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Nikola Horvacki Filip Andri Uro Gai Dejan urovi
ivoslav Tei Milica Fotiri Aki Duanka Milojkovi-Opsenica 《Molecules (Basel, Switzerland)》2022,27(21)
Domesticated international (standard) apple cultivars, together with resistant apple cultivars are the core of the Serbian apple production. Furthermore, autochthonous cultivars are characterized by a good adaptability to the local environmental conditions and represent a valuable source of genetic variability, as well as an important source of the gene pool for further breeding programs. Additionally, they show a higher phenolic content and a stronger antioxidant activity, in comparison to commercial cultivars. Therefore, they are more likely to be used as a functional food. The subjects of this study were seventeen samples of fruits and leaves from autochthonous apple cultivars, five international standard cultivars, and six resistant apple cultivars. The phenolic profile was determined using ultra-high performance liquid chromatography (UHPLC), coupled with a diode array detector and a TSQ Quantum Access Max triple-quadrupole mass spectrometer. A total of twenty compounds were quantified in the samples. Most of the analyzed phenolics were detected in higher amounts in the peel, compared to the mesocarp. The results of the multivariate analysis of variance (MANOVA) indicate that 5-O-caffeoylquinic acid is present in the highest amount in the mesocarp, while in the peel and leaves, quercetin-glycosides were detected in the highest amount. According to the MANOVA: phloretin, phlorizin, 5-O-caffeoylquinic acid, kaempferol, and p-coumaric acid are present in significantly higher levels in the autochthonous cultivars, compared to the standard and resistant ones (in both fruits and leaves). Therefore, these compounds can be used as chemical tracers of the apple varietal origin. 相似文献
3.
Goran Stegnjai Antonios D. Tsiailanis Milica Lazarevi Vasileios K. Gkalpinos Neda Djedovic Thomas Antoniou Suzana Stanisavljevi Mirjana Dimitrijevi Miljana Mom
ilovi ore Miljkovi Andreas G. Tzakos Bojan Jevti 《Molecules (Basel, Switzerland)》2022,27(24)
Gallic acid is a phenolic acid present in various plants, nuts, and fruits. It is well known for its anti-oxidative and anti-inflammatory properties. The phenethyl ester of gallic acid (PEGA) was synthesized with the aim of increasing the bioavailability of gallic acid, and thus its pharmacological potential. Here, the effects of PEGA on encephalitogenic cells were examined, and PEGA was found to modulate the inflammatory activities of T cells and macrophages/microglia. Specifically, PEGA reduced the release of interleukin (IL)-17 and interferon (IFN)-γ from T cells, as well as NO, and IL-6 from macrophages/microglia. Importantly, PEGA ameliorated experimental autoimmune encephalomyelitis, an animal model of chronic inflammatory disease of the central nervous system (CNS)—multiple sclerosis. Thus, PEGA is a potent anti-inflammatory compound with a perspective to be further explored in the context of CNS autoimmunity and other chronic inflammatory disorders. 相似文献
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Milica Lukic Ivana Pantelic Rolf Daniels Christel Müller-Goymann Miroslav Savic Snezana Savic 《Journal of Thermal Analysis and Calorimetry》2013,111(3):2045-2057
Mesomorphic behavior of the novel long-chain alkyl polyglucoside emulsifier comprising arachidyl alcohol (C20), behenyl alcohol (C22), and arachidyl glucoside was investigated in order to determine the prevalent stabilization mechanism and moisturizing capacity of emulsion systems based on it. For this to be accomplished thermoanalytical methods (differential scanning calorimetry and thermogravimetric analysis) coupled with microscopy, rheological, X-ray diffraction methods and a short-term in vivo study of skin hydration level were performed. Obtained results have proved that C20/C22 alkyl polyglucoside mixed emulsifier is able to provide the synergism between the two main types of lamellar phases, the liquid-crystalline (Lα), and the gel crystalline (Lβ) one, building the emulsion systems of different stability and performance. Formation of lamellar structures influenced for more than one half of water within the system to be entrapped. Conducted investigation of hydration potential in real-time conditions provided valuable information on the investigated emulsion vehicles’ moisturizing potential as well as their contribution to the skin barrier improvement. Therefore, it could be expected that emulsions based on this alkyl polyglucoside emulsifier could influence the delivery of active ingredients of both the lipophilic and hydrophilic type. The employment of thermoanalytical methods in our work suggests the possibility for thermal methods to be used more frequently in the characterization of both the novel raw materials and the belonging emulsion systems. 相似文献
6.
Božidar Čobeljić Andrej Pevec Stepan Stepanović Milica R. Milenković Iztok Turel Maja Gruden Dušanka Radanović Katarina Anđelković 《Structural chemistry》2018,29(6):1797-1806
The isothiocyanato Zn(II) complex (1) and mixed isothiocyanato/thiocyanato Cd(II) complex (2) with the condensation product of 2-acetylpyridine and trimethylammoniumacetohydrazide chloride (Girard’s T reagent) (HLCl) were investigated both experimentally and theoretically. The crystal structures of both complexes showed tridentate N2O coordination of hydrazine ligand. In complex 1 square-pyramidal coordination surrounding of Zn(II) consists of deprotonated hydrazone ligand and two isothiocyanato ligands, while in octahedral Cd(II) complex ligand is coordinated without deprotonation as a positively charged species and coordination geometry is completed with two N-coordinated and one S-coordinated NCS? anions. NMR spectroscopy and molar conductivity results for Cd(II) and Zn(II) complexes indicated their instability in solution. DFT calculations were performed to explain coordination preference and stability of complexes 1 and 2 in solid state and in solution. The obtained Cd(II) complex is the first reported mononuclear pseudohalide/halide Cd(II) complex with quinoline-/pyridine-based hydrazone ligands possessing octahedral geometry in solid state. In this complex, H-bonding has significant impact on coordination number and supramolecular assembly in solid state. 相似文献
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Milorad Stojanovic 《Journal of solid state chemistry》2007,180(3):907-914
The eutectic 7.3:2.7 molar ratio mixture of calcium and zinc metal melts at 394 °C and was explored as a solvent for the growth of new intermetallic phases for potential use as hydrogen storage materials. The reaction of nickel in this molten mixture produces two new phases—the CaCu5-related structure CaNi2Zn3 (P6/mmm, a=8.9814(5) Å, c=4.0665(5) Å) and a new cubic structure Ca21Ni2Zn36 (Fd-3m, a=21.5051(4) Å). Palladium-containing reactions produced CaPd0.85Zn1.15 with the orthorhombic TiNiSi structure type (Pnma, a=7.1728(9) Å, b=4.3949(5) Å, c=7.7430(9) Å). Reactions of platinum in the Ca/Zn mixture produce Ca6Pt3Zn5, with an orthorhombic structure related to that of W3CoB3 (Pmmn, a=13.7339(9) Å, b=4.3907(3) Å, c=10.7894(7) Å). 相似文献
9.
Parvin Zare Maria Mahrova Emilia Tojo Anja Stojanovic Wolfgang H. Binder 《Journal of polymer science. Part A, Polymer chemistry》2013,51(1):190-202
A facile synthetic route for the preparation of dicationic ethylene glycol based‐ionic liquids (ILs) via the azide/alkyne “click” reaction is presented. The copper(I) catalyzed, microwave‐assisted azide/alkyne “click” reaction between diazido‐ethylene glycols and the corresponding alkyne containing IL‐head group enables a simple preparation of different sets of poly(ethylene glycol)‐based ILs. Beside tetra‐ and hexa(ethylene glycol)‐based ILs, also oligomeric (Mn = 400 g/mol) and polymeric ILs (Mn up to 1550 g/mol) could be prepared in good yield and with full conversion of the ionic head group. The prepared ILs were extensively characterized via NMR spectroscopy and ESI‐time‐of‐flight (TOF) mass spectroscopy, revealing the formation of multiply charged ions in the negative mode. Thermal stability proved to be exceptionally high (up to 300 °C) together with low glass‐transition temperatures. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献