Estudios preliminares de los compuestos bioactivos y color de vinos rojos mexicanos de la región de Baja California

The total phenolic compounds, total anthocyanin content and antioxidant properties of ten commercially wines based on different grape cultivar from Baja California, Mexico were analyzed.  The results showed that the content of phenolic compounds of Vitis vinifera cv. Petit Verdot and  Petit Syrah  wines  had   the most highest values of  total phenolic content (1188.26   and 1148.13 mg GAE/L, respectively), with respect  the another  wines.  However, wines elaborated with three different cultivars (Cabernet Sauvignon/Petit Verdot/Merlot), and wine from cultivar Petit Verdot presented the highest total flavonoids content (161.06   mg QE/L and 182.64 mg QE/L, respectively) and total  anthocyanin content  (286.38 mg ME/L and 2548.56 mg ME/L, respectively). In contrast only wine from three grape cultivars (Cabernet Sauvignon/Petit Verdot/Merlot), and wine from cultivar Gamay, exhibits the highest antioxidant activity among tested wines. Finally, these results suggest that wine elaborated with different cultivars (Cabernet Sauvignon/Petit Verdot/Merlot), is more beneficial to health than others red wines in terms of its higher antioxidant activity, total anthocyanin content and total flavonoid contentSe analizaron los compuestos fenólicos totales, el contenido total de antocianinas y las propiedades antioxidantes de diez vinos comercialmente basados en diferentes cultivares de uva de Baja California, México. Los resultados mostraron que el contenido de compuestos fenólicos de Vitis vinifera cv., Petit Verdot y Petit Syrah presentaron los valores más altos de contenido fenólico total (1188,26 y 1148,13 mg GAE / L, respectivamente), con respecto a los otros vinos. Sin embargo, los vinos elaborados con tres cultivares diferentes (Cabernet Sauvignon / Petit Verdot / Merlot), y el vino del cultivar Petit Verdot presentaron el mayor contenido total de flavonoides (161.06 mg QE / L y 182.64 mg QE / L, respectivamente) y contenido total de antocianinas (286,38 mg ME / L y 2548,56 mg ME / L, respectivamente). En contraste, solo el vino de tres variedades de uva (Cabernet Sauvignon / Petit Verdot / Merlot) y el vino de la variedad Gamay exhiben la mayor actividad antioxidante entre los vinos probados. Finalmente, estos resultados sugieren que el vino elaborado con diferentes cultivares (Cabernet Sauvignon / Petit Verdot / Merlot), es más beneficioso para la salud que otros vinos tintos en cuanto a su mayor actividad antioxidante, contenido total de antocianinas y contenido total de flavonoide

Antifungal Effects of Silver Phytonanoparticles from Yucca shilerifera Against Strawberry Soil-Borne Pathogens: Fusarium solani and Macrophomina phaseolina

In the present study, the characterization and properties of silver nanoparticles from Yucca shilerifera leaf extract (AgNPs) were investigated using UV–visible spectroscopic techniques, zeta potential, and dynamic light scattering. The UV–visible spectroscopic analysis showed the absorbance peaked at 460 nm, which indicated the synthesis of silver nanoparticles. The experimental results showed silver nanoparticles had Z-average diameter of 729 nm with lower stability (195.1 mV). Additionally, our dates revealed that AgNPs showed broad spectrum antagonism (p ≤ .05) against Fusarium solani (83.05%) and Macrophomina phaseolina (67.05%) when compared to the control after nine days of incubation. Finally, AgNPs from leaf extracts of Y. shilerifera may be used as an agent of biocontrol of microorganism of importance. However, further studies will be needed to fully understand the agronanotechnological potentialities of AgNPs from Yucca schidigera

Evaluación de la presencia de hongos micorrízico arbusculares en un bosque de pino-encino en Chiapas, México

ABSTRACT Micorrizical fungi are an importan organisms in forest rhizospere. They are non timber forest products whose sustainable use must have an ecological basis. Pinarization effect and abundance of litter was determined on the percentage of mycorrhizal infection in roots in a pine-oak forest located in Ecatepec hill. The infection rates were 17.7% due to the work developed in a cool, dry season (February). The structures found in pine roots was as hyphae and vesicles. No effect of pinarización on the percentage of mycorrhizal infection was observed, however the depth of litter showed a statistically significant effect on the variable of infection, which may be due to the presence of litter benefits the soil microbial activity and also humidity and temperature of the litter layer favors the development of mycorrhizal fungi.RESUMEN Los hongos endomicorícicos son organismos importantes en la rizosfera del suelo. Constituyen productos no maderables cuyo uso sustentable deben tener una base ecológica. En este trabajo se evaluó el efecto que tiene la pinarización y la abundancia de hojarasca sobre el porcentaje de infección micorrízica en raíces de pino-encino ubicado en un bosque del cerro Ecatepec. Los porcentajes de infección fueron, en promedio, de 17.7% debido a que el trabajo se desarrolló en una temporada fresca y seca (febrero) encontrándose estructuras como hifas y vesículas. No se observó ningún efecto de la pinarización sobre el porcentaje de infección micorrízica, sin embargo la profundidad de hojarasca presentó un efecto estadísticamente significativo sobre la variable de infección, lo cual puede deberse a que la presencia de hojarasca beneficia la actividad microbiológica del suelo y además la humedad y temperatura de la capa de hojarasca favorece el desarrollo de hongos micorrízicos

Changes of photochemical efficiency and epidermal polyphenols content of Prosopis glandulosa and Prosopis juliflora leaves exposed to cadmium and copper

The effect of metals on the photosynthetic activities and epidermal polyphenol content of Prosopis glandulosa and Prosopis juliflora leaves was investigated by the tissue tolerance test. Foliar tissues of Prosopis glandulosa and Prosopis juliflora were incubated with Cd2+ (0.001 M) or Cu2+ (0.52 M) concentrations for 96 h. The results showed that significant reductions (p < 0.05) of photochemical efficiency in P. juliflora leaves were found after 96 h of exposure to 0.52 M Cu2+ compared with Cd-treatments and controls. In contrast, P. glandulosa leaves showed a progressive increase on photochemical efficiency at 72 h after Cu-treatment. The results also showed a significant decrease (p < 0.05) of epidermal polyphenols in P. juliflora leaves after 24 h of exposure to 0.52 M Cu2+ compared with Cd-treatments and control leaves. On the other hand, the values of leaf epidermal polyphenols observed in P. glandulosa exposed to copper and cadmium did not show any difference with respect to control. These findings are very important and suggest that these compounds could be considered as a protection mechanism of P. glandulosa when is treated with these heavy metals. Finally, the results of bioaccumulation showed that the copper concentration in P. glandulosa was higher than the values detected in P. juliflora Nevertheless, the cadmium concentration in foliar tissues of P. juliflora was significantly higher than P. glandulosa after 96 h of exposure to Cu2+ or Cd2+. Therefore, future studies are necessary to elucidate the effects of heavy metals on the biosynthesis of flavonoids and participation of these compounds in the reduction of metal toxicity in Prosopis species