CENSALUD

Coffee model systems prepared from combinations of chlorogenic acid (CGA), N R -acetyl-1-arginine (A), sucrose (S), and cellulose (C) were roasted at 240°C for 4 min prior to analysis by UV-visible spectrophotometry, capillary zone electrophoresis (CZE), and the ABTS radical cation decolorization assay. The A/CGA/S/C and A/S/C systems were also fractionated by gel filtration chromatography. Antioxidant activity of the systems showed a positive, nonlinear relationship with the amount of CGA remaining after roasting. Sucrose degradation was a major source of color in the heated systems. There was no relationship between antioxidant activity and color generation.

In Morocco, yields of date palms are highly decreased by the pathogen fungi Fusarium oxysporum. To solve this issue, mycorrhizal fungi and biocontrol agents could enhance plant resistance to pathogens. Here, we studied peroxidases in roots and leaves of Phoenix dactylifera in response to inoculation with the fungi Glomus mosseae and Trichoderma harzianum. Date palm plants were harvested 57 weeks after inoculation with mycorrhizal fungi and biocontrol fungi. We measured the dry biomass, arbuscular colonization, cytochemistry of peroxidase, and peroxidase forms and activities in roots and leaves. Our results show that mycorrhization increased the plant dry biomass by about 57%. The rate of mycorrhizal colonization ranged from 25% to 30%. Peroxidase activity in roots colonized by T. harzianum alone was 1.6 times higher than in control plants. Peroxidase activity in roots colonized by G. mosseae and T. harzianum was about 2 times higher than in control plants. Peroxidase activity in leaves increased by + 419% when plants were inoculated by both fungi. The cytochemical results show an accumulation of structural substances in root cell walls after inoculation with T. harzianum. These structural substances may increase the mechanical strength of the host cell walls in order to inhibit pathogen invasion. Peroxidase activities were found in plant cell walls; the tonoplast and host plasmalemma in the chloroplast; mitochondrial membranes; and intercellular spaces of plants inoculated with G. mosseae and T. harzianum. SDS-PAGE analyses of leaf extracts gave a main band at 54 kDa for all the treatments. The stimulatory effect of Trichoderma on the peroxidase activity is a resistance mechanism of date plants to pathogens. The use of Trichoderma could thus be an alternative to chemicals in crop protection.

In Morocco, yields of date palms are highly decreased by the pathogen fungi Fusarium oxysporum. To solve this issue, mycorrhizal fungi and biocontrol agents could enhance plant resistance to pathogens. Here, we studied peroxidases in roots and leaves of Phoenix dactylifera in response to inoculation with the fungi Glomus mosseae and Trichoderma harzianum. Date palm plants were harvested 57 weeks after inoculation with mycorrhizal fungi and biocontrol fungi. We measured the dry biomass, arbuscular colonization, cytochemistry of peroxidase, and peroxidase forms and activities in roots and leaves. Our results show that mycorrhization increased the plant dry biomass by about 57%. The rate of mycorrhizal colonization ranged from 25% to 30%. Peroxidase activity in roots colonized by T. harzianum alone was 1.6 times higher than in control plants. Peroxidase activity in roots colonized by G. mosseae and T. harzianum was about 2 times higher than in control plants. Peroxidase activity in leaves increased by + 419% when plants were inoculated by both fungi. The cytochemical results show an accumulation of structural substances in root cell walls after inoculation with T. harzianum. These structural substances may increase the mechanical strength of the host cell walls in order to inhibit pathogen invasion. Peroxidase activities were found in plant cell walls; the tonoplast and host plasmalemma in the chloroplast; mitochondrial membranes; and intercellular spaces of plants inoculated with G. mosseae and T. harzianum. SDS-PAGE analyses of leaf extracts gave a main band at 54 kDa for all the treatments. The stimulatory effect of Trichoderma on the peroxidase activity is a resistance mechanism of date plants to pathogens. The use of Trichoderma could thus be an alternative to chemicals in crop protection.

Fue en 1999 cuando Vicente Borrás de la Escuela de Capataces Agrícolas de Catarroja, Valencia, me presentó a Mario Honrubia. Yo deseaba incursionar en el campo de las micorrizas más seriamente y el Grupo de Investigación (GI) de Mario buscaba de nuevo un/a doctorando/a para uno de sus numerosos proyectos de investigación. Ya en esa primera conversación se mencionó el posible tema de investigación: “Micorrizas de palmeras”. De ahí siguió la solicitud de beca y a los pocos meses estaba en la Universidad de Murcia, formando parte de la “familia micológica-micorrizóloga”, desde 2000 a 2004 de forma presencial y a partir de 2004 como colaboradora en el extranjero. He tratado de hacer memoria sobre esas primeras impresiones hacia el nuevo GI y hacia el nuevo tema. Se resume en tres palabras “apertura internacional”, “exotismo” y “modernidad”.

La palabra micorriza signifi ca hongo-raíz y se usa para definir las asociaciones simbióticas formadas entre los hongos y las raíces de las plantas, en donde ambos simbiontes, tanto la planta como el hongo, obtienen benefi cios de vivir en una estrecha relación de mutua dependencia. Uno de los benefi cios más conocidos es el intercambio nutricional, en el que la planta le da al hongo carbohidratos y el hongo a la planta nutrientes minerales del suelo. Además de la mejora nutricional y el consecuente aumento del crecimiento, los hongos micorrícicos aportan muchos más benefi cios a las plantas, como se presenta más adelante.

Las enfermedades crónicas no transmisibles dentro de las cuales se encuentra la dislipidemia; constituyen un obstáculo considerable para el crecimiento económico y el desarrollo social de los países de la región de América Latina y del Caribe. Según estadísticas de la Organización Mundial de la Salud (OMS), el 61% de todas las muertes y el 49% de la carga mundial de morbilidad son atribuibles a enfermedades crónicas. Se estima que para el año 2030 la proporción del total mundial de defunciones debidas a estas enfermedades llegará al 70% y la carga mundial de morbilidad al 56%. En El Salvador, las estadísticas referentes a la dislipidemia la señalan como la tercera entre las enfermedades crónicas no transmisibles más prevalente. Actualmente el manejo médico de las dislipidemias se realiza mediante el uso de los medicamentos derivados de las estatinas. Sin embargo, varias investigaciones sugieren que muchos recursos naturales entre estas las plantas (hojas, tallo, corteza, semillas y flores) contienen múltiples componentes bioactivos que pueden influir de manera favorable en el control de dicha enfermedad. La familia de las Cucurbitáceas posee compuestos que pueden afectar el metabolismo de los lípidos tales como; saponinas, flavonoides y taninos. El objetivo de esta investigación es evaluar la toxicidad y la actividad hipolipemiante de la decocción de la flor de Cucurbita moschata "ayote" en ratones experimentales para comprobar su eficacia como tratamiento de la dislipidemia.