Effect of Macroporous Support Particles on Cell Immobilization, Mass Transfer and Rheology in a Stirred Cultivation of Aspergillus oryzae Using a Swingstir® Mixer

Narges Ghobadi, Chiaki Ogino, Naoto Ohmura

Immobilization of filamentous fungi via bioprocessing is a popular way to avoid mechanical damage to cells while increasing enzymatic activity. Passive immobilization is an efficient because chemical additives are not used during the immobilization process. In this study, passive immobilization of Aspergillus oryzae was performed in a stirred tank via a flexible agitator to improve the oxygen mass transfer and rheology while increasing the enzymatic activity. To elucidate the effect of porous biomass support particles on these factors, two particles with different sizes and populations were tested in separate batch cultivations. Results showed that one of the advantages of fungal immobilization is the prevention of a high rate of glucose consumption during a submerged fermentation process. Decreasing the size of the biomass support particle increased the shear-thinning behaviour of fluid. We also determined the optimal number of particles needed to produce the largest final amounts of immobilized biomass and enzyme activity.

https://dx.doi.org/10.31873/IJEAS.5.10.19