1,423 research outputs found
Phytochemical characterization of Borago officinalis L. and Centaurea cyanus L. during flower development
The present work details the nutritional and chemical compositions of borage and centaurea, at three flowering
stages. Water was the main constituent, followed by total dietary fiber. Both flowers showed statistically different
(p < 0.05) nutritional and chemical profiles, although in both, polyunsaturated fatty acids (PUFAs)
(mainly linoleic and α-linolenic acids), free sugars (3.9–28.9% dw as fructose, glucose, and sucrose), tocopherols
(with the major contribution of α-tocopherol from 1.24 to 2.75 mg/100 g dw), carotenoids (0.2–181.4 mg/100 g
dw, mainly as lutein), and organic acids (6.1–14.4 g/100 g dw, mainly malic, succinic, and citric acids) were
quantified. Concerning flowering, significant differences (p < 0.05) were found for some components, particularly
carotenoids; however, no specific trend was observed in either of the two flower species. Thus, the
present study shows that each floThe authors acknowledge the Portuguese Foundation for Science
and Technology (FCT, Portugal) for the financial support provided by
the research grant SFRH/BD/95853/2013 to Luana Fernandes and
FCT/MEC for the financial support to QOPNA research Unit (FCT UID/
QUI/00062/2013) and LAQV Research Unit (UID/QUI/50006/2013
-POCI/01/0145/FEDER/007265) through national funds and co-financed
by the FEDER, within the PT2020 Partnership Agreement.
Furthermore, the authors are grateful to the Foundation for Science and
Technology (FCT, Portugal) and FEDER under Programme PT2020 for
financial support to CIMO (UID/AGR/00690/2013).info:eu-repo/semantics/publishedVersio
Physico-chemical and sensory characteristics of jellies made from seven grapevine (Vitis vinifera L.) varieties
Jellies of seven grapevine varieties were physico-chemical and sensorial characterized for the first time. Jellies differed significantly in moisture and ash contents, colour, pH, acidity and antioxidant activities. 'Tinta Carvalha' was the darkest and redness jelly, showing the highest antioxidant activity. Regarding sensory characteristics, no significant differences in the appearance, taste, sweetness, acidity and global assessment were observed among jellies. Nevertheless, these attributes were positively evaluated. In conclusion, the production of different jellies will allow the valorisation of grapevine varieties with less potential for wine production, helping to preserve biodiversity, and be an economic alternative to grape producers who may elaborate an enjoyable product with interesting bioactivity.Authors are grateful to POCTEP - Programa de
Cooperação Transfronteiriça Espanha - Portugal
for financial support (Project “RED/AGROTEC – Experimentation network and transfer for development of agricultural and agro industrial
sectors between Spain and Portugal).info:eu-repo/semantics/publishedVersio
Composição em ácidos gordos e vitamina E de óleos de sementes de uvas de dez castas portuguesas
O presente estudo teve como objetivo avaliar a vitamina E (tocoferóis e tocotrienóis) e os
ácidos gordos em óleos de semente de uva de dez castas portuguesas com o intuito de
aumentar o potencial e valorizar a exploração destes resíduos industriais. Os resultados
mostraram que os óleos de semente de uva são uma fonte potencialyde -tocotrienol (499-
1575 mg/kg), a-tocoferol (85,5-244 mg/kg) e a -tocotrienol (69-319 mg/kg), sendo o ytocotrienol
o mais comum. No que diz respeito à composição dos ácidos gordos, o linole ico
(C 18:2cc), oleico (C 18: I ), palmítico (C 16:0) e esteárico (C 18:0) foram os predominantes. Os
óleos de semente de uva demonstraram ser uma boa fonte de ácidos gordos polinsaturados
(PUF A) (63,64-73,53%), enquanto os ácidos gordos monoinsaturados (MUF A) e saturados
(SFA) variaram entre 14,19-2 1,29 e 11 ,64-1 4,94%, respetivamente. Em suma, o presente
trabalho demonstrou que os óleos extraídos a partir de sementes de castas de uvas portuguesas
apresentam uma composição adequada para poderem ser incorporados em outros produtos
alimentares.
O presente estudo teve como objetivo avaliar à vitamina E (tocoferóis e tocotrienóis) e os ácidos gordos em óleos de semente de uva de dez tradicionais castas portuguesas - Aragonês, Cornifesto, Marufo, Periquita, Tinta Barroca, Tinta Carvalha, Touriga Cão, Touriga Francesa, Touriga Nacional e Trincadeira Preta, com o intuito de aumentar o potencial e valorizar a exploração destes resíduos industriais.
Os resultados mostraram que os óleos de semente de uva são uma boa fonte de γ-tocotrienol (499-1575 mg/kg), α-tocoferol (85,5-244 mg/kg) e α-tocotrienol (69-319 mg/kg), sendo γ-tocotrienol o mais comum. No que diz respeito, a composição dos ácidos gordos o linoleico (C18:2cc), oleico (C18:1), palmítico (C16:0) e esteárico (C18:0) foram os mais predominantes. Os óleos de semente de uva demonstraram ser uma boa fonte de ácidos gordos polinsaturados (PUFA) (63,64 -73,53%), enquanto que os ácidos gordos monoinsaturados (MUFA) e saturados (SFA) variaram entre 14,19-21,29 e 11,64-14,94%, respectivamente. Segundo, as análises de cluster realizadas aos ácidos gordos e vitamina E obtiveram-se quatro grupos homogéneos.
Em suma, o presente trabalho demonstrou que as sementes de castas tradicionais de uvas portuguesas podem ser reutilizas e seus óleos incorporados em outros produtos alimentares, tendo em conta os compostos detectados que são referidos na literatura como tendo efeitos positivos na saúde humana
A Proposal for New Evaluation Metrics and Result Visualization Technique for Sentiment Analysis Tasks
Proceedings of: 4th International Conference of the CLEF Initiative (CLEF 2013). 4th International Conference of the CLEF Initiative (CLEF 2013). Valencia, Spain,
September 23-26, 2013.In this paper we propound the use of a number of entropybased metrics and a visualization tool for the intrinsic evaluation of Sentiment and Reputation Analysis tasks. We provide a theoretical justification for their use and discuss how they complement other accuracybased metrics. We apply the proposed techniques to the analysis of TASS-SEPLN and RepLab 2012 results and show how the metric is effective for system comparison purposes, for system development and postmortem evaluation.FJVA and JCdA are supported by EU FP7 project LiMoSINe (contract 288024). CPM has been partially supported by the Spanish Government-Comisión Interministerial de Ciencia y Tecnología project TEC2011-26807 for this paper.Publicad
Caracterização da fração lipídica de 28 amostras de cacau de São Tomé e Príncipe
No presente trabalho pretendeu-se caracterizar a fração lipídica de amostras de cacau presentes em São Tomé e Príncipe, tendo sido analisadas, no total, 28 amostras em relação à sua composição em ácidos gordos e vitamina E. No que respeita ao teor total de gordura, este variou entre 16,4 e 29,1%, existindo diferenças significativas entre as amostras (p<0,01). Também na composição em ácidos gordos se detetaram diferenças entre os óleos extraídos. Contudo, os óleos extraídos foram maioritariamente constituídos por três ácidos gordos em proporções semelhantes, nomeadamente o ácido palmítico (C16:0), o ácido esteárico (C18:0) e o ácido oleico (C 18:1). De entre os restantes ácidos gordos identificados, refira-se a presença do ácido linoleico (C18:2). Em termos gerais, os ácidos gordos saturados (SFA) foram os mais abundantes (61,4 a 65,6%), seguidos dos monoinsaturados (MUFA) (31,4 a 35,6 %) e polinsaturados (PUFA) (2,4 a 3,6%). Adicionalmente, o óleo de cacau demonstrou ser uma fonte de antioxidantes naturais, nomeadamente, tocoferóis. Foram detetados e quantificados o a-, g- e d-tocoferol. O mais abundante foi o g-tocoferol, tendo variado entre os 22, 3 e 47,6 mg/100 g de óleo, seguido do a-tocoferol (3,0-6,6 mg/100g de óleo) e d-tocoferol.info:eu-repo/semantics/publishedVersio
Edible flowers: a nutritional perspective
As flores comestíveis têm sido usadas na culinária de diversos países, tendo hoje em dia, o seu uso despertado a atenção com o intuito de melhorar a aparência, sabor e valor estético de pratos, aspetos que o consumidor aprecia e valoriza. No entanto, os consumidores também exigem alimentos com propriedades benéficas para a saúde, procurando produtos com qualidade nutricional interessante. Nesse sentido, o presente documento pretende abordar a composição nutricional de algumas flores comestíveis, incluindo os macro e micronutrientes, bem como alguns compostos bioativos que demonstram o valor e potencial das flores comestíveis.info:eu-repo/semantics/publishedVersio
Influence of solvent and high pressure treatment in the extraction of bioactive compounds in Gomphrena globosa L.
Gomphrena species are edible, commercial ornamental and medicinal plants commonly known as Globe Amaranth or Bachelor Button.1 The flowers of Gomphrena globosa L. have medicinal potential, once they are rich in bioactive compounds such as betacyanins, betalaines and flavonoids. Currently there is a very large and global interest in finding cheap and abundant sources of natural antioxidants. High pressure extraction has been recently applied to extract bioactive ingredients from plant materials, taking advantages of time saving, higher extraction yields, fewer impurities in the extraction solution, minimal heat and avoidance of thermal degradation on the activity and structure of bioactive components.2 The present study aimed to compare the influence of different extraction solvents (water, methanol, water:acetone (6:4; v:v)) and methods (heating under agitation (37 °C, 30 min) and high pressure (300 or 500 MPa) at different times (7.5 or 15 min)) on the content of flavonoids, hydrolysable tannins and antioxidant activity (Total Reducing Capacity, Scavenging of DPPH free radical and Reducing Power) in flower extracts. The water:acetone extracts obtained by heating under agitation had the highest values of flavonoids, hydrolysable tannins and Total Reducing Capacity, as well as the lowest EC50 values of DPPH free radical scavenging activity and Reducing Power, suggesting higher antioxidant activity than other solvents. When performing high pressure extraction it was found that different results were obtained with different time and pressure combinations, as well as solvents. The highest values of hydrolysable tannins and flavonoids were obtained with the binomial time/pressure of 15 min/300 MPa for all solvents, while the lowest EC50 value of DPPH was obtained at 15 min/500 MPa, for all solvents. The others parameters differed on the binomial time/pressure for the three solvents studied. For all parameters the values ranges were higher without high pressure than with high pressure application. Generally, for water and methanol extractions higher concentrations of flavonoids, hydrolysable tannins and Total Reducing Capacity were obtained after application of high pressure treatment in comparison to the traditional method, suggesting a higher extraction efficiency. On the other hand, with the water:acetone mixture, higher values of the former parameters were obtained without high pressure application.
In conclusion, the solvent and method used in the extraction directly influence the content of bioactive compounds of Bachelor Button. The results showed that high pressure extraction can be a promising method to extract more natural antioxidants. However, in future more studies must be performed on the compounds to be extracted after application of different time/pressure binomials to better understand their extractability.info:eu-repo/semantics/publishedVersio
Effect of solvent type and high pressure treatment on the extraction of Gomphrena globosa L. bioactive compounds
The present study aimed to compare the influence of different extraction solvents (water, methanol, water:acetone (6:4, v/v)), methods (heating (37 °C, 30 min) or high pressure (HP) (300 or 500 MPa) and extraction time (7.5 or 15 min)) on flavonoids, hydrolysable tannins and antioxidant activity (Total Reducing Capacity (TRC), DPPH Free Radical Scavenging Activity and Reducing Power) of Gomphrena globosa L. flower extracts. The water:acetone extracts obtained by heating had the highest values of flavonoids, hydrolysable tannins and antioxidant activity. When applying HP, variable results were obtained. Still, the
application of HP to water allowed to extract more hydrolysable tannins, as well as to obtain extracts with higher antioxidant activity than with heating, but no significant alterations were observed with methanol. In conclusion, both solvent and extraction method influence the content of bioactive compounds, being HP treatment a promising method to obtain enriched aqueous extracts in line with the principles of green-chemistry.The authors acknowledge the Portuguese Foundation for Science and Technology (FCT,
Portugal) for the financial support provided by the research grant SFRH/BD/95853/2013 and
FCT/MEC for the financial support to QOPNA research Unit (FCT UID/QUI/00062/2013)
and REQUIMTE (UID/QUI/50006/2013) through national funds and when applicable cofinanced
by the FEDER, within the PT2020 Partnership Agreement.info:eu-repo/semantics/publishedVersio
The unexplored potential of edible flowers lipids
Edible flowers have been historically linked to traditional world cuisine and culture. They are often used as ingredients in food and beverages for medicinal or pharmaceutical purposes. However, little attention has been paid to the quality of their lipids, and therefore to their potential for oil extraction and use in the food and food supplements industries. This review summarizes the current knowledge on the lipid composition of several edible flowers, including fat content, fatty acids, vitamin E, and carotenoids profiles. Edible flower lipids were found to be rich in linoleic (C18:2) and α-linolenic (C18:3) acids, which are essential fatty acids. Furthermore, most flowers are a good source of α-tocopherol and xanthophylls, such as lutein and zeaxanthin. This review provides valuable information on the lipid profile of some edible flowers in order to better characterize them and to increase their popularization among the food industry and consumers, boosting agriculture demand for these products.The authors acknowledge the Portuguese Foundation for Science and Technology (FCT, Portugal)
for the financial support provided by the research grant SFRH/BD/95853/2013 to Luana Fernandes and
FCT/MEC for the financial support to QOPNA research Unit (FCT UID/QUI/00062/2013) and LAQV research
Unit (UID/ QUI/50006/2013-POCI/01/0145/FEDER/007265) through national funds and co-financed by the
FEDER, within the PT2020 Partnership Agreement. Furthermore, the authors are grateful to FCT (Portugal)
and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013).info:eu-repo/semantics/publishedVersio
Borage, camellia, centaurea and pansies: Nutritional, fatty acids, free sugars, vitamin E, carotenoids and organic acids characterization
The present study aimed to evaluate the nutritional and bioactive potential of four edible flowers (borage,
centaurea, camellia, and pansies). Significant differences were observed among the four. Water was the main
constituent (> 76%, fresh weight - fw). Linoleic and palmitic acids were the major fatty acids found in borage
and red and yellow pansies, while in camellia it was the arachidic acid. In white pansies, behenic and arachidic
acids were predominant. Concerning vitamin E, α-tocopherol was the major vitamer. Carotenoids values varied
between 5.8 and 181.4 mg β-carotene/100 g dry weight (dw) in centaurea and borage, respectively, being
particularly rich in lutein. Malic acid was the major organic acid, except in centaurea, where succinic acid was
predominant. Fructose, glucose and sucrose were detected in all flowers. These results can contribute to the
knowledge of these edible flowers and consequently increase their popularity among consumers and in the food
industry.The authors acknowledge the Portuguese Foundation for Science
and Technology (FCT, Portugal) for the financial support provided by
the research grant SFRH/BD/95853/2013 to Luana Fernandes, and
FCT/MCT for the financial support to QOPNA research Unit (FCT UID/
QUI/00062/2019) and LAQV research Unit (UID/QUI/50006/2019)
through national funds and co-financed by the FEDER, within the
PT2020 Partnership Agreement. Furthermore, the authors are grateful
to the Foundation for Science and Technology (FCT, Portugal) and
FEDER under Programme PT2020 for financial support to CIMO (UID/
AGR/00690/2019).info:eu-repo/semantics/publishedVersio
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