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71.
Fedora Grande Maria Antonietta Occhiuzzi Maria Rosaria Perri Giuseppina Ioele Bruno Rizzuti Giancarlo Statti Antonio Garofalo 《Molecules (Basel, Switzerland)》2021,26(18)
Tacle® is a citrus fruit obtained from the crossbreeding of Clementine and Tarocco cultivars. This fruit retains a promising nutraceutical potential most likely due to a high content in polyphenols, among which the main constituents are the two glycosides naringin and hesperidin. Herein, we evaluated, through an in vitro assay, the capability of Tacle extracts to inhibit the hydroxymethylglutaryl-CoA reductase enzyme, which plays a key role in cholesterol biosynthesis. The results obtained spurred us to investigate whether the anti-enzymatic activity observed may be due to a direct interaction of aglycones naringenin and hesperetin with the enzyme catalytic site. Molecular docking simulations indicated that these two compounds are able to anchor to the protein with binding modes and affinities similar to those found for statins, which represent mainstream medications against hypercholesterolemia. The overall results showed an interesting nutraceutical potential of Tacle, suggesting that its extract could be used for dietary supplementation in the treatment of moderate hypercholesterolemia. 相似文献
72.
73.
Valentina Trovato Claudio Colleoni Angela Castellano Maria Rosaria Plutino 《Journal of Sol-Gel Science and Technology》2018,87(1):27-40
Textiles represent an attractive class of materials for realizing wearable biosensors. Electronic textiles, or smart textiles, describe the convergence of electronics and textiles into fabrics, which are able to sense, compute, communicate, and actuate. As many different electronic systems can be connected to any clothing, a wearable system becomes more versatile, and the user can change its look depending on environmental changes and individual preference. In this review, we want to explain how it is possible to develop the sensing component of a wearable sensor by sol–gel method based on the use of opportune organofunctional trialkoxysilane precursors, such as 3-glycidoxypropyltrimethoxysilane. Results show that the halochromic dyestuffs are completely entrapped in the sol–gel coatings, both through chemical and physical interactions with the textile fabric. Moreover, a certain washing fastness was observed. Sensor films show excellent reproducibility, reversibility, and short response times, with dynamic ranges from pH 4.4–6.0 (Methyl Red), pH 6.0–7.0 (Nitrazine Yellow), and pH 4.5–8.3 (Litmus), respectively. 相似文献
74.
Angela?I.?López-LorenteEmail author Rosaria?A.?Picca Javier?Izquierdo Christine?Kranz Boris?Mizaikoff Cinzia?Di?Franco Soledad?Cárdenas Nicola?Cioffi Gerardo?Palazzo Antonio?Valentini 《Mikrochimica acta》2018,185(2):153
Hybrids consisting of silver nanoparticles (in varying fractions) and of TiOx/ZnO were prepared via top-down ion beam sputtering (IBS) deposition on silicon substrates. The deposited nanomaterials were characterized by scanning electron microscopy and X-ray photoelectron spectroscopy. It is shown that such composites represent a viable substrate for use in both surface enhanced Raman spectroscopy (SERS) and surface enhanced infrared absorption spectroscopy (SEIRAS), as exemplarily shown for crystal violet as the model analyte. The C-H bending mode at about 1181 cm?1 and the C-N vibration at 1361 cm?1 observed in the SERS and SEIRAS spectra, respectively, have been used as analytical signal. The substrate consisting of TiOx NPs with 33% fraction of silver provides the strongest enhancement in SERS (up to 10,000-fold), while TiOx/AgNPs with thickness of 2 and 1 nm in ion beam sputtering, respectively, provides the best sensitivity in SEIRAS. The substrates also display photocatalytic activity as shown by the degradation of adsorbed crystal violet under ultraviolet irradiation. 相似文献
75.
Rosaria Rota 《Journal of Geometry》1990,39(1-2):130-138
The aim of this paper is to characterize the strongly distributive multiplicative hyperrings. A non trivial example is provided giving a model for such hyperrings; also a characterization theorem is proved.Dedicated to G. Tallini on the occasion of his 60th birthday.Research supported by G.N.S.A.G.A. — C.N.R. 相似文献
76.
Fast GC for the analysis of citrus oils 总被引:2,自引:0,他引:2
Mondello L Casilli A Tranchida PQ Costa R Dugo P Dugo G 《Journal of chromatographic science》2004,42(8):410-416
In this investigation, the gas chromatographic (GC) analysis of citrus essential oils is carried out in 3.3 min, with a speed gain of almost 14 times in comparison with traditional GC procedures. The fast method that is developed requires the application of severe experimental conditions (accelerated temperature program rates, high inlet pressures, and split ratios) and, thus, the support of adequate instrumentation. The samples investigated can be considered to be rather complex and, although a slight loss in peak resolution is observed, the overall analytical result is excellent. All data obtained are compared with that of a conventional application on the same matrices. This is done in order to evaluate the effectiveness and advantages of fast GC achieved with narrow bore columns. 相似文献
77.
Rosaria Villano Maria Rosaria Acocella Antonio Massa Laura Palombi Arrigo Scettri 《Tetrahedron: Asymmetry》2006,17(24):3332-3334
Chiral δ-hydroxy-β-ketoesters are easily available through the enantioselective vinylogous aldol reaction of Chan’s diene promoted by a SiCl4/chiral phosphoramide catalytic system. The procedure is conveniently exploited for a very rapid approach to (+)-kavain, a natural bio-active -pyrone compound. 相似文献
78.
Di Bussolo V Caselli M Romano MR Pineschi M Crotti P 《The Journal of organic chemistry》2004,69(25):8702-8708
6-O-Trityl- (1a) and 6-(O-benzyl)-substituted epoxide (1b) derived from D-glucal were examined in their addition reactions with O-, C-, N-, and S-nucleophiles. A 1,4-regio- and beta-stereoselective or an anti 1,2-addition pathway is commonly observed depending on the ability of the nucleophile to coordinate with the oxirane oxygen. When TMSN(3) or LiN(3) are used as azide-based nucleophiles, a 1,2-syn-addition pathway is also observed. 相似文献
79.
Sol-gel nanohybrid silica particles organically modified and doped with the ruthenium species tetra-n-propylammonium perruthenate (TPAP) are highly efficient catalysts for the selective oxidation of alcohols to carbonyl groups with O(2) at low pressure in toluene. The materials are easily prepared by a one-step sol-gel process, and their catalytic performance can be optimised by tailoring the conditions of their synthesis by hydrolytic co-polycondensation of tetramethoxysilane (TMOS) and alkyltrimethoxysilanes R-Si(OMe)(3) in the presence of TPAP. Eventually, heterogeneous catalysts considerably more active than the unsupported perruthenate were obtained, while also being leach-proof and recyclable. The correlation between the materials' activity, surface polarity and textural properties suggests valuable information on the chemical behaviour of sol-gel catalytic materials in oxidation catalysis; this is of interest in view of the importance of efficient solid catalysts for the selective oxidation of alcohols with O(2). 相似文献
80.
Antonino Scurria Marzia Sciortino Ana Rosa Garcia Mario Pagliaro Giuseppe Avellone Alexandra Fidalgo Lorenzo Albanese Francesco Meneguzzo Rosaria Ciriminna Laura M. Ilharco 《Molecules (Basel, Switzerland)》2022,27(10)
DRIFT, HPLC-MS, and SPME-GC/MS analyses were used to unveil the structure and the main functional compounds of red (blood) orange (Citrus sinensis) and bitter orange (Citrus aurantium). The IntegroPectin samples show evidence that these new citrus pectins are comprised of pectin rich in RG-I hairy regions functionalized with citrus biophenols, chiefly flavonoids and volatile molecules, mostly terpenes. Remarkably, IntegroPectin from the peel of fresh bitter oranges is the first high methoxyl citrus pectin extracted via hydrodynamic cavitation, whereas the red orange IntegroPectin is a low methoxyl pectin. C. aurantium IntegroPectin has a uniquely high concentration of adsorbed flavonoids, especially the flavanone glycosides hesperidin, naringin, and eriocitrin. 相似文献