Sorbed Anthracene Degradation by Sophorolipid Producing Yeasts

The organic pollutan adsorption/desorption process by microbial degradation had been less studied than metal ones. The sorption assays alone did not predict desorption, due to hysteresis, irreversibility, fixed compounds in different sites, with diverse desorption rates. Most of the studies dealt with bacteria rather than filamentous fungi and yeasts. So, our aims were to isolate yeasts from polluted sediments, to quantify its potential to uptake anthracene (An) and to evaluate the bioavailability by a desorption model. Yeasts were isolated from hydrocarbon-polluted samples, 40-isolates grew in anthracene-plates. Molecular characterization was achieved by sequence analysis of the ITS1-5.8S rRNA-ITS4 and 26S rRNA regions; morphological and physiological determination were also done. Candida parasilopsis, Pichia anomala and Rhodothorula mucilaginosa were the prevalent yeasts. An-degradation was assessed in soil-systems with 0, 50, 100, 150, 200 and 250 µg An/l, 3 differentes sorbens types, organic carbon, organic nitrogen, PAHs, sand:silt:clay, pH and cation exchange capacity. Sophorolipids excretion were confirmed by HPLC, UV-detector with active fraction at 9.669 min (RT 9.646 min = sophorolipid-standard). A desorption model with equilibrium, nonequilibrium and nondesorption areas, was applied to explain the experimental data, An-transformation was greater in the organic liquid-phase than in the soil-sorbed ones; the desorption-coefficients and soil components were negatively correlated with the kinetic parameters. The An-release depended on the sophorolipid excretion, soil matrix and particles sizes. Desorption parameters significantly fitted the yeast uptake, with R2 = 0.97, R2 = 0.90 and R2 = 0.97 for C. parasilopsis, P. anomala and R. mucilaginosa, respectively

Anatomical Studies of Two Jatropha Species with Importance for Biodiesel Production

Jatropha curcas L. and Jatropha macrocarpa Griseb. (Euphorbiaceae) are perennial species adapted to marginal conditions not suitable for agriculture, and have been recently exploited for oil and biodiesel production. The anatomy of different organs in members of this family exhibits a wide range of variations. However, knowledge of anatomical features is still incomplete. The aim of the present work was to analyze the anatomical structure of stem, leaf and root of J. curcas and J. macrocarpa seedling cultivated in a greenhouse. Fixed samples were properly treated using triple stain hematoxylin, safranin and fast green. Primary roots were diarch and triarch in J. curcas, whereas in J. macrocarpa were diarch and the cortex showed parenchyma cells, larger in J. macrocarpa than J. curcas. Stem cortex was thicker in J. macrocarpa than in J. curcas. Both species had parenchyma cells with cystolith, chloroplasts, laticifers and starch granules, these being more abundant in J. macrocarpa. Leaves were characterized by dorsoventral anatomy, with the epiderm showing amphistomatic condition with high stomata density at the lower surface. Both Jatropha species had paracytic stomata. Druses and non-articulated branched laticifers were recorded in the mesophyll. Some of the different anatomical features of J. curcas and J. macrocarpa could explain the different tolerance to abiotic stress

Micosis asociadas a pacientes VIH + / SIDA

Diferentes factores asociados al desarrollo y al progreso, han logrado que la prevalencia de las micosis se haya incrementado dramáticamente en los últimos años, hecho relacionado con el deterioro de los mecanismos defensivos que le permiten al individuo normal contrarrestar estas enfermedades. Indudablemente los avances de la medicina han producido como contrapartida un aumento de las infecciones oportunistas, donde se encuentran mohos y levaduras ambientales y propias del hombre como patógenos potenciales, aunque ninguno de los factores citados han influido tanto en el aumento de la incidencia de las micosis, como la pandemia del SIDA a partir del año 1980, donde la población susceptible a las micosis oportunistas se ha incrementado notablemente, aumentando también el número de especies fúngicas involucradas (emergentes), dando origen a manifestaciones clínicas diversas que van desde un cuadro febril mal definido a un estado septicémico fatal, así como nuevas nomenclaturas, clasificaciones y criterios taxonómicos.Mesa: Micosis HIV-SIDA.Facultad de Ciencias Veterinaria

Micosis asociadas a pacientes VIH + / SIDA

Diferentes factores asociados al desarrollo y al progreso, han logrado que la prevalencia de las micosis se haya incrementado dramáticamente en los últimos años, hecho relacionado con el deterioro de los mecanismos defensivos que le permiten al individuo normal contrarrestar estas enfermedades. Indudablemente los avances de la medicina han producido como contrapartida un aumento de las infecciones oportunistas, donde se encuentran mohos y levaduras ambientales y propias del hombre como patógenos potenciales, aunque ninguno de los factores citados han influido tanto en el aumento de la incidencia de las micosis, como la pandemia del SIDA a partir del año 1980, donde la población susceptible a las micosis oportunistas se ha incrementado notablemente, aumentando también el número de especies fúngicas involucradas (emergentes), dando origen a manifestaciones clínicas diversas que van desde un cuadro febril mal definido a un estado septicémico fatal, así como nuevas nomenclaturas, clasificaciones y criterios taxonómicos.Mesa: Micosis HIV-SIDA.Facultad de Ciencias Veterinaria

Micosis asociadas a pacientes VIH + / SIDA

Diferentes factores asociados al desarrollo y al progreso, han logrado que la prevalencia de las micosis se haya incrementado dramáticamente en los últimos años, hecho relacionado con el deterioro de los mecanismos defensivos que le permiten al individuo normal contrarrestar estas enfermedades. Indudablemente los avances de la medicina han producido como contrapartida un aumento de las infecciones oportunistas, donde se encuentran mohos y levaduras ambientales y propias del hombre como patógenos potenciales, aunque ninguno de los factores citados han influido tanto en el aumento de la incidencia de las micosis, como la pandemia del SIDA a partir del año 1980, donde la población susceptible a las micosis oportunistas se ha incrementado notablemente, aumentando también el número de especies fúngicas involucradas (emergentes), dando origen a manifestaciones clínicas diversas que van desde un cuadro febril mal definido a un estado septicémico fatal, así como nuevas nomenclaturas, clasificaciones y criterios taxonómicos.Mesa: Micosis HIV-SIDA.Facultad de Ciencias Veterinaria

Effects of the sorption/desorption process on the fluoranthene degradation by wild strains of Hansenula angusta and Rhodotorula minuta

The fluoranthene degradation was predicted by the sorption/desorption process as its fungal transformation was in relationship with the bioavailabit. Toxicants availability is significant to assess as their bioremediation and persistence in the contaminated environment depended on the physical, chemical and textures of the polluted sediments that fixed the organic xenobiotics. In most of natural and man-made habitats, the aromatic hydrocarbons had been found sorbed to soil particles that inmobilized the compounds and diminished the microbial attack. Therefore, wild yeasts from hydrocarbon polluted areas were isolated, and their potential as fluoranthene degraders were evaluated in different texture soils and organic matter contents. Hansenula angusta and Rhodotorula minuta were isolated from industrial effluents and used in desorption experiments; the obtained Flu uptake parameters explained the efficiency of both yeasts to biotransform Flu sorbed to soil particles. H. angusta and R. minuta degraded Flu by bioemulsifiers production; evenmore, they were highly efficient to uptake fluoranthene in the biphasic cultures and were dominant in the sampled polluted sediments. The potential application of biosurfactants produce by indigenous yeasts in PAHs recovery from the polluted environments was demonstrated by the percentage of fluoranthene removal and by the stability of the surface tension.Fil: Romero, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología; ArgentinaFil: Urrutia, María Inés. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Reinoso, Enso H.. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología; ArgentinaFil: Moreno Kiernan, Alejandro Ricardo. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; Argentin

Low-temperature phase of hexaguanidinium hepta­molybdate monohydrate

The crystal structure of the title compound, [C(NH2)3]6[Mo7O24]·H2O, previously determined at room temperature in the monoclinic space group C2/c from Weissenberg techniques [Don & Weakley (1981 ▶). Acta Cryst. B37, 451–453], has been redetermined from low-temperature single-crystal data in the monoclinic space group P21/c. The asymmetric unit contains one hepta­molybdate anion, six guanidinium cations and one water mol­ecule of hydration. The anions and cations are linked by an extensive network of N—H⋯O hydrogen bonds

Photovoltaic generation model as a function of weather variables using artificial intelligence techniques

The optimisation of photovoltaic systems of electricity generation involve the necesity of real data of the different variables as well as determination of their relationships. In the field of photovoltaic solar energy there is interest to predict the energy generation in terms of solar radiation and climatic parameters. For this purpose, it is needed a good sensing and measurement of these parameters. In this paper, we propose a method based on artificial intelligence techniques for obtaining the generated energy under climatic conditions during a year. In addition, we propose a model that relates short-circuit current with radiation, considering the true nonlinear behavior of the relationship between variables. The results of the proposed method using real data show its validity and usefulness in predicting the generated energy by photovoltaic modules and the search for alternative methods of measuring global radiation at low cost and reasonable error.Fil: Sánchez Reinoso, Carlos Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Cutrera, M.. Universidad Nacional de Catamarca; ArgentinaFil: Battioni, M.. Universidad Nacional de Catamarca; ArgentinaFil: Milone, Diego Humberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Buitrago, R. H.. Universidad Nacional de Catamarca; Argentin

Atrazine degradation by wild filamentous fungi

Bioremediation is a promising technology for the treatment of polluted areas due to its minor cost;moreover, indigenous fungi had not been already applied to detoxify contaminated habitats. The kinetic of atrazine degradation by Gliocladium roseum, Mucor alternans and Pycnidiophora dispersa were assessed in soluble and soil sorbed herbicide with different organic matter content. Their half-saturation constants, Km, expressed the affinity for the substrate, being 12.5, 3.8 and 2.7 μg/ml for G. roseum, M. alternans and P. dispersa. Moreover, Vmax, uptake rate/ biomass, assumed by the asymptotes of each fungal curves were 43.5-41.0, 37.5-35.0 and 26.5-24.5 μg Atz/min-1. mg for G. roseum, M. alternans and P. dispersa, respectivelly. The 65-75% was in soluble phase, that was preferentially degraded by fungi. Our results showed that the atrazine transformation were consistent with those in pure cultures, suggesting that the parameters derived from in-vitro studies may be useful to predict the herbicide detoxification in polluted sediments. Fungal kinetic allowed us to predict the atrazine degradation in natural contaminated habitats and was in relation to the herbicide levels especially in soil solutions.Fil: Romero, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología; ArgentinaFil: Urrutia, María Inés. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Reinoso, Enso H.. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología; ArgentinaFil: Della Vedova, Romina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología; ArgentinaFil: Reynaldi, Francisco José. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología. Cátedra de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

Variability in concentrations of potentially toxic elements in urban parks from six European cities

Use of a harmonised sampling regime has allowed comparison of concentrations of copper, chromium, nickel, lead and zinc in six urban parks located in different European cities differing markedly in their climate and industrial history. Wide concentrations ranges were found for copper, lead and zinc at most sites, but for chromium and nickel a wide range was only seen in the Italian park, where levels were also considerably greater than in other soils. As might be expected, the soils from older cities with a legacy of heavy manufacturing industry (Glasgow, Torino) were richest in potentially toxic elements (PTEs); soils from Ljubljana, Sevilla and Uppsala had intermediate metal contents, and soils from the most recently established park, in the least industrialised city (Aveiro), displayed lowest concentrations. When principal component analysis was applied to the data, associations were revealed between pH and organic carbon content; and between all five PTEs. When pH and organic carbon content were excluded from the PCA, a distinction became clear between copper, lead and zinc (the "urban" metals) on the one hand, and chromium and nickel on the other. Similar results were obtained for the surface (0-10 cm depth) and sub-surface (10-20 cm depth) samples. Comparisons with target or limit concentrations were limited by the existence of different legislation in different countries and the fact that few guidelines deal specifically with public-access urban soils intended for recreational use