132
BioFlo/CelliGen 115
y
M1369-0050
User’s Guide
Open the clamp on the sparger line and visually observe the vessel to ensure
that air is flowing properly. Then set the agitation to the minimum desired
value.
After set-up, the unit should be carefully observed to ensure that there are no
problems, (especially no water line leaks).
21.7.4 Vessel
Operation
The vessel must have any and all necessary addition bottles connected prior to
use. If another bottle, such as the glucose feed, is not initially required, it can
be hooked up later. The pH will probably need to be adjusted. This is done by
setting the pH control to
Auto
. Note that due to the unit’s tendency to
overshoot the target pH during this initial adjustment, it is desirable to set the
initial pH setpoint a little conservatively. (For example: post-sterilization pH
reading is 6.8, and desired setpoint is 7.2. Set the unit to setpoint 7.0 when
conducting the initial adjustment.) Note that the pH reading must be taken
from a vessel that has already cooled down.
Additional media components that are not autoclaved can be added once the
vessel has cooled sufficiently. The protocol for this is the same as for
inoculation, as described below.
Inoculation can be performed by aseptically pouring liquids into the vessel
through the inoculation port, although NBS normally uses the harvest port to
inoculate. A peristaltic pump or gravity is used to introduce the inoculum.
The shake flask is connected to the port terminus using aseptic techniques, and
then the clamps are opened to allow for addition. Once the material is all in
(except for any residual inoculum which must be retained for testing), secure
the clamps and disconnect the shake flask. At this point, the harvest port
terminus must be covered up again, using asceptic techniques, with sterile
cotton and foil.
To harvest from the vessel, attach a line to the harvest port and use a peristaltic
pump to pump the culture broth out.
21.7.5
Vessel Shutdown & Cleaning
When the fermentation run is complete, it is necessary to carefully shut the
process down. First, all operating parameters (agitation, temperature, DO level,
pH, and gas feed) must be set from their current control modes (such as
Auto
,
Manual
, or
ON
) to the
OFF
mode.
