Dynamic Simulation and Optimization for Arthrospira platensis Growth and C-phycocyanin Production

This is the accepted manuscript. The final version is available at http://pubs.acs.org/doi/abs/10.1021/acs.iecr.5b03102.C-phycocyanin is a high-value bioproduct synthesized from cyanobacterium Arthrospira platensis. To facilitate its application, advanced dynamic models were built to simulate the complex effects of light intensity, light attenuation and nitrate concentration on cell growth and pigment production in the current research. By comparing these models against the experimental results, their accuracy was verified in both batch and fed-batch processes. Three key findings are presented in this work. First, a noticeable difference between the optimal light intensity for cell growth (282 μmol m-2 s-1) and phycocyanin synthesis (137 μmol m-2 s-1) is identified. Second, light attenuation is demonstrated to be the primary factor causing the decrease of intracellular phycocyanin content instead of nitrate concentration in the fed-batch process, while it has no significant effect on total phycocyanin production. Finally, although high nitrate concentration can enhance cell growth, it is demonstrated to suppress intracellular phycocyanin accumulation in a long-term operation.Author E. A. del Rio-Chanona is funded by CONACyT scholarship No. 522530 and the Secretariat of Public Education and the Mexican government. This work was also supported by the National High Technology Research and Development Program 863, China (No. 2014AA021701) and the National Marine Commonwealth Research Program, China (No. 201205020-2)