Página 1 dos resultados de 6 itens digitais encontrados em 0.000 segundos

Antioxidant activity, ascorbic acid, phenolic compounds and sugars of wild and commercial Tuberaria lignosa samples: effects of drying and oral preparation methods.

Pinela, José; Barros, Lillian; Dueñas, Montserrat; Carvalho, Ana Maria; Santos-Buelga, Celestino; Ferreira, Isabel C.F.R.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
17.77%
The antioxidant activity and phytochemical composition (ascorbic acid, free sugars and phenolic compounds) of decoctions and infusions of wild and commercial samples of Tuberaria lignosa (Sweet) Samp. (Fam. Cistaceae) aerial parts were evaluated and compared. Among wild samples, the effects of the drying method (freeze or shade-drying) on those parameters were studied. Infusion of the freeze-dried wild sample gave the highest levels of sugars, while infusion of shade-dried wild sample and decoction of the freeze-dried sample presented higher ascorbic acid and phenolic compounds content (including ellagitanins and flavonoids) than the other samples. The last two samples also revealed higher antioxidant activity and, in some cases, even higher than trolox. Decoctions gave lower amounts of disaccharides than infusions, which seemed to be hydrolyzed increasing the content in monosaccharides in the first samples. Commercial samples showed the lowest content in phenolic compounds, mainly in ellagitanins and flavonoids, as also the lowest antioxidant activity. This work gives scientific evidences to the traditional medicinal uses of wild Tuberaria lignosa, highlighting the interest of its decoctions and infusions as bioactive compounds source and functional beverages.

Tuberaria lignosa preparations: influence of drying methods and oral dosage forms on antioxidant properties and phytochemical composition

Pinela, José; Barros, Lillian; Dueñas, Montserrat; Carvalho, Ana Maria; Santos-Buelga, Celestino; Ferreira, Isabel C.F.R.
Fonte: Instituto Politécnico de Bragança Publicador: Instituto Politécnico de Bragança
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
17.01%
Many herbal beverages used in folk medicine have pharmacological properties connected with the presence of antioxidants such as phenolic compounds. Tuberaria lignosa (Sweet) Samp. (Cistaceae) is one of the most popular medicinal plants in several regions of the Iberian Peninsula used to prepare herbal infusions or decoctions. In the present work, the effects of drying (freeze or shade-drying) and preparation methods (water infusion or decoction) on the antioxidant activity and phytochemical composition of wild and commercial samples of Tuberaria lignosa were evaluated. Infusion of the freeze-dried wild sample led to the highest levels of sugars, while infusion of shade-dried wild sample and decoction of the freeze-dried sample retained the highest ascorbic acid and phenolic compounds levels These two samples revealed the highest antioxidant activity, even higher, in some cases, than trolox Decoctions had lower amounts of disaccharides than infusions, which seemed to be hydrolyzed increasing the content in monosaccharides. Commercial samples showed much lower contents in phenolic compounds, mainly in ellagitanins and flavonoids, as also the lowest antioxidant activity. Data give scientific evidence to folk medicinal uses of Tuberaria lignosa. highlighting the interest of its decoctions and infusions as sources of bioactive compounds (e.g. phenolic compounds and ascorbic acid).

Characterization of phenolic compounds and antioxidant potential of infusion and decoction of the wild medicinal plant Tuberaria lignosa (Sweet) Samp.

Barros, Lillian; Pinela, José; Dueñas, Montserrat; Carvalho, Ana Maria; Santos-Buelga, Celestino; Ferreira, Isabel C.F.R.
Fonte: Instituto Politécnico de Bragança Publicador: Instituto Politécnico de Bragança
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
17.01%
Many herbal beverages, frequently used in folk medicine, have pharmacological properties connected with the presence of antioxidants such as phenolic compounds. Tuberaria lignosa (Sweet) Samp. (Fam. Cistaceae) is one of the most popular medicinal plants in several regions of the Iberian Peninsula used to prepare herbal infusions or decoctions [1 ].1n the present work, the antioxidant activity of wild T. lignosa infusion and decoction was evaluated by four different methodologies (free radical scavenging activity, reducing power and lipid peroxidation inhibition) and the phenolic composition was determined by HPLC-DAD-ESI/MS. Ellagitanins and flavonoids were the main phenolic compounds found, being punicalagin and punicalagin gallate the most abundant compounds ( - 123 and 98 mg/g of infusion and decoction, respectively). The infusion and decoction presented very similar results in the amounts of phenolic compounds, but the antioxidant potential was slightly higher in the decoction preparation. Both samples revealed high antioxidant activity (EC50 values lower than 57.3 llg/ml), even higher, in some cases, than the standard trolox. This work gives scientific evidences to the traditional medicinal uses of wild Tuberaria lignosa...

Effect of ellagitannins, ellagic acid and volatile compounds from oak wood on the (+)-catechin, procyanidin B1 and malvidin-3-glucoside content in model wines

Jordão, A.M.; Ricardo-da-Silva, J.M.; Laureano, O.; Mullen, W.; Crozier, A.
Fonte: ASVO Publicador: ASVO
Tipo: Artigo de Revista Científica
Publicado em //2008 ENG
Relevância na Pesquisa
17.01%
Background and Aims: During ageing in oak barrels, wine undergoes changes because of the release of polyphenols and other molecules from wood. The aim of this study was to evaluate the influence of some oak wood-derived volatile compounds, ellagic acid and oak wood extracts on the levels of (+)-catechin, procyanidin B1 and malvidin-3-glucoside. Methods and Results: Phenolics and the oak wood derived volatile compounds studied were quantified by HPLC and by GC, respectively. Additionally, the new compounds formed in the solutions were characterised by their spectral properties. Ellagic acid and/or oak wood extracts slowed the decline in the levels of (+)-catechin and procyanidin B1. In contrast, the decrease in malvidin-3-glucoside was more pronounced in the presence of ellagic acid and oak wood chip extracts. Furfural slowed (+)-catechin degradation, while breakdown of malvidin-3-glucoside was slightly more pronounced in the presence of guaiacol, furfural, vanillin and eugenol. (+)-Catechin, procyanidin B1 and malvidin-3-glucoside did not significantly affect the rate of the degradation of ellagitannins during the storage time studied. Finally, new HPLC peaks were detected in the solutions containing (+)-catechin and ellagic acid...

Consumption of strawberries on a daily basis increases the non-urate 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging activity of fasting plasma in healthy subjects

Prymont-Przyminska, Anna; Zwolinska, Anna; Sarniak, Agata; Wlodarczyk, Anna; Krol, Maciej; Nowak, Michal; de Graft-Johnson, Jeffrey; Padula, Gianluca; Bialasiewicz, Piotr; Markowski, Jaroslaw; Rutkowski, Krzysztof P.; Nowak, Dariusz
Fonte: the Society for Free Radical Research Japan Publicador: the Society for Free Radical Research Japan
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
17.01%
Strawberries contain anthocyanins and ellagitanins which have antioxidant properties. We determined whether the consumption of strawberries increase the plasma antioxidant activity measured as the ability to decompose 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) in healthy subjects. The study involved 10 volunteers (age 41 ± 6 years, body weight 74.4 ± 12.7 kg) that consumed 500 g of strawberries daily for 9 days and 7 matched controls. Fasting plasma and spot morning urine samples were collected at baseline, during fruit consumption and after a 6 day wash-out period. DPPH decomposition was measured in both deproteinized native plasma specimens and pretreated with uricase (non-urate plasma). Twelve phenolics were determined with HPLC. Strawberries had no effect on the antioxidant activity of native plasma and circulating phenolics. Non-urate plasma DPPH decomposition increased from 5.7 ± 0.6% to 6.6 ± 0.6%, 6.5 ± 1.0% and 6.3 ± 1.4% after 3, 6 and 9 days of supplementation, respectively. The wash-out period reversed this activity back to 5.7 ± 0.8% (p<0.01). Control subjects did not reveal any changes of plasma antioxidant activity. Significant increase in urinary urolithin A and 4-hydroxyhippuric (by 8.7- and 5.9-times after 6 days of supplementation with fruits) was noted. Strawberry consumption can increase the non-urate plasma antioxidant activity which...

La granada. Alimento rico en polifenoles antioxidantes y bajo en calorías

García-Viguera, Cristina; Pérez-Vicente, Antonio
Fonte: Arán Ediciones Publicador: Arán Ediciones
Tipo: Artículo Formato: 259768 bytes; application/pdf
SPA
Relevância na Pesquisa
17.01%
8 páginas, 3 figuras, 1 tabla.; [ES] La granada es un alimento, bastante desconocido para el consumidor, pero que presenta una elevada concentración de polifenoles con demostrada actividad antioxidante y unas buenas características nutricionales, Siendo además un fruto atractivo por su bajo aporte calórico. En el presente trabajo se realizará un resumen de sus características nutricionales y los efectos beneficiosos que aporta su consumo para la salud humana. No obstante, nos centraremos más en el estudio de los polifenoles, metabolitos secundarios que le confieren sus propiedades organolépticas y capacidad antioxidante, así como en las posibles transformaciones que sufren los mismos durante la digestión gastro-intestinal, con el fin de determinar el grado de alteración que sufre su capacidad captadora de radicales libres una vez ingerido el fruto. Por último, se expondrán una serie de alternativas al consumo en fresco de la granada, ya que la elaboración de alimentos procesados puede ser una solución efectiva para incrementar el consumo de este alimento.; [EN] Pomegranate is a quite unknown food, rich in polyphenols which confer high antioxidant activity. It is also a low calorie fruit with very good nutritive characteristics...