Study on volumetric oxygen transfer coefficient of the simulated plant cell two-phase culture system

The effects of the volumetric percentage of simulated plant cells, organic solvents, agitation speeds and aeration rates on the volumetric oxygen tran sfer coefficient, K(L)a, were studied in the simulated plant cell two-phase culture system. The experimental results showed that KLa increased as the Volumetric percentage of organic solvents, H, increased, but this effect be came less significant at high values of H. When the volumetric percentage o f simulated plant cells, E, was higher than 30 %, the effects of H on KLa b ecame less appreciable. In comparison with a one-phase culture system, KLa was higher in the two-phase culture system and can be regulated more easily to suit the cell growth and the production of secondary metabolites. Combi ning with the rheological properties of the system, it was found that the e ffects of E on KLa were very similar to that of E on the now behavior index , n, in the system. An experiential correlation of K(L)a of the system (wit h oleic acid as organic solvent) was obtained as K(L)a = 0.21N(0.91)Q(0.90) exp(4.1H-4.3E) (herein N is the stirring speed and Q, the aeration rate), w hich may be useful for the design of the two-phase culture system.