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301.
The aim of the present study was to investigate the phenolic composition and the biological properties of different Aerva lanata (L). Juss. herb extracts obtained with the use of accelerated solvent extraction (ASE), i.e., a green, ecological method, for cosmetic purposes. All samples exhibited high DPPH (9.17–119.85 mg TE/g) and ABTS•+ (9.90–107.58 mg TE/g) scavenging activity. The extracts exhibited considerable anti-lipoxygenase (EC50 between 1.14 mg/mL and 3.73 mg/mL) and anti-xanthine oxidase (EC50 between 1.28 mg/mL and 3.72 mg/mL) activities, moderate chelating activity (EC50 between 1.58 mg/mL and 5.30 mg/mL), and high antioxidant potential in the ORAC assay (0.36–3.84 mM TE/g). Changes in the polyphenol profile of the analysed samples depending on the solvent and temperature used for the extraction were determined with the liquid chromatography/electrospray mass spectrometry (LC-ESI-MS/MS) method. Twenty-one phenolic compounds, including flavonoids and phenolic acids, were detected and quantified. It was shown that tiliroside was one of the main phenolic metabolites in the A. lanata (L.) Juss. herb., which may suggest that this compound may be largely responsible for the observed anti-inflammatory activity of the extracts. In addition, the studied extracts exhibited promising skin-related (anti-tyrosinase, anti-elastase, anti-collagenase, and anti-hyaluronidase) activity. This study showed that Aerva lanata (L.) Juss. contains high amounts of phenolic compounds, including tiliroside, and has good skin-related activities. Therefore, the plant may be interesting as a novel source of bioactive agents for cosmetic industries.  相似文献   
302.
Proteins are ubiquitous macromolecules that display a vast repertoire of chemical and enzymatic functions, making them suitable candidates for chemosignals, used in intraspecific communication. Proteins are present in the skin gland secretions of vertebrates but their identity, and especially, their functions, remain largely unknown. Many lizard species possess femoral glands, i.e., epidermal organs primarily involved in the production and secretion of chemosignals, playing a pivotal role in mate choice and intrasexual communication. The lipophilic fraction of femoral glands has been well studied in lizards. In contrast, proteins have been the focus of only a handful of investigations. Here, we identify and describe inter-individual expression patterns and the functionality of proteins present in femoral glands of male sand lizards (Lacerta agilis) by applying mass spectrometry-based proteomics. Our results show that the total number of proteins varied substantially among individuals. None of the identified femoral gland proteins could be directly linked to chemical communication in lizards, although this result hinges on protein annotation in databases in which squamate semiochemicals are poorly represented. In contrast to our expectations, the proteins consistently expressed across individuals were related to the immune system, antioxidant activity and lipid metabolism as their main functions, showing that proteins in reptilian epidermal glands may have other functions besides chemical communication. Interestingly, we found expression of the Major Histocompatibility Complex (MHC) among the multiple and diverse biological processes enriched in FGs, tentatively supporting a previous hypothesis that MHC was coopted for semiochemical function in sand lizards, specifically in mate recognition. Our study shows that mass spectrometry-based proteomics are a powerful tool for characterizing and deciphering the role of proteins secreted by skin glands in non-model vertebrates.  相似文献   
303.
This study aimed to investigate the possibility of utilizing oat by-products for fiber preparation. Oat husk (OH) and oat bran (OB) were micronized and used to prepare a novel product rich in fiber and with enhanced antioxidant properties. The basic chemical composition and phenolic acid profile were determined in OH and OB. The antioxidant properties of OH and OB were also analyzed. The type and strength of interactions between the biologically active compounds from their mixtures were characterized by an isobolographic analysis. The analyses showed that the sum of phenolic acids was higher in OH than in OB. Ferulic acid was dominant in both OH and OB; however, its content in OH was over sixfold higher than that in OB. The results also suggested that both OH and OB can be used for preparing fiber with enhanced antioxidant properties. The optimal composition of the preparation, with 60–70% of OH and 30–40% of OB, allows for obtaining a product with 60–70% fiber and enhanced antioxidant activity due to bioactive substances and their synergistic effect. The resulting product can be a valuable additive to various food and dietary supplements.  相似文献   
304.
The amino-terminal copper and nickel/N-terminal site (ATCUN/NTS) present in proteins and bioactive peptides exhibits high affinity towards CuII ions and have been implicated in human copper physiology. Little is known, however, about the rate and exact mechanism of formation of such complexes. We used the stopped-flow and microsecond freeze-hyperquenching (MHQ) techniques supported by steady-state spectroscopic and electrochemical data to demonstrate the formation of partially coordinated intermediate CuII complexes formed by glycyl–glycyl–histidine (GGH) peptide, the simplest ATCUN/NTS model. One of these novel intermediates, characterized by two-nitrogen coordination, t1/2≈100 ms at pH 6.0 and the ability to maintain the CuII/CuI redox pair is the best candidate for the long-sought reactive species in extracellular copper transport.  相似文献   
305.
Ordinal pattern statistics for the assessment of heart rate variability   总被引:1,自引:0,他引:1  
The recognition of all main features of a healthy heart rhythm (the so-called sinus rhythm) is still one of the biggest challenges in contemporary cardiology. Recently the interesting physiological phenomenon of heart rate asymmetry has been observed. This phenomenon is related to unbalanced contributions of heart rate decelerations and accelerations to heart rate variability. In this paper we apply methods based on the concept of ordinal pattern to the analysis of electrocardiograms (inter-peak intervals) of healthy subjects in the supine position. This way we observe new regularities of the heart rhythm related to the distribution of ordinal patterns of lengths 3 and 4.  相似文献   
306.
307.
Magnetic properties of nanosize ZnO powders doped with MnO magnetic dopand have been studied. Sample designated as 0.10MnO/0.90ZnO was characterized by XRD that revealed the presence of ZnO and ZnMnO3 phases. An average size of magnetic ZnMnO3 nanocrystallites was 9 nm. Magnetic resonance study has been carried out in the 4-290 K temperature range. The spectrum at each temperature was analyzed in terms of three components. The temperature dependences of resonance field, linewidth and integrated intensity of these components have been determined. Magnetic centers responsible for producing the observed spectra have been proposed.  相似文献   
308.
Journal of Thermal Analysis and Calorimetry - The aim of this study was to obtain carbon foams (CFs) of various pore structure and high mechanical strength using a simple and efficient method to...  相似文献   
309.
Azole. 45.     
The three title compounds, namely (Z)‐1‐(4,5‐di­nitro­imidazol‐1‐yl)‐3‐morpholinopropan‐2‐one 2,4‐di­nitro­phenyl­hydrazone, C16H17N9O9, (IV), (Z)‐3‐morpholino‐1‐(4‐morpholino‐5‐nitro­imidazol‐1‐yl)propan‐2‐one 2,4‐di­nitro­phenyl­hydrazone, C20H25N9O8, (Va), and (E)‐3‐morpholino‐1‐(4‐morpholino‐5‐nitro­imidazol‐1‐yl)propan‐2‐one 2,4‐di­nitro­phenylhydra­zone tetra­hydro­furan solvate, C20H25N9O8·C4H8O, (Vb), have been prepared and their structures determined. In (IV), the C‐4 nitro group is nearly perpendicular to the imidazole ring and the C‐4—NO2 bond length is comparable to the value for a normal single Csp2—NO2 bond. In (IV), (Va) and (Vb), the C‐­5 nitro group deviates insignificantly from the imidazole plane and the C‐5—NO2 bond length is far shorter in all three compounds than C‐4—NO2 in (IV). In consequence, the C‐4 nitro group in (IV) is easily replaced by morpholine, while the C‐5 nitro group in (IV), (Va) and (Vb) shows an extraordinary stability on treatment with the amine. The E configuration in (Vb) is stabilized by a three‐centre hydrogen bond.  相似文献   
310.
This paper attempts to demonstrate empirically the possibility of using a hydrophobic extract of hop cone obtained under the conditions of supercritical carbon dioxide to produce all-purpose cleaner with antimicrobial activity and low irritant potential. A series of prototypes of products varied by the extract concentration was developed. The formulations were assessed for physicochemical properties: particle size, turbidity, and color. The results indicate that the hydrophobic extracts of hop cone can be a valuable component of chemical products intended for washing, having a broad spectrum of action and contributing to improvement of the product’s safety.  相似文献   
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