A5048089050- Lignin and Wood Chemistry
- Enzyme-mediated dye degradation
- Biochemical and biochemical processes
- Biofuel production and bioconversion
- Plant Gene Expression Analysis
- Fermentation and Sensory Analysis
- Hydrocarbon exploration and reservoir analysis
- Wood Treatment and Properties
- Microbial Metabolism and Applications
- Advanced Cellulose Research Studies
- Petroleum Processing and Analysis
- Cultural Heritage Materials Analysis
- Coal and Its By-products
- Plant Surface Properties and Treatments
- Postharvest Quality and Shelf Life Management
- Microbial Metabolic Engineering and Bioproduction
- Isotope Analysis in Ecology
- Synthesis and Biological Evaluation
- Plant biochemistry and biosynthesis
- Phytochemicals and Antioxidant Activities
- Metal-Catalyzed Oxygenation Mechanisms
- Horticultural and Viticultural Research
- Enzyme Catalysis and Immobilization
- NMR spectroscopy and applications
- Sugarcane Cultivation and Processing
Instituto de Recursos Naturales y Agrobiología de Sevilla
2016-2025
Consejo Superior de Investigaciones Científicas
2010-2020
National Research Council
2006-2014
Universidade Federal da Bahia
2012-2014
Latvian State Institute of Wood Chemistry
2014
Bank of Brazil
2012
Ministério da Ciência e Tecnologia
2012
Centro de Investigaciones Biológicas Margarita Salas
2000-2010
In-Q-Tel
2010
Cardiff University
2010
The structure of the lignin in wheat straw has been investigated by a combination analytical pyrolysis, 2D-NMR, and derivatization followed reductive cleavage (DFRC). It is p-hydroxyphenyl-guaiacyl-syringyl (with an H:G:S ratio 6:64:30) associated with p-coumarates ferulates. 2D-NMR indicated that main substructures present are β-O-4'-ethers (∼~75%), phenylcoumarans (~11%), lower amounts other typical units. A major new finding flavone tricin apparently incorporated into lignins. NMR DFRC...
Lignin changes during plant growth were investigated in a selected Eucalyptus globulus clone. The lignin composition and structure studied situ by new procedure enabling the acquisition of two-dimensional nuclear magnetic resonance (2D-NMR) spectra on wood gels formed NMR tube as well analytical pyrolysis-gas chromatography-mass spectrometry. In addition, milled-wood lignins isolated analyzed 2D-NMR, spectrometry, thioacidolysis. data indicated that p-hydroxyphenyl guaiacyl units are...
Lignin is conventionally defined as being formed by the oxidative polymerization of three main monolignols, p-coumaryl alcohol, coniferyl and sinapyl that are derived from general phenylpropanoid biosynthetic pathway. Many other phenolic compounds also pathway known to perform genuine lignin monomers in many plants, case monolignol ester conjugates, arising truncated biosynthesis or ferulate esters. Recent investigations, however, have indicated beyond canonical pathway, namely flavonoids,...
This work examines the occurrence of native acetylated lignin in a large set vascular plants, including both angiosperms and gymnosperms, by modification so-called Derivatization Followed Reductive Cleavage (DFRC) method. Acetylated units were found milled wood lignins all selected for this study, mono- eudicotyledons, but absent gymnosperms analyzed. In some plants (e.g., abaca, sisal, kenaf, or hornbeam), acetylation occurred at very high extent, exceeding 45% uncondensed (alkyl-aryl ether...
Biofuel production from lignocellulosic material is hampered by biomass recalcitrance towards enzymatic hydrolysis due to the compact architecture of plant cell wall and presence lignin. The purpose this work study ability an industrially available laccase-mediator system modify remove lignin during pretreatment wood (Eucalyptus globulus) feedstock, thus improving saccharification, analyze chemical modifications produced in whole especially recalcitrant moiety. Up 50% removal ground eucalypt...
The structure of the lignin in cortex and pith elephant grass (Pennisetum purpureum) stems was studied both situ isolated milled "wood" lignins by several analytical methods. presence p-coumarate ferulate pith, as well their lignins, revealed pyrolysis tetramethylammonium hydroxide, 2D NMR, indicated that acylates carbohydrates while polymer. NMR showed a predominance alkyl aryl ether (β–O–4′) linkages (82% total interunit linkages), with low amounts "condensed" substructures, such resinols...
The structure of lignins isolated from the herbaceous plants sisal (Agave sisalana), kenaf (Hibiscus cannabinus), abaca (Musa textilis) and curaua (Ananas erectifolius) has been studied upon spectroscopic (2D-NMR) chemical degradative (derivatization followed by reductive cleavage) methods. analyses demonstrate that these is highly remarkable, being extensively acylated at γ-carbon lignin side chain (up to 80% acylation) with acetate and/or p-coumarate groups preferentially over syringyl...
The structural characteristics of the lignin from jute (Corchorus capsularis ) fibers, which are used for high-quality paper pulp production, were studied. content (13.3% Klason lignin) was high compared to other nonwoody bast fibers production. structure characterized by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), 2D-NMR, and thioacidolysis. Upon Py-GC/MS, released predominantly products syringylpropanoid units with S/G ratio being 2.1 a H/G/S composition 2:33:65. 2D-NMR...
Abstract The chemical structure of milled-wood lignins from Eucalyptus globulus , E. nitens maidenii grandis and dunnii was investigated. were characterized by analytical pyrolysis, thioacidolysis, 2D-NMR that confirmed the predominance syringyl over guaiacyl units only showed traces p -hydroxyphenyl units. lignin had highest content. heteronuclear single quantum correlation (HSQC) NMR spectra yielded information about relative abundances inter-unit linkages in whole polymer. All a β-O-4′...
Abstract In situ analysis of lignin by 2D NMR whole plant material was carried out swelling finely ball-milled samples in deuterated dimethylsulfoxide (DMSO- d 6 ) and sonicated so that a gel formed the tube. Solution HSQC spectra different materials representative for hardwood ( Eucalyptus globulus ), softwood Picea abies non-woody plants Agave sisalana are presented here. The show signals corresponding to those main constituents, such as polysaccharides. were assigned comparing with their...
The structure of the isolated milled "wood" lignin from coconut coir has been characterized using different analytical methods, including Py-GC/MS, 2D NMR, DFRC, and thioacidolysis. analyses demonstrated that it is a p-hydroxyphenyl-guaiacyl-syringyl (H-G-S) lignin, with predominance G units (S/G ratio 0.23) considerable amounts associated p-hydroxybenzoates. Two-dimensional NMR indicated main substructures present in this include β-O-4' alkyl aryl ethers followed by phenylcoumarans...
Tricin [5,7-dihydroxy-2-(4-hydroxy-3,5-dimethoxyphenyl)-4H-chromen-4-one], a flavone, was recently established as an authentic monomer in grass lignification that likely functions nucleation site. It is linked onto lignin aryl alkyl ether by radical coupling with monolignols or their acylated analogs. However, the level of tricin incorporates into remains unclear. Herein, three characterization methods: acidolysis; thioacidolysis; and derivatization followed reductive cleavage; were applied...
The composition and structure of lignin in different tissues-phellem (cork), phloem xylem (wood)-of Quercus suber was studied. Whole cell walls their respective isolated milled lignins were analyzed by pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS), two-dimensional nuclear magnetic resonance spectroscopy (2D-NMR) derivatization followed reductive cleavage (DFRC). Different tissues presented varied p-hydroxyphenyl:guaiacyl:syringyl (H:G:S) compositions. Whereas from...