Evaluación del potencial nutracéutico de extractos de mora (Morus alba)

[ES] Las costumbres en la alimentación de los últimos años muestran un interés del consumidor por ciertos alimentos que, además de su propio valor nutritivo, también ayuden a mantener el estado general de salud del organismo, y a su vez puedan tener un efecto adicional de prevención y el tratamiento de enfermedades relacionadas con el daño oxidativo. Esto ha generado una nueva área de desarrollo de productos en la nutrición conocida como nutracéuticos. Los nutracéuticos pueden definirse como suplementos dietéticos concentrados elaborados a partir de sustancias bioactivas naturales derivadas de un alimento que aportan un beneficio para la salud. Se pueden encontrar comercializados en forma de cápsulas, jarabes, polvo, etc. La mora contiene gran cantidad de compuestos fitoquímicos que contribuyen a sus propiedades nutricionales y funcionales. Su extracción puede permitir su empleo como nutracéuticos o como nuevos ingredientes para la fortificación y formulación de otros alimentos, aumentando así su potencial antioxidante, y con ello los beneficios para la salud del consumidor. En este trabajo se obtendrán extractos de mora ricos en compuestos bioactivos hidrofílicos y lipofílicos y se estudiará principalmente el contenido en compuestos fenólicos y carotenoides como principales compuestos bioactivos presentes en esta fruta. Tras su caracterización se evaluará la contribución de estos compuestos a la actividad antioxidante total del producto. Además se estudiará el efecto del proceso de obtención del extracto en la estabilidad del mismo.[EN] An adequate and varied diet is important since numerous studies and recommendations relate a balanced diet with a healthier lifestyle and disease prevention. In this sense, fruits play a role because they have large amounts of antioxidant compounds, which are related to the prevention of significant pathologies. Mulberry belongs to the so called family of "forest fruits". This fruit has a long tradition in Chinese culture for its medicinal properties due to its high content of phytochemicals. However, its production is seasonal and its stability is very limited, only a small percentage of mulberries reaches the fresh market, most are frozen or canned. Therefore, it would be interesting to design a nutraceutical from mulberry extracts, for which freeze dried mulberry may be appropriated. However, the viability and stability of the nutraceutical depends on many factors, since the bioactive compounds may undergo different degradation reactions such as oxidation. The aim of this work was to study the application of freeze drying technology and gum arabic addition as encapsulant in the bioactive composition and antioxidant activity of mulberry extracts. To this purpose different extractions were performed with different solvents, in order to obtain a product rich in water-soluble (phenolics and vitamin C) and liposoluble (carotenoids) compounds. Furthermore antioxidant activity of the extracts was evaluated by DPPH, FRAP and ABTS methods. These extracts were dried and the influence of the process was assessed in the same parameters analyzed in extracts in solution. It has been found that freeze drying increased the extraction yield of phenolic compounds and carotenoids, but decreased the content of vitamin C and the antioxidant activity of the extracts. The antioxidant activity evaluated in the hydrophilic extracts was greater than in the lipophilic one. Vitamin C was the bioactive that better correlated with antioxidant capacity. Extract dehydration step decreased phenolic compounds 4% and vitamin C 9%. In general, the addition of gum arabic favoured the stability of the phytochemicals studied.Cervera March, J. (2016). Evaluación del potencial nutracéutico de extractos de mora (Morus alba). http://hdl.handle.net/10251/68962.TFG

Equilibrio de intercambio iónico en el ablandamiento de agua con resinas sulfónicas en forma sódica

Se ha esttrdiado el equilibrio de intercambio iónico Ca2+/Na+ con resina sulfónica (IMAC C-12) y en disoluciones de salinidad (0,010 N de Ca2+ y 0,019 N total) análoga a la del agua potabilizada de Barcelona procedente del rio Llobregat, cuyo análisis se efecfuó diariamente a lo largo del año 1978. Los resultados se discuten mediante análisis no lineal con diversos modelos de equilibrio, siendo la isoterma empírica de Rothrnund-Kornfeld y el modelo de Donnan los que mejor se ajustan, en contraste con lo inadecuado de la isoterma empírica de Freundlich y, sobre todo, del modelo de Langmuir, lo que permite explicar el equilibrio de intercambio a la luz de las hipótesis del modelo de membrana y no como fenómeno de adsorción superficial

Detection of DDT and carbaryl pesticides in honey by means of immunosensors based on high fundamental frequency quartz crystal microbalance (HFF-QCM)

[EN] BACKGROUND: In recent years there has been a concern about the presence of pesticides in honey because residues of DDT and carbaryl were found in honey samples. Traditional techniques, such as chromatography, reach the required limits of detection (LOD) but are not suitable for in situ implementation in the honey-packaging industry due to their high cost and the need for highly quali¿ed staff for routine operation. Biosensors offer simplicity, low cost, and easy handling for analytical purposes in food applications. RESULTS: Piezoelectric immunosensors based on high fundamental frequency quartz crystal microbalance (HFF-QCM) have been developed for the detection of carbaryl and DDT in honey. Biorecognition was based on competitive immunoassays in the conjugate-coated format, using monoclonal antibodies as speci¿c immunoreagents. The assay LODs attained by the HFF-QCM immunosensors were 0.05 ~gL¿1 for carbaryl and 0.24 ~gL¿1 for DDT, reaching a similar level of detectability to that of the usual reference techniques. The practical LODs in honey samples were 8 ~gkg¿1 for carbaryl and 24 ~gkg¿1 for DDT. The immunosensors¿ analytical performance allow the detection of these pesticides in honey at EU regulatory levels with good accuracy (recovery percentages ranging from 94% to 130% within the working range of each pesticide standard curve) and precision (coef¿cients of variation in the 9¿36% range). CONCLUSION: The proposed immunosensor is a promising analytical tool that could be implemented for quality control in the honey packaging industry, to simplify and to reduce the cost of the routine pesticide analysis in this appreciated natural food.This research was funded by the Spanish Ministry of Economy and Competitiveness with FEDER funds (AGL Project 2013-48646-R). L.C.C. was the recipient of a PhD fellowship from the European Social Fund and the Generalitat Valenciana (ACIF / 2016/132)Cervera-Chiner, L.; March, C.; Arnau Vives, A.; Jiménez Jiménez, Y.; Montoya, Á. (2020). Detection of DDT and carbaryl pesticides in honey by means of immunosensors based on high fundamental frequency quartz crystal microbalance (HFF-QCM). Journal of the Science of Food and Agriculture. 100(6):2468-2472. https://doi.org/10.1002/jsfa.10267S246824721006Blasco, C., Fernández, M., Pena, A., Lino, C., Silveira, M. I., Font, G., & Picó, Y. (2003). Assessment of Pesticide Residues in Honey Samples from Portugal and Spain. Journal of Agricultural and Food Chemistry, 51(27), 8132-8138. doi:10.1021/jf034870mRISSATO, S., GALHIANE, M., DEALMEIDA, M., GERENUTTI, M., & APON, B. (2007). Multiresidue determination of pesticides in honey samples by gas chromatography–mass spectrometry and application in environmental contamination. Food Chemistry, 101(4), 1719-1726. doi:10.1016/j.foodchem.2005.10.034Ruiz-Toledo, J., Vandame, R., Castro-Chan, R., Penilla-Navarro, R., Gómez, J., & Sánchez, D. (2018). Organochlorine Pesticides in Honey and Pollen Samples from Managed Colonies of the Honey Bee Apis mellifera Linnaeus and the Stingless Bee Scaptotrigona mexicana Guérin from Southern, Mexico. Insects, 9(2), 54. doi:10.3390/insects9020054Juan-Borrás, M., Domenech, E., & Escriche, I. (2016). Mixture-risk-assessment of pesticide residues in retail polyfloral honey. Food Control, 67, 127-134. doi:10.1016/j.foodcont.2016.02.051Marrazza, G. (2014). Piezoelectric Biosensors for Organophosphate and Carbamate Pesticides: A Review. Biosensors, 4(3), 301-317. doi:10.3390/bios4030301March, C., García, J. V., Sánchez, Á., Arnau, A., Jiménez, Y., García, P., … Montoya, Á. (2015). High-frequency phase shift measurement greatly enhances the sensitivity of QCM immunosensors. Biosensors and Bioelectronics, 65, 1-8. doi:10.1016/j.bios.2014.10.001Cervera-Chiner, L., Juan-Borrás, M., March, C., Arnau, A., Escriche, I., Montoya, Á., & Jiménez, Y. (2018). High Fundamental Frequency Quartz Crystal Microbalance (HFF-QCM) immunosensor for pesticide detection in honey. Food Control, 92, 1-6. doi:10.1016/j.foodcont.2018.04.026Montoya, A., March, C., Montagut, Y., Moreno, M., Manclus, J., Arnau, A., … Torres, R. (2017). A High Fundamental Frequency (HFF)-based QCM Immunosensor for Tuberculosis Detection. Current Topics in Medicinal Chemistry, 17(14), 1623-1630. doi:10.2174/1568026617666161104105210Rawson, A., Venu, S., Santhi, K., Paranthaman, R., & Sureshkumar, K. (2019). Liquid chromatography–mass spectrometry/mass spectrometry method development for the determination of carbaryl residue in honey. Pharmacognosy Magazine, 15(64), 205. doi:10.4103/pm.pm_641_18Abad, A., Primo, J., & Montoya, A. (1997). Development of an Enzyme-Linked Immunosorbent Assay to Carbaryl. 1. Antibody Production from Several Haptens and Characterization in Different Immunoassay Formats. Journal of Agricultural and Food Chemistry, 45(4), 1486-1494. doi:10.1021/jf9506904Abad, A., Manclús, J. J., Mojarrad, F., Mercader, J. V., Miranda, M. A., Primo, J., … Montoya, A. (1997). Hapten Synthesis and Production of Monoclonal Antibodies to DDT and Related Compounds. Journal of Agricultural and Food Chemistry, 45(9), 3694-3702. doi:10.1021/jf9704219González-Martínez, M. A., Morais, S., Puchades, R., Maquieira, A., Abad, A., & Montoya, A. (1997). Monoclonal Antibody-Based Flow-Through Immunosensor for Analysis of Carbaryl. Analytical Chemistry, 69(14), 2812-2818. doi:10.1021/ac961068tMarch, C., Manclús, J. J., Jiménez, Y., Arnau, A., & Montoya, A. (2009). A piezoelectric immunosensor for the determination of pesticide residues and metabolites in fruit juices. Talanta, 78(3), 827-833. doi:10.1016/j.talanta.2008.12.058Mauriz, E., Calle, A., Manclús, J. J., Montoya, A., Hildebrandt, A., Barceló, D., & Lechuga, L. M. (2007). Optical immunosensor for fast and sensitive detection of DDT and related compounds in river water samples. Biosensors and Bioelectronics, 22(7), 1410-1418. doi:10.1016/j.bios.2006.06.016Sapozhnikova, Y., Simons, T., & Lehotay, S. J. (2015). Evaluation of a Fast and Simple Sample Preparation Method for Polybrominated Diphenyl Ether (PBDE) Flame Retardants and Dichlorodiphenyltrichloroethane (DDT) Pesticides in Fish for Analysis by ELISA Compared with GC-MS/MS. Journal of Agricultural and Food Chemistry, 63(18), 4429-4434. doi:10.1021/jf505651gSun, J., Dong, T., Zhang, Y., & Wang, S. (2010). Development of enzyme linked immunoassay for the simultaneous detection of carbaryl and metolcarb in different agricultural products. Analytica Chimica Acta, 666(1-2), 76-82. doi:10.1016/j.aca.2010.03.051Mauriz, E., Calle, A., Abad, A., Montoya, A., Hildebrandt, A., Barceló, D., & Lechuga, L. M. (2006). Determination of carbaryl in natural water samples by a surface plasmon resonance flow-through immunosensor. Biosensors and Bioelectronics, 21(11), 2129-2136. doi:10.1016/j.bios.2005.10.01

High Fundamental Frequency Quartz Crystal Microbalance (HFF-QCM) immunosensor for pesticide detection in honey

[EN] Quantification of chemical residues in honey is a market requirement to ensure consumer safety. The most common method used to analyze these compounds is the LC/MS/MS methodology, which requires highly qualified technicians and a tedious pre-treatment of the sample. The honey-packaging industry needs cheaper and faster alternatives for routine control. HFF-QCM (High Fundamental Frequency Quartz Crystal Microbalance) sensors are becoming a good option due to their high sensitivity, fast detection and low cost, while avoiding complex sample pre-treatment. The HFF-QCM technology is based on piezoelectric sensors with frequencies in the range from several tenths of MHz to hundreds of MHz. In this work a 100 MHz HFF-QCM sensor was used in a monoclonal antibody-based competitive immunoassay for specific bio-recognition of carbaryl pesticide as testing contaminant. The work intends to validate the use of HFF-QCM technology, in comparison with liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique, for the detection of contaminants in honey. For this purpose, the validation criteria required by SANCO 12571/2013 guidance document were considered. The precision and accuracy (recovery) of both methods were determined by comparison of 5 replicates at 4 different concentrations (from 0 to 100 ¿g/kg) using the same honey matrix. HFF-QCM technology showed good accuracy, with recovery percentages always between 110 and 120%. As regards to precision, HFF-QCM coefficients of variation (CV) were around 10% higher than those recommended by GC SANCO 12571/2013. HFF-QCM limits of detection (LOD) and quantification (LOQ) were in the same order of magnitude as those for LC-MS/MS, which allows the analysis of carbaryl residues in honey under the established maximum residue limits (MRL), without sample pre-treatment. These results show that biosensors based on HFF-QCM technology has become a serious alternative to the traditional analytical techniques for food quality and safety applications.The authors are grateful for financial support from the Ministry of Economy and Competitiveness of Spain under the project AGL2013-48646-R. We also want to thank “Generalitat Valenciana” for the financial support to hire research personnel through the grant “Ayudas para la contratación de personal investigador en formación de carácter predoctoral” to carry out this research (DOC Num.7615/15.09.2015).Cervera-Chiner, L.; Juan Borrás, MDS.; March, C.; Arnau Vives, A.; Escriche Roberto, MI.; Montoya, Á.; Jiménez Jiménez, Y. (2018). High Fundamental Frequency Quartz Crystal Microbalance (HFF-QCM) immunosensor for pesticide detection in honey. Food Control. 92:1-6. https://doi.org/10.1016/j.foodcont.2018.04.026S169

Evaluation of turbulent dissipation rate retrievals from Doppler Cloud Radar

Turbulent dissipation rate retrievals from cloud radar Doppler velocity measurements are evaluated using independent, in situ observations in Arctic stratocumulus clouds. In situ validation data sets of dissipation rate are derived using sonic anemometer measurements from a tethered balloon and high frequency pressure variation observations from a research aircraft, both flown in proximity to stationary, ground-based radars. Modest biases are found among the data sets in particularly low- or high-turbulence regimes, but in general the radar-retrieved values correspond well with the in situ measurements. Root mean square differences are typically a factor of 4-6 relative to any given magnitude of dissipation rate. These differences are no larger than those found when comparing dissipation rates computed from tetheredballoon and meteorological tower-mounted sonic anemometer measurements made at spatial distances of a few hundred meters. Temporal lag analyses suggest that approximately half of the observed differences are due to spatial sampling considerations, such that the anticipated radar-based retrieval uncertainty is on the order of a factor of 2-3. Moreover, radar retrievals are clearly able to capture the vertical dissipation rate structure observed by the in situ sensors, while offering substantially more information on the time variability of turbulence profiles. Together these evaluations indicate that radar-based retrievals can, at a minimum, be used to determine the vertical structure of turbulence in Arctic stratocumulus clouds

Radon and material radiopurity assessment for the NEXT double beta decay experiment

The Neutrino Experiment with a Xenon TPC (NEXT), intended to investigate the neutrinoless double beta decay using a high-pressure xenon gas TPC filled with Xe enriched in 136Xe at the Canfranc Underground Laboratory in Spain, requires ultra-low background conditions demanding an exhaustive control of material radiopurity and environmental radon levels. An extensive material screening process is underway for several years based mainly on gamma-ray spectroscopy using ultra-low background germanium detectors in Canfranc but also on mass spectrometry techniques like GDMS and ICPMS. Components from shielding, pressure vessel, electroluminescence and high voltage elements and energy and tracking readout planes have been analyzed, helping in the final design of the experiment and in the construction of the background model. The latest measurements carried out will be presented and the implication on NEXT of their results will be discussed. The commissioning of the NEW detector, as a first step towards NEXT, has started in Canfranc; in-situ measurements of airborne radon levels were taken there to optimize the system for radon mitigation and will be shown too.Comment: Proceedings of the Low Radioactivity Techniques 2015 workshop (LRT2015), Seattle, March 201

Issues and Challenges in Orbital-free Density Functional Calculations

Solving the Euler equation which corresponds to the energy minimum of a density functional expressed in orbital-free form involves related but distinct computational challenges. One is the choice between all-electron and pseudo-potential calculations and, if the latter, construction of the pseudo-potential. Another is the stability, speed, and accuracy of solution algorithms. Underlying both is the fundamental issue of satisfactory quality of the approximate functionals (kinetic energy and exchange-correlation). We address both computational issues and illustrate them by some comparative performance testing of our recently developed modified-conjoint generalized gradient approximation kinetic energy functionals. Comparisons are given for atoms, diatomic molecules, and some simple solids.Comment: submitted to Computer Physics Communication

An improved measurement of electron-ion recombination in high-pressure xenon gas

We report on results obtained with the NEXT-DEMO prototype of the NEXT-100 high-pressure xenon gas time projection chamber (TPC), exposed to an alpha decay calibration source. Compared to our previous measurements with alpha particles, an upgraded detector and improved analysis techniques have been used. We measure event-by-event correlated fluctuations between ionization and scintillation due to electron-ion recombination in the gas, with correlation coeffcients between -0.80 and -0.56 depending on the drift field conditions. By combining the two signals, we obtain a 2.8% FWHM energy resolution for 5.49 MeV alpha particles and a measurement of the optical gain of the electroluminescent TPC. The improved energy resolution also allows us to measure the specific activity of the radon in the gas due to natural impurities. Finally, we measure the average ratio of excited to ionized atoms produced in the xenon gas by alpha particles to be 0:561 0:045, translating into an average energy to produce a primary scintillation photon ofWex = (39:2 3:2) eV.This work was supported by the following agencies and institutions: the European Research Council under the Advanced Grant 339787-NEXT; the Ministerio de Economia y Competitividad of Spain under grants CONSOLIDER-Ingenio 2010 CSD2008-0037 (CUP), FPA2009-13697-C04 and FIS2012-37947-C04; the Director, Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under contract no. DE-AC02-05CH11231; and the Portuguese FCT and FEDER through the program COMPETE, project PTDC/FIS/103860/2008.Serra, L.; Sorel, M.; Alvarez, V.; Borges, FIG.; Camargo, M.; Carcel, S.; Cebrian, S.... (2015). An improved measurement of electron-ion recombination in high-pressure xenon gas. Journal of Instrumentation. 10:1-19. https://doi.org/10.1088/1748-0221/10/03/P03025S1191

Background rejection in NEXT using deep neural networks

[EN] We investigate the potential of using deep learning techniques to reject background events in searches for neutrinoless double beta decay with high pressure xenon time projection chambers capable of detailed track reconstruction. The differences in the topological signatures of background and signal events can be learned by deep neural networks via training over many thousands of events. These networks can then be used to classify further events as signal or background, providing an additional background rejection factor at an acceptable loss of efficiency. The networks trained in this study performed better than previous methods developed based on the use of the same topological signatures by a factor of 1.2 to 1.6, and there is potential for further improvement.The NEXT Collaboration acknowledges support from the following agencies and institutions: the European Research Council (ERC) under the Advanced Grant 339787-NEXT; the Ministerio de Economia y Competitividad of Spain and FEDER under grants CONSOLIDER-Ingenio 2010 CSD2008-0037 (CUP), FIS2014-53371-C04 and the Severo Ochoa Program SEV-2014-0398; GVA under grant PROMETEO/2016/120. Fermilab is operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy. JR acknowledges support from a Fulbright Junior Research Award.Renner, J.; Farbin, A.; Muñoz Vidal, J.; Benlloch-Rodríguez, J.; Botas, A.; Ferrario, P.; Gómez-Cadenas, J.... (2017). Background rejection in NEXT using deep neural networks. Journal of Instrumentation. 12. https://doi.org/10.1088/1748-0221/12/01/T01004S1