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81.
82.
In the present study, we evaluated chemical, nutritional, sensory and textural characteristics of table olives of an Italian double-aptitude olive cultivar ( Olea europaea  L. cv. Intosso d'Abruzzo ). The aim of this work was to focus some physico-chemical characteristics of this end product in order to enhance the value of this fruit from a nutritional point of view. These table olives are fruits with an appreciable content of fibre (2.6 g/100 g) and natural antioxidants such as polyphenols (167.8 mg/100 g) and α-tocopherol (6.44 mg/100 g). In this cultivar, oil content is high (17.5 g/100 g), such as MUFA (13.6 g/100 g). The protein content is low (1 g/100 g), but nutritional quality is high for the presence of essential amino acids.  相似文献   
83.
Integrating multiple functionalities into individual nanoscale complexes is of tremendous importance in biomedicine, expanding the capabilities of nanoscale structures to perform multiple parallel tasks. Here, the ability to enhance two different imaging technologies simultaneously—fluorescence optical imaging and magnetic resonance imaging—with antibody targeting and photothermal therapeutic actuation is combined all within the same nanoshell‐based complex. The nanocomplexes are constructed by coating a gold nanoshell with a silica epilayer doped with Fe3O4 and the fluorophore ICG, which results in a high T2 relaxivity (390 mM ?1 s?1) and 45× fluorescence enhancement of ICG. Bioconjugate nanocomplexes target HER2+ cells and induce photothermal cell death upon near‐IR illumination.  相似文献   
84.
The interactions of arsenic species with platinum and porous carbon electrodes were investigated with an electrochemical quartz crystal microbalance (EQCM) and cyclic voltammetry in alkaline solutions. It is shown that the redox reactions in arsenic-containing solutions, due to arsenic reduction/deposition, oxidation/desorption, and electrocatalyzed oxidation by Pt can be readily distinguished with the EQCM. This approach was used to show that the arsenic redox reactions on the carbon electrode are mechanistically similar to that on the bare Pt electrode. This could not be concluded with just classical cyclic voltammetry alone due to the obfuscation of the faradaic features by the large capacitative effects of the carbon double layer.For the porous carbon electrode, a continual mass loss was always observed during potential cycling, with or without arsenic in the solution. This was attributed to electrogasification of the carbon. The apparent mass loss per cycle was observed to decrease with increasing arsenic concentration due to a net mass increase in adsorbed arsenic per cycle that increased with arsenic concentration, offsetting the carbon mass loss. Additional carbon adsorption sites involved in arsenic species interactions are created during electrogasification, thereby augmenting the net uptake of arsenic per cycle.It is demonstrated that EQCM, and in particular the information given by the behavior of the time derivative of the mass vs. potential, or massogram, is very useful for distinguishing arsenic species interactions with carbon electrodes. It may also prove to be effective for investigating redox/adsorption/desorption behavior of other species in solution with carbon materials as well.  相似文献   
85.
Sulfolobus solfataricus protein disulphide oxidoreductase (SsPDO)contains three disulphide bridges linking residues C41XXC44,C155XXC158, C173XXXXC178. To get information on the role playedby these cross-links in determining the structural and functionalproperties of the protein, we performed site-directed mutagenesison Cys residues and investigated the changes in folding, stabilityand functional features of the mutants and analysed the resultswith computational analysis. The reductase activity of SsPDOand its mutants was evaluated by insulin and thioredoxin reductaseassays also coupled with peroxiredoxin Bcp1 of S. solfataricus.The three-dimensional model of SsPDO was constructed and correlatedwith circular dichroism data and functional results. Biochemicalanalysis indicated a key function for the redox site constitutedby Cys155 and Cys158. To discriminate between the role of thetwo cysteine residues, each cysteine was mutagenised and thebehaviour of the single mutants was investigated elucidatingthe basis of the electron-shuffling mechanism for SsPDO. Finally,cysteine pK values were calculated and the accessible surfacefor the cysteine side chains in the reduced form was measured,showing higher reactivity and solvent exposure for Cys155.  相似文献   
86.
Red wine has been reported to exert beneficial effects in preventing cardiovascular diseases probably due to their polyphenols constituents. The vasorelaxant capacity and phenolic composition of four monovarietal young red wines Merlot, Tempranillo, Garnacha and Cabernet-Sauvignon obtained from grapes from 2004 vintage, cultivated under the same climatic and agricultural conditions, wine-making technology and storage conditions, were determined using vascular reactivity assay in rat aortic and high-performance liquid chromatography, respectively. Primary cultures of vascular smooth muscle cells from Wistar rats were also used to evaluate their survival prevention activity as well. Every studied wine present vasorelaxation effect, but the higher value corresponds to the analyzed Merlot wine, especially rich in phenolic compounds, mainly catechins and oligomeric proanthocyanidins and anthocyanin glycosides. This study further demonstrated previous investigations about the phenolic composition of wines relation with their vasorelaxation activity.  相似文献   
87.
The health benefits of whole grain consumption can be partly attributed to the inclusion of the bran or outer-layers of the grain rich in dietary fibre. Fibre is fermented in the colon, leading to the production of beneficial metabolites, such as short-chain fatty acids (SCFA). The effect of five different types of bread on the SCFA production was studied in an in vitro model of human colon. Additionally, the postprandial effects of two selected breads on the SCFA plasma concentrations were investigated in men. A higher in vitro production of butyrate was induced by wholemeal wheat bread with bioprocessed bran than by native bran. The increase in butyrate seemed to be in exchange for propionate, whilst the total SCFA production remained similar. However, differences between the two breads in the postprandial butyrate concentrations could not be detected in peripheral blood of men, probably due to an effective utilisation by colonocytes.  相似文献   
88.
A new analytical method, using pressurised liquid extraction (PLE) and liquid chromatography–tandem mass spectrometry (LC–MS/MS), was developed for the simultaneous determination of bisphenol A (BPA), octylphenol (OP) and nonylphenol (NP) in powdered infant formulas (IF) and powdered skimmed milk (PM). The analytes were extracted by PLE, using this optimised conditions: ethyl acetate as solvent, 70 °C of temperature, reversed-phase silica C18 as dispersing agent and three cycles of extraction. The extracts were then injected in LC–MS/MS using a Gemini C18 column and a mixture of 5% water and 95% methanol/acetonitrile, both with 0.1% ammonia, as a mobile phase. Recoveries at different fortification levels (0.5 and 0.05 mg kg−1), were between 89% and 92% for BPA, 84 and 98% for OP, and 93% and 101% for NP. The method was applied to the analysis of samples of PM and IF, bought in Italian and Spanish markets. In positive samples, phenols concentration ranged from 0.07 to 1.29 mg kg−1 for BPA, from 0.028 to 1.55 mg kg−1 for OP and from 0.026 to 1.47 mg kg−1 for NP.  相似文献   
89.
In this study, the polymer/MWCNT nanocomposites were synthesized from the pristine MWCNT and polymer binders using functionalization with solution processing methods. The synthesized polymer/MWCNT nanocomposites exhibited high specific surface areas than the pristine MWCNT. The MWCNT/Nafion nanocomposite attributed to the maximum peak current at 5.795 × 10?5 (A) while the peak current of MWCNT/PBI was obtained at 3.662 × 10?5 (A). Moreover, polymer/MWCNT based electrocatalysts performed better electrochemical activity because of polymers binders can assist electrochemical interaction using the high surface areas of the catalyst supporting material. Also, the MEAs fabricated using the hot pressing method, while the acid doped PBI membrane sandwiched between the electrodes. The fabricated MEAs were successfully demonstrated in a single cell and found capable of measuring a maximum power density of 112.10 mW/cm2 under 150 °C temperature. In conclusion, the synthesized catalyst-supporting materials enhanced the electrochemical activity and catalyst stability which fulfilling the main objective of this study.  相似文献   
90.
Quality changes in Atlantic mackerel fillets during superchilled, chilled and frozen storage focusing on lipid quality, colour and changes in low molecular weight metabolites relevant for quality and safety were studied. Low formation of oxidation products was observed in chilled (up to 7 days), superchilled (up to 14 days) and frozen storage (up to one year). Only slight formation of TBARS was measured in the samples which correlated with the increasing fillet yellowness. The profile of low molecular weight compounds, analysed by high-resolution NMR, showed clear grouping of the different samples according to both treatment and storage time. The increase in K-value was highest in the chilled samples, reaching a K-value of 93 ± 3% on day 5, exceeding the proposed limit of human consumption (80%) while superchilling reached a K-value of ca 90 % after 14 days. Frozen samples showed acceptable quality in the whole storage period.  相似文献   
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