Achieving High Productivity of 2-Pyrone-4,6-dicarboxylic acid (PDC) from Aqueous Aromatic Streams with Novosphingobium aromaticivorans
Authors:
Bumkyu Kim1,2,3* ([email protected]), Jose M. Perez1,2,3, Steven D. Karlen2,3, Jason Coplien2,3, Daniel R. Noguera1,2,3, Timothy J. Donohue2,3,4
Institutions:
1Department of Civil and Environmental Engineering, University of Wisconsin–Madison; 2Wisconsin Energy Institute, University of Wisconsin–Madison; 3Great Lakes Bioenergy Research Center, University of Wisconsin–Madison; 4Department of Bacteriology, University of Wisconsin–Madison
Goals
Evaluate bioreactor conditions to improve the production of 2-pyrone-4, 6-dicarboxylic acid (PDC) from plant-derived aromatics using Novosphingobium aromaticivorans.
Abstract
Researchers found that the accumulation of intermediate compounds such as protocatechuic acid (PCA) and 3-O-methylgallate (3-MGA) is the major factor for the system failure. As such, the team determined that operational conditions that prevented protocatechuic acid (PCA) accumulation during aromatic metabolism improved bioreactor performance. In addition, researchers found that the accumulation of sodium (Na+) by the addition of sodium hydroxide (NaOH) for maintaining pH-base inhibits the growth and PDC production of Novosphingobium aromaticivorans and found that ammonium (NH4+) has less inhibitory effect than Na+. PDC productivity increased when using ammonium hydroxide (NH4OH) instead of NaOH for pH control. Productivity was also increased when the hydraulic retention time in the reactor was reduced to 4 hours. At the best operational condition, a stable PDC production of 1.8 gPDC/L/hr was obtained, which is higher than the highest PDC productivity that has been reported, albeit with a lower product titer as 42 mM (7.9 g/L). Overall, the team’s findings demonstrate that the use of a membrane bioreactor with optimizing strategies can significantly enhance the productivity of PDC from plant-derived aromatics. This approach can be applied for production of other valuable chemicals from lignin and additional feedstocks to reduce the selling price of products, thereby contributing to the commercialization of lignocellulose and other renewal materials.
Funding Information
This material is based upon work supported by the Great Lakes Bioenergy Research Center, DOE, Office of Science, BER program under award number DE-SC0018409.