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1.
Int J Biol Macromol ; 254(Pt 2): 127974, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37949273

RESUMEN

A new and green development in the field of food packaging is the use of colorimetric films containing anthocyanins, which not only can respond to food spoilage but also have no environmental risk and help the environment full of unacceptable and polluted substances created by humans. In this research, a completely natural film (GCNG) was made using natural materials including tragacanth gummifer (G), chitosan nanoparticles (C), and an extract containing anthocyanins of a type of wild grape called Sardasht black (G) with Alumina nanoparticles (N) for use in food packaging. This biodegradable film (GCNG) presented relatively wide color differences from red to blue in different buffer solutions (pH 2-12), which was clearly observed by the naked eye. Sardasht black grape extract contains large amounts of anthocyanins and antioxidants that can be extracted and used in the preparation of packaging films. The properties of prepared films, including mechanical properties, permeability to water vapor, solubility, swelling, as well as antimicrobial properties were checked by measuring the diameter of the diffusion area by agar disk test. GCNG films showed strong antioxidant activity and good antibacterial activity against E. coli and S. aureus. The results suggested this film has promising potential as an active and smart packaging material for applications in the food industry.


Asunto(s)
Quitosano , Nanopartículas , Vitis , Humanos , Quitosano/química , Embalaje de Alimentos/métodos , Antocianinas/farmacología , Antocianinas/química , Vitis/química , Astragalus gummifer , Escherichia coli , Staphylococcus aureus , Antioxidantes/farmacología , Antioxidantes/química , Antibacterianos/farmacología , Antibacterianos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Nanopartículas/química
2.
Mikrochim Acta ; 186(10): 678, 2019 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-31515633

RESUMEN

Nanosheets of a porous layered double hydroxide were directionally arranged on boehmite nanowires and porous carbon and used as a coating for solid-phase microextraction (SPME) method. Porous carbon tubes were prepared from goat grass and then coated with layered double hydroxide nanosheets and boehmite nanowires. The nanomaterial was placed on a stainless-steel wire which then was used for the extraction of fifteen agrochemicals from aqueous sample solutions. The extraction temperature, extraction time, ionic strength, stirring rate, and desorption temperature and time were optimized. Following thermal desorption of the agrochemicals in the injector of the gas chromatograph, they were quantified by GC/MS. Under optimum conditions, the repeatability for one fiber, expressed as relative standard deviation, was between 2.9 and 11.1%. The detection limits for the agrochemicals are between 2-29 ng L-1. The method is simple, fast, and inexpensive (in terms of equipment). The fiber is thermally stable, and the relative recoveries from spiked samples are better compared to conventional methods of extraction. Graphical abstract Schematic illustration of the preparation of three-dimensional hierarchical boehmite/ layered double hydroxides/ porous carbon (Boeh/LDH/pC) SPME fibers and application for the extraction of fifteen agrochemicals from aqueous sample solutions following quantification by GC/MS.


Asunto(s)
Agroquímicos/química , Nanocompuestos/química , Plaguicidas/análisis , Extractos Vegetales/análisis , Microextracción en Fase Sólida/instrumentación , Contaminantes Químicos del Agua/química , Hidróxido de Aluminio/química , Óxido de Aluminio/química , Carbono/química , Hidróxidos/química , Poaceae/química , Acero Inoxidable/química
3.
Nat Prod Res ; 32(2): 243-245, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28659062

RESUMEN

Zn/Al layered double hydroxide (LDH) films were fabricated in situ with anodic aluminium oxide aluminium as both the substrate and the sole aluminium source by means of urea hydrolysis. Headspace solid phase microextraction using LDH fibre in combination with capillary GC-MS was utilised as a monitoring technique for the collection and detection of the volatile compounds of Origanum vulgare. Experimental parameters, including the sample weight, microwave power, extraction time and humidity effect, were examined and optimised.


Asunto(s)
Aceites Volátiles/análisis , Origanum/química , Microextracción en Fase Sólida/instrumentación , Microextracción en Fase Sólida/métodos , Aluminio/química , Óxido de Aluminio/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Hidrólisis , Microondas , Nanoporos , Urea/química
4.
Nat Prod Res ; 30(8): 991-4, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26329700

RESUMEN

This article investigates the effect of microwaves on the amount of volatile compounds Achillea tenuifolia Lam with two methods, headspace single-drop microextraction and microwave-assisted headspace single-drop microextraction (MA-SDME), for the analysis of essential oil. Solvent selection, solvent volume, microwave power, irradiation time and sample mass were optimised by the simplex method.


Asunto(s)
Achillea/química , Aceites Volátiles/análisis , Aceites de Plantas/análisis , Destilación , Cromatografía de Gases y Espectrometría de Masas , Microondas , Solventes
5.
Nat Prod Res ; 29(19): 1789-92, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25613724

RESUMEN

In this work, a highly porous fibre coated with polythiophene/hexagonally ordered silica nanocomposite (PT/SBA-15) was prepared and used for extraction of essential oils with microwave-assisted distillation headspace solid phase microextraction (MA-HS-SPME) method. The prepared nanomaterials were immobilised on a stainless steel wire for fabrication of the SPME fibre. Using MA-HS-SPME followed by GC-MS, 24 compounds were separated and identified in Achillea tenuifolia, which mainly included limonene (28.6%), α-cadinol (12.7%), borneol (6.7%), caryophyllene oxide (3.2%), bornyl acetate (4.3%), camphene (3.2%) and para-cymene (2.3%). The experimental results showed that the polythiophene/hexagonally ordered silica nanocomposite fibres were suitable for the semi-quantitative study of the composition of essential oils in plant materials and for monitoring the variations in the volatile components of the plants.


Asunto(s)
Achillea/química , Nanocompuestos , Aceites Volátiles/análisis , Aceites de Plantas/análisis , Microextracción en Fase Sólida/métodos , Polímeros , Dióxido de Silicio , Tiofenos
6.
Nat Prod Res ; 29(9): 833-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25496469

RESUMEN

In this paper, for the first time, an inorganic-organic hybrid material based on ZnO nanoparticles was anchored to a composite made from polythiophene and hexagonally ordered silica (ZnO/PT/SBA-15) for use in solid-phase fibre microextraction (SPME) of medicinal plants. A homemade SPME apparatus was used for the extraction of volatile components of Ziziphora tenuior L. A simplex method was used for optimisation of five different parameters affecting the efficiency of the extraction. The main constituents extracted by ZnO/PT/SBA-15 and PDMS fibres and hydrodistillation (HD) methods, respectively, included pulegone (51.25%, 53.64% and 56.68%), limonene (6.73%, 6.58% and 8.3%), caryophyllene oxide (5.33%, 4.31% and 4.53%) and 1,8-cineole (4.21%, 3.31% and 3.18%). In comparison with the HD method, the proposed technique could equally monitor almost all the components of the sample, in an easier way, in a shorter time and requiring a much lower amount of the sample.


Asunto(s)
Lamiaceae/química , Aceites Volátiles/análisis , Aceites de Plantas/análisis , Microextracción en Fase Sólida/métodos , Compuestos Orgánicos Volátiles/análisis , Monoterpenos Ciclohexánicos , Ciclohexanoles/química , Ciclohexanoles/aislamiento & purificación , Ciclohexenos/química , Ciclohexenos/aislamiento & purificación , Eucaliptol , Limoneno , Monoterpenos/química , Monoterpenos/aislamiento & purificación , Nanopartículas/química , Plantas Medicinales/química , Sesquiterpenos Policíclicos , Polímeros/química , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Dióxido de Silicio/química , Microextracción en Fase Sólida/instrumentación , Terpenos/química , Terpenos/aislamiento & purificación , Tiofenos/química , Óxido de Zinc/química
7.
Chin J Nat Med ; 12(7): 505-11, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25053549

RESUMEN

Flavonoids, anthocyanins, antioxidant capability, total phenolic, ascorbic acid contents, and essential oils compounds of Ziziphora tenuoir (Lamiaceae) for polar and non-polar subfraction in different stages of growth (pre-flowering and flowering) were evaluated in this work. Antioxidant activities of the samples were determined by three testing systems namely DPPH, ß-carotene/linoleic acid, and reducing power assay. In the DPPH system, the highest radical scavenging activity was seen by the nonpolar subfraction of the methanol extract in the flowering stage (IC50 43.17 ± 3.68 µg·mL(-1)). Large differences in the amount of phenolic compounds, antioxidant activity, anthocyanins, and flavonoids of Z. tenuoir in two stages of growth were detected. The chemical composition of the hydrodistilled essential oil of the aerial parts of Z. tenuoir was analyzed by GC/MS and compared in the two stages of growth. The main constituents of the 28 identified compounds in the oil were found to be pulegone (67.34% vs 59.61%), ß-humulene (3.24% vs 3.25%), and limonene (5.06% vs 2.57%) at the flowering and pre-flowering stages, respectively.


Asunto(s)
Antioxidantes/química , Lamiaceae/química , Lamiaceae/crecimiento & desarrollo , Aceites Volátiles/química , Extractos Vegetales/química , Antioxidantes/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Estructura Molecular , Aceites Volátiles/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación
8.
J Sep Sci ; 36(5): 872-7, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23483734

RESUMEN

Nanoporous silica was prepared and functionalized with amino propyl-triethoxysilane to be used as a highly porous fiber-coating material for solid-phase microextraction (SPME). The prepared nanomaterials were immobilized onto a stainless steel wire for fabrication of the SPME fiber. The proposed fiber was evaluated for the extraction of volatile component of Citrus aurantium L. leaves. A homemade microwave-assisted extraction followed by headspace (HS) solid-phase apparatus was used for the extraction of volatile components. For optimization of factors affecting the extraction efficiency of the volatile compounds, a simplex optimization method was used. The repeatability for one fiber (n = 4), expressed as RSD, was between 3.1 and 8.6% and the reproducibility for five prepared fibers was between 10.1 and 14.9% for the test compounds. Using microwave-assisted distillation HS-SPME followed by GC-MS, 53 compounds were separated and identified in C. aurantium L., which mainly included limonene (62.0%), linalool (7.47%), trans-ß-Ocimene (3.47%), and caryophyllene (2.05%). In comparison to a hydrodistillation method, the proposed technique could equally monitor almost all the components of the sample, in an easier way, which was rapid and required a much lower amount of sample.


Asunto(s)
Nanofibras/química , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificación , Microextracción en Fase Sólida/métodos , Adsorción , Cromatografía de Gases y Espectrometría de Masas , Microondas , Microextracción en Fase Sólida/instrumentación
9.
Food Chem ; 138(1): 251-5, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23265484

RESUMEN

To avoid the traditional and time consuming hydrodistillation, the analyses of volatile components in aerial parts of Echinophora platyloba DC was carried out by a simple microwave distillation followed by headspace single drop microextraction (MD-HS-SDME) coupled to gas chromatography-mass spectrometry (GC-MS). The headspace volatile compounds were collected after irradiation using a single drop of n-heptadecan. The extraction conditions were optimised using the relative peak areas as index. The chemical composition of the MD-HS-SDME extracts was confirmed according to their retention indexes and mass spectra. Fifty-three components were extracted and identified by using the MD-HS-SDME method. E-ß-ocimene (53.81%), R-D-decalactone (12.75%), α-pinene (6.43%), n-heptanol (6.27%), ß-phellanderne (2.70%) and linalool (1.89%) were the major constituents.


Asunto(s)
Apiaceae/química , Destilación/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Microextracción en Fase Sólida/métodos , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/aislamiento & purificación , Destilación/instrumentación , Microondas
10.
Nat Prod Res ; 27(13): 1228-31, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22946505

RESUMEN

This article investigates the effect of microwaves on the amount of volatile compounds from Thymus kotschyanus Boiss with four methods, headspace single-drop microextraction, microwave-assisted headspace single-drop microextraction, microwave distillation extraction and hydrodistillation, for the analysis of essential oil. Solvent selection, solvent volume, microwave power, irradiation time and sample mass were optimised by simplex method.


Asunto(s)
Microondas , Monoterpenos/química , Aceites Volátiles/química , Aceites de Plantas/química , Sesquiterpenos/química , Thymus (Planta)/química , Compuestos Orgánicos Volátiles/química , Destilación , Microextracción en Fase Líquida
11.
Phytochem Anal ; 24(1): 69-74, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22767454

RESUMEN

INTRODUCTION: The development of simple, rapid and solvent-free methods for the analysis of essential oils is highly desirable. Microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) is a new sampling and concentration technique for the extraction of volatile components in medicinal plants. The main advantages of this method are the reduction of extraction time and of organic solvent. OBJECTIVE: A highly porous Santa Barbara amorphous (SBA-15)/polyaniline material was prepared in order to produce a SPME fibre. The proposed fibre was evaluated for the extraction of the volatile component of Teucrium polium L. METHODOLOGY: A homemade MA-HS-SPME apparatus was used for the extraction of volatile components. Highly porous SBA-15/polyaniline materials were prepared for SPME. The prepared nanomaterial was immobilized onto a stainless steel wire for fabrication of the SPME fibre. RESULTS: The SBA-15/polyaniline nanonporous fibre could adsorb volatile components of T. polium efficiently. In comparison with a HD method, the proposed technique could equally monitor almost all the components of the sample, but in an easier way that was rapid and required a much lower amount of sample. CONCLUSION: The experimental results showed that the nanoporous fibre was suitable for the semi-quantitative study of the composition of essential oils in plant materials and monitoring the variations in the volatile components of the plants.


Asunto(s)
Aceites Volátiles/análisis , Microextracción en Fase Sólida/métodos , Teucrium/química , Compuestos Orgánicos Volátiles/análisis , Compuestos de Anilina/química , Microondas , Dióxido de Silicio/química , Microextracción en Fase Sólida/instrumentación , Agua/química
12.
Anal Chim Acta ; 701(1): 1-5, 2011 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-21763801

RESUMEN

Headspace solid phase microextraction using anodized aluminum fiber in combination with capillary GC-MS was utilized as monitoring technique for the collection and detection of the volatile compounds of Echinophora platyloba DC. Experimental parameters, including the sample weight, extraction temperature, extraction time and humidity effect, desorption time and desorption temperature were examined and optimized. Using HS-SPME followed by GC-MS, 53 compounds were separated and identified in E. platyloba DC, which mainly included E-ß ocimene (47.63%), R-D-decalactone (13.28%), α-pinene (7.43%) and nonane (6.71%). Compared with hydrodistillation (HD), HS-SPME, provides the advantages of a small amount of sample, timesaving, simplicity and cheapness. To the best of our knowledge, this is the first report on using anodized aluminum fiber in solid-phase microextraction coupled to headspace for the investigation of volatile fraction of medicinal plant.


Asunto(s)
Aluminio/química , Aceites Volátiles/aislamiento & purificación , Extractos Vegetales/química , Plantas Medicinales/química , Microextracción en Fase Sólida/instrumentación , Compuestos Orgánicos Volátiles/aislamiento & purificación , Electrodos , Diseño de Equipo , Cromatografía de Gases y Espectrometría de Masas/economía , Cromatografía de Gases y Espectrometría de Masas/métodos , Humedad , Microextracción en Fase Sólida/economía , Microextracción en Fase Sólida/métodos
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