Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
J Agric Food Chem ; 55(22): 8972-9, 2007 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-17907774

RESUMEN

The effect of fermentation on the antioxidant compounds [vitamins C and E, total phenolic compounds (TPC), and reduced glutathione (GSH)], and antioxidant capacity [superoxide anion scavenging activity (SOD-like activity), peroxyl radical-trapping capacity (PRTC), inhibition of phosphatidylcholine (PC) peroxidation, and Trolox equivalent antioxidant capacity (TEAC)] of soybean (Glycine max cv. Merit) was studied. Fermentation was carried out in solid state in cracked seeds inoculated with Aspergillus oryzae, Rhizopus oryzae, Bacillus subtilis, and Lactobacillus plantarum and in liquid state either in cracked seeds or milled soybean flours fermented naturally by only the microorganisms present in the seeds or by inoculation with L. plantarum. Vitamin C was not detected in the studied samples. Fermentation caused a decrease in vitamin E activity, except when cracked seed was fermented with A. oryzae, R. oryzae, or B. subtilis that increased 31, 30, and 89%, respectively. Fermentation produced an increase in TPC content and did not affect or reduce the GSH content. Fermentation decreased SOD-like activity drastically, while PRTC increased except when it was carried out naturally in cracked seed. TEAC values rose sharply when soybeans were fermented with B. subtilis. Processed soybean extracts inhibited PC peroxidation in comparison with the control assay. On the basis of the results obtained, the relative contributions of vitamin E, TPC, and GSH to antioxidant capacity were calculated and results showed a very high TPC contribution and a low contribution of GSH and vitamin E activity. Optimum results for functional soybean flours were achieved when fermentation was carried out with B. subtilis inoculum.


Asunto(s)
Fermentación , Manipulación de Alimentos/métodos , Glycine max/química , Semillas/química , Alimentos de Soja/análisis , Antioxidantes/análisis , Ácido Ascórbico/análisis , Glutatión/análisis , Vitamina E/análisis
2.
Food Chem ; 141(3): 2864-72, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23871035

RESUMEN

The carotenoid profile of sixty potato cultivars (commercial, bred, old and native cultivars) has been characterised in order to provide information to be used in selective breeding programs directed to improve the nutritional value of this important staple food. Cultivars were segregated into three groups according to the major pigment in the carotenoid profile: violaxanthin (37 cultivars; especially those with higher carotenoid content), lutein (16 cultivars), and neoxanthin (7 cultivars). Other minor carotenoids were antheraxanthin, ß-cryptoxanthin and ß-carotene, while zeaxanthin was absent in all sample. The total carotenoid content ranged from 50.0 to 1552.0 µg/100 g dry wt, with an average value of about 435.3 µg/100 g dry wt. Sipancachi, Poluya and Chaucha native cultivars showed the highest carotenoid content (1020.0, 1478.2 and 1551.2 µg/100 g dry wt, respectively). Xanthophyll esters were present in most cultivars, mainly as diesterified forms, being observed a direct correlation between the carotenoid content and the esterified fraction, suggesting that the esterification process facilitates the accumulation of these lipophilic compounds within the plastids. Therefore, the presence of xanthophyll esters should be a phenotypic character to be included in the breeding studies, and more efforts should be dedicated to the understanding of the biochemical process leading to this structural modification of carotenoids in plants.


Asunto(s)
Carotenoides/metabolismo , Tubérculos de la Planta/metabolismo , Solanum tuberosum/metabolismo , Xantófilas/metabolismo , Carotenoides/análisis , Esterificación , Tubérculos de la Planta/química , Solanum tuberosum/química , Solanum tuberosum/clasificación , Xantófilas/química
3.
J Agric Food Chem ; 58(17): 9341-52, 2010 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-20707366

RESUMEN

Phenolic acid content and composition have been determined in 26 wheat genotypes grown in Hungary over three consecutive years and at three additional locations (France, United Kingdom, and Poland) during the third year. Fractions comprising free, soluble conjugated, and bound phenolic acids were analyzed using HPLC with measurements being made for individual phenolic acids in each fraction. Statistically significant differences in phenolic acid content occurred across the different growing locations with the average total phenolic acid content being highest in the genotypes grown in Hungary. The growth year in Hungary also had a large impact, especially on the free and conjugated phenolic acid contents. Certain genotypes were more resistant to environmental impacts than others. Of the genotypes with high levels of total phenolic acids, Lynx, Riband, Tommi, and Cadenza were most stable with respect to their total contents, whereas Valoris, Herzog, and Malacca, also high in phenolic acid content, were least stable. Of the three fractions analyzed, the free and conjugated phenolic acids were most variable and were also susceptible to the effect of environment, whereas bound phenolic acids, which comprised the greatest proportion of the total phenolic acids, were the most stable.


Asunto(s)
Ambiente , Hidroxibenzoatos/análisis , Triticum/química , Cromatografía Líquida de Alta Presión , Genotipo , Triticum/genética
4.
J Agric Food Chem ; 58(17): 9291-8, 2010 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-20438061

RESUMEN

Analysis of the contents of bioactive components (tocols, sterols, alkylresorcinols, folates, phenolic acids, and fiber components) in 26 wheat cultivars grown in six site x year combinations showed that the extent of variation due to variety and environment differed significantly between components. The total contents of tocols, sterols, and arabinoxylan fiber were highly heritable and hence an appropriate target for plant breeding. However, significant correlations between the contents of bioactive components and environmental factors (precipitation and temperature) during grain development also occurred, with even highly heritable components differing in amount between grain samples grown in different years on different sites.


Asunto(s)
Fibras de la Dieta/análisis , Variación Genética , Triticum/clasificación , Genotipo , Triticum/química , Triticum/genética
5.
J Agric Food Chem ; 58(17): 9372-83, 2010 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-20438063

RESUMEN

The effects of genotype and environment on the content of bioactive components in rye were determined with four varieties being grown on one site for three years and on three additional sites in the third year and a fourth variety being included in all trials except year 1. Clear differences were observed in the extent to which the contents of dietary fiber components (arabinoxylan, beta-glucan, total dietary fiber) and phytochemicals (folates, alkylresorcinols, sterols, tocols, phenolic acids) varied between varieties and between the same varieties grown in different sites (United Kingdom, France, Hungary, Poland) and years (2005-2007 in Hungary), with sterols being the most stable and phenolic acids the least. However, no single variety could be selected as having the highest overall level of bioactive components or as being more stable in comparison across environments.


Asunto(s)
Fibras de la Dieta/análisis , Ambiente , Secale/química , Genotipo , Secale/genética
6.
Nahrung ; 47(5): 291-9, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14609082

RESUMEN

In this study four cultivars of lentil originating from Spain were examined: cv Paula, cv Agueda, cv Almar and cv Alcor. Since consumption of these seeds after heat treatment and as sprouts has been popularised, the impact of cooking (up to 30 min) and germination process (in dark, at 25 degrees C, for up to 4 days) on peroxyl radical-trapping capacity (PRTC) and Trolox-equivalent antioxidant capacity (TEAC) of the processed seeds was addressed. Also, changes in the content of low-molecular-weight antioxidants (LMWA) and soluble proteins in the course of cooking and germination were studied. The analyzed LMWAwere: total phenolics, tocopherols (alpha-T, beta-T, gamma-T, delta-T), reduced glutathione, and L-ascorbic acid. On the basis of the results obtained, the contribution of LMWA and soluble proteins to the PRTC and TEAC of raw, cooked, and germinated lentil seeds was calculated by multiple mean values for the content of investigated compounds and their relative potential with respect to Trolox. The results showed avery high molar percentage contribution of phenolic compounds and low contribution of tocopherols, glutathione, soluble proteins, and ascorbate (only in germinated seeds) to the total TEAC and total PRTC calculated as a sum of data provided for phosphate-buffered and 80% methanolic extracts of raw and processed lentil seeds.


Asunto(s)
Antioxidantes/análisis , Germinación , Lens (Planta)/química , Proteínas de Plantas/análisis , Semillas/química , Antioxidantes/química , Ácido Ascórbico/análisis , Culinaria , Manipulación de Alimentos/métodos , Radicales Libres , Glutatión/análisis , Calor , Humanos , Peso Molecular , Valor Nutritivo , Oxidación-Reducción , Fenoles/análisis , Solubilidad , Tocoferoles/análisis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA