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31.
Antigenotoxic effect of grape seed procyanidin extract in Fao cells submitted to oxidative stress 总被引:4,自引:0,他引:4
Llópiz N Puiggròs F Céspedes E Arola L Ardévol A Bladé C Salvadó MJ 《Journal of agricultural and food chemistry》2004,52(5):1083-1087
The protective effects of grape seed procyanidin extract on the repair of H(2)O(2)-induced DNA lesions were tested using Fao cells. Cells were exposed to 600 microM H(2)O(2) for 3 or 21 h. A procyanidin extract from grape seed (PE) was incubated or preincubated (1 h) during the exposure to H(2)O(2). The ability of procyanidins to protect against the genotoxicity of H(2)O(2) was compared with those of the monomeric flavanols (+)-catechin and (-)-epicatechin and the flavonol quercetin. After treatment, DNA damage was monitored using alkaline single-cell gel electrophoresis (the comet assay) (Aherne, S. A.; O'Brien, N. M. Nutr. Cancer 1999, 34, 160-166). At the end of the experiment, PE significantly decreased the damage caused by H(2)O(2). The results also showed that quercetin was the most effective of the flavonoids tested, which is consistent with its powerful antioxidant character. The results indicate that procyanidins are more effective than the corresponding individual monomers, catechin and epicatechin, at preventing DNA lesions in hepatocytes and that this protection is higher after preincubation than after co-incubation. 相似文献
32.
Antioxidant activity and phenolic composition of wild, edible, and medicinal fennel from different Mediterranean countries 总被引:1,自引:0,他引:1
Faudale M Viladomat F Bastida J Poli F Codina C 《Journal of agricultural and food chemistry》2008,56(6):1912-1920
Fennel (Foeniculum vulgare Mill.) is a typical aromatic plant of the Mediterranean area, long used as a medicinal and spice herb. Fennel is also well-known for its essential oil, which has been extensively studied for many years owing to its commercial importance. In this work, the antioxidant activity and the total phenolic and flavonoid contents, as well as the quantitative determination of individual flavonoids and phenolic acids of wild, edible, and medicinal fennel from different Mediterranean countries, have been determined. The antioxidant activity was measured as the free radical (DPPH), hydroxyl radical, and superoxide anion scavenging activities. Wild fennel was found to exhibit a radical scavenging activity, as well as a total phenolic and total flavonoid content, higher than those of both medicinal and edible fennels. 相似文献
33.
Marine reserves are increasingly advocated not only as conservation but also as fisheries management tools to safeguard the decline of coastal fishing resources. Still, conclusive evidence of their functioning is lacking, amongst others due to the influence of spatio-temporal variations in fish populations and habitat heterogeneity which could hamper a sound data interpretation. We conducted a spatial analysis of the benefits of the Medes Island Marine Reserve by combining geostatistical and Geographic Information System (GIS) tools. Concurrently, we analysed effects of trends reflecting habitat heterogeneity and spatial structuring of data on spatial predictions of fish catch per unit effort (CPUE) and length. Predicted spatial patterns showed the complexity and simultaneous action of trend factors leading to mostly non-linear gradients in CPUE and length data. CPUE of total fish and CPUE and length of common pandora (Pagellus erythrinus) increased close to the Integral Reserve due to direct and indirect reserve effects. CPUE and length of striped red mullet (Mullus surmuletus) slightly increased also near the Integral Reserve, but distinct reserve effects could not be identified due to the strong influence of artificial reefs. We conclude that the spatial dimension of the Buffer Zone, where artisanal fisheries are allowed, permits in general protection only for target species, favouring a habitat with no discontinuities from the reserve outwards. Our spatial approach to assess reserve benefits provides major insights into complex systems like coastal marine reserves in the northwestern Mediterranean. In addition, it contributes to a crucial aspect of marine conservation, viz. the decision on the spatial dimension of protected areas. 相似文献
34.
This paper aims to enrich the analysis on the significance of the individual firm resources in a cluster and the effects of diverse cluster relationships, including local and non‐local ones, on firms' innovation capacity. On questioning the commonly accepted direct and positive impact, we explore the joint and non‐linear effects of internal resources and inter‐organisational relationships on innovation. Data from 251 footwear manufacturers located in the Spanish Vinalopó cluster were used to explore the proposed causal relationships. According to findings, the impact of each factor on product innovation is not homogeneous. Internal innovation efforts and cooperation with local suppliers positively affect the creation of new products, while collaboration with local customers and extra‐cluster linkages presents an inverted U‐shaped relationship with product innovation. Finally, a number of implications may be drawn for policy makers, practitioners, and future research. 相似文献
35.
Francesc Piferrer Michael Redding Wilfrid DuBois Gloria Callard 《Fish physiology and biochemistry》1993,11(1-6):293-298
Spermatogenesis is a unique developmental sequence involving multiple cell to cell interactions and several categories of regulatory molecules. In contrast to conventional mammalian models in which testicular organization is highly complex, the testis of the dogfish shark Squalus acanthias is technically advantageous for elucidating stage-dependent structural and functional charactericsics and for in vitro regulatory studies. Using incorporation of [3H]thymidine into acid-insoluble molecules as a measure of DNA synthesis by spermatocysts (germ cell/Sertoli cell units) of premeiotic stages, we obtained evidence of a growth inhibitory bioactivity (chalone) within the testis. This activity is differentially distributed (postmeiotic > meiotic > premeiotic), suggesting that more advanced developmental stages, which are upstream in the vascular pathway within the testis, may control the size of the proliferating spermatocyst population and, hence, the advance of less mature stages. These data provide direct evidence for humoral communication between stages of spermatogenesis. 相似文献
36.
Characteristic arable weed species of dryland cereal fields have undergone significant declines, due to agricultural intensification, to the point that some of them are considered rare. Crop edges host higher abundances of arable weed species, therefore they may act as a refuge for the conservation of these rare arable species. Using mesocosms, we experimentally tested how conditions at field edges (i.e. lower sowing densities and less intensive fertiliser applications) operate on the growth (biomass and height) and reproduction (reproductive biomass and flower onset) of six rare arable species. We found the rare arable species achieved lower biomass when growing with wheat compared with growing alone, and biomass of most of species was lower under high wheat sowing density than under low sowing density. In contrast, fertiliser application affected only two of the six arable species tested, especially when they were growing alone. Although the time to flowering was not affected by the conditions tested, reproductive biomass showed the same trends as overall biomass. These results indicate that conservation of rare arable species must primarily consider reductions in crop competition to increase their biomass and reproductive ability. 相似文献
37.
Felipe Siverio Emilio A. Carbonell Francesc García María M. López 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(6):519-526
The fatty acid methyl ester (FAME) profiles of eighty strains ofPseudomonas corrugata from different geographic origins have been studied. Gas chromatographic profiles were obtained. The use of hexane/methyl-tert butyl ether (MTBE) (11) for the extractions improves the yield of hydroxy-FAMEs used to identifyP. corrugata as compared to hexane alone. The analysis of the extracts with hexane/MTBE showed that many strains do not have the characteristic FAMEs ofP. corrugata (3-hydroxydodecenoic acid, 3-hydroxytetradecanoic acid, 3-hydroxyhexadecanoic acid and two unknown additional fatty acids). These differences among strains seemed to be related to bacterial dissociation, associated with changes in morphological aspect of the colonies due to subculture. The comparison of profiles of wrinkled and smooth colonies isolated from ten strains confirmed the differences among those in specific FAMEs. Therefore, the FAME profiles are a useful tool for the identification ofP. corrugata when the bacteria have not been subculturedin vitro for a long time. Multivariate analyses of data showed that four clusters can be observed supporting the heterogeneity of the strains ofP. corrugata.Abbreviations FAME
fatty acid methyl ester
- MTBE
methyl tert-butyl ether 相似文献
38.
Bou R Grimpa S Baucells MD Codony R Guardiola F 《Journal of agricultural and food chemistry》2006,54(14):5020-5026
The effects of dietary alpha-tocopheryl acetate (alpha-TA) doses (75, 150, and 225 mg/kg) and the duration of this supplementation (0, 10, 21, 32, and 43 days prior to slaughter) on fatty acid composition, alpha-tocopherol content, and oxidative status were studied either in raw or in cooked dark chicken meat with its skin. With regard to fatty acid composition, raw meat was affected by both dietary factors. Various polyunsaturated fatty acids decreased as a result of higher alpha-TA doses, whereas these fatty acids increased with longer supplementation periods. Cooked meat showed similar trends for the duration of alpha-TA supplementation. On the other hand, alpha-tocopherol content in raw and cooked meat increased as a result of the dose and duration of alpha-TA supplementation. Formation of lipid hydroperoxides and thiobarbituric acid values of these meats were also influenced by these two dietary factors, and the dietary combination of 150 mg/kg of alpha-TA during the last 32 days was optimal in terms of supplementation costs and meat oxidative stability. 相似文献
39.
This study evaluates the effects of replacing beef tallow added to rabbit feeds (3% w/w) by different doses (0%, 1.5% and 3% w/w) of n-6- or n-3-rich vegetable fat sources (sunflower and linseed oil, respectively) and alpha-tocopheryl acetate supplementation (0 and 100 mg/kg) on the fatty acid composition, alpha-tocopherol content, and oxidation levels [assessed by analyzing thiobarbituric acid (TBA) and lipid hydroperoxide values] in rabbit meat. We also measured these parameters after cooking and refrigerated storage of cooked rabbit meat. Both dietary alpha-tocopheryl acetate supplementation and the dose and source of fat added to feeds influenced meat fatty acid composition, modifying the n-6/n-3 ratio, which was more nutritionally favorable when linseed oil was used. Furthermore, the addition of linseed oil and the supplementation with alpha-tocopheryl acetate enhanced long-chain PUFA biosynthesis. However, the addition of 3% linseed oil increased meat oxidation, and although it was reduced by dietary supplementation with alpha-tocopheryl acetate in raw meat, this reduction was not as effective after cooking. Therefore, dietary supplementation with 1.5% linseed oil plus 1.5% beef tallow and with alpha-tocopheryl acetate would be recommended to improve the nutritional quality of rabbit meat. 相似文献
40.
María Rosa Yagüe Francesc Domingo‐Oliv ngela Dolores Bosch‐Serra Rosa Maria Poch Jaume Boixadera 《Land Degradation \u0026amp; Development》2016,27(7):1753-1762
In the European Union, the maintenance of soil quality is a key point in agricultural policy. The effect of additions of dairy cattle (Bos taurus) manure (DCM) during a period of 11 years were evaluated in a soil under irrigated maize (Zea mays L.) monoculture. DCM was applied at sowing, at wet‐weight rates of 30 or 60 Mg ha−1yr−1 (30DCM or 60DCM). These were compared with a mineral‐N treatment (300 kg N ha−1, MNF), applied at six to eight emerged leaves and with a control (no N, no manure). Treatments were distributed in a randomized block design. Factors analysed were stability against wetting stress disaggregation, porosity, soil organic carbon (SOC) fractions and earthworm abundance, studied eight months after the last manure application. The application rate of 30DCM increased aggregate stability and the light SOC fraction, but not the pore volume, nor the earthworm abundance, compared with MNF. The DCM rates did not result in unbalanced agronomic advantages versus MNF, as high yields (12–16 Mg ha−1 yr−1) were obtained. In Mediterranean environments, the use of DCM should be encouraged mainly because of its contribution to the light SOC fraction which protects dry macro‐aggregates from implosion (slaking) during the wetting process. Thus, in intensive agricultural systems, it protects soil from physical degradation. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献