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991.
Marta Molska Julita Regua Anna Grygier Agata Muzsik-Kazimierska Magdalena Rudziska Anna Gramza-Michaowska 《Molecules (Basel, Switzerland)》2022,27(14)
The aim of the study was to evaluate the effect of the addition of Fagopyrum esculentum Moench buckwheat sprouts modified with the addition of Saccharomyces cerevisiae var. boulardii to an atherogenic diet on the metabolism of sterols and fatty acids in rats. It was noticed in the study that the group fed with modified sprouts (HFDPRS) had a greater amount of sterols by 75.2%, compared to the group fed on an atherogenic diet (HFD). The content of cholesterol in the liver and feces was lower in the HFDPRS group than the HFD group. In the serum of the HFDPRS group, a more significant amount of the following acids was observed: C18:2 (increase by 13.5%), C20:4 (increase by 15.1%), and C22:6 (increase by 13.1%), compared to the HFDCS group. Regarding the biochemical parameters, it was noted that the group fed the diet with the addition of probiotic-rich sprouts diet had lower non-HDL, LDL-C and CRP ratios compared to the group fed the high-fat diet. The obtained results indicate that adding modified buckwheat sprouts to the diet by adding the probiotic strain of the yeast may have a significant impact on the metabolism of the indicated components in the organism. 相似文献
992.
Degradation of organic water pollutants through sonophotocatalysis in the presence of TiO(2) 总被引:5,自引:0,他引:5
The degradation of 2-chlorophenol and of the two azo dyes acid orange 8 and acid red 1 in aqueous solution was investigated kinetically under sonolysis at 20 kHz and under photocatalysis in the presence of titanium dioxide particles, as well as under simultaneous sonolysis and photocatalysis, i.e. sonophotocatalysis. The influence on the degradation and mineralisation rates of the initial substrate concentration and of the photocatalyst amount was systematically investigated to ascertain the origin of the synergistic effect observed between the two degradation techniques. The evolution of hydrogen peroxide during kinetic runs was also monitored. Small amounts of Fe(III) were found to affect both the adsorption equilibria on the semiconductor and the degradation paths. Ultrasound may modify the rate of photocatalytic degradation by promoting the deaggregation of the photocatalyst, by inducing the desorption of organic substrates and degradation intermediates from the photocatalyst surface and, mainly, by favouring the scission of the photocatalytically and sonolytically produced H(2)O(2), with a consequent increase of oxidising species in the aqueous phase. 相似文献
993.
The selective oxidation of styrene under heterogeneous catalyzed conditions delivers environmentally friendly paths for the production of benzaldehyde, an important intermediate for the synthesis of several products. The present review explores heterogeneous catalysts for styrene oxidation using a variety of metal catalysts over the last decade. The use of several classes of supports is discussed, including metal–organic frameworks, zeolites, carbon materials and silicas, among others. The studied catalytic systems propose as most used oxidants tert-butyl hydroperoxide, and hydrogen peroxide and mild reaction conditions. The reaction mechanism proceeds through the generation of an intermediate reactive metal–oxygen species by catalyst-oxidant interactions. Overall, most of the studies highlight the synergetic effects among the metal and support for the activity and selectivity enhancement. 相似文献
994.
The growing climate crisis inspires one of the greatest challenges of the 21st century—developing novel power sources. One of the concepts that offer clean, non-fossil electricity production is fuel cells, especially when the role of fuel is played by simple organic molecules, such as low molecular weight alcohols. The greatest drawback of this technology is the lack of electrocatalytic materials that would enhance reaction kinetics and good stability under process conditions. Currently, electrodes for direct alcohol fuel cells (DAFCs) are mainly based on platinum, which not only provides a poor reaction rate but also readily deactivates because of poisoning by reaction products. Because of these disadvantages, many researchers have focused on developing novel electrode materials with electrocatalytic properties towards the oxidation of simple alcohols, such as methanol, ethanol, ethylene glycol or propanol. This paper presents the development of electrode materials and addresses future challenges that still need to be overcome before direct alcohol fuel cells can be commercialized. 相似文献
995.
Lucia Kovacikova Marta Soltesova Prnova Magdalena Majekova Andrej Bohac Cimen Karasu Milan Stefek 《Molecules (Basel, Switzerland)》2021,26(10)
Aldose reductase (AR, ALR2), the first enzyme of the polyol pathway, is implicated in the pathophysiology of diabetic complications. Aldose reductase inhibitors (ARIs) thus present a promising therapeutic approach to treat a wide array of diabetic complications. Moreover, a therapeutic potential of ARIs in the treatment of chronic inflammation-related pathologies and several genetic metabolic disorders has been recently indicated. Substituted indoles are an interesting group of compounds with a plethora of biological activities. This article reviews a series of indole-based bifunctional aldose reductase inhibitors/antioxidants (ARIs/AOs) developed during recent years. Experimental results obtained in in vitro, ex vivo, and in vivo models of diabetic complications are presented. Structure–activity relationships with respect to carboxymethyl pharmacophore regioisomerization and core scaffold modification are discussed along with the criteria of ‘drug-likeness”. Novel promising structures of putative multifunctional ARIs/AOs are designed. 相似文献
996.
Leite Irena Andrianov Victor Zelencova-Gopejenko Diana Loza Einars Kazhoka-Lapsa Iveta Domracheva Ilona Stoyak Marta Chlopicki Stefan Kalvins Ivars 《Chemistry of Heterocyclic Compounds》2021,57(11):1086-1106
Chemistry of Heterocyclic Compounds - Acyl derivatives of aziridine-2-carboxylic acid have been synthesized and tested as PDIA1 inhibitors. Calculations of charge value and distribution in... 相似文献
997.
Dr. Fabiana E. García Prof. Marta I. Litter Prof. Isabella Natali Sora 《ChemistryOpen》2021,10(8):790-797
The catalytic performance of a perovskite-type lanthanum ferrite LaFeO3 to remove arsenic from water has been investigates for the first time. LaFeO3 was prepared by citrate auto-combustion of dry gel obtained from a solution of the corresponding nitrates poured into citric acid solution. Kinetic studies were performed in the dark with As(V) and in the dark and under UV-C irradiation at pH 6–7 with As(III) (both 1 mg L−1), and As : Fe molar ratios (MR) of 1 : 10 and 1 : 100 using the LaFeO3 catalyst. As(V) was removed from solution after 60 min in the dark in 7 % and in 47 % for MR=1 : 10 and MR=1 : 100, respectively, indicating the importance of the amount of the iron material on the removal. Oxidation of As(III) in the dark was negligible after 60 min in contact with the solid sample, but complete removal of As(III) was observed within 60 min of irradiation at 254 nm, due to As(III) photooxidation to As(V) and to As(III) sorption to a minor extent. Morphological and microstructural studies of the catalyst complement the catalytic testing. This work demonstrates that LaFeO3 can be used for the removal of As(III) from highly arsenic contaminated water. 相似文献
998.
Marta Czarnowska-Kujawska Anna Draszanowska Elbieta Gujska Joanna Klepacka Marta Kasiska 《Molecules (Basel, Switzerland)》2021,26(4)
This study aimed to compare folate contents in hen eggs from four different farming systems, namely organic, free range, barn, and cage one. Folate retention during egg boiling was studied as well. The contents of individual folate vitamers were determined using the high-performance liquid chromatography method (HPLC), following trienzyme treatment. Folate content in eggs differed significantly (p < 0.05) due to the rearing system, with the highest mean content determined in the eggs from organic farming (113.8 µg/100 g). According to this study, one egg (60 g) may provide 40–86 µg of folates, which corresponds to 10–22% of the recommended daily intake for adults, 400 µg according to the Nutrition Standards for the Polish Population. The predominant folate form found in egg was 5-methyltetrahydrofolate, which showed considerably greater stability under boiling compared to 10-formylfolic acid present in a lower amount. In most eggs tested, the losses in total folate content did not exceed 15%. The color of yolk of the most folate-abundant organic eggs, had the highest value of lightness (L*) and the lowest value of redness (a*). This, however, does not correspond to consumer preferences of intense golden yolk color. 相似文献
999.
1000.
Sofia Pessanha Mauro Guerra Stephane Longelin Agnès Le Gac Marta Manso Maria Luisa Carvalho 《X射线光谱测定》2014,43(2):79-82
In this work, the thickness of the gold leaf applied in the Manueline foral charter of Murça (illuminated in 1512) will be determined using X‐ray fluorescence. In the frontispiece of the Manueline foral charter of Murça, the capital D was gilded using a gold leaf over a priming made of lead white. The characteristic lines of Pb (namely Lα and Lβ), although attenuated in the Au layer, are still visible in the X‐ray fluorescence spectra. By determining the intensity ratio Lα/Lβ and comparing it with the ratio for an infinitely thick sample, the thickness of the attenuating material can be determined. Using this methodology, the thickness of the gold leaf applied in the charter of Murça was estimated as 1.6 µm. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献