40 research outputs found
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 gâ1 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 estĂĄn 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 ĂĄrtica y antĂĄrtica. Sanionia uncinata Hedw. (Amblystegiaceae) es uno de los musgos mas importante del territorio AntĂĄrtico. Su contenido hĂdrico depende de la humedad ambiental, razon por la cual, debido a las condiciones ambientales en durante el verano antartico, estĂĄ constantemente sometido a desecaciĂłn. Muchas plantas al estar sometidas a desecaciĂłn acumulan osmĂłlitos compatibles, principalmente hidratos de carbonos y los aminoĂĄcidos. Estudios previos de nuestro grupo han determinado que esta especie acumula altos niveles de azĂșcares, en particular de rafinosa. Por estos antecedentes se evaluĂł la participaciĂłn de la acumulaciĂłn de azĂșcares en la tolerancia a la desecaciĂłn en el musgo antĂĄrtico S. uncinata, mediante cromatografĂa lĂquida de alta eficiencia con detector de Ăndice de refracciĂłn (HPLC-RIA). Los resultados obtenidos mostraron que el tipo de azĂșcar acumulado depende del nivel de perdida de agua. A niveles de pĂ©rdida menor o iguales al 65% se acumulĂł rafinosa y verbascosa, mientras que a niveles de pĂ©rdida de agua mayores al 65%, acumulĂł principalmente verbascosa. Estos hidratos de carbono actuarĂan como agentes antioxidantes, crioprotectores y agentes inhibidores de la fusiĂłn de membranas y destoxificantes de galactosa, permitiendo la recuperaciĂłn de S. uncinata. Finalmente, se concluye que el metabolismo de la rafinosa es un factor clave en la tolerancia a la desecaciĂłn de S. uncinata
DistribuciĂłn de garrapatas en 25 municipios del departamento de Antioquia.
Un estudio en 274 fincas ganaderas representativas de explotaciones de leche y carne, demostrĂł que la garrapata Boophilus microplus apareciĂł ampliamente distribuida en el ganado bovino en 25 municipios del departamento de Antioquia, localizados en climas cĂĄlidos, templados y frĂos con altitudes comprendidas entre 123 y 2562 m. AdemĂĄs se encontrĂł parasitando equinos y ovinos. La garrapata Anocentor nitens se hallĂł en equinos de todos los climas y tambiĂ©n en bovinos, mientras que la Rhipicephalus sanguineus fuĂ© recolectada en caninos de climas cĂĄlidos y templados. La Amblyomma cajennense y la Amblyomma ovale se encontraron en mĂnimas cantidades en climas cĂĄlidos en equinos y caninos respectivament
Genotyping of clinical isolates of Aspergillus flavus and its relationship with environmental isolates center
Antecedentes: Durante un perĂodo 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 oncohematolĂłgico de Buenos Aires, Argentina. Objetivos: Conocer la variabilidad y la relaciĂłn genĂ©tica entre los aislamientos clĂnicos y los ambientales obtenidos en el centro oncohematolĂłgico. MĂ©todos: Se utilizaron 2 tĂ©cnicas de genotipificaciĂłn con diferente poder discriminatorio (RAPD y AFLP). Una matriz de similitud genĂ©tica fue calculada usando el mĂ©todo de Jaccard y fue la base para la cons- trucciĂłn de un dendrograma por el mĂ©todo de UPGMA. Se estimĂł el nivel de variabilidad genĂ©tica por medio del porcentaje de loci polimĂłrficos, nĂșmero de alelos efectivos y heterocigosidad esperada, y el Ăndice de asociaciĂłn (I A ) . Resultados: El dendrograma mostrĂł que los aislamientos de A. flavus recuperados de los pacientes no se relacionaron genĂ©ticamente con los del ambiente nosocomial. Los valores mĂĄs altos de diversidad genĂ©- tica correspondieron a los aislamientos ambientales. El I A estimado para todos los aislamientos sugiere eventos de recombinaciĂłn. Conclusiones: Los pacientes 1 y 2 no fueron infectados con los aislamientos obtenidos del ambiente hospitalario. Los aislamientos clĂnicos y ambientales de A. flavus mostraron alta variabilidad genĂ©tica entre ellos
Effect of gramine in the resistance of barley seedlings to the aphid Rhopalosiphum padi
Gramine (N,NâDimethylâ3âaminomethylindole) 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 rĂ©sistance de plantules de seigle des puceron Rhopalosiphum padi La teneur de gramine (N,Nâdimethylâ3âaminoâmethylâindole) dans diffĂ©rentes cultures de seigle prĂ©sente des variations comprises entre 0 et 2,8 mmoles/Kg (poids frois). Les varietĂ©s dĂ©pourvues de gramine sont plus sensibles Ă 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 30â80 min and nonâphloem for 20â40 min, over a period of 3 h. In cultivar Datil âSâ, gramine was found only in the epidermis and parenchyma mesophyll cells. On this cultivar, the nonâphloem wave form of S. graminum was not observed. On F. Union, R. padi ingested nonâphloem with short periods of ingestion from phloem. On cv. Datil âSâ, this aphid did not show the nonâphloem 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 ÎČ-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-ÎČ-glucosidase was in the vacuole. This seems to be an efficient mechanism to prevent aglycone toxicity in vivo. © 1994