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991.
Sánchez-Patán F Cueva C Monagas M Walton GE Gibson GR Quintanilla-López JE Lebrón-Aguilar R Martín-Álvarez PJ Moreno-Arribas MV Bartolomé B 《Journal of agricultural and food chemistry》2012,60(9):2136-2147
An in vitro batch culture fermentation experiment was conducted with fecal inocula from three healthy volunteers in the presence and absence of a red wine extract. Changes in main bacterial groups were determined by FISH during a 48 h fermentation period. The catabolism of main flavonoids (i.e., flavan-3-ols and anthocyanins) and the formation of a wide a range of phenolic microbial metabolites were determined by a targeted UPLC-PAD-ESI-TQ MS method. Statistical analysis revealed that catechol/pyrocatechol, as well as 4-hydroxy-5-(phenyl)-valeric, 3- and 4-hydroxyphenylacetic, phenylacetic, phenylpropionic, and benzoic acids, showed the greatest increases in concentration during fermentation, whereas 5-(3'-hydroxyphenyl)-γ-valerolactone, its open form 4-hydroxy-5-(3'-hydroxyphenyl)-valeric acid, and 3,4-dihydroxyphenylacetic acid represented the largest interindividual variations in the catabolism of red wine polyphenols. Despite these changes, microbial catabolism did not produce significant changes in the main bacterial groups detected, although a slight inhibition of the Clostridium histolyticum group was observed. 相似文献
992.
Llorach R Garcia-Aloy M Tulipani S Vazquez-Fresno R Andres-Lacueva C 《Journal of agricultural and food chemistry》2012,60(36):8797-8808
Correctly assessing the metabolic status of subjects after consumption of specific diets is an important challenge for modern nutrition. Recently, metabolomics has been proposed as a powerful tool for exploring the complex relationship between nutrition and health. Nutritional metabolomics, through investigating the role that dietary components play in the maintenance of health and development of risk disease, aims to identify new biomarkers that allow the intake of these compounds to be monitored and related to their expected biological effects. This review offers an overview of the application of nutrimetabolomic strategies in the discovery of new biomarkers in human nutritional research, suggesting three main categories: (1) assessment of nutritional and dietary interventions; (2) diet exposure and food consumption monitoring; and (3) health phenotype and metabolic impact of diet. For this purpose, several examples of these applications will be used to provide evidence and to discuss the advantages and drawbacks of these nutrimetabolomic strategies. 相似文献
993.
Lde S Oliveira CF Moura ES De Brito RV Mamede MR De Miranda 《Journal of agricultural and food chemistry》2012,60(32):7957-7964
The present research work describes the major changes in the antioxidant properties during development of acerola from five different clones. Ripening improved fruit physicochemical quality parameters; however, total vitamin C and total soluble phenols (TSP) contents declined during development, which resulted in a lower total antioxidant activity (TAA). Despite the decline in TSP, at ripening, the anthocyanin and yellow flavonoid content increased and was mainly constituted of cyanidin 3-rhamnoside and quercetin 3-rhamnoside, respectively. The activities of oxygen-scavenging enzymes also decreased with ripening; furthermore, the reduction in vitamin C was inversely correlated to membrane lipid peroxidation, indicating that acerola ripening is characterized by a progressive oxidative stress. Among the studied clones, II47/1, BRS 237, and BRS 236 presented outstanding results for vitamin C, phenols, and antioxidant enzyme activity. If antioxidants were to be used in the food supplement industry, immature green would be the most suitable harvest stage; for the consumer's market, fruit should be eaten ripe. 相似文献
994.
Alma Rosa Netzahuatl-Muñoz Flor de María Guillén-Jiménez Benjamín Chávez-Gómez Thelma Lilia Villegas-Garrido Eliseo Cristiani-Urbina 《Water, air, and soil pollution》2012,223(2):625-641
Solution pH is among the most important parameters that influence heavy metal biosorption. This work presents a kinetic study
of the effects of pH on chromium biosorption onto Cupressus lusitanica Mill bark from aqueous Cr(VI) or Cr(III) solutions and proposes a mechanism of adsorption. At all assayed contact times,
the optimum pH for chromium biosorption from the Cr(III) solution was 5.0; in contrast, optimum pH for chromium biosorption
from the Cr(VI) solution varied depending on contact time. The kinetic models that satisfactorily described the chromium biosorption
processes from the Cr(III) and Cr(VI) solutions were the Elovich and pseudo second-order models, respectively. Diffuse reflectance
infrared Fourier transform spectroscopy studies suggest that phenolic compounds present on C. lusitanica Mill bark play an important role in chromium biosorption from the Cr(III) solution. On the other hand, chromium biosorption
from the Cr(VI) solution involved carboxyl groups produced on the bark by redox reactions between oxygen-containing groups
and Cr(VI), and these were in turn responsible for the biosorption of Cr(III) produced by Cr(VI) reduction. 相似文献
995.
Rosa María Carbonell-Bojollo Miguel Angel Repullo-Ruibérriz de Torres Antonio Rodríguez-Lizana Rafaela Ordó?ez-Fernández 《Water, air, and soil pollution》2012,223(6):3425-3435
Many of the environmental problems related to agriculture will still be serious over the next 30?years. However, the seriousness of some of those problems may increase more slowly than in the past or even diminish in other cases (FAO 2002). Agriculture plays two different roles in climate change; on one hand, it suffers from the impact of climate change, on the other hand, it is responsible for 14?% of total greenhouse gases (MMA 2008). Nevertheless, agriculture is also part of the solution, as it is capable of mitigating a significant amount of global emissions, according to the FAO (2001). This paper aims to study the influence of edapho-climate conditions on soil CO2 emissions into the atmosphere. In order to do so, we conducted three field trials in different areas in southern Spain, which have different soil textures and different climate conditions. The results show how interaction between the temperature and rainfall recorded has a greater influence on emissions than each of the factors separately. However, at the same time, the texture of the soil at each of the locations was also found to be the most dominant variable in the gas emission process. 相似文献
996.
A Geostatistical Approach to Assess Concentration and Spatial Distribution of Heavy Metals in Urban Soils 总被引:2,自引:0,他引:2
Ilaria Guagliardi Domenico Cicchella Rosanna De Rosa 《Water, air, and soil pollution》2012,223(9):5983-5998
Characterization of spatial variation of heavy metals in urban soils is essential to identify pollution sources and potential risks to humans and the environment. While heavy metals concentration in soils depends also on the nature of bedrock and on abiotic and biotic factors, it can be argued that nowadays, due to increasing human activities, it is determined mainly by anthropogenic sources. We determined concentrations and spatial distribution of heavy metals, with particular focus on those potentially toxic (As, Cr, Pb, V, and Zn), in urban and peri-urban soils of Cosenza-Rende (southern Italy). One hundred forty-nine samples of topsoil (0?C10?cm) were collected and analyzed for 36 elements by X-ray fluorescence spectrometry and inductively coupled plasma mass spectrometry (ICP-MS). In addition, 18 samples of rocks were collected on outcrops of whole area and analyzed by ICP-ES and ICP-MS. Geostatistical methods were used to map the concentrations of major oxides and several minor elements. Heavy metals in the analyzed samples showed a wide range of concentrations, primarily controlled by the geochemical composition of bedrock, with the notable exceptions of Cu, Pb, and Zn, whose concentrations are heavily affected by land use and anthropogenic pollution in urban areas. Geochemical analysis and spatial distribution showed that high concentrations of potentially toxic elements are found in soils near major roads, indicating that anthropogenic factors determine the anomalies in these areas. 相似文献
997.
998.
999.
Rosa Honorato de Oliveira Camilla Rosindo Dias Milanez Marina Aparecida Moraes-Dallaqua Ciro Antonio Rosolem 《Journal of plant nutrition》2013,36(11):2035-2048
ABSTRACT The effect of boron (B) on cotton growth and fruit shedding may be due not only to physiological or biochemical effects, but also to vascular tissue malformation. This experiment investigated petiole and floral peduncle anatomical alterations and growth of cotton supplied with deficient and sufficient B in nutrient solution. Cotton (Gossypium hirsutum cv. ‘Delta Opal’) plants were grown in solutions containing 0, 1.5, 3.0, 4.5, and 6.0 μmol L?1 of B from 22 to 36 d after plant emergence (DAPE). From 36 to 51 DAPE, B was omitted from the nutrient solution. Petioles from young leaves and floral bud peduncles (first position of the first sympodial) were sampled and the cross-section anatomy observed under an optical microscope. The number of vascular bundles of the petiole was decreased in B-deficient plants and the xylem was disorganized. Phloem elements in the peduncle vascular cylinder of B-deficient plants did not show clear differentiation. The few xylem elements that were formed were also disorganized. Modifications caused by B deficiency may have impaired B and photosynthate translocation into new cotton growth. Boron accumulation in the shoot of B-deficient plants suggested that there was some B translocation within the plant. It could be inferred that cotton growth would be impaired by the decrease in carbohydrate translocation rather than by B deficiency in the tissue alone. 相似文献
1000.
Henrique Nery Cipriani Ana Rosa Ribeiro Bastos Janice Guedes de Carvalho Alisson Lucrécio da Costa Nilma Portela Oliveira 《Journal of plant nutrition》2013,36(11):1618-1638
A greenhouse experiment was carried out to evaluate chromium (Cr) toxicity in urograndis (Eucalyptus urophylla S. T. Blake x grandis W. Hill ex. Maiden). Chromium nitrate was amended to Clark's nutrient solution (0.00, 0.04, 0.08, 0.16, 0.32 and 0.64 mmol L?1 Cr), which was used to breed one urograndis cutting per pot (four replications). Regression analysis revealed that Cr rates of 0.08 mmol L?1 or higher significantly decreased (P < 0.01) dry matter yield of shoot and root. Chromium accumulation order in plant was: root > stem > leaves. Critical Cr toxicity level in leaves was 0.74 mg kg?1. Uptake and translocation of nutrients were affected differently by Cr. Mostly have their uptake reduced due to root damage. Magnesium, iron and manganese translocation increases, supposedly to maintain normal photosynthetic activity. Wilting is the main visual symptom of Cr toxicity. Urograndis may be suitable for contaminated sites phytostabilization and receive industrial waste fertilization. 相似文献