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991.
Phytochemistry Profile,Nutritional Properties and Pharmacological Activities of Mauritia flexuosa 下载免费PDF全文
Joilane Alves Pereira Freire Karla Bruna Nogueira Torres Barros Layana Karine Farias Lima Julyanna Maciel Martins Yan de Carvalho Araújo George Laylson da Silva Oliveira Jailane de Souza Aquino Paulo Michel Pinheiro Ferreira 《Journal of food science》2016,81(11):R2611-R2622
Mauritia flexuosa L. (Arecaceae) is a popular Brazilian fruit known as “buriti” and belonging to the category of functional foods. This work reviewed the phytochemistry profile, nutritional and pharmacological activities of M. flexuosa. The main bioactive compounds reported to buriti were carotenoids, tocopherols, ascorbic acid, phenolic compounds, fiber, phytosterols, and mono‐ and poly‐unsaturated fatty acids. These compounds were mainly related to antioxidant, hypolipemiant, photoprotector, antiaggregant, antithrombotic, anti‐inflammatory, hypoglycemiant, antimicrobial, and antitumor activities. Furthermore, some compounds present in buriti fruit and its properties were tested in vitro and in vivo and showed biotechnology applications, especially for extraction of fiber, polysaccharides, pigments, antioxidants, and oil. Howerer, the buriti fruit shows great relevance to the development of new products in food, pharmaceutical and chemical industry, this fruit is still underexploited and it has need to expand its production chain and processing to encourage their consumption and utilization. 相似文献
992.
993.
Disterfano Lima Martins Barbosa Jerson Rogerio Pinheiro Vaz Daborah Aline Tavares Dias do Rio Vaz Sivio Wesley Oliveira Figueiredo Marcelo Oliveira da Silva Andre Luiz Amarante Mesquita Claudio JoseCavalcante Blanco 《能源与动力工程:英文版》2013,(8):1472-1477
The use of diffusers around the horizontal-axis wind turbines has been widely studied since the diffuser improves the power coefficient of the turbine and it is often called DAWTs (diffuser augmented wind turbines).Turbines using diffuser are called DWATs (Diffuser Augmented Turbines),and have efficiency bigger than the Betz limit (maximum energy flow extracted = 59.26%). Thus, this study presents a mathematical model describing the behavior of the velocity profile internally to a diffuser according to the characteristics of flow and geometry of a conical diffuser. The results are compared with experimental data and show good agreement. 相似文献
994.
Danielle Q. Martins Wislei R. Osório Maria E.P. Souza Rubens Caram Amauri Garcia 《Electrochimica acta》2008,53(6):2809-2817
Titanium alloys show attractive properties for biomedical applications where the most important factors are biocompatibility, corrosion resistance, low modulus of elasticity, very good strength-to-weight ratio, reasonable formability and osseointegration. The aim of this study was to investigate the effects of Zr content (7.5 and 15 wt%) on microstructure and corrosion resistance of Ti–30Nb–Zr as-cast alloy samples. The corrosion tests were carried out in a 0.9% NaCl (0.15 mol L?1) solution at 25 °C and neutral pH range. A horizontal centrifuged solidification set-up was used to obtain as-cast samples with a fine dendritic arrangement. In order to evaluate the corrosion behavior, electrochemical impedance spectroscopy (EIS), polarization curves and an equivalent circuit analysis were used. It was found that the as-cast microstructure tends to have the dendrite arm spacings reduced with increasing Zr content. The results have shown that the addition of Zr to a Ti–30Nb alloy has been efficient to stabilize the beta phase. The resulting impedance parameters and passive current densities have shown that the Ti–30Nb alloys sample without Zr addition presents a higher surface reactivity which can induce a better osseointegration than those containing Zr. 相似文献
995.
Thin films of molybdenum doped indium oxide (IMO) were deposited on glass at room temperature using an in-built three-source RF magnetron sputtering. The films were studied as a function of oxygen volume percentage (O2 vol. %; ranging from 0.0 to 17.5%) in the sputtering chamber. The as-deposited amorphous films were crystallized on post-annealing. The as-deposited films are low conducting and Hall coefficients were undetectable; whereas post-annealed films possess fairly high conductivity. The lowest transmittance (11.96% at 600 nm) observed from the films deposited without oxygen increased to a maximum of 88.01% (3.5 O2 vol. %); whereas this transmittance was decreased with the increasing O2 vol. % to as low as 81.04% (15.6 O2 vol. %); a maximum of 89.80% was obtained from the films annealed at 500 °C in open air (3.5 O2 vol. %). The optical band gap of 3.80 eV obtained from the films deposited without oxygen increased with increasing O2 vol. % to as high as 3.91 eV (17.5 O2 vol. %). A maximum of 3.92 eV was obtained from the films annealed at 300 °C in N2:H2 gas atmosphere (17.5 O2 vol. %). 相似文献
996.
Joana T. Martins Miguel A. Cerqueira Ana I. Bourbon Ana C. Pinheiro Bartolomeu W.S. Souza António A. Vicente 《Food Hydrocolloids》2012
The development of mixed systems, formed by locust bean gum (LBG), and κ-carrageenan (κ-car) can offer new interesting applications such as the development of edible films with particular properties. κ-car/LBG blend films with different ratios were developed, and their effects on films’ physical properties were assessed. Thermogravimetric analysis (TGA), X-ray diffraction (XRD) patterns, dynamic mechanical analysis (DMA) and Fourier-transform infrared (FTIR) spectroscopy techniques were used to highlight the interactions between the two polysaccharides. The addition of κ-car to LBG improved the barrier properties of the films leading to a decrease of water vapor permeability (WVP). Improved values of elongation-at-break (EB) were registered when the ratio of κ-car/LBG was 80/20 or 40/60 (% w/w). Moreover, the κ-car/LBG blend films enhance the tensile strength (TS) compared to κ-car and LBG films. FTIR results suggested that hydrogen bonds interactions between κ-car and LBG have a great influence in films’ properties e.g. moisture content, WVP. Therefore, different κ-car/LBG ratios can be used to tailor edible films with enhanced barrier and mechanical properties. 相似文献
997.
Renê O. Couto Edemilson C. ConceiçãoLuíza T. Chaul Ezequiane M.S. OliveiraFrederico S. Martins Maria Teresa F. BaraKênnia R. Rezende Suzana F. AlvesJosé R. Paula 《Food chemistry》2012,131(1):99-105
In this work, spray-dried rosemary extracts were obtained. A 33 Box-Behnken design was followed to evaluate the influence of drying conditions on the contents of chemical markers and “in vitro” antioxidant activity of the powder. Although the dry products lost some of their polyphenols, they still had antioxidant activities (IC50) ranging from 17.6 to 24.8 μg · mL−1. Analysis of variance proved that studied factors and some of their interactions significantly affected most of the quality indicators. The best combination of conditions to use for obtaining dry rosemary extracts with adequate physicochemical and functional properties involves an extract feed rate of 6 mL · min−1, a drying air inlet temperature of 140 °C and a spray nozzle air flow rate of 50 L · min−1. 相似文献
998.
Pinho C Martins ZE Petisca C Figurska AM Pinho O Ferreira IM 《The Journal of dairy research》2012,79(2):224-231
Cows' and donkey milks (raw and thermally processed) and respective whey were analysed for quantification of major proteins. Two different chromatographic approaches, size exclusion (SE-HPLC) and reversed-phase high performance liquid chromatography (RP-HPLC) both coupled to UV detection were used. Usefulness of these methods for routine control of the effect of thermal processing was evaluated. The external standard method was used to calibrate the SE-HPLC and RP-HPLC systems. Concerning quantification of β-lactoglobulin (β-lg), α-lactalbumin (α-la), lysozyme (lys), and total casein (cn), no significant differences between results obtained by SE-HPLC and by RP-HPLC (t-test, P>0·05) were observed for raw milks and whey. Heating of cows' milk promoted aggregation of denatured proteins as observed by SE-HPLC, whereas α-la and β-lg from donkey milk were stable to thermal processing at 100 °C (5 min). Lys was quantified in donkey raw milk and whey however, in thermally processed donkey milk lys was denatured and could not be quantified by HPLC. 相似文献
999.
Martins Tde C de Camargo ED Lima RG Amato MB Tsuzuki Mde S 《IEEE transactions on bio-medical engineering》2012,59(7):1861-1870
Electrical impedance tomography (EIT) is an imaging technique that attempts to reconstruct the impedance distribution inside an object from the impedance between electrodes placed on the object surface. The EIT reconstruction problem can be approached as a nonlinear nonconvex optimization problem in which one tries to maximize the matching between a simulated impedance problem and the observed data. This nonlinear optimization problem is often ill-posed, and not very suited to methods that evaluate derivatives of the objective function. It may be approached by simulated annealing (SA), but at a large computational cost due to the expensive evaluation process of the objective function, which involves a full simulation of the impedance problem at each iteration. A variation of SA is proposed in which the objective function is evaluated only partially, while ensuring boundaries on the behavior of the modified algorithm. 相似文献
1000.
Filipa S. Reis Lillian Barros Maria João Sousa Anabela Martins Isabel C. F. R. Ferreira 《Food Analytical Methods》2014,7(3):645-652
The chemical composition and the antioxidant potential of three species of wild mushrooms from Northeastern Portugal, namely Agaricus albertii, Agaricus urinascens var. excellens, and Pleurotus eryngii, were compared. Standard procedures were followed in the nutritional value evaluation, while chromatographic procedures were used to analyze free sugars, fatty acids, tocopherols, phenolic compounds, and organic acids. To assess the antioxidant potential, reducing power, radical-scavenging activity, and lipid peroxidation inhibition were evaluated. P. eryngii revealed the highest levels of macronutrients, except proteins, as also the highest sugars, tocopherols, and monounsaturated fatty acids contents. A. albertii and A. urinascens var. excellens showed similar macronutrients composition. However, A. albertii revealed the highest content in PUFA and phenolic compounds. P. eryngii revealed the highest reducing power and radical-scavenging activity and A. albertii the highest lipid peroxidation inhibition. This study provides a detailed chemical characterization and antioxidant potential evaluation of three species of wild mushrooms from Portugal not yet previously reported. Thus, this work intended to contribute to the increase of information concerning species of edible mushrooms (directed to the scientific community and general population) as well as contribute to the conservation of these resources as sources of compounds of interest. 相似文献