Continuous production of the microbial polysaccharide Xanthan gum was studied at steady state conditions over a wide range of parameters. The specific rate of polymer production was found to pass through a maximum with varying dilution rate in a steady state chemostat. The optimal rate is nearly double than that in a batch and transient growth. Glucose consumption for maintentance of the cells show inverse trend to that of polymer production. A novel research method, the use of a bioluminescence as biosensor for metabolic activity, was employed in this work. Besides polymer production, the cloned bioluminescent Xanthomonas campestris was used for mass transfer rate studies. Oxygen and nutrient mass transfer coefficients were determined by analysis of the luminescence response to induced fluctuations in their concentration. Mass transfer coefficients were correlated with hydrodynamic parameters.
- Mass transfer