with target optical densities
(OD(550)) of 15 within 7-9 h (preestablished target
for stainless steel fermentors). The maximum settings
for rock rate (40 rpm) and angle (10.5) were used to
maximize mass transfer. The gas feed was also
supplemented with additional oxygen to meet the
high respiratory demand of the culture. The results
showed that the growth profiles for the inoculum
cultures were similar to those obtained from
conventional stainless steel fermentors. These
inoculum cultures were subsequently inoculated into
10 L working volume stainless steel fermentors to
evaluate the inocula performance of two different
production systems during recombinant protein
production. The results of these production cultures
using WAVE inocula showed that the growth and
recombinant protein production was comparable to
the control data set. Furthermore, an economic
analysis showed that the WAVE system would
require less capital investment for installation, and
operating expenses would be less than traditional
stainless steel systems.
