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1.
Z Naturforsch C J Biosci ; 76(7-8): 291-299, 2021 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-34218549

RESUMEN

In the present study, we investigated cytogenetic and oxidative [total antioxidant capacity (TAC), total oxidant status (TOS)] effects of methanol and water extracts of Cladonia chlorophaea (Flörke ex Sommerf.) Sprengel, Dermatocarpon miniatum (L.) W.Mann and Parmelia saxatilis (L.) Ach. on cultured human lymphocytes. In addition, different phenolic compounds in the extracts were quantified by high performance liquid chromatography (HPLC) analysis. As a result of HPLC analysis, methanol extracts of all lichen species tested had higher phenolic compounds. Likewise, methanol extracts of each lichen increased TAC levels in lymphocytes more than water extracts. The TOS levels of the cells treated with different concentrations (1-100 mg/L) of the extracts decreased due to the increasing concentration of the extracts. Genotoxicity experiments revealed that the tested lichen extracts did not significantly increase (p > 0.05) the level of genotoxicity on human peripheral lymphocyte culture compared to the negative control group. The results showed that C. chlorophaea, D. miniatum and P. saxatilis lichens, which were found to be a rich source of phenolic compounds, might be of interest in the pharmaceutical and food industries.


Asunto(s)
Extractos Celulares/farmacología , Análisis Citogenético/métodos , Líquenes/química , Linfocitos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Fenol/farmacología , Extractos Celulares/química , Extractos Celulares/aislamiento & purificación , Células Cultivadas , Cromatografía Líquida de Alta Presión , Aberraciones Cromosómicas/efectos de los fármacos , Rotura Cromosómica/efectos de los fármacos , Humanos , Líquenes/clasificación , Linfocitos/citología , Linfocitos/metabolismo , Pruebas de Micronúcleos/métodos , Estructura Molecular , Fenol/química , Fenol/aislamiento & purificación , Especificidad de la Especie
2.
Int J Biol Macromol ; 181: 734-742, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-33811934

RESUMEN

In the present study, two different modified starches; microporous starch (MPS) and cationic microporous starch (CMPS) were synthesized. The granules of MPS that distributed regularly were destroyed after the etherification reaction. The data depicted that the immobilization of horseradish peroxidase (HRP) on CMPS revealed highest immobilization efficiency (86%) at 100 mg of CMPS at pH = 6.0 and 100 units of enzyme. After 10 reuses of the CMPS-HRP, it retained 66% of initial activity. The soluble HRP showed broad pH optimum of 6.0-7.0, which changed to sharp pH = 6.0 for CMPS-HRP. Soluble-HRP and CMPS-HRP showed temperature optima at 30 °C and 40 °C, respectively. The CMPS-HRP showed high thermal stability up to 50 °C compared to the soluble HRP (40 °C). The Km values of soluble HRP and CMPS-HRP were 6.6 and 10.8 mM for H2O2 and 34 and 41.6 mM for guaiacol, respectively. CMPS-HRP showed higher affinity toward various substrates than the soluble-HRP. CMPS-HRP showed more resistance against heavy metals, urea, isopropanol, Triton X-100 and trypsin than soluble enzyme. The CMPS-HRP showed higher ability to remove phenol and p-chlorophenol compared to soluble-HRP.


Asunto(s)
Enzimas Inmovilizadas/metabolismo , Peroxidasa de Rábano Silvestre/metabolismo , Fenol/aislamiento & purificación , Almidón/química , Rastreo Diferencial de Calorimetría , Cationes , Concentración de Iones de Hidrógeno , Cinética , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier , Almidón/ultraestructura , Especificidad por Sustrato , Temperatura , Termogravimetría , Factores de Tiempo , Tripsina/metabolismo , Difracción de Rayos X
3.
Inflammation ; 44(5): 1762-1770, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33768402

RESUMEN

Fourteen constituents were recently isolated from the roots of Dendropanax dentiger with cyclooxygenase-2 (COX-2) inhibitory effects. However, the effect of 14 constituents on rheumatoid arthritis (RA) and their action mechanism remain unclear. The study aimed to explore the anti-RA effect and potential mechanism of these constituents in tumor necrosis factor α (TNF-α)-stimulated human RA fibroblast-like synoviocytes (MH7A cells). The cell viability, nitric oxide (NO) production, inflammatory cytokine levels, and protein expressions were measured by cell counting kit-8 (CCK-8), Griess reagent, ELISA, and Western blot assays, respectively. Results showed that 14 constituents (40 µM) have no cytotoxicity for MH7A cells. Among them, two phenols including 3,4-dimethoxyphenyl-1-O-α-L-rhamnopyranosyl-(1→6)-O-ß-D-glucopyranoside (DRG) and 3,4-dimethoxyphenol-ß-D-apiofuranosyl-(1→6)-ß-D-glucopyranoside (DAG) were shown to significantly inhibit the NO production with IC50 values of 5.25±0.34 and 5.35±0.31 µM, respectively. They also remarkably decreased the release of interleukin (IL)-2, 6, 8, and interferon (IFN)-γ, as well as prominently reduced the phosphorylation protein levels of p65, IkBα, AKT, and JNK at a concentration of 10 µM. Taken together, DRG and DAG could inhibit TNF-α-induced inflammatory response through blocking NF-kB/AKT/JNK signaling pathways in MH7A cells, thus could be promising against RA and other inflammation-related agents.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Glicósidos/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , FN-kappa B/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Medicamentos Herbarios Chinos/aislamiento & purificación , Glicósidos/aislamiento & purificación , Humanos , Mediadores de Inflamación/antagonistas & inhibidores , Mediadores de Inflamación/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , FN-kappa B/metabolismo , Fenol/aislamiento & purificación , Fenol/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo
4.
J Chromatogr A ; 1643: 462071, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33761435

RESUMEN

Mixed iron hydroxides (MIHs) modified with different amino-based polymeric materials, including aminopropyltriethoxysilane, polydopamine, diaminobenzoic acid, polyaniline, and polyphenylenediamine, were comparatively investigated as sorbents for the extraction of phenol compounds. Polyphenylenediamine-modified mixed iron hydroxides (MIH@PPDA) showed high adsorption capability for most target analytes. Its ferromagnetic behavior, with a magnetization of 17.38 emu g-1, was sufficient for subsequent use in magnetic solid-phase extraction (MSPE). The functional groups, morphology, and magnetic properties of this magnetic nanomaterial were investigated using Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, X-ray diffraction, and CHN analysis. High-performance liquid chromatography with a photodiode array detector was used to quantify phenol compounds. The experimental parameters affecting the efficiency of the entire MSPE process were optimized. Good linearity in the range of 0.5-1000 µg L-1 was obtained (depended on the compound). The detection and quantitation limits varied from 0.01 to 0.3 µg L-1 and 0.03 to 0.9 µg L-1, respectively. The enrichment factors for all phenol compounds were in the range of 80-285. The precision in terms of intra- and inter-day relative standard deviations were below 5.8% and 6.2%, respectively. The developed MSPE method was applied to analyze phenol compounds in diverse samples, including soil, drinking water, and fruit. Relative recoveries of 76.7-130.1% were obtained. The MIH@PPDA magneto-polymeric sorbent exhibits good stability and is reliable for a variety of phenol compounds.


Asunto(s)
Compuestos Férricos/química , Magnetismo , Fenol/análisis , Polímeros/química , Extracción en Fase Sólida/métodos , Adsorción , Cromatografía Líquida de Alta Presión , Agua Dulce/análisis , Concentración de Iones de Hidrógeno , Límite de Detección , Fenol/aislamiento & purificación , Reproducibilidad de los Resultados , Contaminantes del Suelo/análisis
5.
J Sci Food Agric ; 101(11): 4789-4798, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-33527437

RESUMEN

BACKGROUND: Cold brew coffee, based on cold extraction, is rapidly attracting consumers' preference worldwide. Low total solids yield and long extraction times (up to 24 h) are the main drawbacks of this process. Five different treatments were investigated: the traditional cold extraction method, freezing, lyophilization of coffee beans, use of chaotropic salt and reduced pressure extraction. The latter was optimized by applying a Box-Behnken design. Pressure, vacuum cycles, duration of each cycle and mass of ground coffee to water ratio were the optimization parameters. Yield, caffeine and phenol concentration were the response variables. RESULTS: Caffeine concentration and yield were significantly affected by vacuum cycles and by the combination of vacuum cycles and duration of each cycle. Validation of the derived quadratic models for each response variable was performed. Optimum values for highest extraction yield (22%) and phenol concentration as well as mass transfer coefficients of phenol and caffeine were also determined. CONCLUSIONS: Extraction under reduced pressure might be the best treatment for the acceleration of cold brew coffee extraction. © 2021 Society of Chemical Industry.


Asunto(s)
Cafeína/aislamiento & purificación , Coffea/química , Café/química , Manipulación de Alimentos/métodos , Fenol/aislamiento & purificación , Semillas/química , Cafeína/análisis , Manipulación de Alimentos/instrumentación , Fenol/análisis , Solventes/química , Temperatura
6.
Z Naturforsch C J Biosci ; 76(7-8): 317-327, 2021 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-33559461

RESUMEN

Phytochemical profiles of essential oil (EO), fatty acids, and n-hexane (CAH), diethyl ether (CAD), ethyl acetate (CAE) and methanol extracts (CAM) of Cota altissima L. J. Gay (syn. Anthemis altissima L.) were investigated as well as their antioxidant, anti-inflammatory, antidiabetic and antimicrobial activites. The essential oil was characterized by the content of acetophenone (35.8%) and ß-caryophyllene (10.3%) by GC-MS/FID. Linoleic and oleic acid were found as main fatty acids. The major constituents of the extracts were found to be 5-caffeoylquinic acid, 3,5-dicaffeoylquinic acid, isorhamnetin glucoside, quercetin and quercetin glucoside by LC-MS/MS. Antioxidant activities of the extracts were determined by scavenging of DPPH and ABTS free radicals. Also, the inhibitory effects on lipoxygenase and α-glucosidase enzymes were determined. Antimicrobial activity was evaluated against Gram positive, Gram negative bacteria and yeast pathogens. CAM showed the highest antioxidant activity against DPPH and ABTS radicals with IC50 values of 126.60 and 144.40 µg/mL, respectively. In the anti-inflammatory activity, CAE demonstrated the highest antilipoxygenase activity with an IC50 value of 105.40 µg/mL, whereas, CAD showed the best inhibition of α-glucosidase with an IC50 value of 396.40 µg/mL in the antidiabetic activity. CAH was effective against Staphylococcus aureus at MIC = 312.5 µg/mL. This is the first report on antidiabetic, anti-inflammatory and antimicrobial activities of different extracts of C. altissima.


Asunto(s)
Antiinfecciosos/farmacología , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Asteraceae/química , Hipoglucemiantes/farmacología , Fitoquímicos/farmacología , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Bacterias/clasificación , Bacterias/efectos de los fármacos , Compuestos de Bifenilo/metabolismo , Candida/efectos de los fármacos , Cromatografía Liquida/métodos , Flavonoides/química , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Hipoglucemiantes/química , Hipoglucemiantes/aislamiento & purificación , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Aceites Volátiles/farmacología , Oxidación-Reducción/efectos de los fármacos , Fenol/química , Fenol/aislamiento & purificación , Fenol/farmacología , Fitoquímicos/química , Fitoquímicos/aislamiento & purificación , Picratos/metabolismo , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Espectrometría de Masas en Tándem/métodos
7.
J Sep Sci ; 44(7): 1383-1390, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33471412

RESUMEN

Hypocrellins are anthraquinone that can act as excellent photosensitizers for photodynamic therapy. In the present work, we found that high-speed countercurrent chromatography using cupric chloride as a complexing agent effectively separated hypocrellins from Shiraia bambusicola extract. The optimal two-phase solvent system consisted of petroleum ether/ethyl acetate/methanol/water (7:3:5.5:4.5, v/v/v/v), with 0.01 mol/L cupric chloride in the lower phase at pH of 2.45. This lower phase served as the mobile phase, whereas the upper phase acted as the stationary phase. Employing a continuous separation mode, three continuous injections were found to allow the purification of 1.2 g of crude extract in approximately 12 h. Hypocrellin B (10.8 mg), hypocrellin A (16.2 mg), and hypocrellin C (15.6 mg) were obtained from this process. Simulation of complexation of hypocrellin A with divalent copper ion by computational chemistry calculations indicated that three pairs of hydroxyl and carbonyl groups in hypocrellin A had similar binding energies, and demonstrated that hypocrellin A and B owned different metal-to-ligand ratios as compared to hypocrellin C. These factors could modify the partitioning of these compounds in two-phase solvent system, and resulting in a suitable separation factor. This method would also be used to purify other anthraquinones from natural products.


Asunto(s)
Ascomicetos/química , Cobre/química , Perileno/análogos & derivados , Fenol/aislamiento & purificación , Quinonas/aislamiento & purificación , Distribución en Contracorriente , Estructura Molecular , Perileno/química , Perileno/aislamiento & purificación , Fenol/química , Quinonas/química
8.
Ecotoxicol Environ Saf ; 208: 111710, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396041

RESUMEN

The aim of the study was to investigate the sorption interactions between phenol and materials obtained from four different underground coal gasification (UCG) ex-situ simulations. These interactions are significant in terms of the impact of the UCG on the groundwater environment. Sorption parameters were determined for two sample types: raw coal mined from the coal-bed and then subjected to the gasification process; and char residue acquired from the cavity formed as a result of the UCG processes. Laboratory-scale tests were carried out using deionized water and aqueous solutions with increasing concentrations of phenol (from 50 mg/dm3 to 2000 mg/dm3) at 298 K. On the assumption of physical interactions (non-specific physisorption) and due to a nonlinear mass distribution of adsorbed substances as a function of equilibrium concentration, the Freundlich isotherm model was applied to describe adsorption phenomena. The isotherms have good fitting (R2 from 0.5716 to 0.9811). Relatively high percentage phenol removal efficiency was observed for all tested chars (from 17.0% to 99.8% for the 1.0-2.5 mm fraction and from 6.9% to 99.6% for the 10.0-12.5 mm fraction). Additionally, the sorption characteristics was used to evaluate the retardation coefficients. The largest delay in the organic pollutant migration in the environment around a UCG reactor occurs for phenol transport in the layer of the post-process char from 'Wesola' after 40 bar pressure experiment.


Asunto(s)
Carbón Mineral , Restauración y Remediación Ambiental/métodos , Fenol/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Calor , Minería , Modelos Teóricos , Fenol/química , Presión , Contaminantes Químicos del Agua/química
9.
Drug Des Devel Ther ; 14: 3301-3313, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32848368

RESUMEN

OBJECTIVE: To investigate the effect of erianin on tumor growth and immune response in human colorectal cancer cells (CRC). METHODS: The effect of erianin on tumor growth was determined by CCK8 and colony formation assay. Western blotting was used to evaluate the expression levels of relevant proteins and qRT-PCR was used to evaluate the mRNA level of the relevant gene. The transcriptional activity of ß-catenin was determined by dual-luciferase reporter assay. Cellular thermal shift assay was used to quantify drug-target interactions. The cell surface CD47 was assessed by flow cytometry. The enrichment of H3K27 acetyl marks on CD47 promoter was evaluated by chromatin immunoprecipitation assay. Phagocytosis assay was used to determine the phagocytic activity of macrophage. In vivo role of erianin was studied on xenograft models. RESULTS: We found that erianin significantly decreased cell survival, colony formation, induced cell cycle arrest, and led to cell apoptosis in SW480 and HCT116 cells. Mechanism analysis demonstrated that erianin inhibited the nuclear translocation and transcriptional activity of ß-catenin, which might result from erianin-ß-catenin interaction. In addition, the downstream gene expressions, such as c-Myc and cyclin D1, was decreased. More interestingly, erianin decreased the expression of CD47 by regulating H3K27 acetyl marks enrichment on CD47 promoter. Consequently, macrophage-mediated phagocytosis was increased. Our in vivo experiments further confirmed the inhibitory effect of erianin on tumor growth. CONCLUSION: In summary, erianin could inhibit CRC cells growth and promoted phagocytosis, which suggested erianin as a potential therapeutic strategy for CRC patients.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Bibencilos/farmacología , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Fagocitosis/efectos de los fármacos , Fenol/farmacología , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Apoptosis/efectos de los fármacos , Bibencilos/química , Bibencilos/aislamiento & purificación , Puntos de Control del Ciclo Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neoplasias Colorrectales/patología , Dendrobium/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , Estructura Molecular , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Fenol/química , Fenol/aislamiento & purificación , Relación Estructura-Actividad , Células Tumorales Cultivadas
10.
Sci Rep ; 10(1): 13669, 2020 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-32792538

RESUMEN

Wild mushroom foraging involves a high risk of unintentional consumption of poisonous mushrooms which is a serious health concern. This problem arises due to the close morphological resemblances of toxic mushrooms with edible ones. The genus Inocybe comprises both edible and poisonous species and it is therefore important to differentiate them. Knowledge about their chemical nature will unambiguously determine their edibility and aid in an effective treatment in case of poisonings. In the present study, the presence of volatile toxic metabolites was verified in Inocybe virosa by gas chromatography. Methyl palmitate, phenol, 3,5-bis (1,1-dimethyl ethyl) and phytol were the identified compounds with suspected toxicity. The presence of the toxin muscarine was confirmed by liquid chromatography. The in vitro study showed that there was negligible effect of the digestion process on muscarine content or its toxicity. Therefore, the role of muscarine in the toxicity of Inocybe virosa was studied using a bioassay wherein metameters such as hypersalivation, immobility, excessive defecation, heart rate and micturition were measured. Administration of muscarine resulted in an earlier onset of symptoms and the extract showed a slightly stronger muscarinic effect in comparison to an equivalent dose of muscarine estimated in it. Further, the biological fate of muscarine was studied by pharmacokinetics and gamma scintigraphy in New Zealand white rabbits. Significant amount of the toxin was rapidly and effectively concentrated in the thorax and head region. This study closely explains the early muscarinic response such as miosis and salivation in mice. By the end of 24 h, a relatively major proportion of muscarine administered was accumulated in the liver which stands as an explanation to the hepatotoxicity of Inocybe virosa. This is one of the rare studies that has attempted to understand the toxic potential of muscarine which has previously been explored extensively for its pharmaceutical applications.


Asunto(s)
Agaricales/química , Muscarina/toxicidad , Tórax/química , Toxinas Biológicas/aislamiento & purificación , Animales , Química Encefálica , Línea Celular , Supervivencia Celular/efectos de los fármacos , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Ratones , Muscarina/administración & dosificación , Muscarina/aislamiento & purificación , Palmitatos/aislamiento & purificación , Fenol/aislamiento & purificación , Fitol/aislamiento & purificación , Conejos , Toxinas Biológicas/química
11.
J Oleo Sci ; 69(7): 767-770, 2020 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-32522942

RESUMEN

The volatile components produced by Leptolejeunea elliptica (Lejeuneaceae), which is a liverwort grown on the leaves of tea (Camellia sinensis), were collected and analyzed using headspace solid-phase microextraction-gas chromatography/mass spectrometry (HS-SPME-GC/MS). 1-Ethyl-4-methoxybenzene (1), 1-ethyl-4-hydroxybenzene (2), and 1-acetoxy-4-ethylbenzene (3) were identified as the major components together with several other phenolic compounds, including 1,2-dimethoxy-4-ethylbenzene, and 4-ethylguaiacol in addition to sesquiterpene hydrocarbons, such as α-selinene, ß-selinene, ß-elemene, and ß-caryophyllene. GC/Olfactometry showed the presence of linalool, acetic acid, isovaleric acid, trans-methyl cinnamate, and trans-4,5-epoxy-(2E)-decenal, as the volatile components produced by L. elliptica.


Asunto(s)
Hepatophyta/metabolismo , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/aislamiento & purificación , Ácido Acético/análisis , Ácido Acético/aislamiento & purificación , Anisoles/análisis , Anisoles/aislamiento & purificación , Derivados del Benceno/análisis , Derivados del Benceno/aislamiento & purificación , Camellia sinensis , Cromatografía de Gases y Espectrometría de Masas/métodos , Japón , Olfatometría , Fenol/análisis , Fenol/aislamiento & purificación , Fenoles/análisis , Fenoles/aislamiento & purificación , Sesquiterpenos Policíclicos/análisis , Sesquiterpenos Policíclicos/aislamiento & purificación , Sesquiterpenos/análisis , Sesquiterpenos/aislamiento & purificación , Microextracción en Fase Sólida/métodos
12.
Int J Biol Macromol ; 156: 94-102, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32289419

RESUMEN

VS2 spheres and VS2 sheets with doped compositions (Mo, Ag and graphite) were successfully prepared by one-step hydrothermal method and characterized by different techniques including X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N2 adsorption isotherms. Catalysts were applied for the depolymerization of alkali lignin. VS2 spheres exhibited lower yield of degraded lignin and bio-oil than those with VS2 sheets and VS2 flowers heated to 250 °C and held for 1.5 h with 2.0 MPa H2. The catalytic depolymerization performance was markedly affected by the dopant in the VS2 sheets, with the highest degraded lignin yield of 81.22%, achieved over 5 wt% Ag-VS2 at 290 °C under 2.0 MPa H2 for 1.5 h, yielding 61.23% bio-oil. The VS2-based catalysts show excellent selectivity in the interruption of the lignin structure and target production of bio-oil. The bio-oil showed that the relevant contents of a phenolic-type compound changes significantly according to the dopant in the VS2 catalyst.


Asunto(s)
Lignina/química , Lignina/aislamiento & purificación , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificación , Polifenoles/química , Polifenoles/aislamiento & purificación , Compuestos de Vanadio/química , Álcalis/química , Catálisis , Cromatografía de Gases y Espectrometría de Masas , Grafito/química , Calor , Lignina/análisis , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Molibdeno/química , Fenol/química , Fenol/aislamiento & purificación , Aceites de Plantas/análisis , Polifenoles/análisis , Plata/química , Espectroscopía Infrarroja por Transformada de Fourier , Compuestos de Vanadio/análisis , Difracción de Rayos X
13.
Bioelectrochemistry ; 134: 107527, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32279033

RESUMEN

Co-metabolism is one of the effective approaches to increase the removal of refractory pollutants in microbial fuel cells (MFCs), but studies on the links between the co-substrates and biodegradation remain limited. In this study, four external carbon resources were used as co-substrates for phenol removal and power generation in MFC. The result demonstrated that acetate was the most efficient co-substrate with an initial phenol degradation of 78.8% and the voltage output of 389.0 mV. Polarization curves and cyclic voltammogram analysis indicated that acetate significantly increased the activity of extracellular electron transfer (EET) enzyme of the anodic microorganism, such as cytochrome c OmcA. GC-MS and LC-MS results suggested that phenol was biodegraded via catechol, 2-hydroxymuconic semialdehyde, and pyruvic acid, and these intermediates were reduced apparently in acetate feeding MFC. The microbial community analysis by high-throughput sequencing showed that Acidovorax, Geobacter, and Thauera were predominant species when using acetate as co-substrate. It can be concluded that the efficient removal of phenol was contributed to the positive interactions between electrochemically active bacteria and phenolic degradation bacteria. This study might provide new insight into the positive role of the co-substrate during the treatment of phenolic wastewater by MFC.


Asunto(s)
Fuentes de Energía Bioeléctrica , Fenol/metabolismo , Electroquímica , Electrodos , Contaminantes Ambientales/aislamiento & purificación , Contaminantes Ambientales/metabolismo , Fenol/aislamiento & purificación
14.
Artículo en Inglés | MEDLINE | ID: mdl-32012816

RESUMEN

Adsorption by activated carbons (AC) is an effective option for phenolic wastewater treatment. Three commercial AC, including coal-derived granular activated carbons (GAC950), coal-derived powdered activated carbons (PAC800), and coconut shell-derived powdered activated carbons (PAC1000), were utilized as adsorbent to study its viability and efficiency for phenol removal from wastewater. Pseudo-first order, pseudo-second order, and the Weber-Morris kinetic models were used to find out the kinetic parameters and mechanism of adsorption process. Further, to describe the equilibrium isotherms, the experimental data were analyzed by the Langmuir and Freundlich isotherm models. According to the experimental results, AC presented a micro/mesoporous structure, and the removal of phenol by AC was affected by initial phenol concentration, contact time, pH, temperature, and humic acid (HA) concentration. The pseudo-second order kinetic and Langmuir models were found to fit the experimental data very well, and the maximum adsorption capacity was 169.91, 176.58, and 212.96 mg/g for GAC950, PAC800, and PAC1000, respectively, which was attributed to differences in their precursors and physical appearance. Finally, it was hard for phenol to be desorbed in a natural environment, which confirmed that commercial AC are effective adsorbents for phenol removal from effluent wastewater.


Asunto(s)
Carbón Orgánico/química , Fenol/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Concentración de Iones de Hidrógeno , Cinética
15.
Chemosphere ; 239: 124708, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31505442

RESUMEN

The discharge of phenol, a harmful pollutant, in the environment poses a threat to human health. With the rapid urbanization and industrialization of the land, there is a pressing need to find new technologies and efficient adsorption materials to address phenol contamination. As a potential adsorbent candidate, sepiolite (SEP) has garnered much interest owing to its large specific surface area, and excellent adsorption performance and biocompatibility. Herein, nanocomposite CESEP/ZIF-8, consisting of zeolite imidazole framework (ZIF-8) and hydrochloric acid-modified SEP (CESEP), was prepared and examined toward the adsorption of phenol. Adsorption equilibrium was achieved within 150 min at initial phenol solution concentrations of 10 and 20 mg/L. However, complete removal was not achieved. Accordingly, biodegradation was introduced. Microorganism Pseudomonas putida was immobilized onto CESEP/ZIF-8, which afforded synergistic adsorption and biodegradation action. Phenol at solution concentrations of 10 and 20 mg/L was effectively removed within 13 and 24 h, respectively (as opposed to 21 and 36 h when phenol was removed in the presence of free Pseudomonas putida solely). The synergistic physical-biological treatment presented herein is expected to have great potential in the field of wastewater treatment.


Asunto(s)
Biodegradación Ambiental , Imidazoles/química , Nanocompuestos/química , Fenol/aislamiento & purificación , Pseudomonas putida/metabolismo , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Zeolitas , Adsorción , Cinética , Fenol/metabolismo , Fenoles/aislamiento & purificación , Fenoles/metabolismo , Aguas Residuales/química , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua/normas
16.
Chemosphere ; 238: 124621, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31454740

RESUMEN

Present study prepared a new magnetic and thermo dual-responsive core-shell nanomaterial (Fe@SiO2@poly(N-isopropylacrymide-co-methacrylic acid, Fe@SiO2@PNIPAM-co-MAA), which was characterized by transmission electron microscopy and X-ray diffraction techniques. The new nanomaterials integrated with the magnetism of nanoscale zero valent iron material and thermo-response of the copolymers, and were utilized to investigate the adsorption capacity for typical phenols such as bisphenol A, phenol and hydroquinone from water samples, and the results showed that the magnetic and thermo dual-responsive core-shell nanomaterial exhibited good adsorption ability to typical phenols. Based on these, a sensitive method was developed for the determination of bisphenol A, phenol and hydroquinone using as-prepared magnetic nanoparticles as the magnetic solid phase extraction sorbent prior to high performance liquid chromatography coupled with variable wavelength detection. Under the optimal conditions, linear linearity was obtained over the range of 0.1-500 µg L-1 with the correlation coefficients (r2) above 0.996. The detection limits of three analytes were in the range of 0.019-0.031 µg L-1, and the precisions were all less than 4.8% (n = 6). The developed method was evaluated with real water samples and excellent spiked recoveries in the range of 94.0-105.4% were achieved. These results indicated that the proposed method was a robust analytical tool and a useful alternative for routine analysis of such pollutants.


Asunto(s)
Compuestos de Bencidrilo/aislamiento & purificación , Hidroquinonas/aislamiento & purificación , Magnetismo , Nanoestructuras/química , Fenol/aislamiento & purificación , Fenoles/aislamiento & purificación , Extracción en Fase Sólida/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Compuestos de Bencidrilo/análisis , Hidroquinonas/análisis , Fenol/análisis , Fenoles/análisis , Temperatura , Contaminantes Químicos del Agua/análisis
17.
Chemosphere ; 239: 124714, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31499309

RESUMEN

Enhanced mineralization of phenol in brines with high chloride content was investigated by employing an electrochemical advanced oxidation treatment that couples anodic oxidation, electrochlorination and electro-Fenton in a single process. Experimental work was carried out in a pilot scale unit with an undivided plate-and-frame cell equipped with a boron-doped diamond anode and a carbon-PTFE gas diffusion electrode as cathode, in batch recirculation mode. The effects of operating conditions on phenol degradation, including current density, air flow rate, water feed flow rate, Fe2+ dosage and pH as well as of the water matrix, were evaluated. Applied current exhibited the greatest effect on phenol degradation/mineralization efficiency. Complete degradation of phenol (of initial concentration 50 mg L-1) was achieved under the near-optimum operating conditions (40 mA cm-2, pH 7, 0.4 m3 h-1 water circulation rate) within 30 min. Both air flow rate and Fe2+ dosage did not show a measurable impact on phenol removal. However, increasing the chloride content of water significantly improved the efficiency of treatment due to the enhanced indirect oxidation by the electrogenerated chlorine. Several trihalomethane intermediates (chloroform, bromodichloromethane) and chlorinated/brominated phenol byproducts forming during treatment, were eliminated after 60 min of processing time.


Asunto(s)
Técnicas Electroquímicas/métodos , Fenol/aislamiento & purificación , Salinidad , Contaminantes Químicos del Agua , Cloro/farmacología , Electrodos , Peróxido de Hidrógeno/química , Oxidación-Reducción , Proyectos Piloto , Aguas Salinas , Contaminantes Químicos del Agua/aislamiento & purificación
18.
Int J Biol Macromol ; 140: 949-958, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31445147

RESUMEN

In this study, hydrazine treated acrylic fabrics (polyacrylonitrile, PAN) activated with cyanuric chloride was developed as supporting material for horseradish peroxidase (HRP) immobilization. The immobilization of HRP onto the modified supporting material was achieved after being end-over-end incubated for 12 h. Field emission scanning electron microscopy and Fourier-transform infrared spectroscopy techniques were used to confirm the successful immobilization. Reusability experiment was performed to estimate the ability of the immobilized HRP to recover the reaction medium, in which it was observed to retain 78% of its original activity after 10 cycles. Relative to the soluble HRP, the optimum pH and temperature for the immobilized HRP were shifted to 7-7.5 and 50 °C, respectively. The kinetic parameters of guaiacol and H2O2 for the immobilized HRP were determined to be Km/Vmax = 57.61, 11.35 and Kcat/Km = 1.87, 1.86, respectively, while the values for the free form were Km/Vmax = 41.49, 6.23 and Kcat/Km = 1.87, 1.86, respectively. Compared to the soluble form, the immobilized HRP exhibited higher resistance toward metal ions and some organic solvents. For an application perspective. The immobilization of HRP using this procedure has the potential to be used for industrial application and wastewater treatment.


Asunto(s)
Resinas Acrílicas/química , Enzimas Inmovilizadas/metabolismo , Peroxidasa de Rábano Silvestre/metabolismo , Fenol/aislamiento & purificación , Triazinas/farmacología , Estabilidad de Enzimas/efectos de los fármacos , Hidrazinas/química , Hidrazinas/farmacología , Concentración de Iones de Hidrógeno , Cinética , Metales/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Especificidad por Sustrato/efectos de los fármacos , Temperatura , Factores de Tiempo , Triazinas/química
19.
Int J Biol Macromol ; 138: 349-358, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31295480

RESUMEN

Cigarette smoke contains a lot of harmful chemicals which cause different diseases like cancer, heart disease, bronchitis and ulcer etc. Ammonia and phenol are among those chemicals which cause cancer, fibrosis, respiratory disorder and pneumonia. So, to remove ammonia and phenol from cigarette smoke, five different types of carboxymethyl starch-g-polyacrylic acids (CMS-g-PAAs) were synthesized by using different initiators, different mole ratio of acrylic acid to CMS anhydroglucose unit (AGU) and different amount of water. Three types of modified CMSs, CMS-g-PAA1, CMS-g-PAA3 and CMS-g-PAA4 were selected for further characterization and application for ammonia and phenol adsorption. The 1H NMR and FT-IR spectroscopy confirmed the successful grafting of PAA on CMS. Crystallinity of CMS and three modified CMSs was checked by their XRD analysis. The XRD analysis showed that CMS had crystalline nature which was lost after modification. The thermal properties of CMS and the modified samples were checked by TGA and DTG which also gave information about the successful grafting on PAA on CMS. Finally the modified CMSs were further used for the adsorption applications of ammonia and phenol from the gaseous stream. It was found that CMS-g-PAA4 showed the highest adsorption efficiency towards ammonia (0.352 mmol/g) and phenol (0.18 mmol/g).


Asunto(s)
Resinas Acrílicas/química , Amoníaco/química , Amoníaco/aislamiento & purificación , Fenol/química , Fenol/aislamiento & purificación , Almidón/análogos & derivados , Adsorción , Técnicas de Química Sintética , Análisis Costo-Beneficio , Contaminantes Ambientales/química , Contaminantes Ambientales/aislamiento & purificación , Tecnología Química Verde , Almidón/química
20.
J Biol Inorg Chem ; 24(7): 943-959, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31359184

RESUMEN

Immobilized tyrosinase onto the functionalized nanoparticles with the ability to be reused easily in different reaction cycles to degrade phenolic compounds is known as a substantial challenge, which can be overcome through surface modification of the particles via proper chemical groups. Herein, the synthesis and silica coating of superparamagnetic nanoparticles using a simple procedure as well as their potential for tyrosinase immobilization were demonstrated. Therefore, N-[3-(trimethoxysilyl)propyl]ethylenediamine was used to functionalize the silica-coated nanoparticles with amine groups. Then, the ethylenediamine functionalized magnetic nanoparticles (EMNPs) were suspended in a solution containing tetrahydrofuran and cyanuric chloride (as an activating agent) to modify nanocarriers. To immobilize enzyme, a mixture of tyrosinase and cyanuric chloride functionalized magnetic nanoparticle (Cyc/EMNPs) was shaken at room temperature. The particles were characterized by EDX, TGA, SEM, FTIR, and TEM. As a result, the successful functionalization of the magnetic nanoparticles and covalent attachment of tyrosinase onto the Cyc/EMNPs were confirmed. The fabricated nano-biocatalyst particles were semi-spherical in shape. The immobilized tyrosinase (Ty-Cyc/EMNPs) exhibited remarkable reusability of six consecutive reaction cycles while no considerable loss of activity was observed for the first three cycles. Moreover, the excellent stability of the biocatalyst at different temperatures and pHs was proved. The Ty-Cyc/EMNPs with interesting features are promising for practical applications in biosensor development and wastewater treatment.


Asunto(s)
Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Enzimas , Etilenodiaminas/química , Nanopartículas de Magnetita/química , Monofenol Monooxigenasa/química , Monofenol Monooxigenasa/metabolismo , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Fenol/aislamiento & purificación , Fenol/metabolismo , Temperatura
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