Soluble carbohydrate content variation in Sanionia uncinata and Polytrichastrum alpinum, two Antarctic mosses with contrasting desiccation capacities

Additional file 1: Table S1. Non structural carbohydrate content (mg g−1 DW) of two Antarctic moss species expossed to desiccation and rehydration treatment under controlled conditions

TOLERANCIA LA DESECACION EN BRIOFITAS . PARTICIPACION DE AZUCARES

Las plantas están constantemente expuestas a condiciones adversas que afectan su desarrollo. En muchas plantas, la falta de agua en el suelo, provoca daño singnificativo, que puede ocasionar su muerte. Solo una pocas especies presentan mecanismos, que les permiten tolerar periodos prolongados de falta de agua en el ambiente. Las briofitas o musgos colonizan biomas tales como bosques tropicales, desiertos, tundras ártica y antártica. Sanionia uncinata Hedw. (Amblystegiaceae) es uno de los musgos mas importante del territorio Antártico. Su contenido hídrico depende de la humedad ambiental, razon por la cual, debido a las condiciones ambientales en durante el verano antartico, está constantemente sometido a desecación. Muchas plantas al estar sometidas a desecación acumulan osmólitos compatibles, principalmente hidratos de carbonos y los aminoácidos. Estudios previos de nuestro grupo han determinado que esta especie acumula altos niveles de azúcares, en particular de rafinosa. Por estos antecedentes se evaluó la participación de la acumulación de azúcares en la tolerancia a la desecación en el musgo antártico S. uncinata, mediante cromatografía líquida de alta eficiencia con detector de índice de refracción (HPLC-RIA). Los resultados obtenidos mostraron que el tipo de azúcar acumulado depende del nivel de perdida de agua. A niveles de pérdida menor o iguales al 65% se acumuló rafinosa y verbascosa, mientras que a niveles de pérdida de agua mayores al 65%, acumuló principalmente verbascosa. Estos hidratos de carbono actuarían como agentes antioxidantes, crioprotectores y agentes inhibidores de la fusión de membranas y destoxificantes de galactosa, permitiendo la recuperación de S. uncinata. Finalmente, se concluye que el metabolismo de la rafinosa es un factor clave en la tolerancia a la desecación de S. uncinata

Distribución de garrapatas en 25 municipios del departamento de Antioquia.

Un estudio en 274 fincas ganaderas representativas de explotaciones de leche y carne, demostró que la garrapata Boophilus microplus apareció ampliamente distribuida en el ganado bovino en 25 municipios del departamento de Antioquia, localizados en climas cálidos, templados y fríos con altitudes comprendidas entre 123 y 2562 m. Además se encontró parasitando equinos y ovinos. La garrapata Anocentor nitens se halló en equinos de todos los climas y también en bovinos, mientras que la Rhipicephalus sanguineus fué recolectada en caninos de climas cálidos y templados. La Amblyomma cajennense y la Amblyomma ovale se encontraron en mínimas cantidades en climas cálidos en equinos y caninos respectivament

Genotyping of clinical isolates of Aspergillus flavus and its relationship with environmental isolates center

Antecedentes: Durante un período de 4 meses, y mientras se llevaba a cabo un muestreo ambiental de aire, se diagnosticaron 2 casos de aspergilosis por Aspergillus flavus en un centro oncohematológico de Buenos Aires, Argentina. Objetivos: Conocer la variabilidad y la relación genética entre los aislamientos clínicos y los ambientales obtenidos en el centro oncohematológico. Métodos: Se utilizaron 2 técnicas de genotipificación con diferente poder discriminatorio (RAPD y AFLP). Una matriz de similitud genética fue calculada usando el método de Jaccard y fue la base para la cons- trucción de un dendrograma por el método de UPGMA. Se estimó el nivel de variabilidad genética por medio del porcentaje de loci polimórficos, número de alelos efectivos y heterocigosidad esperada, y el índice de asociación (I A ) . Resultados: El dendrograma mostró que los aislamientos de A. flavus recuperados de los pacientes no se relacionaron genéticamente con los del ambiente nosocomial. Los valores más altos de diversidad gené- tica correspondieron a los aislamientos ambientales. El I A estimado para todos los aislamientos sugiere eventos de recombinación. Conclusiones: Los pacientes 1 y 2 no fueron infectados con los aislamientos obtenidos del ambiente hospitalario. Los aislamientos clínicos y ambientales de A. flavus mostraron alta variabilidad genética entre ellos

Effect of gramine in the resistance of barley seedlings to the aphid Rhopalosiphum padi

Gramine (N,N‐Dimethyl‐3‐aminomethylindole) content in various barley cultivars varied from 0 to 2.6 mmoles/kg fresh weight. Those cultivars which were lacking gramine were the most susceptible to the aphid Rhopalosiphum padi (L.). The population growth rate of R. padi negatively correlated with gramine content in leaves of barley seedlings. In addition, gramine incorporated in artificial diets decreased survival, amount of diet ingested and reproduction of aphids at concentrations similar to those found in plant leaves. Thus, it is suggested that gramine may be one of the factors responsible for the resistance of barley seedlings to R. padi. Effet de la gramine sur la résistance de plantules de seigle des puceron Rhopalosiphum padi La teneur de gramine (N,N‐dimethyl‐3‐amino‐methyl‐indole) dans différentes cultures de seigle présente des variations comprises entre 0 et 2,8 mmoles/Kg (poids frois). Les varietés dépourvues de gramine sont plus sensibles à l'attaque des pucerons. Le taux

Soluble carbohydrate content variation in Sanionia uncinata and Polytrichastrum alpinum, two Antarctic mosses with contrasting desiccation capacities

BACKGROUND: Cryptogamic vegetation dominates the ice-free areas along the Antarctic Peninsula. The two mosses Sanionia uncinata and Polytrichastrum alpinum inhabit soils with contrasting water availability. Sanionia uncinata grows in soil with continuous water supply, while P. alpinum grows in sandy, non-flooded soils. Desiccation and rehydration experiments were carried out to test for differences in the rate of water loss and uptake, with non-structural carbohydrates analysed to test their role in these processes. RESULTS: Individual plants of S. uncinata lost water 60 % faster than P. alpinum; however, clumps of S. uncinata took longer to dry than those of P. alpinum (11 vs. 5 h, respectively). In contrast, rehydration took less than 10 min for both mosses. Total non-structural carbohydrate content was higher in P. alpinum than in S. uncinata, but sugar levels changed more in P. alpinum during desiccation and rehydration (60-50 %) when compared to S. uncinata. We report the presence of galactinol (a precursor of the raffinose family) for the first time in P. alpinum. Galactinol was present at higher amounts than all other non-structural sugars. CONCLUSIONS: Individual plants of S. uncinata were not able to retain water for long periods but by growing and forming carpets, this species can retain water the longest. In contrast individual P. alpinum plants required more time to lose water than S. uncinata, but as moss cushions they suffered desiccation faster than the later. On the other hand, both species rehydrated very quickly. We found that when both mosses lost 50 % of their water, carbohydrates content remained stable and the plants did not accumulate non-structural carbohydrates during the desiccation prosses as usually occurs in vascular plants. The raffinose family oligosaccarides decreased during desiccation, and increased during rehydration, suggesting they function as osmoprotectors

Instalaciones frigorificas para camaras de maracuya

PRESENTA UN ESTUDIO DE FACTIBILIDAD DE LAS EXPORTACIONES DEL MARACUYA CON RESPECTO AL DESARROLLO DE LAS INDUSTRIAS PROCESADORAS DE MARACUYA EN EL ECUADOR. SE EXPONEN CARACTERISTICAS DEL MARACUYA COMO MATERIA PRIMA. SE ENFOCA EL PROCESAMIENTO PARA OBTENER LOS PRODUCTOS DERIVADOS, Y LOS EQUIPOS PARA EL PROCESAMIENTO A ESCALA INDUSTRIAL. DESCRIBE EL CALCULO DE LAS DIMENSIONES DE LOS LOCALES FRIGORIFICOS USANDO TAMBORES DE ACEROS A 55 GALONES REALIZANDO SU MANIPULEO CON MONTACARGAS. TRATA ADEMAS SOBRE LA TERMODINAMICA DEL CICLO DE REFRIGERACION DEL REFRIGERANTE ESCOGIDO. SE CONCLUYE CON LA SELECCION DE LOS DISPOSITIVOS DE CONTROL Y EQUIPOS ANEXOS DE LOS LOCALES PARA UN BUEN FUNCIONAMIENTO Y SERVICIO DE LOS MISMOS. MH/CIBGZ-FIMCP 21.04.0

Extracts of Fruits and Plants Cultivated In Vitro of <i>Aristotelia chilensis (Mol.) Stuntz</i> Show Inhibitory Activity of Aldose Reductase and Pancreatic Alpha-Amylase Enzymes

Aristotelia chilensis is a plant whose fruit is considered a powerful natural antioxidant. During the last years, some investigations of the fruit have been carried out, finding antioxidant properties in the juice or the phenolic fraction. The antioxidant properties of the plant are useful in the inhibition of enzymes related to diabetes such as pancreatic aldose reductase and alpha-amylase. Because many synthetic drugs used today have limitations and potentially harmful side effects, the use of naturally occurring compounds, such as flavonoids, is clinically attractive. In this study, the characterization of aqueous extracts of fruits and in vitro plants of A. chilensis was carried out based on their content of anthocyanins and total phenols, the antioxidant capacity by the antiradical activity 2,2-diphenyl-1-picrilhydrazil (DPPH), and the profile of anthocyanins and other phenolic compounds by liquid chromatography coupled to mass spectrometry (LC-MS/MS). Subsequently, the effect of these extracts on the inhibition of bovine aldose reductase and pancreatic alpha-amylase enzymes was determined. According to our results, extracts of fruits and in vitro plants of A. chilensis achieved inhibition of the bovine aldose reductase enzyme of 85.54 ± 1.86% and 75.67 ± 1.21%, respectively. Likewise, the percentage of inhibition of the pancreatic alpha-amylase enzyme for fruit extracts was 29.64 ± 0.63%, while for in vitro plant extracts it was 47.66 ± 0.66%. The antioxidant and enzymatic inhibition activity of the extracts were related to the content of anthocyanins, such as delphinidin and cyanidin glycosides as well as the phenols derived from quercetin, myricetin, and kaempferol. The results obtained allow us to suggest that the in vitro culture of plants of A. chilensis represents a viable biotechnological alternative to obtain phenolic compounds for the inhibition of aldose reductase and pancreatic alpha-amylase enzymes

Effect of gramine on the feeding behavior of the aphids Schizaphis graminum and Rhopalosiphum padi

The effects of the indole alkaloid gramine on the behavior of the aphids Schizaphis graminum and Rhopalosiphum padi feeding on barley seedlings and on artificial diets were studied. On barley cv. F. Union, which lacks gramine, S. graminum ingested from phloem tissue for 30–80 min and non‐phloem for 20–40 min, over a period of 3 h. In cultivar Datil ‘S’, gramine was found only in the epidermis and parenchyma mesophyll cells. On this cultivar, the non‐phloem wave form of S. graminum was not observed. On F. Union, R. padi ingested non‐phloem with short periods of ingestion from phloem. On cv. Datil ‘S’, this aphid did not show the non‐phloem wave form. In experiments performed with cv. F. Union seedlings that contained exogenous gramine S. graminum did not ingest from phloem. Exogenous gramine was found only in the vascular bundles. It is suggested that gramine content and location may affect the feeding behavior of aphids in barley. Effects de la gramine sur le comportement alimentaire

Effects of hydroxamic acids on electron transport and their cellular location in corn

DIMBOA, the main hydroxamic acid in maize and wheat, is found mainly as a glucoside in intact maize plants; when the tissue is damaged a β-glucosidase releases DIMBOA from DIMBOA-glucoside. The effects of DIMBOA and its glucoside were studied in maize mitochondria and chloroplasts. DIMBOA reduced electron transport in both mitochondria and chloroplasts with an ID50 of 1.8 and 1.2 mM, respectively. DIMBOA-glucoside had no inhibitory effect. The glucoside and the enzyme were both present in mesophyll parenchyma protoplasts. When these protoplasts were fractionated, DIMBOA-glucoside was found in the extravacuolar fraction, while the DIMBOA-β-glucosidase was in the vacuole. This seems to be an efficient mechanism to prevent aglycone toxicity in vivo. © 1994