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561.
Syed Lal Badshah Anila Riaz Akhtar Muhammad Gülsen Tel ayan Fatih ayan Mehmet Emin Duru Nasir Ahmad Abdul-Hamid Emwas Mariusz Jaremko 《Molecules (Basel, Switzerland)》2021,26(5)
Mushroom polysaccharides are active medicinal compounds that possess immune-modulatory and anticancer properties. Currently, the mushroom polysaccharides krestin, lentinan, and polysaccharopeptides are used as anticancer drugs. They are an unexplored source of natural products with huge potential in both the medicinal and nutraceutical industries. The northern parts of Pakistan have a rich biodiversity of mushrooms that grow during different seasons of the year. Here we selected an edible Morchella esculenta (true morels) of the Ascomycota group for polysaccharide isolation and characterization. Polysaccharopeptides and polysaccharides from this mushroom were isolated using the green chemistry, hot water treatment method. Fourier transform infrared spectroscopy revealed the sugar nature and possible beta-glucan type structure of these polysaccharides. Antioxidant assays showed that the deproteinized polysaccharides have moderate free radical scavenging activity. These isolated polysaccharides exhibited good acetylcholinesterase (AChE) and butyryl cholinesterase (BChE) inhibition activities. Therefore, these polysaccharides may be valuable for the treatment of Alzheimer’s and Parkinson’s diseases. Further bioassays are needed to discover the true potential of M. esculenta polysaccharides for medicinal purposes. 相似文献
562.
Anna Grabarz Mariusz Michalczyk Wiktor Zierkiewicz Steve Scheiner 《Molecules (Basel, Switzerland)》2021,26(8)
Ab initio calculations are applied to the question as to whether a AeX5− anion (Ae = Kr, Xe) can engage in a stable complex with another anion: F−, Cl−, or CN−. The latter approaches the central Ae atom from above the molecular plane, along its C5 axis. While the electrostatic repulsion between the two anions prevents their association in the gas phase, immersion of the system in a polar medium allows dimerization to proceed. The aerogen bond is a weak one, with binding energies less than 2 kcal/mol, even in highly polar aqueous solvent. The complexes are metastable in the less polar solvents THF and DMF, with dissociation opposed by a small energy barrier. 相似文献
563.
We present general analytical expressions for the matrix elements of the atom–diatom interaction potential, expanded in terms of Legendre polynomials, in a basis set of products of two spherical harmonics, especially significant to the recently developed adiabatic variational theory for cold molecular collision experiments [J. Chem. Phys. 143, 074114 (2015); J. Phys. Chem. A 121, 2194 (2017)]. We used two approaches in our studies. The first involves the evaluation of the integral containing trigonometric functions with arbitrary powers. The second approach is based on the theorem of addition of spherical harmonics.
相似文献564.
Preparation and properties of textile materials modified with triclosan‐loaded polylactide microparticles
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Agnieszka Karaszewska Irena Kamińska Magdalena Kiwała Mariusz Gadzinowski Mateusz Gosecki Stanislaw Slomkowski 《先进技术聚合物》2017,28(9):1185-1193
A convenient and simple method for preparation of commercial nonwovens with antimicrobial properties was elaborated. The process consists in preparation of poly(l ‐lactide) microspheres (from poly(l ‐lactide) with M n = 10,560 and M w /M n = 1.39) containing triclosan (5‐chloro‐2‐(2,4‐dichlorophenoxy) phenol) and loading them onto the nonwovens. The microspheres were prepared by spray drying (D n = 3.91 μm, D w /D n = 2.43) and oil‐in‐water emulsification‐solvent evaporation method (D n = 5.84 μm, D w /D n = 1.25). Content of triclosan in microspheres ranged from 4.65 to 4.95 wt%. The antibacterial nonwovens were prepared by padding of the fibers with the microspheres using the microsphere suspension. The resulting antibacterial nonwovens were examined using inhibition zone measurement method. Inhibition zones from 4 to 9 mm indicated that the modified nonwovens had antibacterial properties against Gram (+)—Staphylococcus aureus and Gram (?)—Klebsiella pneumoniae . Nonwovens were conditioned up to 12 months at relative humidity <5%, 50%, and 100% in desiccators and up to 6 months air‐conditioning system at relative humidity = 65%. Antimicrobial activity of the modified nonwovens was examined as a function of time and air humidity. Time of conditioning has strong influence on antibacterial activity, whereas the impact of the air humidity was negligible. All nonwovens had antibacterial properties even after 12 months of conditioning. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
565.
Kamil Jatczak Mariusz Gruza Katarzyna Filip Piotr Cmoch Grzegorz Grynkiewicz 《Central European Journal of Chemistry》2014,12(12):1222-1231
Protoescigenin, the main aglycone of horse chestnut saponin mixture known as escin, was selected as substrate for exploratory chemistry towards selective protection, followed by propargyl ether formation and subsequent condensation with azido-monosaccharides, to obtain novel triazole linked conjugates of the triterpene. 相似文献
566.
Lead Film Electrode Prepared with the Use of a Reversibly Deposited Mediator Metal in Adsorptive Stripping Voltammetry of Nickel
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Katarzyna Tyszczuk‐Rotko Radovan Metelka Karel Vytřas Mariusz Barczak 《Electroanalysis》2014,26(9):2049-2056
The paper presents the first report on application of a “hybrid” lead film electrode for the adsorptive stripping voltammetric determination of Ni(II) in the presence of nioxime as a complexing agent. The strategy to create a “hybrid” electrode is based on the combination of ex situ and in situ plating methods and the use of a reversibly deposited mediator metal (Zn) for the lead film formation. The surface morphology of a new sensor was characterized by atomic force microscopy. The detection limit for Ni(II) obtained at 120 s of accumulation time was 3.9×10?11 mol L?1. The proposed method was validated for the determination of nickel in water certified reference materials with good results. 相似文献
567.
Beata Koszarna Rafał Matczak Maciej Krzeszewski Olena Vakuliuk Jan Klajn Mariusz Tasior Jan T. Nowicki Daniel T. Gryko 《Tetrahedron》2014
Derivatized indolizines efficiently prepared via direct arylation, exhibit violet, blue or green fluorescence depending on the nature of substituents. By attaching two electron-withdrawing groups to five-membered ring it is possible to access a range of multi-substituted stable indolizine-based fluorophores. Compounds featuring this scaffold display advantageous combination of optical properties including reasonable fluorescence quantum yield combined with large Stokes shifts. 相似文献
568.
Mariusz Majchrzak Milena Hybsz Sylwia Kostera Maciej Kubicki Bogdan Marciniec 《Tetrahedron letters》2014
This work describes very precise and controlled catalytic transformations as useful tools for the synthesis of new trans-π-conjugated molecular and macromolecular organosilicon compounds. Several distyryl-arenes were obtained efficiently via silylative coupling in high yields and with excellent selectivity for new E,E-bis(silyl)arenes. 相似文献
569.
Grzegorz Boczkaj Mariusz Jaszczołt Andrzej Przyjazny Marian Kamiński 《Analytical and bioanalytical chemistry》2013,405(18):6095-6103
The paper presents the results of investigations on new procedures of determination of selected cleaning additives in diesel fuel. Two procedures: one-step analysis using gas chromatography with flame ionization detection (GC-FID) or mass spectrometry (GC-MS) and a two-step procedure in which normal-phase high-performance liquid chromatography (NP-HPLC) was used for preliminary separation of the additives, were compared. The additive fraction was collected using either simple elution or eluent backflush. Final determinations were performed by GC-FID and GC-MS. The studies revealed that it was impossible to determine the investigated analytes by one-step procedures, i.e. by using solely HPLC or GC. On the other hand, the use of a two-step procedure ensures reproducible results of determinations, and the limits of quantitation are, depending on the method of fraction collection by HPLC, from 1.4–2.2 ppm (GC-MS in SIM mode) to 9.6–24.0 ppm (GC-FID). Precision and accuracy of the developed procedures are compared, and possible determination errors and shortcomings discussed. Figure
Overview of the developed method 相似文献
570.
An elastic fluid-saturated porous medium is modeled as a bundle of parallel cylindrical tubes aligned in a direction parallel to the fluid movement. The pore space is filled with viscous compressible liquid. A cell model and the theory of transient pipe flow are used to derive one-dimensional governing equations in such media. All macroscopic constants in these equations are defined by the individual material constants of the fluid and solid. The interaction force includes an additional term not found in Biot's theory. 相似文献