Skip to main content
ARS Home » Midwest Area » Madison, Wisconsin » U.S. Dairy Forage Research Center » Research » Publications at this Location » Publication #213508

Title: GEL-STATE NMR OF BALL-MILLED WHOLE CELL WALLS IN DMSO-d6 USING 2D SOLUTION-STATE NMR SPECTROSCOPY

Author
item KIM, HOON - UNIV OF WISCONSIN
item YELLE, DANIEL - U.S. FOREST PRODUCTS LAB
item AKIYAMA, TAKUYA - UNIV OF TOKYO
item Ralph, John

Submitted to: Symposium Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 3/1/2007
Publication Date: 6/10/2007
Citation: Kim, H., Yelle, D.J., Akiyama, T., Ralph, J. 2007. Gel-state NMR of ball-milled whole cell walls in DMSO-d6 using 2D solution-state NMR spectroscopy. In: Proceedings of 10th International Congress on Biotechnology in the Pulp and Paper Industry, June 10-14, 2007, Madison, Wisconsin. p. 94.

Interpretive Summary:

Technical Abstract: Plant cell walls were used for obtaining 2D solution-state NMR spectra without actual solubilization or structural modification. Ball-milled whole cell walls were swelled directly in the NMR tube with DMSO-d6 where they formed a gel. There are relatively few gel-state NMR studies. Most have involved solid-state NMR spectroscopy which has low resolution and provides little detailed structural information; solution-state NMR studes have usually obtained simple proton or carbon spectra. After overcoming technical difficulties associated with gel-like sample preparation and NMR shimming (since the whole cell walls were negligibly dissolved in DMSO), 2D NMR spectra showed genuine structural information from lignins, celluloses, and other cell wall components. The cellulose signals are relatively depleted, suggesting that the highly crystalline components remain invisible, but the lignins, for example, may be fully represented. Since gel formation in DMSO does not require any other steps, such as dissolving samples in chemicals/solvents, filtering, or drying, and the cell wall does not require any derivatization, this gel-state 2D NMR technique appears to be useful as an independent research tool for rapidly characterizing aspects of the cell wall. It may complement whole cell wall dissolution in DMSO-d6/NMI (where, without perdeuterating NMR, the NMI signals obliterate the aromatic region of the spectrum important for lignins), or the established method of dissolution in DMSO/NMI followed by acetylation with Ac2O which, following precipitation into water, provides acetylated cell wall samples soluble in conventional NMR solvents such as CDCl3 or DMSO-d6. In addition, this method may be useful for efficient pre-screening of necessary cell wall samples before going to the trouble of making derivatized cell wall samples.