Groundwater arsenic content in Raigón aquifer system (San José, Uruguay)

As a Medical Geology research issue, an environmental arsenic risk assessment study in the most important sedimentary aquifer in southern Uruguay is presented. The Raigón Aquifer System is the most exploited in Uruguay. It has a surface extent of about 1,800 square kilometres and 10,000 inhabitants in San Jose Department, where it was studied. Agriculture and cattle breeding are the main economic activities and this aquifer is the basic support. The groundwater sampling was done on 37 water samples of PRENADER (Natural Resources Management and Irrigation Development Program) wells. Outcropping sediments of Raigón Formation and the overlying Libertad Formation were also sampled in the Kiyú region. The analyses were performed by inductively coupled plasma-optical emission spectrometry (ICP-OES) and inductively coupled plasma-mass spectrometry (ICP-MS). The results showed 80% samples with arsenic levels exceeding the 10 μg/l of WHO as limit for waters, and 11% exceeds the 20 μg/l limit of uruguayan regulation. The median, maximum and minimum water arsenic concentrations determined have been 14.24, 24.19 and 1.44 μg/l, respectively. On the other hand, nine sediment samples of Raigón and Libertad Formations in Kiyú region were analysed and yielded median, maximum and minimum arsenic concentrations of 5.03, 9.82 and 1.18 ppm, respectively. This issue leads to the supposition that the population, as well as industrial and agricultural activities, are consuming water with arsenic concentrations over the national and international maximum recommended limit.Como una aproximación a la Geología Médica en Uruguay se presentan los resultados de un estudio sobre el estado del Sistema Acuífero Raigón en relación a la presencia de arsénico, en el entendido que es el acuífero más explotado en el país. En particular, el área cubierta por este trabajo es de unos 1800 km2 en un territorio con una población de unos 10,000 habitantes en el departamento de San José. La colecta de aguas del acuífero se realizó en perforaciones de la base de datos de PRENADER (Proyecto de Manejo de Recursos Naturales y Desarrollo del Riego) obteniéndose 37 muestras, y sobre 9 muestras de sedimentos tanto de la Formación Raigón como la suprayacente Libertad en afloramientos de la región de Kiyú. Los análisis fueron realizados mediante ICP-MS. Un 80% de las muestras de aguas analizadas mostraron contenidos mayores a los límites de la OMS (10 μg/l) y un 11% de las muestras superaron el límite de la OSE (20 μg/l). El valor medio, máximo y mínimo determinado en el caso del agua subterránea fue de 14.24, 24.19 and 1.44 μg/l, respectivamente. Por otro lado, las nueve muestras de sedimentos analizados mostraron concentraciones media, máxima y mínima de arsénico de 5.03, 9.82 and 1.18 ppm, respectivamente, descartándose en principio un origen geogénico.Cooperation between the University of the Republic (Uruguay) and CSIC from Spain (Ref. 2005UY0001). DINACYT-Uruguay, Project of the Technological Development Program PDT # 45/14 which included the doctoral thesis work of MSc. Rosario Guerequiz. CYTED Iberoarsen Network and the International Medical Geology Association contributed with scientific and technical support to improve the knowledge on environmental arsenic and health impacts, with a multidisciplinary approach in Uruguay. This work was performed under the Research Consolidated Groups SGR-2005-795 PEGEFA (Petrology and Geochemistry Basic and Applied) and SGR-2005-00589 (Mineral Resources), funded by AGAUR-DURSI, Generalitat de Catalunya.Peer reviewe

Role of Conserved Non-Coding Regulatory Elements in LMW Glutenin Gene Expression

Transcriptional regulation of LMW glutenin genes were investigated in-silico, using publicly available gene sequences and expression data. Genes were grouped into different LMW glutenin types and their promoter profiles were determined using cis-acting regulatory elements databases and published results. The various cis-acting elements belong to some conserved non-coding regulatory regions (CREs) and might act in two different ways. There are elements, such as GCN4 motifs found in the long endosperm box that could serve as key factors in tissue-specific expression. Some other elements, such as the AACA/TA motifs or the individual prolamin box variants, might modulate the level of expression. Based on the promoter sequences and expression characteristic LMW glutenin genes might be transcribed following two different mechanisms. Most of the s- and i-type genes show a continuously increasing expression pattern. The m-type genes, however, demonstrate normal distribution in their expression profiles. Differences observed in their expression could be related to the differences found in their promoter sequences. Polymorphisms in the number and combination of cis-acting elements in their promoter regions can be of crucial importance in the diverse levels of production of single LMW glutenin gene types

Allelic Variation, Alternative Splicing and Expression Analysis of Psy1 Gene in Hordeum chilense Roem. et Schult

Background: The wild barley Hordeum chilense Roem. et Schult. is a valuable source of genes for increasing carotenoid content in wheat. Tritordeums, the amphiploids derived from durum or common wheat and H. chilense, systematically show higher values of yellow pigment colour and carotenoid content than durum wheat. Phytoene synthase 1 gene (Psy1) is considered a key step limiting the carotenoid biosynthesis, and the correlation of Psy1 transcripts accumulation and endosperm carotenoid content has been demonstrated in the main grass species. Methodology/Principal findings: We analyze the variability of Psy1 alleles in three lines of H. chilense (H1, H7 and H16) representing the three ecotypes described in this species. Moreover, we analyze Psy1 expression in leaves and in two seed developing stages of H1 and H7, showing mRNA accumulation patterns similar to those of wheat. Finally, we identify thirtysix different transcripts forms originated by alternative splicing of the 59 UTR and/or exons 1 to 5 of Psy1 gene. Transcripts function is tested in a heterologous complementation assay, revealing that from the sixteen different predicted proteins only four types (those of 432, 370, 364 and 271 amino acids), are functional in the bacterial system. Conclusions/Significance: The large number of transcripts originated by alternative splicing of Psy1, and the coexistence of functional and non functional forms, suggest a fine regulation of PSY activity in H. chilense. This work is the first analysis of H. chilense Psy1 gene and the results reported here are the bases for its potential use in carotenoid enhancement in duru

Inocuidad de papas y boniatos: ¿es recomendable también comerlos con cáscara?.

En este artículo se presenta la metodología y los r resultados de la primera evaluación de la inocuidad química de hortalizas consumidas en el país, en particular para la papa y el boniato. La iniciativa deja a disposición una plataforma analítica para futuros programas de vigilancia de la inocuidad de estos vegetales con relación al contenido de arsénico, cadmio y plomo

Desarrollo de una metodología analítica para la determinación de Cd, Pb y As en frutas y hortalizas como una alternativa a los métodos estándar de análisis. [Development of an analytical methodology for the determination of Cd, Pb and As in fruits and vegetables as an alternative to standard methods of analysis].

RESUMEN.Las frutas y hortalizas pueden contener contaminantes que llegan al producto en cualquier punto de la cadena productiva. En este sentido, se debe controlar la acumulación de elementos potencialmente tóxicos como arsénico (As), cadmio (Cd) y plomo (Pb) para asegurar y controlar la inocuidad de estos alimentos.Con el objetivo de monitorear los contaminantes inorgánicos, de forma rápida, confiable y con métodos analíticos en acuerdo con los principios de la química ­verde, se desarrolló y validó una metodología para la extracción simultánea de estos elementos asistida con microondas, en un solo paso y utilizando ácido diluido.Se aplicó el método validado a cuatro productos: zanahoria, lechuga, manzana y tomate. Los parámetros de desempeño de esta metodología indicaron que resultó adecuada para monitorear estos alimentos tomando como referencia la reglamentación vigente y que todas las muestras analizadas cumplieron con los criterios establecidos. Esta metodología validada puede ser considerada como alternativa a los métodos estándar de análisis de As, Cd y Pb en este tipo de alimentos. El desarrollo de estas herramientas analíticas es de relevancia y deja disponible una plataforma analítica al servicio del sector productivo y de organismos de contralor nacional.ABSTRACT.Fruits and vegetables may contain contaminants that reach the product at any point in the production chain. In this sense, the accumulation of potentially toxic elements such as arsenic (As), cadmium (Cd) and lead (Pb) must be controlled to ensure food safety.In order to monitor inorganic pollutants, a fast and reliable analytical method also following the principles of green chemistry was developed and validated for simultaneous extraction of these elements using a microwave-assisted procedure, in a single step and with diluted acid. The validated method was applied in four products: carrot, lettuce, apple and tomato. The figures of merit of this methodology indicated that it was adequate to monitor these contaminants in the analyzed foods fulfilling with the current regulations. The developed method can be considered as an alternative to standard methods for the determination of As, Cd and Pb in these foods. These kinds of studies applied to monitor food safety are relevant and, in this case, an analytical platform is now available for the productive sector and national control agencies

A simple and economical ultrasound-assisted method for Cd and Pb extraction from fruits and vegetables for food safety assurance. [Open Access].

Ultrasound-assisted extraction (UAE) methods for food analysis are recognized as being in accordance with the principles of green analytical chemistry (GAC). Reference standard methods generally use microwave-assisted extraction (MAE) for sample digestion; however, the use of ultrasonication processes has many advantages. Herein, a simple, and economical method for the determination of Cd and Pb in fruits and vegetables for food safety monitoring is reported. This method was optimized using a standard reference material (SRM, spinach leaves) through a multivariate experimental design (optimal conditions: 0.5 g of sample, 15 min of sonication, and 20.00 mL of 2.5 mol L−1 HNO3) and subsequently validated. The limits of detection obtained were one or two orders of magnitude lower than those achieved with MAE, making this a promising technique for contaminants monitoring. The UAE method was then tested on vegetable samples (apples, carrots, tomatoes, and lettuce) obtained from commercial sources in Uruguay and a comparison was made with samples treated by MAE. Both processes yielded comparable results, and the levels of Cd and Pb in all samples were below the maximum allowed concentration (MAC) established by the World Health Organization (WHO). In addition, to provide insight into the mechanism by which the ultrasonic process aids extraction, confocal optical images of the surface of the SRM were obtained. The leaves were examined after treatment at different sonication times (5?20 min). The confocal microscopy images show the effects of the ultrasonic treatment on the plant tissue, including desaturation, erosion, and abrasion, which increased with increasing sonication time. In conclusion, the UAE method meets and overcome the requirements of a standard method for food safety assurance

Significant down-regulation of γ-gliadins has minor effect on gluten and starch properties of bread wheat

The contribution of gliadins to the baking performance of wheat has been widely discussed. In the present study we report the properties of the flours of fifteen transgenic wheat lines with γ-gliadins down-regulated by RNAi. Technological properties were assessed by sodium dodecyl sulfate sedimentation (SDSS) test, and rheological properties were characterized during mixing using the Mixolab ®. Changes in the proportions of gluten proteins, with significant increases of glutenins, were observed in transgenic lines. These changes did not affect the SDSS test in most of the transgenic lines. The dough strength of some transgenic lines was reduced as determined by the Mixolab ®. Changes in the starch behavior were also observed in the transgenic lines, in which lower values of torque were observed at the C3, C4 and C5 points of the mixing curve. The results reported here are important in understanding the role of γ-gliadins in the bread-making quality of flours. © 2012 Elsevier Ltd.This work was supported by the Spanish Comisión Interministerial de Ciencia y Tecnología (AGL2010-19643-C02-02 and TRA2009_0047), the European Regional Development Fund (FEDER) and Junta de Andalucía (Project P09AGR-4783).Peer Reviewe

Mixolab parameters of flour samples.

<p>Average values obtained in the 2010 and 2011 assays are shown for each transgenic and wild-type line. Means are significantly different to control as determined by Dunnett’s multiple comparison as follows: *<i>P</i><0.1; **<i>P</i><0.05; ***<i>P</i><0.01.</p