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Nathalia Aceval Arriola Gielen Delfino dos Santos Elane Schwinden Prudêncio Luciano Vitali José Carlos Cunha Petrus Renata D. M. Castanho Amboni 《International Journal of Food Science & Technology》2014,49(9):2052-2060
The aim of this study was to evaluate the potential of nanofiltration for the concentration of bioactive compounds of watermelon juice. Lipophilic and hydrophilic antioxidant activities were determined through two assays, ferric reducing antioxidant power and DPPH. The content of lycopene, flavonoids and total phenolic in the concentrate samples increased with the increase in the volume reduction factor. Volume reduction factor of three showed the best performance of concentration, generating the highest values for lycopene, flavonoid and total phenolic contents. Average permeation flux was 2.3 L h?1 m?2, with continuous extraction of the concentrate at a volumetric reduction ratio of three. Lycopene showed the highest rejection coefficient (0.99), followed by flavonoids (0.96) and total phenolic content (0.65). The hydrophilic antioxidant activity values in both assays were higher than the lipophilic antioxidant activity values. A highly significant correlation was noted between the contents of flavonoids, phenolic compounds, ascorbic acid, and lycopene and their antioxidant potential in both lipophilic and hydrophilic fractions. 相似文献
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Jianmin Yuan Gregory Makris Andrew Patterson Ammara Usman Tilak Das Andrew Priest Zhongzhao Teng Sarah Hilborne Dario Prudencio Jonathan Gillard Martin Graves 《Magma (New York, N.Y.)》2018,31(1):191-199
Objective
This study aims to explore the relationship between plaque surface morphology and neovascularization using a high temporal and spatial resolution 4D contrast-enhanced MRI/MRA sequence.Materials and methods
Twenty one patients with either recent symptoms or a carotid artery stenosis ≥40% were recruited in this study. Plaque surface morphology and luminal stenosis were determined from the arterial phase MRA images. Carotid neovascularization was evaluated by a previously validated pharmacokinetic (PK) modeling approach. K trans (transfer constant) and v p (partial plasma volume) were calculated in both the adventitia and plaque.Results
Image acquisition and analysis was successfully performed in 28 arteries. Mean luminal stenosis was 44% (range 11–82%). Both adventitial and plaque K trans in ulcerated/irregular plaques were significantly higher than smooth plaques (0.079 ± 0.018 vs. 0.064 ± 0.011 min?1, p = 0.02; 0.065 ± 0.013 vs. 0.055 ± 0.010 min?1, p = 0.03, respectively). Positive correlations between adventitial K trans and v p against stenosis were observed (r = 0.44, p = 0.02; r = 0.55, p = 0.01, respectively).Conclusion
This study demonstrates the feasibility of using a single sequence to acquire both high resolution 4D CE-MRA and DCE-MRI to evaluate both plaque surface morphology and function. The results demonstrate significant relationships between lumen surface morphology and neovascularization.23.
Microfiltered cow’s milk samples were fermented with (prebiotic) and without inulin and evaluated regarding the physico-chemical composition (day 1 of storage) and rheological (days 1, 7, 14 and 21) evaluation, at temperatures of 4.0 ± 0.1 °C and 6.0 ± 0.1 °C. The addition of inulin increased the total solids content of the prebiotic fermented milk, increasing its acidity. The Power Law and Mizhari and Berk models were applied successfully to describe the flow of the fermented milks, which had characteristics of shear thinning and non-Newtonian fluid behavior. As with the addition of inulin, the storage time contributed to an increase in the apparent viscosity of the product. The prebiotic fermented milk had greater thixotropy and the hysteresis was lower with an increase in the temperature. 相似文献
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Aureanna Nairne Negrão Murakami Renata Dias de Mello Castanho Amboni Elane Schwinden Prudêncio Edna Regina Amante Carlise Beddin Fritzen-Freire Brunna Cristina Bremer Boaventura Isabella de Bona Muñoz Catia dos Santos Branco Miriam Salvador Marcelo Maraschin 《Food chemistry》2013
The aim of this study was to characterise the bioactive compounds in mate (Ilex paraguariensis St. Hil) extract and in concentrated mate extract obtained by nanofiltration (NF). Also, the impact of NF on the antioxidant activity of both mate extracts was evaluated in vitro and using eukaryotic cells of Saccharomyces cerevisiae (yeast assay). The results showed a significant increase in the contents of total phenolics (338%), chlorogenic acid (483%), theobromine (323%), caffeine (251%), chlorophyll (321%), condensed tannins (278%) and saponins (211%) in the concentrated mate extract. The concentrated mate extract showed higher in vitro antioxidant activity than the mate extract. According to the results obtained, it can be stated that the use of nanofiltration membrane is a valid approach for the concentration of biologically active compounds in aqueous extract of mate. 相似文献
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Erika Kliemann Karina Nunes de Simas Edna R. Amante Elane Schwinden Prudêncio Reinaldo F. Teófilo Márcia M. C.Ferreira & Renata D. M. C. Amboni 《International Journal of Food Science & Technology》2009,44(3):476-483
Pectin was extracted from passion fruit peel using three different acids (citric, hydrochloric or nitric) at different temperatures (40–90 °C), pH (1.2–2.6) and extraction times (10–90 min), with and without skins using a 24 factorial design. Temperature, pH and extraction time had highly significant effects on the pectin yield. A central composite design with face centring was used to optimise the extraction process conditions for citric acid without skins. Pectin yields varied from 10% to 70%. The optimal conditions for maximisation of pectin yield were the use of citric acid at 80 °C and pH 1 with an extraction time of 10 min considering model extrapolation. 相似文献
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Aureanna Nairne Negrão Murakami Renata Dias de Mello Castanho Amboni Elane Schwinden Prudêncio Edna Regina Amante Laura de Moraes Zanotta Marcelo Maraschin José Carlos Cunha Petrus Reinaldo Francisco Teófilo 《LWT》2011,44(10):2211-2216
In order to establish the parameters to obtain aqueous mate extract with the highest content of total phenolic compounds (TPC), the response surface methodology (RSM) was used. The extract obtained at 100 °C, within 3 min and with pH of 6.0 was submitted to nanofiltration to concentrate the phenolic compounds of mate (Ilex paraguariensis A. St. Hill). The total phenolic content values in the permeate and in the concentrate collected in different volumetric reduction factors (VRF) were different from those detected in the feed extract. The concentration of phenolic compounds increased when VRF was increased, reaching the highest retention index (R) of 0.99 when VRF was 4.0. The permeate and the concentrate obtained in VRF 4.0 were verified through HPLC. 4,5-dicaffeoylquinic acid and gallic acid showed retention index of 1.00 and 0.95, respectively, while 3,4-dihydroxybenzoic acid and chlorogenic acid reached 0.99 and 0.98, respectively. 相似文献
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Morte ES Costa LM Nobrega JA Korn Md 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2008,25(5):616-621
The concentrations of major (Ca, K, Mg, Na and P) and trace elements (Al, Cu and Fe) in soy protein formulations sold in Bahia (Brazil) were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES). Liquid and powdered soy protein formulation samples, both whole and light, were digested using a conventional heating program on a hot-plate. The powdered samples were prepared according to the label instructions for human consumption. A 5.0-ml aliquot of the soy protein emulsion was transferred to a borosilicate Erlenmeyer and concentrated nitric and sulfuric acid added. After a digestion time of approximately 50 min, hydrogen peroxide was added and heating continued to give a final volume of approximately 5 ml; the colorless digests were then made up to 15.0 ml with deionised water. Residual acid content was determined by acid-base titration. Good agreement between measured and certified values for all analytes in a non-fat milk powder (NIST SRM 1549) indicated that the method was suitable for major and trace elements determination in soy protein formulations. 相似文献