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61.
The present study is focused on the volatile fraction of roasted hazelnut and coffee samples, differing in botanical origins, morphological characteristics, and roasting treatments, selected as challenging matrices. Volatile components, sampled by headspace solid phase microextraction (HS-SPME), were analyzed by GC x GC-qMS, and separation results were adopted to classify, correlate, and/or compare samples and evaluate processing effects. The high-complexity sample profiles were interpreted through different methods: a group-type characterization, a direct fingerprint comparison, and a template matching to extract useful and consistent information, and advantages and limits of each specific approach were critically evaluated. The group-type analysis, focused on several known botanical and technological markers, enabled sample comparison and characterization based on their quali-quantitative distribution; it is highly reliable, because of the authentic standard confirmation, and extends the comparative procedure to trace and minor components. Fingerprint approaches (i.e., direct fingerprint comparison and template matching), on the other hand, extended sample comparisons and correlations to the whole volatiles offering an increased discrimination potential and improved sensitivity due to the wider analyte pattern considered. This study demonstrates the ability of comprehensive GC to further explore the complexity of roasted samples and emphasizes the advantages of, and the need for, a comprehensive and multidisciplinary approach to interpret the increased level of information provided by GC x GC separation in its full complexity. 相似文献
62.
Pinelli P Ieri F Vignolini P Bacci L Baronti S Romani A 《Journal of agricultural and food chemistry》2008,56(19):9127-9132
In the present study the phenolic composition of leaves, stalks, and textile fiber extracts from Urtica dioica L. is described. Taking into account the increasing demand for textile products made from natural fibers and the necessity to create sustainable "local" processing chains, an Italian project was funded to evaluate the cultivation of nettle fibers in the region of Tuscany. The leaves of two nettle samples, cultivated and wild (C and W), contain large amounts of chlorogenic and 2- O-caffeoylmalic acid, which represent 71.5 and 76.5% of total phenolics, respectively. Flavonoids are the main class in the stalks: 54.4% of total phenolics in C and 31.2% in W samples. Anthocyanins are second in quantitative importance and are present only in nettle stalks: 28.6% of total phenolics in C and 24.4% in W extracts. Characterization of phenolic compounds in nettle extracts is an important result with regard to the biological properties (antioxidant and antiradical) of these metabolites for their possible applications in various industrial activities, such as food/feed, cosmetics, phytomedicine, and textiles. 相似文献
63.
Patrizia De Gaetano Paolo Vassallo Marco Bartoli Daniele Nizzoli Andrea M. Doglioli Marcello G. Magaldi Mauro Fabiano 《Aquaculture Research》2011,42(9):1359-1370
In order to provide values of key parameters in aquaculture waste degradation modelling specifically for the Mediterranean, sampling campaigns were carried out in 2006. Accurate measurements of particulate carbon input and benthic respiration rates were performed using sediment traps and intact core incubations. The in situ measurements, compared with data from Atlantic salmon production, showed lower carbon flux and oxygen consumption, while a greater degradation capability was observed. Moreover, a temperature dependence of the benthic parameters was highlighted. Successively, the model Finite Organic Accumulation Module was used for an accurate comparison between different parameterizations. Finite Organic Accumulation Module simulates the organic carbon degradation and the net carbon accumulation on the sediment, yielding a benthic state index. In comparison with previous results, there was a decrease in benthic impacts due to minor inputs of carbon and higher mineralization rates. Moreover, a seasonal variation could be observed in the organic carbon concentration. Nevertheless, the new results remain consistent with the old ones on two points: (a) the negligible benthic impact of faeces with respect to uneaten feed and (b) the dependence of that impact on the different feed release conditions. 相似文献
64.
Jacqueline dos Santos Oliveira Luis Depablos Bruno Grossi Costa Homem Igor Machado Ferreira Robert Michael Boddey Adenilson José Paiva Márcio André Stefanelli Lara Daniel Rume Casagrande 《Grass and Forage Science》2023,78(3):416-424
To define the best grazing management strategy, it is important to assess animals' responses to variations in the structure and composition of tropical forages. This 2-year study evaluated animal response to Marandu palisadegrass (Urochloa brizantha)-calopo (Calopogonium mucunoides) mixed pastures managed under rotational grazing. Treatments consisted of three defoliation frequencies defined by rest periods interrupted at 90% (90LI), 95% (95LI) and 100% (100LI) of photosynthetically active radiation interception (LI). The stubble post-grazing height target was 15 cm. Statistical difference was declared at p < .10. The 100LI had lowest crude protein (CP) and in vitro dry matter digestibility (IVDDM) for the Marandu palisadegrass (p = <.001 both) and calopo (p = .003 and p = .067, respectively). Also, the OM digestibility decreased 7.0% in the 100LI condition than 90LI and 95LI treatment (p = .005). There was no difference in forage, grass, and legume intakes between the treatments (p > .10). The 100LI treatment decreased CP intake from grass in 33.3% (p = <.001) compared to other treatments. Greatest production of microbial N (p = .093) occurred with the 90LI treatment. The CP/digestible organic matter (DOM) ratio, urinary N excretion and retained N were lowest in the 100LI treatment (p = <.001, p = .007 and p = .014, respectively). The recommendation for grazing between 90 and 95% of LI is recommended because of greater CP intake and N utilization for the animals and improved the nutritive value of Marandu palisadegrass and calopo mixed pastures. 相似文献
65.
Camila Almeida dos Santos Rafael Cassador Monteiro Bruno Grossi Costa Homem Lucero Sarabia Salgado Daniel Rume Casagrande José Marques Pereira Cláudia de Paula Rezende Bruno José Rodrigues Alves Robert Michael Boddey 《Grass and Forage Science》2023,78(1):147-160
The use of forage legumes to contribute biologically fixed nitrogen (N) to pastures is an alternative to increase beef cattle production in tropical regions. The objective was to compare the impact of the introduction of a legume with that of N fertilizer application on forage and animal production in Brachiaria pastures. This two-year study assessed three pasture treatments: (1) mixed Marandu palisadegrass (Brachiaria brizantha [syn. Urochloa brizantha] cv. Marandu) and the legume “ovalifolium” (Desmodium ovalifolium) cv. Itabela (Mixed), (2) Marandu palisadegrass pastures with 150 kg N ha−1 (Fertilized), and (3) Marandu palisadegrass without N fertilizer (Unfertilized). Rotational stocking with a variable stocking rate was used with a target herbage allowance of 1.0 kg forage kg body weight−1. The pre-grazing green herbage mass was similar for Fertilized and Mixed pastures, with 54% and 63% more mass than Unfertilized pasture, respectively (p < .001). Cattle that grazed the fertilized pasture had the greatest average daily gain (ADG; p = .017). The stocking rate and liveweight gain per area were greatest for the Fertilized and Mixed pastures (p < .001 and p < .001, respectively). No differences between treatments were found for DM forage intake (p = .555). Organic matter digestibility was lowest (p < .001) for the Mixed pasture. The inclusion of the ovalifolium legume in the Marandu pasture had the same impact on beef cattle production as annual fertilization with 150 kg N ha−1. The potential and environmental benefits of ovalifolium are discussed. 相似文献
66.
B. G. C. Homem I. M. Ferreira M. P. Gionbelli T. F. Bernardes D. R. Casagrande M. A. S. Lara 《Grass and Forage Science》2017,72(3):481-488
Refining mathematical models may decrease labour and generate accurate estimates of leaf area in warm‐season perennial legumes. The aim of this study was to assess the use of mathematical models to determine the leaf area of four tropical forage legumes. Perennial legumes (Arachis pintoi, Stylosanthes spp., Calopogonium mucunoides and Neonotonia wightii) were collected, and an elliptical model and a corrected elliptical model were used to estimate leaf area. For comparison, linear models were also generated based on the leaflet area. The elliptical model was suitable for the initial forage peanut leaflets, while the corrected elliptical model proved suitable for estimating the area of the initial leaflets of all species as well as the terminal leaflets of forage peanut and stylo. The elliptical model could be used to estimate the area of both the initial and terminal leaflets only in stylo. Models were generated to estimate leaf area of all legumes requiring only the measurement of length and width from a single initial leaflet. In all of the studied legumes, the leaflet pairs were symmetrical, meaning the corrected elliptical model allows for the estimation of the leaflet area of each plant. 相似文献
67.
Nerinéia Dalfollo Ribeiro Skarlet De Marco Steckling Sandra Maria Maziero Maykon Júnior da Silva Greice Rosana Kläsener Cleiton Renato Casagrande 《Euphytica》2017,213(12):290
Genetically superior common bean lines will be efficiently selected with the use of more precise experimental statistics. The objectives of this study were to evaluate the experimental precision of grain yield and primary grain yield components in experiments to register common bean cultivars and identify more appropriate statistics for the selection of genetically superior common bean lines. For this purpose, 21 experiments were performed in a randomized block design in southern Brazil. A total of 156 common bean genotypes of the Mesoamerican and Andean gene pool were assessed between 1998 and 2015. Experimental precisions of grain yield and primary grain yield components were evaluated using 11 statistics. Grain yield, number of pods per plant, number of grains per pod, and mass of 100 grains were evaluated with greater experimental precision by the F-test value for genotype, heritability, coefficient of relative variation, and selective accuracy. Mass of 100 grains presented the highest experimental precision among the traits evaluated in this study. The F-test value for genotype, heritability, coefficient of relative variation, and selective accuracy allow the selection of common bean lines with genetic superiority for grain yield and primary grain yield components. Selective accuracy is the most appropriate statistic to select common bean lines with genetic superiority for grain yield and is recommended for breeding programs. 相似文献
68.
69.
Nicoletta Ferradini F. Famiani P. Proietti F. Stanica 《The Journal of Horticultural Science and Biotechnology》2013,88(6):859-865
SummaryThe effects of different BA and IBA concentrations and dark/light combinations, applied during both the last proliferating subculture (LPS) and the regeneration phase (RP), on shoot regeneration from leaves were evaluated in M.26 apple rootstock. A positive influence on caulogenesis was found with a low cytokinin/auxin ratio in the medium during the LPS. The increase in IBA concentration from 0.49 μM to 4.92 μM in the LPS, along with the absence or the use of a low cytokinin concentration (0.89 μM) in the medium, enhanced the subsequent shoot regeneration from leaves. During the RP, a concentration of 22.2 μM BA gave the best caulogenesis results. During both the LPS and the RP, high IBA concentrations were able to replace the combined effect of a low IBA concentration and dark treatment; this could indicate that dark treatments interact with the auxin metabolism in the leaf caulogenesis response. Auxin application could not reproduce all the effects of dark treatments, suggesting that dark also affects other biochemical and/or physiological aspects, such as gibberellin metabolism. Moreover, cytokinins applied during both the LPS and the RP influenced the size of regenerated shoots. 相似文献
70.
C Del Bo' P Riso A Brambilla C Gardana A Rizzolo P Simonetti G Bertolo D Klimis-Zacas M Porrini 《Journal of agricultural and food chemistry》2012,60(36):9298-9304
Blueberries ( Vaccinium corymbosum L.) are rich sources of phenolics and anthocyanins (ACNs). We investigated the absorption of ACNs after consumption of one portion (300 g) of minimally processed blueberry purée (P) obtained from blanched (BL) or unblanched (NB) berries. A repeated-measures, crossover design study was conducted on healthy human volunteers. Blood was drawn between baseline and 24 h after BL-P or NB-P consumption, while urine were collected from the day before the experiment up to 48 h. Total plasma ACN content was not significantly different, while phenolics content was higher in BL-P with respect to NB-P. The maximum ACN absorption in plasma was observed after 1.5 h from the intake of the purées and was significantly higher (p ≤ 0.05) after the intake of BL-P. Both products increased the excretion of hippuric acid in urine. In conclusion, blanching had no significant effect on total ACN content and enhanced their absorption from minimally processed purées. 相似文献