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.
Amoabediny
Ghassem
G
Department of Chemical Engineering, Faculty of Chemical Engineering, School of Engineering, University of Tehran, PO Box 11365-4563, Tehran, Iran. amoabediny@ut.ac.ir
Abbas
Mahdi Pesaran Haji
MP
Büchs
Jochen
J
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