Influence of oxygen transfer and uptake rates on dihydroxyacetone production from glycerol by Gluconobacter oxydans in resting cells operation

Kinetic Modeling of Dihydroxyacetone Production from Glycerol by Gluconobacter oxydans ATCC 621 Resting Cells: Effect of Fluid Dynamics Conditions

“…However, none of the previously described kinetic models consider the oxygen availability. The importance of oxygen transfer rate in aerobic the bioprocess has already been pointed out in many works [16,[25][26][27][28]. Recently, several authors have put their effort on describing the influence of oxygen transfer rate on DHA production.…”

“…The most widely employed microorganism to produce DHA from glycerol as raw material is Gluconobacter oxydans, although there are several different works using other microorganisms [5][6][7][8][9][10][11][12][13][14][15][16]. G. oxydans is a Gram-negative aerobic bacterium, whose respiratory metabolism allows it to partially oxidize different organic compounds [17].…”

“…This provides G. oxydans with the ability to transform glycerol into DHA rapidly and efficiently. However, as the whole process is intimately associated to the oxygen caption, and this compound is the final donor of electrons in this process, it is crucial to evaluate the influence of oxygen transport from air to the culture media and to the membrane of the microorganism [16].…”

“…Regarding the strain employed in this work, previously published results [16] have shown that there is a need to establish a minimum oxygen transfer rate in order to ensure the highest culture activity. Thus, we can avoid the decrease of DHA production rate due to the oxygen transfer rate (OTR) limitation and its control over the overall process rate [16].…”

“…In order to achieve this objective, several experiments were carried out both in Erlenmeyer flasks and STBR, varying the agitation speed. Operating conditions were fixed, taking into account the results achieved in previous works [15,16]. Throughout the study, resting cells were employed in operation mode.…”