NEW BRUNSWICK SCIENTIFIC BioFlo CelliGen 115, Руководство по эксплуатации

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BioFlo/CelliGen 115
y
M1369-0050 User’s Guide
Glucose feeding can be set to respond to other sensor cues (such as DO level, the pH
reading, the turbidity measurement, the glucose measurement, etc.). The pumping
profile to be used must generally be determined through experimental experience.
21.6 Recommended Process Control Settings
Question: What are the recommended process control settings (i.e., temperature,
pH, agitation speed, DO & gas sparge rate)?
Answer:
For
E. coli,
temperature is usually set to 32° - 35°C and pH is set at 7.0 - 7.2.
For yeast the values are 30°C and a pH value of 5.0. Agitation speed is usually set to a
minimum of 200 - 300 rpm with a maximum value of 1000 rpm. Dissolved oxygen
(or DO) level is usually 30%. The gas sparge rate is generally 0.5 to 1.0 VVM.
21.7 Typical Fermentation Run
Question: Can you review the steps involved in set-up through shutdown of a
fermentation run?
Answer:
To answer properly, let's break the process down, as follows:
21.7.1 Vessel Preparation Before Autoclaving
It is advisable to rinse the previously cleaned vessel prior to use. When doing
this, remember that all clamps must be open and the valve for the sampling
tube must be in the open position. If the glass wool is going to be replaced for
the run, then remove it (and the rubber sampler bulb) prior to rinsing. The
protective bearing housing cap must also be in place. It will be necessary to
hold the protective cap in place if you plan to invert the headplate while rinsing
it. In this case it is usually advisable to also remove the clamps that hold the
headplate onto the rest of the vessel, as failure to do so will result in their
falling out during inversion. The pH and DO probes should not be in the
headplate while you rinse it. All gas filters must be removed prior to rinsing.
The sparger must, in particular, be checked to ensure that it isn't clogged.
The headplate must be oriented in combination with the vessel and the internal
baffle so as to allow for the exhaust condenser lines to be connected. Also, the
baffle must be positioned so that it does not interfere with the insertion of the
pH and DO probes into their ports. Do
not
place the sample port to the rear of
the vessel, and position it so that ample room is available to take a sample. It is
advantageous to have the addition ports for acid, base, etc., on the same side as
(or at least
not
opposite) the pumps. The old grease on the top of the glass
cylinder should be wiped clean. Reapply grease (Dow Corning silicone
grease) prior to installing the headplate: smear a very thin
layer around the top