The Experts below are selected from a list of 2040 Experts worldwide ranked by ideXlab platform
Juan Ignacio Valdez-hernández - One of the best experts on this subject based on the ideXlab platform.
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Wood variation in Laguncularia racemosa and its effect on fibre quality
Wood Science and Technology, 2004Co-Authors: Laura Yáñez-espinosa, Teresa Terrazas, Lauro López-mata, Juan Ignacio Valdez-hernándezAbstract:Laguncularia racemosa wood is commonly used in north-western Mexico and harvested without the knowledge of whether environmental conditions affect wood quality. Laguncularia racemosa anatomy variation was evaluated to identify which cell features, mainly fibre features, are related to an environmental gradient and how this variation affects wood quality. Trees were sampled in six sites along the river where different flooding periods and levels occur. Analyses revealed that in sites with high salinity and flooding levels, there are more abundant vessels and axial parenchyma although the fibres and vessel elements are shorter, suggesting a water stress effect. Correlation analysis confirmed that the higher the percentage of gelatinous fibres, the longer the fibres. This occurred in L. racemosa trees growing in those sites with a high sand particle percentage and a lower flooding level. Anova (analysis of variance) revealed non-significant differences among sites for flexibility, rigidity and Peteri coefficients as well as for Runkel ratio, however the rigidity coefficient is affected by occurrence of gelatinous fibres. L. racemosa wood harvesting should avoid those sites with high flooding level, high sand particle percentage and high salinity that may modify wood quality.
Abdessamad Debbab - One of the best experts on this subject based on the ideXlab platform.
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unusual octalactones from corynespora cassiicola an endophyte of Laguncularia racemosa
ChemInform, 2014Co-Authors: Weaam Ebrahim, Amal H Aly, Victor Wray, Peter Proksch, Abdessamad DebbabAbstract:Five new secondary metabolites with unusual octalactone structure are isolated from the mangrove-derived endophyte Corynespora cassiicola, isolated from Laguncularia racemosa (Combretaceae).
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unusual octalactones from corynespora cassiicola an endophyte of Laguncularia racemosa
Tetrahedron Letters, 2013Co-Authors: Weaam Ebrahim, Amal H Aly, Victor Wray, Peter Proksch, Abdessamad DebbabAbstract:Abstract Chemical investigation of the EtOAc extract of the mangrove-derived endophyte Corynespora cassiicola , isolated from Laguncularia racemosa (Combretaceae), afforded five new secondary metabolites, named coryoctalactones A–E ( 1 – 5 ). The structures of the new compounds were determined on the basis of 1D- and 2D-NMR spectroscopy as well as high-resolution mass spectrometry. The absolute configuration of the side chain in 1 – 3 and 5 were tentatively deduced based on biogenetic consideration in comparison with xestodecalactones, previously isolated from C. cassiicola . All isolated compounds were evaluated for their antimicrobial, cytotoxic, and antitrypanosomal activities.
Laura Yáñez-espinosa - One of the best experts on this subject based on the ideXlab platform.
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Wood variation in Laguncularia racemosa and its effect on fibre quality
Wood Science and Technology, 2004Co-Authors: Laura Yáñez-espinosa, Teresa Terrazas, Lauro López-mata, Juan Ignacio Valdez-hernándezAbstract:Laguncularia racemosa wood is commonly used in north-western Mexico and harvested without the knowledge of whether environmental conditions affect wood quality. Laguncularia racemosa anatomy variation was evaluated to identify which cell features, mainly fibre features, are related to an environmental gradient and how this variation affects wood quality. Trees were sampled in six sites along the river where different flooding periods and levels occur. Analyses revealed that in sites with high salinity and flooding levels, there are more abundant vessels and axial parenchyma although the fibres and vessel elements are shorter, suggesting a water stress effect. Correlation analysis confirmed that the higher the percentage of gelatinous fibres, the longer the fibres. This occurred in L. racemosa trees growing in those sites with a high sand particle percentage and a lower flooding level. Anova (analysis of variance) revealed non-significant differences among sites for flexibility, rigidity and Peteri coefficients as well as for Runkel ratio, however the rigidity coefficient is affected by occurrence of gelatinous fibres. L. racemosa wood harvesting should avoid those sites with high flooding level, high sand particle percentage and high salinity that may modify wood quality.
Weaam Ebrahim - One of the best experts on this subject based on the ideXlab platform.
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unusual octalactones from corynespora cassiicola an endophyte of Laguncularia racemosa
ChemInform, 2014Co-Authors: Weaam Ebrahim, Amal H Aly, Victor Wray, Peter Proksch, Abdessamad DebbabAbstract:Five new secondary metabolites with unusual octalactone structure are isolated from the mangrove-derived endophyte Corynespora cassiicola, isolated from Laguncularia racemosa (Combretaceae).
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unusual octalactones from corynespora cassiicola an endophyte of Laguncularia racemosa
Tetrahedron Letters, 2013Co-Authors: Weaam Ebrahim, Amal H Aly, Victor Wray, Peter Proksch, Abdessamad DebbabAbstract:Abstract Chemical investigation of the EtOAc extract of the mangrove-derived endophyte Corynespora cassiicola , isolated from Laguncularia racemosa (Combretaceae), afforded five new secondary metabolites, named coryoctalactones A–E ( 1 – 5 ). The structures of the new compounds were determined on the basis of 1D- and 2D-NMR spectroscopy as well as high-resolution mass spectrometry. The absolute configuration of the side chain in 1 – 3 and 5 were tentatively deduced based on biogenetic consideration in comparison with xestodecalactones, previously isolated from C. cassiicola . All isolated compounds were evaluated for their antimicrobial, cytotoxic, and antitrypanosomal activities.
Gladys León De Pinto - One of the best experts on this subject based on the ideXlab platform.
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influencia del flujo de la marea y la salinidad en la produccion de la goma del mangle blanco Laguncularia racemosa
Boletín del Centro de Investigaciones Biológicas, 2000Co-Authors: Antonio Vera, Maritza Martínez, Flora Barboza, Delida Acosta, Gladys León De PintoAbstract:Se evaluo la produccion de goma del mangle blanco (Laguncularia racemosa) en dos zonas con desigual flujo de la marea en el manglar de cano El Bongo, cienaga La Tigra, municipio Mara, estado Zulia. El estudio se llevo a cabo durante siete semanas consecutivas en el periodo de sequia (Mayo-Julio, 1997), trazando una transecta de cien metros de longitud en cada una de las zonas. Se practicaron heridas en surco, a nivel del tronco, en individuos con diametro a la altura de pecho, entre 65-190 cm. La mayor produccion del exudado gomoso tiene lugar bajo flujo y reflujo regular de la marea (P
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The molecular characterization of the polysaccharide gum from Laguncularia racemosa
Carbohydrate Polymers, 1998Co-Authors: Gladys León De Pinto, Maritza Martínez, Omaira Gutiérrez De Gotera, Edgar Ocando, Carlos RivasAbstract:Abstract A polysaccharide isolated from the exudate of Laguncularia racemosa , (Combreta-ceae) has been investigated using Smith-degradation, methylation analysis, hydrolysis, and 13 C-NMR spectroscopy. The backbone of the structure is constituted of uronic acids, galactose and rhamnose. A complex pentasaccharide, constituted of these sugars, was isolated from the original gum and degradation products. This oligosaccharide is, probably, the main structural feature of the investigated polysaccharide. On the other hand, according to chemical and spectral evidence rhamnose is present, predominantly as internal residues. Arabinosyl (pyranosyl and furanosyl) residues and some galactosyl, glucuronic acid and 4-0-methyl-α-D-glucuronic acid residues are located in branches.
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Gum polysaccharides of nine specimens of Laguncularia racemosa
Biochemical Systematics and Ecology, 1993Co-Authors: Gladys León De Pinto, Miguel Nava, Maritza Martínez, Carlos RivasAbstract:Gum exudates from nine specimens of Laguncularia racemosa (Combretaceae) from Venezuela were examined. The constituent sugars found were galactose, arabinose, rhamnose, galacturonic acid, glucuronic acid and its 4-O-methyl ether. The results obtained are similar to those in many Combretum gums studied; giving acidic solutions, their nitrogen content tends to be low and their rhamnose content, after acidic hydrolysis, tends to be high. The gum, in deuterium oxide, shows a well resolved 13CNMR spectrum.
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exudado gomoso de Laguncularia racemosa mangle blanco como medio de cultivo para hongos
Investigacion Clinica, 1993Co-Authors: Luz Mila Mesa, Gladys León De PintoAbstract:Se realizaron estudios morfologicos de las siguientes especies de hongos: Aspergillus flavus, Microsporum cunis, Epidermophyton floccoslim, Curvularia lunata, Cladosporium carrionii, Nattrassia mangifera (Edo. Scytalidium), Sporothrix schenckii y Rhizopus oligosporus, pertenecientes a las familias Mucedinaceae. Dematiaceae y Mucoraceae, en un medio preparado con el exudado gomoso de Laguncularia racemosa (mangle blanco). Este polimero nativo esta constituido por galactosa, arabinosa, ramnosa, acidos uronicos y proteinas y presenta corno micronutrientes nitrogeno, calcio y magnesio. La busqueda de un medio de cultivo economico fue el criterio para la evaluacion de un medio preparado con exudado gomoso (4%) y agar 0,5%). Los resultados obtenidos demostraron que el exudado gomoso agar (EGA) permite la identificacion adecuada de las especies estudiadas y puede ser sustituto del medio Sabouraud, ya que la preparacion del mismo se basa en un producto natural nativo, de facil obtencion y economico.
