Estudio morfológico comparativo de algunos clones del género Uronema en condiciones de cultivo

El estudio del género uronema llevado a cabo por medio de los métodos de impregnación utilizados en taxonomia clásica, se ha abordado sobre varios clones aislados de diferentes procedencias geográficas y desde otros puntos de vista. Los métodos clásicos se han aplicado, en primer lugar, por medio de la utilización y comparación de las tres impregnaciones argenticas mayormente utilizadas. Esta parte permitio la identificación de cinco morompos entre los clones aislados, que han sido comparados con las descripciones bibliográficas en la asignación de especies. El estudio trofodinámico se ha llevado a cabo en segundo lugar como medio de comparación entre los distintos clones aislados o entre morfotipos aislados e identificados en la fase anterior. El estudio morfométrico de todos los clones sobre las dos fases de crecimiento en cultivo, se ha llevado a ..

Ciliate contributions to bioaggregation: laboratory assays with axenic cultures of Tetrahymena thermophila

Protists, mainly ciliates, play several essential roles in biological wastewater treatment, such as the transfer of matter and energy, bacterial predation, and the removal of organic material. Moreover, during the treatment process, the formation of bioaggregates—flocs and biofilms—is essential to obtaining high-quality effluents. In the present study, Tetrahymena thermophila was used as a model organism to demonstrate the contribution of ciliates to bioflocculation. Axenic cultures of this species were exposed to chemical and mechanical stimuli that promote bioaggregation. In either case, the secretion of a capsulate mucous material by the ciliates or by particle aggregation was detected. Numerous, small, loosely compacted flocs were observed under shaking conditions and in the presence of latex beads. The composition of the exopolymeric material secreted by ciliates was analyzed by a series of fluorochromes and colorimetric methods, which showed that carbohydrates and nucleic acids were the main components involved in matrix formation and particle adhesion. [Int Microbiol 2007; 10(2):91-96

Influencia de la temperatura sobre la asimetría de pilancones en ambiente granítico. Aplicación de un modelo de regresión lineal

Las pilas representan un tipo de forma presente en casi todos los ambientes climáticos. El trabajo estudia el papel de los ciclos térmicos como un agente importante del modelado y asimetría que presentan las paredes de las pilas en un clima Mediterrá- neo templado - frío. El estudio se ha realizado en el macizo granítico de la Pedriza de Manzanares, zona protegida de gran valor ambiental, incluida en el Parque Nacional de la Sierra de Guadarrama (Madrid, España). El análisis de la variabilidad térmica mediante modelos de regresión perió- dica múltiple, pone de manifiesto la influencia de los ciclos diario y anual en función de las orientaciones norte y sur de las paredes de las pilas. Un modelo matemático de regresión lineal muestra cómo la variabilidad térmica diaria influye en la alteración de las paredes de las pilas, generando superficies planas o de concavidad más o menos pronunciada. El trabajo también establece relaciones entre el grado de alteración de las diferentes partes de las pilas, con la presencia de líquenes y dureza relativa de la roca. Los resultados avalan la hipótesis de relación causal entre la variabilidad térmica y alteración de las paredes de las pilas según su orientación norte o sur

Diseño y utilización de unas prácticas de Regulación del Metabolismo como herramienta integradora de conocimientos multidisciplinares en el Grado en Biología (II)

Se pretende la creación de espacios multidisdiplinares en el Grado en Biología,con prácticas integradas de asignaturas que se cursan simultáneamente, que pudieran servir de base a propuestas de Trabajos de Fin de Grado

La curación de contenidos científicos como estrategia didáctica y divulgativa en Microbiología y otras áreas afines

Fac. de Ciencias BiológicasFALSEsubmitte

Involvement of Crawling and Attached Ciliates in the Aggregation of Particles in Wastewater Treatment Plants

The biological community in activated sludge wastewater plants is organized within this ecosystem as bioaggregates or flocs, in which the biotic component is embedded in a complex matrix comprised of extracellular polymeric substances mainly of microbial origin. The aim of this work is to study the role of different floc-associated ciliates commonly reported in wastewater treatment plants-crawling Euplotes and sessile Vorticella- in the formation of aggregates. Flocs, in experiments with ciliates and latex beads, showed more compactation and cohesion among particles than those in the absence of ciliates. Ciliates have been shown to contribute to floc formation through different mechanisms such as the active secretion of polymeric substances (extrusomes), their biological activities (movement and feeding strategies), or the cysts formation capacity of some species. Staining with lectins coupled to fluorescein showed that carbohydrate of the matrix contained glucose, manose, N-acetyl-glucosamine and galactose. Protein fraction revealed over the latex beads surfaces could probably be of bacterial origin, but nucleic acids represented an important fraction of the extracellular polymeric substances of ciliate origin

Involvement of Crawling and Attached Ciliates in the Aggregation of Particles in Wastewater Treatment Plants

The biological community in activated sludge wastewater plants is organized within this ecosystem as bioaggregates or flocs, in which the biotic component is embedded in a complex matrix comprised of extracellular polymeric substances mainly of microbial origin. The aim of this work is to study the role of different floc-associated ciliates commonly reported in wastewater treatment plants-crawling Euplotes and sessile Vorticella- in the formation of aggregates. Flocs, in experiments with ciliates and latex beads, showed more compactation and cohesion among particles than those in the absence of ciliates. Ciliates have been shown to contribute to floc formation through different mechanisms such as the active secretion of polymeric substances (extrusomes), their biological activities (movement and feeding strategies), or the cysts formation capacity of some species. Staining with lectins coupled to fluorescein showed that carbohydrate of the matrix contained glucose, manose, N-acetyl-glucosamine and galactose. Protein fraction revealed over the latex beads surfaces could probably be of bacterial origin, but nucleic acids represented an important fraction of the extracellular polymeric substances of ciliate origin.Ministerio de Ciencia y Tecnología (España)Universidad Complutense de MadridDepto. de Bioquímica y Biología MolecularFac. de FarmaciaFALSEpu

Ciliate contributions to bioaggregation: laboratory assays with axenic cultures of Tetrahymena thermophila

This work was supported by grant BOS2002-01042 from the Ministerio de Ciencia y Tecnología, SpainProtists, mainly ciliates, play several essential roles in biological wastewater treatment, such as the transfer of matter and energy, bacterial predation, and the removal of organic material. Moreover, during the treatment process, the formation of bioaggregates—flocs and biofilms—is essential to obtaining high-quality effluents. In the present study, Tetrahymena thermophila was used as a model organism to demonstrate the contribution of ciliates to bioflocculation. Axenic cultures of this species were exposed to chemical and mechanical stimuli that promote bioaggregation. In either case, the secretion of a capsulate mucous material by the ciliates or by particle aggregation was detected. Numerous, small, loosely compacted flocs were observed under shaking conditions and in the presence of latex beads. The composition of the exopolymeric material secreted by ciliates was analyzed by a series of fluorochromes and colorimetric methods, which showed that carbohydrates and nucleic acids were the main components involved in matrix formation and particle adhesion.Depto. de Microbiología y ParasitologíaFac. de Ciencias BiológicasTRUEpu

Anti-melanogenic and Anti-inflammatory Activities of Hibiscus sabdariffa

Hibiscus sabdariffa L., Malvaceae, is traditionally cultivated for its stem, leaves, calyces, and seeds as all parts have industrial, medicinal, and cosmetic applications. Likewise, there are many works on the biological properties of the aqueous extract of H. sabdariffa due to its high content of polyphenolic compounds. Using the Folin-Ciocalteu method, the total polyphenol content of an aqueous extract of a sample from Guatemala was found to be 15.97 ± 0.49 mg GAE/g. The presence of ten phenolic acids, ten flavonoids, and two anthocyanins was determined by 1 H NMR analysis. The anti-melanogenic activity assay of the aqueous extract showed inhibition of the tyrosinase activity (IC50 3.53 ± 0.16 μg/ml) and inhibition of the melanin production (IC50 3.90 ± 0.17 μg/ml) in the B16F10 cell line. Finally, the aqueous extract showed an inhibition of NO production with an IC50 of 4.72 ± 0.34 μg/ml and 3.62 ± 0.36 μg/ml in the RAW 264.7 and B16F10 cell lines, respectively. Our results allowed us to identify those polyphenolic compounds present in the aqueous extract of H. sabdariffa whose synergic effect increases the anti-melanogenic and anti-inflammatory properties of the aqueous extract