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1.
Ecotoxicol Environ Saf ; 203: 111021, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888607

RESUMO

Volatile iodine released from nuclear power plant reactors is radiological hazard to environment and human's health because of their high fission yield and environmental mobility. The complexity of nuclear waste management motivated the development of solid-phase adsorbents. Herein, co-radiation induced graft polymerization (CRIGP) was employed in the graft polymerization of N-vinyl-2-pyrrolidone (NVP) onto polyethylene-coated polypropylene skin-core (PE/PP) fibers using electron beam (EB) irradiation. This work provides a one-step green synthetic approach to prepare iodine fibrous adsorbents without any chemical initiators or large amount of organic solvent. The original and modified PE/PP fibers were characterized by fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric (TG) and scanning electron microscopy (SEM) to demonstrate the grafting of NVP onto the PE/PP fibers. The capacity of iodine absorbed by the PE/PP-g-PNVP fibers was 1237.8 mg/g after 180 min. Meanwhile, absorbents can be regenerated efficiently by two different means of ethanol elution and heating at 120 °C, respectively. Within 10 min, 94.17% and 90.12% of the iodine can be released from the PE/PP-g-PNVP fibers with these two methods, respectively. The adsorbent exhibited a long service life of at least ten adsorption-desorption cycles, suggesting that PE/PP-g-PNVP fibers might be a promising adsorbent for volatile iodine adsorption from fission products in nuclear power plant reactors.


Assuntos
Poluentes Radioativos do Ar/análise , Raios gama , Química Verde/métodos , Iodo/análise , Polipropilenos/química , Pirrolidinonas/química , Adsorção , Humanos , Cinética , Polimerização , Polipropilenos/efeitos da radiação , Pirrolidinonas/efeitos da radiação , Propriedades de Superfície
2.
Ecotoxicol Environ Saf ; 204: 111112, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32798756

RESUMO

Compared with conventional methods for organic pollutant degradation, photocatalysis is a promising treatment technology with broad application prospects. Bi2O2CO3 is often used for organic pollutants degradation but greatly restricted by having drawbacks of large band gap and high electron-hole recombination rate. Herein, heterostructured Bi2O2CO3 (BOC)/reduced graphene oxide (rGO)/polydopamine (PDA) (BGP) photocatalysts were first designed through a green chemical method. By incorporating rGO and PDA in BOC, the kinetic constant of BGP to catalytically degrade methyl orange (MO) was significantly increased; over fourfold elevated rather than that of BOC (kapp/BOC = 0.0019, kapp/BGP = 0.0089) due to the high electron transfer capability of rGO and superior adhesive force and semiconducting properties of PDA. DRS and photoelectrochemical results confirmed the improvement of the light absorption range and charge transfer capability because of the synergistic effect of rGO and PDA. Results of trapping experiment and ESR unraveled the catalytic mechanism that both holes (h+) and superoxide radicals (•O2-) were the main oxidative species for MO degradation. Economic assessment results demonstrated that Bi2O2CO3/rGO/PDA heterojunctions have great potentials in the field of organic wastewater purification. This study developed a low-cost and highly efficient BGP material and provided a deep understanding of the structure-performance relationships of materials for organic pollutant degradation.


Assuntos
Processos Fotoquímicos , Eliminação de Resíduos Líquidos/métodos , Compostos Azo , Catálise , Poluentes Ambientais , Grafite , Química Verde , Indóis , Oxirredução , Polímeros , Águas Residuárias
3.
Int J Nanomedicine ; 15: 5345-5360, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801693

RESUMO

Background: Soft corals have been endorsed as a plentiful source of bioactive compounds with promising anti-inflammatory activities; therefore, exploring their potential as source of anti-inflammatory metabolites has stimulated a growing research interest. Purpose: To investigate the anti-inflammatory potential of the soft coral, Nephthea sp., in its bulk and silver nanostructure. Metabolomics analysis of Nephthea sp., followed by molecular docking studies, was also conducted in order to explore and predict the secondary metabolites that might provide its inhibitory actions on inflammation. Materials and Methods: The petroleum ether and ethyl acetate fractions were used to synthesize silver nanoparticles. The prepared silver nanoparticles were characterized through UV-vis spectrophotometric, transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR) analyses. Testing for the anti-inflammatory activity was performed against COX-1 and COX-2. Furthermore, liquid chromatography-mass spectrometry (LC-MS) based metabolomics analysis and molecular docking were also applied. Results: A variety of secondary metabolites were identified, among them, sesquiterpenes were found to prevail. The petroleum ether and acetone fractions of Nephthea sp. showed the highest COX-2 inhibitory activities, possibly attributable to their substantial contents of terpenoids. Additionally, the green synthesized silver nanoparticles of both the petroleum ether and ethyl acetate fractions of Nephthea sp. demonstrated higher anti-COX-2 properties. Conclusion: The obtained results showed the effectiveness of non-targeted metabolomics technique in metabolic profiling of Nephthea sp., helping the search for new bioactive metabolites in future chemical studies on this soft coral. The interesting anti-inflammatory potential of the tested extracts and their nanoparticles could also be relevant to the development of new, effective anti-inflammatory agents.


Assuntos
Antozoários/metabolismo , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Nanopartículas Metálicas/química , Prata/química , Alcanos/química , Animais , Antozoários/química , Anti-Inflamatórios/síntese química , Ciclo-Oxigenase 1/química , Ciclo-Oxigenase 1/metabolismo , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase/química , Inibidores de Ciclo-Oxigenase/farmacologia , Química Verde , Humanos , Metabolômica , Simulação de Acoplamento Molecular , Metabolismo Secundário , Sesquiterpenos/análise , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier
4.
PLoS One ; 15(8): e0237567, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797097

RESUMO

Distinct morphological MgO nanoparticles (MgONPs) were synthesized using biomasses of Saussurea costus roots. The biomass of two varieties of Saussurea costus (Qustal hindi and Qustal bahri) were used in the green synthesis of MgONPs. The physical and chemical features of nanoparticles were confirmed by spectroscopic and microscopic techniques. The surface morphology of the obtained nanoparticles was detected at different magnifications by SEM and TEM microscopy and the size of nanoparticles were found to be 30 and 34 nm for Qustal hindi and Qustal bahri, respectively. The antimicrobial activity of the prepared MgONPs was screened against six pathogenic strains. The synthesized nanoparticles by Qustal bahri biomass exerted significant inhibition zones 15, 16, 18, 17, 14, and 10 mm against E. coli, P. aeruginosa, C. tropicalis and C. glabrata, S. aureus and B. subtilis as compared to those from Qustal hindi 12, 8 and 17 mm against B. subtilis, E. coli and C. tropicalis, respectively. MgONPs showed a potential cytotoxicity effect against MCF-7 breast cancer cell lines. Cellular investigations of MgONPs revealed that the prepared nanoparticles by Qustal bahri exhibited high cytotoxicity against MCF-7 cancer cell lines. IC50 values in MCF-7 cells were found to be 67.3% and 52.1% for MgONPs of Saussurea costus biomasses, respectively. Also, the photocatalytic activity of MgONPs of each Saussurea costus variety was comparatively studied. They exhibited an enhanced photocatalytic degradation of methylene blue after UV irradiation for 1 h as 92% and 59% for those prepared by Qustal bahri and Qustal hindi, respectively. Outcome of results revealed that the biosynthesized MgONPs showed promising biomedical potentials.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Óxido de Magnésio/farmacologia , Azul de Metileno/química , Saussurea/química , Anti-Infecciosos/química , Antineoplásicos/química , Bactérias/efeitos dos fármacos , Biomassa , Catálise , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Fungos/efeitos dos fármacos , Química Verde , Humanos , Células MCF-7 , Óxido de Magnésio/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Processos Fotoquímicos , Extratos Vegetais/química , Raízes de Plantas/química
5.
Molecules ; 25(15)2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32731428

RESUMO

In 2020, the world is being ravaged by the coronavirus, SARS-CoV-2, which causes a severe respiratory disease, Covid-19. Hundreds of thousands of people have succumbed to the disease. Efforts at curing the disease are aimed at finding a vaccine and/or developing antiviral drugs. Despite these efforts, the WHO warned that the virus might never be eradicated. Countries around the world have instated non-pharmaceutical interventions such as social distancing and wearing of masks in public to curb the spreading of the disease. Antiviral polysaccharides provide the ideal opportunity to combat the pathogen via pharmacotherapeutic applications. However, a layer-by-layer nanocoating approach is also envisioned to coat surfaces to which humans are exposed that could harbor pathogenic coronaviruses. By coating masks, clothing, and work surfaces in wet markets among others, these antiviral polysaccharides can ensure passive prevention of the spreading of the virus. It poses a so-called "eradicate-in-place" measure against the virus. Antiviral polysaccharides also provide a green chemistry pathway to virus eradication since these molecules are primarily of biological origin and can be modified by minimal synthetic approaches. They are biocompatible as well as biodegradable. This surface passivation approach could provide a powerful measure against the spreading of coronaviruses.


Assuntos
Antivirais/uso terapêutico , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Polissacarídeos/uso terapêutico , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/metabolismo , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/uso terapêutico , Química Verde , Humanos , Nanopartículas , Nanotecnologia , Polissacarídeos/farmacologia
7.
Food Chem ; 332: 127395, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615385

RESUMO

This paper describes a simple, efficient and rapid analytical method for extraction and determination of nitrite in meat and chicken products by vortex-assisted supramolecular solvent-based liquid phase microextraction (VA-SUPRAS-LPME) prior to spectrophotometric detection. The SUPRAS was rapidly formed by the addition of a colloidal decanoic acid suspension to tetrahydrofuran (THF). The validation studies were carried out in terms of linearity, limit of detection (LOD), limit of quantitation (LOQ), matrix effects, robustness, uncertainty measurement, precision, accuracy, and certified reference material (CRM) analysis using optimized experimental conditions. The LOD, LOQ, linearity and matrix effect were 0.035 ng mL-1, 0.1 ng mL-1, 0.1-300 ng mL-1, and 9.6% respectively, with high preconcentration factor (200). The method was successfully applied for the determination of nitrite in processed products. Moreover, the results obtained by the proposed method were compared to the standard Griess method, and showed no significant differences in term of Student's t-test.


Assuntos
Galinhas , Análise de Alimentos/métodos , Microextração em Fase Líquida/métodos , Carne/análise , Nitritos/análise , Nitritos/isolamento & purificação , Solventes/química , Animais , Contaminação de Alimentos/análise , Manipulação de Alimentos , Química Verde , Humanos , Limite de Detecção , Espectrofotometria Ultravioleta
8.
PLoS One ; 15(7): e0234964, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614844

RESUMO

In this study, a facile, ecological and economical green method is described for the fabrication of iron (Fe), copper (Cu) and silver (Ag) nanoparticles (NPs) from the extract of Syzygium cumini leaves. The obtained metal NPs were categorized using UV/Vis, SEM, TEM, FTIR and EDX-ray spectroscopy techniques. The Fe-, Cu- and Ag-NPs were crystalline, spherical and size ranged from 40-52, 28-35 and 11-19 nm, respectively. The Ag-NPs showed excellent antimicrobial activities against methicillin- and vancomycin-resistance Staphylococcus aureus bacterial strains and Aspergillus flavus and A. parasiticus fungal species. Furthermore, the aflatoxins (AFs) production was also significantly inhibited when compared with the Fe- and Cu-NPs. In contrast, the adsorption results of NPs with aflatoxin B1 (AFB1) were observed as following order Fe->Cu->Ag-NPs. The Langmuir isotherm model well described the equilibrium data by the sorption capacity of Fe-NPs (105.3 ng mg-1), Cu-NPs (88.5 ng mg-1) and Ag-NPs (81.7 ng mg-1). The adsorption was found feasible, endothermic and follow the pseudo-second order kinetic model as revealed by the thermodynamic and kinetic studies. The present findings suggests that the green synthesis of metal NPs is a simple, sustainable, non-toxic, economical and energy-effective as compared to the others conventional approaches. In addition, synthesized metal NPs might be a promising AFs adsorbent for the detoxification of AFB1 in human and animal food/feed.


Assuntos
Aflatoxina B1/isolamento & purificação , Anti-Infecciosos/metabolismo , Biotecnologia/métodos , Cobre , Química Verde/métodos , Ferro , Nanopartículas Metálicas , Extratos Vegetais/metabolismo , Folhas de Planta/metabolismo , Prata , Desintoxicação por Sorção , Syzygium/metabolismo , Adsorção , Anti-Infecciosos/farmacologia , Aspergillus/efeitos dos fármacos , Aspergillus flavus/efeitos dos fármacos , Técnicas de Química Analítica , Cobre/administração & dosagem , Cobre/farmacologia , Resistência Microbiana a Medicamentos , Ferro/administração & dosagem , Ferro/farmacologia , Cinética , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Oxirredução , Prata/administração & dosagem , Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Termodinâmica , Vancomicina/farmacologia
9.
Int J Nanomedicine ; 15: 3791-3801, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547028

RESUMO

Purpose: Paclitaxel is a generic drug produced based on Taxol which is an extract of Taxus tree, well known for its anticancer and antibacterial effects. This study was aimed at building up an agent with the antibacterial and anticancer benefits of both the silver ions and Taxol, together with less cytotoxic effects. Materials and Methods: Colloidal silver nanoparticles (AgNPs) were synthesized by reducing aqueous AgNO3 with aqueous Taxus leaf extract at nonphotomediated conditions, without any catalyst, template or surfactant. The AgNP production was confirmed by ultraviolet-visible (UV-VIS) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier-transform infrared (FTI) spectroscopy. The MTT assay for human breast cancer cells as well as the DAPI fluorescent staining microscopy tested the biocompatibility and anticancer effects of AgNPs, silver nitrate, and Taxol. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) techniques were performed to determine the shape and size of the nanoparticles. MTT assay showed the best inhibitory concentration of AgNPs on cancer cells. The antibacterial activity of the three case study materials was tested for gram-positive (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) using well diffusion test. Results: This work proposes more anticancer effects for AgNP made by Taxus brevifolia extract, comparing Taxol solution. IC50 was observed as 3.1 mM for Taxol while 1.5 mM for new AgNP. Moreover, Taxus showed no antibacterial effects while the new AgNP showed a dose-dependent biocompatibility along with slightly more antibacterial effects (MIC: 1.6 and 6.6mM for gram-positive and -negative bacteria, respectively) comparing with silver nitrate solution (MIC: 1.5 and 6.2 mM for gram-positive and -negative bacteria, respectively). Conclusion: The production of herbal-mediated silver nanoparticles may be an efficient substitution for the silver nitrate-based medicines with less side effects.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Química Verde/métodos , Nanopartículas Metálicas/uso terapêutico , Prata/farmacologia , Taxus/química , Difusão Dinâmica da Luz , Escherichia coli/efeitos dos fármacos , Humanos , Células MCF-7 , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/química , Staphylococcus aureus/efeitos dos fármacos
10.
Int J Nanomedicine ; 15: 3377-3389, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32494136

RESUMO

Background: Hepatitis C virus (HCV) infection is a major cause of hepatic diseases all over the world. This necessitates the need to discover novel anti-HCV drugs to overcome emerging drug resistance and liver complications. Purpose: Total extract and petroleum ether fraction of the marine sponge (Amphimedon spp.) were used for silver nanoparticle (SNP) synthesis to explore their HCV NS3 helicase- and protease-inhibitory potential. Methods: Characterization of the prepared SNPs was carried out with ultraviolet-visible spectroscopy, transmission electron microscopy, and Fourier-transform infrared spectroscopy. The metabolomic profile of different Amphimedon fractions was assessed using liquid chromatography coupled with high-resolution mass spectrometry. Fourteen known compounds were isolated and their HCV helicase and protease activities assessed using in silico modeling of their interaction with both HCV protease and helicase enzymes to reveal their anti-HCV mechanism of action. In vitro anti-HCV activity against HCV NS3 helicase and protease was then conducted to validate the computation results and compared to that of the SNPs. Results: Transmission electron-microscopy analysis of NPs prepared from Amphimedon total extract and petroleum ether revealed particle sizes of 8.22-14.30 nm and 8.22-9.97 nm, and absorption bands at λmax of 450 and 415 nm, respectively. Metabolomic profiling revealed the richness of Amphimedon spp. with different phytochemical classes. Bioassay-guided isolation resulted in the isolation of 14 known compounds with anti-HCV activity, initially revealed by docking studies. In vitro anti-HCV NS3 helicase and protease assays of both isolated compounds and NPs further confirmed the computational results. Conclusion: Our findings indicate that Amphimedon, total extract, petroleum ether fraction, and derived NPs are promising biosources for providing anti-HCV drug candidates, with nakinadine B and 3,4-dihydro-6-hydroxymanzamine A the most potent anti-HCV agents, possessing good oral bioavailability and penetration power.


Assuntos
Simulação por Computador , DNA Helicases/antagonistas & inibidores , Química Verde , Metabolômica , Nanopartículas Metálicas/química , Poríferos/química , Prata/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Alcanos/química , Animais , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Oceano Índico , Nanopartículas Metálicas/ultraestrutura , Simulação de Acoplamento Molecular , Peptídeo Hidrolases/metabolismo , Inibidores de Proteases/farmacologia , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Int J Nanomedicine ; 15: 2541-2553, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368039

RESUMO

Background: In the emerging field of nanotechnology, copper oxide (CuO) nanomaterials are considered to be one of the most important transition metal oxides owing to its fascinating properties. Its synthesis from green chemistry principles is gaining importance as next-generation antibiotics due to its simplicity, eco-friendliness, and cost-effectiveness. In the present study, CuO nanorods (CuO NRs) were synthesized from the aqueous fruit extract of Momordica charantia and characterized using different analytical techniques. Further, the biomedical therapeutic potential was evaluated against multi-drug resistant microbial strains. Materials and Methods: To synthesize CuO NRs, 0.1M of CuSO4.5H2O solution was added to aqueous extract of Momordica charantia in a 1:3 (v/v) ratio (pH=11) and heated at 50°C followed by washing and drying. The synthesized CuO NRs were subjected to characterization using different analytical techniques such as UV visible spectroscopy, zeta sizer equipped with zeta potential, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). Further, the application as a biomedical therapeutic potential was evaluated in vitro using well diffusion method against eleven multidrug-resistant clinical bacterial strains, a fungus- Trichophyton rubrum and in ovo against the R2B virus using haemagglutination (HA) test. Results: Characterization was preliminarily done by the spectral study that confirms the absorbance band at 245nm. FTIR analysis at 628 cm-1 peak identified copper oxide vibration. SEM analysis revealed agglomerated particle clusters. However, with TEM clear nanorods of average diameter of 61.48 ± 2 nm were observed. EDAX confirmed CuO formation while XRD showed a typical monoclinic structure with 6 nm crystallite size. Biological screening of CuO NRs showed significant results against both in vitro and in ovo methods. Significant inhibitory activity (p<0.0001) was noted against most of the resistant human pathogenic strains including both Gram-positive and Gram-negative bacteria. The highest efficacy was observed against Bacillus cereus with a 31.66 mm zone of inhibition. Besides, the therapeutic potential of CuO NRs against Corynebacterium xerosis, Streptococcus viridians and R2B strain of Newcastle disease is reported for the first time. Conclusion: Based on the present results, it could be expected that green synthesized CuO NRs would find potential applications in the field of nanomedicine.


Assuntos
Antibacterianos/farmacologia , Cobre/farmacologia , Química Verde , Momordica charantia/química , Nanoestruturas/química , Animais , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Galinhas , Fungos/efeitos dos fármacos , Testes de Hemaglutinação , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Nanoestruturas/ultraestrutura , Nanotubos/química , Nanotubos/ultraestrutura , Tamanho da Partícula , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Difração de Raios X
12.
Ecotoxicol Environ Saf ; 200: 110780, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32470683

RESUMO

A green synthesis method for nanoscale silver using ß-cyclodextrin as both reducing agent and stabilizer was developed. ß-cyclodextrin was used not only as a reducing agent but also a stabilizing agent for nano-silver, and is also an excellent detection substrate due to its special structure (inner hydrophobic and outer hydrophilic ring structure). Then, the green synthesized silver nanoparticles were used as Surface-enhanced Raman spectroscopy (SERS) enhanced substrates to detect polycyclic aromatic hydrocarbons, such as: anthracene, pyrene, chrysene and triphenylene. The SERS substrate can be used for both quantitative detection of the four polycyclic aromatic hydrocarbons and qualitative identification of mixtures of these hydrocarbons. This synthesis method is simple and convenient, having great potential in simultaneous and rapid detection of environmental organic pollutants.


Assuntos
Química Verde/métodos , Nanopartículas Metálicas/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Prata/química , Análise Espectral Raman/métodos , beta-Ciclodextrinas/química , Antracenos/análise , Crisenos/análise , Interações Hidrofóbicas e Hidrofílicas , Pirenos/análise
13.
Food Chem ; 328: 127097, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32470774

RESUMO

In this study, polyaniline modified polyacrylonitrile nanofibers mat (PANI NFsM) was prepared as a novel adsorbent for the solid-phase extraction (SPE) of non-steroidal anti-inflammatory drug residues in meat or egg samples. The solvent extracts of samples were simply diluted with water to perform the SPE, and then the eluent was directly analyzed. Significant reduction of the matrix effect was obtained after SPE using only 5 mg of PANI NFsM. The entire sample preparation time is 5-10 times lower than the existing methods. The limits of detection of the target analytes ranging from 0.6 to 12.2 µg kg-1 had already met the demand of food safety monitoring by only 1 g sample. The recoveries ranged from 85.18% to 107.31%, with the intra-day and inter-day relative standard deviations of 2.74% to 16.01%, revealing satisfactory accuracy and precision. Finally, real samples analyses were applied to verify the practicability of the method.


Assuntos
Compostos de Anilina/química , Ração Animal/análise , Resíduos de Drogas/análise , Resíduos de Drogas/isolamento & purificação , Nanofibras/química , Extração em Fase Sólida/métodos , Resinas Acrílicas/química , Animais , Anti-Inflamatórios não Esteroides/análise , Anti-Inflamatórios não Esteroides/isolamento & purificação , Química Verde , Limite de Detecção , Fatores de Tempo
14.
Food Chem ; 326: 126965, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32413755

RESUMO

Natural deep eutectic solvents (NADES) were introduced for the extraction of free seleno-amino acids from lyophilized and powdered milk samples. Different NADES were evaluated, and lactic acid:glucose (LGH) showed the highest selenium recoveries. Selenium analysis was performed by inductively coupled plasma mass spectrometry (ICP MS). Se-NADES analysis in ICP MS was optimized according to the radio frequency power and nebulization gas flow rate. Se-NADES extraction was optimized by an experimental design. LGH dilution, LGH volume, sample quantity, and ultrasound time were factors influencing the extraction. Seleno-amino acids were determined by liquid chromatography-ICP MS. After optimization, the limits of detection obtained were 7.37, 8.63, and 9.64 µg kg-1 for selenocysteine, selenomethionine, and seleno-methyl-selenocysteine, respectively. The NADES-extraction is a green procedure with 2 penalty points in the EcoScale. The method was applied to the analysis of powdered milk, lyophilized Se-fortified sheep milk, and ERM-BD151 skimmed milk powder.


Assuntos
Análise de Alimentos/métodos , Leite/química , Selenocisteína/análogos & derivados , Selenocisteína/análise , Selenometionina/análise , Animais , Fracionamento Químico/métodos , Cromatografia Líquida , Feminino , Alimentos Fortificados/análise , Liofilização , Química Verde , Limite de Detecção , Espectrometria de Massas/métodos , Pós/química , Selênio/análise , Ovinos , Solventes/química
16.
Nat Commun ; 11(1): 1956, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32327665

RESUMO

The dehydrogenative alkenylation of C-H bonds with alkenes represents an atom- and step-economical approach for olefin synthesis and molecular editing. Site-selective alkenylation of alkanes and aldehydes with the C-H substrate as the limiting reagent holds significant synthetic value. We herein report a photocatalytic method for the direct alkenylation of alkanes and aldehydes with aryl alkenes in the absence of any external oxidant. A diverse range of commodity feedstocks and pharmaceutical compounds are smoothly alkenylated in useful yields with the C-H partner as the limiting reagent. The late-stage alkenylation of complex molecules occurs with high levels of site selectivity for sterically accessible and electron-rich C-H bonds. This strategy relies on the synergistic combination of direct hydrogen atom transfer photocatalysis with cobaloxime-mediated hydrogen-evolution cross-coupling, which promises to inspire additional perspectives for selective C-H functionalizations in a green manner.


Assuntos
Aldeídos/química , Alcanos/química , Alcenos/química , Alcenos/síntese química , Catálise , Técnicas de Química Sintética , Química Verde , Estrutura Molecular , Compostos Organometálicos/química , Processos Fotoquímicos , Estereoisomerismo
17.
Food Chem ; 322: 126767, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32330787

RESUMO

Due to the lack of innovative valorization strategies, berry pomaces are a poorly utilized as a cheap source of valuable nutrients and phytochemicals. An effective biorefining scheme was developed to recover functional components from lingonberry pomace by consecutive supercritical CO2 (SFE-CO2), pressurized liquid (PLE) and enzyme assisted (EAE) extractions. SFE-CO2 at optimized parameters yielded 11.8 g/100 g of lipophilic fraction, containing 43.3 and 37.4% of α-linolenic and linoleic fatty acids, respectively. The combined PLE with ethanol and water additionally recovered 61.8 g/100 g of polar constituents and reduced the antioxidant capacity of starting material by up to 94%. The major portion of the antioxidants (89-94% in different assays), anthocyanins (231 mg/100 g pomace) and proanthocyanidins (15.9 g/100 g pomace) was present in PLE-EtOH extract. Cyanidin-3-galactoside was the major anthocyanin (146.9 mg/100 g). High-pressure fractionation was more efficient for obtaining bioactive pomace constituents as compared with conventional and enzyme-assisted extractions.


Assuntos
Fracionamento Químico/métodos , Solventes/química , Vaccinium vitis-Idaea , Gerenciamento de Resíduos/métodos , Antocianinas/análise , Antocianinas/química , Antioxidantes/análise , Antioxidantes/química , Dióxido de Carbono/química , Etanol/química , Frutas/química , Galactosídeos/análise , Galactosídeos/química , Química Verde , Resíduos Industriais , Complexos Multienzimáticos/química , Complexos Multienzimáticos/metabolismo , Pressão , Proantocianidinas/análise , Proantocianidinas/química , Água
18.
Chemosphere ; 253: 126737, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32302908

RESUMO

Bioaerosols have widely been a concern due to their potential harm to human health caused by the carrying and spreading of harmful microorganisms. Biofiltration has been generally used as a green and effective technology for processing VOCs. However, bioaerosols can be emitted into the atmosphere as secondary pollutants from the biofiltration process. This review presents an overview of bioaerosol emissions from gas bioreactors. The mechanism of bioaerosols production and the effect of biofiltration on bioaerosol emissions were analyzed. The results showed that the bioaerosol emission concentrations were generally exceeded 104 CFU m-3, which would damage to human health. Biomass, inlet gas velocity, moisture content, temperature, and some other factors have significant influences on bioaerosol emissions. Moreover, as a result of the analysis done herein, different inactivation technologies and microbial immobilization of bioaerosols were proposed and evaluated as a potential solution for reducing bioaerosols emissions. The purpose of this paper is to make more people realize the importance of controlling the emissions of bioaerosols in the biofiltration process and to make the treatment of VOCs by biotechnology more environmentally friendly. Additionally, the present work intends to increase people's awareness in regards to the control of bioaerosols, including microbial fragment present in bioaerosols.


Assuntos
Microbiologia do Ar/normas , Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Reatores Biológicos/microbiologia , Desinfecção/métodos , Aerossóis , Poluentes Atmosféricos/efeitos da radiação , Atmosfera/química , Biomassa , Química Verde , Humanos , Peróxido de Hidrogênio/química , Oxirredução , Ozônio/química , Raios Ultravioleta
19.
Adv Biochem Eng Biotechnol ; 173: 143-203, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32227251

RESUMO

The development and implementation of industrial biotechnology (IB) is associated with high expectations for reductions of environmental impacts and risks, particularly in terms of climate change and fossil resource depletion, positive socioeconomic effects, hopes for new competitive products and processes, and development in rural areas. However, not all products and processes are really advantageous with regard to sustainability criteria, and not all are economically successful and accepted by stakeholders. Sustainability and life cycle assessment can play an important role to assess IB products and processes, often accompanying development processes from the early stages onwards. Such assessments can identify key factors regarding sustainability criteria, enable a determination of both product and process performance, or aid in prospectively estimating such performance and its consequences. Thus, development processes, investment decisions, policymaking, and the communication with stakeholders can be supported. This contribution reviews the field of sustainability and life cycle assessment in IB. We explore relevant literature from a methodical and application perspective and categorise suitable methodologies, methods, and tools. We characterise IB from an assessment perspective and indicate challenges, discuss approaches to address these, and identify possible fields of future research. Thus, students, researchers, and practitioners in the field of IB will obtain an up-to-date overview, references to relevant fields of literature, and guidance for own studies in this important and fast-emerging topic.


Assuntos
Biotecnologia , Meio Ambiente , Indústrias , Previsões , Química Verde , Humanos
20.
Artigo em Inglês | MEDLINE | ID: mdl-32181694

RESUMO

In the past decade, Mexican coasts have received an enormous influx of macroalgae species, producing serious environmental and public health concerns. Here, we developed a green methodology to generate a new polymer from the lignin contained in the macroalgae. The methodology consists in lignin extraction-by-boiling and its subsequent polymerization with a laccase-like enzyme from the green algae Tetraselmis gracilis (Tg-laccase). Mass spectrometry revealed the presence of guaiacyl (G), p-hydroxyphenyl (H), and sinapyl alcohol as the main monolignols in the lignin from Sargassum sp. On the other hand, MALDI-TOF spectra shows an increase in the size of the lignin chain after enzymatic polymerization process with Tg-laccase. Besides, the characterization of the novel polymer -using 1H NMR, FTIR, SEC-FPLC, and UV/Vis- allowed establishing that during the polymerization process there is a decrease in the number of phenolic groups as well as loss of aromatic protons, which allowed proposing a polimerizacion mechanism. This methodology could be promising in the development of a new lignin-based polymer and would open a new direction for the environmental management of the macroalgae on the Mexican beaches.


Assuntos
Clorófitas/enzimologia , Química Verde/métodos , Lacase/química , Lignina/síntese química , Polimerização , Alga Marinha/química , Lignina/química , Peso Molecular , Fenóis/química
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