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991.
Adriel Ferreira da Fonseca Adolpho José Melfi Francisco Antônio Monteiro Célia Regina Montes Vagner Vidal de Almeida Uwe Herpin 《Agricultural Water Management》2007
The use of treated sewage effluent in agriculture has been a current practice in several countries. However, in Brazil, there are few studies about this subject. This research work aimed at evaluating the potential utilization of secondary-treated sewage effluent (STSE) as an alternative source of water and nitrogen (N) for Tifton 85 bermudagrass pasture. A field experiment was carried out at Lins, State of São Paulo, Brazil, for 2 years, using a randomized complete block design, with four replications and five treatments, as follows: (i) T1 (control) – irrigation with potable water and addition of mineral-N fertilizer (MNF) – 520 kg N ha−1 year−1; (ii) T2–T5 – irrigation with STSE (31.9 mg total-N L−1) and addition of MNF – 0, 171.6, 343.2 and 520 kg N ha−1 year−1, respectively. Potable water and STSE characteristics were monitored monthly; above ground grass dry matter yield (DM) and crude protein content (CP) were determined bimonthly. Increases in DM and CP were observed for the high MNF rates associated with irrigation with STSE. STSE irrigation can efficiently substitute potable water for irrigation of Tifton 85 bermudagrass pasture and, simultaneously, save 32.2–81.0% of the recommended N rate without loss of grass DM and CP yield. 相似文献
992.
Silva Ferreira AC Rodrigues P Hogg T Guedes De Pinho P 《Journal of agricultural and food chemistry》2003,51(3):727-732
Volatile sulfur compounds of 15 young port wines and 12 old port wines were determined. As there is a great difference in the pool of sulfur compounds between the two groups of wines, an experimental protocol was performed to determine which technological parameter (dissolved O(2), free SO(2) levels, pH, and time/temperature) was related with the formation/consumption of these compounds. Four sulfur compounds were selected for this purpose: dimethyl sulfide, 2-mercaptoethanol, dimethyl sulfone, and methionol. The synergistic effects of increasing temperature and O(2) at lower pH had the largest impact. Dimethyl sulfide was formed during the experimental period in the presence of O(2). Dimethyl sulfone had the same behavior. Methionol decreased significantly in the presence of O(2), but no methional was formed. 2-Mercaptoethanol, considered to be an important "off-flavor" in dry wines, also decreased during the experimental period (54 days) in the presence of O(2), and the respective disulfide was formed. These results corroborate the fact that old port wine (barrel aged) never develops "off-flavors" associated with the presence of methionol (cauliflower), 2-mercaptoethanol (rubber/burnt), or methional (cooked potato). In fact, temperature and oxygen are the major factors in the consumption of these molecules. However, some notes of "quince" and "metallic" can appear during port wine aging, and these can be associated with the presence of dimethyl sulfide. 相似文献
993.
Rui Ferreira Helena Gaspar Juan M. Gonzalez Maria I. Clara Margarida M. Santana 《植物养料与土壤学杂志》2015,178(6):953-962
Recent studies suggest an important role of thermophilic bacterial communities of the Phylum Firmicutes on soil C, N and S cycling, and a positive effect on crop productivity through the production of sulfate (SO $ _4^{2 - } $ ) and ammonium (NH $ _4^+ $ ), essential plant nutrients. Copper (Cu) is commonly supplemented to soils as a fungicide in phytosanitary treatments although its consequences to the bacterial communities is frequently overlooked. Herein, we report on the influence of temperature and Cu on the microbial communities, namely those of the Phylum Firmicutes, from a soil collected at an olive orchard in S Portugal. Community fingerprints and band identification through sequencing was combined with measurement of SO $ _4^{2 - } $ and NH $ _4^+ $ production at different supplemented amounts of Cu and at moderate and high temperatures (30°C and 50°C, respectively). Both temperature and Cu induced changes in these communities, selecting for specific bacteria. Temperature induced the dominance of Brevibacillus, and Cu addition to soil caused a reduction of SO $ _4^{2 - } $ release by soil bacteria. Ammonium production during bacterial growth at moderate and high temperatures was not affected by Cu addition. A Cu‐tolerant thermophilic isolate, belonging to the Bacillus genus, showed significant inhibition by high Cu concentrations and a reduction of NH $ _4^+ $ release during growth; genera Brevibacillus and Bacillus have been previously reported as high NH $ _4^+ $ and SO $ _4^{2 - } $ producers of the Firmicutes phylum. Results indicate that Cu treatments select specific tolerant bacterial strains which could influence natural soil fertilization in Cu‐treated orchards. 相似文献
994.
The proteins from Vigna unguiculata (L.) Walp. (cowpea) seeds were investigated. Globulins constitute over 51% of the total seed protein, with albumins composing approximately 45%. The globulins may be fractionated by native electrophoresis or anion exchange chromatography into three main components, which were termed (in decreasing order of anodic mobility) alpha-vignin, beta-vignin, and gamma-vignin. alpha-Vignin, with a sedimentation coefficient of 16.5S, is a major, nonglycosylated globulin, composed of a major 80 kDa subunit, which upon reduction, produces two polypeptides (20 and 60 kDa). beta-Vignin, with a sedimentation coefficient of 13S, is a major, glycosylated globulin, composed of two main polypeptides (55 and 60 kDa) with no disulfide bonds. Finally, gamma-vignin, a minor globulin, is composed by one main type of subunit (22 kDa), which upon reduction, is converted into a single, apparently heavier polypeptide chain (30 kDa) due to the presence of an internal disulfide bond. Immunological analyses revealed structural homology between beta-vignin and beta-conglutin (the vicilin from Lupinus seeds) but not between alpha- or gamma-vignins and their Lupinus counterparts. Haemagglutination activity toward trypsinized rabbit erythrocytes was found exclusively in the albumin fraction and was strongly inhibited by N-acetylglucosamine or chitin. 相似文献
995.
Casal S Alves MR Mendes E Oliveira MB Ferreira MA 《Journal of agricultural and food chemistry》2003,51(22):6495-6501
This work reports the results for the composition of robusta and arabica coffee species in terms of their amino acid enantiomers in the green and roasted states. The analyses were conducted for the free amino acids, as well as for the amino acids obtained after acid hydrolysis. The amino acids were extracted/hydrolyzed and isolated by SPE on strong cation exchange columns, derivatized to their N-ethoxycarbonylheptafluorobutyl esters, and analyzed by gas chromatography/FID on a Chirasil l-Val column. Multivariate analyses applied to the results showed that the free amino acids can be used as a tool for discrimination between coffee species, with a special reference to l-glutamic acid, l-tryptophan, and pipecolic acid. There is also some evidence that these compounds can be used for discrimination between green coffees subjected to different postharvest processes. It is also shown that the amino acid levels observed after acid hydrolysis can be used for the same purposes, although displaying less discriminatory power. 相似文献
996.
Mariângela Brito Freiberger Iraê Amaral Guerrini Gustavo Castoldi Lilian Guimarães de Favare 《Journal of plant nutrition》2015,38(9):1309-1322
The initial growth and mineral nutrition of the physic nut (Jatropha curcas L.) as a function of nitrogen (N) fertilization was investigated. The transplanting of seedlings was carried out in plastic pots filled with 50 dm3 of a Rhodic Hapludox, under a plastic greenhouse. In addition to a control treatment, the dosages of 0, 40, 80, 120, and 160 mg dm?3 N were tested. The results demonstrated that N fertilization for the cultivation of physic nut could be added as top dressing from 60 days after planting with a dosage of 65 mg dm?3. A SPAD index of 46 can be used as a nutritional reference to its initial development. Furthermore, the results suggested that the order of nutrient accumulation by the physic nut plants is as follows: potassium (K) > N > magnesium (Mg) > calcium (Ca) > phosphorus (P) > sulfur (S) > iron (Fe) > manganese (Mn) > boron (B) > zinc (Zn) > copper (Cu). 相似文献
997.
Margarida Arrobas Ana Marília Claro Isabel Q. Ferreira M. Ângelo Rodrigues 《Journal of plant nutrition》2015,38(14):2294-2311
Some legume species are able to utilize phosphorus (P) from sparingly soluble P sources benefiting companion crops or those following in the rotation. Lupinus albus, Vicia villosa, and a mixture of eleven annual pasture legumes were used in olive orchards as mulched cover crops as a means of increasing the soil P availability. By soil testing and growing bioindicator P plants in the next season, it was possible to detect a slight but consistent increase in soil P availability. The results indicated that the increase in soil P availability was mainly due to the mineralization of the high P content legume residues, rather than the direct effect in the rhizosphere of the living plants. The results also suggested that the good adaptation of white lupine to low P environments might be due to a high internal P use efficiency of this species, producing high dry matter yields with low P concentration in their tissues. 相似文献
998.
Rafaela Guimarães Lillian Barros Ricardo C. Calhelha Ana Maria Carvalho Maria João R. P. Queiroz Isabel C. F. R. Ferreira 《Plant foods for human nutrition (Dordrecht, Netherlands)》2014,69(1):37-42
Arbutus unedo, Prunus spinosa, Rosa micrantha and Rosa canina are good sources of phenolic compounds, including anthocyanins. These compounds have potent antioxidant properties, which have been related to anticancer activity. Herein, the in vitro antioxidant and antitumor properties of enriched phenolic extracts (non-anthocyanin phenolic compounds enriched extract- PE and anthocyanins enriched extract- AE) of the mentioned wild fruits were evaluated and compared. PE gave higher bioactive properties than the corresponding AE. It was observed a high capacity of A. unedo phenolic extract to inhibit lipid peroxidation in animal brain homogenates (EC50?=?7.21 μg/mL), as also a high antitumor potential against NCI-H460 human cell line (non-small lung cancer; GI50?=?37.68 μg/mL), which could be related to the presence of galloyl derivatives (exclusively found in this species). The bioactivity of the studied wild fruits proved to be more related to the phenolic compounds profile than to the amounts present in each extract, and could be considered in the design of new formulations of dietary supplements or functional foods. 相似文献
999.
Alessandra Mirtes Marques Neves Gon?alves Aline Brito de Lima Maria Cristina da Silva Barbosa Luiz Fernando de Camargos Júlia Teixeira de Oliveira Camila de Souza Barbosa José Augusto Ferreira Perez Villar André Carvalho Costa Isabella Viana Gomes da Silva Luciana Maria Silva Fernando de Pilla Varotti Fabio Vieira dos Santos Gustavo Henrique Ribeiro Viana 《Marine drugs》2014,12(8):4361-4378
Cancer continues to be one of the most important health problems worldwide, and the identification of novel drugs and treatments to address this disease is urgent. During recent years, marine organisms have proven to be a promising source of new compounds with action against tumoral cell lines. Here, we describe the synthesis and anticancer activity of eight new 3-alkylpyridine alkaloid (3-APA) analogs in four steps and with good yields. The key step for the synthesis of these compounds is a Williamson etherification under phase-transfer conditions. We investigated the influence of the length of the alkyl chain attached to position 3 of the pyridine ring on the cytotoxicity of these compounds. Biological assays demonstrated that compounds with an alkyl chain of ten carbon atoms (4c and 5c) were the most active against two tumoral cell lines: RKO-AS-45-1 and HeLa. Micronucleus and TUNEL assays showed that both compounds are mutagenic and induce apoptosis. In addition, Compound 5c altered the cellular actin cytoskeleton in RKO-AS-45-1 cells. The results suggest that Compounds 4c and 5c may be novel prototype anticancer agents. 相似文献
1000.
Miyahira Roberta Fontanive de Lima Pena Fabíola Fabiano Giovanna Alexandre de Oliveira Lopes Jean Ponte Luis Gustavo Saboia da Cunha Diogo Thimoteo Bezerra Rosangela Maria Neves Antunes Adriane Elisabete Costa 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(2):233-240
Plant Foods for Human Nutrition - The consumption of sprouts has increased as the germination process causes changes in the chemical composition of the seeds, improving their nutritional value. The... 相似文献