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961.
Umair Khurshid Saeed Ahmad Hammad Saleem Arslan Hussain LodhI Irfan Pervaiz Mohsin Abbas Khan Haroon Khan Abdulwahab AlamrI Mukhtar AnsarI Marcello LocatellI Muhammad Adeel Arshad Muhammad Asif Wazir Juwairiya Butt Sirajudheen Anwar 《Molecules (Basel, Switzerland)》2022,27(18)
This work was undertaken to explore the phytochemical composition, antioxidant, and enzyme-inhibiting properties of Neurada procumbens L. extracts/fractions of varying polarity (methanol extract and its fractions including n-hexane, chloroform, n-butanol, and aqueous fractions). A preliminary phytochemical study of all extracts/fractions, HPLC-PDA polyphenolic quantification, and GC-MS analysis of the n-hexane fraction were used to identify the phytochemical makeup. Antioxidant (DPPH), enzyme inhibition (against xanthine oxidase, carbonic anhydrase, and urease enzymes), and antibacterial activities against seven bacterial strains were performed for biological investigation. The GC-MS analysis revealed the tentative identification of 22 distinct phytochemicals in the n-hexane fraction, the majority of which belonged to the phenol, flavonoid, sesquiterpenoid, terpene, fatty acid, sterol, and triterpenoid classes of secondary metabolites. HPLC-PDA analysis quantified syringic acid, 3-OH benzoic acid, t-ferullic acid, naringin, and epicatechin in a significant amount. All of the studied extracts/fractions displayed significant antioxidant capability, with methanol extract exhibiting the highest radical-scavenging activity, as measured by an inhibitory percentage of 81.4 ± 0.7 and an IC50 value of 1.3 ± 0.3. For enzyme inhibition experiments, the n-hexane fraction was shown to be highly potent against xanthine oxidase and urease enzymes, with respective IC50 values of 2.3 ± 0.5 and 1.1 ± 0.4 mg/mL. Similarly, the methanol extract demonstrated the strongest activity against the carbonic anhydrase enzyme, with an IC50 value of 2.2 ± 0.4 mg/mL. Moreover, all the studied extracts/fractions presented moderate antibacterial potential against seven bacterial strains. Molecular docking of the five molecules β-amyrin, campesterol, ergosta-4,6,22-trien-3β-ol, stigmasterol, and caryophyllene revealed the interaction of these ligands with the investigated enzyme (xanthine oxidase). The results of the present study suggested that the N. procumbens plant may be evaluated as a possible source of bioactive compounds with multifunctional therapeutic applications. 相似文献
962.
Muhammad Asim Akbar Hussain Safia Khan Javeria Arshad Tehmeena Maryum Butt Amina Hana Mehwish Munawar Farhat Saira Malika Rani Arshad Mahmood Naveed Kausar Janjua 《Molecules (Basel, Switzerland)》2022,27(18)
Hexanary high-entropy oxides (HEOs) were synthesized through the mechanochemical sol-gel method for electrocatalytic water oxidation reaction (WOR). As-synthesized catalysts were subjected to characterization, including X-ray diffraction (XRD), Fourier transforms infrared (FTIR) analysis, and scanning electron microscopy (SEM). All the oxide systems exhibited sharp diffraction peaks in XRD patterns indicating the defined crystal structure. Strong absorption between 400–700 cm−1 in FTIR indicated the formation of metal-oxide bonds in all HEO systems. WOR was investigated via cyclic voltammetry using HEOs as electrode platforms, 1M KOH as the basic medium, and 1M methanol (CH3OH) as the facilitator. Voltammetric profiles for both equiatomic (EHEOs) and non-equiatomic (NEHEOs) were investigated, and NEHEOs exhibited the maximum current output for WOR. Moreover, methanol addition improved the current profiles, thus leading to the electrode utility in direct methanol fuel cells as a sequential increase in methanol concentration from 1M to 2M enhanced the OER current density from 61.4 to 94.3 mA cm−2 using NEHEO. The NEHEOs comprising a greater percentage of Al, ([Al0.35(Mg, Fe, Cu, Ni, Co)0.65]3O4) displayed high WOR catalytic performance with the maximum diffusion coefficient, D° (10.90 cm2 s−1) and heterogeneous rate constant, k° (7.98 cm s−1) values. These primary findings from the EC processes for WOR provide the foundation for their applications in high-energy devices. Conclusively, HEOs are proven as novel and efficient catalytic platforms for electrochemical water oxidation. 相似文献
963.
Rafaqat Hussain Hayat Ullah Fazal Rahim Maliha Sarfraz Muhammad Taha Rashid Iqbal Wajid Rehman Shoaib Khan Syed Adnan Ali Shah Sajjad Hyder Majid Alhomrani Abdulhakeem S. Alamri Osama Abdulaziz Mahmoud A. Abdelaziz 《Molecules (Basel, Switzerland)》2022,27(18)
Twenty-four analogues of benzimidazole-based thiazoles (1–24) were synthesized and assessed for their in vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory potential. All analogues were found to exhibit good inhibitory potential against cholinesterase enzymes, having IC50 values in the ranges of 0.10 ± 0.05 to 11.10 ± 0.30 µM (for AChE) and 0.20 ± 0.050 µM to 14.20 ± 0.10 µM (for BuChE) as compared to the standard drug Donepezil (IC50 = 2.16 ± 0.12 and 4.5 ± 0.11 µM, respectively). Among the series, analogues 16 and 21 were found to be the most potent inhibitors of AChE and BuChE enzymes. The number (s), types, electron-donating or -withdrawing effects and position of the substituent(s) on the both phenyl rings B & C were the primary determinants of the structure-activity relationship (SAR). In order to understand how the most active derivatives interact with the amino acids in the active site of the enzyme, molecular docking studies were conducted. The results obtained supported the experimental data. Additionally, the structures of all newly synthesized compounds were elucidated by using several spectroscopic methods like 13C-NMR, 1H-NMR and HR EIMS. 相似文献
964.
Muhammad Abdullah Shah Ala Uddin Muhammad Raza Shah Imdad Ali Riaz Ullah Peer Abdul Hannan Hidayat Hussain 《Molecules (Basel, Switzerland)》2022,27(19)
Hydrazones are active compounds having an azomethine –NHN=CH group and are widely studied owing to their ease of preparation and diverse pharmacological benefits. Novel isonicotinic hydrazone derivatives of vanillin aldehyde and salicyl aldehyde were synthesized that had azomethine linkages and were characterized by UV–Visible, FTIR, EI-MS, 1H-NMR and 13C-NMR spectroscopy. The compounds were screened for their antibacterial activity against Staphylococcus aureus, Bacillus subtilus, and Escherichia coli using disc diffusion and minimum inhibitory concentration (MIC) methods. For cytotoxicity, a brine shrimp lethality test was performed to calculate the lethal concentration (LC50). The results demonstrated appreciable antibacterial activities against the applied strains, amongst which the compounds coded NH3 and NH5 showed maximum inhibition and MIC responses. In terms of cytotoxic activity, the maximum effect was observed in compound NH5 and NH6 treatments with minimum survival percentages of 36.10 ± 3.45 and 32.44 ± 2.0, respectively. These hydrazones could be potential candidates in antitumorigenic therapy against various human cancer cells. 相似文献
965.
Shoaib Khan Shahid Iqbal Fazal Rahim Mazloom Shah Rafaqat Hussain Hamad Alrbyawi Wajid Rehman Ayed A. Dera Liaqat Rasheed H. H. Somaily Rami Adel Pashameah Eman Alzahrani Abd-ElAziem Farouk 《Molecules (Basel, Switzerland)》2022,27(19)
Amylase and glucosidase enzymes are the primary harmful source in the development of the chronic condition known as diabetes mellitus. The main function of these enzymes is to break the macromolecules into simple sugar units which are directly involved in the solubility of blood, hence increasing blood glucose levels. To overcome this effect, there is a need for a potent and effective inhibitor that inhibits the conversion of macromolecules of sugar into its smaller units. In this regard, we synthesized thiazolidinone-based indole derivatives (1–20). The synthesized derivatives were evaluated for α-amylase and α-glucosidase inhibitory activity. Different substituted derivatives were found with moderate to good potentials having IC50 values ranging, for α-amylase, from 1.50 ± 0.05 to 29.60 ± 0.40 μM and, for α-glucosidase, from IC50 = 2.40 ± 0.10 to 31.50 ± 0.50 μM. Among the varied substituted compounds, the most active analogs four (1.80 ± 0.70 and 2.70 ± 0.70), five (1.50 ± 0.05 and 2.40 ± 0.10, respectively) of the series showed few folds better inhibitory activity than standard drug acarbose (IC50 = 10.20 ± 0.10 and 11.70 ± 0.10 μM, respectively). Moreover, structure–activity relationship (SAR) was established and binding interactions were analyzed for ligands and proteins (α-amylase and α-glucosidase) through a molecular docking study. 相似文献
966.
This work suggests a new model for anisotropic compact stars with quintessence in f(T)gravity by us-ing the off-diagonal tetrad and the power-law as f(T)=βTn,where T is the scalar torsion andβand n are real con-stants.The acquired field equations incorporating the anisotropic matter source along with the quintessence field,in f(T)gravity,are investigated by making use of the specific character of the scalar torsion T for the observed stars PSRJ1614-2230,4U1608-52.CenX-3,EXO1785-248,and SMCX-1.It is suggested that all the stellar struc-tures under examination are advantageously independent of any central singularity and are stable.Comprehensive graphical analysis shows that various physical features which are crucially important for the emergence of the stellar structures are conferred. 相似文献
967.
cis‐Cobalt complexes with salicycaldoxime(SAO), (Z)‐1‐(2‐hydroxyphenyl)ethanonoxime (HEO), (Z)‐1‐(2,5‐dihydroxyphenyl)ethanonoxime (DEO), (Z)‐1‐(2,5‐dihydroxyphenyl)(phenyl)methanonoxime (DPO) and their adducts with pyridine (Py) and imidazole (Im) were synthesized and characterized by elemental analysis, magnetic susceptibility, UV‐Vis and IR spectra. The electrochemical studies were carried by cyclic voltammeter, the peak potential separation and formal potential of complexes were independent of sweep rate or scan rate (ν) indicating a quasi reversible one‐electron redox process. Absorption studies and thermal denature studies revealed that each of these octahedral complexes is an avid binder of calf thymus DNA. The apparent binding constants for mixed ligand complexes are in order of ~103‐103 M?1. Based on the data obtained in the DNA binding studies a partial intercalative mode of binding is suggested for these complexes. The nucleolytic cleavage activity of parent complexes and their pyridine adduct were carried out on double stranded pBR322 circular plasmid DNA by using a gel electrophoresis experiment in the presence and absence of oxidant (H2O2). All the metal complexes show enhanced cleavage activity in presence of oxidant. The hydrolytic cleavage of DNA of Co(DEO)2 and Co(DPO)2 is evidenced from the control experiments showing discernable cleavage inhibition in the presence of the hydroxyl radical inhibitor DMSO and EDTA. 相似文献
968.
Development of erbium phosphate doped poly(glycidyl methacrylate/ethylene dimethacrylate) spin columns for selective enrichment of phosphopeptides
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Yüksel Güzel Matthias Rainer Christoph B. Messner Shah Hussain Florian Meischl Michael Sasse Richard Tessadri Günther K. Bonn 《Journal of separation science》2015,38(8):1334-1343
In this study, a novel method for the highly selective enrichment of phosphopeptides using erbium phosphate doped poly(glycidyl methacrylate/ethylene dimethacrylate) spin columns is presented. Erbium phosphate was synthesized by precipitation from boiling phosphoric acid and incubated overnight in erbium chloride solutions. The resulting powder was embedded in a monolithic poly(glycidyl methacrylate/ethylene dimethacrylate) polymer. The monolith was synthesized in a spin column by radical polymerization. Erbium phosphate demonstrated a high affinity and selectivity for phosphopeptides due to the strong interaction of trivalent erbium ions with the phosphate groups of phosphopeptides. The high selectivity and performance of the designed spin columns were demonstrated by successfully enriching phosphopeptides from tryptically digested protein mixtures containing the model phosphoproteins α‐ and β‐casein, bovine milk, and human saliva. By the implementation of several washing steps, unspecific components were removed and the enriched phosphopeptides were effectively eluted from the spin columns under alkaline conditions. The selective performance of the presented method was further demonstrated by the enrichment of two synthetic phosphopeptides, which were spiked in tryptically digested and dephosphorylated HeLa cell lysates at low ratios. Finally, the presented approach was compared to conventional phosphopeptide enrichment by titanium oxide and revealed higher recoveries for the erbium phosphate doped monoliths. 相似文献
969.
用一步合成自组装法制备出了氢氧化钴与还原氧化石墨烯(Co(OH)2/rGO)的复合催化剂,并将其用于水中染料的催化降解实验.通过X射线衍射(XRD),激光拉曼(Raman)光谱,透射电镜(TEM),X射线能量色散谱(EDS)以及X射线光电子能谱(XPS)等一系列分析手段对催化剂的结构形貌进行了详细的表征,表征结果证实氢氧化钴很好地附着在还原石墨烯的表面.最后初步考察了催化剂催化单过硫酸钾(PMS)降解酸性橙(AO7)的性能.结果表明,催化剂显示出了高效的催化性能,酸性橙的色度可在12 min内完全去除,总有机碳(TOC)实验也表明染料降解的同时也可获得较高的矿化度.循环稳定性实验表明在进行到第三次实验时,催化剂仍能保持高的催化活性,将酸性橙在16 min内降解完毕. 相似文献
970.
Enhanced preconcentration of selected chlorofluorocarbons on multiwalled carbon nanotubes with polar functionalities
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Chutarat Saridara Chaudhery Mustansar Hussain Smruti Ragunath Somenath Mitra 《Journal of separation science》2015,38(3):426-432
Chromatographic monitoring of chlorofluorocarbons in air requires the preconcentration of these highly volatile species. In this paper, we present functionalized multiwalled carbon nanotubes as effective sorbents for a microtrap designed for chlorofluorocarbons preconcentration. Among the commercial carbons and carbon nanotubes studied, functionalization via carboxylation and propyl amine was most effective for dichlorofluoromethane and trichlorofluoromethane (Freon 11), which were selected as representative chlorofluorocarbons. The results show that carbon nanotubes functionalized with a polar groups led to as much as a 300% increase in breakthrough volume and the desorption bandwidth was reduced by 2.5 times. 相似文献