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61.
《Arabian Journal of Chemistry》2022,15(11):104297
This study aimed to investigate the chemical composition of Tribulus terrestris L. fruit (TT) extract named TT15 and its protective effect against ischemic stroke (IS) as well as corresponding mechanisms. The chemical composition of TT15 was analyzed by liquid chromatography-mass spectrometry (LC-MS), and the compound identification was conducted via searching the in-house database. The LC-MS-based multi-omics approach was applied to search the differential metabolites and differential proteins in rat brain tissue and to explore the biomarker and molecular mechanism of TT15 against middle cerebral artery occlusion (MCAO). A total of 20 compounds were identified from TT15, mainly including alkaloids, flavonoids, phenols, quinones, and esters. These 20 compounds significantly affected the metabolism of 44 metabolites and the expression of 51 proteins. Joint pathway analysis showed that these metabolites and proteins were mainly involved in the response to elevated platelet cytosolic Ca2+ and platelet activation, which inferred that TT15 may exert a protective effect against cerebral ischemic injury via regulating platelet function. This study provides useful information for further exploration of the mechanisms of TT extract against IS. 相似文献
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The present study optimised the ultrasound-assisted extraction (UAE) of bioactive compounds from Amaranthus hypochondriacus var. Nutrisol. Influence of temperature (25.86–54.14 °C) and ultrasonic power densities (UPD) (76.01–273.99 mW/mL) on total betalains (BT), betacyanins (BC), betaxanthins (BX), total polyphenols (TP), antioxidant activity (AA), colour parameters (L*, a*, and b*), amaranthine (A), and isoamaranthine (IA) were evaluated using response surface methodology. Moreover, betalain extraction kinetics and mass transfer coefficients (KLa) were determined for each experimental condition. BT, BC, BX, TP, AA, b*, KLa, and A were significantly affected (p < 0.05) by temperature extraction and UPD, whereas L*, a*, and IA were only affected (p < 0.05) by temperature. All response models were significantly validated with regression coefficients (R2) ranging from 87.46 to 99.29%. BT, A, IA, and KLa in UAE were 1.38, 1.65, 1.50, and 29.93 times higher than determined using conventional extraction, respectively. Optimal UAE conditions were obtained at 41.80 °C and 188.84 mW/mL using the desired function methodology. Under these conditions, the experimental values for BC, BX, BT, TP, AA, L*, a*, b*, KLa, A, and IA were closely related to the predicted values, indicating the suitability of the developed quadratic models. This study proposes a simple and efficient UAE method to obtain betalains and polyphenols with high antioxidant activity, which can be used in several applications within the food industry. 相似文献
66.
《Arabian Journal of Chemistry》2022,15(11):104208
Dendrobium nobile alkaloids (DNLA) and glycosides are the main active components extracted from Dendrobium nobile Lindl. (D. nobile) used for thousands of years in China. The pharmacological effects of the above chemical components are significantly different. D. nobile is mainly grown at an altitude ranging from 230 to 800 m in Chishui City, Northwest Guizhou Province. However, it is unclear whether the metabolite in D. nobile is influenced by the planting altitude. Hence, to reveal the different metabolite in D. nobile cultivated at the altitude of 336 m, 528 m, and 692 m, ultra-high performance liquid chromatography with Q/TOF-MS couple with multivariate analysis were developed. Using the orthogonal partial least squares-discriminant analysis, 19 different metabolites were discovered and then tentatively assigned their structures as alkaloids and glycosides by comparing mass spectrometry data with in-house database and literature. Moreover, the result of semiquantitative analysis showed the content of dendrobine that was belonged to alkaloids significantly increased at the altitude of 692 m, whereas the content of glycosides demonstrated an accumulation trend at the altitude of 528 m. The results could provide valuable information for the optimal clinical drug therapeutics and provide a reference for quality control. 相似文献
67.
The concept of nanoarchitectonics has been proposed as an extensional development of nanotechnology through fusions with material science and the other fields. In nanoarchitectonics, nano-units of atoms, molecules, and nanomaterials are architected into construction of functional material systems. In order to assemble intended structures or hierarchical structures from nano-units, it is more useful to confine nano-units at the interface. In addition, nanoarchitectonics is expected to output functions by harmonizing many units in dynamic environments. However, the liquid interfaces still have lots of unexplored matters in nanoscale because supports by advanced apparatus and techniques in nanotechnology are not always available. Specifically, this review paper summarizes examples of research on molecular manipulation, molecular arrangement and assembly, materials synthesis, and life manipulation at the liquid interface. These examples demonstrate that the liquid interface enables the control of dynamic functions of various size regions, from molecular-level phenomena such as the control of molecular machines to techniques of living creature size such as the control of stem cell differentiation. Liquid interfaces are very useful environments for controlling dynamic functions for a wide range of targets and would have tremendous potential in terms of functional exploration. The great potential of nanoarchitectonics at the liquid interface and the challenges to be solved in the future are also discussed. 相似文献
68.
Sunil K. Ghosh 《Helvetica chimica acta》2023,106(11):e202300141
Acrylates are well known electrophilic alkenes having multitude of applications in organic synthesis. They are very good acceptors in Michael addition reactions and are good enophile/dienophile/dipolarophile partners in cycloaddition reactions. Replacing the β-alkyl/aryl groups in acrylates by a silicon group would be interesting. In addition to the conventional reactions displayed by acrylates, β-silylacrylates (β-SAs) can show reactivity specifically related to the silicon group. Many conventional organic reactions such as hydrodimerization, organocatalytic asymmetric Michael additions, inter- and intra-molecular Diels–Alder reactions, and asymmetric 1,3-dipolar cycloadditions have been used to generate the complex chemical entities from β-SAs. Some of the reaction outcomes were vastly influenced by the silicon substituent. This review describes the practical synthesis β-SAs and their use as starting point in complex molecule generation including total synthesis of some natural products/bioactive molecules. 相似文献
69.
Xiaoliang Lu Jinzhi Zhou Jinxiu Zhao Prof. Dan Wu Xuejing Liu Prof. Xiang Ren Prof. Qin Wei Prof. Huangxian Ju 《Chemphyschem》2023,24(20):e202300536
The electrocatalytic nitrate reduction reaction (NO3−RR) enables the reduction of nitrate to ammonium ions under ambient conditions. It was considered as an alternative reaction for the production of ammonia (NH3) in recent years. In this paper, we report that the Fe doping CoS2 nanoarrays can effectively catalyze the formation of NH3 from nitrate (NO3−) under ambient conditions. This is mainly due to the increase of the NO3− reaction active site by Fe doping and the porous nanostructure of the catalyst, which greatly improves the catalytic activity. Specifically, at −0.9 V vs. RHE, the NH3 yield rate (RNH3) of Fe−CoS2/CC is 17.8×10−2 mmol h−1 cm−2 with Faraday Efficiency (FE) of 88.93 %. Besides, such catalyst shows good durability and catalytic stability, which provides the possibility for the future application of electrocatalytic NH3 production. 相似文献
70.
Vipul Desai Dr. Vinay S. Sharma Suryajit L. Rathod Dr. Anuj S. Sharma Hitendra A. Mali Dr. Rutesh R. Shah Prof. Pranav S. Shrivastav 《Chemphyschem》2023,24(9):e202200803
Four new azo-based supramolecular materials containing thiacalixarene core substituted by variable alkoxy groups ( TFA1 – TFA4 ) have been designed and synthesized for the mesomorphic and photoswitching properties. The liquid crystalline behavior were accomplished by using DSC, POM, and XRD studies. All azo-based thiacalixarene based materials with short and higher chain length display columnar hexagonal mesophase with broad temperature range. The thermal behavior of all the materials was investigated by DSC and TGA study. The structural and conformational study of the lower rim functionalized materials was confirmed by using different techniques. These thiacalixarene moulded liquid crystalline compounds shows columnar self-assembly type behavior and higher thermal stability. The introduction of bi-substituted azo-ester network towards the lower rim of thiacalixarene core has impact on the electron delocalization and liquid crystalline properties. The photoswitching properties suggested cis and trans azo-isomerization under radiation of UV light and higher thermal back relaxation time. The mesogenic behaviour of compound TFA2 and TFA4 were demolished by the influence of cis and trans isomerization. The structure-property correlation is studied to understand the variation in mesogenic properties with the substitution of variable alkoxy side chain. 相似文献