Abstract
Previous studies defined easy and difficult to hydrolyze fractions of hemicellulose that may result from bonds among cellulose, hemicellulose, and lignin. To understand how such bonds affect hydrolysis, Populus trichocarpa×. Populus deltoides, holocellulose isolated from P. trichocarpa×. P. deltoides and birchwood xylan were subjected to hydrothermal flow-through pretreatment. Samples were characterized by glycome profiling, HPLC, and UPLC-MS. Glycome profiling revealed steady fragmentation and removal of glycans from solids during hydrolysis. The extent of polysaccharide fragmentation, hydrolysis rate, and total xylose yield were lowest for P. trichocarpa×. P. deltoides and greatest for birchwood xylan. Comparison of results from P. trichocarpa×. P. deltoides and holocellulose suggested that lignin-carbohydrate complexes reduce hydrolysis rates and limit release of large xylooligomers. Smaller differences between results with holocellulose and birchwood xylan suggest xylan-cellulose hydrogen bonds limited hydrolysis, but to a lesser extent. These findings imply cell wall structure strongly influences hydrolysis.
| Original language | English |
|---|---|
| Pages (from-to) | 202-210 |
| Number of pages | 9 |
| Journal | Bioresource Technology |
| Volume | 179 |
| DOIs | |
| State | Published - Mar 1 2015 |
Funding
We thank the Office of Biological and Environmental Research in the DOE Office of Science for supporting this work through the BioEnergy Science Center (BESC). BESC is a U.S. Department of Energy Bioenergy Research Center supported by the Office of Biological and Environmental Research in the DOE Office of Science . This manuscript has been co-authored by a contractor of the U.S. Government under contract DE-AC05-00OR22725. We acknowledge support by the Ford Motor Company for the Chair in Environmental Engineering at the University of California Riverside that augments our ability to perform such research. HLT thanks the Natural Sciences and Engineering Research Council of Canada for a PGS-D scholarship. The generation of the CCRC series of plant cell wall glycan-directed monoclonal antibodies used in this work was supported by the NSF Plant Genome Program ( DBI-0421683 and IOS-0923992 ). We also wish to thank Seokwon Jung, Georgia Institute of Technology, for preparing the holocellulose used in this study. No sponsor was involved in the study design; in the collection, analysis and interpretation of data; in the writing of the report; or in the decision to submit the article for publication.
Keywords
- Hemicellulose
- Hydrolysis
- Lignin-carbohydrate complex