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1.
Molecules ; 29(12)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38930959

RESUMO

We report the synthesis of two novel halogenated nitro-arylhimachalene derivatives: 2-bromo-3,5,5,9-tetramethyl-1-nitro-6,7,8,9-tetrahydro-5H-benzo[7]annulene (bromo-nitro-arylhimachalene) and 2-chloro-3,5,5,9-tetramethyl-1,4-dinitro-6,7,8,9-tetrahydro-5H-benzo[7]annulene (chloro-dinitro-arylhimachalene). These compounds were derived from arylhimachalene, an important sesquiterpene component of Atlas cedar essential oil, via a two-step halogenation and nitration process. Characterization was performed using 1H and 13C NMR spectrometry, complemented by X-ray structural analysis. Quantum chemical calculations employing density functional theory (DFT) with the Becke3-Lee-Yang-parr (B3LYP) functional and a 6-31++G(d,p) basis set were conducted. The optimized geometries of the synthesized compounds were consistent with X-ray structure data. Frontier molecular orbitals and molecular electrostatic potential (MEP) profiles were identified and discussed. DFT reactivity indices provided insights into the compounds' behaviors. Moreover, Hirshfeld surface and 2D fingerprint analyses revealed significant intermolecular interactions within the crystal structures, predominantly H-H and H-O contacts. Molecular docking studies demonstrate strong binding affinities of the synthesized compounds to the active site of protein 7B2W, suggesting potential therapeutic applications against various isolated smooth muscles and neurotransmitters.

2.
BMC Chem ; 18(1): 4, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172974

RESUMO

The development of biobased polymeric materials for wastewater purification has become a demand due to the growing need for water free of hazardous metal ions for safe purposes. The organic components of the OLLW including carbohydrates, phenolics, aromatic acids and others are cost-effective and sustainable choices for this application. This work focuses on a method for turning the organic components of liquid waste from the olive industry (OILW) into a foam-based value-added polymer that has several metal ion binding sites. The process of making the target polymers involved reacting the components of the OILW with hexamethylene diisocyante and 1,4-phnyelene diisocynate to create the polymeric materials LHMIDIC and LPDIC that are in foam forms with urethane linkages, respectively. The adsorption competence of the polymeric foams toward Pb(II) was evaluated as a function of various parameters including adsorbent dose, pH, temperature, initial ion concentration and time. The optimum parameters values that led to a quantitative removal of Pb(II) were identified. The obtained thermodynamic parameters showed that the adsorption by the two foams was spontaneous at room temperature. The isothermal and kinetic values showed that the adsorption by synthesized foams follows a second order kinetic and obeys the Langmuir isothermal model. The foams showed a high tendency for removing multi metal ions present in a real sample of wastewater. The original nature of the starting material used in making the foam, cost and the obtained results showed the potential of using the foam in a large-scale plants of wastewater purification.

3.
Foods ; 12(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37297464

RESUMO

Canola, Brassica napus L., is a major oilseed crop that has various uses in the food, feed, and industrial sectors. It is one of the most widely produced and consumed oilseeds in the world because of its high oil content and favorable fatty acid composition. Canola grains and their derived products, such as canola oil, meal, flour, and bakery products, have a high potential for food applications as they offer various nutritional and functional benefits. However, they are affected by various factors during the production cycle, post-harvest processing, and storage. These factors may compromise their quality and quantity by affecting their chemical composition, physical properties, functional characteristics, and sensory attributes. Therefore, it is important to optimize the production and processing methods of canola grains and their derived products to ensure their safety, stability, and suitability for different food applications. This literature review provides a comprehensive overview of how these factors affect the quality of canola grains and their derived products. The review also suggests future research needs and challenges for enhancing canola quality and its utilization in food.

4.
Plants (Basel) ; 12(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37050197

RESUMO

The purpose of this study was to determine the chemical composition of the essential oil of Lavandula officinalis from Morocco using the GC-MS technique and assess the antibacterial effects against seven pathogenic bacteria strains isolated from the food origins of Salmonella infantis, Salmonella kentucky, Salmonella newport, three serotypes of Escherichia coli (O114H8K11, O127K88ac, O127H40K11) and Klebsiella. Tests of sensitivity were carried out on a solid surface using the Disc Diffusion Method. Results showed that E. coli and S.newport were sensitive to Lavandula officinalis essential oil. Minimum inhibitory concentrations (MIC) were determined using the method of agar dilution. The antibacterial results showed that four strains (three serotypes of E. coli, and S. newport) were remarkedly sensitive to Lavandula officinalis essential oil, giving MIC values of 88.7 µg/mL and 177.5 µg/mL. The molecular docking of the main oil products with the E. coli target protein 1VLY, showed that eucalyptol and linalyl acetate bind efficiently with the active site of the target protein. In particular, eucalyptol showed a higher activity than gentamicin used as positive control with a binding energy of -5.72 kcal/mol and -5.55 kcal/mol, respectively.

5.
Int J Biol Macromol ; 239: 124328, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37019199

RESUMO

Contamination in water is due to various environmental pollutants from natural and anthropogen activities. To remove toxic metals from contaminated water, we developed a novel adsorbent in foam form based on an olive industry waste material. The foam synthesis involved oxidation of cellulose extracted from the waste to dialdehyde, functionalization of the cellulose dialdehyde with an amino acid group, reacting the functionalized cellulose with hexamethylene diisocyanate and p-phenylene diisocyanate to produce the target polyurethanes Cell-F-HMDIC and Cell-F-PDIC, respectively. The optimum condition for lead(II) adsorption by Cell-F-HMDIC and Cell-F-PDIC were determined. The foams show the ability to quantitatively remove most of metal ions present in a real sample of sewage. The kinetic and thermodynamic studies confirmed a spontaneous metal ion binding to the foams with a second pseudo-order adsorption rate. The adsorption study revealed it obeys the Langmuir isotherm model. The experimental Qe values of both foams Cell-F-PDIC and Cell-F-HMDIC were 2.1929 and 2.0345 mg/g, respectively. Monte Carlo (MC) and Dynamic (MD) and simulations showed excellent affinity of both foams for lead ions with high adsorption negative energy value indicating vigorous interactions of Pb(II) with the adsorbent surface. The results indicate the usefulness of the developed foam in commercial applications. ENVIRONMENTAL IMPLICATION: Elimination of metal ions from contaminated environments is important for a number of reasons. They are toxic to humans via interaction with biomolecules, resulting in disruption of the metabolism and biological activities of many proteins. They are toxic to plants. Industrial effluents and/or wastewater discharged from production processes, contain a considerable amount of metal ions. In this work, the use of naturally produced materials, such as olive waste biomass, as adsorbents for environmental remediation has received great attention. This biomass represents unused resources and presents serious disposal problems. We demonstrated that such materials are capable of selectively adsorbing metal ions.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Purificação da Água , Humanos , Celulose/química , Poliuretanos , Aminoácidos , Metais , Purificação da Água/métodos , Íons , Água , Adsorção , Poluentes Químicos da Água/química , Cinética , Concentração de Íons de Hidrogênio
6.
Polymers (Basel) ; 15(4)2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36850079

RESUMO

In this work, we present a process for converting olive industry solid waste (OISW) into a value-added material with ionic receptors for use in the removal of toxic metal ions from wastewater. This 3D polymer is a promising adsorbent for large-scale application, since it is a low-cost material made from agricultural waste and showed exceptional performance. The synthesis of the network polymer involved the carboxymethylation of OISW and curing of the carboxymethylated OISW at an elevated temperature to promote the formation of ester linkages between OISW's components. FT-IR, atomic force microscopy, and thermal analysis were performed on the crosslinked product. The adsorption efficiency of the crosslinked carboxymethylated OISW toward Pb(II), Cu(II), and other toxic metal ions present in sewage was evaluated as a function of adsorbent dose, temperature, pH, time, and initial metal ion. The percentage removal of about 20 metal ions present in a sewage sample collected from a sewer plant located in the Palestinian Territories was determined. The adsorption efficiency did not drop even after six cycles of use. The kinetic study showed that the adsorption process follows the Langmuir isotherm model and the second-order adsorption rate. The experimental Qe values of 13.91 and 13.71 mg/g were obtained for Pb(II) and Cu(II) removal, respectively. The thermodynamic results confirm the spontaneous metal bonding to the receptor sites of the crosslinked carboxymethylated OISW.

7.
Polymers (Basel) ; 16(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38201750

RESUMO

This paper presents a novel cheminformatics approach for the design and synthesis of hydroxyapatite/collagen nanocomposites, which have potential biomedical applications in tissue engineering, drug delivery, and orthopedic and dental implants. The nanocomposites are synthesized by the co-precipitation method with different ratios of hydroxyapatite and collagen. Their mechanical, biological, and degradation properties are analyzed using various experimental and computational techniques. Attenuated total reflection-Fourier-transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction unveil the low crystallinity and nanoscale particle size of hydroxyapatite (22.62 nm) and hydroxyapatite/collagen composites (14.81 nm). These findings are substantiated by scanning electron microscopy with energy-dispersive X-ray spectroscopy, confirming the Ca/P ratio between 1.65 and 1.53 and attesting to the formation of non-stoichiometric apatites in all samples, further validated by molecular simulation. The antimicrobial activity of the nanocomposites is evaluated in vitro against several bacterial and fungal strains, demonstrating their medical potential. Additionally, in silico analyses are performed to predict the absorption, distribution, metabolism, and excretion properties and the bioavailability of the collagen samples. This study paves the way for the development of novel biomaterials using chemoinformatics tools and methods, facilitating the optimization of design and synthesis parameters, as well as the prediction of biological outcomes. Future research directions should encompass the investigation of in vivo biocompatibility and bioactivity of the nanocomposites, while exploring further applications and functionalities of these innovative materials.

8.
Plants (Basel) ; 13(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38202397

RESUMO

Rosmarinus officinalis L. compounds, especially its main polyphenolic compounds, carnosic acid (CA) and rosmarinic acid (RA), influence various facets of cancer biology, making them valuable assets in the ongoing fight against cancer. These two secondary metabolites exhibit formidable antioxidant properties that are a pivotal contributor against the development of cancer. Their antitumor effect has been related to diverse mechanisms. In the case of CA, it has the capacity to induce cell death of cancer cells through the rise in ROS levels within the cells, the inhibition of protein kinase AKT, the activation of autophagy-related genes (ATG) and the disrupt mitochondrial membrane potential. Regarding RA, its antitumor actions encompass apoptosis induction through caspase activation, the inhibition of cell proliferation by interrupting cell cycle progression and epigenetic regulation, antioxidative stress-induced DNA damage, and interference with angiogenesis to curtail tumor growth. To understand the molecular interaction between rosemary compounds (CA and RA) and a protein that is involved in cancer and inflammation, S100A8, we have performed a series of molecular docking analyses using the available three-dimensional structures (PDBID: 1IRJ, 1MR8, and 4GGF). The ligands showed different binding intensities in the active sites with the protein target molecules, except for CA with the 1MR8 protein.

9.
Polymers (Basel) ; 14(20)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36297842

RESUMO

Water purification from toxic metals was the main objective of this work. A composite in film form was prepared from the biomaterials hydroxyapatite, chitosan and glycerol using the dissolution/recrystallization method. A nanoparticle-based film with a homogenous and smooth surface was produced. The results of total reflectance infrared spectroscopy (ATR-FTIR) and thermal gravimetric analysis (TGA/DTA) demonstrated the presence of a substantial physical force between composite components. The composite was tested for its ability to absorb Cd2+ and Zn2+ ions from aqueous solutions. Cd2+ and Zn2+ adsorption mechanisms are fit using the Langmuir model and the pseudo-second-order model. Thermodynamic parameters indicated that Cd2+ and Zn2+ ion adsorption onto the composite surface is spontaneous and preferred at neutral pH and temperatures somewhat higher than room temperature. The adsorption studies showed that the maximum adsorption capacity of the HAp/CTs bio-composite membrane for Cd2+ and Zn2+ ions was in the order of cadmium (120 mg/g) > Zinc (90 mg/g) at an equilibrium time of 20 min and a temperature of 25 °C. The results obtained on the physico-chemical properties of nanocomposite membranes and their sorption capacities offer promising potential for industrial and biological activities.

10.
Polymers (Basel) ; 14(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35683819

RESUMO

The aim of this study is to develop a new, efficient, and inexpensive natural-based adsorbent with high efficacy for the cationic dye methylene blue (MB). A natural-based nanocomposite based on hydroxyapatite (HAp) and hydroxypropyl methylcellulose (HPMC) was selected for this purpose. It was synthesized by the dissolution/reprecipitation method. A film with a homogeneous and smooth surface composed of nanoparticles was prepared from the nanocomposite. HPMC and HAp biopolymers were selected due to their compatibility, biodegradability, and non-toxicity. Total reflectance infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), and calorimetric/thermal gravimetric (DSC/TGA) analysis results revealed the existence of strong physical interaction between the composite components. Scanning electron microscopy (SEM) observations show a composite sheet with a homogenous and smooth surface, indicating excellent compatibility between HPMC and HAp in the composite. The nanocomposite was evaluated as an adsorbent for organic dyes in an aqueous solution. The effects of solution pH, initial MB concentration, composite concentration, and adsorption time on the adsorption efficiency were evaluated. The highest adsorption rate was seen as 52.0 mg of MB/g composite. The adsorption rate reached equilibrium in about 20 min. Fitting of the adsorption data to the Langmuir and Freundlich adsorption models was investigated. Results showed that the adsorption process follows the Langmuir isotherm model. The kinetic study results revealed that the adsorption process was pseudo-second-order. The herein composite is an excellent alternative for use as contemporary industrial-scale adsorbents.

11.
BMC Chem ; 16(1): 43, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35689266

RESUMO

BACKGROUND: Cellulose polymers with multidentate chelating functionalities that have high efficiency for toxic metal ions present in water were designed, synthesized, and analyzed. The synthesis was carried out by reacting microcrystalline cellulose extracted from the solid waste of the olive industry with tert-Butyl acetoacetate (Cell-AA), produced cellulose with ß-ketoester functionality was then reacted with aniline and the amino acid glycine to produce Cell-ß-AN and Cell-ß-GL, respectively. RESULTS: The adsorption efficiency of the three polymers toward Pb(II) and various toxic metal ions present in sewage was evaluated as a function of adsorbent dose, time, temperature, pH value, and initial ion concentration to determine optimum adsorption conditions. The three polymers showed excellent efficiency toward about 20 metal ions present in a sewage sample collected from the sewer. The adsorption process follows the Langmuir adsorption isotherm model with a second-order of adsorption rate, the calculated qe values (2.675, 15.252, 20.856 mg/g) were close to the experimental qe values (2.133, 13.91, 18.786 mg/g) for the three polymers Cell-AA, Cell-ß-AG and Cell-ß-AN, respectively. Molecular Dynamic (MD) and Monte Carlo (MC) simulations were performed on the three polymers complexed with Pb(II). CONCLUSION: The waste material of the olive industry was used as a precursor for making the target cellulose polymers with ß-Amino Ester Pendant Group. The polymer was characterized by SEM, proton NMR, TGA, and FT-IR spectroscopy. The efficacy of adsorption was quantitative for metal ions present in a real sample of wastewater and the efficiency didn't drop even after 7 cycles of use. The results indicate the existence of strong complexation. The thermodynamic study results showed a spontaneous bonding between of Pb(II) and the polymers pendant groups expressed by the negative value of the Gibbs free energy.

12.
Molecules ; 27(4)2022 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-35209201

RESUMO

The need for biodegradable and biocompatible polymers is growing quickly, particularly in the biomedical and environmental industries. Cellulose acetate, a natural polysaccharide, can be taken from plants and modified with polycaprolactone to improve its characteristics for a number of uses, including biomedical applications and food packaging. Cellulose acetate-g-polycaprolactone was prepared by a three-step reaction: First, polymerization of ε-caprolactone via ring-opening polymerization (ROP) reaction using 2-hydroxyethyl methacrylate (HEMA) and functionalization of polycaprolactone(PCL) by introducing NCO on the hydroxyl end of the HEMA-PCL using hexamethyl lenediisocyanate(HDI) were carried out. Then, the NCO-HEMA-PCL was grafted onto cellulose acetate (using the "grafting to" method). The polycaprolactone grafted cellulose acetate was confirmed by FTIR, the thermal characteristics of the copolymers were investigated by DSC and TGA, and the hydrophobicity was analyzed via water CA measurement. Introducing NCO-PCL to cellulose acetate increased the thermal stability. The contact angle of the unreacted PCL was higher than that of cellulose acetate-g-PCL, and it increased when the chain length increased. The CA-g-PCL50, CA-g-PCL100, and CA-g-PCL200 showed very high inhibition zones for all three bacteria tested (E. coli, S. aureus, and P. aeruginosa).


Assuntos
Antibacterianos , Bactérias/crescimento & desenvolvimento , Celulose/análogos & derivados , Embalagem de Alimentos , Poliésteres , Polimerização , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Celulose/síntese química , Celulose/química , Celulose/farmacologia , Poliésteres/síntese química , Poliésteres/química , Poliésteres/farmacologia
13.
Environ Sci Pollut Res Int ; 26(27): 28080-28091, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31363973

RESUMO

A cross-linked cellulose-amine polymer composed of nanocrystalline cellulose and 1,4-pheneylnediamine was synthesized, and its application as an adsorbent of metal ions from wastewater was dementated. The nanocrystalline cellulose was generated from an olive industry solid waste. The cross-linked polymer analysis results of FTIR, NMR, TEM, SEM, and XRD were generated. The adsorption efficiency of the cellulose-amine polymer toward Cu(II) and Pb(II) was investigated as a function of adsorbent dose, temperature, pH, and time. The adsorption parameters that lead to an excellent adsorption efficiency were determined. The polymer also showed an excellent extraction efficiency toward 20 metal ions present in a sewage sample. The various functional groups present on polymer surface such as amino, hydroxyl, and aryl played a crucial role on metal adsorption. Thermodynamic analysis results support the high efficiency of the polymer toward the metal ions. Kinetic study results reveal that the adsorption process fits well with the pseudo-second-order model and the adsorption isotherm follows a Langmuir isotherm model.


Assuntos
Eliminação de Resíduos Líquidos/métodos , Adsorção , Aminas , Celulose/química , Íons/análise , Cinética , Metais Pesados/análise , Polímeros , Temperatura , Termodinâmica , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos
14.
Environ Sci Pollut Res Int ; 25(22): 22060-22074, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29802610

RESUMO

The work shown in this article demonstrate a novel example of converting olive industry solid waste (OISW) into a magnetic cellulose nanocrystalline (MNCs) to serve as selective magnetic sorbents for methylene blue. Olive industry solid waste contains about 40% cellulose. The cellulose was extracted in a powder form from olive industry solid waste by subjecting it to a multistep pulping and bleaching process. The extracted powder cellulose was then converted to nanocrystalline cellulose (NCs) by acid hydrolysis. The NCs were then treated with a solution of FeCl3.6H2O, FeSO4, and H2O by a colloidal suspension method which produced free-flowing porous MNCs. The produced MNCs are characterized by several spectroscopic and analytical techniques such as SEM, TEM, XRD, FTIR VSM, and TGA. The efficiency of the three polymers cellulose powder, NCs, and MNCs toward extracting methylene blue (MB) from water was evaluated. Cellulose powder and NCs showed acceptable tendency for methylene blue. However, MNCs showed excellent extraction efficiency toward MB. The thermodynamic studies revealed a spontaneous adsorption of MB by MNCs at various temperatures. The spontaneous adsorption could be attributed to the electrostatic interaction and H-bonding between MNCs and MB. However, the interaction between cellulose, NCs, and MB is limited to the H-bonding.


Assuntos
Celulose/química , Azul de Metileno/isolamento & purificação , Resíduos Sólidos , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Indústria de Processamento de Alimentos , Magnetismo , Azul de Metileno/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanoestruturas/química , Olea , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Águas Residuárias/química , Poluentes Químicos da Água/química , Difração de Raios X
15.
Carbohydr Polym ; 111: 41-6, 2014 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-25037327

RESUMO

The aim of this work is to develop composite materials with hydroxyapatite (HAp) mineral and organic matrix such as cellulosic polymers. We use cellulose acetate with different percentages, and then inorganic-organic films were fabricated by evaporation of solvent. The composite films were characterized using emission scanning electron microscopy (FEG-SEM), thermo-gravimetric analysis (TGA) and Fourier transform infra-red (FT-IR) spectra. Test results show that these films are uniform and have good ductility. A strong interaction existed between HAp and cellulosic polymers, and the method allows the production of very fine particles size of about 92 nm. We have developed a new chromatographic method for the quantification of bisphenol A (BPA) in samples of baby food. The result of this study demonstrates how to use this type of composite materials to remove pollutants.


Assuntos
Compostos Benzidrílicos/isolamento & purificação , Celulose/análogos & derivados , Durapatita/química , Poluentes Ambientais/isolamento & purificação , Contaminação de Alimentos/análise , Fenóis/isolamento & purificação , Adsorção , Compostos Benzidrílicos/análise , Celulose/química , Poluentes Ambientais/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Fórmulas Infantis/química , Recém-Nascido , Modelos Moleculares , Fenóis/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
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