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61.
Over the past decades, natural products have emerged as promising agents with multiple biological activities. Many studies suggest the antioxidant, antiangiogenic, antiproliferative and anticancer effects of chalcones and their derivatives. Based on these findings, we decided to evaluate the effects of the newly synthetized chalcone L1 in a human cervical carcinoma cell (HeLa) model. Presented results were obtained by western blot and flow cytometric analyses, live cell imaging and antimigratory potential of L1 in HeLa cells was demonstrated by scratch assay. In the present study, we proved the role of L1 as an effective agent with antiproliferative activity supported by G2/M cell cycle arrest and apoptosis. Moreover, we proved that L1 is involved in modulating Transforming Growth Factor-β1 (TGF-β) signal transduction through Smad proteins and it also modulates other signalling pathways including Akt, JNK, p38 MAPK, and Erk1/2. The involvement of L1 in epithelial-to-mesenchymal transition was demonstrated by the regulation of N-cadherin, E-cadherin, and MMP-9 levels. Here, we also evaluated the effect of conditioned medium from BJ-5ta human foreskin fibroblasts in HeLa cell cultures with subsequent L1 treatment. Taken together, these data suggest the potential role of newly synthesized chalcone L1 as an anticancer-tumour microenvironment modulating agent.  相似文献   
62.
Consumer demand for both plant products and meat products enriched with plant raw materials is constantly increasing. Therefore, new versatile and reliable methods are needed to find and combat fraudulent practices in processed foods. The objective of this study was to identify oilseed species-specific peptide markers and meat-specific markers that were resistant to processing, for multispecies authentication of different meat and vegan food products using the proteomic LC-MS/MS method. To assess the limit of detection (LOD) for hemp proteins, cooked meatballs consisting of three meat species and hemp cake at a final concentration of up to 7.4% were examined. Hemp addition at a low concentration of below 1% was detected. The LOD for edestin subunits and albumin was 0.9% (w/w), whereas for 7S vicilin-like protein it was 4.2% (w/w). Specific heat-stable peptides unique to hemp seeds, flaxseed, nigella, pumpkin, sesame, and sunflower seeds, as well as guinea fowl, rabbit, pork, and chicken meat, were detected in different meat and vegan foods. Most of the oilseed-specific peptides were identified as processing-resistant markers belonging to 11S globulin subunits, namely conlinin, edestin, helianthinin, pumpkin vicilin-like or late embryogenesis proteins, and sesame legumin-like as well as 2S albumins and oleosin isoforms or selected enzymic proteins.  相似文献   
63.
The increase in the production and consumption of pharmaceuticals increases their presence in the global environment, which may result in direct threats to living organisms. For this reason, there is a need for new methods to analyze drugs in environmental samples. Here, a new procedure for separating and determining selected drugs (diclofenac, ibuprofen, and carbamazepine) from bottom sediment and water samples was developed. Drugs were determined by ultra-high performance liquid chromatography coupled with an ultraviolet detector (UHPLC-UV). In this work, a universal and single-step sample treatment, based on supramolecular solvents (SUPRAS), was proposed to isolate selected anticonvulsants and nonsteroidal anti-inflammatory drugs (NSAIDs) from sediment samples. The following parameters were experimentally selected: composition of the supramolecular solvent (composition THF:H2O (v/v), amount of decanoic acid), volume of extractant, sample mass, extraction time, centrifugation time, and centrifugation speed. Finally, the developed procedure was validated. A Speedisk procedure was also developed to extract selected drugs from water samples. The recovery of analytes using the SUPRAS procedure was in the range of 88.8–115%, while the recoveries of the Speedisk solid-phase extraction procedure ranged from 81.0–106%. The effectiveness of the sorption of the tested drugs by sediment was also examined.  相似文献   
64.
Electron beam (EB) irradiated wool was examined for sorption of chromic ions. Sorption increased with the adsorbed dose non-monotonously, which is a result of the generation of S-oxidized groups, secondary structure variation, and the breaking of the keratin backbone. For a dose of 400 kGy, an increase by 120 % was observed at the cystine dioxide and cysteine acid amounts. Examining sorption of unexposed wool and that irradiated with doses of 25 kGy and 40 kGy for basic, methylene blue (MB), or acidic, pyrogallol red (PR) dyes revealed that such low doses have no effect on the carboxylic or amino groups of keratin. Sorption of MB is independent of the EB treatment and is identical for both samples due to the interaction of MB amino groups with the carboxylic groups of wool; however, the sorption capacity for PR is a function of the EB treatment. The sample irradiated with the dose of 25 kGy showed higher PR sorption than that with the EB dose of 40 kGy, which was equal to that of unexposed wool. While the 25 kGy sample provided more active sites for PR interaction compared with the unexposed one, the 40 kGy sample contained already enough active sites to generate intra- and intermolecular interactions inside wool. Thus, PR adherence to the 40 kGy sample was restricted and comparable to the level of unexposed wool.  相似文献   
65.
Medicinal plants are a significant source of biological active and health protective compounds. Post-harvest treatments can affect, in different ways, the content and biological activity of such compounds. One of the most common post-harvesting methods is drying. In this study, we investigated the effect of drying method on the content of natural pigments (chlorophylls, carotenoids and anthocyanins) and on the antioxidant capacity of two traditionally used herbs, the Melissa officinalis (lemon balm) and the Urtica dioica (stinging nettle) both of them landraces collected from plants grown in Nitra region, West of Slovakia. The freeze-dried samples of both herbs exhibited the highest content of chlorophyll a (7.55 ± 0.13 mg/g dry mass for lemon balm and 9.41 ± 0.17 mg/g dry mass for stinging nettle), chlorophyll b (3.12 ± 0.28 mg/g dry mass for lemon balm and 3.34 ± 0.24 mg/g dry mass for stinging nettle) and carotenoids (2.11 ± 0.24 mg/g dry mass for lemon balm and 2.62 ± 0.06 mg/g dry mass for stinging nettle). The content of chlorophylls and carotenoids correlated with the DPPH antioxidant (radical scavenging) capacity. Higher antioxidant capacity of the lemon balm extracts compared to nettle samples was attributed to the higher content of polyphenol compounds anthocyanins. Despite the higher cost, the freeze drying (lyophilisation) was recommended as the most suitable drying method, mainly for reasons of preserving maximum pigment content and antioxidant capacity.  相似文献   
66.
Paprika powder is a good source of different carotenoids and polyphenols, which play a key role in preventing certain diseases (some kinds of cancer and cardiovascular diseases). They can also be used as natural food colorants. Organic production is characterized by strict rules, but products obtained in this way contain more bioactive compounds, such as carotenoids and polyphenols. The aim of this study was to measure and identify carotenoids and polyphenols in different paprika samples (sweet, hot, smoked, and chili) obtained by organic and conventional production. Quantitative and qualitative carotenoid and polyphenols analysis showed that the experimental samples contained different concentrations of these compounds.  相似文献   
67.
A combination of MEKC with a—highly sensitive but not commonly used—LIF detector was tested regarding the possibility of differentiation of red inks. The separation process was conducted in a fused silica capillary (id 50 μm, 60/50 cm total/effective length) in BGE consisting of 40 mM sodium borate, 20 mM SDS and 10% v/v ACN with 30 kV applied. The optimized temperature of storage and capillary was 10 and 25°C, respectively. The samples were prepared using 20 dots (ø 0.5 mm), extracted in 35 μL BGE and diluted with 30 μL of water. The proposed method showed excellent repeatability and reproducibility (RSD (tm) < 0.8 and < 2.5%, respectively). It was applied to group identification and differentiation of different brands, models, and batches of red printing, stamp, and pen inks. It was demonstrated that differentiation can be performed effectively on the basis of migration times and ratios of peak areas. The high efficiency of the developed method was indicated by discriminating power ranging from 87.3 to 98.8%, for stamp and pen inks, respectively. The results showed that the proposed procedure can be valuable for an objective examination of the red parts of questioned documents.  相似文献   
68.
We have previously shown that liquid extraction surface analysis (LESA) mass spectrometry (MS) is a technique suitable for the top-down analysis of proteins directly from intact colonies of the Gram-negative bacterium Escherichia coli K-12. Here we extend the application of LESA MS to Gram-negative Pseudomonas aeruginosa PS1054 and Gram-positive Staphylococcus aureus MSSA476, as well as two strains of E. coli (K-12 and BL21 mCherry) and an unknown species of Staphylococcus. Moreover, we demonstrate the discrimination between three species of Gram-positive Streptococcus (Streptococcus pneumoniae D39, and the viridans group Streptococcus oralis ATCC 35037 and Streptococcus gordonii ATCC35105), a recognized challenge for matrix-assisted laser desorption ionization time-of-flight MS. A range of the proteins detected were selected for top-down LESA MS/MS. Thirty-nine proteins were identified by top-down LESA MS/MS, including 16 proteins that have not previously been observed by any other technique. The potential of LESA MS for classification and characterization of novel species is illustrated by the de novo sequencing of a new protein from the unknown species of Staphylococcus.
Graphical Abstract ?
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69.
Commercial water electrolysis cells require a resistive, ion-permeable, gas-impermeable separator membrane between the electrodes to stop the hydrogen bubbles from mixing with the oxygen bubbles and vice versa. This work reviews the current status of ‘membraneless’ water electrolysis cells that safely avoid need for such a separator membrane. Three different approaches have been used to realize such cells. In the first approach, laminar flow within a microfluidic reaction chamber has been used to entrain the hydrogen and oxygen gas bubbles in separate, parallel streams that do not mix. In the second approach, closely-spaced porous electrodes have had liquid electrolyte divergently pumped through them to sweep the produced hydrogen and oxygen bubbles to different locations. In the most recent, promising approach, gas diffusion electrodes have been used to directly extract gas as it is produced, thereby avoiding discernible bubble formation and eliminating the need for a separator membrane to keep the gases separate.  相似文献   
70.
Self‐assembled bi‐ and polymetallic complexes of CoII, NiII, ZnII, and CdII were obtained by the reaction of 4,4′‐azopyridine (azpy) with metal tri‐tert‐butoxysilanethiolates (Co, 1 ; Cd, 2 ), acetylacetonates (Ni, 3 ; Zn, 4 ), and acetates (Cd, 5 ). All compounds were characterized by single‐crystal X‐ray structure analysis, elemental analysis, FTIR spectroscopy, and thermogravimetry. Complexes 1 , 2 and 4 , 5 exhibit diverse structural conformations: 1 is bimetallic, 2 and 4 are 1D coordination polymers, and 5 is a 2D coordination framework formed from bimetallic units. The obtained complexes contain metal atoms bridged by a molecule of azpy. The luminescent properties of 1–5 were investigated in the solid state.  相似文献   
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