Hydrothermal-assisted synthesis of Sr-doped SnS nanoflower catalysts for photodegradation of metronidazole antibiotic pollutant in wastewater promoted by natural sunlight irradiation.

In this study, we report a facile hydrothermal synthesis of strontium-doped SnS nanoflowers that were used as a catalyst for the degradation of antibiotic molecules in water. The prepared sample was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and ultraviolet-visible absorption spectroscopy (UV-Vis). The photocatalytic ability of the strontium-doped SnS nanoflowers was evaluated by studying the degradation of metronidazole in an aqueous solution under photocatalytic conditions. The degradation study was conducted for a reaction period of 300 min at neutral pH, and it was found that the degradation of metronidazole reached 91%, indicating the excellent photocatalytic performance of the catalyst. The influence of experimental parameters such as catalyst dosage, initial metronidazole concentration, initial reaction pH, and light source nature was optimized with respect to metronidazole degradation over time. The reusability of the strontium-doped SnS nanoflowers catalyst was investigated, and its photocatalytic efficiency remained unchanged even after four cycles of use.

Optical and structural properties of composites films based on Ce3+ -doped yttrium aluminium garnet nanoparticles embedded in polystyrene.

In the present work, attempts have been made to prepare scintillating nanoparticle composite films of Ce3+ -doped Y3 Al5 O12 (YAG:Ce) embedded in a polystyrene (PS) polymer. A YAG:Ce phosphor has been previously synthesized using the sol-gel method. YAG:Ce-PS composite films of 250 ± 30 µm thickness were prepared using a solvent casting procedure with different PS/solvent concentration and a different mass ratio between nanoparticles of YAG:Ce and PS. X-ray diffraction analysis confirmed that the YAG:Ce powders were successfully prepared. Using thermogravimetric analyses and differential scanning calorimetry, we found that the glass transition temperature (Tg) and thermal degradation were shifted to higher temperatures for composite films relative to pure PS. Photoluminescence showed the yellow emission of the Ce3+ -doped YAG phosphors, which was attributed to the 5d→4f transition of Ce3+ ion and the intensity of the emissions changed with the mass ratio of the YAG:Ce nanoparticles incorporated in the polymer and with the concentration of the polymer solution.

Synthesis, in silico study (DFT, ADMET) and crystal structure of novel sulfamoyloxy-oxazolidinones: Interaction with SARS-CoV-2.

A new series of sulfamoyloxyoxazolidinone (SOO) derivatives have been synthesized and characterized by single-crystal X-ray diffraction, NMR, IR, MS and EA. Chemical reactivity and geometrical characteristics of the target compounds were investigated using DFT method. The possible binding mode between SOO and Main protease (Mpro) of SARS-CoV-2 and their reactivity were studied using molecular docking simulation. Single crystal X-ray diffraction showed that SOO crystallizes in a monoclinic system with P 2 1 space group. The binding energy of the SARS-CoV-2/Mpro-SOO complex and the calculated inhibition constant using docking simulation showed that the active SOO molecule has the ability to inhibit SARS-CoV2. We studied the prediction of absorption, distribution, properties of metabolism, excretion and toxicity (ADMET) of the synthesized molecules.

Biological Activity of Pumpkin Byproducts: Antimicrobial and Antioxidant Properties.

Pumpkin fruits are widely appreciated and consumed worldwide. In addition to their balanced nutritional profile, pumpkin species also present valuable bioactive compounds that confer biological and pharmacological properties to them. However, the seeds, peels, and fibrous strands resulting from pumpkin processing are still poorly explored by the food industry. The current study used those fruit components from the genotypes of pumpkin that are economically significant in Portugal and Algeria to produce bioactive extracts. In order to support their usage as preservatives, their phenolic content (HPLC-DAD-ESI/MS) and antioxidant (OxHLIA and TBARS) and antimicrobial properties (against eight bacterial and two fungal strains) were assessed. In terms of phenolic profile, the peel of the Portuguese 'Common Pumpkin' showed the most diversified profile and also the highest concentration of total phenolic compounds, with considerable concentrations of (-)-epicatechin. Regarding the antioxidant capacity, the seeds of 'Butternut Squash' from both countries stood out, while the fibrous strands of Portuguese 'Butternut Squash' and the seeds of Algerian 'Gold Nugget Pumpkin' revealed the strongest antimicrobial activity. The bioactive compounds identified in the pumpkin byproducts may validate their enormous potential as a source of bio-based preservatives that may enhance consumers' health and promote a circular economy.

Photodegradation of tartrazine dye favored by natural sunlight on pure and (Ce, Ag) co-doped ZnO catalysts.

In this work, the synthesis of pure and (Ce, Ag) co-doped ZnO was successfully accomplished using a solvothermal process. The synthesized samples were characterized by ultraviolet-visible spectroscopy, X-ray diffraction, and scanning electron microscopy. The photocatalytic ability of the samples is estimated through degradation of tartrazine in aqueous solution under photocatalytic conditions. The degradation study carried out for a reaction period of 90 min at and a free pH = 6.0 found that dye degradation is 44.82% for pure ZnO and 98.91% for (Ce, Ag) co-doped ZnO samples, indicating its excellent photocatalytic ability. Tartrazine mineralization was also studied by calculating the degradation of chemical oxygen demand. The effect of operating parameters such as catalyst dose, initial concentration of tartrazine, initial reaction pH, and nature of light source has been optimized for tartrazine degradation as a function of time. The reusability of ZnO and (Ce, Ag) co-doped ZnO catalysts was studied and its photocatalytic efficiency was found to be unchanged, even after six cycles of use. The mechanism of photocatalytic activity was also proposed.

Crystal structure, chemical reactivity, kinetic and thermodynamic studies of new ligand derived from 4-hydroxycoumarin: Interaction with SARS-CoV-2.

Currently, Covid-19 pandemic infects staggering number of people around the globe and causes a high rate of mortality. In order to fight this disease, a new coumarin derivative ligand (4-[(pyridin-3-ylmethyl) amino]-2H-chromen-2-one) (LTA) has been synthesized and characterized by single-crystal X-ray diffraction, NMR, ATR, UV-Visible and cyclic voltammetry. Chemical reactivity, kinetic and thermodynamic studies were investigated using DFT method. The possible binding mode between LTA and Main protease (Mpro) of SARS-CoV-2 and their reactivity were studied using molecular docking simulation. Single crystal X-ray diffraction showed that LTA crystallizes in a monoclinic system with P2 1  space group. The reactivity descriptors such as nucleophilic index confirm that LTA is more nucleophile, inducing complexation with binding species like biomolecules. The kinetic and thermodynamic parameters showed that the mechanism of crystal formation is moderately exothermic. The binding energy of the SARS-CoV-2/Mpro-LTA complex and the calculated inhibition constant using docking simulation showed that the active LTA molecule has the ability to inhibit SARS-CoV-2.

Hemi-Synthesis of Chiral Imine, Benzimidazole and Benzodiazepines from Essential Oil of Ammodaucus leucotrichus subsp. leucotrichus.

The hemi-synthesis of chiral imine, benzimidazole and benzodiazepine structures is reported by the condensation of (S)-(-)-perillaldehyde, the major phytochemical of Ammodaucus leucotrichus subsp. leucotrichus essential oil, with different amine derivatives of 2,3-diaminomaleonitrile, o-phenylenediamine and 3-[(2-aminoaryl)amino]dimedone. The reaction proceeds in situ at ambient temperature without prior isolation of the natural (S)-(-)-perillaldehyde. Final products precipitate in the ethanolic reaction medium. 2D NMR and single-crystal X-ray diffraction studies were used to unequivocally characterize the structures in solution and in the solid state, respectively. Chiral HPLC analysis confirms the formation of unique enantiomers and diastereomeric mixtures.

Removal of Cr(VI) from Aqueous Solutions Using Amino-Functionalized Carbon Nanospheres Adsorbents.

Carbon nanospheres were prepared and functionalized with carboxyl acid groups (CNS-CA), then reacted with 3-aminopropyltriethoxysilane to introduce amino groups onto the surface (CNS-NH2) by post-synthesis grafting. CNS-NH2 was acidified in order to convert the amino groups (-NH2) into ammonium moieties (). Various techniques such as N2 physisorption, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetry, X-ray photoelectron spectroscopy, and transmission electron microscopy were used to characterize the nanospheres. The removal of chromium ions from aqueous solution using was investigated. Factors influencing the uptake of Cr(VI) ions such as solution pH, adsorbent dose, and initial Cr(VI) ion concentration were investigated. Equilibrium adsorption data fitted the Langmuir model very well. The adsorption maximum capacity of Cr(VI) was found to be 52.38 mg/g. The reusability of results indicated that it can be reused five times successfully without loss of adsorption capacity.

Removal of Malachite Green by Poly(acrylamide-co-acrylic acid) Hydrogels: Analysis of Coulombic and Hydrogen Bond Donor-Acceptor Interactions.

Water pollution caused by dyes poses a significant threat to life on earth. Poly(acrylamide-co-acrylic acid) hydrogels are widely used to treat wastewater from various pollutants. This study aims to examine the removal of malachite green (MG), a harmful and persistent dye that could cause extensive environmental damage, from an aqueous solution by adjusting the initial concentration of acrylamide (AM) and the degree of copolymer crosslinking. The copolymer hydrogels efficiently eliminate MG in a brief timeframe. The most successful hydrogel accomplished a removal rate exceeding 96%. The copolymer of 4 wt % 1,6-hexanediol diacrylate and a concentration of 100 mg/mL AM was effective. The degree of swelling was affected by crosslinking density as expected, with low crosslinking ratios resulting in significant swelling and high ratios resulting in less swelling. To evaluate the results, a docking approach was used which presented three crosslinked models: low, medium, and high. The copolymer-dye hydrogel system displayed robust hydrogen bonding interactions, as confirmed by the high quantities of both donors and acceptors. It was determined that MG contains six rotatable bonds, enabling it to adapt and interact with the copolymer chains. The dye and copolymer enhance H-bond formation by providing two hydrogen bond donors and 16 hydrogen bond acceptors, respectively. Through capitalizing on cationic and anionic effects, the ionic MG/copolymer hydrogel system improves retention efficiency by enhancing attraction between opposing charges. It is interesting to note that the synthesized copolymer is able to remove 96.4% of MG from aqueous media within one hour of contact time.

Efficient synthesis and antitumor activity of novel oxazaphosphinane derivatives: X-ray crystallography, DFT study and molecular docking.

A novel potentially biologically active oxazaphosphinane derivatives was synthesized by facile synthetic approaches from the combination of hydroxyaniline, aldehyde, and triethylphosphite. The crystal structure of compound 1b has been determined. Single crystals belong to the triclinic system with p - 1 space. The relative in vitro antitumor activity against human cell lines (PRI, K562, and JURKAT) of these derivatives in comparison to chlorombucil is reported. All synthesized compound showed excellent activity with IC50 value of 0.014-0.035 mM. The binding energy of the Epidermal growth factor receptor (EGFR)-oxazaphosphinane complex and the calculated inhibition constant using docking simulation showed that all molecules has the ability to inhibit EGFR therapeutic target. In addition, DFT calculation has been used to analyze the electronic and geometric characteristics.Communicated by Ramaswamy H. Sarma.

Facile green in situ hemisynthesis of new chiral chromeno-pyrimidine derivatives: antibacterial, antioxidant activities and molecular docking study.

A hemisynthesis 'in situ' reaction of (thio)barbituric acids with an α,ß-unsaturated aldehyde using perillaldehyde from Ammodaucus leucotrichus essential oil, afforded chromeno-pyrimidine derivatives B-1 and B-2. The reaction was carried out in water and water/ethanol medium without a catalyst. The obtained pyrimidines were identified by their spectral 1H,13C, Dept-135, HMBC, HSQC, COSY, and NOESY 2D. The antioxidant activity of both compounds was evaluated using different in vitro methods (DPPH, ABTS, and CUPRAC). The hemisynthesized molecules exhibited a bacteriostatic effect against ten tested gram (+) and gram (-) strains. According to the molecular docking analysis, B-1 showed lower binding energies compared to B-2 against (PDB: 1HD2) and (PDB: 1KZN) targets, which is in agreement with the ABTS and E. Coli assays. Furthermore, a probable promising anti-HIV activity was noticed against reverse transcriptase (PDB: 2RKI), a key enzyme for HIV replication. The ADME properties calculations showed no Lipinski's rule violation for both compounds.

Novel N-acylsulfonamides: Synthesis, in silico prediction, molecular docking dynamic simulation, antimicrobial and anti-inflammatory activities.

Microbial resistance to drugs currently traded in the market is a serious problem in modern medicine. In this field of research, we synthesized a novel N-acylsulfonamides (NAS) derivatives starting from commercially available compounds; morpholine, isocyanate of chlorosulfonyl and alcohols. The in vitro antimicrobial potential of synthesized compounds was screened against 04 Gram-negative bacteria; Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumannii, 02 Gram-positive bacteria: Streptococcus sp, Staphylococcus aureus and 07 yeasts and fungi: Candida albicans, Candida spp, Penicillum spp, Aspegillus sp, Aspergillus flavus, Fusarium sp, and Cladosporium spp. The results of inhibition growth were compared with standard antimicrobial drugs with the goal of exploring their potential antimicrobial activity. In addition, the anti-inflammatory activity of the synthesized compounds was determined in-vitro by protein denaturation method. The obtained bioactivity results were further validated by in silico DFT (Density Functional Theory), ADME (Absorption-Distribution-Métabolisation-Excrétion), molecular docking studies and molecular dynamics simulations.Communicated by Ramaswamy H. Sarma.

Enhanced reactivity of the CuO-Fe2O3 intimate heterojunction for the oxidation of quinoline yellow dye (E104).

This research work describes the degradation of quinoline yellow (QY) in aqueous solutions by the heterogeneous Fenton and photo-Fenton processes in the presence of CuO/Fe2O3 photocatalyst. CuO/Fe2O3 derived from LDH structure was synthesized by the co-precipitation method. The physiochemical characteristics of CuO/Fe2O3 were described by XRD, TEM/SEM, BET surface area, and FTIR techniques. The effects of pH, H2O2 concentration, dye concentration, catalyst dose, reaction temperature, and reusability of catalyst on the QY decolorization efficiency were studied. The results indicated that a complete removal of QY was achieved within 150 min, when the H2O2 and QY concentrations were 27.6 mM and 100 mg/L, respectively. The rate constants for QY removal by the heterogeneous Fenton system were calculated, and the experimental data were found to fit the pseudo-first order model. Under optimal conditions, the rate constants were, respectively, 0.02032 and 0.01715 min-1 for the photo-Fenton and Fenton systems; this means that the addition of light has not a noticeable effect.

Synthesis and Characterization of Copolymers and Nanocomposites from Limonene, Styrene and Organomodified-Clay Using Ultrasonic Assisted Method.

In the present work, we report a simple synthesis method for preparation of copolymers and nanocomposites from limonene and styrene using clay as a catalyst. The copolymerization reaction is carried out by using a proton exchanged clay as a catalyst called Mag-H+. The effect of temperature, reaction time and amount of catalyst were studied, and the obtained copolymer structure (lim-co-sty) is characterized by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (1H-NMR) and differential scanning calorimetry (DSC). The molecular weight of the obtained copolymer is determined by gel permeation chromatography (GPC) and is about 4500 g·mol-1. The (lim-co-sty/Mag 1%, 3%, 7% and 10% by weight of clay) nanocomposites were prepared through polymer/clay mixture in solution method using ultrasonic irradiation, in the presence of Mag-CTA+ as green nano-reinforcing filler. The Mag-CTA+ is organophilic silicate clay prepared through a direct exchange process, using cetyltrimethylammonuim bromide (CTAB). The prepared lim-co-sty/Mag nanocomposites have been extensively characterized by FT-IR spectroscopy, X-ray diffraction (XRD), scanning electronic microscopy (SEM) and transmission electronic microscopy (TEM). TEM analysis confirms the results obtained by XRD and clearly show that the obtained nanocomposites are partially exfoliated for the lower amount of clay (1% and 3% wt) and intercalated for higher amounts of clay (7% and 10% wt). Moreover, thermogravimetric analysis (TGA) indicated an enhancement of thermal stability of nanocomposites compared with the pure copolymer.

Hemisynthesis of coumarin derivatives from Ammodaucus leucotrichus oil extract: organobase-catalyzed reaction, analytical study by diffusion-ordered spectroscopy NMR and differential scanning calorimetry.

This paper presents an in-depth chemical and analytical study of a natural substance extracted from Ammodaucus leucotrichus Coss. & Dur and its derivatives after hemisynthesis. The analysis was performed using Diffusion-Ordered Spectroscopy (NMR DOSY) and Differential Scanning Calorimetry (DSC) as general methods. The results show an interesting chemical reactivity towards coumarin-derived bisnucleophiles (4-hydroxycoumarin and triacetic acid lactone), and products obtained by hemisynthesis of pyrano[4,3-b]pyrane derivatives following Knoevenagel condensation and Michael's addition on this natural substance with the use of 4-pyrolidinopyridine organobase as catalyst.

Identification of Algerian field-caught mosquito vectors by MALDI-TOF MS.

Vector-borne diseases represent a real threats worldwide, in reason of the lack of vaccine and cure for some diseases. Among arthropod vectors, mosquitoes are described to be the most dangerous animal on earth, resulting in an estimated 725,000 deaths per year due to their borne diseases. Geographical position of Algeria makes this country a high risk area for emerging and re-emerging diseases, such as dengue coming from north (Europe) and malaria from south (Africa). To prevent these threats, rapid and continuous surveillance of mosquito vectors is essential. For this purpose we aimed in this study to create a mosquito vectors locale database using MALDI-TOF mass spectrometry technology for rapid identification of these arthropods. This methodology was validated by testing 211 mosquitoes, including four species (Aedes albopictus, Culex pipiens, Culex quinquefasciatus, and Culiseta longiareolata), in two northern wilayahs of Algeria (Algiers and Bejaia). Species determination by MALDI TOF MS was highly concordant with reference phenotypic and genetic methods. Using this MALDI-TOF MS tool will allow better surveillance of mosquito species able to transmit mosquito borne diseases in Algeria.

Green Copolymers and Nanocomposites from Myrcene and Limonene Using Algerian Nano-Clay as Nano-Reinforcing Filler.

In this work, we report a new facile method for the preparation of myrcene-limonene copolymers and nanocomposites using a Lewis acid as a catalyst (AlCl3) and organo-modified clay as a nano-reinforcing filler. The copolymer (myr-co-lim) was prepared by cationic copolymerization using AlCl3 as a catalyst. The structure of the obtained copolymer is studied and confirmed by Fourier Transform Infrared spectroscopy, Nuclear Magnetic Resonance spectroscopy, and Differential Scanning Calorimetry. By improving the dispersion of the matrix polymer in sheets of the organoclay, Maghnite-CTA+ (Mag-CTA+), an Algerian natural organophilic clay, was used to preparenanocomposites of linear copolymer (myr-co-lim). In order to identify and assess their structural, morphological, and thermal properties, the effect of the organoclay, used in varyingamounts (1, 4, 7, and 10% by weight), and the preparation process were investigated. The Mag-CTA+ is an organophylic montmorillonite silicate clay prepared through a direct exchange process in which they were used as green nano-reinforcing filler. The X-ray diffraction of the resulting nanocomposites revealed a considerable alteration in the interlayer spacing of Mag-CTA+. As a result, interlayer expansion and myr-co-lim exfoliation between layers of Mag-CTA+ were observed. Thermogravimetric analysis provided information on the synthesized nanocomposites' thermal properties. Fourier transform infrared spectroscopy and scanning electronic microscopy, respectively, were used to determine the structure and morphology of the produced nanocomposites (myr-co-lim/Mag). The intercalation of myr-co-lim in the Mag-CTA+ sheets has been supported by the results, and the optimum amount of organoclay needed to create a nanocomposite with high thermal stability is 10% by weight. Finally, a new method for the preparation of copolymer and nanocomposites from myrcene and limonene in a short reaction time was developed.

Experimental and theoretical insights into copper corrosion inhibition by protonated amino-acids.

The effects of cysteine (Cys) and l-methionine (l-Met) on copper corrosion inhibition were examined in 1 M HNO3 solution for short and long exposure times. Potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) were used. The EIS determined the potential for zero charges of copper (PZC) in the inhibitor solution. SEM and AFM have been used to study material surfaces. Energy-dispersive X-ray spectroscopy (EDS) was used to identify surface elemental composition. DFT and molecular dynamics simulations explored the interaction between protonated amino acids and aggressive media anions on a copper (111) surface.

Pharmacological Investigations in Traditional Utilization of Alhagi maurorum Medik. in Saharan Algeria: In Vitro Study of Anti-Inflammatory and Antihyperglycemic Activities of Water-Soluble Polysaccharides Extracted from the Seeds.

The anti-inflammatory and antihyperglycemic effects of polysaccharides extracted from Alhagi maurorum Medik. seeds, spontaneous shrub collected in Southern of Algerian Sahara were investigated. Their water extraction followed by alcoholic precipitation was conducted to obtain two water-soluble polysaccharides extracts (WSPAM1 and WSPAM2). They were characterized using Fourier transform infrared, 1H/13C Nuclear Magnetic Resonance, Gas Chromatography-Mass Spectrometry and Size Exclusion Chromatography coupled with Multi-Angle Light Scattering. The capacity of those fractions to inhibit α-amylase activity and thermally induced Bovine Serum Albumin denaturation were also investigated. WSPAM1 and WSPAM2 were galactomannans with a mannose/galactose ratio of 2.2 and 2.4, respectively. The SEC-MALLS analysis revealed that WSPAM1 had a molecular weight of 1.4 × 106 Da. The investigations highlighted antinflammatory and antihyperglycemic effects in a dose-dependant manner of WSPAM1 and WSPAM2.

Molecular docking and dynamic studies of a potential therapeutic target inhibiting glyoxalase system: Metabolic action of the 3, 3 '- [3- (5-chloro-2-hydroxyphenyl) -3-oxopropane-1, 1-diyl] - Bis-4-hydroxycoumarin leads overexpression of the intracellular level of methylglyoxal and induction of a pro-apoptotic phenomenon in a hepatocellular carcinoma model.

Methylglyoxal is a dicarbonyl compound recruited as a potential cytotoxic marker, initially presents in cells and considered as a metabolite of the glycolytic pathway. Our aim is to demonstrate the inhibitory effect of 3, 3'-[3-(5-chloro-2-hydroxyphenyl)-3-oxopropane-1, 1-diyl] Bis (4-hydroxycoumarin) on the glyoxalase system, and indirectly its anticancer activity. The docking of OT-55 was conducted by using Flexible docking protocol, ChiFlex and libdock tools inside the active site of Glo-I indicated that both hydrogen bonding and hydrophobic interactions contributed significantly in establishing potent binding with the active site which is selected as a strong inhibitor with high scoring values and maximum Gibbs free energy. Coumarin-liposome formulation was characterized and evaluated in vivo against chemically induced hepatocarcinoma in Wistar rats. After Diethylnitrosamine (DEN) induction, microscopic assessment was realized; precancerous lesions were developed showing an increase of both tumor-associated lymphocyte and multiple tumor acini supported by the blood investigation. Our finding also suggested a preferential uptake of liposomes respectively in liver, kidney, lung, brain and spleen in the DEN-treated animals. OT-55 has also been shown to inhibit the activity of Glo-I in vitro as well as in DEN-treated rats. An abnormal high level of MGO of up to 50% was recorded followed by a reduction in glucose consumption and lactate dehydrogenase production validated in the positive control. MGO generates apoptosis as depicted by focal hepatic lesions. Also, no deleterious effects in the control group were observed after testing our coumarin but rather a vascular reorganization leading to nodular regenerative hyperplasia. Involved in the detoxification process, liver GSH is restored in intoxicated rats, while no changes are seen between controls. At the endothelial cell, OT-55 appears to modulate the release of NO only in the DEN-treated group. OT-55 would behave both as an anticancer agent but also as an angiogenic factor regarding results obtained.