Determination of CO₂ sensitivity of micro-organisms in shaken bioreactors. II. Novel online monitoring method.
In the present study, a new online monitoring method for the determination of the CO₂ sensitivity of micro-organisms, based on the values of the respiration factors [OTR (oxygen transfer rate) and CTR (carbon dioxide transfer rate)], obtained by using the RAMOS (respiratory activity monitoring system) device considering a variety of aeration rates in the measuring flask, is investigated. Based on the data of the OTR, obtained by RAMOS under a variety of specific aeration rates, the proposed new method was developed as an online monitoring method for CO₂ sensitivity of micro-organisms in shaken bioreactors. A maximum accumulated CO₂ concentration of 12% was derived in applied methods, provided that the cultivation system is carried out under optimal conditions. Additionally, to predict these conditions, an unsteady-state gas transfer model in shaken bioreactors would be very advantageous. The data of OTR obtained using the RAMOS device were analysed and recalculated by a programme considering the calibration factor (Cf). The major advantage of the new method is the possibility to determine the metabolic activity, regardless of manual sampling.
Department of Chemical Engineering, Faculty of Chemical Engineering, School of Engineering, University of Tehran, PO Box 11365-4563, Tehran, Iran. amoabediny@ut.ac.ir
Ghassem
G
Amoabediny
Mahdi Pesaran Haji
MP
Abbas
Jochen
J
Büchs
D019149:Bioreactors / Q000382:microbiology*; D002245:Carbon Dioxide / Q000032:analysis / Q000378:metabolism*; D048230:Corynebacterium glutamicum / Q000254:growth & development / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D010100:Oxygen / Q000378:metabolism*; D010313:Partial Pressure; D010843:Pichia / Q000254:growth & development / Q000378:metabolism; D015203:Reproducibility of Results; D004718:Saccharomycetales / Q000254:growth & development / Q000378:metabolism
D002245:Carbon Dioxide; D010100:Oxygen