A simplified procedure for the identification and measurement of single-ring aromatic products of lignin acidolysis is described. The procedure employed a 6-h hydrolysis of spruce milled wood lignin in acidic dioxane at 87 degrees C, followed by a series of organic extractions to recover acidolysis products which were quantified by gas chromatography of trimethylsilyl derivatives. Complex gel p...

Kraft-AQ pulping lignin was sequentially fractionated by organic solvent extractions and the molecular properties of each fraction were characterized by chemical degradation, GPC, UV, FT-IR, (13)C-NMR and thermal analysis. The average molecular weight and polydispersity of each lignin fraction increased with its hydrogen-bonding capacity (Hildebrand solubility parameter). In addition, the ratio...

The study aims to compare the lignin extraction methods of OPEFB using different solvents; soda and dioxane solvent, reinforcement effects in polylactic acid (PLA) bio-composite. Different method has been found produce with properties purity. yield also highly dependent on types solvents used process. Soda treatment had shown a good removal 17.4 % yield, but only 8.08 for treatment. In contrast...

Ball-milled bamboo (Neosinocalamus affinis) was first treated under ultrasound at 20 C in 95% ethanol solution for 0 to 50 min, dissolved in sodium hydroxide/urea solution (7% NaOH/12% urea) at –12 C, and then extracted with ethanol and dioxane to isolate lignin. The structure of the isolated lignin was characterized with a set of wet chemical and spectroscopic methods, including UV, FT-IR, C N...

This research was caried out to understand the behavior of growth regulators (giberelic acid (GA3) e 6-benzilaminopurin (BAP) on lignification system of Eucalyptus grandis (FORMER Hill Maiden). After GA3 (alone) and BAP (combined) applications, analyses were carried out. These regulators were applied by a atomization system at different concentrations levels. Anatomical analysis, including Mäul...

The aim of the present work is to obtain a chemical-mechanical pulp (CMP) from poplar wood with improved properties, to be used in packing papers in place of more expensive softwood or hardwood pulp. For improving the CMP quality indicators, a preliminary treatment of the pulp has been carried out with a mixture of oxidizing enzymes produced from Phanerochaete chrysosporium, including lignin pe...

The structure of the lignin from brewer's spent grain (BSG) has been studied in detail. Three different lignin preparations, the so-called "milled-wood" lignin (MWL), dioxane lignin (DL), and cellulolytic lignin (CEL), were isolated from BSG and then thoroughly characterized by pyrolysis GC/MS, 2D-NMR, and derivatization followed by reductive cleavage (DFRC). The data indicated that BSG lignin ...

Lignocellulosic biomass (Moso Bamboo, Chinese tallow tree wood, switchgrass, and pine wood) was subjected to a novel delignification process using microwave energy in a binary glycerol/methanol solvent. The physicochemical properties of the recovered lignin were analyzed prior to its application in the fabrication of polylactic acid (PLA)–lignin composites. The results showed that the samples h...

Background: Cellulase adsorption to lignin is considered a cost barrier for bioethanol production; however, its detailed association mechanism is still not fully understood. In this study, two natural poplar variants with high and low sugar release performance were selected as the low and high recalcitrant raw materials (named L and H, respectively). Three different lignin fractions were extrac...

The effect of horseradish peroxidase/H(2)O(2) in organic medium (dioxane/aqueous buffer, pH 5, 95:5) on the depolymerization of synthetic (dehydrogenatively polymerized) lignin was reinvestigated. In contrast to previous claims [Dordick, J. S., Marletta, M. A. & Klibanov, A. M. (1986) Proc. Natl. Acad. Sci. USA 83, 6255-6257], our results demonstrated that vigorous depolymerization of this subs...