961 resultados para Uranium mill tailings


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Synthetic additives used in a wide variety of food products have been associated to some toxic effects. This conducted to an increasing interest of consumers for natural additives, including food preservers [1]. Many aromatic herbs have been used to prepare bioactive extracts with benefits to the consumer's health. Foeniculum vulgare Mill. (fennel) and Matricaria recutita L. (chamomile) are examples of popular herbs rich in phenolic compounds with documented antioxidant and antimicrobial properties [2,3]. The present work confirms the antioxidant (DPPH scavenging activity, reducing power and lipid peroxidation inhibition) and antimicrobial (against bacteria such as Bacillus cereus and Salmonella Typhimurium and fungi such as Aspergillus niger, A. versicolor and PenicilliumfimicuJosum) activities of fennel and chamomile extracts, obtained by decoction. The chemical characterization of the extracts, performed by HPLC-DAD-ESIIMS, revealed the presence of five flavonoids (mainly qercetin-3-0- glucoside) and twelve phenolic acids (mainly 5-0-caffeolyquinic acid) for fennel extract and the presence of nine flavonoids (mainly luteolin-0-glucuronide) and ten phenolic acids (mainly di-caffeoyl-2,7- anhydro-3-deoxy-2-octulopyranosonic acid) for chamomile extract. Due to their high antioxidant and antimicrobial activities, both extracts were then incorporated (at DPPH scavenging activity EC25 value: 0.35 mg/mL and 0.165 mg/mL for fennel and chamomile, respectively) in cottage cheeses (prepared by Queijos Casa Matias Lda) as natural additives with two objectives: to increase the shelf-life of the cottage cheeses and to provide bioactive properties to the final products. The results showed that the use of these natural extracts did not alter significantly the nutritional characteristics of the cottage cheese in comparison with control samples (cottage cheese without extracts), but improved its antioxidant potential (more evident in the samples with chamomile extract). After 14 days of storage, only the control samples showed signs of degradation. Overall, the present study highlights the preservation potential of fennel and chamomile extracts in cottage cheeses, improving also their bioactivity.

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Food industry is focused on the development of novel functional foods containing health promoting natural ingredients. Natural antioxidants present important health benefits like the prevention of several diseases related to oxidative stress [1,2]. Foeniculum vulgare Mill. (fennel) is a source of those compounds with proved antioxidant potential [3]. Herein, after evaluation of 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and reducing power of fennel (provided by Américo Duarte Paixão Lda.) decoction, we propose its incorporation into cottage cheese (produced by Queijos Casa Matias Lda.). Three groups of cottage cheese samples were prepared: control; samples with fennel decoction (incorporated at EC25 value=0.35 mg/mL, previously determined by DPPH assay); and samples with fennel powder (incorporated at 1.75 mg/mL, considering the decoction yield=20%). The samples were submitted to an evaluation of DPPH scavenging activity and reducing power immediately after the incorporations, and after 7 and 14 days of storage, at 4 ºC. The incorporation of fennel improved the antioxidant activity of cottage cheese. Samples incorporated with plant powder revealed higher antioxidant properties than samples incorporated with decoction, either in 0 or 7 days of storage. After 14 days, cottage cheese incorporated with fennel decoction gave the highest DPPH scavenging activity (46.72±0.09 mg/mL). A decrease in the antioxidant potential of the cottage cheese with fennel was observed along the shelf life. Nevertheless, it is important to highlight that the samples still display antioxidant properties. Studies regarding the effects of the incorporation of these natural ingredients on nutritional and chemical composition of cottage cheese are in course

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In this study, 123 almond (Prunus dulcis (Mill.) D. A. Webb) trees identified among traditional orchards in the Algarve region and 53 trees of the local field collection managed by the regional office of the Portuguese Ministry of Agriculture (DRAALG) were assessed using isozyme, inter- single sequence repeat and simple sequence repeat or microsatellite techniques for the evaluation of genetic diversity and genetic relatedness and identification of new accessions for the field collection. The isozyme analysis allowed the distribution of the 176 plants into 13 different classes of enzyme similarity, while the use of DNA markers increased the distribution of the analysed trees among 140 discriminating DNA patterns. Multiple cases of homonymy and synonymy were identified in the local germplasm. Some traditional varieties, such as Lourencinha, appeared to be relatively homogeneous, while other local denominations, e.g. Galamba, included diverse genotypes. Of the 13 commercial varieties analysed in this study, 11 assembled in one major cluster clearly differentiated from the majority of the local genotypes. These results reinforced the perception that the Algarve traditional germplasm constitutes an important repository of genetic diversity, eventually carrying alleles of high agricultural interest such as the recently identified Phomopsis resistance in the traditional variety Barrinho Grado.

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La biofortificación tiene como finalidad incrementar la concentración de elementos biodisponibles en las plantas de cultivo para elevar la calidad nutricional. El selenio es un elemento traza de gran impacto para el metabolismo antioxidante de las plantas y su acumulación es pobre en especies como el tomate, de igual manera este elemento es esencial para los humanos, por lo que adicionarlo en las plantas forma parte de los programas de biofortificación. El propósito de este trabajo fue analizar experimentalmente la capacidad del selenito de sodio para incrementar la concentración de Se y modificar la actividad antioxidante en plantas de tomate. Para ello se usaron plantas de la variedad híbrido Toro y se aplicaron tres tratamientos 0, 2 y 5 mg L-1 de selenito de sodio (Na2SeO3) utilizando como vehículo el agua de riego, los tratamientos fueron aplicados bajo un diseño experimental completamente al azar. Se llevaron a cabo tres muestreos 40, 80 y 120 días después del trasplante y la subsecuente cuantificación de la acumulación de selenio y macronutrientes en hojas, tallos y frutos así como su impacto en la producción de frutos bajo un diseño experimental completamente al azar. Se determinó la altura de la planta, los diámetros de tallos, firmeza, sólidos solubles de frutos y la materia seca total de los diferentes tejidos. Se obtuvo una cuantificación del potencial oxido reducción y de la actividad de antioxidante específicos como la catalasa, glutatión peroxidasa, superóxido dismutasa, el ácido ascórbico y licopeno, para cada variable se llevó a cabo un análisis de varianza y posteriormente una prueba de comparación de medias de Tukey. La expresión de los genes cat, gpx, sod, apx y lic en los frutos fue también analizada y en este caso se aplicó un análisis de varianza no paramétrico de Fisher, para encontrar las diferencias entre tratamientos. Los resultados mostraron un incremento en la acumulación de Se, encontrándose hasta un 53.1% de aumento en la concentración en los frutos bajo el tratamiento 5 mg L-1 en comparación con el testigo, sin embargo, este incremento no tuvo un impacto notorio en la producción y el rendimiento del tomate, a pesar de la existencia de una correlación de Spearman positiva (r =0.9637) entre la producción de fruto y la concentración de Se. Los valores del potencial oxido-reducción se redujeron en promedio desde -41.4 mV para el tratamiento testigo y hasta -68.0 mV con el mayor tratamiento. Mientras tanto, la concentración de Se si influyó positivamente en los parámetros de calidad incluyendo el ácido ascórbico (hasta un 50 % de aumento con el tratamiento 5 mgL-1 ) y el licopeno (hasta un 66.9% de aumento con el mayor tratamiento). La actividad de las enzimas antioxidantes aumentó notablemente en el fruto con el tratamiento 5 mg L-1 de selenito encontrándose 60.9% de aumento para CAT, 33.4% para GPX y 26.0% para SOD. En cuanto la expresión génica hubo mayor nivel de transcriptos de los genes gpx, sod y apx bajo el tratamiento 2 mg L-1

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La presente investigación se planteó reemplazar el uso de insecticidas sintéticos, formulando un champú bioinsecticida de aplicación canina mediante la acción biocida del aceite esencial deAmbrosia arborescens Mill (Altamisa). La planta se recolectó en las laderas del rio Tomebamba, cercanas al Campus Balzay de la Universidad de Cuenca Parroquia San Joaquín. La recolección se realizó durante los meses de Enero a Marzo del 2016. El desarrollo y formulación del producto se realizó en el Laboratorio de Biotecnología, Facultad de Ciencias Químicas de la Universidad de Cuenca. La obtención del aceite esencial de A. arborescens se realizó mediante hidrodestilación por el método Clevenger, con un rendimiento del 0,14%. La actividad biocida se estableció en un ensayo “in vitro” ante el nematodo Panagrellus redivirus, determinándose la dosis letal (DL50) de 250 uL/mL. Debido a la moderada DL50y bajo rendimiento, se planteó como estrategia, determinar el DL50 del extracto orgánico de A. arborescens, el cual se obtuvo mediante una extracción con metanol, consiguiendo un rendimiento del 2 % y DL50de 31,25 uL/mL. De acuerdo estos resultados se procedió a realizar pruebas en pulgas de perros(Ctenocephalides canis) con el extracto de A. arborescens, estableciendo una efectividad del 100 % a la concentración de 46,875 mg/mL en el periodo de tiempo más corto, siendo esta la dosis aplicada para la formulación del champú. El extracto metanólico de A. arborescens presentó elevada actividad biocida, comparado con el aceite esencial. Esta sustancia activa es promisoria en la formulación de bioinsecticidas para mascotas.

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Resumo: Diversos surtos de Salmonella ocasionados pelo consumo de tomate contaminados com este micro-organismo têm sido relatados ultimamente, o que torna primordial a investigação sobre a presença desse patógeno nesse alimento. Métodos que permitam a avaliação rápida da presença de Salmonella em alimentos são de suma importância. O objetivo desse estudo foi comparar o método tradicional da Food and Drug Administration - Bacteriologycal Analytical Manual (FDA-BAM) com um método rápido da mini Vitek Immuno Diagnostic System Assay (Mini?Vidas-SLM)-bioMérieux, para detecção de Salmonella Brazil inoculada artificialmente na superfície de tomates. Foram analisadas 215 amostras de tomates inoculadas artificialmente com Salmonella Brazil com níveis de inóculos variando de 0,4 a 940 UFC/tomate. Os resultados obtidos mostraram que os métodos estudados apresentaram uma ótima concordância entre si, para todas as faixas de inóculo analisadas.

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In this study, 123 almond (Prunus dulcis (Mill.) D. A. Webb) trees identified among traditional orchards in the Algarve region and 53 trees of the local field collection managed by the regional office of the Portuguese Ministry of Agriculture (DRAALG) were assessed using isozyme, inter- single sequence repeat and simple sequence repeat or microsatellite techniques for the evaluation of genetic diversity and genetic relatedness and identification of new accessions for the field collection. The isozyme analysis allowed the distribution of the 176 plants into 13 different classes of enzyme similarity, while the use of DNA markers increased the distribution of the analysed trees among 140 discriminating DNA patterns. Multiple cases of homonymy and synonymy were identified in the local germplasm. Some traditional varieties, such as Lourencinha, appeared to be relatively homogeneous, while other local denominations, e.g. Galamba, included diverse genotypes. Of the 13 commercial varieties analysed in this study, 11 assembled in one major cluster clearly differentiated from the majority of the local genotypes. These results reinforced the perception that the Algarve traditional germplasm constitutes an important repository of genetic diversity, eventually carrying alleles of high agricultural interest such as the recently identified Phomopsis resistance in the traditional variety Barrinho Grado.

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Gary, Indiana is a city with indelible ties to industrial paternalism. Founded in 1906 by United States Steel Corporation to house workers of the trust’s showpiece mill, the emergence of this model company town was both the culmination of lessons learned from its predecessors’ mistakes and innovative corporate planning. U.S. Steel’s Progressive Era adaptation of welfare capitalism characterized the young city through a combination of direct community involvement and laissez-faire social control. This thesis examines the reactionary implementation of paternalist policies in Gary between 1906 and 1930 through the purviews of three elements under corporate influence: housing, education, and social welfare. Each category demonstrates how both the corporation and citizenry affected and adapted Gary’s physical and cultural landscape, public perceptions, and community identity. Parallel to the popular narrative throughout is that of Gary’s African-American community, and the controversial circumstances of this population’s segregated development.

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The production of olive oil generates several by-products that can be seen as an additional business opportunity. Among them are the olive pits, already used for heat and/or electricity generation in some mills. They contain compounds that are commercially very interesting and, if recovered, contribute to the sustainability of the olive mills. The work presented in this paper is a preliminary evaluation of the economic feasibility of implementing a system based on a batch prototype with 1 m3 for the extraction of high value-added bioactive molecules from olive pits that are separated during the production of virgin olive oil. For the analysis, a small representative olive mill in Portugal was considered and the traditional Discounted Cash Flow Method was applied. Based on the assumptions made, the simple payback for implementation a system for the extraction of value-added molecules from the olive pits is around 7 years.

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In marginal lands Opuntia ficus-indica (OFI) could be used as an alternative fruit and forage crop. The plant vigour and the biomass production were evaluated in Portuguese germplasm (15 individuals from 16 ecotypes) by non-destructive methods, 2 years following planting in a marginal soil and dryland conditions. Two Italian cultivars (Gialla and Bianca) were included in the study for comparison purposes. The biomass production and the plant vigour were estimated by measuring the cladodes number and area, and the fresh (FW) and dry weight (DW) per plant. We selected linear models by using the biometric data from 60 cladodes to predict the cladode area, the FW and the DW per plant. Among ecotypes, significant differences were found in the studied biomass-related parameters and several homogeneous groups were established. Four Portuguese ecotypes had higher biomass production than the others, 3.20 Mg ha−1 on average, a value not significantly different to the improved ‘Gialla’ cultivar, which averaged 3.87 Mg ha−1. Those ecotypes could be used to start a breeding program and to deploy material for animal feeding and fruit production.

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A figueira-da-índia (Opuntia ficus-indica (L.) Mill.) é uma espécie com interesse para alimentação humana e animal, particularmente em áreas geográficas onde a disponibilidade de água é um fator limitante na atividade agrícola. Sendo considerada uma planta forrageira alternativa, pode produzir mais de 10 toneladas de matéria seca por hectare e, em condições limitantes de disponibilidade hídrica, supera as plantas C4 e C3 (Andrade-Montemayor et al., 2011). Acrescem ainda outras utilizações como sejam o controlo de erosão de solos, a constituição de barreiras anti-incêndio e a produção de biogás (Jigar et al., 2011, Sánchez et al., 2012). No contexto atual em que, por parte de alguns agricultores, renasceu o interesse por esta espécie, consideramos ser importante a caracterização e avaliação biométrica de populações portuguesas de O. ficus-indica e a sua comparação com variedades melhoradas, quer com o objetivo da produção de fruto para alimentação humana, quer como planta forrageira. Em maio de 2012 foram plantados, na Escola Superior Agrária de Castelo Branco (39º 49' 17.00''N; 7º 27' 41.00''W), num solo de baixa aptidão agrícola, cladódios de dezasseis populações portuguesas de O. ficus-indica, provenientes de diferentes locais e duas variedades italianas (Gialla e Bianca).