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21.
Min Yang Chih-Yao Hou Hsien-Yi Hsu Sulfath Hakkim Hazeena Shella Permatasari Santoso Cheng-Chia Yu Chao-Kai Chang Mohsen Gavahian Chang-Wei Hsieh 《Molecules (Basel, Switzerland)》2022,27(23)
Pickled radish (Raphanus sativus) is a traditional Asian ingredient, but the traditional method takes decades to make this product. To optimize such a process, this study compared the saponin content of pickled radishes with different thermal processing and traditional processes (production time of 7 days, 10 years, and 20 years) and evaluated the effects of different thermal processes on the formation of radish saponin through kinetics study and mass spectrometry. The results showed that increasing the pickling time enhanced the formation of saponin in commercial pickled radishes (25 °C, 7 days, 6.50 ± 1.46 mg g−1; 3650 days, 23.11 ± 1.22 mg g−1), but these increases were lower than those induced by thermal processing (70 °C 30 days 24.24 ± 1.01 mg g−1). However, it was found that the pickling time of more than 10 years and the processing temperature of more than 80 °C reduce the saponin content. Liquid chromatography–mass spectrometry (LC-MS) analysis showed that the major saponin in untreated radish was Tupistroside G, whereas treated samples contained Asparagoside A and Timosaponin A1. Moreover, this study elucidated the chemical structure of saponins in TPR. The findings indicated that thermal treatment could induce functional saponin conversion in plants, and such a mechanism can also be used to improve the health efficacy of plant-based crops. 相似文献
22.
Noha M. Soliman Faiyaz Shakeel Nazrul Haq Fars K. Alanazi Sultan Alshehri Mohsen Bayomi Ahmed S. M. Alenazi Ibrahim A. Alsarra 《Molecules (Basel, Switzerland)》2022,27(14)
Various chitosan (CS)-based nanoparticles (CS-NPs) of ciprofloxacin hydrochloride (CHCl) have been investigated for therapeutic delivery and to enhance antimicrobial efficacy. However, the Box–Behnken design (BBD)-supported statistical optimization of NPs of CHCl has not been performed in the literature. As a result, the goal of this study was to look into the key interactions and quadratic impacts of formulation variables on the performance of CHCl-CS-NPs in a systematic way. To optimize CHCl-loaded CS-NPs generated by the ionic gelation process, the response surface methodology (RSM) was used. The BBD was used with three factors on three levels and three replicas at the central point. Tripolyphosphate, CS concentrations, and ultrasonication energy were chosen as independent variables after preliminary screening. Particle size (PS), polydispersity index (PDI), zeta potential (ZP), encapsulation efficiency (EE), and in vitro release were the dependent factors (responses). Prepared NPs were found in the PS range of 198–304 nm with a ZP of 27–42 mV. EE and drug release were in the range of 23–45% and 36–61%, respectively. All of the responses were optimized at the same time using a desirability function based on Design Expert® modeling and a desirability factor of 95%. The minimum inhibitory concentration (MIC) of the improved formula against two bacterial strains, Pseudomonas aeruginosa and Staphylococcus aureus, was determined. The MIC of the optimized NPs was found to be decreased 4-fold compared with pure CHCl. The predicted and observed values for the optimized formulation were nearly identical. The BBD aided in a better understanding of the intrinsic relationship between formulation variables and responses, as well as the optimization of CHCl-loaded CS-NPs in a time- and labor-efficient manner. 相似文献
23.
Hooman Moradpour Mohsen Javaherian Ebrahim Namvar Amir Hadi Ziaie 《Entropy (Basel, Switzerland)》2022,24(6)
Relying on the quantum tunnelling concept and Maxwell–Boltzmann–Gibbs statistics, Gamow shows that the star-burning process happens at temperatures comparable to a critical value, called the Gamow temperature () and less than the prediction of the classical framework. In order to highlight the role of the equipartition theorem in the Gamow argument, a thermal length scale is defined, and then the effects of non-extensivity on the Gamow temperature have been investigated by focusing on the Tsallis and Kaniadakis statistics. The results attest that while the Gamow temperature decreases in the framework of Kaniadakis statistics, it can be bigger or smaller than when Tsallis statistics are employed. 相似文献
24.
Malekahmadi Omid Kalantar Mahdi Nouri-Khezrabad Mohsen 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2109-2126
Journal of Thermal Analysis and Calorimetry - The hydroxyapatite is one of the biocompatible and insulating bioceramics, while the carbon nanotube has a high thermal conductivity potential. This... 相似文献
25.
Optical Review - Importance of simultaneous measurement of temperature and strain by fiber Bragg grating (FBG) sensors has led to innovation of several renewing techniques. Most of them are based... 相似文献
26.
One‐pot synthesis of 1‐ and 5‐substituted 1H‐tetrazoles using 1,4‐dihydroxyanthraquinone–copper(II) supported on superparamagnetic Fe3O4@SiO2 magnetic porous nanospheres as a recyclable catalyst 下载免费PDF全文
An effective one‐pot, convenient process for the synthesis of 1‐ and 5‐substituted 1H‐tetrazoles from nitriles and amines is described using1,4‐dihydroxyanthraquinone–copper(II) supported on Fe3O4@SiO2 magnetic porous nanospheres as a novel recyclable catalyst. The application of this catalyst allows the synthesis of a variety of tetrazoles in good to excellent yields. The preparation of the magnetic nanocatalyst with core–shell structure is presented by using nano‐Fe3O4 as the core, tetraethoxysilane as the silica source and poly(vinyl alcohol) as the surfactant, and then Fe3O4@SiO2 was coated with 1,4‐dihydroxyanthraquinone–copper(II) nanoparticles. The new catalyst was characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, field emission scanning electron microscopy, dynamic light scattering, thermogravimetric analysis, vibration sample magnetometry, X‐ray photoelectron spectroscopy, nitrogen adsorption–desorption isotherm analysis and inductively coupled plasma analysis. This new procedure offers several advantages such as short reaction times, excellent yields, operational simplicity, practicability and applicability to various substrates and absence of any tedious workup or purification. In addition, the excellent catalytic performance, thermal stability and separation of the catalyst make it a good heterogeneous system and a useful alternative to other heterogeneous catalysts. Also, the catalyst could be magnetically separated and reused six times without significant loss of catalytic activity. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
27.
Dendrimer‐encapsulated Cu(Π) nanoparticles immobilized on superparamagnetic Fe3O4@SiO2 nanoparticles as a novel recyclable catalyst for N‐arylation of nitrogen heterocycles and green synthesis of 5‐substituted 1H‐tetrazoles 下载免费PDF全文
In this study, dendrimer‐encapsulated Cu(Π) nanoparticles immobilized on superparamagnetic Fe3O4@SiO2 nanoparticles were prepared via a multistep‐synthesis. Then, the synthesized composite was fully characterized by various techniques such as fourier transform infrared (FT‐IR) spectroscopy, X‐ray diffraction (XRD), dynamic light scattering (DLS), UV‐vis spectroscopy, energy dispersive X‐ray analysis (EDX), thermogravimetric analysis (TGA) and vibration sample magnetometer (VSM). From the information gained by FE‐SEM and TEM studies it can be inferred that the particles are mostly spherical in shape and have an average size of 50 nm. Also, the amount of Cu is determined to be 0.51 mmol/g in the catalyst by inductively coupled plasma (ICP) analyzer. This magnetic nano‐compound has been successfully applied as a highly efficient, magnetically recoverable and stable catalyst for N‐arylation of nitrogen heterocycles with aryl halides (I, Br) and arylboronic acids without using external ligands or additives. The catalyst was also employed in a one‐pot, three‐component reaction for the efficient and green synthesis of 5‐substituted 1H‐tetrazoles using various aldehydes, hydroxylamine hydrochloride and sodium azide in water. The magnetic catalyst can be easily separated by an external magnet bar and is recycled seven times without significant loss of its activity. 相似文献
28.
Research on Chemical Intermediates - Calcined oyster shell nanoparticles (COS NPs) as a novel heterogeneous nanocatalyst were prepared and fully characterized by X-ray fluorescence analysis,... 相似文献
29.
30.
M. Mirza-Aghayan N. Mohammadian M. Abolghasemi Malakshah R. Boukherroub A. A. Tarlani 《Journal of the Iranian Chemical Society》2013,10(3):559-563
A simple and efficient approach towards one-step synthesis of 2-amino-5-cyano-4-hydroxy-6-aryl pyrimidines has been developed. It is based on three-component condensation of aliphatic, aromatic or heterocyclic aldehydes, ethyl cyanoacetate and guanidinium carbonate in the presence of amino-functionalized SBA-15 catalyst in ethanol. In this chemical process, the tautomeric interconversion of pyrimidine derivatives has been observed. This efficient technique has the advantage to give 2-amino-pyrimidine derivatives using a heterogeneous catalyst in high yields, to be completed in short reaction times and to offer a simple product isolation procedure. 相似文献