High-Density Animal Cell Culture by Gas Sparging

In order to enhance the oxygen supply for an animal cell culture, several foam-suppressing methods which enable direct gas sparging into culture medium were investigated. When an anti-foaming reagent was added to the medium to suppress foaming, the amount of reagent needed to be controlled in accordance with the aeration rate. With sparger optimization, increasing the sparger pore size reduced the remaining foam time. However, with the sparger pore size larger than certain value, the remaining foam time became constant, and this pore size can be regarded as the optimum. A defoaming device with a hydrophobic net has also been developed, and a culture system equipped with this defoaming net was constructed. A series of culture experiments was performed to confirm the efficacy of the defoaming net, and enhanced cell density and productivity were confirmed.