Abstract
Integrating multidisciplinary research in plant genetic engineering and renewable deep eutectic solvents (DESs) can facilitate a sustainable and economic biorefinery. Herein, we leveraged a plant genetic engineering approach to specifically incorporate C6C1 monomers into the lignin structure. By expressing the bacterial ubiC gene in sorghum, p-hydroxybenzoic acid (PB)-rich lignin was incorporated into the plant cell wall while this monomer was completely absent in the lignin of the wild-type (WT) biomass. A DES was synthesized with choline chloride (ChCl) and PB and applied to the pretreatment of the PB-rich mutant biomass for a sustainable biorefinery. The release of fermentable sugars was significantly enhanced (∼190 % increase) compared to untreated biomass by the DES pretreatment. In particular, the glucose released from the pretreated mutant biomass was up to 12 % higher than that from the pretreated WT biomass. Lignin was effectively removed from the biomass with the preservation of more than half of the β-Ο-4 linkages without condensed aromatic structures. Hydrogenolysis of the fractionated lignin was conducted to demonstrate the potential of phenolic compound production. In addition, a simple hydrothermal treatment could selectively extract PB from the same engineered lignin, showing a possible circular biorefinery. These results suggest that the combination of PB-based DES and engineered PB-rich biomass is a promising strategy to achieve a sustainable closed-loop biorefinery.
| Original language | English |
|---|---|
| Pages (from-to) | 5235-5244 |
| Number of pages | 10 |
| Journal | ChemSusChem |
| Volume | 14 |
| Issue number | 23 |
| DOIs | |
| State | Published - Dec 6 2021 |
Funding
This work was supported by the National Science Foundation grant CBET2027125 and the USDA National Institute of Food and Agriculture, McIntire Stennis project 1167926. Oak Ridge National Laboratory is managed by UT-Battelle, LLC under Contract DE-AC05-00OR22725 with the U.S. Department of Energy (DOE). AJR and YP acknowledges the support from the Center for Bioenergy Innovation (CBI), a U.S. DOE Bioenergy Research Center supported by the Office of Biological and Environmental Research in the DOE Office of Science. The views and opinions of the authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. This work was also part of the DOE Joint BioEnergy Institute (http://www.jbei.org) supported by the U. S. Department of Energy, Office of Science, Office of Biological and Environmental Research, through contract DE-AC02-05CH11231 between Lawrence Berkeley National Laboratory and the U.S. Department of Energy. KKH acknowledges the financial support from the Korea Institute of Science and Technology (2E31273).
| Funders | Funder number |
|---|---|
| National Science Foundation | CBET2027125 |
| U.S. Department of Energy | |
| National Institute of Food and Agriculture | 1167926 |
| Office of Science | DE-AC02-05CH11231 |
| Biological and Environmental Research | |
| Oak Ridge National Laboratory | |
| Lawrence Berkeley National Laboratory | |
| Center for Bioenergy Innovation | |
| UT-Battelle | DE-AC05-00OR22725 |
| Korea Institute of Science and Technology | 2E31273 |
Keywords
- biorefinery
- green solvent
- lignin
- lignin depolymerization
- sustainable process
