48 research outputs found

    Pressurized liquid extraction of caffeine and catechins from green tea leaves using ethyl lactate, water and ethyl lactate + water mixtures

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    Ethyl-lactate (ethyl 2-hydroxy-propanoate) is a bio-renewable agrochemical solvent, very suitable and environmental benign for food applications, permitted by the U.S. Food and Drug Administration as pharmaceutical and food additive. In previous work, the authors demonstrated that pressurized liquid extraction (PLE) using ethyl lactate is a suitable alternative to remove caffeine from vegetal materials, e.g. green coffee beans and green tea leaves. The solubility of caffeine in ethyl lactate + water mixtures, at ambient temperature and pressure, exhibits a substantial increase for 60:40% ethyl lactate + water mixtures (data reported in this work). This result motivated the analysis of the effect of the ethyl lactate + water mixtures for the decaffeination target. Furthermore, in the case of green tea, the removal of caffeine reducing the extraction of catechins is desirable due to the adverse effects of caffeine on health, while catechins are high valued functional food ingredients. Thus, the use of ethyl lactate, water and ethyl lactate + water mixtures to attain this objective, i.e. the removal of caffeine form green tea leaves minimizing the extraction of catechins, was studied in this work. PLE was carried out in the temperature range 373-473 K and using different ethyl lactate + water mixtures. Extraction yield and recovery of key bioactive compounds (caffeine and monomeric catechins) were determined and compared, and the caffeine/catechins selectivity of the different solvents employed was estimated. High extraction yields were obtained with a mixture containing 25:75% of ethyl lactate + water, with values around 1.5 and 3.5 times higher than, respectively, the yields obtained with water and ethyl lactate. Yet, pure ethyl lactate proved to be the most selective solvent to extract caffeine from green tea leaves, minimizing the co-extraction of catechins, with a caffeine/catechins selectivity of 2.8 to 5.5 in the range 373-423 K. At these temperatures, with short extraction times (20 min) the recovery of caffeine is in the range 53-76% but only 26-36% of catechins present in the tea leaves were removedThis work was financed thanks to AGL2011-29857-C03-01 (Ministerio de Economía y Competitividad) and ALIBIRD, S2013/ABI-2728 (Comunidad de Madrid) project

    Phytochemical and functional characterization of phenolic compounds from cowpea (Vigna unguiculata (l.) walp.) obtained by green extraction technologies

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    This work presents a green, downstream process, from extraction to phytochemical characterization and bioactivity testing, to obtain and evaluate the functional properties of phenolic compounds from cowpea (Vigna unguiculata (L.) Walp.) seeds and pods. Phenolic-rich extracts were obtained by pressurized liquid extraction (PLE). The main factors affecting the extraction conditions (temperature and solvent) were optimized in order to attain extracts with the highest extraction yield, antioxidant capacity, and total phenolic content. The optimal extraction conditions were 1:1 ethanol:water at 170◦C with one extraction cycle for seeds and three extraction cycles for pods. Phenolic compounds of optimal extract were analyzed by UHPLC-q-TOF-MS/MS (quadrupole-time of flight tandem MS). The obtained PLE-extracts exhibited higher phenolic content and antioxidant activity compared to conventional extraction procedures. The in vitro anti-neurodegenerative potential of extracts was measured through Acetylcholinesterase (AChE) inhibition assay. The results revealed the higher bioactivity observed in cowpea pod samples compared to seed extracts, which might be related to higher levels of quercetin and quercetin glycosides, kaempferol diglucoside, and other tetrahydroxylated flavones and flavonols identified in these samples. These results also provide an added-value benefit to the cultivation of this legume, considering the high potential of cowpea phenolic extracts as nutraceutical and functional ingredients in food formulations.Fil: Avanza, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Química Básica y Aplicada del Nordeste Argentino. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas Naturales y Agrimensura. Instituto de Química Básica y Aplicada del Nordeste Argentino; ArgentinaFil: Álvarez Rivera, Gerardo. Institute of Food Science Research; EspañaFil: Cifuentes, Alejandro. Institute of Food Science Research; EspañaFil: Mendiola, José A.. Institute of Food Science Research; EspañaFil: Ibáñez, Elena. Institute of Food Science Research; Españ

    Downstream processing of Isochrysis galbana: a step towards microalgal biorefinery

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    An algae-based biorefinery relies on the efficient use of algae biomass through its fractionation of several valuable/bioactive compounds that can be used in industry. If this biorefinery includes green platforms as downstream processing technologies able to fulfill the requirements of green chemistry, it will end-up with sustainable processes. In the present study, a downstream processing platform has been developed to extract bioactive compounds from the microalga Isochrysis galbana using various pressurized green solvents. Extractions were performed in four sequential steps using (1) supercritical CO2 (ScCO2), (2) ScCO2/ethanol (Gas Expanded Liquid, GXL), (3) pure ethanol, and (4) pure water as solvents, respectively. The residue of the extraction step was used as the raw material for the next extraction. Optimization of the ScCO2 extraction was performed by factorial design in order to maximize carotenoid extraction. During the second step, different percentages of ethanol were evaluated (15%, 45% and 75%) in order to maximize the extraction yield of fucoxanthin, the main carotenoid present in this alga; the extraction of polar lipids was also an aim. The third and fourth steps were performed with the objective of recovering fractions with high antioxidant activity, eventually rich in carbohydrates and proteins. The green downstream platform developed in this study produced different extracts with potential for application in the food, pharmaceutical and cosmetic industries. Therefore, a good approach for complete revalorization of the microalgae biomass is proposed, by using processes complying with the green chemistry principlesThe authors acknowledge funding from the EU MIRACLES project (7th Framework Program - Grant Agreement No. 613588). B.G.L. thanks MINECO (Ministerio de Economía y Competitividad) for her Juan de la Cierva postdoctoral research contract. M.H. thanks MINECO for his Ramón y Cajal postdoctoral research contract

    Recovering Bioactive Compounds from Olive Oil Filter Cake by Advanced Extraction Techniques

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    The potential of by-products generated during extra-virgin olive oil (EVOO) filtration as a natural source of phenolic compounds (with demonstrated bioactivity) has been evaluated using pressurized liquid extraction (PLE) and considering mixtures of two GRAS (generally recognized as safe) solvents (ethanol and water) at temperatures ranging from 40 to 175 °C. The extracts were characterized by high-performance liquid chromatography (HPLC) coupled to diode array detection (DAD) and electrospray time-of-flight mass spectrometry (HPLC-DAD-ESI-TOF/MS) to determine the phenolic-composition of the filter cake. The best isolation procedure to extract the phenolic fraction from the filter cake was accomplished using ethanol and water (50:50, v/v) at 120 °C. The main phenolic compounds identified in the samples were characterized as phenolic alcohols or derivatives (hydroxytyrosol and its oxidation product), secoiridoids (decarboxymethylated and hydroxylated forms of oleuropein and ligstroside aglycones), flavones (luteolin and apigenin) and elenolic acid derivatives. The PLE extraction process can be applied to produce enriched extracts with applications as bioactive food ingredients, as well as nutraceuticals

    Relationships between heavy metal concentrations in three different body fluids and male reproductive parameters: a pilot study

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    <p>Abstract</p> <p>Background</p> <p>Animal studies have shown the reproductive toxicity of a number of heavy metals. Very few human observational studies have analyzed the relationship between male reproductive function and heavy metal concentrations in diverse biological fluids.</p> <p>Methods</p> <p>The current study assessed the associations between seminal and hormonal parameters and the concentration of the 3 most frequent heavy metal toxicants (lead, cadmium and mercury) in three different body fluids. Sixty one men attending infertility clinics that participated in a case-control study to explore the role of environmental toxins and lifestyles on male infertility were analyzed. Concentration of lead, cadmium and mercury were measured in blood and seminal plasma and whole blood using anodic stripping voltammetry and atomic absorption spectrophotometry. Serum samples were analyzed for follicle-stimulating hormone, luteinizing hormone and testosterone. Semen analyses were performed according to World Health Organization criteria. Mann-Whitney test and Spearman's rank correlations were used for unadjusted analyses. Multiple linear regression models were performed controlling for age, body mass index and number of cigarettes per day.</p> <p>Results</p> <p>There were no significant differences between cases and controls in the concentrations of heavy metals in any of the three body fluids. In multivariate analyses using all subjects no significant associations were found between serum hormone levels and metal concentrations. However there was a significant positive association between the percentage of immotile sperms and seminal plasma levels of lead and cadmium.</p> <p>Conclusions</p> <p>Our results suggest that the presence of lead and cadmium in the reproductive tract of men may be related to a moderate alteration of their seminal parameters.</p

    Functional Proteomics Characterization of the Role of SPRYD7 in Colorectal Cancer Progression and Metastasis

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    SPRY domain-containing protein 7 (SPRYD7) is a barely known protein identified via spatial proteomics as being upregulated in highly metastatic-to-liver KM12SM colorectal cancer (CRC) cells in comparison to its isogenic poorly metastatic KM12C CRC cells. Here, we aimed to analyze SPRYD7&rsquo;s role in CRC via functional proteomics. Through immunohistochemistry, the overexpression of SPRYD7 was observed to be associated with the poor survival of CRC patients and with an aggressive and metastatic phenotype. Stable SPRYD7 overexpression was performed in KM12C and SW480 poorly metastatic CRC cells and in their isogenic highly metastatic-to-liver-KM12SM-and-to-lymph-nodes SW620 CRC cells, respectively. Upon upregulation of SPRYD7, in vitro and in vivo functional assays confirmed a key role of SPRYD7 in the invasion and migration of CRC cells and in liver homing and tumor growth. Additionally, transient siRNA SPRYD7 silencing allowed us to confirm in vitro functional results. Furthermore, SPRYD7 was observed as an inductor of angiogenesis. In addition, the dysregulated SPRYD7-associated proteome and SPRYD7 interactors were elucidated via 10-plex TMT quantitative proteins, immunoproteomics, and bioinformatics. After WB validation, the biological pathways associated with the stable overexpression of SPRYD7 were visualized. In conclusion, it was demonstrated here that SPRYD7 is a novel protein associated with CRC progression and metastasis. Thus, SPRYD7 and its interactors might be of relevance in identifying novel therapeutic targets for advanced CRC

    Production, chemical characterization, and sensory profile of a novel spirit elaborated from spent coffee ground

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    This study describes a process for the production of a spirit from spent coffee ground (SCG), the chemical composition, and sensory profile of this distillate. The process consisted in three steps starting with the extraction of aroma compounds by hydrothermal treatment of SCG, followed by the fermentation of this extract supplemented with sucrose to ethanol, and the fermented broth distillation. Seventeen volatile compounds were identified in the distillate (including alcohols, esters, aldehydes, and acids), all of them in concentrations able to promote pleasant characteristics to the product. Based on the chemical composition, \SCG\ spirit was considered as having organoleptic quality acceptable for human consumption. Twelve descriptors defined the sensory characteristics of this product, including clarity and brilliance (visual analysis), coffee, roasted, alcohol, elegance and frankly (olfactory analysis), bitter, astringent and pungent (gustatory analysis), and finesse (olfactory and gustatory analyses). Coffee was the most representative aroma by olfactory analysis. Based on the sensory analysis, \SCG\ spirit was considered as having features of a pleasant beverage, with smell and taste of coffee

    Epistemología histórica e historiografía

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    Ensayos cuyo tema gira sobre la historicidad de la razón científica que ahora es cuestionada desde la misma ciencia. Desde ella se puede seguir una línea desde Gaston Bachelard a Michel Foucault del lado de la reflexión francesa, y, del lado anglosajón, desde el giro lingüístico al programa fuerte de la Escuela de Edimburgo. Por todo esto no es azaroso que la epistemología histórica y la historiografía surjan simultáneamente a partir de la década de 1960. Obras tan significativas como la de Kuhn en el ámbito de la ciencia, o como las de Foucault, se inscriben en este momento. Comparten pues, esta misma preocupación: repensar las condiciones de posibilidad del conocimiento y las de la historiografía. El libro está dividido en dos partes. La primera contiene las reflexiones que incumben directamente a la epistemología histórica, y la segunda parte, las de historiografía. Ambas tienen en común la centralidad de la historicidad.Norma Durán R. A., coordinador

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Advanced analysis of nutraceuticals

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    17 páginas, 8 tablas, 6 figuras.-- El pdf del artículo es la versión de autor.In this article, we present a review work on different nutraceuticals found in natural matrices together with the analytical techniques used to identify and/or quantify them with special emphasis in the period January 2005–May 2010. The work is distributed according to the different families of nutraceuticals (lipids, vitamins, proteins, glycosides, phenolic compounds, etc.) discussing the analytical techniques employed for their determination (separation, spectroscopic, hyphenated techniques, etc.). Information about the claimed health promoting effects of the different families of nutraceuticals is also provided together with data on the natural matrices in which they can be found (e.g., fruits, vegetables, plants, microalgae, cereals, milk, etc.)Ministerio de Innovación (AGL2008-05108-C03-01 and CONSOLIDER INGENIO 2010 CSD2007-00063 FUN-C-FOOD), Comunidad de Madrid (Alibird)Peer reviewe
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