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991.
Monika Prendecka-Wrbel Dominika Pigo-Zajc Magdalena Jaszek Anna Matuszewska Dawid Stefaniuk Grzegorz Opielak Katarzyna Piotrowska Mansur Rahnama-Hezavah Teresa Maecka-Massalska 《Molecules (Basel, Switzerland)》2022,27(19)
The increase in the incidence of cancer has contributed to the search for new therapeutic methods. In recent years, the use of preparations of natural origin from medical fungi has increased. One such active substance is the extracellular, low molecular active fraction obtained from the medicinal fungus Cerrena unicolor. This study aimed to monitor the pharmacokinetics of different concentrations of substances isolated from the medicinal fungus Cerrena unicolor (ex-LMS) using the ECIS technique. In the study, mouse L929 fibroblasts and colon cancer CT26 cell lines were treated with different concentrations of the active fractions obtained from Cerrena unicolor: C1 = 2.285 (μg/mL); C2 = 22.85 (μg/mL); and C3 = 228.5 (μg/mL). This study demonstrated that the tested preparation from Cerrena unicolor had no considerable effect on the resistance, capacitance, and impedance of L929 fibroblast cells, which was an indicator of no significant effect on its physiological processes. At the same time, those parameters exhibited a decrease in colon cancer cell viability. Following our previous and current studies on Cerrena unicolor, ex-LMS extracts can be safely used in anticancer therapy or chemoprevention with no significant harmful effects on normal cells. 相似文献
992.
The cyclopentyl group was expected to act as a building block for artificial carbohydrate receptors and to participate in van der Waals contacts with the carbohydrate substrate in a similar way as observed for the pyrrolidine ring of proline in the crystal structures of protein-carbohydrate complexes. Systematic binding studies with a series of 1,3,5-trisubstituted 2,4,6-triethylbenzenes bearing various cycloalkyl groups as recognition units provided indications of the involvement of these groups in the complexation process and showed the influence of the ring size on the receptor efficiency. Representatives of compounds that exhibit a macrocyclic backbone and flexible side arms were now chosen as further model systems to investigate whether the previously observed effects represent a general trend. Binding studies with these macrocycles towards β-D-glucopyranoside, an all-equatorial substituted carbohydrate substrate, included 1H NMR spectroscopic titrations and microcalorimetric investigations. The performed studies confirmed the previously observed tendency and showed that the compound bearing cyclohexyl groups displays the best binding properties. 相似文献
993.
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995.
Plants of the genus Agrimonia L. perfectly fit the current trends in nutrition and food technology, namely, the need for raw materials with a high content of bioactive natural compounds, including polyphenols, which could be added to food. The composition of polyphenolics, including agrimoniin and flavonoids, in the aerial parts of Agrimonia procera Wallr. (A. procera) and Agrimonia eupatoria L. (A. eupatoria) (Rosaceae) was determined using HPLC-DAD-MS. The polyphenolic content of A. procera was found to be 3.9%, 3.2%, 2.9%, 1.8% and 1.1%, and that of A. eupatoria was determined to be 1.3%, 0.3%, 0.9%, 0.6% and 0.5% in the dry matter of leaves, stems, fruits, seeds and hypanthia, respectively. Except for A. procera hypanthia, agrimoniin was the main polyphenolic compound in the aerial parts of the studied Agrimonia species. Both plants are also a valuable source of flavonoid glycosides, especially apigenin, luteolin and quercetin. The obtained data indicate that both A. procera and A. eupatoria are potentially good sources of polyphenols (albeit significantly different in terms of their qualitative and quantitative composition), and may not only be a medicinal raw material, but also a valuable material for food use such as nutraceuticals or functional food ingredients. 相似文献
996.
Monika Vikal Shachi Shah Narbir Singh Meenal Gupta Pushpa Singh Yogesh Kumar 《Macromolecular Symposia》2024,413(1):2300025
In this work, nanocomposite graphitic carbon nitride/biochar is successfully prepared by physical mixing method to achieve efficient charge separation and photodegradation of RhB dye under sunlight. The biochar is synthesized by heating biomass in muffle furnace in an inert atmosphere. The graphitic carbon nitride is prepared using melamine as a precursor and heating it in a muffle furnace in air atmosphere. The structural characterizations FTIR and X-ray diffraction are done to confirm the functional groups and crystallography of prepared samples. The photodegradation of RhB dye by nanocomposite is analyzed using a UV–visible spectrophotometer under solar irradiation. It is found that the RhB dye is completely reduced by the nanocomposite in less than 6 min in the presence of sunlight. The kinetic study confirms the photodegradation of RhB dye is first order reaction and rate constant is found to be 0.31 min−1. 相似文献
997.
Induced Chirality in Canthaxanthin Aggregates Reveals Multiple Levels of Supramolecular Organization
Dr. Monika Halat Dr. Grzegorz Zając Dr. Valery Andrushchenko Prof. Petr Bouř Prof. Dr. hab. Eng. Rafal Baranski MSc Katarzyna Pajor Prof. Dr. hab. Malgorzata Baranska 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(21):e202402449
Carotenoids tend to form supramolecular aggregates via non-covalent interactions where the chirality of individual molecules is amplified to the macroscopic level. We show that this can also be achieved for non-chiral carotenoid monomers interacting with polysaccharides. The chirality induction in canthaxanthin (CAX), caused by heparin (HP) and hyaluronic acid (HA), was monitored by chiroptical spectroscopy. Electronic circular dichroism (ECD) and Raman optical activity (ROA) spectra indicated the presence of multiple carotenoid formations, such as H- and J-type aggregates. This is consistent with molecular dynamics (MD) and density functional theory (DFT) simulations of the supramolecular structures and their spectroscopic response. 相似文献
998.
Monika Poláková Dušan Joniak Miloslav Ďuriš 《Monatshefte für Chemie / Chemical Monthly》2000,131(11):1197-1205
Summary. Because of the low stability of the benzyl ester linkage in benzyl 1,2:3,5-di-O-benzylidene-α-D-glucofuranuronate during the removal of the benzylidene groups by acid hydrolysis and/or hydrogenolysis, 4-methoxybenzylidene
groups were used to block the free hydroxyl groups of D-glucuronic acid. Several benzyl esters of D-glucuronic acid were prepared, and their relative rates of acid catalyzed hydrolysis were determined by liquid-chromatographic
separation of the reaction mixture and subsequent diode array detection.
Received May 22, 2000. Accepted (revised) July 17, 2000 相似文献
999.
Katarzyna Jdrzejowska Jedrzej Kobylarczyk Dorota Glosz Emilia Kuzniak-Glanowska Dominika Tabor Monika Srebro-Hooper Jakub J. Zakrzewski Katarzyna Dziedzic-Kocurek Tadeusz M. Muzio Robert Podgajny 《Molecules (Basel, Switzerland)》2022,27(13)
Studies on molecular co-crystal type materials are important in the design and preparation of easy-to-absorb drugs, non-centrosymmetric, and chiral crystals for optical performance, liquid crystals, or plastic phases. From a fundamental point of view, such studies also provide useful information on various supramolecular synthons and molecular ordering, including metric parameters, molecular matching, energetical hierarchy, and combinatorial potential, appealing to the rational design of functional materials through structure–properties–application schemes. Co-crystal salts involving anionic d-metallate coordination complexes are moderately explored (compared to the generality of co-crystals), and in this context, we present a new series of isomorphous co-crystalline salts (PPh4)3[M(CN)6](H3PG)2·2MeCN (M = Cr, 1; Fe, 2; Co 3; H3PG = phloroglucinol, 1,3,5-trihydroxobenzene). In this study, 1–3 were characterized experimentally using SC XRD, Hirshfeld analysis, ESI-MS spectrometry, vibrational IR and Raman, 57Fe Mössbauer, electronic absorption UV-Vis-NIR, and photoluminescence spectroscopies, and theoretically with density functional theory calculations. The two-dimensional square grid-like hydrogen-bond {[M(CN)6]3−;(H3PG)2}∞ network features original {[M(CN)6]3−;(H3PG)4} supramolecular cis-bis(chelate) motifs involving: (i) two double cyclic hydrogen bond synthons M(-CN⋅⋅⋅HO-)2Ar, {[M(CN)6]3−;H2PGH}, between cis-oriented cyanido ligands of [M(CN)6]3− and resorcinol-like face of H3PG, and (ii) two single hydrogen bonds M-CN⋅⋅⋅HO-Ar, {[M(CN)6]3−;HPGH2}, involving the remaining two cyanide ligands. The occurrence of the above tectonic motif is discussed with regard to the relevant data existing in the CCDC database, including the multisite H-bond binding of [M(CN)6]3− by organic species, mononuclear coordination complexes, and polynuclear complexes. The physicochemical and computational characterization discloses notable spectral modifications under the regime of an extended hydrogen bond network. 相似文献
1000.
Magdalena Wyszyska Monika Nitsze-Wierzba Aleksandra Czelakowska Jacek Kasperski Joanna ywiec Magorzata Skucha-Nowak 《Molecules (Basel, Switzerland)》2022,27(13)
The measurement of nitric oxide (NO) in exhaled air is used in diagnostics and monitoring the pathologies not only in the respiratory system but also in the oral cavity. It has shown a huge increase in its level in asthma and diseases of the oral cavity. It seems reasonable to undertake research on the impact of inflammation on the level of NO in exhaled air. The aim of the study is to make an evidence-based review of the application of NO levels in exhaled air in the diagnosis of inflammation and treatment monitoring on the basis of selected measuring devices. Methods and Results: This paper presents an example of the application of NO measurement in exhaled air in individual human systems. Selected measuring devices, their non-invasiveness, and their advantages are described. Discussion: The usefulness of this diagnostic method in pathologies of the oral cavity was noted. Conclusions: Measuring the level of NO in exhaled air seems to be a useful diagnostic method. 相似文献