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41.
This study evaluated the feasibility of incorporating curcumin‐loaded nanoemulsions (CLNE) produced by the emulsion inversion point method in pineapple ice creams to replace artificial yellow dyes. For this purpose, ice creams with formulations: A (pineapple flavour commercial mix), B (partial replacement of commercial mix by CLNE), C (complete replacement of commercial mix by CLNE) and D (complete replacement of commercial mix by nonencapsulated curcumin) were characterized. Results showed that CLNE incorporation was a feasible alternative for reducing the use of artificial dyes, as the ice creams showed similar physicochemical and rheological properties, and formulations A and B had similar sensory acceptance.  相似文献   
42.
A magnetic field analysis is developed for three cylindrical conductor bundles in triangular and flat configurations. These configurations are compared from the point of view of per unit length series-impedance, conductor surface magnetic induction field, and conductor current distributions. Results, taking proximity and skin effects into account, are obtained from the magnetic vector potential considering on the one hand, the multi-pole method for the dielectric medium and on the other hand, Fourier series and Bessel functions developments inside the conductors. It is shown that the flat configuration is less affected by magnetic field proximity effects.  相似文献   
43.
Plectranthus barbatus, known as “falso boldo” in Brazil, is used in herbal tea or cooked as a vegetable. Infusions and decoctions of leaves from P. barbatus were analysed for their inhibition of acetylcholinesterase and their antioxidant activity. The decoction showed high inhibition activity (31% inhibition with 0.5 mg of extract/ml) and also high antioxidant activity (IC50 = 45.8 ± 0.5 μg of dry extract/ml in the DPPH test; IC50 = 69.8 ± 3.1 μg of dry extract/ml in the β-carotene–linoleic acid test). Rosmarinic acid, scutellarein 4′-methyl ether 7-O-glucuronide and (16S)-coleon E were the main constituents identified. These compounds have antiacetylcholinesterase activity. Rosmarinic acid and the scutellarein derivative have IC50 = 440 μg/ml and 1 mg/ml, respectively. One milligram per millilitre of (16S)-coleon E showed 61% inhibition of the enzyme. Other Plectranthus species, P. ecklonii, P. fructicosus, P. lanuginosus and P. verticillatus, were also analysed and the results obtained correlated with the content in rosmarinic acid.  相似文献   
44.
Although soy proteins are known to have a deleterious effect on gluten thermosetting gelation, the causes are still poorly understood. Different sources of soy protein isolates (SPI) were used to investigate the interactions between gluten and soy proteins during hydro-thermal treatments. Commercial SPI and isolates prepared from soybean lines with different subunit composition were used to study the influence of protein denaturation and subunit composition on thermoset gel formation. Rapid Visco Analyser analysis showed that replacement of gluten with more than 1% SPI decreased the peak viscosity and interfered with formation of thermoset gels. However, peak viscosity was higher for 11% gluten + 2% SPI than for 11% gluten alone, suggesting a cooperative effect. After heating and cooling, 11% gluten + 2% SPI rich in A1 and A2 subunits formed a coherent thermoset gel suggesting that the cysteine residue content of soy proteins can affect gel formation.  相似文献   
45.
BACKGROUND: This work aimed to study the chemical composition, in vitro digestibility, ruminal degradability and intestinal digestibility of nutrients of vine shoot (VS), grape marcs (GMG and GMM), white (WL), red (RL) and sherry (SL) wine lees and grape marc plus lees (GML). The effect of polyethylene glycol (PEG) on nutrient availability was also studied. RESULTS: By‐products had variable crude protein (CP) and cell walls (from 44.8 to 203 and from 122 to 741 g kg?1 dry matter (DM) for CP and neutral detergent fibre (NDF) respectively). DM and CP in vitro digestibility ranged from 0.30 to 0.91 and from 0.51 to 0.84 respectively. The effective ruminal degradability of DM and CP was low (from 0.27 to 0.36 and from 0.34 to 0.53, respectively). The intestinal digestibility of the ruminally undegraded fraction was 0.25 and 0.29 for VS and GMG, respectively. The effect of PEG was different in VS and GMG. CONCLUSION: This is the first information available on ruminal and intestinal availability of nutrients from a diversity of vine and winery by‐products. The use of a combination of the different by‐products studied may represent a valuable source of energy and protein for ruminants. Further research on the effect of diets including these by‐products on animal performance and the quality of products is necessary. Copyright © 2007 Society of Chemical Industry  相似文献   
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47.
Duarte RM  Santos EB  Duarte AC 《Water research》2003,37(17):4073-4080
In order to investigate the chemical heterogeneity of fulvic and humic acids previously isolated from a bleached Kraft pulp mill effluent, a sequential ultrafiltration (UF) scheme through four polyethersulphone membranes was applied. The unfractionated fulvic and humic acids and their fractions were characterized by UV-VIS, synchronous fluorescence (with Deltalambda=60 nm) and FTIR spectroscopies. The FTIR spectra were compared with those of lignin isolated from Eucalyptus globulus wood and from the black liquor of a Kraft pulping process. The results highlighted that fulvic acids fractions of low molecular sizes contain more lignin derived phenolic units, while those of higher molecular size exhibit a higher content of carbohydrate structures. However, the shift observed in the UV-VIS absorbance and fluorescence intensity towards higher wavelength, suggests a higher degree of conjugation of pi-bonds in the fractions of highest molecular sizes. In what concerns the humic acids size fractions, the FTIR spectra did not exhibit major differences but, as observed for the fulvic acids' fractions, UV-VIS and synchronous fluorescence spectra also suggest a higher degree of conjugation of pi-bonds in the fractions with the highest molecular sizes. It was also observed that the fulvic and humic acids fractions of the same molecular size, operationally defined by the UF process, exhibit major differences in their spectroscopic features.  相似文献   
48.
Abstract. Here we obtain difference equations for the higher order moments and cumulants of a time series {Xt} satisfying an INAR(p) model. These equations are similar to the difference equations for the higher order moments and cumulants of the bilinear time series model. We obtain the spectral and bispectral density functions for the INAR(p) process in state–space form, thus characterizing it in the frequency domain. We consider a frequency domain method – the Whittle criterion – to estimate the parameters of the INAR(p) model and illustrate it with the series of the number of epilepsy seizures of a patient.  相似文献   
49.
This study focussed on the evaluation of thermal denaturation at three different stages during soy protein isolation and the effect of subunit composition on the formation of heat-induced soy protein gels. Soy protein isolates (SPI) were prepared from 12 high protein lines, Harovinton variety and 11 derived null-lines which lacked specific glycinin (11S) and β-conglycinin (7S) protein subunits. Protein denaturation during SPI processing was monitored by differential scanning calorimetry (DSC). The results showed that hexane extraction of oil from soybean flours at 23 °C or 105 °C did cause changes in protein conformation. Rheological measurements showed that lines with different subunit compositions and 11S:7S ratio had distinctive gelation temperatures and resulted in gels with different network structures. All lines formed particulate gels at 11% protein. The 11S:7S ratio was not correlated to final stiffness, measured as the storage modulus G′, of SPI gels. Lower gelation temperatures were usually observed for 7S-rich lines. The absence of A3 and the combination of A1, A2 and A4 subunits of 11S fraction may suggest the formation of stiffer gels. A more detailed study of the frequency dependence of G′ for the various networks formed also indicated that differences in subunit composition influenced the network structures.  相似文献   
50.
Considering the increasing emergence of new contaminants, such as nanomaterials, mixing with legacy contaminants, including metal(loid)s, it becomes imperative to understand the toxic profile resulting from these interactions. This work aimed at assessing and comparing the individual and combined hepatotoxic and neurotoxic potential of titanium dioxide nanoparticles (TiO2NPs 0.75–75 mg/L), cerium oxide nanoparticles (CeO2NPs 0.075–10 μg/L), arsenic (As 0.01–2.5 mg/L), and mercury (Hg 0.5–100 mg/L) on human hepatoma (HepG2) and neuroblastoma (SH-SY5Y) cells. Viability was assessed through WST-1 (24 h) and clonogenic (7 days) assays and it was affected in a dose-, time- and cell-dependent manner. Higher concentrations caused greater toxicity, while prolonged exposure caused inhibition of cell proliferation, even at low concentrations, for both cell lines. Cell cycle progression, explored by flow cytometry 24 h post-exposure, revealed that TiO2NPs, As and Hg but not CeO2NPs, changed the profiles of SH-SY5Y and HepG2 cells in a dose-dependent manner, and that the cell cycle was, overall, more affected by exposure to mixtures. Exposure to binary mixtures revealed either potentiation or antagonistic effects depending on the composition, cell type and time of exposure. These findings prove that joint toxicity of contaminants cannot be disregarded and must be further explored.  相似文献   
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