Five lignin samples were fractionated with Acetone/Water mixtures and the obtained fractions were subjected to extensive structural characterization, including Fourier Transform Infrared (FT-IR), Gel permeation Chromatography (GPC) and Phosphorus-31 NMR spectroscopy (P-NMR). The results showed that for all studied lignins the solubility increases with the increment of the acetone concentration....

Sugar-based biorefineries have faced significant economic challenges. Biorefinery lignins are often classified as low-value products (fuel or low-cost chemical feedstock) mainly due to low lignin purities in the crude material. However, recent research has shown that biorefinery a great chance of being successfully used high-value products, which turn should result an economy renaissance whole ...

BACKGROUND Alkaline hydrogen peroxide pretreatment catalyzed by Cu(II) 2,2'-bipyridine complexes has previously been determined to substantially improve the enzymatic hydrolysis of woody plants including hybrid poplar as a consequence of moderate delignification. In the present work, cell wall morphological and lignin structural changes were characterized for this pretreatment approach to gain ...

A new fast-growing wood raw material, willow (Salix matsudana cv. Zhuliu), was subjected to pulping to identify the structure of its lignin. Thus, the black liquor lignin (AL) and enzymatic mild acidolysis lignin (EMAL) were prepared, and their molecular structure and molecular weight of the isolated lignin polymers were comprehensively investigated by Fourier transform infrared spectroscopy (F...

S1. Comment: Tyramine Ferulates in Tobacco Lignins Tobacco lignins were found to have a substantial component derived from tyramine ferulate. The levels of this component appeared elevated in certain CCRand CAD-deficient transgenics (Ralph et al., 1998). Although we were careful to note that tyramine ferulate is a wellknown wound-response product in tobacco, we remained convinced by the correla...

Aldehyde assisted fractionation of biomass produces an acetal-stabilised lignin that is fully upgradeable. We exploit the aldehyde to control lignin's physical properties, producing lignins can be soluble in both polar and apolar solvents.

In angiosperms, OMTs (EC 2.1.1.6) are bispecific and catalyze the methylation of caffeic acid to ferulic acid and 5hydroxy-ferulic acid to sinapic acid using S-adenosyl-L-Met as methyl donor. The resulting products, ferulic acid and sinapic acid, may subsequently be converted to the corresponding alcohols that are incorporated in lignins. In gymnosperms, where syringyl lignins are absent, OMTs ...

The extracellular fluid of ligninolytic cultures of the wood-decomposing basidiomycete Phanerochaete chrysosporium Burds. contains an enzyme that degrades lignin substructure model compounds as well as spruce and birch lignins. It has a molecular size of 42,000 daltons and requires hydrogen peroxide for activity.