Fig. 14

2D ssNMR unveils the complex structure of natural abundance biomass. a Simulated dipolar curves for CH and CH₂ indicate increased dipolar coupling at greater depths. The initial slice of the pseudo-2D DIPSHIFT experiment on rice cell walls revealed distinct cellulose and xylan signals, with elevated order parameters in dipolar curves for both the wild type and double mutant of interior cellulose carbon 6 (i6). Panel adapted with permission of ref [47]. b Narrow line shaped in ¹H shows cellulose increased mobility in acid-treated poplar. Panel adapted with permission of ref [175]. c Utilize 2D WISE to elucidate the relationship between crystalline and amorphous cellulose domains and the associated water pool. Panel adapted with permission of ref [176]. d Identification of functional groups in enzymatic hydrolyzed corn stover using ¹H–¹³C FSLG HETCOR without spin diffusion. Panel adapted with permission of ref [144]. e Interactions between archeological wood and consolidant (Kauramin) [177]. f At 300 °C, the acetate groups in lignin and hemicelluloses exhibit incomplete conversion, attributed to the constraints imposed by the macromolecular network present in native Miscanthus. Panel adapted with permission of ref [178]