Antioxidant and Gastroprotective Activity of Suaeda fruticosa Forssk. Ex J.F.Gmel

Suaeda fruticosa Forssk. Ex J.F.Gmel is traditionally used for inflammatory and digestive disorders, as a carminative, and for diarrhea. This plant is widely distributed in Asia, Africa, and the Mediterranean region. Aqueous methanolic extract of S. fruticosa (Sf.Cr) was prepared and screened for phytoconstituents through qualitative and GC-MS analysis. Quantification of total phenolic and flavonoid contents was performed, while antioxidant capacity was determined by DPPH, CUPRAC, FRAP, and ABTS assays. The gastroprotective activity was assessed in an ethanol-induced ulcer model. Gastric secretory parameters and macroscopic ulcerated lesions were analyzed and scored for ulcer severity. After scoring, histopathology was performed, and gastric mucus contents were determined. Oral pre-treatment of Sf.Cr demonstrated significant gastroprotection. The gastric ulcer severity score and ulcer index were reduced while the %-inhibition of ulcer was increased dose-dependently. The Sf.Cr significantly elevated the pH of gastric juice, while a decrease in total acidity and gastric juice volume was observed. Histopathology demonstrated less oedema and neutrophil infiltration in gastric mucosa of rats pre-treated with the Sf.Cr in comparison to ethanol-intoxicated animals. Furthermore, the gastric mucus contents were increased as determined by alcian blue binding. Sf.Cr showed marked gastroprotective activity, which can be attributed to antioxidant, antisecretory, and cytoprotective effects.     

Dielectric relaxation of chlorinated polyvinyl chloride (CPVC) stabilized with cyanoguanidine

Dielectric spectra of CPVC stabilized with cyanoguanidine were studied in the temperature range 300–450 K and frequency range 10 kHz to 1 MHz. In these conditions, only one clear dielectric relaxation band (α-type) associated with dipolar polarization was observed. Dielectric losses was found to directly proportional to the number of dipoles (N) which reflects the orientational distribution of polymer chains in the amorphous region, at which dielectric losses concerned. Calculations of the dielectric modulus M′(T) at low temperature indicate that there is a role of the electrode polarization in the relaxation process. Dielectric loss data were used to calculate the activation enthalpy by two different methods, the obtained value was 450 kJ/mol.     

Structural,luminescence and biological studies of trivalent lanthanide complexes with N,N′-bis(2-hydroxynaphthylmethylidene)-1,3-propanediamine Schiff base ligand

New eight lanthanide metal complexes were prepared. These complexes were characterized by elemental analysis, molar conductivity measurements, spectral analysis (¹H NMR, FT-IR, UV–vis), luminescence and thermal gravimetric analysis. All Ln(III) complexes were 1:1 electrolytes as established by their molar conductivities. The microanalysis and spectroscopic analysis revealed eight-coordinated environments around lanthanide ions with two nitrate ligands behaving in a bidentate manner. The other four positions were found to be occupied with tetradentate L_III ligand. Tb–L_III and Sm–L_III complexes exhibited characteristic luminescence emissions of the central metal ions and this was attributed to efficient energy transfer from the ligand to the metal center. The L_III and Ln–L_III complexes showed antibacterial activity against a number of pathogenic bacteria.     

A Study of the Thermal Hysteresis in AgNO3

The reversible phase transformation of AgNO₃ is studied. Dielectric constant, d.c. resistivity, differential thermal analysis (DTA) and dilatometric measurements show the occurrence of a reversible phase transition II→I at 160°C with heat of transformation H = 0.78 kcal/mol. The thermal hysteresis in this reversible transformation is examined, the magnitude of the temperature hysteresis does not exceed 12°C. An acceptable agreement is observed between the measured values of the transition temperature obtained by three different experimental techniques. The dilatometric analysis shows that this transition is accompanied by thermal shrinkage with relative shrinkage coefficient 8 × 10^?4. Thermal analysis are also used to get thermodynamic and kinetic data of this phase transition. The temperature dependence of the dielectric constant and d.c. resistivity for single crystals as well as polycrystalline samples of AgNO₃ have clearly located and confirm the phase transitions II→I→II with a strong support to its thermal hysteresis character. The conduction mechanism is found to be activated by energy 0.12 eV for phase I and 0.36 eV for phase II. The observed thermal behaviour of the various measured parameters is attributed to orientational disorder of the nitrate group leading to an order-disorder phase transition which is reported here for first time in AgNO₃.     

Stability Constants for the Equilibrium Models of Iron(III) with Several Biological Buffers in Aqueous Solutions

The complexation equilibria of Fe(III) with two buffer families, which are ubiquitous in biological system studies, were studied by potentiometric measurements at a constant ionic strength of I = 0.1 mol·dm^?3 NaNO₃ in aqueous solutions at 298.15 K. The members of TRIS family are tris(hydroxymethyl)aminomethane (TRIS), N-[tris(hydroxymethyl)methyl]-2-aminoethanesulfonic acid (TES), N-[tris(hydroxymethyl)methyl]-3-aminopropanesulfonic acid (TAPS), N-[tris(hydroxymethyl)methyl]-3-amino-2-hydroxypropanesulfonic acid (TAPSO), and N-tris(hydroxymethyl)methyl-4-aminobutanesulfonic acid (TABS) buffers. The members of morpholine family are 4-morpholineethanesulfonic acid (MES), 4-morpholinepropanesulfonic acid (MOPS), 3-morpholino-2-hydroxypropanesulfonic acid (MOPSO), and 4-(N-morpholino) butanesulfonic acid (MOBS) buffers. The overall stability constants were determined from pH-metric data using the least-squares curve-fitting program HYPERQUAD 2008. Based on the best-fit results, the species formed at equilibrium are ML, ML₂, ML₂H_?1, and ML₃ in the systems with TRIS family buffers. The complex species ML, ML₂, ML₂H_?1, and MLH_?1 are formed in the MOPSO-containing system, while ML, ML₂, and ML₂H_?1 are formed in the systems with MES, MOPS, and MOBS. The stabilities of the complexes fall in the order TABS > TRIS > TAPS > TAPSO > TES and MOBS > MOPS > MOPSO > MES for the TRIS family and morpholine families, respectively.     

Study of the nanostructure of γ‐irradiated high‐density polyethylene/carbon black composite and its durability as geomembrane

The degradation of the nearby generation of high‐density polyethylene (HDPE) loaded with 2.5% of carbon black (CB) content (ie, HDPE/CB composites) is studied experimentally with the end goal of radiation safety applications. The impact of various γ‐irradiation doses in the air on the nanostructure of free volume and durability has been researched. The free volume was evaluated utilizing the positron annihilation lifetime (PAL) technique while the durability was contemplated by measuring the mechanical properties such as strain, elongation at break, and tear resistance. The electrical conductivity was explored to demonstrate the impact of the irradiation dose on the conductivity of the samples. Surface morphology studies using a scanning electron microscope (SEM) showed the surface fracture of HDPE/CB composites for unirradiated and irradiated samples. The surface roughness of the HDPE/CB GMs increases with increasing the irradiation dose. Among various uses of HDPE/CB composites, sheets are liners of dumps used to dispose of interim storage for Low and Medium Level Waste of NORMs and TENORMs. HDPE Geomembrane liners proved its utilization from the results of present research of electrical, mechanical tests, and SEM morphology to have the required resistance to weather conditions.     

Nanostructured Lipid Carriers (NLC) for Biologically Active Green Tea and Fennel Natural Oils Delivery: Larvicidal and Adulticidal Activities against Culex pipiens

(1) Background: The control of mosquitoes with essential oils is a growing demand. (2) Methods: This study evaluated the novel larvicidal and adulticidal activity of fennel and green tea oils and their nanostructured lipid carriers (NLC) against Culex pipiens (C. pipiens) in the laboratory, field conditions and evaluated their effect against non-target organisms. SLN type II nanoformulations were synthesized and characterized using dynamic light scattering (DLS), zeta potential and transmission electron microscope. (3) Results: The synthesized NLCs showed spherical shaped, homogenous, narrow, and monomodal particle size distribution. The mortality percent (MO%) post-treatment (PT) with 2000 ppm for 24 h with fennel oil and NLC fennel (NLC-F) reached 85% (LC₅₀ = 643.81 ppm) and 100% (LC₅₀ = 251.71), whereas MO% for green tea oil and NLC green tea (NLC-GT) were 80% (LC₅₀ = 746.52 ppm) and 100% (LC₅₀ = 278.63 ppm), respectively. Field trial data showed that the larval reduction percent of fennel oil and NLC-F reached 89.8% and 97.4%, 24 h PT and the reduction percent of green tea oil and NLC-GT reached 89% and 93%, 24 h PT with persistence reached 8 and 7 days, for NLC-F and NLC-GT, respectively. The adulticidal effects showed that NLC-F and NLC-GT (100% mortality) were more effective than fennel and green tea oils (90.0% and 83.33%), with 24 h PT, respectively. Moreover, their reduction of adult density after spraying with LC₉₅ X2 for 15 min, with fennel oil, NLC-F, and green tea oil, NLC-GT were 83.6%, 100%, 79.1%, and 100%, respectively, with persistence (>50%) lasting for three days. The predation rate of the mosquitofish, Gambusia affinis, and the bug, Sphaerodema urinator, was not affected in both oil and its NLC, while the predation rate of the beetle, Cybister tripunctatus increased (66% and 68.3%) by green tea oil and NLC-GT, respectively. (4) Conclusions: NLCs nanoformulation encapsulated essential oils was prepared successfully with unique properties of size, morphology, and stability. In vitro larvicidal and adulticidal effects against C. pipiens supported with field evaluations have been performed using essential oils and their nanoformulations. The biological evaluation of nanoformulations manifested potential results toward both larvicidal and adulticidal compared to the essential oils themselves, especially NLC encapsulated fennel oil which had promising larvicidal and adulticidal activity.     

Photoconductivity,Antioxidant, and Antimicrobial Activities of Some Acenaphthenequinone Derivatives

Russian Journal of General Chemistry - Photoconductive acenaphthenequinone derivatives have been synthesized by a one-pot process of acenaphthenequinone with different aromatic hydrazides...