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1.
Mar Drugs ; 21(8)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37623717

RESUMEN

Carpobrotus edulis (L.) N.E.Br. (Hottentot-fig) is a problematic invasive species found in coastal areas worldwide. Mechanical removal is a common control method, leaving the removed biomass available as a possible source of natural phytochemicals with prospective commercial applications. While the Hottentot-fig's vegetative organs have been studied previously, this work establishes for the first time a seasonal and spatial comparative analysis of its nutritional, chemical, and bioactivity profiles (in three locations over four seasons). Proximate and mineral contents were assessed, along with its phenolic composition and in vitro antioxidant and anti-inflammatory properties. Hottentot-fig's biomass offered a good supply of nutrients, mainly carbohydrates, proteins, and minerals, with a tendency for higher concentrations of the most relevant minerals and proteins in autumn and winter, and in plants from sites A (Ria de Alvor lagoon) and B (Ancão beach). The extracts were rich in polyphenolics, with higher levels in spring and summer, especially for luteolin-7-O-glucoside and salicylic and coumaric acids. The extracts were also effective antioxidants, with stronger radical scavenging activities in spring and summer, along with anti-inflammatory properties. Our results suggest that the usually discarded plant material of this invasive halophyte could be valuable as a source of natural products with potential biotechnological applications in the food and nutraceutical industries.


Asunto(s)
Antioxidantes , Suplementos Dietéticos , Estudios Prospectivos , Estaciones del Año , Antioxidantes/farmacología , Extractos Vegetales
2.
Molecules ; 28(3)2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36770845

RESUMEN

In this work, a new analytical approach is proposed for monitoring biogenic volatile organic compounds (BVOCs) by combining headspace bar adsorptive microextraction (HS-BAµE) with gas chromatography-mass spectrometry (GC-MS). The HS-BAµE methodology was developed, optimized, validated and applied for the analysis of BVOCs emitted from two tree species (Eucalyptus globulus Labill. and Pinus pinaster Aiton) and compared with headspace solid phase microextraction (HS-SPME), commonly accepted as a reference technique. To achieve optimum experimental conditions, numerous assays were carried out by both methodologies, studying the release of the five major monoterpenoids (α-pinene, ß-pinene, myrcene, limonene and 1,8-cineole) from the leaves of the tree species, whereas the maximum selectivity and efficiency were obtained using an activated carbon and PDMS/DVB fiber as sorbent phases for HS-BAµE and HS-SPME, respectively. Under optimized experimental conditions, both methodologies showed similar profiling and proportional responses, although the latter present a higher sensitivity in the analytical configuration used. For the five monoterpenoids studied, acceptable detection limits (LODs = 5.0 µg L-1) and suitable linear dynamic ranges (20.0-100.0 mg L-1; r2 ≥ 0.9959) were achieved, and intra- and inter-day studies proved that both methodologies exhibited good results (RSD and %RE ≤ 19.9%), which indicates a good fit for the assessment of BVOCs by the HS-BAµE/GC-MS methodology. Assays performed on sampled leaves by both optimized and validated methodologies showed high levels of the five major BVOCs released from E. globulus Labill. (10.2 ± 1.3 to 7828.0 ± 40.0 µg g-1) and P. pinaster Aiton (9.2 ± 1.4 to 3503.8 ± 396.3 µg g-1), which might act as potential fuel during forest fire's propagation, particularly under extreme atmospheric conditions. This is the first time that BAµE technology was applied in the HS sampling mode, and, in addition to other advantages, it has proven to be an effective and promising analytical alternative for monitoring VOCs, given its great simplicity, easy handling and low cost.


Asunto(s)
Árboles , Compuestos Orgánicos Volátiles , Adsorción , Microextracción en Fase Sólida/métodos , Cromatografía de Gases y Espectrometría de Masas , Eucaliptol
3.
Molecules ; 26(8)2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33918766

RESUMEN

The analysis of controlled drugs in forensic matrices, i.e., urine, blood, plasma, saliva, and hair, is one of the current hot topics in the clinical and toxicological context. The use of microextraction-based approaches has gained considerable notoriety, mainly due to the great simplicity, cost-benefit, and environmental sustainability. For this reason, the application of these innovative techniques has become more relevant than ever in programs for monitoring priority substances such as the main illicit drugs, e.g., opioids, stimulants, cannabinoids, hallucinogens, dissociative drugs, and related compounds. The present contribution aims to make a comprehensive review on the state-of-the art advantages and future trends on the application of microextraction-based techniques for screening-controlled drugs in the forensic context.


Asunto(s)
Medicina Legal , Microextracción en Fase Líquida/métodos , Preparaciones Farmacéuticas/análisis , Microextracción en Fase Sólida/métodos , Humanos , Drogas Ilícitas/análisis
4.
Molecules ; 26(11)2021 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-34067333

RESUMEN

This work entailed the development, optimization, validation, and application of a novel analytical approach, using the bar adsorptive microextraction technique (BAµE), for the determination of the six most common tricyclic antidepressants (TCAs; amitriptyline, mianserin, trimipramine, imipramine, mirtazapine and dosulepin) in urine matrices. To achieve this goal, we employed, for the first time, new generation microextraction devices coated with convenient sorbent phases, polymers and novel activated carbons prepared from biomaterial waste, in combination with large-volume-injection gas chromatography-mass spectrometry operating in selected-ion monitoring mode (LVI-GC-MS(SIM)). Preliminary assays on sorbent coatings, showed that the polymeric phases present a much more effective performance, as the tested biosorbents exhibited low efficiency for application in microextraction techniques. By using BAµE coated with C18 polymer, under optimized experimental conditions, the detection limits achieved for the six TCAs ranged from 0.2 to 1.6 µg L-1 and, weighted linear regressions resulted in remarkable linearity (r2 > 0.9960) between 10.0 and 1000.0 µg L-1. The developed analytical methodology (BAµE(C18)/LVI-GC-MS(SIM)) provided suitable matrix effects (90.2-112.9%, RSD ≤ 13.9%), high recovery yields (92.3-111.5%, RSD ≤ 12.3%) and a remarkable overall process efficiency (ranging from 84.9% to 124.3%, RSD ≤ 13.9%). The developed and validated methodology was successfully applied for screening the six TCAs in real urine matrices. The proposed analytical methodology proved to be an eco-user-friendly approach to monitor trace levels of TCAs in complex urine matrices and an outstanding analytical alternative in comparison with other microextraction-based techniques.


Asunto(s)
Antidepresivos Tricíclicos/orina , Microextracción en Fase Sólida/métodos , Urinálisis/métodos , Adsorción , Materiales Biocompatibles/química , Carbón Orgánico/química , Cromatografía de Gases y Espectrometría de Masas , Humanos , Concentración de Iones de Hidrógeno , Iones , Límite de Detección , Microextracción en Fase Líquida/métodos , Polímeros/química , Polipropilenos/química , Reproducibilidad de los Resultados , Urinálisis/normas , Agua/química
5.
Molecules ; 25(6)2020 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-32235801

RESUMEN

We developed, optimized and validated a fast analytical cycle using high throughput bar adsorptive microextraction and microliquid desorption (HT-BAµE-µLD) for the extraction and desorption of ketamine and norketamine in up to 100 urine samples simultaneously, resulting in an assay time of only 0.45 min/sample. The identification and quantification were carried out using large volume injection-gas chromatography-mass spectrometry operating in the selected ion monitoring mode (LVI-GC-MS(SIM)). Several parameters that could influencing HT-BAµE were assayed and optimized in order to maximize the recovery yields of ketamine and norketamine from aqueous media. These included sorbent selectivity, desorption solvent and time, as well as shaking rate, microextraction time, matrix pH, ionic strength and polarity. Under optimized experimental conditions, suitable sensitivity (1.0 µg L-1), accuracy (85.5-112.1%), precision (≤15%) and recovery yields (84.9-105.0%) were achieved. Compared to existing methods, the herein described analytical cycle is much faster, environmentally friendly and cost-effective for the quantification of ketamine and norketamine in urine samples. To our knowledge, this is the first work that employs a high throughput based microextraction approach for the simultaneous extraction and subsequent desorption of ketamine and norketamine in up to 100 urine samples simultaneously.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/instrumentación , Ketamina/análogos & derivados , Ketamina/orina , Microextracción en Fase Líquida/métodos , Microextracción en Fase Sólida/métodos , Orina/química , Adsorción , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Ketamina/análisis , Ketamina/química , Límite de Detección , Reproducibilidad de los Resultados , Solventes/química , Agua/química
6.
Molecules ; 25(9)2020 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-32370134

RESUMEN

: In the present work we propose, for the first time, bar adsorptive microextraction coated with carbon-based phase mixtures, followed by microliquid desorption and high performance liquid chromatography-diode array detection (BAµE-µLD/HPLC-DAD) analysis, to enhance the performance of the determination of traces of benzotriazoles (BTRs), benzothiazoles (BTs), and benzenesulfonamide derivatives (BSDs) in environmental water matrices. Assessing six carbon-based sorbents (CA1, CN1, B test EUR, SX PLUS, SX 1, and R) with different selectivity properties allowed us to tailor the best phase mixture (R, 12.5%/CN1, 87.5%) that has convenient porosity, texture, and surface chemistry (pHPZC,mix ~6.5) for trace analysis of benzenesulfonamide, 1-hydroxybenzotriazole, 1H-benzotriazole, 5-methyl-1H-benzotriazole, benzothiazole, and 1,3-benzothiazol-2-ol chemicals in aqueous media. Optimized experimental conditions provided average recoveries ranging from 37.9% to 59.2%, appropriate linear dynamic ranges (5.0 to 120.0 µg L-1; r2 ≥ 0.9964), limits of detection between 1.0 and 1.4 µg L-1, and good precisions (relative standard deviation (RSD) ≤ 9.3%). The proposed methodology (BAµE(R, 12.5%/CN1, 87.5%)-µLD/HPLC-DAD) also proved to be a suitable sorption-based static microextraction alternative to monitor traces of BTRs, BTs, and BSDs in rain, waste, tap, and estuarine water samples. From the data obtained, the proposed approach showed that the BAµE technique with the addition of lab-made devices allows users to adapt the technique to use sorbents or mixtures of sorbents with the best selectivity characteristics whenever distinct classes of target analytes occur simultaneously in the same application.


Asunto(s)
Benzotiazoles/análisis , Carbono/química , Monitoreo del Ambiente/métodos , Microextracción en Fase Sólida , Sulfonamidas/química , Triazoles/análisis , Contaminantes Químicos del Agua/análisis , Cromatografía Líquida de Alta Presión , Monitoreo del Ambiente/instrumentación , Sensibilidad y Especificidad , Microextracción en Fase Sólida/instrumentación , Microextracción en Fase Sólida/métodos , Bencenosulfonamidas
7.
Molecules ; 24(5)2019 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-30866456

RESUMEN

Multi-spheres adsorptive microextraction using powdered activated carbons (ACs) was studied as a novel enrichment approach, followed by liquid desorption and high-performance liquid chromatography with diode array detection (MSAµE(AC)-LD/HPLC-DAD) to monitor caffeine (CAF) and acetaminophen (ACF) traces in environmental matrices. In this study, commercial activated carbons (N, NOX, and R) were tested, with the latter showing a much better performance for the analysis of both anthropogenic drugs. The main parameters affecting the efficiency of the proposed methodology are fully discussed using commercial AC(R). Textural and surface chemistry properties of the ACs sample were correlated with the analytical results. Assays performed on 30 mL of water samples spiked at 10 µg L-1 under optimized experimental conditions, yielding recoveries of 75.3% for ACF and 82.6% for CAF. The methodology also showed excellent linear dynamic ranges for both drugs with determination coefficients higher than 0.9976, limits of detection and quantification of 0.8⁻1.2 µg L-1 and 2.8⁻4.0 µg L-1, respectively, and suitable precision (RSD < 13.8%). By using the standard addition method, the application of the present method to environmental matrices, including superficial, sea, and wastewater samples, allowed very good performance at the trace level. The proposed methodology proved to be a feasible alternative for polar compound analysis, showing to be easy to implement, reliable, and sensitive, with the possibility to reuse and store the analytical devices loaded with the target compounds for later analysis.


Asunto(s)
Acetaminofén/aislamiento & purificación , Cafeína/aislamiento & purificación , Microextracción en Fase Sólida/métodos , Agua/análisis , Adsorción , Carbón Orgánico/química , Cromatografía Líquida de Alta Presión/métodos , Límite de Detección , Contaminantes Químicos del Agua/aislamiento & purificación
8.
Pharm Biol ; 55(1): 1348-1357, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28301958

RESUMEN

CONTEXT: Several Polygonum species (Polygonaceae) are used in traditional medicine in Asia, Europe and Africa to treat inflammation and diabetes. OBJECTIVE: Evaluate the in vitro antioxidant, anti-inflammatory and antidiabetic potential of methanol and dichloromethane extracts of leaves and roots of the halophyte Polygonum maritimum L. MATERIAL AND METHODS: Antioxidant activity was determined (up to 1 mg/mL) as radical-scavenging activity (RSA) of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), copper (CCA) and iron (ICA) chelating activities and iron reducing power (FRAP). NO production was measured in lipopolysaccharide (LPS)-stimulated macrophages for 24 h at concentrations up to 100 µg/mL and antidiabetic potential was assessed by α-amylase and α-glucosidase inhibition (up to 10 mg/mL) assays. The phytochemical composition of the extracts was determined by gas chromatography-mass spectrometry (GC-MS). RESULTS: The methanol leaf extract had the highest activity against DPPH• (IC50 = 26 µg/mL) and ABTS+• (IC50 = 140 µg/mL), FRAP (IC50 = 48 µg/mL) and CCA (IC50 = 770 µg/mL). Only the dichloromethane leaf extract (LDCM) showed anti-inflammatory activity (IC50 = 48 µg/mL). The methanol root (IC50 = 19 µg/mL) and leaf (IC50 = 29 µg/mL) extracts strongly inhibited baker's yeast α-glucosidase, but LDCM had higher rat's α-glucosidase inhibition (IC50 = 2527 µg/mL) than acarbose (IC50 = 4638 µg/mL). GC-MS analysis identified ß-sitosterol, stigmasterol, 1-octacosanol and linolenic acid as possible molecules responsible for the observed bioactivities. CONCLUSIONS: Our findings suggest P. maritimum as a source of high-value health promoting commodities for alleviating symptoms associated with oxidative and inflammatory diseases, including diabetes.


Asunto(s)
Antiinflamatorios/farmacología , Hipoglucemiantes/farmacología , Extractos Vegetales/farmacología , Polygonum , Animales , Antioxidantes/farmacología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Cromatografía de Gases y Espectrometría de Masas , Ratones , Fitoquímicos/análisis , Polygonum/química , Ratas
9.
J Sep Sci ; 39(4): 756-61, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26632142

RESUMEN

This manuscript addresses the determination of triazines (ametryn, atrazine, simazine, and terbutryn) in corn matrices using bar adsorptive microextraction coated with a selective molecularly imprinted polymer phase following microliquid desorption and high-performance liquid chromatography with diode array detection. The molecularly imprinted polymer was synthesized using atrazine as a template and methacrylic acid as a functional monomer. Assays performed in 25 mL of ultrapure water samples spiked at 8.0 µg/L yielded 80-120 % recoveries under the evaluated experimental conditions. The method showed an accuracy (0.2 < bias < 17.9%), precision (relative standard deviation <17.4%), convenient detection (0.2 µg/L), and quantification (0.7 µg/L) limits, as well as linear dynamic ranges (0.8-24.0 µg/L) with remarkable determination coefficients (R(2) > 0.9926). The proposed analytical method was applied to monitor triazines in three types of corn matrices using the standard addition methodology. Experiments performed in corn samples spiked with triazines at the trace level (8.0 µg/kg of each analyte) gave rise to recoveries (81.0-119.4%) with good reproducibility and robustness. The proposed methodology is also easy to implement and showed to be a good analytical alternative to monitor triazines in complex matrices, when compared with other sorption-based microextraction techniques.


Asunto(s)
Polímeros/química , Microextracción en Fase Sólida/métodos , Triazinas/química , Adsorción , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Gasolina , Geles/química , Hidrocarburos/química , Microextracción en Fase Líquida , Tamaño de la Partícula , Reproducibilidad de los Resultados , Dióxido de Silicio/química , Temperatura , Zea mays
10.
Mar Drugs ; 14(10)2016 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-27727161

RESUMEN

Among marine organisms, sponges are the richest sources of pharmacologically-active compounds. Stemming from a previous lead discovery program that gathered a comprehensive library of organic extracts of marine sponges from the off-shore region of Portugal, crude extracts of Erylus cf. deficiens collected in the Gorringe Bank (Atlantic Ocean) were tested in the innovative high throughput screening (HTS) assay for inhibitors of indoleamine 2,3-dioxygenase (IDO) and showed activity. Bioassay guided fractionation of the dichloromethane extract led to the isolation of four new glycolipids, named erylusamide A-D. The structures of the isolated compounds were established by 1D and 2D nuclear magnetic resonance (NMR) spectroscopy, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) and chemical derivatization. The metabolites shared a pentasaccharide moiety constituted by unusual highly acetylated ᴅ-glucose moieties as well as ᴅ-xylose and ᴅ-galactose. The aglycones were unprecedented long chain dihydroxyketo amides. Erylusamides A, B and D differ in the length of the hydrocarbon chain, while erylusamide C is a structural isomer of erylusamide B.


Asunto(s)
Glucolípidos/química , Animales , Océano Atlántico , Células COS/efectos de los fármacos , Chlorocebus aethiops , Glucolípidos/farmacología , Poríferos , Portugal , Relación Estructura-Actividad
11.
Mar Drugs ; 13(6): 3531-49, 2015 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-26047482

RESUMEN

Four lipid-rich microalgal species from the Red Sea belonging to three different genera (Nannochloris, Picochlorum and Desmochloris), previously isolated as novel biodiesel feedstocks, were bioprospected for high-value, bioactive molecules. Methanol extracts were thus prepared from freeze-dried biomass and screened for different biological activities. Nannochloris sp. SBL1 and Desmochloris sp. SBL3 had the highest radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl, and the best copper and iron chelating activities. All species had potent butyrylcholinesterase inhibitory activity (>50%) and mildly inhibited tyrosinase. Picochlorum sp. SBL2 and Nannochloris sp. SBL4 extracts significantly reduced the viability of tumoral (HepG2 and HeLa) cells with lower toxicity against the non-tumoral murine stromal (S17) cells. Nannochloris sp. SBL1 significantly reduced the viability of Leishmania infantum down to 62% (250 µg/mL). Picochlorum sp. SBL2 had the highest total phenolic content, the major phenolic compounds identified being salicylic, coumaric and gallic acids. Neoxanthin, violaxanthin, zeaxanthin, lutein and ß-carotene were identified in the extracts of all strains, while canthaxanthin was only identified in Picochlorum sp. SBL2. Taken together, these results strongly suggest that the microalgae included in this work could be used as sources of added-value products that could be used to upgrade the final biomass value.


Asunto(s)
Biomasa , Microalgas/química , Extractos Vegetales/farmacología , Animales , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Butirilcolinesterasa/efectos de los fármacos , Quelantes/aislamiento & purificación , Quelantes/farmacología , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de la Colinesterasa/farmacología , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/farmacología , Células HeLa , Células Hep G2 , Humanos , Océano Índico , Lípidos/química , Metanol/química , Fenoles/aislamiento & purificación , Fenoles/farmacología
12.
Electrophoresis ; 35(17): 2488-94, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24789174

RESUMEN

In this contribution, bar adsorptive microextraction coated with a mixed-mode anion exchange/RP followed by liquid desorption was combined for the first time with a capillary electrophoresis-diode array detection system (BAµE(MAX)-LD/CE-DAD), for the determination of phenolic acids in food matrices, using chlorogenic, ferulic, cumaric, and caffeic acids as model compounds. Assays performed in aqueous media spiked at the 0.8 mg/L level yielded average recoveries up to 40% for all four phenolic acids, under optimized experimental conditions. The analytical performance showed also good precision (RSD < 15%), convenient LODs (18.0-85.0 µg/L) and linear dynamic ranges (0.8-8.0 mg/L) with convenient determination coefficients (r(2) > 0.9900). By using the standard addition method, the application to food matrices such as green tea, red fruit juice, and honey allowed very good performances for the determination of minor amounts of phenolic acids. The proposed methodology proved to be a suitable alternative for the analysis of polar to ionic compounds, showing to be easy to implement, reliable, sensitive, and requiring a low sample volume to determine phenolic acids in food samples.


Asunto(s)
Bebidas/análisis , Fraccionamiento Químico/métodos , Cinamatos/análisis , Electroforesis Capilar/métodos , Frutas/química , Miel/análisis , Límite de Detección , Reproducibilidad de los Resultados , Té/química
13.
Phytother Res ; 28(9): 1329-34, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24633846

RESUMEN

Artemisia gorgonum (Asteraceae) is an endemic plant to the Cape Verde islands and plays an important role in traditional medicine. The chloroform extract of the plant aerial parts afforded six sesquiterpene lactones, two methoxylated flavonoids, two lignans, and one tetracyclic triterpene, which were isolated by chromatographic methods and their structure established by physical and spectroscopic techniques. The cytotoxic activity of the three major constituents, namely, arborescin, artemetin, and sesamin, was evaluated on neuroblastoma (SH-SY5Y), hepatocarcinoma (HepG2), and nontumoral bone marrow stromal (S17) cell lines. The application of different concentrations of the compounds significantly decreased tumor cells viability at different extents, especially at the highest concentrations tested. Arborescin is the most promising compound as it was able to reduce tumoral cell viability with an IC50 significantly lower (229-233 µM; p < 0.01) than that of S17 cells (445 µM). Arborescin and artemetin were less toxic to nontumoral cells than the antitumoral drug tested, etoposide. Our results indicate that arborescin has a significant cytotoxic activity in vitro, more pronounced on the cancer cell lines, confirming A. gorgonum as a source of potential antitumoral molecules.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Artemisia/química , Dioxoles/farmacología , Flavonoides/farmacología , Lignanos/farmacología , Extractos Vegetales/farmacología , Sesquiterpenos de Guayano/farmacología , Animales , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular , Línea Celular Tumoral , Dioxoles/aislamiento & purificación , Flavonoides/aislamiento & purificación , Humanos , Lignanos/aislamiento & purificación , Ratones , Componentes Aéreos de las Plantas , Extractos Vegetales/química , Sesquiterpenos de Guayano/aislamiento & purificación
14.
Molecules ; 19(7): 9369-79, 2014 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-24995922

RESUMEN

Bar adsorptive microextraction combined with liquid desorption followed by high performance liquid chromatography with diode array detection (BAµE-LD/HPLC-DAD) is proposed for the determination of trace levels of five phenol compounds (3-nitrophenol, 4-nitrophenol, bisphenol-A, 4-n-octylphenol and 4-n-nonylphenol) in surface water matrices. By using a polystyrene-divinylbenzene copolymer (PS-DVB) sorbent phase, high selectivity and efficiency is achieved even against polydimethylsiloxane through stir bar sorptive extraction. Assays performed by BAµE(PS-DVB)-LD/HPLC-DAD on 25 mL water samples spiked at the 10.0 µg/L levels yielded recoveries over 88.0%±5.7% for all five analytes, under optimized experimental conditions. The analytical performance showed good precision (RSD<15%), detection limits of 0.25 µg/L and linear dynamic ranges (1.0-25.0 µg/L) with determination coefficient higher than 0.9904. By using the standard addition method, the application of the present method to surface water matrices allowed very good performances at the trace level. The proposed methodology proved to be a suitable alternative to monitor phenol compounds in surface water matrices, showing to be easy to implement, reliable, sensitive and requiring a low sample volume.


Asunto(s)
Disruptores Endocrinos/análisis , Fenoles/análisis , Contaminantes Químicos del Agua/análisis , Adsorción , Cromatografía Líquida de Alta Presión , Límite de Detección , Microextracción en Fase Sólida
15.
J Sci Food Agric ; 93(11): 2707-14, 2013 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-23553824

RESUMEN

BACKGROUND: There is a growing interest in industry to replace synthetic chemicals by natural products with bioactive properties. Aromatic plants are excellent sources of bioactive compounds that can be extracted using several processes. As far as oregano is concerned, studies are lacking addressing the effect of extraction processes in bioactivity of extracts. This study aimed to characterise the in vitro antioxidant and antibacterial properties of oregano (Origanum vulgare) essential oil and extracts (in hot and cold water, and ethanol), and the chemical composition of its essential oil. RESULTS: The major components of oregano essential oil were carvacrol, ß-fenchyl alcohol, thymol, and γ-terpinene. Hot water extract had the strongest antioxidant properties and the highest phenolic content. All extracts were ineffective in inhibiting the growth of the seven tested bacteria. In contrast, the essential oil inhibited the growth of all bacteria, causing greater reductions on both Listeria strains (L. monocytogenes and L. innocua). CONCLUSION: O. vulgare extracts and essential oil from Portuguese origin are strong candidates to replace synthetic chemicals used by the industry.


Asunto(s)
Aceites Volátiles/química , Origanum/química , Extractos Vegetales/química , Aceites de Plantas/química , Antioxidantes/química
16.
Molecules ; 17(3): 3082-92, 2012 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-22410418

RESUMEN

Acetylcholinesterase inhibition, antioxidant and cytotoxic activities of Hedychium gardnerianum leaf essential oils from S. Miguel Island were determined. All the oils inhibited acetylcholinesterase, with IC(50) values of approximately 1 mg/mL, showing no statistical differences between collection sites. Three oils presented mixed inhibition, whilst one was almost truly competitive. This activity can be attributed to the presence of sesquiterpenes, which constituted more than 60% of the composition of the oils. Regarding the antioxidant activity as measured by the DPPH method, all the oils presented activities similar to reference compounds, although with statistical differences between collection sites. Cytotoxicity measured using Artemia salina classified these oils as moderately toxic, with LC(50) values ranging from 300 to 500 µg/mL. These results indicate a possible application of these oils in aromatherapy as coadjuvants in the treatment of cognitive diseases such as Alzheimer, since they may contribute to increase acetylcholine in cholinergic neurons and simultaneously fight deleterious oxidations responsible by neurological degeneration.


Asunto(s)
Inhibidores de la Colinesterasa/química , Depuradores de Radicales Libres/química , Aceites Volátiles/química , Aceites de Plantas/química , Terpenos/química , Zingiberaceae/química , Acetilcolinesterasa/química , Animales , Artemia/efectos de los fármacos , Compuestos de Bifenilo/química , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de la Colinesterasa/farmacología , Citotoxinas/química , Citotoxinas/aislamiento & purificación , Citotoxinas/farmacología , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/farmacología , Cinética , Dosificación Letal Mediana , Aceites Volátiles/aislamiento & purificación , Aceites Volátiles/farmacología , Picratos/química , Hojas de la Planta/química , Aceites de Plantas/aislamiento & purificación , Aceites de Plantas/farmacología , Terpenos/aislamiento & purificación
17.
J Sci Food Agric ; 91(9): 1554-60, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21445865

RESUMEN

BACKGROUND: This study aimed to evaluate the antioxidant and antimicrobial activity of extracts (aqueous, ethanolic and essential oil) from Satureja montana and to characterise the chemical composition of its essential oil. RESULTS: Satureja montana L. essential oil had relatively high antimicrobial activities against the seven species of bacteria tested. In contrast, aqueous extracts did not reveal antibacterial activity, and the ethanol extract was not effective against Salmonella typhimurium. The major volatile constituents of the essential oil were carvacrol (306 g L(-1)), thymol (141 g L(-1)), and carvacrol methyl ether (63 g L(-1)). The strongest antioxidant capacity was obtained with the hot water extracts of S. montana, whereas the plant essential oil revealed the highest phenolic content. CONCLUSION: The findings indicate that the bioactive extracts of S. montana have strong potential for use as natural antimicrobials and antioxidants in the preservation of processed food.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Monoterpenos/farmacología , Aceites Volátiles/química , Fenoles/farmacología , Extractos Vegetales/farmacología , Satureja/química , Antibacterianos/análisis , Antioxidantes/análisis , Bacterias/efectos de los fármacos , Cimenos , Monoterpenos/análisis , Fenoles/análisis , Extractos Vegetales/química , Timol/análisis , Timol/farmacología
18.
Plant Foods Hum Nutr ; 66(1): 78-84, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21399924

RESUMEN

This work aimed to evaluate the phytochemical content and to determine the antioxidant and cytotoxic activities of methanol extracts of the carob tree (Ceratonia siliqua L.) germ flour. The extracts were rich in phenolic compounds, had considerable antioxidant activity, and reduced the viability of cervical (HeLa) cancer cells. The chemical content and the biological activities of the extracts were significantly affected by gender and cultivar. Female cultivar Galhosa had the highest levels of phenolic compounds, and the highest antioxidant activity. Extracts from the hermaphrodite trees and from the female cultivars Galhosa and Costela/Canela exhibited the highest cytotoxic activity. The most abundant compound was theophylline. The phenolic content was correlated to both antioxidant and cytotoxic activities. Our findings provide new knowledge about the health implications of consuming food supplemented with carob germ flour.


Asunto(s)
Antioxidantes/farmacología , Fabaceae/química , Galactanos/farmacología , Mananos/farmacología , Extractos Vegetales/farmacología , Gomas de Plantas/farmacología , Teofilina/farmacología , Galactanos/química , Células HeLa , Humanos , Mananos/química , Fenoles/análisis , Fenoles/farmacología , Extractos Vegetales/análisis , Gomas de Plantas/química , Teofilina/análisis
19.
Plants (Basel) ; 10(3)2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33809590

RESUMEN

In our endeavor to identify salt-tolerant plants with potential veterinary uses in ruminants' production strategies, we focused on Cladium mariscus L. Pohl (sawgrass), due to its high total phenolic and tannin content, anti-radical properties, and ethnomedicinal uses. Aerial parts were collected along the year in Southern Portugal and evaluated for the nutritional profile and in vitro organic matter digestibility (IVOMD), aiming for its use as feed. Acetone extracts were appraised for total contents in phenolics (TPC), flavonoids (TFC), and tannins (CTC), as well as the chemical composition by HPLC-DAD and in vitro antioxidant and anti-inflammatory properties, targeting its exploitation as phytotherapeutic products. Sawgrass biomass has a limited nutritive value, due to its high neutral detergent fiber (NDF; 596-690 g kg-1 dry matter (DM)) and acid detergent fiber (ADF; 330-418 g kg-1 DM) contents, low crude protein (51.8-87.3 g kg-1 DM) and IVOMD (172-317 g kg-1 organic matter (OM)). Despite differences among seasons, the mineral profile was adequate. The extracts were rich in TPC (88-112 mg g-1), CTC (115-169 mg g-1), and TFC (18.5-20.2 mg g-1), and displayed significant antioxidant capacity, particularly in summer and autumn, whilst no seasonal influence was detected for anti-inflammatory properties (30% reduction of nitric oxide production). Eleven phenolics were quantified: chlorogenic, ferulic, and syringic acids were the most abundant, especially in the autumn sample. Overall, despite the low nutritional interest, sawgrass extracts hold the potential as a source of antioxidant and anti-inflammatory phenolic compounds.

20.
Nat Prod Res ; 35(22): 4753-4756, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32013559

RESUMEN

This work reports for the first time the in vitro anti-oxidant (towards DPPH, ABTS, copper and iron), enzymatic inhibitory (on AChE, BuChE, α-glucosidase, α-amylase and tyrosinase), cytotoxicity (towards HepG2 and HEK 293 cells), and metabolomics (by HPLC-MS) of extracts from organs of Malcolmia littorea (L.) R.Br. Extracts were constituted mainly by phenolic acids and flavonoids, and main compounds were salicylic acid and luteolin-7-O-glucoside. Samples showed reduced radical scavenging and metal chelating capacity, and only the methanol extracts reduced iron. The root's ethanol and methanol extracts, and the aerial organ's ethanol extract exhibited the highest AChE inhibition. The root's ethanol extract displayed dual anti-cholinesterase activity. Samples showed a low capacity to inhibit α-amylase, but a high α-glucosidase inhibition was obtained with the root's and flower's ethanol extracts, and flower's methanol extract. Overall, samples displayed a high inhibition against tyrosinase, reduced HepG2 cellular viability and were less toxic towards HEK 293 cells.


Asunto(s)
Antioxidantes , Brassicaceae , Antioxidantes/farmacología , Inhibidores Enzimáticos/farmacología , Células HEK293 , Humanos , Fitoquímicos , Extractos Vegetales/farmacología , Plantas Tolerantes a la Sal
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