Synthesis and characterization of magnetic poly(acrylic acid) hydrogel fabricated with cobalt nanoparticles for adsorption and catalytic applications

The present study aimed to synthesize poly(acrylic acid) hydrogel embedded with magnetic cobalt (Co) nanoparticles and to investigate their potential in adsorption and catalysis. The hydrogel was prepared by facile free radical polymerization reaction and Co nanoparticles were fabricated within hydrogel by reducing Co (II) ions using NaBH₄ as reducing agent. Co nanoparticles within hydrogel system imparted magnetic properties to the resulting composite gel and also increased the adsorption capacity. The swelling study of hydrogel was carried out by gravimetric analysis. Different functional groups were identified by Fourier Transform Infrared Spectroscopy and Transmission Electron Microscopy analysis was done to investigate dispersion of Co nanoparticles in hydrogel. The bare hydrogel along with Co nanoparticles loaded gel were tested as adsorbent systems for the removal of a cationic dye (methylene blue) from aqueous solution. 95% removal of methylene blue was achieved with a highest adsorption capacity of 836.5 mg/g of adsorbent. The famous adsorption isotherms were used to evaluate adsorption data. Results showed that Freundlich isotherm model was followed with R² value of 0.95. The hydrogel was also used for catalytic reduction in a toxic pollutant, i.e., 4-nitrophenol. Experimental data for 4-nitrophenol reduction followed pseudo first order kinetics model. Activation energy and apparent rate constant were calculated as 9.24 kJ/mol and 0.24 min⁻¹, respectively. Recycling of the magnetic poly(acrylic acid) hydrogel fabricated with Cobalt nanoparticles was carried out for four consecutive cycles and no significant loss in catalytic activity was observed.

     

Facile One-Pot Approach to the Synthesis of Alkyl Piperazine-1-carbodithioates as Hemolytic and Thrombolytic Agents

Russian Journal of Organic Chemistry - A polyethylene glycol (PEG)-promoted methodology has been utilized for synthesis of piperazine-based dithiocarbamates. One-pot reaction of N-methylpiperazine...     

Bio-Potency and Molecular Docking Studies of Isolated Compounds from Grewia optiva J.R. Drumm. ex Burret

In the study, two novel compounds along with two new compounds were isolated from Grewia optiva. The novel compounds have never been reported in any plant source, whereas the new compounds are reported for the first time from the studied plant. The four compounds were characterized as: 5,5,7,7,11,13-hexamethyl-2-(5-methylhexyl)icosahydro-1H-cyclopenta[a]chrysen-9-ol (IX), docosanoic acid (X), methanetriol mano formate (XI) and 2,2’-(1,4-phenylene)bis(3-methylbutanoic acid (XII). The anticholinesterase, antidiabetic, and antioxidant potentials of these compounds were determined using standard protocols. All the isolated compounds exhibited a moderate-to-good degree of activity against acetylcholinesterases (AChE) and butyrylcholinesterase (BChE). However, compound XII was particularly effective with IC₅₀ of 55 μg/mL (against AChE) and 60 μg/mL (against BChE), and this inhibitory activity is supported by in silico docking studies. The same compound was also effective against DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid) radicals with IC₅₀ values of 60 and 62 μg/mL, respectively. The compound also significantly inhibited the activities of α-amylase and α-glucosidase in vitro. The IC₅₀ values for inhibition of the two enzymes were recorded as 90 and 92 μg/mL, respectively. The in vitro potentials of compound XII to treat Alzheimer’s disease (in terms of AchE and BChE inhibition), diabetes (in terms of α-amylase and α-glucosidase inhibition), and oxidative stress (in terms of free radical scavenging) suggest further in vivo investigations of the compound for assessing its efficacy, safety profile, and other parameters to proclaim the compound as a potential drug candidate.     

GC-MS Analysis and Biomedical Therapy of Oil from n-Hexane Fraction of Scutellaria edelbergii Rech. f.: In Vitro,In Vivo,and In Silico Approach

The current study aimed to explore the crude oils obtained from the n-hexane fraction of Scutellaria edelbergii and further analyzed, for the first time, for their chemical composition, in vitro antibacterial, antifungal, antioxidant, antidiabetic, and in vivo anti-inflammatory, and analgesic activities. For the phytochemical composition, the oils proceeded to gas chromatography-mass spectrometry (GC-MS) analysis and from the resultant chromatogram, 42 bioactive constituents were identified. Among them, the major components were linoleic acid ethyl ester (19.67%) followed by ethyl oleate (18.45%), linolenic acid methyl ester (11.67%), and palmitic acid ethyl ester (11.01%). Tetrazolium 96-well plate MTT assay and agar-well diffusion methods were used to evaluate the isolated oil for its minimum inhibitory concentrations (MIC), minimum bactericidal concentration (MBC), half-maximal inhibitory concentrations (IC₅₀), and zone of inhibitions that could determine the potential antimicrobial efficacy’s. Substantial antibacterial activities were observed against the clinical isolates comprising of three Gram-negative bacteria, viz., Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa, and one Gram-positive bacterial strain, Enterococcus faecalis. The oils were also effective against Candida albicans and Fusarium oxysporum when evaluated for their antifungal potential. Moreover, significant antioxidant potential with IC₅₀ values of 136.4 and 161.5 µg/mL for extracted oil was evaluated through DPPH (1,1-Diphenyl-2-picryl-hydrazyl) and ABTS assays compared with standard ascorbic acid where the IC50 values were 44.49 and 67.78 µg/mL, respectively, against the tested free radicals. The oils was also potent, inhibiting the α-glucosidase (IC50 5.45 ± 0.42 µg/mL) enzyme compared to the standard. Anti-glucosidase potential was visualized through molecular docking simulations where ten compounds of the oil were found to be the leading inhibitors of the selected enzyme based on interactions, binding energy, and binding affinity. The oil was found to be an effective anti-inflammatory (61%) agent compared with diclofenac sodium (70.92%) via the carrageenan-induced assay. An appreciable (48.28%) analgesic activity in correlation with the standard aspirin was observed through the acetic acid-induced writhing bioassay. The oil from the n-hexane fraction of S. edelbergii contained valuable bioactive constituents that can act as in vitro biological and in vivo pharmacological agents. However, further studies are needed to uncover individual responsible compounds of the observed biological potentials which would be helpful in devising novel drugs.     

Facile Synthesis of 5-Aryl-N-(pyrazin-2-yl)thiophene-2-carboxamides via Suzuki Cross-Coupling Reactions,Their Electronic and Nonlinear Optical Properties through DFT Calculations

Synthesis of 5-aryl-N-(pyrazin-2-yl)thiophene-2-carboxamides (4a–4n) by a Suzuki cross-coupling reaction of 5-bromo-N-(pyrazin-2-yl)thiophene-2-carboxamide (3) with various aryl/heteroaryl boronic acids/pinacol esters was observed in this article. The intermediate compound 3 was prepared by condensation of pyrazin-2-amine (1) with 5-bromothiophene-2-carboxylic acid (2) mediated by TiCl₄. The target pyrazine analogs (4a–4n) were confirmed by NMR and mass spectrometry. In DFT calculation of target molecules, several reactivity parameters like FMOs (E_HOMO, E_LUMO), HOMO–LUMO energy gap, electron affinity (A), ionization energy (I), electrophilicity index (ω), chemical softness (σ) and chemical hardness (η) were considered and discussed. Effect of various substituents was observed on values of the HOMO–LUMO energy gap and hyperpolarizability. The p-electronic delocalization extended over pyrazine, benzene and thiophene was examined in studying the NLO behavior. The chemical shifts of ¹H NMR of all the synthesized compounds 4a–4n were calculated and compared with the experimental values.     

Design,synthesis and liquid crystalline behavior of ethyl 4-((4-alkoxyphenyl)diazenyl)benzoates

A series of ethyl 4-((4-alkoxyphenyl)diazenyl)benzoate is synthesized and the liquid crystalline behavior studied. Synthesized compounds are characterized by FTIR, ¹H-NMR, Mass and single crystal XRD. Differential scanning calorimetry was carried out to study the phase transitions and enthalpy changes. Polarizing optical microscopy revealed the mesogenic properties. These techniques revealed that three compounds (2a, 2b, 2f) exhibit liquid crystalline properties in the range of 80–104°C. POM exhibiting focal conical fan like texture which revealed the presence of smectic phases suggestive of their use in LCD and temperature sensing devices, besides 2c can be used as green emitter in OLEDs.     

Neuro-computing intelligent networks for entropy optimized MHD fully developed nanofluid flow with activation energy and slip effects

In this paper, the main focus of this research is to represent an intelligent computing model through an artificial backpropagated Levenberg-Marquardt neural network (ABP-LMNN) for entropy optimized magnetohydrodynamic fully developed nanofluid flow with slip and activation energy effects. In mathematical modeling, dimensionless non-linear ODEs represent the magnetohydrodynamic nanofluid flow model (MHD-NFM). A reference dataset of ABP-LMNN is constructed for diverse situations of MHD-NFM by discrepancy of parameters. The attained reference dataset (RD) is randomly utilized for validation, testing and training processes for ABP-LMNN are employed to examine the approximate solution of MHD-NFM is demonstrated by comparison of outcomes. The authentic performance of the ABP-LMNN is validated through accuracy in the phrase of error histogram, mean square error and regression learning. The thermal and solutal parameters upsurge both the thermal and the concentration gradients. Moreover, the velocity profiles are declined owing to an increase in the second-order slip parameter in the tangential direction of the flow.     

Antioxidants Isolated from Elaeagnus umbellata (Thunb.) Protect against Bacterial Infections and Diabetes in Streptozotocin-Induced Diabetic Rat Model

The increase in resistance of microbes against conventional drugs is currently a hot issue, whereas diabetes is another main cause of mortalities encountered throughout the world after cancer and heart attacks. New drug sources in the form of plants are investigated to get effective drugs for the mentioned diseases with minimum side effects. Elaeagnus umbellata Thunb. is a medicinal plant used for the management of stress related disorders like diabetes and other health complications. The active constituents of the chloroform extract derived from E. umbellata berries was isolated by silica gel column chromatography which were identified as morin, phloroglucinol, and 1-hexyl benzene through various spectroscopic techniques (electron ionization mass spectrometry, 1H-NMR, and 13C-NMR spectroscopy). The possible protective effects (antioxidant, antibacterial, and antidiabetic activity) of isolated compounds were evaluated using reported methods. Morin exhibited strong in vitro antiradical potential against DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid) radicals along with prominent antibacterial activities against selected bacterial strains (Escherichia coli, Bacillus cereus, Salmonella typhi, Klebsiella pneumonia, Pseudomonas aeruginosa and Proteus mirabilis). Among the isolated compounds the more potent one (morin) was assessed for its in vivo antidiabetic potential in streptozotocin-induced diabetic rat model. The in vivo effects observed were further confirmed in ex vivo experiments where the effect of isolated compound on antioxidant enzyme like glutathione peroxidase (GPx), total content of reduced glutathione (GSH), % DPPH inhibition, and the lipid peroxidation MDA (Malondialdehyde) level in pancreatic tissues homogenates were evaluated. In vivo morin at tested doses (2, 10, 15, 30 and 50 mg/kg body weight) significantly restored the alterations in the levels of fasting blood glucose level and body weight loss along with significant decrease in levels of cholesterol, triglycerides, low density lipoprotein, HbA1c level, and significantly increased the high-density lipoprotein in diabetic rats. Morin also effectively ameliorated the hepatic enzymes, and renal functions like serum creatinine. Morin significantly increased the antioxidant enzyme like GPx activity, GSH content, and % DPPH inhibition activity, while reduced the lipid peroxidation MDA (malondialdehyde) level in pancreatic tissues homogenates, and modification of histopathological changes in diabetic rats. Morin exhibited high antioxidant, antibacterial, and antidiabetic potentials as compared to phloroglucinol and 1-hexyl benzene, that could, therefore, be considered as a promising therapeutic agent to treat diabetes mellitus and bacterial infections.     

Two new triterpenoids from Zygophyllum eurypterum

Two new triterpenoids trivially named as atriplicoide A and B were isolated from the n-BuOH extract of the whole plant of Zygophyllum eurypterum. Based on EI-MS, IR, 1H- and 13C-NMR, and 2D-NMR (HMQC, HMBC, COSY and NOESY) data, the structures of the new compounds were determined as 30-carboxy-3beta,24-dihydroxy-urs-28,13beta-lactam-N-acetate (1) and 3beta,24-dihydroxyursan-28,13beta-olide (2).