CO2 data from eucaryotic fermentation exhaust gas was used to monitor growth state and feed. you should be able to see a trend to reflect the metabolic state of your culture too.

the CO2 exhaust is highly dependent on pH control. In order to validate a steady state, it is necessary to correct raw data of production with the carbonates accumulation.

Dear Cansu,

you may have a look at figure S4 in the supplement of the following publication:

https://www.ncbi.nlm.nih.gov/m/pubmed/24571712/

It shows the steady-state CO2 offgas signal during continuous cultivation of Bacillus subtilis. In most chemostat publications you'll just find values for CTR or CER determined at metabolic steady-state.

Michael

Dear Michael,

Thank you very much. I was expecting to see it constant due to steady state and the reference you suggested shows that.

Dear Jean-Louis,

I was wondering if I would be able to see a constant CO2 offgas during steady state, and it seems like I can.

But, your point is in fact very interesting and valuable as well. I guess, you suggest a carbon balance by using CO2 data and other products?

Dear Charles,

I guess you observed a different level of CO2 production after you change your feed? In theory, one should obtain a different steady state for every particular operating condition. But, again, during a particular steady state, CO2 level should be the same.