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1.
Immunotherapy ; 13(5): 397-407, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33557591

RESUMEN

Background: This study assesses the feasibility of producing hyperimmune anti-COVID-19 intravenously administrable immunoglobulin (C-IVIG) from pooled convalescent plasma (PCP) to provide a safe and effective passive immunization treatment option for COVID-19. Materials & methods: PCP was fractionated by modified caprylic acid precipitation followed by ultrafiltration/diafiltration to produce hyperimmune C-IVIG. Results: In C-IVIG, the mean SARS-CoV-2 antibody level was found to be threefold (104 ± 30 cut-off index) that of the PCP (36 ± 8.5 cut-off index) and mean protein concentration was found to be 46 ± 3.7 g/l, comprised of 89.5% immunoglobulins. Conclusion: The current method of producing C-IVIG is feasible as it uses locally available PCP and simpler technology and yields a high titer of SARS-CoV-2 antibody. The safety and efficacy of C-IVIG will be evaluated in a registered clinical trial (NCT04521309).


Asunto(s)
Anticuerpos Antivirales/aislamiento & purificación , Inmunoglobulinas Intravenosas/aislamiento & purificación , /inmunología , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/uso terapéutico , Caprilatos/química , Fraccionamiento Químico , Humanos , Inmunización Pasiva , Inmunoglobulinas Intravenosas/inmunología , Inmunoglobulinas Intravenosas/uso terapéutico
2.
Chemosphere ; 269: 129327, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33385674

RESUMEN

The extensive hydrolysis of tetravalent actinides leads to polynuclear formations through oxygen bridging facilitating the formation of colloids as end products. The pH, ionic strength has phenomenal effects on Thorium colloids formation. The quantitative estimation of colloids facilitates the fraction of soluble fraction into ionic, polymeric and colloidal forms of thorium. The colloids accountability and precipitate characterization explains the discrepancies in estimated solubility limits. The supernatants of long equilibrated (∼3 years) saturated thorium solution under various pH (5- 11) and ionic strengths (0-3 M NaClO4) were analysed by Inductively Coupled Plasma Mass Spectrometer (ICP-MS) and Ion Chromatography (IC) to determine total and ionic thorium respectively. Laser Induced Breakdown Detection (LIBD) was employed to determine the colloid size and concentrations. The precipitates were characterized by calorimetry and XRD to determine the solubility limiting phase. The results of pH, IC, ICP-MS, and LIBD measurements on the aged thorium samples are discussed with regard to the mechanism of the formation of thorium colloids. The results revealed the formation of colloids having particle size (10-40 nm) at concentrations (109-1011 particles/mL). The colloids accountancy resulted in estimated solubility products to 2-4 orders lower than their inclusion as soluble thorium. The soluble thorium was fractionated quantitatively into ionic, polymeric and colloidal forms of thorium. The precipitates formed are found to be semi amorphous.


Asunto(s)
Coloides , Torio , Fraccionamiento Químico , Coloides/análisis , Tamaño de la Partícula , Solubilidad , Torio/análisis
3.
Sensors (Basel) ; 21(2)2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33445458

RESUMEN

The electronic tongue (e-tongue) is an advanced sensor-based device capable of detecting low concentration differences in solutions. It could have unparalleled advantages for meat quality control, but the challenges of standardized meat extraction methods represent a backdrop that has led to its scanty application in the meat industry. This study aimed to determine the optimal dilution level of meat extract for e-tongue evaluations and also to develop three standardized meat extraction methods. For practicality, the developed methods were applied to detect low levels of meat adulteration using beef and pork mixtures and turkey and chicken mixtures as case studies. Dilution factor of 1% w/v of liquid meat extract was determined to be the optimum for discriminating 1% w/w, 3% w/w, 5% w/w, 10% w/w, and 20% w/w chicken in turkey and pork in beef with linear discriminant analysis accuracies (LDA) of 78.13% (recognition) and 64.73% (validation). Even higher LDA accuracies of 89.62% (recognition) and 68.77% (validation) were achieved for discriminating 1% w/w, 3% w/w, 5% w/w, 10% w/w, and 20% w/w of pork in beef. Partial least square models could predict both sets of meat mixtures with good accuracies. Extraction by cooking was the best method for discriminating meat mixtures and can be applied for meat quality evaluations with the e-tongue.


Asunto(s)
Nariz Electrónica/normas , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Aves de Corral , Carne Roja/análisis , Animales , Fraccionamiento Químico/métodos , Pollos , Culinaria , Análisis de los Alimentos/normas , Alimentos Congelados/análisis , Análisis de los Mínimos Cuadrados , Modelos Estadísticos , Pavos , Agua/química
4.
Viruses ; 13(1)2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33451082

RESUMEN

Viruses are highly abundant, diverse, and active components of marine environments. Flow cytometry has helped to increase the understanding of their impact on shaping microbial communities and biogeochemical cycles in the pelagic zone. However, to date, flow cytometric quantification of sediment viruses is still hindered by interference from the sediment matrix. Here, we developed a protocol for the enumeration of marine sediment viruses by flow cytometry based on separation of viruses from sediment particles using a Nycodenz density gradient. Results indicated that there was sufficient removal of background interference to allow for flow cytometric quantification. Applying this new protocol to deep-sea and tidal-flat samples, viral abundances enumerated by flow cytometry correlated well (R2 = 0.899) with counts assessed by epifluorescence microscopy over several orders of magnitude from marine sediments of various compositions. Further optimization may be needed for sediments with low biomass or high organic content. Overall, the new protocol enables fast and accurate quantification of marine sediment viruses, and opens up the options for virus sorting, targeted viromics, and single-virus sequencing.


Asunto(s)
Citometría de Flujo/métodos , Sedimentos Geológicos/virología , Agua de Mar , Virus , Microbiología del Agua , Fraccionamiento Químico , Dermoscopía , Carga Viral , Virus/aislamiento & purificación
5.
J Environ Manage ; 282: 111553, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33413975

RESUMEN

Soils with continuous application of swine slurry (SS) may present high phosphorus (P) content and high risk for environmental pollution. The aim of this study was to characterize the forms of phosphorus accumulation in 15 fields with increasing degrees of P saturation (DPS) in a watershed with a high density of swine farming. Soil samples collected from 0 to 10 cm were chemically characterized for water soluble phosphorus (WSP), DPS, Hedley chemical fractionation, and chemical speciation by P K-edge XANES. WSP increased linearly to a value of 137% of DPS, with subsequent stabilization at 2.7 mg kg-1. Only the inorganic fractions of the chemical fractionation changed with increasing DPS. Phosphorus forms considered labile increased up to 144% of DPS, with subsequent stabilization. The moderately labile fraction 0.1 M NaOH and non-labile 1 M HCl increased exponentially. Phosphorus K-edge XANES analysis demonstrated that P associated to apatite, amorphous aluminum minerals, and goethite were the main forms of P found and only the latter had a correlation with DPS (-0.57*). With increasing DPS, there are changes in the dynamics of P in the soil, with a reduction in forms associated to Fe and an increase in forms linked to Al. The forms linked to Al buffer the WSP and are recovered in the first inorganic fractions of the Hedley chemical fractionation.


Asunto(s)
Fósforo , Suelo , Agricultura , Animales , Fraccionamiento Químico , Porcinos
6.
Food Chem ; 346: 128896, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33421901

RESUMEN

Type of the wood used for the aging highly influences the quality of alcoholic beverages. In this research we explored the potential of cyclic voltammetry (CV) and differential pulse voltammetry (DPV) to establish fingerprints characteristic for each wood and to enable determining the type of the wood used in the aging process. Eleven different wood samples were used to prepare three different types of spirits during 15 months. The highest extraction rate was obtained during the first month, while further aging was followed with almost constant amount of extracted polyphenols. Black locust, myrobalan plum, and mulberry extracts were discriminated from the spirits aged in oak and wild cherry wood when statistical analysis was applied. Although clear classification of all samples was not achieved, this long term study demonstrated a potential of both CV and DPV for differentiating wood species used in the aging, hence in the quality control of spirits.


Asunto(s)
Bebidas Alcohólicas/análisis , Fraccionamiento Químico/métodos , Solventes/química , Madera/química , Frutas/química , Tecnología Química Verde , Factores de Tiempo , Madera/microbiología
7.
Ecotoxicol Environ Saf ; 210: 111865, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33418154

RESUMEN

Cd contamination in rice grains has become a topic of great concern because of the high health risks associated with the long-term consumption of Cd-contaminated rice. Identification of Cd sources in rice grains by scientific methods is important for controlling heavy metal pollution and protecting human health. Here, the Cd concentrations and Cd isotopic compositions of rice plants (root, stem, leaf, and grain) and topsoil, and possible pollution sources (agricultural fertilizers, industrial dust, and automobile exhaust) were analyzed using an instrument of inductively coupled plasma mass spectrometry (ICP-MS) and multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). The results showed variations in the Cd isotopes of different components of rice plants and the fractionation coefficient of rice grains relative to topsoil (Δ114/110Cdrice grains-topsoil = 0.25‰). The contributions of pollution sources to rice grains were realized by combining the Cd isotopic composition with an isotopic mixing model (Isosource). The analysis showed that all three possible pollution sources contributed to the Cd in the rice grains in the field, the average Cd contribution of industrial dust, agricultural fertilizers and automobile exhaust was 87%, 9%, and 4%, respectively. Our study provides a feasible method for the identification of pollution sources of Cd in rice grains at the field scale and demonstrates that Cd isotopic composition is one of the powerful tools to trace the pollution sources of Cd in crops.


Asunto(s)
Cadmio/análisis , Grano Comestible/química , Oryza , Contaminantes del Suelo/análisis , Cadmio/química , Fraccionamiento Químico , Polvo , Monitoreo del Ambiente , Fertilizantes , Humanos , Industrias , Isótopos/análisis , Emisiones de Vehículos
8.
Food Chem ; 340: 127918, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-32889209

RESUMEN

The study was an attempt to compare batch and circulating processes for polyphenols extraction from pomelo peels by liquid-phase pulsed discharge (LPD) in order to assess the extraction efficiency of the two processes. Response surface methodology was used to optimize batch (8-12 kV discharge voltage, 30-50 mL/g liquid to solid ratio and 2-4 min extraction time) and circulating (8-12 kV discharge voltage, 30-50 mL/g liquid to solid ratio and 20-40 mL/min flow rate) extractions. The highest polyphenols yield was 2.50 ± 0.02% at 42.2 mL/g, 12 kV and 4 min in batch extraction, while circulating extraction produced the most polyphenols (2.42 ± 0.01%) at 43.7 mL/g, 10.4 kV and 27.6 mL/min. The results showed that batch extraction achieved much greater yields than circulating extraction with lower-cost equipment. Therefore, batch extraction was a promising technology for the separation of high value-added products from pharmaceuticals and fine chemicals.


Asunto(s)
Fraccionamiento Químico/métodos , Citrus/química , Frutas/química , Polifenoles/aislamiento & purificación , Fraccionamiento Químico/instrumentación , Industria de Procesamiento de Alimentos/instrumentación , Industria de Procesamiento de Alimentos/métodos
9.
Food Chem ; 340: 127979, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-32920303

RESUMEN

Vitamin D deficiency has been linked to various diseases, but could be rectified via fortified food stuffs or supplementation. In this study 39 different hydrophobic deep eutectic solvents were evaluated for green extraction of ergosterol from mushroom. Extraction parameters (e.g. time, solvent volume) were optimized using response surface methodology (RSM) and a maximum extraction yield of 6995.00 µg ergosterol/g dry weight mushroom was attained with menthol: pyruvic acid. The extracted ergosterol was purified using a novel methodology and the extraction solvent was reused for six cycles, while retaining extraction efficiency (up to 28%). The ergosterol was exposed to ultra-violet radiation for conversion to ergocalciferol (vitamin D2) resulting in a yield of ergocalciferol that was equivalent to 2142.01 µg/g dry weight mushroom.


Asunto(s)
Agaricus/química , Ergosterol/aislamiento & purificación , Mentol/química , Fraccionamiento Químico/métodos , Ergocalciferoles/química , Ergosterol/química , Industria de Procesamiento de Alimentos/métodos , Interacciones Hidrofóbicas e Hidrofílicas , Solventes/química , Rayos Ultravioleta
10.
Chemosphere ; 263: 127931, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33297015

RESUMEN

Artificially contaminated soil is often used in laboratory experiments as a substitute for actual field contaminated soils. In the preparation and use of laboratory contaminated soils, questions remain as to how much and how long metals remain in labile form and in their oxidation state during the contamination process. Therefore, the objectives of this study were to determine if the speciation of added contaminants can be retained in the original form and to observe the change in lability of each element with aging time. In this study, natural soil was artificially polluted with five redox-sensitive toxic elements in their oxidized or reduced forms, i.e., As(III)/As(V), Sb(III)/Sb(V), Cr(III)/Cr(VI), Mo(VI), and W(V). Metal distribution was measured in progressive chemical fractionation using sequential extraction methods in contaminated soils after 3, 100, and 300 days of aging. The results indicated that the more strongly bound fraction of metals increased by day 100; whereas the fractions were not significantly different from those in the 300-day-aged soil. Among five metals, the ratio of weakly-bound fractions remained highest in As- and lowest in Cr-contaminated soils. The W(VI)-contaminated soil showed strong sorption without changes in speciation during aging. The oxidized or reduced metal species converged to occur as a single species under given soil conditions, regardless of the initial form of metal used to spike the soil. Both As and Sb existed as their oxidized form while Cr existed as its reduced form. The results of this study may provide a useful and practical guideline for artificial soil contamination.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Fraccionamiento Químico , Contaminación Ambiental , Metales Pesados/análisis , Oxidación-Reducción , Suelo , Contaminantes del Suelo/análisis
11.
Bioresour Technol ; 319: 124144, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32979595

RESUMEN

Domestic wastewater (DWW) can be preconcentrated to facilitate energy recovery via anaerobic digestion (AD), following the concept of "carbon capture-anaerobic conversion-bioenergy utilization." Herein, real DWW and preconcentrated domestic wastewater (PDWW) were both subject to particle size fractionation (0.45-2000 µm). DWW is a type of low-strength wastewater (average COD of 440.26 mg/L), wherein 60% of the COD is attributed to the substances with particle size greater than 0.45 µm. Proteins, polysaccharides, and lipids are the major DWW components. PDWW with a high COD concentration of 2125.89 ± 273.71 mg/L was obtained by the dynamic membrane filtration (DMF) process. PDWW shows larger proportions of settleable and suspended fractions, and accounted for 63.4% and 33.8% of the particle size distribution, and 52.4% and 32.2% of the COD, respectively. The acceptable biomethane potential of 262.52 ± 11.86 mL CH4/g COD of PDWW indicates bioenergy recovery is feasible based on DWW preconcentration and AD.


Asunto(s)
Eliminación de Residuos Líquidos , Aguas Residuales , Anaerobiosis , Bioensayo , Reactores Biológicos , Fraccionamiento Químico , Tamaño de la Partícula
12.
Food Chem ; 338: 127829, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-32818867

RESUMEN

Nine ciders obtained by cryo-extraction were analysed for chemical, olfactometric and sensory characteristics. Three types of ice apple juices and three autochthonous yeast strains were evaluated. The quantitative volatile profile is mainly influenced by the apple juice. Regarding the olfactometric profiles of the ice ciders, 23 odorants not previously found in Spanish still ciders, and described as sweet, spicy, fruity and floral were observed. Among these, it is worth mentioning 5 high-boiling point compounds found in an olfactometric zone where heavy, phenolic odours predominate in still ciders. The sensory descriptions obtained by Check-All-That-Apply classified the ice ciders mainly by their sweet taste and smoothness, these attributes being the most influential in the assessment of the overall quality of the ciders. The most highly valued ciders were described as the sweetest, most fruity ones, in agreement with their having the highest values for the ratio between total sugars and total acidity.


Asunto(s)
Bebidas Alcohólicas , Malus/química , Odorantes/análisis , Adulto , Bebidas Alcohólicas/análisis , Bebidas Alcohólicas/microbiología , Fraccionamiento Químico/métodos , Femenino , Análisis de los Alimentos/métodos , Jugos de Frutas y Vegetales , Humanos , Masculino , Persona de Mediana Edad , Olfatometría , Fenoles/análisis , Gusto , Compuestos Orgánicos Volátiles/análisis , Levaduras
13.
Food Chem ; 339: 127818, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32854038

RESUMEN

Native extracts from orange peels were obtained by a conventional method using acetone and, an alternative method using ionic liquid (1-butyl-3-methylimidazolium chloride ([C4mim]Cl)). The bioaccessibilities and cellular uptakes of carotenoids, esters and chlorophylls were evaluated, since the influence of esterification on bioaccessibility and bioavailability is not well established. For this, the extracts were emulsified, submitted to in vitro simulated digestion model according to the INFOGEST protocol, followed by uptake by Caco-2 cells. Compounds were separated, identified and quantified by HPLC-PDA-MS/MS. After digestion, 22.0% and 26.2% of the total carotenoids and 45.9% and 68.7% of the chlorophylls were bioaccessible from the acetone and [C4mim]Cl extracts, respectively. The bioaccessibilities of xanthophylls and carotenes were significantly higher than those of the mono- and diesters. The uptake by Caco-2 cells varied from 130.2 to 131.9 ng/mg cell protein for total carotenoids and from 243.8 to 234.2 ng/mg cell protein for chlorophylls in the acetone and [C4mim]Cl extracts, respectively. In general, xanthophylls and esters were better absorbed than carotenes.


Asunto(s)
Carotenoides/farmacocinética , Fraccionamiento Químico/métodos , Clorofila/farmacocinética , Citrus sinensis/química , Disponibilidad Biológica , Células CACO-2 , Carotenoides/análisis , Carotenoides/aislamiento & purificación , Clorofila/análisis , Clorofila/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Digestión , Ésteres/farmacocinética , Frutas/química , Humanos , Líquidos Iónicos/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacocinética , Espectrometría de Masas en Tándem , Xantófilas/análisis , Xantófilas/aislamiento & purificación , Xantófilas/farmacocinética
14.
Food Chem ; 339: 127862, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32860998

RESUMEN

In this study, pectinase-assisted extraction of cashew apple juice was modeled and optimized using a multi-layer artificial neural network (ANN) coupled with genetic algorithm (GA). The effect of incubation time, incubation temperature, and enzyme concentration on different responses such as yield, turbidity, ascorbic acid content, polyphenol content, total soluble solids, and pH was also determined. The developed ANN has minimum mean squared error values of 0.83, 40.92, 29.01, and 8.95 and maximum R values of 0.9999, 0.9972, 0.9995, and 0.9996 for training, testing, validation, and all data sets, respectively, which shows good agreement between the actual and predicted values. The optimum extraction parameters obtained using the developed ANN-GA were as follows: an incubation time of 64 min, incubation temperature of 32 °C, and enzyme concentration of 0.078%. The measured value of responses at the optimized process conditions were in accordance with the predicted values obtained using the developed ANN model.


Asunto(s)
Anacardium/química , Fraccionamiento Químico/métodos , Frío , Manipulación de Alimentos/métodos , Jugos de Frutas y Vegetales/análisis , Redes Neurales de la Computación , Poligalacturonasa/metabolismo
15.
Food Chem ; 338: 128101, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33091979

RESUMEN

Objective of this study was to recover bioactive compounds from grape pomace, and to investigate the effect of thermosonication in the rate of aqueous extraction. The best extraction for phenolics and total anthocyanins, was at 55 °C, amplitude of 40% and 6 min of treatment. The ultrasound assisted extraction showed superior results when compared to conventional extraction, extraction averages were: 11% total phenolic compounds, 25% total anthocyanins. The extract obtained by ultrasound showed higher antioxidant capacity when compared to the one obtained by conventional extraction. The alginate-Ca2+ capsules were stable when stored in the presence or absence of light, with a reduced t1/2 (absence of light), indicating longer half-life in the absence of light. The use of thermosonication favored greater amounts of bioactive compounds in the grape pomace aqueous extract, and this encapsulated extract in alginate-Ca2+ shows good stability and less degradation in the light absence.


Asunto(s)
Alginatos/química , Calcio/química , Fraccionamiento Químico/métodos , Fitoquímicos/química , Fitoquímicos/aislamiento & purificación , Ondas Ultrasónicas , Vitis/química , Cápsulas , Agua/química
16.
Food Chem ; 338: 128158, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33091981

RESUMEN

Tenebrio molitor larvae protein isolates (TPIs) were extracted using the alkaline extraction and acid precipitation methods (AEAP) assisted by NaCl (salting-in) and (NH4)2SO4 (salting-out) procedures. The structural, physicochemical, and functional properties of TPIs were investigated. It was found that the salt-assisted treatments did not affect the total amino acid content but altered specific amino acid compositions. The salting-in-AEAP extraction resulted in non-significant (P > 0.05) differences in zeta potential, hydrophobicity, thermal stability, solubility and foaming capacity compared with the AEAP extraction. Salting-out-AEAP extraction significantly (P < 0.05) increased overall protein solubility, emulsion activity, foaming capacity and stability that were associated with lower hydrophobicity, higher zeta potential, α-helix and disulfide bond contents. The salting-in-AEAP-out extraction generated the greatest protein yield (39.54%), emulsion activity index (55.5 m2/g), foaming capacity (205%) as well as foaming stability (65.59%).


Asunto(s)
Sulfato de Amonio/química , Fraccionamiento Químico/métodos , Proteínas de Insectos/química , Proteínas de Insectos/aislamiento & purificación , Larva/química , Cloruro de Sodio/química , Tenebrio/química , Aminoácidos/química , Animales , Fenómenos Químicos , Interacciones Hidrofóbicas e Hidrofílicas , Conformación Proteica en Hélice alfa , Solubilidad
17.
Food Chem ; 338: 128131, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33091982

RESUMEN

Soybean is one of the greatest crops in the world, with about 348.7 million tons being produced in 2018. Soybean hull is a by-product produced during the processing of soybean to obtain flour and oil. Though not being actually exploited, it is a source of polyphenols with antioxidant activity. Here, the extraction of polyphenols from soybean hull was performed by means of an alkaline hydrolysis treatment, which was optimized by the response surface methodology. At the optimal region, a total phenolic content of 0.72 g gallic acid equivalents per 100 g of soybean hull was obtained with an antioxidant activity of 2.17 mmoles of Trolox equivalents. Polyphenols responsible for the antioxidant activities were identified by LC-MS, including phenolic acids, anthocyanins, stilbenes, and the two main isoflavones of soybean, daidzein and genistein, in their non-glycosylated form. Other alternative extraction methods based on Aspergillus oryzae fermentation and α-amylase hydrolysis are also proposed.


Asunto(s)
Antioxidantes/aislamiento & purificación , Fraccionamiento Químico/métodos , Tecnología Química Verde/métodos , Polifenoles/aislamiento & purificación , Soja/química , Antioxidantes/química , Aspergillus oryzae/metabolismo , Fermentación , Hidrólisis , Polifenoles/química , alfa-Amilasas/metabolismo
18.
Food Chem ; 338: 128144, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33092004

RESUMEN

A weak ion-exchange membrane (P-COOH) was synthesized by alkaline hydrolysis of a polyacrylonitrile nanofiber membrane prepared by electrospinning process. The P-COOH membrane was characterized for its physical properties and its application for purification of lysozyme from chicken egg white was investigated. The lysozyme adsorption efficiency of the P-COOH membrane operating in a stirred cell contactor (Millipore, Model 8010) was evaluated. The effects of key parameters such as the feed concentration, the rotating speed, the flow rate of feed and the operating pressure were studied. The results showed successful purification of lysozyme with a high recovery yield of 98% and a purification factor of 63 in a single step. The purification strategy was scaled-up to the higher feedstock loading volume of 32.7 and 70 mL using stirred cell contactors of Model 8050 and 8200, respectively. The scale-up processes achieved similar purification results, proving linear scalability of the purification technique adopted.


Asunto(s)
Fraccionamiento Químico/instrumentación , Clara de Huevo , Membranas Artificiales , Muramidasa/aislamiento & purificación , Nanofibras/química , Resinas Acrílicas/química , Adsorción , Animales , Intercambio Iónico , Muramidasa/química
19.
Food Chem ; 339: 128086, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33152877

RESUMEN

Sweet cherries processing produces big amounts of wastes mainly constituted by cherry pomace that can be a source of bioactive polyphenols. However, during the extraction process, an important fraction called non-extractable polyphenols (NEPs) remains retained in the extraction residue. This work describes the development of an enzyme-assisted extraction (EAE) method to obtain NEPs from sweet cherry pomace employing three different enzymes. Box-Behnken experimental designs were employed to select the optimal conditions of extraction time, temperature, enzyme concentration, and pH. The total phenolic and proanthocyanidin contents and the antioxidant and antihypertensive capacities were measured. Optimal EAE conditions extracted higher content of proanthocyanidins and with higher bioactivity from extraction residue than alkaline and acid hydrolysis. Moreover, there were higher amounts of bioactive phenolics in the extraction residue than in the sweet cherry pomace extract. The estimation of NEPs molecular weight distribution by HPLC-SEC demonstrated that EAE extracted NEPs with high molecular weight.


Asunto(s)
Fraccionamiento Químico/métodos , Enzimas/metabolismo , Polifenoles/aislamiento & purificación , Prunus avium/química , Frutas/química , Concentración de Iones de Hidrógeno , Temperatura , Factores de Tiempo
20.
Talanta ; 224: 121862, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33379073

RESUMEN

Since coronavirus disease 2019 (COVID-19) started as a fast-spreading pandemic, causing a huge number of deaths worldwide, several therapeutic options have been tested to counteract or reduce the clinical symptoms of patients infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Currently, no specific drugs for COVID-19 are available, but many antiviral agents have been authorised by several national agencies. Most of them are under investigation in both preclinical and clinical trials; however, pharmacokinetic and metabolism studies are needed to identify the most suitable dose to achieve the desired effect on SARS-CoV-2. Therefore, the efforts of the scientific community have focused on the screening of therapies able to counteract the most severe effects of the infection, as well as on the search of sensitive and selective analytical methods for drug detection in biological matrices, both fluids and tissues. In the last decade, many analytical methods have been proposed for the detection and quantification of antiviral compounds currently being tested for COVID-19 treatment. In this review, a critical discussion on the overall analytical procedure is provided, i.e (a) sample pre-treatment and extraction methods such as protein precipitation (PP), solid-phase extraction (SPE), liquid-liquid extraction (LLE), ultrasound-assisted extraction (UAE) and QuEChERS (quick, easy, cheap, effective, rugged and safe), (b) detection and quantification methods such as potentiometry, spectrofluorimetry and mass spectrometry (MS) as well as (c) methods including a preliminary separation step, such as high performance liquid chromatography (HPLC) and capillary electrophoresis (CE) coupled to UV-Vis or MS detection. Further current trends, advantages and disadvantages and prospects of these methods have been discussed, to help the analytical advances in reducing the harm caused by the SARS-CoV-2 virus.


Asunto(s)
Antivirales/análisis , Animales , Antivirales/química , Antivirales/aislamiento & purificación , /epidemiología , Fraccionamiento Químico , Cromatografía Líquida de Alta Presión , Humanos , Pandemias , Espectrometría de Masas en Tándem
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