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1.
Food Chem ; 406: 135054, 2023 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-36450196

RESUMEN

Bioactive functional coatings constitute a trendy topic due to they reduce postharvest fruit losses worldwide. Also, they could be carriers of biocompounds providing health benefits to the consumer. In this work, an innovative natural bioactive coating based on Natural Deep Eutectic Solvents (NADES) and Larrea divaricata extract was optimized by mixture-mixture design for the management of postharvest diseases caused by Monilinia fructicola. A NADES composed of lactic acid-glucose-water (LGH) for phenolic extraction from L. divaricata was optimized by a Simplex Lattice design and response surface methodology (RSM).Then, a d-optimal mixture-mixture design was carried out in order to optimize the bioactive coating composition, being the optimal proportion of 0.7 L. divaricata-LGH extract and 0.3 NADES plasticizer (composed by glycerol, citric acid and water). The optimal biocoating achieved an in vitro antimicrobial activity of 72 % against M. fructicola. Interestingly, NADES plasticizer improves the biocoating functionality, creating a smooth and uniform surface.


Asunto(s)
Disolventes Eutécticos Profundos , Extractos Vegetales , Solventes , Extractos Vegetales/farmacología , Plastificantes , Agua
2.
Biol Trace Elem Res ; 201(9): 4590-4599, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36550265

RESUMEN

In this work, microwave-induced plasma optical emission spectrometry was applied for multielement determination in South American wine samples. The analytes were determined after acid digestion of 47 samples of Brazilian and Argentinian wines. Then, logistic regression, support vector machine, and decision tree for exploratory analysis and comparison of these algorithms in differentiating red wine samples by region of origin were carried out. All wine samples were classified according to their geographical origin. The quantification limits (mg L-1) were P: 0.06, B: 0.08, K: 0.17, Mn: 0.002, Cr: 0.002, and Al: 0.02. The accuracy of the method was evaluated by analyzing the wine samples by ICP OES for results' comparison. The concentrations in mg L-1 found for each element in wine samples were as follows: Al (< 0.02-1.82), Cr (0.15-0.50), Mn (< 0.002-0.8), P (97-277), B (1.7-11.6), Pb (< 0.06-0.3), Na (8.84-41.57), and K (604-1701), in mg L-1.


Asunto(s)
Oligoelementos , Vino , Vino/análisis , Espectrometría de Masas/métodos , Inteligencia Artificial , Análisis Espectral/métodos , Brasil , Oligoelementos/análisis
3.
Anal Chim Acta ; 1179: 338831, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34535267

RESUMEN

Natural Deep Eutectic Solvents (NADES) are highly important for Green Chemistry principles and can be used instead of harmful organic solvents. Indeed, nowadays smartphone-based analytical devices can replace some traditional laboratory equipment. In the present work, a smartphone based dual spectrophotometer and spectrofluorometer device was designed, 3D manufactured, and validated. A resolution of 0.241 ± 0.010 pixel.nm-1 and a stability comparable with commercial instruments were obtained. Using the proposed device it was possible, for the first time, to study the role of water in NADES (fructose:urea:water) preparation, by testing the influence of structural and dilution water. In this sense, it was observed that when water was added before NADES preparation (integrated into the superstructure of the solvent), fluorescence and absorbance intensities sharply decayed (up to 90% and 95%, respectively). In contrast, dilution water had minor effects on spectroscopic features of the eutectic system, which was expressed as 29% and 23% of diminution of signal intensities for both techniques. The obtained results suggest that the moment the water is added plays a significant role in NADES properties.


Asunto(s)
Teléfono Inteligente , Agua , Extractos Vegetales , Solventes , Análisis Espectral
4.
Methods Mol Biol ; 1906: 197-206, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30488394

RESUMEN

Microchip electrophoresis (ME) results from miniaturization of capillary electrophoresis (CE) to a microfabricated separation device. Both techniques have common characteristics, but in some aspects, the microfluidic separation device has unique features resulting from its planar miniaturized format. Here we describe the process to transfer of CE to ME and the benefits and drawbacks of the chip with respect to the capillary. A practical guide for method development on the microchip for small ionizable molecules such as phenolic compounds, amino acids, or alkaloids is also presented.


Asunto(s)
Electroforesis por Microchip/instrumentación , Bibliotecas de Moléculas Pequeñas/análisis , Alcaloides/análisis , Aminoácidos/análisis , Diseño de Equipo , Técnicas Analíticas Microfluídicas/instrumentación , Fenoles/análisis
5.
Anal Chim Acta ; 1038: 1-10, 2018 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-30278889

RESUMEN

The concept of sustainable development has impacted in analytical chemistry changing the way of thinking processes and methods. It is important for analytical chemists to consider how sample preparation can integrate the basic concepts of Green Chemistry. In this sense, the replacement of traditional organic solvents is of utmost importance. Natural Deep Eutectic Solvents (NADES) have come to light as a green alternative. In the last few years, a growing number of contributions have applied these natural solvents proving their efficiency in terms of extraction ability, analyte stabilization capacity and detection compatibility. However, the arising question that has to be answered is: the use of NADES is enough to green an extraction process? This review presents an overview of knowledge regarding sustainability of NADES-based extraction procedures, focused on reported literature within the timeframe spanning from 2011 up to date. The contributions were analyzed from a green perspective in terms of energy, time, sample and solvent consumption. Moreover, we include a critical analysis to clarify whether the use of NADES as extraction media is enough for greening an analytical methodology; strategies to make them even greener are also presented. Finally, recent trends and future perspectives on how NADES-based extraction approaches in combination with computational methodologies can contribute are discussed.

6.
Electrophoresis ; 39(13): 1621-1627, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29572874

RESUMEN

Rising interest in ellagic acid (EA) present in functional foods is supported by its antimutagenic, anticarcinogenic, antiviral, antibacterial and antioxidative effects. The present approach presents for the first time the determination of ellagic acid and other phenolics in wines by miniaturized solid phase extraction prior to capillary zone electrophoresis (CZE) with UV. The extraction was performed using a home-made miniaturized pipette tip column. The procedure allowed a significant reduction in conditioning/sample/washing/elution volumes. The effects of important factors affecting the extraction efficiency as well as electrophoretic performance were investigated to acquire optimum conditions. The analytes were separated within 10 min with a BGE containing 30 mmol/L sodium tetraborate 10% v/v MeOH pH 9.10. The optimized method was applied to the determination of ellagic acid in commercial and pilot-scale wines. Indeed, the content of EA was correlated with viticultural parameters such as grape varietal, production area, and aging conditions (oak wood guard and glass bottle ward). In order to validate the results, a comparison between the CZE and HPLC data was made.


Asunto(s)
Electroforesis Capilar , Ácido Elágico/análisis , Vino/análisis , Cromatografía Líquida de Alta Presión , Electroforesis Capilar/métodos , Análisis de los Alimentos , Calidad de los Alimentos , Vitis/química , Madera
7.
Food Chem ; 239: 671-678, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-28873620

RESUMEN

An environmentally friendly method for the phenolic compound extraction from agro-food industrial by-products was developed in order to contribute with their sustainable valorization. A Natural Deep Eutectic Solvent was chemometrically-designed for the first time and compared with traditional solvents in terms of analyte stabilization. The combination of lactic acid, glucose and 15% water (LGH-15) was selected as optimal. A high-efficiency ultrasound-assisted extraction mediated by LGH-15 prior to HPLC-DAD allows the determination of 14 phenols in onion, olive, tomato and pear industrial by-products. NADES synthesis as well as the extraction procedures were optimized by Response Surface Methodology. Thus, phenolic determination in these complex samples was achieved by a simple, non-expensive, eco-friendly and robust system. The application to different matrices demonstrated the versatility of the proposed method. NADES opens interesting perspectives for their potential use as vehicles of bioactive compounds as food additives or pharmaceuticals.


Asunto(s)
Industria de Alimentos , Cromatografía Líquida de Alta Presión , Fenoles , Extractos Vegetales , Solventes , Agua
8.
Electrophoresis ; 38(21): 2704-2711, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28881013

RESUMEN

A novel methodology is presented for the enhanced electrochemical detection of oleuropein in complex plant matrices by Graphene Oxide Pencil Grahite Electrode (GOPGE) in combination with a buffer modified with a Natural Deep Eutectic Solvent, containing 10% (v/v) of Lactic acid, Glucose and H2 O (LGH). The electrochemical behavior of oleuropein in the modified-working buffer was examined using differential pulse voltammetry. The combination of both modifications, NADES modified buffer and nanomaterial modified electrode, LGH-GOPGE, resulted on a signal enhancement of 5.3 times higher than the bare electrode with unmodified buffer. A calibration curve of oleuropein was performed between 0.10 to 37 µM and a good linearity was obtained with a correlation coefficient of 0.989. Detection and quantification limits of the method were obtained as 30 and 102 nM, respectively. In addition, precision studies indicated that the voltammetric method was sufficiently repeatable, %RSD 0.01 and 3.16 (n = 5) for potential and intensity, respectively. Finally, the proposed electrochemical sensor was successfully applied to the determination of oleuropein in an olive leaf extract prepared by ultrasound-assisted extraction. The results obtained with the proposed electrochemical sensor were compared with Capillary Zone Electrophoresis analysis with satisfactory results.


Asunto(s)
Técnicas Electroquímicas/métodos , Grafito/química , Iridoides/análisis , Óxidos/química , Solventes/química , Técnicas Biosensibles/métodos , Electrodos , Electroforesis Capilar/métodos , Glucósidos Iridoides , Iridoides/aislamiento & purificación , Límite de Detección , Olea/química , Extractos Vegetales/química , Hojas de la Planta/química
9.
Anal Bioanal Chem ; 408(30): 8643-8653, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27526092

RESUMEN

The present critical review provides a summary of representative articles describing the analysis of wine by microchip electrophoresis. Special emphasis has been given to those compounds able to provide background information to achieve the differentiation of wines according to botanical origin, provenance, vintage and quality or assure wine authentication. This review focuses on capillary electrophoresis (CE) microchips dedicated to the analysis of wine covering all the contributions concerning this area. The most relevant compounds in wine analysis such as phenols, organic acids, inorganic species, aldehydes, sugars, alcohols, and neuroactive amines were considered. Moreover, a special section is dedicated to the potential of CE microchip for wine classification. Indeed, potential directions for the future are discussed.


Asunto(s)
Electroforesis Capilar/métodos , Electroforesis por Microchip/métodos , Vitis/química , Vino/análisis , Alcoholes/análisis , Aldehídos/análisis , Aminas Biogénicas/análisis , Ácidos Carboxílicos/análisis , Electroforesis Capilar/instrumentación , Electroforesis por Microchip/instrumentación , Fermentación , Humanos , Fenoles/análisis , Azúcares/análisis
10.
Environ Sci Technol ; 47(12): 6606-13, 2013 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-23679130

RESUMEN

Concerns regard watering crops with Hg contaminated waters have arisen worldwide recently. In these sense Hg uptake by Vitis vinifera L. cv. Malbec was evaluated under greenhouse conditions by the administration of Hg(2+) for 4 days through irrigation water (short-term administration). Vines uptake Hg translocating it from roots through stems to leaves. Roots accumulated the higher Hg concentration. Hg in stems and leaves was accumulated mostly as organic Hg, bind to different moieties. Size exclusion chromatography (SEC) and ion pair chromatography (IPC) were employed to reach insights into these ligands. Hg is distributed mainly in high molecular weight fractions of 669 kDa in vine plants. In stems and leaves, Hg-S associations were found in 669 and 66 kDa fractions. Hg-S association at 66 kDa suggests a possible protein or peptide binding affecting vines normal physiology. Since Hg contamination through organomercurials is more harmful than Hg(2+) itself, methyl mercury, dimethyl mercury, and phenyl mercury, more toxic Hg species were evaluated with negative results.


Asunto(s)
Riego Agrícola , Mercurio/análisis , Medición de Riesgo/métodos , Vitis/metabolismo , Cromatografía en Gel , Mercurio/toxicidad , Vitis/efectos de los fármacos
11.
Electrophoresis ; 33(15): 2240-52, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22887148

RESUMEN

The accurate determination of marker chemical species in grape, musts, and wines presents a unique analytical challenge with high impact on diverse areas of knowledge such as health, plant physiology, and economy. Capillary electromigration techniques have emerged as a powerful tool, allowing the separation and identification of highly polar compounds that cannot be easily separated by traditional HPLC methods, providing complementary information and permitting the simultaneous analysis of analytes with different nature in a single run. The main advantage of CE over traditional methods for wine analysis is that in most cases samples require no treatment other than filtration. The purpose of this article is to present a revision on capillary electromigration methods applied to the analysis of wine and its precursors over the last decade. The current state of the art of the topic is evaluated, with special emphasis on the natural compounds that have allowed wine to be considered as a functional food. The most representative revised compounds are phenolic compounds, amino acids, proteins, elemental species, mycotoxins, and organic acids. Finally, a discussion on future trends of the role of capillary electrophoresis in the field of analytical characterization of wines for routine analysis, wine classification, as well as multidisciplinary aspects of the so-called "from soil to glass" chain is presented.


Asunto(s)
Electroforesis Capilar/métodos , Vitis/química , Vino/análisis , Aminoácidos/análisis , Micotoxinas/análisis , Fenoles/análisis
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