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1.
Foods ; 13(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38672892

RESUMO

Disphyma crassifolium, commonly known as sea fingers, is a halophyte plant recently introduced in gourmet cuisine. The present study aims to extract the bioactive compounds of D. crassifolium using ultrasound-assisted extraction and employing green solvents (water and ethanol). The antioxidant/antiradical activities, scavenging capacity against reactive species, phenolic profile, and intestinal effects were evaluated. The highest total phenolic (53.13 mg of gallic acid equivalent (GAE)/g on dry weight (dw)) and flavonoid contents (18.98 mg of catechin equivalent (CE)/g dw) as well as antioxidant (149.69 µmol of ferrous sulphate equivalent (FSE)/g dw) and antiradical capacities (9.37 mg of ascorbic acid equivalent (AAE)/g dw) were achieved for the alcoholic extract. Moreover, the alcoholic extract exhibited an efficient uptake of HOCl (IC50 = 1.97 µg/mL) and ROO• (0.34 µmol of Trolox equivalent (TE)/mg dw). A total of 34 phenolic compounds were identified in the extracts, with flavonols (isorhamnetin-3-O-rutinoside, quercetin-3-O-galactoside, and myricetin), flavanols (catechin), and phenolic acids (gallic and ellagic acids) being the principal classes. The intestinal cell viability assays attested that the alcoholic extract presented the lowest IC50 values (289.82 and 35.77 µg/mL for HT29-MTX and Caco-2), showing probable anticancer activity. These results emphasize the potential of D. crassifolium as a nutraceutical ingredient.

2.
Foods ; 13(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38275684

RESUMO

Blueberry fruits have been widely explored for their rich composition of bioactive compounds with recognized health benefits. In contrast, blueberry pruning waste (BPW), generated during the pruning stages of blueberries, has been typically overlooked, even though it can represent a potential source of natural antioxidants. This study aims to characterize the value-added compounds extracted from BPW using green techniques, namely microwave-assisted and subcritical water extraction. The total phenolic content ranged from 157 ± 5 to 335 ± 12 mg GAE/g dw, while the radical scavenging activity determined by a DPPH assay varied from 223 ± 21 to 453 ± 21 mg Trolox equivalents/g dw. Additionally, to ensure the safe application of BPW and its extracts, a screening of pesticides and several environmental contaminants was conducted. Chlorpyrifos-methyl was quantified at a concentration of 4.27 µg/kg in a Bluecrop variety collected in 2019; however, none of the studied compounds were found in the extracts. Despite the presence of a pesticide, this level was below the maximum residue limits for blueberry crops. The results of this study demonstrated the potential of this agro-industrial residue as a natural source of bioactive compounds with high antioxidant activity for food industry applications.

3.
Foods ; 12(5)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36900510

RESUMO

Global production of exotic fruits has been growing steadily over the past decade and expanded beyond the originating countries. The consumption of exotic and new fruits, such as kiwano, has increased due to their beneficial properties for human health. However, these fruits are scarcely studied in terms of chemical safety. As there are no studies on the presence of multiple contaminants in kiwano, an optimized analytical method based on the QuEChERS for the evaluation of 30 multiple contaminants (18 pesticides, 5 polychlorinated biphenyls (PCB), 7 brominated flame retardants) was developed and validated. Under the optimal conditions, satisfactory extraction efficiency was obtained with recoveries ranging from 90% to 122%, excellent sensitivity, with a quantification limit in the range of 0.6 to 7.4 µg kg-1, and good linearity ranging from 0.991 to 0.999. The relative standard deviation for precision studies was less than 15%. The assessment of the matrix effects showed enhancement for all the target compounds. The developed method was validated by analyzing samples collected from Douro Region. PCB 101 was found in trace concentration (5.1 µg kg-1). The study highlights the relevance of including other organic contaminants in monitoring studies in food samples in addition to pesticides.

4.
Int J Mol Sci ; 23(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36499282

RESUMO

Oral mucositis (OM), a common side effect of oncological treatment, is an oral mucosal disorder characterized by painful ulcerations and increased risk of infection. The use of natural antioxidants to suppress the redox imbalance responsible for the OM condition has emerged as an interesting approach to prevent/treat OM. This study aims to explore the chestnut (Castana sativa) shells as potential active ingredient against OM. Therefore, chestnut shells were extracted at different temperatures (110-180 °C) by Subcritical Water Extraction (SWE), aiming to recover antioxidants. The extracts were also evaluated against microorganisms present in the oral cavity as well as on human oral cell lines (TR146 and HSC3). The highest phenolic content was obtained with the extraction temperature of 110 °C, exhibiting the best antioxidant/antiradical activities and scavenging efficiencies against HOCl (IC50 = 4.47 µg/mL) and ROO• (0.73 µmol TE/mg DW). High concentrations of phenolic acids (e.g., gallic and protocatechuic acids) and flavanoids (catechin, epicatechin and rutin) characterized the phenolic profile. The antimicrobial activity against several oral microorganisms present in the oral cavity during OM, such as Streptococcus, Staphylococcus, Enterococcus, and Escherichia, was demonstrated. Finally, the effects on HSC3 and TR146 cell lines revealed that the extract prepared at 110 °C had the lowest IC50 (1325.03 and 468.15 µg/mL, respectively). This study highlights the potential effects of chestnut shells on OM.


Assuntos
Extratos Vegetais , Estomatite , Humanos , Extratos Vegetais/farmacologia , Antioxidantes/farmacologia , Fenóis/farmacologia , Nozes/química , Estomatite/tratamento farmacológico
5.
Antioxidants (Basel) ; 11(4)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35453448

RESUMO

This study aims to evaluate the optimal ultrasound-assisted extraction (UAE) conditions of antioxidants polyphenols from Actinidia arguta (Siebold & Zucc.) Planch. Ex Miq. (kiwiberry) leaves using a response surface methodology (RSM). The effects of solid:liquid ratio (2.5-10.0% w/v), time (20-60 min), and intensity (30-70 W/m2) on the total phenolic content (TPC) and antioxidant/antiradical activities were investigated. The optimal UAE conditions were achieved using a solid:liquid ratio of 10% (w/v) and an ultrasonic intensity of 30 W/m2 for 31.11 min. The results demonstrated that the optimal extract showed a high TPC (97.50 mg of gallic acid equivalents (GAE)/g dw) and antioxidant/antiradical activity (IC50 = 249.46 µg/mL for ABTS assay; IC50 = 547.34 µg/mL for DPPH assay; 1440.13 µmol of ferrous sulfate equivalents (FSE)/g dw for ferric reducing antioxidant power (FRAP)) as well as a good capacity to scavenge superoxide and hypochlorous acid (respectively, IC50 = 220.13 µg/mL and IC50 =10.26 µg/mL), which may be related with the 28 phenolic compounds quantified. The in vitro cell assay demonstrated that the optimal extract did not decrease the keratinocytes' (HaCaT) viability, while the fibroblasts' (HFF-1) viability was greater than 70.63% (1000 µg/mL). This study emphasizes the great potential of kiwiberry leaves extracted by UAE for skin application.

6.
Sci Total Environ ; 830: 154600, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35337875

RESUMO

Grapes represent one of the most produced fruit crops around the world leading to the generation of large amounts of vine-canes as a side product, with no current economically profitable application. However, vine-canes have been demonstrated to be natural sources of phenolic compounds with numerous health benefits associated, with several potential applications. Therefore, new ambitious applications focused on their re-use are needed, targeting a sustainable process that simultaneous produces functional products and mitigates the waste generation. This review gives to the readers a complete summary about the state of the art regarding the vine-canes extracts research. Vine-canes phenolic composition is addressed and related to the health benefits exhibited. This review comprises studies from the past two decades reporting the extraction processes to recover vine-cane phenolic compounds, including conventional and environmentally friendly technologies and discussing their advantages and disadvantages. The conditions that favour the extraction process for vine-cane polyphenols for each technique were also deeply explored for the first time, enabling to the reader apply only the best parameters to achieve the highest yields without huge investment in optimizations procedures. Furthermore, a correlation between the bioactive properties of the vine-cane extracts and their applications in multiple fields is also critically presented.


Assuntos
Fenóis , Vitis , Antioxidantes , Extratos Vegetais , Polifenóis
7.
Sci Total Environ ; 791: 148395, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34412412

RESUMO

Every year, after grape harvesting, high quantities of vine-canes are generated. Due to the high amount of bioactive compounds present in this woody material, several studies reported their potential to be used in different sustainable applications. However, before employing vine-canes in this kind of products, their safety needs to be assessed. A robust method for identification and quantification of 30 environmental contaminants (12 organochloride pesticides (OCPs), 6 organophosphorus pesticides (OPPs), 5 polychlorinated biphenyls (PCBs) and 7 brominated flame retardants (BFRs)) in vine-canes was developed. For that, the extraction and clean-up procedures were optimized, namely the vine-canes size, the QuEChERS (quick, easy, cheap, effective, rugged and safe) composition and the amount of carbon used in the dispersive-solid phase extraction (d-SPE). Suitable analytical parameters were obtained: linearity (r2) >0.99 for all the studied compounds and for the solvent and matrix-matched standards; relative standard deviation (RSD) below 14%; and mean recoveries for two spiking levels (10 and 20 µg/kg) between 75 and 103%, excepting for the PCBs that ranged between 59 and 105%. The limit of detection (LOD) and quantification (LOQ) ranged between 0.38 and 1.09 and 1.26 to 3.64 µg/kg, respectively. Regarding the analysis of 19 vine-cane samples, corresponding to four different varieties (Touriga Nacional, Tinta Roriz, Alvarinho, and Loureiro) collected in four different years in the North of Portugal, five contaminants (aldrin, 2,2-bis(4-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE), α-hexachlorocyclohexane (α-HCH), 2,4,4'-trichlorobiphenyl (PCB28), and 2,2',4,5,5'-pentachlorobiphenyl (PCB101)) were detected. However, only α-HCH (5.85 ± 0.32 to 5.99 ± 0.25 µg/kg) and aldrin (2.44 ± 0.15 µg/kg) were quantified above the LOQ. The screening of environmental contaminants in vine-canes is essential to waste valorization, especially if the goal is to apply them in products for human consumption.


Assuntos
Praguicidas , Bengala , Fazendas , Humanos , Compostos Organofosforados , Portugal
8.
Foods ; 9(7)2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32635200

RESUMO

This work focused on evaluating the possibility of using vineyard pruning wastes from two Portuguese Vitis vinifera varieties; Touriga Nacional (TN) and Tinta Roriz (TR), as new potential ingredients for the nutraceutical industry. An environmentally friendly extraction technique; namely subcritical-water extraction (SWE), was employed. The overall results indicate that phenolic acids were the major class of compounds quantified; being gallic acid the principal one. The highest value for total phenolic content (TPC) was obtained for the TR extract at 250 °C (181 ± 12 mg GAE/g dw). In terms of antioxidant activity; the DPPH values for the extracts obtained at 250 °C were approximately 4-fold higher than the ones obtained at 125 °C; with TR extract presenting the highest value (203 ± 22 mg TE/g dw). Thus, the TR extract obtained through SWE at 250 °C was selected to evaluate the scavenging activity and the in vitro effects on cells due to the best results achieved in the previous assays. This extract presented the ability to scavenge reactive oxygen species (O2●-, HOCl and ROO●). No adverse effects were observed in HFF-1 viability after exposure to extract concentrations below 100 µg/mL. This work demonstrated that vine-canes extracts could be a potential ingredient to nutraceutical industry.

9.
Molecules ; 25(7)2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32290053

RESUMO

Wine production generates large amounts of vine-canes, a devalued by-product that could be used for the recovery of bioactive compounds. In this work, two vine-canes varieties, namely Touriga Nacional (TN) and Tinta Roriz (TR), were submitted to different ultrasound-assisted extraction (UAE) conditions. The highest phenolic and flavonoid content was observed for TR extract obtained at lab-scale without an ice bath and pilot-scale after 60 min of extraction (32.6 ± 2.1 and 26.0 ± 1.5 mg gallic acid equivalent/g dry weight (dw) and 9.5 ± 0.6 and 8.3 ± 0.8 mg epicatechin equivalents/g dw, respectively). Further, all extracts demonstrated a high antioxidant activity to scavenge DPPH free radicals with the best value reached by TR at the lab-scale without an ice bath after 30 min and pilot-scale extraction after 60 min (34.2 ± 2.4 and 33.4 ± 2.1 mg trolox equivalents/g dw, respectively). Extracts phenolic composition were also evaluated by HPLC, demonstrating that resveratrol, myricetin and catechin were the main compounds. According to our knowledge, this is the first time that a pilot scale of UAE of phenolic compounds from vine-canes was performed. This paper represents an important step to the use of UAE as an industrial process to recover bioactive compounds.


Assuntos
Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Fracionamento Químico , Ondas Ultrassônicas , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Produtos Biológicos/farmacologia , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Polifenóis/química , Polifenóis/isolamento & purificação , Polifenóis/farmacologia , Vinho
10.
Sci Total Environ ; 634: 831-842, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29653427

RESUMO

Since annually a high amount of wastes is produced in vine pruning, the aim of this study was to evaluate the potential of vine shoots from two Portuguese grape varieties (Touriga Nacional - TN and Tinta Roriz - TR) to be used as a natural source of phenolic compounds. To reach this goal, three techniques were explored, namely microwave-assisted extraction (MAE), subcritical water extraction (SWE) and conventional extraction (CE). The phenolic composition of the extracts, antioxidant and biological activities were evaluated by spectrophotometry and chromatography. MAE and SWE produced the highest concentrated extracts. TR vine shoot variety had the highest antioxidant activity and total phenolic (32.1±0.9mggallicacidequivalents/g dry sample), as well as flavonoid content (18.7±1.2mgepicatechinequivalents/g dry sample). For the first time, the biological activity of the vine shoot extracts was tested. Results demonstrated that all of them had antimicrobial potential against different bacteria and yeasts, and the ability of inhibiting α-amylase and acetylcholinesterase enzymes, with MAE TR extracts being the most efficient. HPLC analysis enabled the identification of different phenolic compounds, with gallic acid, catechin, myricetin and kaempferol-3-O-rutinoside being the main contributors to the phenolic composition. Portuguese vine shoot wastes could serve as easily accessible source of natural antioxidants for the food or pharmaceutical industries.


Assuntos
Extratos Vegetais/análise , Resíduos/análise , Antibacterianos/análise , Anti-Infecciosos/análise , Flavonoides , Ácido Gálico , Recursos Naturais , Fenóis/análise , Portugal , Vitis , Vinho
11.
Phytochem Anal ; 28(4): 297-304, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28124812

RESUMO

INTRODUCTION: Salting-out assisted liquid-liquid extraction (SALLE) is a technique that, although simple and not requiring any complex equipment, is very powerful and versatile. It has obtained growing interest in bioanalysis particularly when combined with chromatographic techniques. OBJECTIVES: Herein, fennel seeds (Foeniculum vulgare Mill.) were used as a case-study to show the application of SALLE in phytochemical analysis. MATERIAL AND METHODS: SALLE combined with HPLC-UV-MS/MS and GC-MS. RESULTS: By HPLC-UV-MS/MS analysis of the organic extract it was possible to identify various phenolic compounds, including quercetin derivatives, caffeic acid, p-coumaric acid and chlorogenic acid. The main compounds identified by GC-MS were estragole, fenchone, anisaldehyde, anethole, benzaldehyde, camphor and apiole. CONCLUSION: HPLC and GC analysis of the extracts showed that it is possible to isolate, in only one step, a wide range of compounds with distinct properties, allowing a detailed phytochemical analysis. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Foeniculum/química , Extração Líquido-Líquido , Compostos Fitoquímicos/análise , Extratos Vegetais/análise , Fenóis/análise , Sementes/química , Espectrometria de Massas em Tandem
12.
Anal Bioanal Chem ; 403(4): 1019-29, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22274285

RESUMO

This paper reports a novel application of microwave-assisted extraction (MAE) of polyphenols from brewer's spent grains (BSG). A 2(4) orthogonal composite design was used to obtain the optimal conditions of MAE. The influence of the MAE operational parameters (extraction time, temperature, solvent volume and stirring speed) on the extraction yield of ferulic acid was investigated through response surface methodology. The results showed that the optimal conditions were 15 min extraction time, 100 °C extraction temperature, 20 mL of solvent, and maximum stirring speed. Under these conditions, the yield of ferulic acid was 1.31 ± 0.04% (w/w), which was fivefold higher than that obtained with conventional solid-liquid extraction techniques. The developed new extraction method considerably reduces extraction time, energy and solvent consumption, while generating fewer wastes. HPLC-DAD-MS analysis indicated that other hydroxycinnamic acids and several ferulic acid dehydrodimers, as well as one dehydrotrimer were also present, confirming that BSG is a valuable source of antioxidant compounds.


Assuntos
Grão Comestível/química , Extração Líquido-Líquido/métodos , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Polifenóis/análise , Polifenóis/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Extração Líquido-Líquido/instrumentação , Espectrometria de Massas/métodos , Micro-Ondas
13.
J Chromatogr A ; 1189(1-2): 398-405, 2008 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-18035361

RESUMO

The pattern of the monomeric and oligomeric flavan-3-ols for 10 barley varieties and the corresponding malts were identified and quantified using high-performance liquid chromatography-ultraviolet detection-electrospray ion trap mass spectrometry. The Folin-Ciocalteau and the vanillin spectrophotometric assays were used for the assessment of the total polyphenol and total flavan-3-ol content, respectively, and the antioxidant activity was determined as the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and the ferricyanide reducing power. Catechin and prodelphinidin B3 were respectively the major monomeric and dimeric flavan-3-ols. Moreover, prodelphinidin B3 was shown to be the main contributor for the radical scavenging activity both for barley and malt.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Grão Comestível/química , Flavonoides/análise , Hordeum/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Antocianinas/análise , Antioxidantes/análise , Catequina/análise , Espectrofotometria Ultravioleta/métodos
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