A5043644263- Plant Surface Properties and Treatments
- Postharvest Quality and Shelf Life Management
- Horticultural and Viticultural Research
- Tree Root and Stability Studies
- Plant Pathogens and Fungal Diseases
- Tree-ring climate responses
- Plant Physiology and Cultivation Studies
- Plant Water Relations and Carbon Dynamics
- Lignin and Wood Chemistry
- Plant Reproductive Biology
- Wood Treatment and Properties
- Plant Molecular Biology Research
- Forest Insect Ecology and Management
- Biological Activity of Diterpenoids and Biflavonoids
- Plant Gene Expression Analysis
- Plant responses to water stress
- Insect and Pesticide Research
- Plant responses to elevated CO2
- Forest ecology and management
- Thermochemical Biomass Conversion Processes
- Phytochemical Studies and Bioactivities
- Pharmacological Effects of Medicinal Plants
- Building materials and conservation
- Conservation Techniques and Studies
- Polysaccharides and Plant Cell Walls
University of Lisbon
2000-2024
Instituto Politécnico de Lisboa
2006-2014
Instituto de Investigação Científica Tropical
2012
Abstract Eucalypt wood ( Eucalyptus globulus ) was heated in an oven for 2–24 h at 170–200°C and autoclave with superheated saturated steam 2–12 190–210°C. The chemical composition of untreated thermally treated different mass losses the range 1.1–11.9% studied by summative analysis, dichloromethane, ethanol water extracts determined gas chromatography spectometry (GC-MS). hemicelluloses degraded first, mainly regarding arabinose xylose moieties. Lignin a slower rate cellulose only slightly...
Suberin in extractive-free potato periderm amounts to approximately 25% determined by NaOCH(3) methanolysis. Monomeric composition is characterized glycerol (20% of monomers), long-chain alpha, omega-diacids, omega-hydroxyacids, alkanoic acids, and alkan-1-ols, with predominance octadec-9-enodioic acid 18-hydroxyoctadec-9-enoic (39 15% monomers, respectively). Aromatic hydroxycinnamyl monomers were also present (<1%). Partial depolymerization suberin using a Ca(OH)(2)-catalyzed methanolysis...
Total depolymerization of cork from the oak (Quercus suber L.) by using a sodium methoxide catalysed methanolysis solubilized 53.2 % material, including 5.2 glycerol, 48,0 suberinic fatty acids and alcohols minor amounts ferulic acid. A very mild calcium oxide treated methanol, which only 2.0% material was studied GC-MS. In total amount aliphatic 43.8 (including alkanoic 4.0%. ω-hydroxyacids 13.2% α,ω-diacids 26.6%), 1-alkanols 2.1 monoacylglycenols 32.1%. It possible to identify...
In the cork oak ( Quercus suber L.), phellogen differentiates during first year of growth in cell layer immediately under epidermis and divides to form 3–6 suberized phellem cells. Division only occurs after suberization previous divided cell. During four years growth, cells have tannin-filled lumens it is 5th 7th that they acquire characteristics ʻadultʼ with empty thin walls. The lenticels are formed by lenticular phellogen, which stomata has a high meristematic activity. this region,...
The quality evaluation of cork planks in relation to porosity may use image analysis techniques. Results are presented on the number, dimensions, form and orientation lenticular channels tangential, transverse radial sections different thickness qualities. coefficient (% pore area total area) varied between 1.1%-18.9% 2,1%-16.4%, respectively tangential transverse/radial is determined mostly by number pores larger than 0.81 mm 2 their average area. be used define classes. Due heterogeneous...
Plant cuticles have been traditionally classified on the basis of their ultrastructure, with certain chemical composition assumptions. However, nature plant cuticle may be misinterpreted in prevailing model, which was established more than 150 years ago. Using adaxial leaf Ficus elastica , a study conducted aim analyzing cuticular and potential relationship between structure chemistry. Gradual extractions diverse analytical microscopic techniques were performed isolated two different stages...
Poly(ω-hydroxyacid) ester oligomers were obtained from the cutin of four plant cuticles by partial depolymerization methanolysis. The structure these was determined electrospray ionization coupled to tandem mass spectrometry (ESI-MS/MS) analysis their lithium-adducts, showing which monomers present and relative position. Dimers up heptamers identified, in a total yield 50% content. Two main structural types poly(ω-hydroxyacid) found. Poly(10,16-dihydroxyhexadecanoic acid) esters Lycopersicum...
Cork oak (Quercus suber) is one of the rare trees with ability to produce cork, a material widely used make wine bottle stoppers, flooring and insulation materials, among many other uses. The molecular mechanisms cork formation are still poorly understood, in great part due difficulty studying species long life-cycle for which there scarce molecular/genomic information. forests ecological importance represent major economic social resource Southern Europe Northern Africa. However, global...
Plants are subjected to adverse conditions being outer protective tissues fundamental their survival. Tree stems enveloped by a periderm made of cork cells, resulting from the activity meristem phellogen. DNA methylation and histone modifications have important roles in regulation plant cell differentiation. However, studies on its involvement differentiation scarce despite importance. Cork oak development was used as model study formation secondary tissues, behavior after traumatic wounding...
Cork samples with an age of 9 years and different growth rates, corresponding to calibre classes 'small', 'medium' 'large', were observed by scanning electron microscopy tested mechanically in compression. Differences correspond widths annual rings; differ because both the number cells produced per year cell dimensions differ. For instance, small large cork had, respectively, 50 151 one row ring, average prism height 32.6 39.8 )µm. The stress-strain curves obtained compression parallel three...
Cork suberin was partially depolymerized by methanolysis catalyzed calcium hydroxide. Analysis GC-MS of the methanolysate showed monomers, including glycerol and long-chain α,ω-diacids ω-hydroxyacids. ESI-MS analysis showed, besides aliphatic oligomers, linear dimeric esters Two types were identified: a α,ω-diacid linked to ω-hydroxyacid two inter-linked The ω-hydroxyacids found as monomer residues in mainly C18 monomers with midchain substituents. identification these based their CID-MS/MS...
Proteins from potato (Solanum tuberosum L.) tuber slices, related to the wound-healing process, were separated by 2-DE and identified an MS analysis in MS/MS mode. Slicing triggered differentiation processes that lead changes metabolism, activation of defence cell-wall reinforcement. storage, cell growth division, structure, signal transduction, energy production, disease/defence mechanisms secondary metabolism detected. Image gels revealed a time-dependent change complexity polypeptide...
The seasonal effect is the most significant external source of variation affecting vascular cambial activity and development newly divided cells, hence wood properties. Here, edapho-climatic conditions on phenotypic molecular plasticity differentiating secondary xylem during a growing season was investigated. Wood-forming tissues maritime pine (Pinus pinaster) were collected from beginning to end in 2003. Data examination fibre morphology, Fourier-transform infrared spectroscopy (FTIR),...