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1.
Int J Parasitol Drugs Drug Resist ; 24: 100531, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484645

RESUMO

Leishmaniasis and Chagas disease are parasitic infections that affect millions of people worldwide, producing thousands of deaths per year. The current treatments against these pathologies are not totally effective and produce some side effects in the patients. Acrylonitrile derivatives are a group of compounds that have shown activity against these two diseases. In this work, four novels synthetic acrylonitriles were evaluated against the intracellular form and extracellular forms of L. amazonensis and T. cruzi. The compounds 2 and 3 demonstrate to have good selectivity indexes against both parasites, specifically the compound 3 against the amastigote form (SI = 6 against L. amazonensis and SI = 7.4 against T. cruzi). In addition, the parasites treated with these two compounds demonstrate to produce a programmed cell death, since they were positive for the events studied related to this type of death, including chromatin condensation, accumulation of reactive oxygen species and alteration of the mitochondrial membrane potential. In conclusion, this work confirms that acrylonitriles is a source of possible new compounds against kinetoplastids, however, more studies are needed to corroborate this activity.


Assuntos
Acrilonitrila , Antiprotozoários , Doença de Chagas , Leishmania mexicana , Trypanosoma cruzi , Humanos , Antiprotozoários/farmacologia , Acrilonitrila/farmacologia , Acrilonitrila/uso terapêutico , Doença de Chagas/tratamento farmacológico , Morte Celular
2.
Environ Pollut ; 346: 123601, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38373624

RESUMO

The pesticide application method is one of the important factors affecting its effectiveness and residues, and the risk of pesticides to non-target organisms. To elucidate the effect of application methods on the efficacy and residue of cyenopyrafen, and the toxic effects on pollinators honeybees in strawberry cultivation, the efficacy and residual behavior of cyenopyrafen were investigated using foliar spray and backward leaf spray in field trials. The results showed that the initial deposition of cyenopyrafen using backward leaf spray on target leaves reached 5.06-9.81 mg/kg at the dose of 67.5-101.25 g a.i./ha, which was higher than that using foliar spray (2.62-3.71 mg/kg). The half-lives of cyenopyrafen in leaves for foliar and backward leaf spray was 2.3-3.3 and 5.3-5.9 d, respectively. The residues (10 d) of cyenopyrafen in leaves after backward leaf spray was 1.41-3.02 mg/kg, which was higher than that after foliar spraying (0.25-0.37 mg/kg). It is the main reason for the better efficacy after backward leaf spray. However, the residues (10 d) in strawberry after backward leaf spray and foliar spray was 0.04-0.10 and < 0.01 mg/kg, which were well below the established maximum residue levels of cyenopyrafen in Japan and South Korea for food safety. To further investigate the effects of cyenopyrafen residues after backward leaf spray application on pollinator honeybees, sublethal effects of cyenopyrafen on honeybees were studied. The results indicated a significant inhibition in the detoxification metabolic enzymes of honeybees under continuous exposure of cyenopyrafen (0.54 and 5.4 mg/L) over 8 d. The cyenopyrafen exposure also alters the composition of honeybee gut microbiota, such as increasing the relative abundance of Rhizobiales and decreasing the relative abundance of Acetobacterales. The comprehensive data on cyenopyrafen provide basic theoretical for environmental and ecological risk assessment, while backward leaf spray proved to be effective and safe for strawberry cultivation.


Assuntos
Acrilonitrila/análogos & derivados , Fragaria , Praguicidas , Abelhas , Animais , Pirazóis
3.
Int Immunopharmacol ; 130: 111737, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38401465

RESUMO

Combined allergic rhinitis and asthma syndrome (CARAS) is an airway-type 2 immune response with a profuse inflammatory process widely affecting the world population. Due to the compromise of quality of life and the lack of specific pharmacotherapy, the search for new molecules becomes relevant. This study aimed to evaluate the effectiveness of the Morita-Bailys-Hillman adduct (CISACN) treatment in the CARAS experimental model. Female BALB/c mice were ovalbumin (OVA) -sensitized and -challenged and treated with CISACN. The treatment decreased the eosinophil migration to the nasal and lung cavities and tissues and the goblet cell hyperplasia/hypertrophy, attenuated airway hyperactivity by reducing the hyperplasia/hypertrophy of the smooth muscle and the extracellular matrix's thickness. Also, the treatment reduced the clinical signs of rhinitis as nasal rubbing and sneezing in a histamine-induced nasal hyperreactivity assay. The immunomodulatory effect of CISACN was by reducing OVA-specific IgE serum level, and IL-33, IL-4, IL-13, and TGF-ß production, dependent on IFN-γ increase. Furthermore, the effect of CISACN on lung granulocytes was by decreasing the p-p38MAPK/p65NF-κB signaling pathway. Indeed, CISACN reduced the p38MAPK and p65NF-κB activation. These data demonstrated the anti-inflammatory and immunomodulatory effects of the CISACN with scientific support to become a pharmacological tool to treat airway inflammatory diseases.


Assuntos
Acrilonitrila , Asma , Rinite Alérgica , Animais , Feminino , Camundongos , Acrilonitrila/administração & dosagem , Asma/tratamento farmacológico , Asma/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Hiperplasia , Hipertrofia , Imunidade , Inflamação/tratamento farmacológico , Interleucina-4/farmacologia , Pulmão , Camundongos Endogâmicos BALB C , Ovalbumina , Qualidade de Vida , Rinite Alérgica/tratamento farmacológico , Células Th2
4.
J Chromatogr A ; 1719: 464740, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38401373

RESUMO

Desktop 3D printers that operate by the fused deposition modeling (FDM) mechanism are known to release numerous hazardous volatile organic compounds (VOCs) during printing, including some with potential carcinogenic effects. Operating in a similar manner to FDM 3D printers, 3D pens have gained popularity recently from their ability to allow users to effortlessly draw in the air or create various 3D printed shapes while handling the device like a pen. In contrast to numerous modern 3D printers, 3D pens lack their own ventilation systems and are often used in settings with minimum airflow. Their operation makes users more vulnerable to VOC emissions, as the released VOCs are likely to be in the breathing zone. Consequently, monitoring VOCs released during the use of 3D pens is crucial. In this study, VOCs liberated while extruding acrylonitrile butadiene styrene (ABS) filaments from a 3D pen were measured by solid-phase microextraction (SPME) combined with gas chromatography/mass spectrometry (GC/MS). SPME was investigated using the traditional fiber and Arrow geometries with the DVB/Carbon WR/PDMS sorbent while four different brands of ABS filaments-Amazon Basics, Gizmodork, Mynt 3D, and Novamaker-were used with the 3D pen. Heatmap analysis showed differentiation among these brands based on the liberated VOCs. The nozzle temperature and printing speed were found to affect the number and amount of released VOCs. This study goes a step further and presents for the first time a comparison between 3D pen and a desktop 3D printer based on liberated VOCs. Interestingly, the findings reveal that the 3D pen releases a greater number and amount of VOCs compared to the printer. The amounts of liberated VOCs, as indicated by the corresponding chromatographic peak areas, were found to be 1.4 to 62.6 times higher for the 3D pen compared to the 3D printer when using SPME Arrow.


Assuntos
Acrilonitrila , Butadienos , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Microextração em Fase Sólida/métodos , Impressão Tridimensional , Estireno
5.
Chemosphere ; 351: 141191, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218238

RESUMO

Seawater reserves about 4.5 billion tons of uranium, if properly extracted, could be a sustainable green energy resource for hundreds of years, alternating its limited terrestrial ore and reducing the CO2 emitted from fossil fuels. The current seawater uranium adsorbents suffer neither economically viable nor adsorption efficiency, requiring more development to harvest satisfactorily uranium from seawater. Amidoxime-based fibrous adsorbents are the most promising adsorbents of seawater uranium due to abundant chelating sites. However, they suffer from severe shrinkage and stiffness once they dry, losing porous architecture and mechanical properties. Herein, an economical and scalable two-nozzle electrospinning technology was applied to produce poly amidoxime nanofibers (PAO NFs) supported by Poly acrylonitrile nanofibers (PAN NFs) as composite PAO/PAN nanofibrous mats with high structure stability. These PAO/PAN mats, with rapid wettability and excellent mechanical strength, show promising uranium adsorption capacities of 369.8 mg/g at seawater pH level, much higher than PAO and PAN NFs. The uranium adsorption capacity of the PAO/PAN mat reached 5.16 mg/g after 7 days of circulating (10 ppm uranium) spiked natural seawater. Importantly, the composite mat maintained its fibrous structure after five adsorption-desorption cycles with more than 80 % of its adsorption capacity, confirming its recyclability and stability. Therefore, the composite PAO/PAN mat fulfills the basic requirements for effectively and economically trapping uranium from seawater, which could be a matrix for further development.


Assuntos
Acrilonitrila , Nanofibras , Oximas , Urânio , Urânio/química , Nanofibras/química , Água do Mar/química , Adsorção
6.
Methods Mol Biol ; 2741: 273-287, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38217659

RESUMO

Regulatory RNAs, as well as many RNA families, contain chemically modified nucleotides, including pseudouridines (ψ). To map nucleotide modifications, approaches based on enzymatic digestion of RNA followed by nano liquid chromatography-tandem mass spectrometry (nanoLC-MS/MS) analysis were implemented several years ago. However, detection of ψ by mass spectrometry (MS) is challenging as ψ exhibits the same mass as uridine. Thus, a chemical labeling strategy using acrylonitrile was developed to detect this mass-silent modification. Acrylonitrile reacts specifically to ψ to form 1-cyanoethylpseudouridine (Ceψ), resulting in a mass shift of ψ detectable by MS. Here, a protocol detailing the steps from the purification of RNA by polyacrylamide gel electrophoresis, including in-gel labeling of ψ, to MS data interpretation to map ψ and other modifications is proposed. To demonstrate its efficiency, the protocol was applied to bacterial regulatory RNAs from E. coli: 6S RNA and transfer-messenger RNA (tmRNA, also known as 10Sa RNA). Moreover, ribonuclease P (RNase P) was also mapped using this approach. This method enabled the detection of several ψ at single nucleotide resolution.


Assuntos
Acrilonitrila , Pseudouridina , Humanos , Pseudouridina/genética , Espectrometria de Massas em Tandem , Escherichia coli/genética , Escherichia coli/metabolismo , RNA , RNA Bacteriano/metabolismo , Nucleotídeos , Processamento Pós-Transcricional do RNA , RNA de Transferência/genética
7.
Int J Mol Sci ; 25(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38279241

RESUMO

We previously discovered WS-6 as a new antidepressant in correlation to its function of stimulating neurogenesis. Herein, several different scaffolds (stilbene, 1,3-diphenyl 1-propene, 1,3-diphenyl 2-propene, 1,2-diphenyl acrylo-1-nitrile, 1,2-diphenyl acrylo-2-nitrile, 1,3-diphenyl trimethylamine), further varied through substitutions of twelve amide substituents plus the addition of a methylene unit and an inverted amide, were examined to elucidate the SARs for promoting adult rat neurogenesis. Most of the compounds could stimulate proliferation of progenitors, but just a few chemicals possessing a specific structural profile, exemplified by diphenyl acrylonitrile 29b, 32a, and 32b, showed better activity than the clinical drug NSI-189 in promoting newborn cells differentiation into mature neurons. The most potent diphenyl acrylonitrile 32b had an excellent brain AUC to plasma AUC ratio (B/P = 1.6), suggesting its potential for further development as a new lead.


Assuntos
Acrilonitrila , Alcenos , Compostos de Bifenilo , Ratos , Animais , Acrilonitrila/farmacologia , Neurogênese , Hipocampo , Nitrilas/farmacologia , Amidas
8.
Macromol Rapid Commun ; 45(1): e2300271, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37400426

RESUMO

A poly (3,6-bis(thiophen-2-yl)-2,5-bis(2-decyltetradecyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione-co-(2,3-bis(phenyl)acrylonitrile)) (PDPADPP) copolymer, composed of diketopyrrolopyrrole (DPP) and a cyano (nitrile) group with a vinylene spacer linking two benzene rings, is synthesized via a palladium-catalyzed Suzuki coupling reaction. The electrical performance of PDPADPP in organic field-effect transistors (OFETs) and circuits is investigated. The OFETs based on PDPADPP exhibit typical ambipolar transport characteristics, with the as-cast OFETs demonstrating low field-effect hole and electron mobility values of 0.016 and 0.004 cm2  V-1  s-1 , respectively. However, after thermal annealing at 240 °C, the OFETs exhibit improved transport characteristics with highly balanced ambipolar transport, showing average hole and electron mobility values of 0.065 and 0.116 cm2  V-1  s-1 , respectively. To verify the application of the PDPADPP OFETs in high-voltage logic circuits, compact modeling using the industry-standard small-signal Berkeley short-channel IGFET model (BSIM) is performed, and the logic application characteristics are evaluated. The circuit simulation results demonstrate excellent logic application performance of the PDPADPP-based ambipolar transistor and illustrate that the device annealed at 240 °C exhibits ideal circuit characteristics.


Assuntos
Acrilonitrila , Simulação por Computador , Eletricidade , Elétrons , Nitrilas , Polímeros
9.
J Thorac Cardiovasc Surg ; 167(3): 1166-1176.e2, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37558202

RESUMO

OBJECTIVE: Volatile organic compounds (VOCs) are used in the sterilization and manufacture of medical equipment. These compounds have high vapor pressures with low water solubility and are emitted as gases from solids or liquids. They can be mutagenic, neurotoxic, genotoxic, and/or carcinogenic. Safe limits of exposure are not known for neonates. This study examined determinants of exposure in newborns undergoing cardiac surgery. METHODS: Twenty metabolites of 16 VOCs (eg, xylene, cyanide, acrolein, acrylonitrile, N, N-dimethylformamide, 1,3-butadiene, styrene, and benzene) were measured as metabolites in daily urine samples collected from 10 neonates undergoing cardiac operations (n = 150 samples). Metabolites were quantified using reversed-phase ultra-high performance liquid chromatography and electrospray ionization tandem mass spectrometry. Repeated measures analysis of covariance was performed for each metabolite to examine associations with use of medical devices. RESULTS: At least 3 metabolites were detected in every sample. The median number of metabolites detected in each sample was 14 (range, 3-15). In a model controlling for other factors, the use of extracorporeal membrane oxygenation was associated with significantly (P ≤ .05) greater metabolite levels of acrolein, acrylonitrile, ethylene oxide, propylene oxide, styrene, and ethylbenzene. Patients breathing ambient air had greater levels of metabolites of acrolein, xylene, N,N-dimethylformamide, methyl isocyanate, cyanide, 1,3-butadiene (all P ≤ .05). CONCLUSIONS: Exposure to volatile organic compounds is pervasive in newborns undergoing cardiac surgery. Sources of exposure likely include medical devices and inhalation from the air in the intensive care unit. The contribution of VOC exposure during cardiac surgery in newborns to adverse outcomes warrants further evaluation.


Assuntos
Acrilonitrila , Poluentes Atmosféricos , Butadienos , Procedimentos Cirúrgicos Cardíacos , Compostos Orgânicos Voláteis , Humanos , Recém-Nascido , Compostos Orgânicos Voláteis/análise , Poluentes Atmosféricos/urina , Acroleína/análise , Xilenos/análise , Acrilonitrila/análise , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Cianetos/análise , Estirenos/análise
10.
Macromol Rapid Commun ; 45(7): e2300666, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38134449

RESUMO

Copolymerization provides an effective approach to tune the photophysical properties of non-conventional luminescent polymers (NCLPs). In this study, the controlling of intrinsic emissions of polyacrylonitrile (PAN) copolymers is revealed by a delicate difference of secondary monomers. The introduction of methacrylate comonomers can induce a 70-nm red-shifting in the PL emission of copolymers compared with that of acrylate-containing copolymers. The mechanism of such "copolymerization induced red-shifting" in PAN copolymers is investigated. It is demonstrated that the presence of the α-methyl group in the copolymers can enhance the chain rigidity and through-space conjugation (TSC) of C≡N groups, resulting in the red-shifting of emission.


Assuntos
Acrilonitrila , Luminescência , Polímeros , Metacrilatos , Polimerização
11.
Sci Rep ; 13(1): 22486, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-38110432

RESUMO

A novel series of α-cyano indolylchalcones was prepared, and their chemical structures were confirmed based on the different spectral data. Among them, compound 7f was observed to be the most effective bioactive chalcone with distinguished potency and selectivity against colorectal carcinoma (HCT116) with IC50 value (6.76 µg/mL) relative to the positive control (5 FU) (77.15 µg/mL). In a preliminary action study, the acrylonitrile chalcone 7f was found to enhance apoptotic action via different mechanisms like inhibition of some anti-apoptotic protein expression, regulation of some apoptotic proteins, production of caspases, and cell cycle arrest. All mechanisms suggested that compound 7f could act as a professional chemotherapeutic agent. Also, a molecular docking study was achieved on some selected proteins implicated in cancer (Caspase 9, XIAP, P53 mutant Y220C, and MDM2) which showed variable interactions with compound 7f with good Gibbs free energy scores.


Assuntos
Acrilonitrila , Antineoplásicos , Carcinoma , Chalconas , Neoplasias do Colo , Humanos , Proteína Supressora de Tumor p53/metabolismo , Acrilonitrila/farmacologia , Simulação de Acoplamento Molecular , Chalconas/farmacologia , Chalconas/química , Células HCT116 , Apoptose , Neoplasias do Colo/tratamento farmacológico , Indóis/farmacologia , Antineoplásicos/química , Proliferação de Células
12.
J Food Sci ; 88(12): 4928-4941, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37905708

RESUMO

This study validated an analytical technique using headspace gas chromatography with flame ionization detection to quantify acrylonitrile monomer with a quantification limit of 0.10 ± 0.04 µg kg-1 . Subsequently, the acrylonitrile migration from polypropylene granules was evaluated in food simulants water and ethanol (50% v/v) and at two temperatures (20 ± 1°C and 44 ± 2°C) for up to 6 weeks, representing the service time of a bottle. From the experimental data obtained, pseudo-second-order kinetics were adjusted to represent the acrylonitrile migration into the simulants. For water, equilibrium concentrations of 13.58 and 16.58 µg kg-1 at 20 and 44°C, respectively, were obtained, while for 50% ethanol, 15.07 and 16.40 µg kg-1 were obtained for the same temperatures. The experimental results and the values estimated from the migration kinetics indicate that the maximum acrylonitrile concentration will not exceed the tolerable specific limit established in regulations. PRACTICAL APPLICATION: The migration of compounds such as acrylonitrile can be a drawback resulting in an undesirable reduction in the shelf life of liquid foods packaged in bottles made of materials such as polypropylene. In this paper, acrylonitrile migration kinetics and a methodology are proposed to determine whether the tolerable migration limits are ever reached, which can serve as a tool for producers of this type of packaging of food to predict shelf life.


Assuntos
Acrilonitrila , Embalagem de Alimentos , Polipropilenos , Acrilonitrila/análise , Etanol/química , Água/química , Contaminação de Alimentos/análise
13.
J Chromatogr A ; 1711: 464442, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37844445

RESUMO

Owing to the growing emphasis on child safety, it is greatly urgent to identify and assess the unknown compounds and discriminate the recycled materials for plastic toys. In this study, gas chromatography mass spectrometry coupled with static headspace has been optimized by response surface methodology for non-targeted screening of unknown volatiles in acrylonitrile-butadiene-styrene (ABS) plastic toys. Optimum conditions for static headspace were 120 °C for extraction temperature and 48 min for extraction time. A total of 83 volatiles in 11 categories were qualitatively identified by matching the NIST database library, retention index and standard materials. Considering high positive rate and potential toxicity, high-risk volatiles in ABS plastic toys were listed and traced for safety pre-warning. Moreover, the differential volatiles between virgin and recycled ABS plastics were screened out by orthogonal partial least-squares discrimination analysis. Principal component analysis, hierarchical cluster analysis and linear discrimination analysis were employed to successfully discriminate recycled ABS plastic toys based on the differential volatiles. The proposed strategy represents an effective and promising analytical method for non-targeted screening and risk assessment of unknown volatiles and discrimination of recycled materials combining with various chemometric techniques for children's plastic products to safeguard children's health.


Assuntos
Acrilonitrila , Estireno , Criança , Humanos , Butadienos/análise , Quimiometria , Plásticos/química
14.
J Environ Manage ; 348: 119080, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37827086

RESUMO

Environmental concerns associated with the rapid rising plastic consumption have led to the search for better waste utilization and management. Pyrolysis has emerged as an ideal and promising technique for energy extraction from plastic waste. The aim of this work is to explore the waste plastic pyrolysis behavior under non-isothermal heating conditions. The decomposition characteristics, reaction mechanism, kinetics and thermodynamics of a typical widely used thermosetting plastic, acrylonitrile butadiene styrene (ABS), were studied via coupled thermogravimetry, Fourier transform infrared spectrometry and gas chromatography-mass spectrometry analysis (TG-FTIR-GC/MS). Kinetic analysis showed the average Eα values are estimated to be 187.02, 188.55, 187.04 and 185.67 kJ/mol via advanced Vyazovkin, Flynn-Wall-Ozawa (FWO), Tang and Starink model-free method, respectively. Model-fitting CR and master-plots method indicated that f(α)=(1-α)n is the most probable reaction mechanism. The equation of kinetic compensation effect was further developed as lnA = -3.1955 + 0.1736 Eα. Based on these initial inferences, a new reaction scheme coupled with Particle Swarm Optimization (PSO) was put forward for modeling ABS pyrolysis. The optimized values of E, A and n are 198.07 kJ/mol, 7.61 × 1012 s-1 and 1.56, respectively. The predicted results showed that the experimental data can be well characterized by the optimized parameters from PSO, validating the effectiveness and accuracy of the inverse modeling procedure. Moreover, it is found that the volatile products are mainly composed of aromatic compounds, ketones, amines, esters, nitrile compounds, alkenes and amines. Based on the FT-IR and GC-MS results, the possible chemical reactions for ABS pyrolysis from molecular structure were proposed. Finally, thermodynamic analysis was carried out, the calculated values of enthalpy ΔH, Gibb's free energy ΔG and entropy ΔS indicated that non-spontaneous reactions with low favorability exists during ABS decomposition, the process is complex therefore extra energy is needed to promote the reaction. The obtained results should offer as an important reference for future disposal and thermochemical management of such polymer waste.


Assuntos
Acrilonitrila , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Butadienos , Estireno , Termogravimetria , Aminas
15.
Environ Sci Technol ; 57(37): 13980-13990, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37668438

RESUMO

The rise of electronics inevitably induced the co-pollution of novel brominated flame retardants (NBFRs) and microplastics (MPs). However, studies on how they interact to influence their bioavailability are scarce. Here, we explored the influence mechanism of acrylonitrile butadiene styrene (ABS)-MPs on the bioaccumulation of decabromodiphenyl ethane (DBDPE) in soil-earthworm microcosms. The influence exhibited a temporal pattern characterized by short-term inhibition and long-term promotion. After 28 days of exposure, DBDPE bioaccumulation in a co-exposure (10 mg kg-1 DBDPE accompanied by 1000 mg kg-1 ABS-MPs) was 2.61 times higher than that in a separate exposure. The adsorption process in the soil, intestines, and mucus introduced DBDPE-carried MPs, which had a higher concentration of DBDPE than the surrounding soil and directly affected the bioavailability of DBDPE. MP-pre-exposure (100, 1000, and 10000 mg kg-1) reduced epidermal soundness, mucus secretion, and worm cast production. This eventually promoted the contact between earthworm and soil particles and enhanced the DBDPE of earthworm tissue by 6%-61% in the next DBDPE-postexposure period, confirming that MPs increased DBDPE bioaccumulation indirectly by impairing the earthworm health. This study indicates that MPs promoted DBDPE bioaccumulation via adsorption and self-toxicity, providing new insight into the combined risk of MPs and NBFRs.


Assuntos
Acrilonitrila , Retardadores de Chama , Oligoquetos , Animais , Bioacumulação , Microplásticos , Plásticos , Solo
16.
J Agric Food Chem ; 71(47): 18239-18249, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37722018

RESUMO

The identification of novel pyrazolyl acrylonitrile acaricides with improved properties is of great value for the control of phytophagous mites. A series of innovative silicon-containing pyrazolyl acrylonitriles were rationally designed by applying a bioisosteric carbon-silicon replacement strategy and prepared based on novel synthetic methodology. As a result of our research, we discovered compound A25 which possesses outstanding acaricidal activity. With an LC50 value of 0.062 mg/L, compound A25 was found to be 2.3-fold and 1.9-fold more potent than the commercial acaricides cyenopyrafen and cyetpyrafen, respectively. Enzymatic inhibitory assay indicated that the active principle M1 of compound A25 possesses an IC50 value of 2.32 µM against Tetranychus cinnabarinus SDH, which was about twofold superior compared to the active metabolites of cyenopyrafen (IC50 = 4.72 µM). Molecular docking study showed that the active metabolites 2 and 3 and their corresponding silicon counterparts form H-bonds and cation-π interaction with the residues of Trp165, Tyr433, and Arg279.


Assuntos
Acaricidas , Acrilonitrila , Tetranychidae , Animais , Acaricidas/química , Silício , Simulação de Acoplamento Molecular
17.
Environ Res ; 238(Pt 1): 117126, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37716383

RESUMO

Given the rise in both usage and disposal of dangerous electronics, there is a catastrophic rise in assemblage of electronic waste (e-waste). E-waste including various plastic resins are among the most frequently discarded materials in electronic gadgets. In current digital era, managing e-waste has become universal concern. From the viewpoint of persisting lacuna of e-waste managing methods, the current study is designed to fabricate an eco-friendly e-waste treatment with native soil bacteria employing an enrichment culture method. In the presence of e-waste, indigenous soil microbes were stimulated to degrade e-waste. Microbial cultures were isolated using enrichment medium containing acrylonitrile-butadiene styrene (ABS) as the primary carbon source. Priestia aryabhattai MGP1 was found to be the most dominant e-polymer degrading bacterial isolate, as it was reported to degrade ABS plastic in disposed-off television casings. Furthermore, to increase degradation potential of MGP1, Response Surface Methodology (RSM) was adopted which resulted in optimized conditions (pH 7, shaking-speed 120 rpm, and temperature 30 °C), for maximum degradation (18.88%) after 2 months. The structural changes induced by microbial treatment were demonstrated by comparing the findings of Field emission scanning electron microscopy (FESEM) images and Fourier Transform Infrared (FTIR) spectra confirming the disappearance of ≡ C─H peaks along with C-H, C=C and C ≡N bond destabilization following degradation. Energy-dispersive X-ray (EDX) analyzers of the native and decomposed e-polymer samples revealed a considerable loss in elemental weight % of oxygen by 8.4% and silica by 0.5%. Magnesium, aluminium and chlorine which were previously present in the untreated sample, were also removed after treatment by the bacterial action. When seeds of Vigna radiata were screened using treated soil in the presence of both e-waste and the chosen potent bacterial strain, it was also discovered that there was reduced toxicity in terms of improved germination and growth metrics as a phytotoxicity criterion.


Assuntos
Acrilonitrila , Resíduo Eletrônico , Estireno , Plásticos , Acrilonitrila/química , Butadienos/química , Biodegradação Ambiental , Solo , Resíduo Eletrônico/análise , Polímeros , Bactérias
18.
Int J Biol Macromol ; 253(Pt 4): 127068, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37758105

RESUMO

The aim of this study was to develop a lightweight epoxy based biocomposite for morphing wing and unmanned aerial vehicle (UAV) applications. The proposed composite was developed using a 3D printed high stiffness lignin-Acrylonitrile Butadiene Styrene (ABS) core and industrial hemp with aluminized glass fiber epoxy skin. The ABS was reinforced using lignin macromolecule derived from cashew nut shells via twin screw extruder and the core was printed using an industrial grade 3D printer. Furthermore, the composites were prepared by compression moulding with an ABS-lignin core and hemp/aluminized GF surface and characterized according to respective American society of testing and materials (ASTM) standards. The findings indicate that the addition of 30 vol% Al-glass and hemp fiber with lignin strengthened ABS core improved the mechanical properties. The composite material designated as "E2" exhibits the maximum mechanical properties, providing tensile strength, flexural strength, Izod impact, interlaminar shear strength (ILSS), and compression values of, 136 MPa, 168 MPa, 4.82 kJ/m2, 21 MPa, and 155 MPa respectively. The maximal energy absorbed by composite designation "E2," during drop load impact test is 20.6 J. Similarly, the composite designation "E2"gives fatigue life cycles of 33,709, 25,781 and 19,633 for 50 %, 70 % and 90 % of ultimate tensile strength (UTS) and 32.5 (K1c) MPa⋅m and 0.76 (G1c) MJ/m2 in fracture toughness and energy release rate respectively.


Assuntos
Acrilonitrila , Anacardium , Cannabis , Animais , Butadienos , Lignina , Nozes , Dispositivos Aéreos não Tripulados , Resinas Epóxi , Impressão Tridimensional , Estirenos
19.
Chemosphere ; 340: 139986, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37640213

RESUMO

In this study, we investigated the deactivation kinetics and mechanism of N-F-TiO2/SiO2 nanopowder as a model photocatalyst for the purpose of facilitating the photocatalytic degradation of acrylonitrile (AN) in aqueous environment. Prior research has already displayed the proficient degradation of AN through the utilization of N-F-TiO2/SiO2 catalysts, revealing a degradation efficiency of 81.2% within a span of 6 min at an initial AN concentration of 10 mg/L. Multiple variables including the initial AN concentration, illumination intensity, and initial pH value were extensively analyzed during the degradation process. The kinetics of photocatalytic degradation of AN, facilitated by the N-F-TiO2/SiO2 photocatalyst, were modeled by fitting the pseudo first-order reaction kinetics to each individual factor. Furthermore, the adverse effect of catalyst poisoning during the photocatalytic breakdown of AN using the N-F-TiO2/SiO2 photocatalyst was analyzed through a range of different techniques including SEM, XPS, BET, XRD, TG, and NH3-TPD. The incorporation of findings from these diverse techniques revealed that, the primary factors contributing to the photocatalyst's poisoning were as follows: (i) During the degradation process, the build-up of intermediate molecules on active sites hindered their functionality, leading to a decrease in the efficiency of the photocatalytic reaction, (ii) Carbonaceous deposits formed when the catalyst's pore structure was obstructed by pollutants or intermediate products that had not undergone timely photocatalytic breakdown and (iii) The persistent erosion of active sites due to hydraulic forces resulted in inadequate performance of the N-F-TiO2/SiO2 photocatalyst in aqueous solutions. A comprehensive analysis of the deactivation kinetics was conducted, deciding in the formulation of a detailed poisoning mechanism for the N-F-TiO2/SiO2 photocatalyst. Additionally, we explored the catalysts regeneration, involving thermal treatment, ultrasonic irradiation, and catalyst reloading. This study not only advances our insight into the waning performance of catalysts in aqueous media but also establishes a conceptual framework for extrapolating analogous deactivation dynamics in other catalysts, grounded in precedent experimental knowledge. This research contributes to the development of a deactivation model for catalysts in the aqueous environment, based on existing experimental research, providing a theoretical framework for understanding the deactivation process of photocatalysts.


Assuntos
Acrilonitrila , Nanopartículas , Flúor , Dióxido de Silício , Nitrogênio
20.
Environ Sci Pollut Res Int ; 30(43): 98300-98313, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37606772

RESUMO

Legacy brominated flame retardants (BFRs) in printed circuit boards are gradually being replaced by novel BFRs (NBFRs). Safe disposal and recycling of polymeric constituents in the polymeric fractions of e-waste necessitate the removal of their toxic and corrosive bromine content. This is currently acquired through thermal recycling operations involving the pyrolysis of BFRs-containing materials with metal oxides. Nonetheless, the debromination capacity toward NBFRs is yet to be established. Thus, this study aims to address these two crucial gaps in the current knowledge pertaining to the plausible formation of brominated toxicants from the thermal decomposition of NBFRs and their thermal recycling potential. Herein, we investigate the pyrolysis of a mixture of 2,4,6-tribromophenol (TBP), allyl 2,4,6-tribromophenyl ether (ATE) and Tetrabromobisphenol A-bis (2,3-dibromo propyl ether) (TBBPA-DBPE) in the presence of acrylonitrile butadiene styrene (ABS) polymers at various loads. To demonstrate a viable debromination route, pyrolysis of NBFRs-ABS mixture with Ca(OH)2 was also investigated. The latter is a potent debromination agent for legacy BFRs. Upon pyrolysis with Ca(OH)2, the bromine content in the collected oil was reduced up to 80.49% between 25-500 °C. Products of the co-pyrolysis process generally feature non-brominated aromatic and aliphatic compounds; a finding that indicates an effective thermal recycling approach. As evident by IC measurements, no HBr emission could be detected when Ca(OH)2 is added to the mixture. As XRD patterns show, Ca(OH)2 is partially converted into CaBr2. DFT calculations provide pathways for the observed surface debromination characterized by surface-assisted fission of aromatic C-Br bonds and the formation of CaBr sites. Outcomes reported herein are instrumental to designing and operating a thermal recycling facility of polymeric materials contaminated with high loads of bromine, i.e., most notably during scenarios encountered in the thermal recycling of e-waste.


Assuntos
Acrilonitrila , Resíduo Eletrônico , Retardadores de Chama , Bromo , Polímeros , Poliestirenos
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