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51.
Geetika Wadhwa Kowthavarapu Venkata Krishna Rajeev Taliyan Neeraj Tandon Satyapal Singh Yadav Dipankar Banerjee Avinash Narwaria Chandrakant Katiyar Sunil Kumar Dubey 《Biomedical chromatography : BMC》2022,36(2):e5275
Trigonelline (TR), 4-hydroxyisoleucine (4-HI), and diosgenin (DG) are the main bioactives of the purified standardized extract of the popular plant Trigonella foenum-graecum L. (TFG), and it has been proven effective for the treatment of various diseases. However, to the best of our knowledge, no study has investigated the pharmacokinetic parameters of purified standardized T. foenum-graecum extract in normal and diabetic Wistar rats. The present study has developed and validated a rapid, reliable, and sensitive simultaneous ultra-performance liquid chromatography MS method to estimate these bioactives. The chromatographic separation was achieved using methanol, acetonitrile, and 0.1% formic acid with the ideal gradient flow system on a BEH Shield RP 18 column. A positive electrospray ionization mode was selected to estimate m/z values of TR (138.14 > 94.63), 4-HI (148.19 > 74.08), and DG (415.54 > 271.33). The method was robust and reproducible over the linearity range of 60–5000, 6–5000, and 15–5000 ng/mL for TR, 4-HI, and DG, respectively. Using this novel validated method, we investigated the pharmacokinetic parameters of bioactives using Phoenix WinNonlin version 8.0 (Certera) in normal and diabetic rats. The assay was successfully applied for the estimation of pharmacokinetic parameters using noncompartmental analysis. This investigation shows that the absorption rate increased, whereas distribution and elimination processes slowed down in diabetic rats compared with normal rats. 相似文献
52.
Aradhya Dev Srivastav Vireshwar Singh Deepak Singh Sunita Singh Suresh Kumar Patel Dilip Kumar Sudeep Yadav Balendu Shekher Giri Dhananjay Singh 《印度化学会志》2022,99(8):100632
Nelumbo nucifera leaves are rich source of natural wax possessing super-hydrophobic properties. It provides protection to them from ecological turbulences and climatic wear and tear. In this study, various experiments have been conducted to observe the yield of extraction and the determination of various functional groups, which are present in natural wax, derived from Nelumbo nucifera leaves. The natural wax has been extracted from lotus leaves through non-polar (hexane) and polar (ethanol) solvent via different extraction methods. The superhydrophobic wax has been successfully extracted with hexane. Whereas, ethanol did not extract the water-repellent wax of lotus leaf. Considering the cumulative amount, i.e. (desired + undesired), the maceration shows the extraction of 2.9% (%w/w, through hexane) and 10.2% (%w/w, through ethanol), while it was found 2.5% (%w/w, cycle period 15 min) and 9.0% (%w/w, cycle period 26 min) respectively, in case of Soxhlet extraction technique. For this specific case of natural wax recovery from biomass (lotus leaf), the maceration (traditional method) resulted a little bit superior extraction yield in comparison to the Soxhlet extraction method for extraction of crude wax. In the case of non-polar solvent (hexane), an extraction yield of 1.97% (%w/w) through maceration method was observed while in the case of non-polar solvent (ethanol), an extraction yield of 1.62% (%w/w) through Soxhlet extraction was observed. The TLC analysis on both types of extracts was performed. For the detection of various hydrocarbon chains in the crude wax extracts, FTIR was also performed. Topography of wax surface and wax-coated waterproof fabric was compared through SEM. 相似文献
53.
Jyoti S. Gokhale Moreshwar P. Hude Ganapati D. Yadav Morgan Thomas Janusz Kozinski Ajay K. Dalai 《印度化学会志》2022,99(9):100647
An ongoing major outbreak of mountain pine beetle in Western Canada has provided a clear opportunity to utilize waste pinewood as a source of renewable energy. Therefore hydrothermal processing of waste pinewood as a feedstock for bio-oil and biochar production using subcritical and supercritical water technology was carried out in semi-batch mode to investigate the effect of pressure (200–400 bar) and temperature (300–400 °C) on the yield and composition of bio-oil. The pinewood samples have very high cellulose and hemicellulose content but low ash content and are thus a formidable feedstock for bioenergy production. The optimum conditions for the hydrothermal processing of the pinewood in a tubular reactor were found to be 400 °C and 250 bars with respect to biochar and bio-oil yield based on the highest calorific value analysis. Detailed characterization of bio-oil and biochar was performed using GCMS, NMR, SEM, calorific value, and elemental analysis, respectively. The critical components of bio-oil were found to be phenols, methoxyphenols, hydroxymethyl furfural (HMF), and vanillin, whereas as compared to the raw pine wood, the biochar was considerably lower H:C and O:C ratios than those of the unprocessed pinewood. The analyses of bio-oil by means of GCMS and 1H NMR showed that it was mainly composed of heterocyclic compounds, phenols, aldehydes and acids. 相似文献
54.
Lakhera Shradha Rana Meenakshi Devlal Kamal Celik Ismail Yadav Rohitash 《Structural chemistry》2022,33(3):703-719
Structural Chemistry - Tridax procumbens is a flowering plant of the Asteraceae family with a wide range of medicinal uses like anti-inflammatory, anti-diabetic, anti-microbial, immunomodulatory,... 相似文献
55.
Bedadyuti Vedvyas Pati Asit Ghosh Komal Yadav Shyam Kumar Banjare Shalini Pandey Upakarasamy Lourderaj Ponneri C. Ravikumar 《Chemical science》2022,13(9):2692
The stereoselective synthesis of 1,3-enynes from 1,3-diynes is demonstrated by palladium-catalyzed selective C–C bond cleavage of cyclopropanol. Exclusive formation of mono-alkenylated adducts was achieved by eliminating the possibility of di-functionalization with high stereoselectivity. Indeed, this protocol worked very well with electronically and sterically diverse substrates. Several studies, including deuterium labeling experiments and intermolecular competitive experiments, were carried out to understand the mechanistic details. The atomic-level mechanism followed in the catalytic process was also validated using DFT calculations, and the rate-controlling states in the catalytic cycle were identified. Furthermore, preliminary mechanistic investigations with radical scavengers revealed the non-involvement of the radical pathway in this transformation.Palladium-catalyzed tandem activation and functionalization of readily accessible cyclopropanols have been demonstrated to access valuable conjugated enynes from 1,3-diynes with high stereo-selectivity. 相似文献
56.
GVSRPavan Kumar KSrinivasa Rao Arunendra Yadav MLakshman Kumar HSainadh Dora 《印度化学会志》2022,99(5):100338
Groundwater quality is the major concern all over the world. Natural processes and manmade activities are the prime reasons for the contamination of available water resources. It is crucial to assess the quality of groundwater in areas surrounded by various industries. The present study was carried out to assess the groundwater quality during pre-monsoon and post monsoon seasons of 2016, in two mandals of Vizianagaram district of Andhra Pradesh via multivariate statistical analysis and water quality index method. The present work gains importance in light of the construction of proposed international airport at Bhohapuram and the existence of various industries in Pusapatirega mandal. A total of thirty-seven villages, eighteen from Bhogapuram mandal and seventeen from Pusapatirega mandal were selected for the present study. Factor analysis, linear regression analysis, correlation matrix analysis and cluster analysis tools were used to emphasize the parameters influencing quality of water in the chosen study area. From the analysis reports, it was found that the groundwater of the two mandals under investigation was strongly influenced by EC, TDS, total hardness(TH), Ca+2, Mg+2 and K+. During the two seasons under study, the water quality index value was found to be greater than 100 indicating that the water is unfit for human consumption. Concentration of Ca+2, Mg+2 and K+ were found to be beyond the permissible limits prescribed by BIS (2012). Dissolution of calcium and magnesium bearing minerals, mixing of industrial and household wastes may be the reasons for elevated concentration levels of these parameters. 相似文献
57.
Dr. Ravi Yadav Martin Weber Dr. Akhil K. Singh Luca Münzfeld Johannes Gramüller Prof. Dr. Ruth M. Gschwind Prof. Dr. Manfred Scheer Prof. Dr. Peter W. Roesky 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(56):14128-14137
A series of molecular group 2 polyphosphides has been synthesized by using air-stable [Cp*Fe(η5-P5)] (Cp*=C5Me5) or white phosphorus as polyphosphorus precursors. Different types of group 2 reagents such as organo-magnesium, mono-valent magnesium, and molecular calcium hydride complexes have been investigated to activate these polyphosphorus sources. The organo-magnesium complex [(DippBDI−Mg(CH3))2] (DippBDI={[2,6-iPr2C6H3NCMe]2CH}−) reacts with [Cp*Fe(η5-P5)] to give an unprecedented Mg/Fe-supramolecular wheel. Kinetically controlled activation of [Cp*Fe(η5-P5)] by different mono-valent magnesium complexes allowed the isolation of Mg-coordinated formally mono- and di-reduced products of [Cp*Fe(η5-P5)]. To obtain the first examples of molecular calcium-polyphosphides, a molecular calcium hydride complex was used to reduce the aromatic cyclo-P5 ring of [Cp*Fe(η5-P5)]. The Ca-Fe-polyphosphide is also characterized by quantum chemical calculations and compared with the corresponding Mg complex. Moreover, a calcium coordinated Zintl ion (P7)3− was obtained by molecular calcium hydride mediated P4 reduction. 相似文献
58.
Dan Yuan Sharda Yadav Hang T. Ta Hedieh Fallahi Hongjie An Navid Kashaninejad Chin Hong Ooi Nam-Trung Nguyen Jun Zhang 《Electrophoresis》2021,42(21-22):2230-2237
Microfluidic particle focusing has been a vital prerequisite step in sample preparation for downstream particle separation, counting, detection, or analysis, and has attracted broad applications in biomedical and chemical areas. Besides all the active and passive focusing methods in Newtonian fluids, particle focusing in viscoelastic fluids has been attracting increasing interest because of its advantages induced by intrinsic fluid property. However, to achieve a well-defined focusing position, there is a need to extend channel lengths when focusing micrometer-sized or sub-microsized particles, which would result in the size increase of the microfluidic devices. This work investigated the sheathless viscoelastic focusing of particles and cells in a zigzag microfluidic channel. Benefit from the zigzag structure of the channel, the channel length and the footprint of the device can be reduced without sacrificing the focusing performance. In this work, the viscoelastic focusing, including the focusing of 10 μm polystyrene particles, 5 μm polystyrene particles, 5 μm magnetic particles, white blood cells (WBCs), red blood cells (RBCs), and cancer cells, were all demonstrated. Moreover, magnetophoretic separation of magnetic and nonmagnetic particles after viscoelastic pre-focusing was shown. This focusing technique has the potential to be used in a range of biomedical applications. 相似文献
59.
Dr. Papri Sutar Dr. Vasudeva Rao Bakuru Pooja Yadav Subhajit Laha Dr. Suresh Babu Kalidindi Prof. Dr. Tapas Kumar Maji 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(10):3268-3272
The composite hydrogel of a nanoscale metal–organic framework (NMOF) and nanoclay has emerged as a new soft-material with advanced properties and applications. Herein, we report a facile synthesis of a hydrogel nanocomposite by charge-assisted self-assembly of Pd@ZIF-8 nanoparticles with Laponite® nanoclay which coat the surface of Pd@ZIF-8 nanoparticles. Such surface coating significantly enhanced the thermal stability of the ZIF-8 compared to the pristine framework. Further, the Pd@ZIF-8+LP hydrogel nanocomposite shows better size-selective catalytic hydrogenation of olefins than Pd@ZIF-8 nanoparticles based on selective diffusion of the substrate. 相似文献
60.
Dr. Bhupendra Goswami Dr. Thomas J. Feuerstein Dr. Ravi Yadav Dr. Ralf Köppe Dr. Sergei Lebedkin Prof. Dr. Manfred M. Kappes Prof. Dr. Peter W. Roesky 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(13):4401-4411
The synthesis of calcium complexes ligated by three different chiral iminophosphonamide ligands, L- H ( L =[Ph2P{N(R)CH(CH3)Ph}2]), L′ -H ( L′ =[Ph2P{NDipp}{N(R)CH(CH3)Ph}]), (Dipp=2,6-iPr2C6H3), and L′′ -H ( L′′ =[Ph2P{N(R)CH(CH3)naph}2]), (naph=naphthyl) is presented. The resulting structures [ L 2Ca], [ L′ 2Ca], and [ L′′ 2Ca] represent the first examples of enantiopure homoleptic calcium complexes based on this type of ligands. The calcium complexes show blue–green photoluminescence (PL) in the solid state, which is especially bright at low temperatures. Whereas the emission of [ L′′ 2Ca] is assigned to the fluorescence of naphthyl groups, the PL of [ L 2Ca] and [ L′ 2Ca] is contributed by long-lived phosphorescence and thermally activated delayed fluorescence (TADF), with a strong variation of the PL lifetimes over the temperature range of 5–295 K. Furthermore, an excellent catalytic activity was found for these complexes in hydroboration of ketones at room temperature, although no enantioselectivity was achieved. 相似文献