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1.
Int J Biol Macromol ; 270(Pt 2): 132252, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729503

RESUMO

In this study, we developed a novel nanocomposite by synthesizing zinc (ZnNPs), copper (CuNPs), and silver (AgNPs) nanoparticles using olive leaf extract and incorporating them into a chitosan polymer. This approach combines the biocompatibility of chitosan with the antimicrobial and anticancer properties of metal nanoparticles, enhanced by the phytochemical richness of olive leaf extract. The significance of our research lies in its potential to offer a biodegradable and stable alternative to conventional antibiotics and cancer treatments, particularly in combating multidrug-resistant bacteria and various cancer types. Comprehensive characterization through Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), and Transmission Electron Microscopy (TEM) confirmed the successful synthesis of the nanocomposites, with an average size of ~22.6 nm. Phytochemical analysis highlighted the antioxidant-rich composition of both the olive leaf extract and the nanoparticles themselves. Functionally, the synthesized nanoparticles exhibited potent antimicrobial activity against multidrug-resistant bacterial strains, outperforming traditional antibiotics by inhibiting key resistance genes (ermC, tetX3-q, blaZ, and Ery-msrA). In anticancer assessments, the nanoparticles showed selective cytotoxicity towards cancer cells in a concentration-dependent manner, with CuNPs and AgNPs showing particularly strong anticancer effects, while demonstrating minimal toxicity towards normal cells. ZnNPs were noted for their low cytotoxicity, highlighting the safety profile of these nanoparticles. Further, the nanoparticles induced apoptosis in cancer cells, as evidenced by the modulation of oncogenes (P21, P53, and BCL2), suggesting their therapeutic potential. The findings of our study underscore the versatile applications of these biogenic nanoparticles in developing safer and more effective antimicrobial and anticancer therapies.


Assuntos
Antineoplásicos , Quitosana , Química Verde , Nanopartículas Metálicas , Nanocompostos , Olea , Extratos Vegetais , Folhas de Planta , Quitosana/química , Quitosana/farmacologia , Nanocompostos/química , Olea/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Humanos , Folhas de Planta/química , Nanopartículas Metálicas/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/síntese química , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Prata/química , Prata/farmacologia , Linhagem Celular Tumoral
2.
Environ Res ; 249: 118473, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38354892

RESUMO

The development of a catalyst with a consistent and clearly defined crystal structure is crucial for establishing an efficient catalytic performance system. This study focuses on catalyzing the reduction of nitroarenes to amino-derivatives in an aquatic environment at ambient temperature, employing metallic (Au) and bimetallic (Au-Pd or Au-Ag) nanoparticles loaded on a Ce-BTC metal-organic framework using a facile sol-immobilization approach. Diverse analytical instruments, comprising SEM, TEM, XRD, FT-IR, XPS, TGA, and N2 isotherm, have been utilized to characterize the synthesized catalysts. Among the catalysts that were fabricated, Au-Pd@Ce-BTC displayed the maximum catalytic efficacy, offering a rate constant (kapp) of 0.5841 min-1, conversion percentages reaching 99.7%, and a KAF of 116.8 min-1g-1. Moreover, it exhibited remarkable recyclability over five consecutive cycles. This catalyst offers the advantages of operating under ambient reaction conditions and exhibiting tolerance to a broad range of substrates containing various functional moieties. The mechanistic understanding of nitroarene reduction and the factors contributing to the superior activity of Au-Pd/Ce-BTC are explored through spectroscopic and porosity analyses. Spectroscopic measurements indicate that the elevated Auo and Pdo/Pd2+ ratio, increased surface area, and the synergistic collaboration of the bimetallic NPs are key factors contributing to the heightened activity of Au-Pd/Ce-BTC. These findings hold significant appeal from both an industrial and academic standpoint.


Assuntos
Nanopartículas Metálicas , Nanopartículas Metálicas/química , Catálise , Ouro/química , Estruturas Metalorgânicas/química , Oxirredução , Paládio/química , Cério/química , Poluentes Químicos da Água/química
3.
Int J Nanomedicine ; 19: 1469-1485, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38380146

RESUMO

Background: Nowadays, recycling agricultural waste is of the utmost importance in the world for the production of valuable bioactive compounds and environmental protection. Olive leaf bioactive compounds have a significant potential impact on the pharmaceutical industry. These compounds possess remarkable biological characteristics, including antimicrobial, antiviral, anti-inflammatory, hypoglycemic, and antioxidant properties. Methods: The present study demonstrates a green synthetic approach for the fabrication of nickel oxide nanoparticles (NiO-olive) using aqueous wasted olive leaf extract. Calcination of NiO-olive at 500°C led to the fabrication of pure NiO nanoparticles (NiO-pure). Different techniques, such as thermal gravimetric analysis (TGA), Fourier-transform infrared spectra (FTIR), ultraviolet-visible spectra (UV-Vis), X-ray diffraction (XRD), scanning electron microscopy (SEM) fitted with energy-dispersive X-ray analysis (EDX), and transmission electron microscopy (TEM), were used to characterize both NiO-olive and NiO-pure. The extract and nanoparticles were assessed for antiparasitic activity against adult ticks (Hyalomma dromedarii) and antimicrobial activity against Bacillus cereus, Pseudomonas aeruginosa, Aspergillus niger, and Candida albicans. Results: From XRD, the crystal sizes of NiO-olive and NiO-pure were 32.94 nm and 13.85 nm, respectively. TGA, FTIR, and EDX showed the presence of olive organic residues in NiO-olive and their absence in NiO-pure. SEM and TEM showed an asymmetrical structure of NiO-olive and a regular, semi-spherical structure of NiO-pure. UV-Vis spectra showed surface plasmon resonance of NPs. Antiparasitic activity showed the highest mortality rate of 95% observed at a concentration of 0.06 mg/mL after four days of incubation. The antimicrobial activity showed the largest inhibition zone diameter of 33 ± 0.2 mm against the Candida albicans strain. Conclusion: Nanoparticles of NiO-olive outperformed nanoparticles of NiO-pure and olive leaf extract in both antiparasitic and antimicrobial tests. These findings imply that NiO-olive may be widely used as an eco-friendly and effective antiparasitic and disinfection of sewage.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Olea , Antiparasitários , Nanopartículas Metálicas/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
4.
Polymers (Basel) ; 15(19)2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37836079

RESUMO

Given the rising consumption of plastic products, it is becoming imperative to prioritize the recycling of plastic items as a solution to reducing plastic waste and environmental pollution. In this context, this research focuses on assessing the impact of incorporating rice husk and wood flour into recycled high-density polyethylene (rec-HDPE) to analyze its mechanical properties, flammability, and thermal stability. The combined rec-HDPE content of wood flour and rice husk varied between 0% and 20%. The rec-HDPE content of maleic anhydride grafted polyethylene (MAPE) was fixed at 3%. Mechanical characteristics such as flexural, tensile, and impact strengths were assessed. Cone calorimetry (CC) tests, limited oxygen index (LOI) tests, and horizontal and vertical burning tests were performed to determine the flammability or fire retardancy of these composites. On the other hand, to characterize the thermal characteristics of these composites, thermogravimetric analysis (TGA) was used. To further characterize the fluctuation in these characteristics, scanning electron microscopy (SEM) and infrared spectroscopy (FTIR) studies were carried out. The mechanical characteristics were found to be increased in response to adding rice husk or wood flour. An 8% increase in tensile strength and a 20% increase in elastic modulus enhancement were recorded for a 20% rice husk-added composite. SEM revealed the reason for the variation in tensile properties, based on the extent of agglomeration and the extent of uniform distribution of fillers in rec-HDPE. Following these lines, the 20% rice husk-added composite also showed a maximum increase of around 6% in its flexural strength and a maximum increase of 50% in its flexural modulus. A decrease in impact strength was recorded for rice husk and wood flour-reinforced composites, compared with unreinforced rec-HDPE. Hybrid composites displayed a lack of mechanical strength due to changes in their nature. FTIR tests were performed for a much more elaborate analysis to confirm these results. Twenty percent of rice husk-added rec-HDPE displayed the best thermal properties that were tested, based on TGA and derivative thermogravimetric (DTG) analysis. This 20% composite also displayed the best fire-retardancy characteristics according to UL 94 tests, cone calorimetry tests, and limited oxygen index tests, due to the barrier created by the silica protective layer. These tests demonstrated that the incorporation of both fillers-rice husk and wood flour-effectively enhanced the thermal, mechanical, and fire-retardant attributes of recycled HDPE.

5.
Environ Res ; 234: 116587, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37423355

RESUMO

The outstanding properties of nanofiber composites have made them a popular choice for various structural applications. Recently, there has been a growing interest in using electrospun nanofibers as reinforcement agents, which possess exceptional properties that can enhance the performance of these composites. Herein, TiO2-graphene oxide (GO) nanocomposite incorporated into polyacrylonitrile (PAN)/cellulose acetate (CA) nanofibers were fabricated by an effortless electrospinning technique. The chemical and structural characteristics of the resulting electrospun TiO2-GO nanofibers were examined employing diverse techniques such as XRD, FTIR, XPS, TGA, mechanical properties, and FESEM. Remediation of organic contaminants and organic transformation reactions with electrospun TiO2-GO nanofibers were performed. The results indicated that the incorporation of TiO2-GO with various TiO2/GO ratios did not affect the molecular structure of PAN-CA. Still, they did significantly increase the mean fiber diameter (234-467 nm) and the mechanical properties of the nanofibers comprising UTS, elongation, Young's modulus, and toughness compared to PAN-CA. From various ratios of TiO2/GO (0.01TiO2/0.005GO and 0.005TiO2/0.01GO) in the electrospun NFs, the nanofiber containing a high content of TiO2 showed over 97% of the initial MB dyes were degraded after 120 min of visible light exposure and the same nanofibers also, achieved 96% nitrophenol conversion to aminophenol in just 10 min with activity factor kAF value of 47.7 g-1min-1. These findings illustrate the promise of TiO2-GO/PAN-CA nanofibers for use in various structural applications, particularly in the remediation of organic contaminants from water and organic transformation reactions.


Assuntos
Nanofibras , Nitrofenóis
6.
Nanomaterials (Basel) ; 13(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37446472

RESUMO

Layered double hydroxides (LDHs) present exciting possibilities across various industries, ranging from catalytic applications to water remediation. By immobilizing nanoparticles, LDHs' characteristics and functionality can be enhanced, allowing for synergetic interactions that further expand their potential uses. A simple chemical method was developed to produce well-dispersed Pd-Cu NPs on a Co-Cr LDH support using a combination of in situ coprecipitation/hydrothermal and sol-immobilization techniques. The Pd-Cu@Co-Cr LDH catalysts was obtained, showing its catalytic activity in promoting the aerobic oxidation of alcohols and enabling the reduction of nitro-compounds through NaBH4 mediation. The physicochemical properties of the prepared catalyst were comprehensively investigated utilizing a range of analytical techniques, comprising FTIR, XRD, XPS, TGA, nitrogen adsorption isotherm, FESEM, and HRTEM-EDX. The findings showed the significance of immobilizing the bimetallic Pd-Cu nanoparticles on the Co-Cr LDH via an exceptional performance in the aerobic oxidation of benzyl alcohol (16% conversion, 99.9% selectivity to benzaldehyde) and the reduction of nitrobenzene (98.2% conversion, rate constant of 0.0921 min-1). The improved catalytic efficacy in benzyl alcohol oxidation and nitrobenzene reduction on the Pd-Cu@Co-Cr LDH catalyst is attributed to the uniform distribution and small size of the Pd-Cu NPs as active sites on the Co-Cr LDH surface. The prepared catalyst demonstrated exceptional stability during repeated runs. This study paves the way for multiple opportunities in tailoring, producing, and precisely controlling catalysts for various organic transformation reactions.

7.
Molecules ; 28(13)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37446822

RESUMO

This work addresses two research topics: the first concerns the specific/sensitive trapping of hydroxyl radicals (•OH), and the second concerns the efficacy of encapsulating natural antioxidants, potentially lengthening their preservation activity. For context, nano-titania was solar-irradiated to produce •OH, which was spectrofluorimetrically assessed, based on the selective aromatic hydroxylation of the non-fluorescent sodium terephthalate to 2-hydroxyterephthalate fluorophore. Fluorescence intensity is proportional to generated •OH. Thus, a simple/rapid indirect method was utilized to assess •OH precisely. Accordingly, novel photoluminescent system is outlined in order to assess the scavenging potentiality of •OH in date seed oil (DSO) in both its pure and encapsulated formulations (ECP-DSO), i.e., when fresh and 5 months after extraction and encapsulation, respectively. With the addition of 80 µg/mL DSO or ECP-DSO, the efficacy of •OH scavenging amounted to 25.12 and 63.39%, which increased to 68.65 and 92.72% when 200 µg/mL DSO or ECP-DSO, respectively, was added. Moreover, the IC50 of DSO and ECP-DSO is 136.6 and 62.1 µg/mL, respectively. Furthermore, DSO and ECP-DSO decreased the kinetics for producing •OH by ≈20 and 40%, respectively, relative to •OH generated in the absence of antioxidant. This demonstrates the benefits of encapsulation on the preservation activity of natural antioxidants, even after five months after extraction, in terms of its interesting activity when compared to synthetic antioxidants. The developed fluorimetric •OH probing upgrades antioxidant medicines, thus paving the way for theoretical/practical insights on mechanistic hydroxyl radical-damaging biology.


Assuntos
Antioxidantes , Radical Hidroxila , Antioxidantes/farmacologia , Espectrometria de Fluorescência , Sementes , Extratos Vegetais , Sequestradores de Radicais Livres
8.
RSC Adv ; 13(23): 15575-15585, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37228682

RESUMO

The layered structures of tungsten disulfide (WS2) and molybdenum tungsten disulfide (MoWS2) are considered as the most promising electrode materials for energy storage devices. Herein, MS (magnetron sputtering) is required for the deposition of WS2 and MoWS2 on the surface of the current collector to attain an optimized layer thickness. The structural morphology and topological behavior of the sputtered material were examined via X-ray diffraction and atomic force microscopy. Three-electrode assembly was used to start the electrochemical investigations to identify the most optimal and effective sample among WS2 and MoWS2. CV (cyclic voltammetry), GCD (galvanostatic charging discharging), and EIS (electro-impedance spectroscopy) techniques were employed to analyze the samples. After preparing WS2 with optimized thickness as the superior performing sample, a hybrid device was designed as WS2//AC (activated carbon). With a remarkable cyclic stability of 97% after 3000 continuous cycles, the hybrid supercapacitor generated a maximum energy density (Es) value of 42.5 W h kg-1 and 4250 W kg-1 of power density (Ps). Besides, the capacitive and diffusive contribution during the charge-discharge process and b-values were calculated by Dunn's model, which lay in the 0.5-1.0 range and the fabricated WS2 hybrid device was found to have a hybrid nature. The outstanding outcomes of WS2//AC make it suitable for future energy storage applications.

9.
Environ Res ; 231(Pt 3): 116259, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37247654

RESUMO

We report a facile approach to synthesize Pd-Cu nanoparticles immobilized on a Noria-GO nanocomposite for efficient nitrophenol reduction. The unique architecture of the Noria and the hydrophilic nature of GO contribute to the improved performance and structure of the resulting nanocomposite. The simple sol-immobilization approach employed NaBH4 as a reductant and polyvinyl alcohol as a capping agent to evenly decorate small Pd-Cu nanoparticles with a diameter of 1.4 nm on the Noria-GO surface. The prepared Pd-Cu@Noria-GO nanocomposite was utilized as a nanocatalyst in converting of nitrophenol to aminophenol using NaBH4 solution. Our Pd-Cu@Noria-GO nanocomposite exhibited superior catalytic efficacy with large conversion percentages, Kapp, and KAF values of 95%, 0.225 min-1, and 225 min-1g-1, respectively. X-ray photoemission spectroscopy confirmed the oxidation state of the prepared nanoparticles, and TEM findings demonstrated the homogenous decoration of Pd-Cu NPs on the Noria-GO surface. Additionally, the durability of the Pd-Cu@Noria-GO nanocomposite shown its potential as a robust and promising material for remediating organic contaminants. Our results indicate that Pd-Cu@Noria-GO nanocomposite can be an effective and sustainable approach for mitigating the hazards associated with nitrophenols.


Assuntos
Nanocompostos , Nanopartículas , Nitrofenóis , Oxirredução , Nanocompostos/química , Substâncias Redutoras , Catálise
10.
Polymers (Basel) ; 15(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37177334

RESUMO

A simple approach for synthesizing a highly adsorbent composite was described for the uptake of heavy metal ions from wastewater. A simple approach for synthesizing a highly adsorbent composite was also described for the elimination of heavy metal ions from contaminated water. The nanocomposite was synthesized via a polymer grafting of chitosan on the activated carbon surface, followed by a stacking process with the layers of montmorillonite clay. The spectroscopic analyses were exploited to confirm the composite structure of the prepared materials. Various adsorption parameters, such as pH, initial concentration, and adsorption time, were assessed. The results showed that the adsorption capacity of the composite for Pb2+ ions increased as the pH increased until it reached pH 5.5. The maximum adsorption capacity was observed at an initial Pb2+ level of 20 mg/L and a contact time of 150 min. Kinetic models were evaluated, and the pseudo second-order model showed the best match. The adsorption isotherm data were processed by fitting the model with different isotherm behaviors, and the Langmuir isotherm was found to be the most suitable for the system. The maximum adsorption capacity for Pb2+ ion on the MMT/CS/AC composite was found to be 50 mg/g at pH 5.5. Furthermore, the composite maintained a high adsorption capability of 85% for five adsorption-desorption cycles. Overall, this composite is envisioned as an addition to the market of wastewater remediation technology due to its chemical structure, which provides influential functional groups for wastewater treatment.

11.
J Environ Manage ; 332: 117351, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36731407

RESUMO

In this work, CdS quantum dots (QDs) were successfully confined in polysulfone membrane (PSM) to develop a photoactive membrane under solar illumination that was suited in wastewater remediating system. The CdS@PSM membranes were prepared using the nonsolvent induced phase separation (NIPS) approach. Optical measurements show the confinement of CdS quantum dots (QDs) in the PS matrix within the narrowest band gap (2.41 eV) at 5 wt% loading. PS has two strong emission peaks at 411 and 432 nm due to photoelectron-hole recombination on pure PSM's surface. Adding 1 wt% CdS QDs to PSM reduced the earlier peak and blue-shifted the latter, within the appearance of three emission peaks attributed to the near band-edge emission of confined CdS QDs. Overloading CdS reduced all emission peaks. Moreover, fluorimetric monitoring of •OH radicals indicates that PSM produces the least amount of photogenerated •OH radicals while CdS@PSM(5 wt%) achieved the highest productivity. Examining the developed membranes in detoxifying methylene blue (MB) from aqueous solution of natural pH 8.1 showed weak adsorption in dark over 90 min of contact while switching to solar illumination significantly photodegrade MB where the degradation efficiency starts from 49% for pure PSM to 79% for CdS@PSM(5 wt%). Influence of pH was found crucial on photodegradation efficacy. Acidic pH 3 showed the weakest photodegradation efficacy, while the alkaline pH 12 was 18.88 times more effective. The used CdS@PSM (5 wt%) was successfully photo-renovated by soaking in 10 mL of NaOH solution under Solar illumination for 15 min to be used in 4 consecutive photodegradation cycles with insignificant decrease in efficacy. These findings are promising and could lead to a high-efficiency, sustainable photocatalytic suite.


Assuntos
Pontos Quânticos , Águas Residuárias , Luz Solar , Polímeros
12.
Biomed Chromatogr ; 37(5): e5612, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36849127

RESUMO

The mixture of hyoscine N-butyl bromide (HBB) and ketoprofen (KTP) is commonly used for the handling of abdominal spasms and pain relief. There are two challenges that restrict the simultaneous assessment of HBB and KTP in biological fluids and pharmaceuticals. The first issue is the difficulty of elution of HBB and the second one is the presence of KTP as a racemic mixture in all pharmaceutical formulations, which obscures its appearance as a single peak. An ultrasensitive and highly efficient liquid chromatography-mass/mass spectrometric (LC-MS/MS) method is designed and validated for the first concurrent assessment of HBB and KTP in spiked human serum and urine, and pharmaceutical formulations. The estimated linearity ranges for HBB and KTP were respectively, 0.5-500 and 0.05-500 ng/ml, with excellent correlation coefficients. Validation results showed that the value of relative standard deviations were <2% for HBB and KTP. The mean extraction recoveries for HBB and KTP were, respectively, 91.04 and 97.83% in Spasmofen® ampoules; 95.89 and 97.00% in spiked serum; and 97.31 and 95.63% in spiked urine. The presented innovative chromatographic approach was utilized for the measurement of trace amounts of coexisting pharmaceuticals in pharmacokinetics studies and routine therapeutic medication monitoring.


Assuntos
Cetoprofeno , Humanos , Cetoprofeno/química , Brometo de Butilescopolamônio , Escopolamina , Cromatografia Líquida , Espectrometria de Massas em Tandem , Preparações Farmacêuticas
13.
Polymers (Basel) ; 14(24)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36559828

RESUMO

Nanofiltration membranes were successfully created using multi-walled carbon nanotubes (MWCNTs) and MWCNTs modified with amine (MWCNT-NH2) and carboxylic groups (MWCNT-COOH). Chitosan (CHIT) and chitosan−glutaraldehyde (CHIT-G) were utilized as dispersants. Sonication, SEM, and contact angle were used to characterize the as-prepared membranes. The results revealed that the type of multi-walled carbon nanotubes (MWCNT, MWCNT-COOH and MWCNT-NH2) used as the top layer had a significant impact on membrane characteristics. The lowest contact angle was 38.6 ± 8.5 for the chitosan-G/MWCNT-COOH membrane. The surface morphology of membranes changed when carbon with carboxylic or amine groups was introduced. In addition, water permeability was greater for CHIT-G/MWCNT-COOH and CHIT-G/MWCNT-NH2 membranes. The CHIT-G/MWCNT-COOH membrane had the highest water permeability (5.64 ± 0.27 L m−2 h−1 bar−1). The findings also revealed that for all membranes, the rejection of inorganic salts was in the order R(NaCl) > R(MgSO4).

14.
Molecules ; 27(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36234905

RESUMO

An appropriate and efficient Q-tube-assisted ammonium acetate-mediated protocol for the assembly of the hitherto unreported 5-arylazopyrazolo[3,4-b]pyridines was demonstrated. This methodology comprises the cyclocondensation reaction of 5-amino-2-phenyl-4H-pyrazol-3-one with an assortment of arylhydrazonals in an NH4OAc/AcOH buffer solution operating a Q-tube reactor. This versatile protocol exhibited several outstanding merits: easy work-up, mild conditions, scalability, broad substrate scope, safety (the Q-tube kit is simply for pressing and sealing), and a high atom economy. Consequently, performing such reactions under elevated pressures and utilizing the Q-tube reactor seemed preferable for achieving the required products in comparison to the conventional conditions. Diverse spectroscopic methods and X-ray single-crystal techniques were applied to confirm the proposed structure of the targeted compounds.


Assuntos
Piridinas , Catálise , Técnicas de Química Sintética , Piridinas/química
15.
Pharmaceuticals (Basel) ; 15(9)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36145355

RESUMO

In this study new sulphamethoxazole derivatives (S1-S4, S6-S12, and S14-S22) were designed and synthesized and their structures were fully characterized and validated using NMR, mass, and IR spectroscopy, as well as elemental analyses. All new derivatives (S1-S22) were assayed against human carbonic anhydrase (hCAs IX and XII) for their inhibitory activities. hCAs IX and XII were chosen due to the fact that CAIX expression is recognized as a hypoxia marker with a poor prognosis in breast cancer. When compared to Dorzolamide HCl as a standard reference, derivatives S2, S3, S8, S9, and S15 had the most effective inhibition with low IC50 values. The active compounds were further evaluated against hCAs I and II inhibitory activity and compounds S8, S9 and S15 showed the least inhibitory effect compared to the reference standard, acetazolamide, indicating that their effect in normal cells is the lowest. Cell viability tests for the selected compounds were carried out on MCF7 (normoxia and hypoxia) and on the normal breast cell line (MCF10a) with Staurosporine as a standard. The results showed that compound S15 had a highly potent cytotoxic effect. Furthermore, cell cycle analysis results showed that compound S15 triggered cell cycle arrest and apoptosis in G1/S of MCF7 cancer cells. Finally, molecular docking was performed to point out the possible explanation for the vital structural features and key-interactions exerted by our ligands with hCAs IX and XII that might share additional designs and highlight possible leads for a hopeful anticancer agent. Consequently, sulphamethoxazole Derivative S15 could be the potential lead for emerging selective cytotoxic compounds directing h CAs IX and XII.

16.
Int J Biol Macromol ; 220: 1241-1252, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36030975

RESUMO

Green technology is a scientific movement seeking to eliminate industrial chemicals and replace them with natural products by valorizing natural resources or biological waste. In this work, we present the extraction of cellulose from rice straw and chemically modified water-dispersible cellulose (methylcellulose) by performing a methylation process. The methylcellulose is chemically bonded to N-[3-(trimethoxysilyl)propyl]ethylenediamine, and (3-aminopropyl)triethoxysilane compounds to produce a cellulose-organosilane hybrid. The prepared compounds were studied with appropriate techniques such as 1H NMR, XRD, FTIR, TGA, Raman spectroscopy, FE-SEM, and AFM. The prepared materials were used as corrosion inhibitors of steel in 1 N H2SO4 for studies of potentiodynamic polarization measurements and electrochemical impedance spectroscopy. The materials were also studied as antibacterial agents. The results indicate the successful use of a modified extracted cellulose hybrid in the corrosion field and as an antibacterial agent. Quantum chemical assessments based on density functional theory (DFT) of the trimethoxysilyl propylamine and dimethoxymethylsilyl propylethylenediamine grafted methylcellulose were calculated. The results obtained showed the agreement of the theoretical data with the experimental data.


Assuntos
Produtos Biológicos , Compostos de Organossilício , Oryza , Antibacterianos/farmacologia , Celulose , Corrosão , Etilenodiaminas , Metilcelulose , Propilaminas , Aço/química , Água
17.
Plants (Basel) ; 11(14)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35890504

RESUMO

Origanum majoranum L. is a Lamiaceae medicinal plant with culinary and ethnomedical applications. Its biological and phytochemical profiles have been extensively researched. Accordingly, this study aimed to investigate the chemical composition and the antibacterial and antioxidant properties of O. majoranum high features, as well as to search for techniques for activity optimization. A metabolomics study of the crude extract of O. majoranum using liquid chromatography-high-resolution electrospray ionization mass spectrometry (LC ± HR ± ESI ± MS) was conducted. Five fractions (petroleum ether, dichloromethane, ethyl acetate, n-butanol, and aqueous) were derived from the total extract of the aerial parts. Different chromatographic methods and NMR analysis were utilized to purify and identify the isolated phenolics (high features). Moreover, the antimicrobial, antibiofilm, and antioxidant activity of phenolics were performed. Results showed that metabolomic profiling of the crude extract of O. majoranum aerial parts revealed the presence of a variety of phytochemicals, predominantly phenolics, resulting in the isolation and identification of seven high-feature compounds comprising two phenolic acids, rosmarinic and caffeic acids, one phenolic diterpene, 7-methoxyepirosmanol, in addition to four flavonoids, quercetin, hesperitin, hesperidin, and luteolin. On the other hand, 7-methoxyepirosmanol (OM1) displayed the most antimicrobial and antioxidant potential. Such a phenolic principal activity improvement seems to be established after loading on gold nanoparticles.

18.
Food Chem ; 389: 133050, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35483301

RESUMO

A new method based on spectrophotometry combined with graphitic digestion was developed for quantitative assessment of phosphate in frozen and chilled chicken meat. Digestion reagents comprising HNO3 (conc.) & H2SO4 (conc.) and HNO3 (5 M) & H2SO4 (conc.) were found to have optimal composition, affording similar recovery values of 100% and 99%, respectively, with excellent linearity (R2 > 0.999) and good limit of detection (LOD = 0.032 mg/L) and limit of quantification (LOQ = 0.10 mg/L), whereas other reagents offered lower recoveries (0-1.73%). Phosphate was found in concentrations of 3.38-5.90 g/kg and 3.96-26.94 g/kg in frozen and chilled chicken, respectively. Chilled chicken contained higher amounts of phosphate (>20 g/kg) than recommended by the European Commission (EC, 5 g/kg), either alone or in a mixture of processed meat products. This method is simple, cost-effective, and can be used as an alternative for analyzing phosphate in various samples comprising a similar matrix.


Assuntos
Galinhas , Grafite , Animais , Digestão , Aditivos Alimentares , Fosfatos , Espectrofotometria
19.
Drug Chem Toxicol ; 45(1): 127-132, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31505969

RESUMO

In this work, we developed a simple spectrophotometric strategy for BrO3- ions determination as a major water disinfection constituents in the mice's liver tissues by using pararosaniline (PRA). Mice were divided into seven main groups (6 doses): lowest dose KBrO3 (G1 0.01 mg L-1, G2 0.025 mg L-1 and G3 0.1 mg L-1), highest dose KBrO3 (G4 1 mg L-1, G5 10 mg·L-1 and G6 30 mg L-1) and control. All these groups maintained a dose-specific feeding for one month, just before the bromate assessment in mice's liver samples. The results revealed that groups of exposure to lower doses of drinking water did not detect the presence of BrO3- accumulated in the liver tissue during the study period (1-2 months). While, the BrO3- was detected in higher dosages for samples analyzed in first, second, third, fourth and fifth weeks (W1, W2, W3, W4, and W5). These results confirmed that the higher BrO3- dosages (1, 10, and 30 mg L-1) were fatal if introduced in drinking water and could accumulate in the liver tissues both for mice and for human. Detection the accuracy of the method for recovery of bromate ions in liver samples (N = 5) was found to be more than 95%. Relative standard deviations (RSDs) were found to be less than 2.0% confirming the reproducibility of the assay technique.


Assuntos
Bromatos , Fígado , Administração Oral , Animais , Bromatos/toxicidade , Masculino , Camundongos , Reprodutibilidade dos Testes
20.
Pharmaceuticals (Basel) ; 13(11)2020 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-33266462

RESUMO

Isothiazolinones methylisothiazolinone (MI) and methylchloroisothiazolinone (MCI), and parabens methylparaben (MP), ethylparaben (EP), propylparaben (PP) and butylparaben (BP) are the most common synthetic preservatives. They are all known to be potential skin allergens that lead to contact dermatitis. Thus, the identification of these unsafe chemicals in cosmetic products is of high importance. In the present study, solid-phase extraction (SPE) based on HyperSep reversed-phase C8/benzene sulfonic acid ion exchanger (HyperSep C8/BSAIE) and Sep-Pak C18 sorbents, and ultra-high performance liquid chromatography/diode array detector (UHPLC/DAD) were optimized for the simultaneous determination of MI, MCI, MP, EP, PP and BP in cosmetic products. HyperSep C8/BSAIE and UHPLC/DAD with the eluting solvent mixture (acetonitrile/methanol, 2:1, v/v) and detection wavelength (255 nm) were found to be the optimal conditions, respectively. The method illustrates the excellent linearity range (0.008-20 µg/mL) with coefficient of determination (R2, 0.997-0.999), limits of detection (LOD, 0.001-0.002 µg/mL), precision in terms of relative standard deviation (RSD < 3%, intra-day and <6%, inter-day) when examining a standard mixture at low (0.07 µg/mL), medium (3 µg/mL) and high (15 µg/mL) concentrations. A total of 31 cosmetic samples were studied, achieving concentrations (MI, not detected (nd)-0.89 µg/g), (MCI, nd-0.62 µg/g), (MP, nd-6.53 µg/g), (EP, nd-0.90 µg/g), (PP, nd-9.69 µg/g) and (BP, nd-17.80 µg/g). Recovery values ranged from 92.33 to 101.43% depending on the types of sample. To our knowledge, this is the first specific method which covers the theme and describes background amounts of such preservatives in cosmetics.

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