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关键词： Macrocycle   Principal component analysis   Synthesis   Antiproliferative  

摘要： A macrocyclic motif fosters productive protein-small molecule interactions. There are numerous examples of both natural product and designed, synthetic macrocycles that modulate the immune system, slow microbial infection, or kill eukaryotic cells. Reported here are the synthesis, physicochemical characterization, and anti-proliferative activity of a group of [13]-macrodilactones decorated with a pendant biaryl moiety. Biaryl analogs were prepared by Suzuki reactions conducted on a common intermediate that contained a bromophenyl unit alpha to one of the carbonyls of the [13]-macrodilactone. Principal component analysis placed the new compounds in physicochemical context relative to a variety of pharmaceuticals and natural products. Modest inhibition of proliferation was observed in ASZ cells, a murine basal cell carcinoma line. This work underscores the value of an approach toward the identification of bioactive compounds that places the evaluation of physicochemical parameters early in the search process.

关键词： Anthocyanins   Maturity index   Oil content   Oleogenesis   Organic acids   Phenolic composition   Ripening   Sugars  

摘要： Analytical characterization of the ripening process is prerequisite to establishing cultivar-specific harvest maturity windows and safeguarding the quality of olive products. In this context, we profiled the ripening of select Cypriot olive (Olea europaea L.) cultivars 'Ladoelia', 'Kato Drys' and 'Korakou' juxtaposed against introduced 'Koroneiki'. Fruit skin and flesh color-based maturity index (MI) evolved linearly over time but differentially among local cultivars. Anthocyanin content exhibited better correspondence to MI with progressive maturity. Cultivars varied widely in their sugar content (60.2-180.9 mg g(-1) dw) and their fructose/glucose ratio, which impacted their relative sweetness. Putative connection of declining mannitol levels with oleogenesis during ripening was not supported by 'Korakou', wherein mannitol declined without concomitant oil accumulation. However, fruit firmness correlated negatively with oil content prompting harvest of table olives before oil peak. Succinic and oxalic acid levels may constitute valuable cultivar signature traits. Decline pattern in total phenolic content (TPC) during ripening was cultivar-specific, with oleuropein, rutin and hydroxytyrosol constituting the major constituents in diminishing abundance. No cultivar differences were observed in rutin content, while hydroxytyrosol and tyrosol levels were independent of maturity. At MI3, 'Ladoelia' had higher total phenolic content (TPC) than 'Korakou' and 'Kato Drys' but inferior to 'Koroneikr (12.3, 9.9, 2.5 and 20.4 g kg(-1) dw, respectively). Oleuropein relative content in 'Ladoelia' (85.6 %TPC) was higher than 'Kato Drys' (63.6 %TPC) and 'Korakou' (59.2 %TPC). 'Ladoelia' exhibited superior but maturity-dependent phenolic acids content. Our results corroborate a cultivar-specific application of MI supported by additional physicochemical parameters of maturity. The current findings may facilitate cultivar and productspecific integrative harvest maturity indices, which

关键词： Clay mineral   Neutron spectroscopy   Water mobility   Decomposition kinetics   Nanocarrier  

摘要： Clay minerals such as fluorohectorite (FHt) have come into prominence as drug carrier systems due to their layered structure and excellent cation exchange capabilities. Water present in the interlayers of FHt is believed to facilitate the uptake of bio-active molecules in these systems, yet details of this interaction are not well understood. To shed light into this question, using quasi-elastic neutron scattering and the jump diffusion model, we determined the diffusion coefficients and the residence time of water in this synthetic smectite clay. We demonstrate how different interlayer cations (Li+, Na+ and Ni2+) and different hydration levels influenced water mobility in FHt. By means of the elastic window method and analysis of the thermal decomposition of samples with the drug Ciprofloxacin intercalated at pH 2 in LiFHt, we confirmed that the intercalation process removed most of the interlayer water previously present in the clay. Based on the Kissinger procedure, we also showed that thermal decomposition of the intercalated drug was activated at lower temperature. These findings are discussed in relation to the drug's shelf life and might aid in the selection of clay systems for use as nanocarrier.

关键词： Modern oil paints   Portable-EDXRF   mu-Raman   FTIR   GC-MS   Erucic acid   P/S   Linseed oil   Safflower oil  

摘要： The study and the characterisation of modern and contemporary oil paintings is still a challenging issue, in particular considering the significant changes in paint production across the 19th and 20th centuries. This paper presents the results of the first physico-chemical integrated study of the artistic materials used in six paintings from the School of Art and Higher Design of Valencia (Escola d'Art i Superior de Disseny, EASDValencia), artworks created between 1871 and 1943 by four famous Valencian artists: Salustiano Asenso Arozarena, Salvador Abril I Blasco, Enrique Navas Escuriet and Jose Bellver Delmas. A wide range of inorganic and organic compounds was identified through a multi-analytical approach by means of visible reflectance spectroscopy, XRF, mu-Raman, FTIR and GC-MS. The investigation on the binding media suggests the use of commercial paint formulations including mixtures of drying, slow-and non-drying oils and the presence of GumArabic as well. Traditional pigments (such as vermillion, earth pigments, leadwhite) and modern pigments (such as zinc white, cobalt and chromium-based pigments) were identified together with fillers and extenders. Degradation products, in particular zinc and lead soaps having strong conservation implications, were also detected. This work, focusing on the identification of the palettes and the bindingmedia used by the selected artists, aimsat providingmeaningful data and interesting case studies that are useful beyond the Valencian painters solely. This study provides newinsight into the use of 19th-20th century commercial oil paints and the selection of painters' palette and their artistic production techniques. Besides, this work highlights the necessity of a multi-analytical approach to obtain valuable information for documentation and preventive conservation. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Chitosan   Fly ash   Tripolyphosphate   Reactive red 120 dye   Adsorption   Box Behnken design  

摘要： Chitosan (CS) was physically modified with fly ash (FA) powder and subjected to chemical cross-linking reaction with tripolyphosphate (TPP) to produce a cross-linked CS-TPP/FA composite as adsorbent for removal of reactive orange 120 (RR120) dye. Different ratios of FA such as 25% FA particles (CS-TPP/FA-25) and 50% FA particles (CS-TPP/FA-50) were loaded into the molecular structure of CS-TPP. Box-Behnken design (BBD) was applied to optimize the input variables that affected the synthesis of the adsorbent and the adsorption of RR120 dye. These variables included FA loading (A: 0-50%), adsorbent dose (B: 0.04-0.1 g), solution pH (C: 4-10), temperature (D: 30 degrees C-60 degrees C), and time (E: 30-90 min). Results revealed that the highest removal (88.8%) of RR120 dye was achieved by CS-TPP/FA-50 at adsorbent dosage of 0.07 g, solution of pH 4, temperature of 45 degrees C, and time of 60 min. The adsorption equilibrium was described by the Freundlich model, with 165.8 mg/g at 45 degrees C as the maximum adsorption capacity of CS-TPP/FA-50 for RR120 dye. This work introduces CS-TPP/FA-50 as an ideal composite adsorbent for removal of textile dyes from the aqueous environment. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Bioactivity   Physico-chemical properties   Mechanical properties   Hydroxyapatite-silica nanobiocomposites   Biomedical applications  

摘要： High-energy ball milling was employed to prepare carbonated hydroxyapatite/silicon dioxide (CHA/SiO2) nanocomposites. Then, these nanocomposite powders were sintered at 900 and 1300 degrees C. XRD technique, FTIR spectroscopy and SEM were employed to examine the structure, molecular structure and microstructure of the sintered nanocomposites samples, respectively. Moreover, their mechanical properties were also measured. Furthermore, in vitro bioactivity and cytotoxicity of these nanocomposites were evaluated. The results indicated that the successive increases in SiO2 contents led to remarkable enhancement for densification behavior, mechanical properties and in vitro bioactivity of nanocomposites sintered at 900 degrees C. However, further increase in the sintering temperature to 1300 degrees C caused dramatic decreases in density and mechanical properties of nanocomposites. On the contrary, better bioactivity behavior was achieved. Amazingly, the obtained results revealed that the sample having the highest content of SiO2 and sintered at 900 degrees C had no toxic effects on bone-like cells while, that sintered at 1300 degrees C exhibited mild cytotoxicity. Based on the variations in the abovementioned properties, these nanocomposites can be used in different biomedical applications.

关键词： Phytochemicals   Maracuja-da-Caatinga   Passiflora cincinnata  

摘要： Passiflora cincinnata Mast cv. BRS Sertao Forte is a cultivar resultant from the genetic improvement of the species Passiflora cincinnata, popularly known as maracuja-da-Caatinga, which presents higher field yield and pulp productivity compared to the native plant and may represent an alternative to the exotic fruit market, intended for in natura consumption or industrialization. Thus, this study characterized the physicochemical composition and accessed the phenolic compounds profile and the antioxidant potential of these fruits in different suitable for consumption ripening stages. The mature pulps had a higher content of ascorbic acid (17.67 mg 100 g(-1)), sugars (3.16 %), beta-carotene (16.62 mu g 100 g(-1)) and total flavonoids (155.62 mg 100 g(-1) ). Mineral contents like K (413.34 mg 100 g(-1)) in mature pulps and Ca (40.59 mg 100 g(-1)) in pulps with intermediate maturation stood out. The major phenolics in the pulps are isoquercetin (32.25 mu g g(-1)) and caftaric acid (7.5 mu g g(-1)) with higher content in intermediate maturing pulps, and rutin (7.46 mu g g(-1)) with higher content in the mature pulps. These bioactive compounds contribute to the antioxidant activity observed in the ORAC, DPPH and FRAP assays. It is concluded that, when compared to other Passiflora species, the passion fruit 'BRS Sertao Forte' is a fruit with distinct mineral contents such as K and Ca and bioactive compounds, and it has promising potential for cultivation in semiarid regions.

关键词： Carvacrol   Zein   Lecithin   Antioxidant   SW480 cell line   Molecular docking  

摘要： Carvacrol (CV), a monoterpene possesses wide range of biological activities but has limited application due to low aqueous solubility and poor bioavailability. To address this issue and enhance bioavailability and efficacy of carvacrol, lecithin stabilized zein nanoparticles were investigated. Precipitation method was used for synthesis of nanoparticles and characterized using various techniques. CV entrapped under optimized parameters has size around 250 nm with -15 mV zeta potential. SEM studies showed nanoparticles with spherical morphology and size in accordance with DLS studies. FTIR, NMR and DSC were used to determine the molecular interaction between CV and lecithin stabilized zein nanoparticles. Molecular docking studies were performed to understand the interaction between protein and drug at molecular level. Our results demonstrated the presence of two active sites within zein, showing strong binding interactions with carvacrol. The encapsulation efficiency of 78% with loading efficiency of 13% was obtained as per HPLC and UV-Vis studies. Cytotoxicity assay indicated that the CV loaded nanoparticles induce cytotoxicity against colon cancer (SW480) cells further confirmed by acridine orange and ethidium bromide dual staining assay. Fluorescent tagged nanoparticles revealed significant cellular uptake of drug. Our results suggest that CV can be conveniently delivered via oral route after incorporating into lecithin stabilized zein nanoparticles and may prove effective for colon cancer treatment.

关键词： Sacrificial template synthesis   MIL-53(Al)   Alumina composite   Hierarchical pores   Acid-base properties   NH3 adsorption calorimetry  

摘要： Though Metal Organic Frameworks (MOF's) and MOF-derived solids have been employed in various applications, especially catalysis, there is still a constant search for better performing MOF-based hybrid catalysts. In this work, we employed sacrificial template method in synthesizing MIL-53(Al) type - porous Alumina (MA) composites that exhibit different physico-chemical and catalytic properties compared to parent solids (MIL-53 and mesoporous Al2O3). Structural investigations demonstrated that composites possess combined structure of both the parent solids. Novel composites possess hierarchical (meso- & micro-) pores, with average pore width in the range of similar to 14-16 nm. NH3 adsorption calorimetry and isopropanol test enabled deducing the possible nature and strength of acid-basic sites in composites. 'MA' composites show intermediate chemical properties and synergistic multifunctional catalytic behaviour compared to parent solids. This work reveals, for the first time, extensively tunable physico-chemical properties of a novel class of solids: "the MIL-53(Al) type - porous alumina composites" that can have a huge potential as multifunctional catalysts.

关键词： Nanofibers   Peptides and proteins   Fluorescence   Assays   Inhibitors  

摘要： To revert amyloid fibrils to their native state is a challenge in finding a solution to prevent neurodegenerative diseases. We have adopted a structure-property-energetics correlation-based approach with drugs (5-fluorouracil and hydroxyurea) having multiple hydrogen-bond donors and acceptors as inhibitors targeting different stages of bovine serum albumin fibrillation. We present here a quantitative comprehensive biophysical approach for identifying functionalities in molecules, which offers this feature in terms of polarity and hydrogen bonding. Our objective of identifying the functionality on a drug molecule that establishes effective intermolecular hydrogen bonding with beta-strands of protein fibrils was achieved by combined calorimetric, spectroscopic, volumetric, and microscopic correlations. Relationships have been established among thermodynamic signatures, F-19-NMR chemical shifts, hydrodynamic diameters, and thermal expansion coefficients to demonstrate that the open-chain molecule is a better inhibitor of fibrillation, but its efficiency decreases with the formation of amorphous aggregates, as compared to the molecule having a uracil ring. The results have provided quantitative insights into the role of polarity and hydrogen bonding in prevention of the fibrillation process. The approach adopted here highlights the physical chemistry underlying such biologically important processes and hence has significance in deriving guidelines for rational drug design.