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排序方式: 共有726条查询结果,搜索用时 265 毫秒
241.
Marco Aldo Ortenzi Stefano Antenucci Stefania Marzorati Lucia Panzella Silvia Molino Jos ngel Rufin-Henares Alessandra Napolitano Luisella Verotta 《Molecules (Basel, Switzerland)》2021,26(2)
Among bioactive phytochemicals, ellagic acid (EA) is one of the most controversial because its high antioxidant and cancer-preventing effects are strongly inhibited by low gastrointestinal absorption and rapid excretion. Strategies toward an increase of solubility in water and bioavailability, while preserving its structural integrity and warranting its controlled release at the physiological targets, are therefore largely pursued. In this work, EA lysine salt at 1:4 molar ratio (EALYS), exhibiting a more than 400 times increase of water solubility with respect to literature reports, was incorporated at 10% in low methoxylated (LM) and high methoxylated (HM) pectin films. The release of EA in PBS at pH 7.4 from both film preparations was comparable and reached 15% of the loaded compound over 2 h. Under simulated gastric conditions, release of EA from HM and LM pectin films was minimal at gastric pH, whereas higher concentrations—up to 300 μM, corresponding to ca. 50% of the overall content—were obtained in the case of the HM pectin film after 2 h incubation at the slightly alkaline pH of small intestine environment, with the enzyme and bile salt components enhancing the release. EALYS pectin films showed a good prebiotic activity as evaluated by determination of short chain fatty acids (SCFAs) levels following microbial fermentation, with a low but significant increase of the effects produced by the pectins themselves. Overall, these results highlight pectin films loaded with EALYS salt as a promising formulation to improve administration and controlled release of the compound. 相似文献
242.
Domenico Iacopetta Alessia Catalano Jessica Ceramella Carmela Saturnino Lara Salvagno Ileana Ielo Dario Drommi Elisabetta Scali Maria Rosaria Plutino Giuseppe Rosace Maria Stefania Sinicropi 《Molecules (Basel, Switzerland)》2021,26(9)
In the late 1930s and early 1940s, it was discovered that the substitution on aromatic rings of hydrogen atoms with chlorine yielded a novel chemistry of antimicrobials. However, within a few years, many of these compounds and formulations showed adverse effects, including human toxicity, ecotoxicity, and unwanted environmental persistence and bioaccumulation, quickly leading to regulatory bans and phase-outs. Among these, the triclocarban, a polychlorinated aromatic antimicrobial agent, was employed as a major ingredient of toys, clothing, food packaging materials, food industry floors, medical supplies, and especially of personal care products, such as soaps, toothpaste, and shampoo. Triclocarban has been widely used for over 50 years, but only recently some concerns were raised about its endocrine disruptive properties. In September 2016, the U.S. Food and Drug Administration banned its use in over-the-counter hand and body washes because of its toxicity. The withdrawal of triclocarban has prompted the efforts to search for new antimicrobial compounds and several analogues of triclocarban have also been studied. In this review, an examination of different facets of triclocarban and its analogues will be analyzed. 相似文献
243.
Cariati E Forni A Biella S Metrangolo P Meyer F Resnati G Righetto S Tordin E Ugo R 《Chemical communications (Cambridge, England)》2007,(25):2590-2592
As a function of the ability of the solvent to behave as acceptor of halogen bonding, the NLO-phores under study give rise to microbeta(lambda) values ranging from +192 x 10(-48) esu to -465 x 10(-48) esu. 相似文献
244.
245.
Monica Conti Stefania Gatti Vittorino Pata 《Central European Journal of Mathematics》2007,5(4):720-732
This note is concerned with the linear Volterra equation of hyperbolic type
on the whole space ℝ
N
. New results concerning the decay of the associated energy as time goes to infinity were established.
相似文献
246.
Gennari O Montesano D Salzano A Albrizio S Grumetto L 《Biomedical chromatography : BMC》2011,25(12):1315-1318
A method for the determination of dimethyl fumarate (DMF) in desiccant and antimould sachets, employed for protecting consumer products from humidity and mould, has been developed. The method is based on a solid–liquid extraction followed by HPLC‐UV analysis. The method was validated with respect to recovery, linearity, limits of detection and quantitation and precision. The recovery was 98%. The correlation coefficient value (r) was equal to 0.94. Both intra‐ and inter‐day precisions were studied at several concentration levels, being satisfactory in all cases (RSD < 5). Limits of detection and quantification values were in the low microgram per gram level, thus allowing the determination of DMF at concentrations below the limit established (0.1 mg/kg) by the recent EU Directive (Decision 2009/251/EC). The proposed procedure was applied for the determination of the target compound in 41 desiccant and antimould samples. DMF was detected in 39.0% of samples and its content in many samples exceeded the legal limits. The results of our analysis highlight the high risk of exposure to this powerful allergic sensitizer for consumers. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
247.
Attanasi OA Favi G Mantellini F Moscatelli G Santeusanio S 《The Journal of organic chemistry》2011,76(8):2860-2866
A new and efficient synthesis of polysubstituted pyrroles by a sequential one-pot three-component reaction between primary aliphatic amines, active methylene compounds, and 1,2-diaza-1,3-dienes (DDs) is reported. The reactions were performed without catalyst and under solvent-free conditions with complete control of pathway selectivity. Notably, the ready availability of the starting materials and the high level of practicability of the reaction and work up make this approach an attractive complementary method for access to unknown polysubstituted pyrroles. 相似文献
248.
A highly stereoselective trichlorosilane-mediated reduction of N-benzyl enamines was developed; the combination of a low cost, easy to make metal-free catalyst and an inexpensive chiral auxiliary allowed to perform the reaction on substrates with different structural features often with total control of the stereoselectivity. By easy deprotection through hydrogenolysis followed by conversion of β-aminoester to 2-azetidinones, the synthesis of enantiomerically pure β-lactams (>98% e.e.) was successfully accomplished. 相似文献
249.
Ferro S Grazia SD De Luca L Gitto R Faliti CE Debyzer Z Chimirri A 《Molecules (Basel, Switzerland)》2011,16(8):6858-6870
Integrase (IN) represents a clinically validated target for the development of antivirals against human immunodeficiency virus (HIV). In recent years our research group has been engaged in the stucture-function study of this enzyme and in the development of some three-dimensional pharmacophore models which have led to the identification of a large series of potent HIV-1 integrase strand-transfer inhibitors (INSTIs) bearing an indole core. To gain a better understanding of the structure-activity relationships (SARs), herein we report the design and microwave-assisted synthesis of a novel series of 1-H-benzylindole derivatives. 相似文献
250.
Riva E Rencurosi A Gagliardi S Passarella D Martinelli M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(22):6221-6226
An efficient total synthesis of the natural alkaloid (+)-dumetorine by using flow technology is described. The process entailed five separate steps starting from the enantiopure (S)-2-(piperidin-2-yl)ethanol 4 with 29% overall yield. Most of the reactions were carried out by exploiting solvent superheating and by using packed columns of immobilized reagents or scavengers to minimize handling. New protocols for performing classical reactions under continuous flow are disclosed: the ring-closing metathesis reaction with a novel polyethylene glycol-supported Hoveyda catalyst and the unprecedented flow deprotection/Eschweiler-Clarke methylation sequence. The new protocols developed for the synthesis of (+)-dumetorine were applied to the synthesis of its simplified natural congeners (-)-sedamine and (+)-sedridine. 相似文献