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1.
Foods ; 13(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38611418

RESUMO

Coffee fruit cascara, which is the skin and pulp of the coffee cherry, has been authorized as a novel food for commercialization in the European Union. The present research assessed the feasibility of using spray drying to produce a soluble powder called instant cascara (IC), employing sun-dried ripe coffee cherry pulp as a raw material. Although there were no significant differences (p > 0.05) in the overall antioxidant capacity between the freeze-dried and spray-dried samples, after an in vitro simulation of the digestion process, the spray-dried sample was significantly (p < 0.05) more antioxidant. Both samples reduced physiological intracellular ROS and significantly decreased (p < 0.05) the secretion of the pro-inflammatory factor NO. Alkaloids and phenolic compounds were detected in intestinal digests. In conclusion, spray drying is a good technique for producing IC as its use does not affect its properties and causes less environmental impact than freeze drying, as calculated by life cycle assessment. Sensory analysis did not show significant differences between the commercial beverage and the IC beverage in the adult population. IC at 10 mg/mL was significantly less accepted in adolescents than the commercial beverage. Future work will include the reformulation of the IC beverage at 10 mg/mL, which has antioxidant and anti-inflammatory potential, to increase its hedonic acceptance in all consumer segments.

2.
Int J Mol Sci ; 25(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38612712

RESUMO

Tetraselmis chuii is an EFSA-approved novel food and dietary supplement with increasing use in nutraceutical production worldwide. This study investigated the neuroprotective potential of bioactive compounds extracted from T. chuii using green biobased solvents (ethyl acetate, AcOEt, and cyclopentyl methyl ether, CPME) under pressurized liquid extraction (PLE) conditions and supercritical fluid extraction (SFE). Response surface optimization was used to study the effect of temperature and solvent composition on the neuroprotective properties of the PLE extracts, including anticholinergic activity, reactive oxygen/nitrogen species (ROS/RNS) scavenging capacity, and anti-inflammatory activity. Optimized extraction conditions of 40 °C and 34.9% AcOEt in CPME resulted in extracts with high anticholinergic and ROS/RNS scavenging capacity, while operation at 180 °C and 54.1% AcOEt in CPME yielded extracts with potent anti-inflammatory properties using only 20 min. Chemical characterization revealed the presence of carotenoids (neoxanthin, violaxanthin, zeaxanthin, α- and ß-carotene) known for their anti-cholinesterase, antioxidant, and anti-inflammatory potential. The extracts also exhibited high levels of omega-3 polyunsaturated fatty acids (PUFAs) with a favorable ω-3/ω-6 ratio (>7), contributing to their neuroprotective and anti-inflammatory effects. Furthermore, the extracts were found to be safe to use, as cytotoxicity assays showed no observed toxicity in HK-2 and THP-1 cell lines at or below a concentration of 40 µg mL-1. These results highlight the neuroprotective potential of Tetraselmis chuii extracts, making them valuable in the field of nutraceutical production and emphasize the interest of studying new green solvents as alternatives to conventional toxic solvents.


Assuntos
Clorófitas , Ácidos Graxos Ômega-3 , Microalgas , Espécies Reativas de Oxigênio , Antagonistas Colinérgicos , Suplementos Nutricionais , Anti-Inflamatórios/farmacologia , Solventes
3.
Carbohydr Polym ; 326: 121578, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142064

RESUMO

This work evaluated the efficiency of Subcritical Water Extraction (SWE) and Pressurized Natural Deep Eutectic Solvents (P-NaDESs) under different temperatures (100, 120, 140 and 160 °C) in obtaining pectin from Passion Fruit Rinds (PFR) and its residual biomass (PFR - UAPLE), and compare the results with those of Conventional Extraction (CE). The highest pectin yields, 19.1 and 27.6 %, were achieved using P-NaDES (Citric Acid:Glucose:Water) at 120 °C for PFR and its PFR-UAPLE, respectively. Regarding the Degree of Esterification (DE), pectin obtained with SWE and CE had DE below 50 %, while with P-NaDES (Citric Acid: Glucose:Water), DE was above 50 %. Higher Molecular Weights (MW) (98 and 81 kDa) were obtained with SWE and P-NaDES from PFR compared to PFR-UAPLE and CE. Galacturonic acid was the most abundant (74 to 78 %) monosaccharide obtained by SWE. In terms of morphology, water extraction provided pectin with more uniform textures, whereas extraction with acidified mixtures led to more heterogeneous surfaces. Overall, comparing SWE and P-NaDES, the obtained pectins differed in terms of monomeric composition, MW and DE. These results indicate that pectins obtained by both methods can have different applications depending on their structural characteristics.


Assuntos
Passiflora , Pectinas , Pectinas/química , Água/química , Solventes Eutéticos Profundos , Passiflora/química , Frutas/química , Glucose/análise , Ácido Cítrico , Solventes
4.
Front Nutr ; 9: 953169, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36159477

RESUMO

Soybeans are mainly used for food and biodiesel production. It is estimated that soy crops worldwide will leave about 651 million metric tons of branches, leaves, pods, and roots on the ground post-harvesting in 2022/23. These by-products might serve as largely available and cheap source of high added-value metabolites, such as flavonoids, isoflavonoids, and other phenolic compounds. This work aimed to explore green approaches based on the use of pressurized and gas expanded-liquid extraction combined with natural deep eutectic solvents (NADESs) to achieve phenolic-rich extracts from soy by-products. The total phenolic and flavonoid contents of the generated extracts were quantified and compared with conventional solvents and techniques. Pressurized liquid extraction (PLE) with choline chloride/citric acid/water (1:1:11 - molar ratio) at 120°C, 100 bar, and 20 min, resulted in an optimized condition to generate phenolic and flavonoid-rich fractions of soy by-products. The individual parts of soy were extracted under these conditions, with their metabolic profile obtained by UHPLC-ESI-QToF-MS/MS and potential antioxidant properties by ROS scavenging capacity. Extracts of soy roots presented the highest antioxidant capacity (207.48 ± 40.23 mg AA/g), three times higher than soybean extracts (68.96 ± 12.30). Furthermore, Hansen solubility parameters (HSPs) were applied to select natural hydrophobic deep eutectic solvents (NaHDES) as substituents for n-heptane to defat soybeans. Extractions applying NaHDES candidates achieved a similar yield and chromatography profile (GC-QToF-MS) to n-heptane extracts.

5.
Food Chem X ; 13: 100242, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35498984

RESUMO

Pressurized liquid extraction (PLE) conditions were optimized to improve the recovery of orange (Citrus sinensis) by-products terpenoids. The neuroprotective potential of the PLE extracts were tested against a set of in-vitro assay (antioxidant (ABTS), reactive oxygen/nitrogen species (ROS/RNS)) as well as enzymatic tests (acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and lipoxygenase (LOX)). Gas chromatography coupled to high-resolution mass spectrometry (GC-q-TOF-MS) analysis revealed a higher enrichment in mono- and sesquiterpenoids of the PLE extracts with the highest neuroprotection capacity. In-silico molecular docking analysis showed the specific interaction of representative terpenoids with enzymes active sites. The results demonstrate that the selected extract at 100 °C and 30 minutes possesses high antioxidant (ABTSIC50 = 13.5 µg mL-1; ROSIC50 = 4.4 µg mL-1), anti-cholinesterase (AChEIC50 = 137.1 vg  L-1; BChEIC50 = 147.0 µg mL-1) and anti-inflammatory properties (against IL-6 and LOXIC50 = 76.1 µg mL-1), with low cytotoxicity and protection against L-glutamic acid in cell models.

6.
J Chromatogr A ; 1675: 463147, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35640448

RESUMO

This work reports the application of Gas Expanded Liquid (GXL) extraction to concentrate the flavonolignan fraction (silymarin) and taxifolin from Silybum marianum seeds, which have proven to be highly valuable health-promoting compounds. GXL using green solvents was used to isolate silymarin with the objective of replacing conventional methods. In one hand, the effect of different compositions of solvents, aqueous ethanol (20%, 50% or 80% (v/v)) at different CO2/liquid (25, 50 and 75%) ratios, on the GXL extraction was investigated. The obtained extracts have been chemically and functionally characterized by means of UHPLC-ESI-MS/MS (triple quadrupole) and in-vitro assays such as anti-inflammatory, anti-cholinergic and antioxidant. Results revealed that the operating conditions influenced the extraction yield, the total phenolic content and the presence of the target compounds. The best obtained yield was 55.97% using a ternary mixture of solvents composed of CO2:EtOH:H2O (25:60:15) at 40 °C and 9 MPa in 160 min. Furthermore, the results showed that obtained extracts had significant antioxidant and anti-inflammatory activities (with best IC50 value of 8.80 µg/mL and 28.52 µg/mL, respectively) but a moderate anti-cholinesterase activity (with best IC50 value of 125.09 µg/mL). Otherwise, the concentration of silymarin compounds in extract can go up to 59.6% using the present one-step extraction method without further purification, being silybinA+B the predominant identified compound, achieving value of 545.73 (mg silymarin/g of extract). The obtained results demonstrate the exceptional potential of GXL to extract high-added values molecules under sustainable conditions from different matrices.


Assuntos
Silybum marianum , Silimarina , Argélia , Antioxidantes/análise , Dióxido de Carbono/análise , Cromatografia Líquida de Alta Pressão/métodos , Etanol/análise , Flavonoides/análise , Silybum marianum/química , Extratos Vegetais/química , Sementes/química , Solventes/química , Espectrometria de Massas em Tandem
7.
J Chromatogr A ; 1669: 462922, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35287030

RESUMO

In this work, the application of betaine-based hydrophilic natural deep eutectic solvents (NADESs) as green extraction solvents was proposed for the first time for the evaluation of twelve pesticides in citrus and olive by-products intended to be applied as potential sources of compounds with neuroprotective activity against Alzheimer Disease. Ultrasound-assisted extraction of selected pesticides was followed by separation and determination using gas chromatography coupled to single quadrupole mass spectrometry. Eight NADESs were tested using different hydrogen bond donors (i.e. citric and lactic acid, fructose, glucose, glycerol, propylene glycol, propionic and butanoic acid). Other factors affecting extraction efficiency were also evaluated using a step-by-step approach. Eight mL of a mixture composed of 60% betaine:propylene glycol NADES at a molar ratio 1:4 and 40% of water, as well as 30 min of ultrasound-assisted extraction were selected as the most adequate conditions. The methodology was validated prior to its application in citrus and olive by-products. Recovery values were between 73 and 115% (RSD% < 20%), while limits of quantification of the method were in the range 8.5-128.8 µg/kg, which demonstrates the suitability of the procedure to determine the selected group of pesticides, usually applied in citrus and olive crops, at the legislated levels. The greenness of the procedure was also evaluated using AGREE calculator. Finally, the whole method was applied for the safety assessment of seven olive leaf samples and seven citrus by-products produced in Spain, finding the presence of several of the evaluated compounds at concentrations higher than the established limits for similar products.


Assuntos
Citrus , Olea , Solventes Eutéticos Profundos , Cromatografia Gasosa-Espectrometria de Massas , Solventes/química
8.
Molecules ; 26(22)2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34834042

RESUMO

Ammodaucus leucotrichus is a spontaneous plant endemic of the North African region. An efficient selective pressurized liquid extraction (PLE) method was optimized to concentrate neuroprotective extracts from A. leucotrichus fruits. Green solvents were tested, namely ethanol and water, within a range of temperatures between 40 to 180 °C. Total carbohydrates and total phenolics were measured in extracts, as well as in vitro antioxidant capacity (DPPH radical scavenging), anticholinesterase (AChE) and anti-inflammatory (LOX) activities. Metabolite profiling was carried out by ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight tandem mass spectrometry (UHPLC-ESI-q-TOF-MS/MS), identifying 94 compounds. Multivariate analysis was performed to correlate composition with bioactivity. A remarkable effect of the temperature using water was observed: the higher temperature, the higher extraction yield, the higher total phenolic content, as well as the higher total carbohydrates content. The water extract obtained at 180 °C, 10.34 MPa and 10 min showed meaningful anti-inflammatory (IC50LOX = 39.4 µg/mL) and neuroprotective activities (IC50AChE = 55.6 µg/mL). The Principal Components Analysis (PCA) and the cluster analysis correlated these activities with the presence of carbohydrates and phenolic compounds.


Assuntos
Apiaceae/química , Metabolômica , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , Avaliação de Medicamentos , Espectrometria de Massas em Tandem
9.
Foods ; 10(6)2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34198926

RESUMO

This work reports the use of GC-QTOF-MS to obtain a deep characterization of terpenoid compounds recovered from olive leaves, which is one of the largest by-products generated by the olive oil industry. This work includes an innovative supercritical CO2 fractionation process based on the online coupling of supercritical fluid extraction (SFE) and dynamic adsorption/desorption for the selective enrichment of terpenoids in the different olive leaves extracts. The selectivity of different commercial adsorbents such as silica gel, zeolite, and aluminum oxide was evaluated toward the different terpene families present in olive leaves. Operating at 30 MPa and 60 °C, an adsorbent-assisted fractionation was carried out every 20 min for a total time of 120 min. For the first time, GC-QTOF-MS allowed the identification of 40 terpenoids in olive leaves. The GC-QTOF-MS results indicate that silica gel is a suitable adsorbent to partially retain polyunsaturated C10 and C15 terpenes. In addition, aluminum oxide increases C20 recoveries, whereas crystalline zeolites favor C30 terpenes recoveries. The different healthy properties that have been described for terpenoids makes the current SFE-GC-QTOF-MS process especially interesting and suitable for their revalorization.

10.
Trends Analyt Chem ; 129: 115942, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32834241

RESUMO

Many natural compounds, found mainly in plants, are associated with the treatment of various diseases. The search for natural therapeutic agents includes compounds with antiviral and anti-inflammatory activities. Among the many steps involved in bioprospection, extraction is the first and most critical step for obtaining bioactive compounds. One of the main advantages of using compressed fluids extraction is the high quality of the final product obtained due to the use of green solvents, while the selectivity towards target compounds can be tuned by adjusting the process parameters, especially pressure, temperature and solvent characteristics. In this review, a discussion is provided on the power of compressed fluids, such as supercritical fluid extraction (SFE), pressurized liquid extraction (PLE) and subcritical water extraction (SWE) to obtain antiviral and anti-inflammatory compounds from natural sources. In addition, an adequate knowledge about the identity and quantity of the compounds present in the extract is essential to correlate biological activity with chemical composition. Phytochemical profiling tools used for identification and quantification of these bioactive natural compound are also discussed. It can be anticipated that after the current SARS-COV-2 pandemic, the search of new natural compounds with antiviral and anti-inflammatory activity will be a hot research topic, so, this review provides an overview on the technologies currently used that could help this research.

11.
Mar Drugs ; 18(6)2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32545497

RESUMO

In the present study, the chemical composition of the microalga Euglena cantabrica was investigated. The extraction of bioactive compounds was done using pressurized liquid extraction (PLE) at different temperatures (40-180 °C) and using green solvents (ethanol-water mixtures). A statistical design of experiments was used to optimize the maximum antioxidant capacity of the extracts by response surface methodology. The antioxidant capacity was determined through the inhibition of 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, while the chemical analyses of the extracts were carried out using different chromatographic techniques. Chlorophylls and carotenoids were analyzed by high-performance liquid chromatography coupled to a diode array detector and mass spectrometry (HPLC-DAD-MS/MS) and carbohydrates by gas chromatography with flame ionization detection (GC-FID) and high-pressure size-exclusion chromatography coupled to an evaporative light-scattering detector (HPSEC-ELSD). The results showed different possibilities for the extraction conditions, depending on the desired bioactivity or chemical composition. Briefly, (i) mixtures of ethanol-water containing around 40% ethanol at 180 °C gave the best antioxidant capacity, (ii) mixtures containing around 50% ethanol at 110 °C gave the best yield of ß-glucan paramylon, and (iii) the use of pure ethanol at a low temperature (40 °C) is the best choice for the recovery of carotenoids such as diatoxanthin. Summing up, E. cantabrica seems to be a good candidate to be used in biorefinery to obtain different bioactive compounds.


Assuntos
Euglena/química , Extratos Vegetais/química , Animais , Solventes , Temperatura
12.
Foods ; 9(5)2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32408584

RESUMO

Our research aimed to evaluate the formation of Maillard reaction products in sun-dried coffee cascara and their impact on the safety and health promoting properties of a novel beverage called "Instant Cascara" (IC) derived from this coffee by-product. Maillard reaction products in sun-dried coffee cascara have never been reported. "Instant Cascara" (IC) extract was obtained by aqueous extraction and freeze-drying. Proteins, amino acids, lipids, fatty acid profile, sugars, fiber, minerals, and vitamins were analyzed for its nutritional characterization. Acrylamide and caffeine were used as chemical indicators of safety. Colored compounds, also called melanoidins, their stability under 40 °C and in light, and their in vitro antioxidant capacity were also studied. A safe instant beverage with antioxidant properties was obtained to which the following nutritional claims can be assigned: "low fat", "low sugar" "high fiber" and "source of potassium, magnesium and vitamin C". For the first time, cascara beverage color was attributed to the presence of antioxidant melanoidins (>10 kDa). IC is a potential sustainable alternative for instant coffee, with low caffeine and acrylamide levels and a healthy composition of nutrients and antioxidants.

13.
Carbohydr Polym ; 217: 69-78, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079687

RESUMO

Pectin was obtained with citric acid and subcritical water extraction from cacao pod husk with or without a previous step consisting of a supercritical fluid extraction of phenols. By subcritical conditions a higher yield (10.9%) was attained in a time 3-fold shorter than that obtained by conventional extraction (˜8%) and a greater effectiveness in the recovery of pectin with higher molecular weight (750 kDa) was also found. Regarding pectin structure, galacturonic acid and degree of methyl esterification content were similar (˜55 and ˜36%, respectively) in both methods. Moreover, pectin recovered by citric acid presented 2-fold higher amount of impurities as compared to subcritical water extraction. Hardly any effects of a previous supercritical treatment were observed in the structure and composition of pectin, indicating the efficiency of the integrated supercritical carbon dioxide and subcritical water extraction as green processes for the obtainment of phenol and pectin from cacao pod husk.


Assuntos
Cacau/química , Pectinas/química , Química Verde/métodos , Resíduos Industriais , Peso Molecular , Pectinas/isolamento & purificação , Extração em Fase Sólida/métodos , Resíduos Sólidos , Água/química
14.
Int J Mol Sci ; 15(9): 16270-83, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25226536

RESUMO

The potential of by-products generated during extra-virgin olive oil (EVOO) filtration as a natural source of phenolic compounds (with demonstrated bioactivity) has been evaluated using pressurized liquid extraction (PLE) and considering mixtures of two GRAS (generally recognized as safe) solvents (ethanol and water) at temperatures ranging from 40 to 175 °C. The extracts were characterized by high-performance liquid chromatography (HPLC) coupled to diode array detection (DAD) and electrospray time-of-flight mass spectrometry (HPLC-DAD-ESI-TOF/MS) to determine the phenolic-composition of the filter cake. The best isolation procedure to extract the phenolic fraction from the filter cake was accomplished using ethanol and water (50:50, v/v) at 120 °C. The main phenolic compounds identified in the samples were characterized as phenolic alcohols or derivatives (hydroxytyrosol and its oxidation product), secoiridoids (decarboxymethylated and hydroxylated forms of oleuropein and ligstroside aglycones), flavones (luteolin and apigenin) and elenolic acid derivatives. The PLE extraction process can be applied to produce enriched extracts with applications as bioactive food ingredients, as well as nutraceuticals.


Assuntos
Óleos de Plantas/química , Cromatografia Líquida de Alta Pressão , Etanol/química , Extração Líquido-Líquido , Azeite de Oliva , Fenóis/análise , Óleos de Plantas/análise , Pressão , Solventes/química , Espectrometria de Massas por Ionização por Electrospray , Água/química
15.
Talanta ; 104: 44-52, 2013 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-23597887

RESUMO

A comparative study between "alternative" extraction processes such as centrifugal partition extraction (CPE), supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE) and classical solid/liquid used in the laboratory are currently focusing on the efficiency (selectivity and productivity) to obtain bioactive phenolic compounds from the phaeophyte Sargassum muticum model. The choice of the best process was based on several measurements: (i) the total phenolic content measured by the colorimetric Folin-Ciocalteu assay, (ii) radical scavenger and antioxidant activities assessed by the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay, and the ß-carotene bleaching method and finally (iii) the method productivity. Irrespective of the solvent used in the processes, alternative methods are always sharply more effective than classical ones. With the exception of SFE which does not allow extracting the totality of the active phenolic compounds, two of the other extraction methods were particularly promising. First, CPE afforded the most important yields in concentrated phenolic compounds (PC) (22.90±0.65% DW) also displaying the best activities (0.52±0.02 and 0.58±0.19 mg/mL for IC50 and AAC700, respectively). Secondly, PLE using an EtOH:water mixture 75:25 (v/v) allowed a good PC extraction (10.18±0.25% DW) with huge efficiency. Despite a lesser activity of the extracts (0.77±0.01 and 1.59±0.15 mg/mL for IC50 and AAC700, respectively) PLE is a green process and potentially complies European norms requirements for the prospective valorization of phenolic compounds from S. muticum in Brittany.


Assuntos
Antioxidantes/isolamento & purificação , Fenóis/isolamento & purificação , Sargassum/química , Antioxidantes/química , Compostos de Bifenilo/química , Química Verde , Espectroscopia de Ressonância Magnética , Fenóis/química , Picratos/química , Extratos Vegetais/análise , Extratos Vegetais/química , beta Caroteno/química
16.
Anal Bioanal Chem ; 405(13): 4607-16, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23314588

RESUMO

A novel experimental design was used to optimize the extraction of carotenoids from Neochloris oleoabundans using pressurized liquid extraction with food-grade solvents such as ethanol and limonene. Experimental factors, including the extraction temperature and the solvent composition, were optimized using a three-level factorial design. The response variables extraction yield and total amount of carotenoids were assessed. The statistical analysis of the results provided mathematical models to predict the behavior of the responses as a function of the factors involved in the process. The optimum conditions predicted by the model developed in this study were 112 °C as the extraction temperature and 100% ethanol as the extraction solvent. Chemical characterization of the extracts obtained was performed by means of high-performance liquid chromatography-tandem mass spectrometry. The results obtained demonstrated that, under certain growth conditions (photoautotrophically cultured in a medium supplemented with 0.3 g L(-1) KNO3), N. oleoabundans accumulated significant total amounts of the carotenoids (from 57.4 to 120.2 mg carotenoids per gram of extract depending on the extraction conditions), mainly lutein, cantaxanthin, zeaxanthin, and astaxanthin monoesters and diesters.


Assuntos
Carotenoides/isolamento & purificação , Clorófitas/química , Extração Líquido-Líquido/métodos , Microalgas/química , Algoritmos , Carotenoides/classificação , Cromatografia Líquida , Cicloexenos , Etanol , Limoneno , Extração Líquido-Líquido/normas , Pressão , Solventes , Espectrometria de Massas em Tandem , Temperatura , Terpenos
17.
J Agric Food Chem ; 58(6): 3772-8, 2010 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-20170168

RESUMO

A procedure based on the application of supercritical CO(2) extraction to reduce and/or to remove odorant volatile compounds from a winemaking inactive dry yeast (IDY) preparation has been set up. By applying a factorial design, a screening of different temperatures and pressure conditions was assayed in order to determine the optimal deodorization conditions, and afterward the effect of several sample pretreatments was investigated. The best extraction conditions were achieved at 200 atm and 60 degrees C, applying the cryogenic grinding of the sample and using 40% (w/w) ethanol as cosolvent. By using these conditions, it was possible to reduce to approximately 70% of the volatile compounds present in the samples that may be released into the wines and therefore affecting their sensory characteristics. Odorant volatile compounds such as 2-methylhydroxypyrrole, 2-ethyl-6-methylpyrazine, and 2,3,5-trimethylpyrazine completely disappeared from the deodorized sample as verified by GC-O analysis. Additional experiments in model wines confirmed the low release of volatile compounds from the deodorized samples, without provoking any change to their nonvolatile composition (nitrogen compounds and neutral polysaccharides) that is related to the technological properties of these preparations.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Manipulação de Alimentos/métodos , Odorantes/prevenção & controle , Saccharomyces cerevisiae/metabolismo , Compostos Orgânicos Voláteis/isolamento & purificação , Vinho/análise , Fermentação , Odorantes/análise , Controle de Qualidade , Compostos Orgânicos Voláteis/análise , Vinho/parasitologia
18.
J Chromatogr A ; 1217(16): 2495-511, 2010 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-20022016

RESUMO

Among the different extraction techniques used at analytical and preparative scale, supercritical fluid extraction (SFE) is one of the most used. This review covers the most recent developments of SFE in different fields, such as food science, natural products, by-product recovery, pharmaceutical and environmental sciences, during the period 2007-2009. The revision is focused on the most recent advances and applications in the different areas; among them, it is remarkable the strong impact of SFE to extract high value compounds from food and natural products but also its increasing importance in areas such as heavy metals recovery, enantiomeric resolution or drug delivery systems.


Assuntos
Fracionamento Químico/métodos , Produtos Biológicos/química , Poluentes Ambientais/química , Análise de Alimentos , Metais Pesados/química , Preparações Farmacêuticas/química
19.
J Agric Food Chem ; 58(2): 787-92, 2010 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-20025217

RESUMO

In the present work, an environmentally friendly extraction process using subcritical conditions has been tested to obtain potential natural food ingredients from natural sources such as plants, fruits, spirulina, propolis, and tuber, with the scope of substituting synthetic antioxidants, which are subject to regulation restrictions and might be harmful for human health. A full characterization has been undertaken from the chemical and biochemical point of view to be able to understand their mechanism of action. Thus, an analytical method for profiling the compounds responsible for the antioxidant activity has been used, allowing the simultaneous determination of water-soluble vitamins, fat-soluble vitamins, phenolic compounds, carotenoids, and chlorophylls in a single run. This information has been integrated and analyzed using a chemometrical approach to correlate the bioactive compounds profile with the antioxidant activity and thus to be able to predict antioxidant activities of complex formulations. As a further step, a simplex centroid mixture design has been tested to find the optimal formulation and to calculate the effect of the interaction among individual extracts in the mixture.


Assuntos
Antioxidantes/química , Produtos Biológicos/química , Aditivos Alimentares/química , Plantas/química , Spirulina/química , Carotenoides/análise , Fenóis/análise , Extratos Vegetais/química , Vitaminas/análise
20.
J Food Prot ; 71(10): 2138-43, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18939768

RESUMO

The objective of this research was to evaluate the antimicrobial activity of carbon dioxide extracts of the unicellular biflagellated green alga Dunaliella salina against Escherichia coli, Staphylococcus aureus, Candida albicans, and Aspergillus niger. The effects of different extraction pressures ranging from 185 to 442 bar and extraction temperatures ranging from 9.8 to 45.2 degrees C on the extracts' composition and consequently on their antimicrobial activities were investigated. The extracts were analyzed by gas chromatography-mass spectrometry in order to identify the compounds responsible for the antimicrobial activity detected. Fourteen different volatile compounds and several fatty acids were identified. The highest antimicrobial activity was obtained using 314 bar and 9.8 degrees C. Under these conditions, the presence of an indolic derivative that had never been reported in D. salina was detected in the extract, together with polyunsaturated fatty acids and compounds related to carotene metabolism, such as beta-ionone and neophytadiene, with known antimicrobial activity.


Assuntos
Antibacterianos/farmacologia , Dióxido de Carbono/farmacologia , Clorófitas/química , Conservação de Alimentos/métodos , Extratos Vegetais/farmacologia , Antibacterianos/análise , Aspergillus niger/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Alimentos Orgânicos , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Óleos Voláteis/análise , Óleos Voláteis/farmacologia , Extratos Vegetais/análise , Staphylococcus aureus/efeitos dos fármacos
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