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61.
Isoflavones have been associated with several health protective effects. In this work spontaneous legume plants were screened as putative sources of dietary isoflavones. A molecular identification of the collected species was performed throughout DNA barcoding using ITS, rbcL, rpoC1 and matK sequences. The use of a multi-locus barcoding system complemented with basic morphological information allowed the unequivocal identification at the species level of 90% of the samples. The determination of isoflavone content was performed by high-performance liquid chromatography with diode-array detection. Total average contents in the studied species were significantly different, Ononis natrix and Cytisus scoparius possessing the highest total isoflavones content (396 and 273 mg kg−1, respectively) and Lotus creticus, the lowest (20 mg kg−1). The correlation of total isoflavone content with the phylogeny of this set of plants as determined by the rpoC1 sequences was evaluated for the first time. 相似文献
62.
Santos MP França SA Santos JT Buzelle SL Bertolini GL Garófalo MA Kettelhut IC Frasson D Chaves VE Kawashita NH 《Lipids》2012,47(3):279-289
A low-protein, high-carbohydrate (LPHC) diet for 15 days increased the lipid content in the carcass and adipose tissues of
rats. The aim of this work was to investigate the mechanisms of this lipid increase in the retroperitoneal white adipose tissue
(RWAT) of these animals. The LPHC diet induced an approximately two- and tenfold increase in serum corticosterone and TNF-α,
respectively. The rate of de novo fatty acid (FA) synthesis in vivo was reduced (50%) in LPHC rats, and the lipoprotein lipase
activity increased (100%). In addition, glycerokinase activity increased (60%), and the phosphoenolpyruvate carboxykinase
content decreased (27%). Basal [U-14C]-glucose incorporation into glycerol-triacylglycerol did not differ between the groups; however, in the presence of insulin,
[U-14C]-glucose incorporation increased by 124% in adipocytes from only control rats. The reductions in IRS1 and AKT content as
well as AKT phosphorylation in the RWAT from LPHC rats and the absence of an insulin response suggest that these adipocytes
have reduced insulin sensitivity. The increase in NE turnover by 45% and the lack of a lipolytic response to NE in adipocytes
from LPHC rats imply catecholamine resistance. The data reveal that the increase in fat storage in the RWAT of LPHC rats results
from an increase in FA uptake from circulating lipoproteins and glycerol phosphorylation, which is accompanied by an impaired
lipolysis that is activated by NE. 相似文献
63.
64.
即将应用到PANDA数据获取系统与触发系统及未来BESⅢ触发系统升级的高性能计算节点[5](HPCN)符合ATCA设计规范,基于IPMI协议的智能平台管理系统为其高可靠性提供保障.自主设计的智能平台管理模块具有丰富的板级管理功能,如Hot Swap和电源分配协调,板上器件状态监控,与机箱控制器的协调通信等.主要介绍了智... 相似文献
65.
Tiago Simões João Carvalho Ana Sousa Marco F.L. Lemos Maria M. Gil Rui Pedrosa Carla Tecelão 《Journal of food science》2013,78(5):C691-C695
Proximate composition (ash, moisture, total protein, and fat contents) and fatty acid profile of Balistes capriscus (grey triggerfish) were assessed over a 6‐months period (April to September, 2011) in animals captured along the coast of Peniche (Portugal). High protein (18.9% to 21.4%) and low lipid (0.5% to 0.8%) contents were determined. The highest lipid level was found in June‐captured animals. High proportions of n‐3 polyunsaturated fatty acids (n‐3 PUFA) were observed (53.87 ± 2.00%) together with substantial quantities of oleic acid (27.58 ± 1.09%) and palmitic acid (16.52 ± 0.93%). Docosahexaenoic acid accounted for 77% of the total PUFA and was 7 times more abundant than eicosapentaenoic acid, and the n‐3/n‐6 ratio was 7.2. Gender did not influence lipid levels and the fatty acid profile, but seasonal variations were observed for PUFA and monounsaturated fatty acid contents. Overall, the nutritional properties of this underexploited species may be comparable to those of other lean fish species with higher economic value. 相似文献
66.
Maria Graças Andrade Korn Mauro Agildo Barbosa Guida José Tiago Pereira Barbosa Ednildo Andrade Torres Andréa Pires Fernandes Josué Carinhanha Caldas Santos Kelly das Graças Fernandes Dantas Joaquim Araújo Nóbrega 《Food Analytical Methods》2013,6(3):872-880
Propolis is a complex mixture of substances collected by honeybees from buds or exudates of plants, beeswax, and other constituents, as pollen and sugars. The main purpose of this study was to evaluate two digestion procedures for determination of major, minor, and trace elements (Ba, Ca, Cd, Cr, Co, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn) in natura propolis samples by inductively coupled plasma optical emission spectrometry (ICP OES). The first procedure studied was an open-vessel digestion using HNO3 + H2SO4 + H2O2 in a heating block and the second one was a microwave-assisted concentrated acid digestion using HNO3 + H2O2. Both digestion procedures led to similar results and quantitative recoveries. The residual carbon contents (RCCs) for propolis sample digests were 0.269?±?0.012 % when using the first procedure with conventional heating and 0.458?±?0.023 % by microwave-assisted closed vessel digestion, demonstrating high efficiency of both procedures. Accuracy of the results was demonstrated using a certified reference material and by comparison with a recommended official method. The t test (unpaired) at 95 % confidence level showed that there was no significant difference between determined and certified values of all analytes under investigation, except Ca concentration employing conventional procedure. The optimized microwave-assisted digestion procedure led to recoveries around 89–103 % and precision better than 5 % for most samples. The second procedure was faster, safer, and more accurate than the one based on conductive heating. Additionally, principal component analysis (PCA) was applied for checking if there was correlation between inorganic composition and source of propolis samples collected around Bahia State in the Northeast of Brazil. 相似文献
67.
Bromine, Chlorine, and Iodine Determination in Soybean and its Products by ICP-MS After Digestion Using Microwave-Induced Combustion 总被引:2,自引:0,他引:2
José Tiago Pereira Barbosa Clarissa Marques Moreira Santos Lilia dos Santos Bispo Fernanda Henrique Lyra Jorge Mauricio David Maria das Graças Andrade Korn Erico Marlon Moraes Flores 《Food Analytical Methods》2013,6(4):1065-1070
A method for bromine, chlorine, and iodine determination in soybean and related products was developed by inductively coupled plasma mass spectrometry (ICP-MS) after digestion by microwave-induced combustion (MIC). Samples were pressed as pellets and combusted using pressurized oxygen (20 bar) and ammonium nitrate solution (50 μL of 6 mol L?1) as the igniter. Analytes were absorbed in alkaline solution (100 mmol L?1 NH4OH), and a reflux step of 5 min, microwave power of 1,400 W, was applied after combustion in order to improve analyte recoveries. For Cl determination by ICP-MS, a dynamic reaction cell was used with ammonia as the reaction gas. The accuracy was evaluated using certified reference materials (CRMs) and spiked samples. Using MIC, the agreement with CRM values and spike recoveries was higher than 95 % for all analytes for certified reference materials of a similar composition (National Institute of Standards and Technology (NIST), corn bran and NIST, whole milk). Limits of detection were 0.03, 1.2, and 0.002 μg g?1 for Br, Cl, and I, respectively. The residual carbon content in the digests obtained after MIC procedure was lower than 0.5 %. Blanks were always negligible and no memory effects were observed. Digestion by MIC allowed processing up to eight samples by each run in 25 min with high efficiency of digestion providing a suitable medium for further bromine, chlorine, and iodine determination by ICP-MS. 相似文献
68.
Karen Melina Trichês Jacy Simi Júnior João Batista Calixto Ricardo Machado Tiago Pereira Rosa Emmanuel João Nogueira Leal Silva Luiz Pascoal Vansan 《Microscopy research and technique》2013,76(12):1292-1296
The aim of this study was to evaluate the biocompatibility in rat subcutaneous connective tissue of a new zinc oxide endodontic sealer (Endomethasone N) compared to those provided by Endofill and Sealer 26. Polyethylene tubes containing the test materials were implanted into dorsal subcutaneous connective tissue of Wistar albino rats. After 7 and 42 days, the implants with the surrounding tissue were collected, fixed, and processed for histologic evaluation. Sections were evaluated for the presence of inflammatory cells (poly or monomorfonuclear), blood vessels, necrosis area, and thickness of fibrous capsule. Comparisons between groups and time‐periods were performed with Kruskal–Wallis and Mann–Whitney U non‐parametric tests for 5% significance level. No differences in the biocompatibility patterns among the materials for the 2 experimental periods were observed. Independently of the sealer, the tissue behavior showed a tendency to decrease the irritation effect over time. It can be concluded that all sealers are irritant, but its toxicity decreased with time. Endomethásone N showed biocompatible characteristics comparable with those provided by Endofill and Sealer 26. Microsc. Res. Tech. 76:1292–1296, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
69.
Sintering of porous alumina obtained by biotemplate fibers for low thermal conductivity applications
Tiago Delbrücke Rogério A. Gouvêa Mário L. Moreira Cristiane W. Raubach José A. Varela Elson Longo Margarete R.F. Gonçalves Sergio Cava 《Journal of the European Ceramic Society》2013,33(6):1087-1092
In this research report, a sintering process of porous ceramic materials based on Al2O3 was employed using a method where a cation precursor solution is embedded in an organic fibrous cotton matrix. For porous green bodies, the precursor solution and cotton were annealed at temperatures in the range of 100–1600 °C using scanning electron microscopy (SEM) and thermogravimetric (TG) analysis to obtain a porous body formation and disposal process containing organic fibers and precursor solution. In a structure consisting of open pores and interconnected nanometric grains, despite the low porosity of around 40% (calculated geometrically), nitrogen physisorption determined a specific surface area of 14 m2/g, which shows much sintering of porous bodies. Energy dispersive X-ray (EDX) and X-ray diffraction (XRD) analytical methods revealed a predominant amount of α-Al2O3 in the sintered samples. Thermal properties of the sintered Al2O3 fibers were obtained by using the Laser Flash which resulted in the lower thermal conductivity obtained by α-Al2O3 and therefore improved its potential use as an insulating material. 相似文献
70.