In the case of submerged cultures, in this case it is concerning organisms immobilized in Ca alginate microspheres, what is the limiting factor, where density of organism in the medium is concerned?
In this case the organism is a fungus with a high oxygen demand, so that is one factor, but O2 is easily suppliable, and fluoroalkanes or fluorinated ethers/aromatics can fulfill a role as oxygen carriers due to the high soluability of gaseous O2 in such solvents.
What I want to know though, is with a given quantity of immobilized mycelia in the liquid medium, is there any good reason it cannot be increased, and the concentraton of nutrients increased also.
What is the limit here? doubled? tripled? or can one go on increasing the concentration until viscosity starts buggering up oxygen transport? the more organism that can be packed into one bioreactor, the better.