279 research outputs found

    Efecto de las variables del proceso sobre el rendimiento y la calidad del aceite de almendra de yerivá (Syagrus romanzoffiana) mediante extracción acuosa

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    The fruit from jerivá (Syagrus romanzoffiana) has a kernel which is rich in oil, and has a pleasant smell that reminds one of coconut. It is rich in monounsaturated and saturated fatty acids, in addition to bioactive compounds. In this work, the effect of process variables on the yield and quality of jerivá kernel oil from aqueous extraction was evaluated using response surface methodology. The variables pH, time and temperature influenced the yield and the quality of the oil. High pH and time, along with mild temperature were suitable conditions to extract jerivá kernel oil by aqueous extraction, but excessively high pH, temperature and time negatively impacted the oil’s quality. pH was the only variable that significantly influenced free acidity, with a decrease in free acidity with the increase in pH. On the other hand, the increase in pH, time and temperature increased the peroxide value, which limited some conditions for obtaining jerivá kernel oil by aqueous extraction. The optimal conditions were found to be an extraction at pH 12, 25 °C and 60 minutes, which resulted in a yield of 39%, free acidity of 0.2% and a peroxide value of 5.8 meqO2·kg-1. Aqueous extraction yielded more unsaturated oil than that extracted with hexane, in addition to a higher proportion of caproic, oleic and linoleic acids, thus improving its nutritional characteristics and health benefits, despite decreasing its oxidative stability.La fruta de yerivá (Syagrus romanzoffiana) tiene un grano rico en aceite, que tiene un olor agradable que recuerda al coco, es rico en ácidos grasos monoinsaturados y saturados, además de compuestos bioactivos. En este trabajo, se evaluó el efecto de las variables del proceso sobre el rendimiento y la calidad del aceite de grano de yerivá a partir de la extracción acuosa utilizando la metodología de superficie de respuesta. Las variables pH, tiempo y temperatura influyeron en el rendimiento y la calidad del aceite. pH alto, elevado tiempo y temperatura suave fueron las condiciones adecuadas para extraer el aceite de grano de yerivá mediante extracción acuosa. Sin embargo, el pH, la temperatura y el tiempo excesivamente altos impactaron negativamente en la calidad del aceite. El pH fue la única variable que influyó significativamente en la acidez libre, con una disminución de la acidez con el aumento del pH. Por otra parte, el aumento del pH, el tiempo y la temperatura aumentaron el valor del peróxido, lo que limitó algunas condiciones para obtener aceite de grano de yerivá por extracción acuosa. Se encontró que la condición óptima fue una extracción a pH 12, 25 °C y 60 minutos, lo que resultó en un rendimiento del 39%, una acidez libre del 0,2% y un valor de peróxido de 5,8 meqO2·kg−1. La extracción acuosa produjo más aceite insaturado que el extraído con hexano, además de una mayor proporción de caproico, oleico y linoleico, mejorando sus características nutricionales y beneficios para la salud, a pesar de disminuir su estabilidad oxidativa

    Optimización de superficie de respuesta de múltiples objetivos en la extracción acuosa de aceite de semilla de macauba

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    Macauba (Acrocomia aculeata) is a promising tropical palm for the production of vegetable oil for both the food and non-food sectors. In this work, a multi-target response surface optimization of the aqueous extraction of Macauba kernel oil aimed to maximize the oil yield and minimize the free acidy and peroxide value. High yield was achieved at a high pH, long extraction periods and moderate temperatures, but these conditions contributed to elevating the peroxide value of the oil. On the other hand, pH presented the only significant effect on the oil’s acidity, which decreased with the increase in pH in the aqueous medium. Therefore, the multi-target response surface optimization based on a desirability approach showed that pH 11, room temperature (25 °C) and a 60 min agitation time was preferred to obtain high yield and low free acidity and peroxide values. These conditions resulted in 30% yield (63.1% of the yield obtained by solvent extraction), 0.3% free acidity, and a peroxide value of 2.9 meqO2/kg. The oil from the optimized aqueous extraction had a higher saturated fatty acid content compared to that from solvent extraction, especially fatty acids with < 14 carbon atoms, which can make the oil harder and more useful for producing special fats for specific food applications.La macauba (Acrocomia aculeata) es una prometedora palma tropical para la producción de aceite vegetal para los sectores alimenticio y no alimentario. En este trabajo, una optimización de superficie de respuesta de múltiples objetivos en la extracción acuosa de aceite de semilla de macauba tuvo como objetivo maximizar el rendimiento del aceite y minimizar el valor de acidez libre y peróxidos. Se logró un alto rendimiento a pH alto, tiempos prolongados y temperaturas moderadas, pero estas condiciones contribuyeron a elevar el índice de peróxido del aceite. Por otro lado, el pH presentó como único efecto significativo sobre la acidez del aceite, la disminución con el aumento del pH en el medio acuoso. Por lo tanto, la optimización de la superficie de respuesta de múltiples objetivos basada en un enfoque de idoneidad mostró que se prefería pH 11, temperatura ambiente (25 °C) y un tiempo de agitación de 60 minutos para obtener un alto rendimiento y bajos valores de acidez libre y peróxido. Estas condiciones dieron como resultado un rendimiento del 30% (63,1% del rendimiento obtenido por extracción con disolvente), un 0,3% de acidez libre y un índice de peróxido de 2,9 meqO2/kg. El aceite de la extracción acuosa optimizada tenía un mayor contenido de ácidos grasos saturados en comparación con el de la extracción con solventes, especialmente de ácidos grasos con < 14 átomos de carbono, lo que puede hacer que el aceite sea más duro y útil para producir grasas especiales para aplicaciones alimentarias específicas

    Nutritional Evaluation Of Children With Chronic Cholestatic Disease

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    Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)To evaluate the nutritional status of children with persistent cholestasis and to compare the anthropometric indices between children with and without liver cirrhosis and children with and without jaundice. Methods Children with persistent cholestasis, i.e. increased direct bilirrubin or changes in the canalicular enzyme gamma-glutamyl transferase (GGT), were included. The anthropometric measures were weight (W), height or length (H), arm circumference (AC), triceps skinfold thickness (TST), arm muscle circumference (AMC), and body mass index (BMI). Results Ninety-one children with cholestasis, with current median age of 12 months, were evaluated. W/age (A) and H/A indices below -2 Z-scores were observed in 33% and 30.8% of patients, respectively. Concerning the W/H index and BMI, only 12% and 16% of patients, respectively, were below -2 Z-scores. Regarding AC, 43.8% of 89 evaluated patients had some depletion. Observing the TST, 64% of patients had depletion, and 71.1% of the 45 evaluated patients had some degree of depletion regarding the ACM index. Conclusion Evaluation using weight in patients with chronic liver diseases may overestimate the nutritional status due to visceromegaly, subclinical edema, or ascites. Indices that correlate weight and height, such as W/H and BMI, may also not show depletion because of the chronic condition in which there are depletion of both weight and height. TST, AC, and ACM are parameters that better estimate nutritional status and should be part of the management of patients with liver diseases and cholestasis. © 2015 Sociedade Brasileira de Pediatria.922197205CNPq, Conselho Nacional de Desenvolvimento Científico e TecnológicoConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Population overlap and habitat segregation in wintering Black-tailed Godwits Limosa limosa

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    Distinct breeding populations of migratory species may overlap both spatially and temporally, but differ in patterns of habitat use. This has important implications for population monitoring and conservation. To quantify the extent to which two distinct breeding populations of a migratory shorebird, the Black-tailed Godwit Limosa limosa, overlap spatially, temporally and in their use of different habitats during winter. We use mid-winter counts between 1990 and 2001 to identify the most important sites in Iberia for Black-tailed Godwits. Monthly surveys of estuarine mudflats and rice-fields at one major site, the Tejo estuary in Portugal in 2005-2007, together with detailed tracking of colour-ringed individuals, are used to explore patterns of habitat use and segregation of the Icelandic subspecies L. l. islandica and the nominate continental subspecies L. l. limosa. In the period 1990-2001, over 66 000 Black-tailed Godwits were counted on average in Iberia during mid-winter (January), of which 80% occurred at just four sites: Tejo and Sado lower basins in Portugal, and Coto Dontildeana and Ebro Delta in Spain. Icelandic Black-tailed Godwits are present throughout the winter and forage primarily in estuarine habitats. Continental Black-tailed Godwits are present from December to March and primarily use rice-fields. Iberia supports about 30% of the Icelandic population in winter and most of the continental population during spring passage. While the Icelandic population is currently increasing, the continental population is declining rapidly. Although the estuarine habitats used by Icelandic godwits are largely protected as Natura 2000 sites, the habitat segregation means that conservation actions for the decreasing numbers of continental godwits should focus on protection of rice-fields and re-establishment of freshwater wetlands

    Ventricular volume expansion in presymptomatic genetic frontotemporal dementia

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    Objective: To characterize the time course of ventricular volume expansion in genetic frontotemporal dementia (FTD) and identify the onset time and rates of ventricular expansion in presymptomatic FTD mutation carriers. Methods: Participants included patients with a mutation in MAPT, PGRN, or C9orf72, or first-degree relatives of mutation carriers from the GENFI study with MRI scans at study baseline and at 1 year follow-up. Ventricular volumes were obtained from MRI scans using FreeSurfer, with manual editing of segmentation and comparison to fully automated segmentation to establish reliability. Linear mixed models were used to identify differences in ventricular volume and in expansion rates as a function of time to expected disease onset between presymptomatic carriers and noncarriers. Results: A total of 123 participants met the inclusion criteria and were included in the analysis (18 symptomatic carriers, 46 presymptomatic mutation carriers, and 56 noncarriers). Ventricular volume differences were observed 4 years prior to symptom disease onset for presymptomatic carriers compared to noncarriers. Annualized rates of ventricular volume expansion were greater in presymptomatic carriers relative to noncarriers. Importantly, time-intensive manually edited and fully automated ventricular volume resulted in similar findings. Conclusions: Ventricular volume differences are detectable in presymptomatic genetic FTD. Concordance of results from time-intensive manual editing and fully automatic segmentation approaches support its value as a measure of disease onset and progression in future studies in both presymptomatic and symptomatic genetic FTD
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