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1.
J Oleo Sci ; 71(1): 51-55, 2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-34880149

RESUMO

Vitamin E (VitE) production from crude palm oil (CPO) has been extensively studied and industrially conducted. VitE in CPO is in the range of 600 to 1,000 ppm, and is usually produced from one of the main by-products of edible palm oil production, namely palm fatty acid distillate (PFAD). PFAD contains 4,000 to 5,500 ppm of VitE, and is produced from deodorization process of palm oil purification. This paper presents an innovative process of VitE concentrate production from CPO. A scrubber was designed and installed between the deodorizer and conventional PFAD scrubber. The main objective of this new scrubber was a recovery of glycerides from PFAD. This new scrubber is operated at 150 to 160℃. The scrubbed oil is named as Scrubbed Palm Fatty Acid Distillate (S-PFAD). This simple and efficient modified process can retrieve glycerides as S-PFAD at 0.3% recovery and it enhances VitE concentration in S-PFAD to the range of 28,000 to 32,000 ppm, which is the highest concentration of VitE that has ever been produced in the palm oil production. Fatty acids and glycerides in S-PFAD were esterified and transesterified to methyl esters. The methyl esters were evaporated from S-PFAD, and S-PFAD residue oil contained 24.7% VitE.


Assuntos
Manipulação de Alimentos/métodos , Óleo de Palmeira/química , Vitamina E/isolamento & purificação , Esterificação , Ésteres/química , Glicerídeos/isolamento & purificação , Temperatura Alta , Óleo de Palmeira/análise , Vitamina E/análise
2.
Nutrients ; 13(7)2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34371875

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) have been recognized to cause neurobehavioral dysfunctions and disorder of cognition and behavioral patterns in childhood. Momordica charantia L. (MC) has been widely known for its nutraceutical and health-promoting properties. To date, the effect of MC for the prevention and handling of PAHs-induced neurotoxicity has not been reported. In the current study, the neuroprotective effects of MC and its underlying mechanisms were investigated in mouse hippocampal neuronal cell line (HT22); moreover, in silico analysis was performed with the phytochemicals MC to decipher their potential function as neuroprotectants. MC was demonstrated to possess neuroprotective effect by reducing reactive oxygen species' (ROS') production and down-regulating cyclin D1, p53, and p38 mitogen-activated protein kinase (MAPK) protein expressions, resulting in the inhibition of cell apoptosis and the normalization of cell cycle progression. Additionally, 28 phytochemicals of MC and their competence on inhibiting cytochrome P450 (CYP: CYP1A1, CYP1A2, and CYP1B1) functions were resolved. In silico analysis of vitamin E and stigmasterol revealed that their binding to either CYP1A1 or CYP1A2 was more efficient than the binding of each positive control (alizarin or purpurin). Together, MC is potentially an interesting neuroprotectant including vitamin E and stigmasterol as probable active components for the prevention for PAHs-induced neurotoxicity.


Assuntos
Hipocampo/efeitos dos fármacos , Momordica charantia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Estigmasterol/farmacologia , Vitamina E/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Camundongos , Momordica charantia/química , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo , Estigmasterol/isolamento & purificação , Vitamina E/isolamento & purificação
3.
J Sci Food Agric ; 101(1): 101-109, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32613642

RESUMO

BACKGROUND: Phytosterols are plant components with health benefits. Oleaginous seed hybridization can be relevant to increase phytosterols in diet through enriched oils. Sunflower oils obtained by press (PO) and subsequent solvent extraction (SO) from three types of phytosterol-enriched seeds were characterized. One presented a phytosterol composition of common sunflower seeds, whereas the other two were rich in campesterol and Δ7-stigmasterol, respectively. Seeds from two different harvests, 2015 and 2017, were studied. RESULTS: The type of extraction did not have a significant influence on the fatty acid composition. However, considerable differences were found between harvests. The oleic-to-linoleic ratio decreased from 0.71 in 2015 to 0.47 in 2017. The phytosterol compositions of the PO were similar to their SO homologues and no substantial differences were found between harvests. However, the SO presented higher total contents of phytosterols (4849-9249 mg kg-1 ) than the PO (2839-5284 mg kg-1 ) and the oils of 2017 showed higher levels (4476-9249 mg kg-1 ) compared to 2015 (2839-5754 mg kg-1 ). Unlike phytosterols, no significant differences were found in the tocopherol contents between the PO and SO or between harvests. The PO met Codex specifications for edible oils, except for trace metals, with concentrations close or above the limits for Cu, Fe, Pb and As. CONCLUSIONS: Differences in environmental and/or cultivation conditions between harvests may result in substantial differences in the fatty acid composition and phytosterol content in oils from the new sunflower seeds. Rigorous measures and controls to avoid trace metal contamination are required so that the PO can be considered as edible virgin oils. © 2020 Society of Chemical Industry.


Assuntos
Fracionamento Químico/métodos , Manipulação de Alimentos/métodos , Helianthus/química , Fitosteróis/química , Óleo de Girassol/química , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Fitosteróis/isolamento & purificação , Sementes/química , Vitamina E/análise , Vitamina E/isolamento & purificação
4.
Anal Sci ; 36(9): 1091-1097, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32336730

RESUMO

Roselle seeds, a waste biomass of the roselle calyx processing industry, were utilized to recover valuable compounds of oil, vitamin E, and water-soluble saccharides. Firstly, ultrasound-assisted extraction (UAE) and conventional stirring extraction were conducted for saccharide extraction, and the advantage of UAE was confirmed. Secondly, oil, vitamin E, and saccharides extracted from Vietnamese roselle seeds by UAE were analyzed for the first time. Oil of tri-, di-, and mono-glycerides, fatty acids of linoleic-, oleic-, palmitic-, and stearic-acids, vitamin E of γ- and α-tocopherol, and saccharides of sucrose, raffinose, stachyose, etc. were identified, and the amounts of these components were compared with those in other country's roselle seeds. Thirdly, cascade extraction of oil, vitamin E, and saccharides by UAE was investigated with solvents of hexane, hexane:ethyl acetate binary solvent, and water. The results indicated that the order of using solvents was very important for high and selective extraction: the best order to recover oil (almost 100%), vitamin E (95.7%), and saccharides (86.2%) was hexane, and then water.


Assuntos
Carboidratos/isolamento & purificação , Fracionamento Químico/métodos , Hibiscus/química , Óleos de Plantas/isolamento & purificação , Sementes/química , Ondas Ultrassônicas , Vitamina E/isolamento & purificação , Carboidratos/química , Hexanos/química , Óleos de Plantas/química , Solventes/química , Vitamina E/química
5.
Biomed Res Int ; 2019: 4503450, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30881987

RESUMO

The objective of this study was to evaluate the association between salivary 1,5-anhydroglucitol (AG), vitamins A (VA), C (VC), and E (VE), and caries risk in children. 100 healthy children aged between 6 and 13 years were divided into two equal groups of caries-free (DMFS/dmfs=0) and caries active (DMFS/dmfs>3). Unstimulated midmorning saliva was collected from all the children and the levels of salivary AG and vitamins A, C, and E were measured. Caries risk assessment was done using American Academy of Pediatric Dentistry Caries Assessment Tool. Analysis of salivary AG and vitamins was performed using a commercially available ELISA kit. Low levels of AG were present in caries active and high caries risk groups compared to caries-free and low/medium caries risk groups. This difference is statistically significant (p < 0.05). A strong negative correlation between AG and caries activity was observed in the caries active group. VA was not related to caries activity, while VC and VE displayed a statistically significant correlation (p < 0.05). Similarly, a strong negative correlation was observed between the levels of AG and high caries risk group. Salivary AG, VC, and VE together are related to caries risk in caries active children. These salivary parameters can act as indicator of caries status in children.


Assuntos
Ácido Ascórbico/metabolismo , Cárie Dentária/metabolismo , Vitamina A/metabolismo , Vitamina E/metabolismo , Adolescente , Ácido Ascórbico/isolamento & purificação , Criança , Cárie Dentária/epidemiologia , Cárie Dentária/patologia , Desoxiglucose/isolamento & purificação , Desoxiglucose/metabolismo , Feminino , Humanos , Masculino , Fatores de Risco , Saliva/química , Saliva/metabolismo , Vitamina A/isolamento & purificação , Vitamina E/isolamento & purificação
6.
J Food Drug Anal ; 27(1): 71-82, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30648596

RESUMO

Rice bran oil (RBO) has become a popular oil globally. However, the RBO extraction process leaves various residue products, which contain bioactive substances of varying potency which could be significant sources of functional ingredients for both food production and pharmaceutical manufacture. The objective of our study was to compare the bioactive substances in various by-products derived from the two rice bran oil processing methods; solvent extraction and cold pressing. The residues from solvent extraction processing contained up to 97.37 mg/100 g of γ-aminobutyric acid in defatted rice bran, and the rice acid oil contained high levels of vitamin E (tocopherols, tocotrienols), up to 120.59 mg/100 g, as well as γ-oryzanol (3829.65 mg/100 g), phytosterol (599.40 mg/100 g), and policosanol compounds (332.79 mg/100 g). All of these values are higher than in the residues derived from cold pressing. Importantly, high amounts of total nutraceuticals (8.3 kg/100 kg) were found in residues from both processing methods, indicating the commercial potential of these residues as a source of functional ingredients for food production, as dietary supplements, and in pharmaceutical manufacture.


Assuntos
Fracionamento Químico/métodos , Suplementos Nutricionais/análise , Manipulação de Alimentos/métodos , Oryza/química , Óleo de Farelo de Arroz/análise , Óleo de Farelo de Arroz/isolamento & purificação , Resíduos/análise , Fenilpropionatos/análise , Fenilpropionatos/isolamento & purificação , Sementes/química , Vitamina E/análise , Vitamina E/isolamento & purificação
7.
Food Chem ; 256: 327-332, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29606456

RESUMO

A new vitamin E homologue, α-tocomonoenol was detected in palm oil, but was not isolated in large amounts and with high purity so far. Here we present an easy and fast method to isolate α-tocomonoenol from vitamin E rich nutrient capsules with countercurrent chromatography (CCC). With the solvent system n-hexane - benzotrifluoride - acetonitrile (10:3.5:6.5, v/v/v) about 30 mg α-tocomonoenol with a purity of 75% could be enriched in one step from 1 g crude sample. Column chromatography with 20% deactivated silica gel and n-hexane - ethyl acetate (95:5, v/v) was performed to gain 5.6 mg α-tocomonoenol with a purity of 99.5% according to GC/MS. Structural verification by 1H NMR spectroscopy verified that the double bond was located in 11'-position (11'-α-tocomonoenol). The trace impurity detected in the isolate was identified to be 12'-α-tocomonoenol, a compound previously detected in marine samples.


Assuntos
Óleo de Palmeira/química , Extratos Vegetais/isolamento & purificação , Vitamina E/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Distribuição Contracorrente/métodos , Cromatografia Gasosa-Espectrometria de Massas , Extratos Vegetais/química , Vitamina E/química , Vitamina E/isolamento & purificação
8.
Nat Prod Res ; 32(10): 1130-1135, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28438040

RESUMO

In this work, we report a rapid and convenient HPLC-UV-DAD method for the isolation of δ-T3 on semi-preparative scale from two different vitamin E rich processed, commercially available products obtained from the fruits of Elaeis guineensis Jacq. (oil palm) and from the seeds of Bixa orellana L. (achiote tree). Chromatography was run using reverse phase (RP) C-18 columns and HPLC-grade acetonitrile as mobile phase. The purity of the isolated δ-T3, assessed by GC-MS and 1H NMR was above 98%. The δ-T3 cytotoxic activity found in vitro against the proliferation of human A375 melanoma cells compared to that of the other δ-T3 free tocols mixture suggest its primary role in the experimental anticancer activity observed for palm oil derived products. Taken altogether, the results of this study highlight the importance of the application of suitable purification systems for the preparations of tocotrienols prior to their experimental or clinical testing.


Assuntos
Arecaceae/química , Bixaceae/química , Cromatografia Líquida de Alta Pressão/métodos , Vitamina E/análogos & derivados , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Frutas/química , Humanos , Melanoma/tratamento farmacológico , Sementes/química , Tocotrienóis/química , Vitamina E/isolamento & purificação , Vitamina E/farmacologia
9.
Molecules ; 22(9)2017 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-28850073

RESUMO

There are six tocol analogs present in palm oil, namely α-tocopherol (α-T), α-tocomonoenol (α-T1), α-tocotrienol (α-T3), γ-tocotrienol (γ-T3), ß-tocotrioenol (ß-T3) and δ-tocotrienol (δ-T3). These analogs were difficult to separate chromatographically due to their similar structures, physical and chemical properties. This paper reports on the effect of pressure and injection solvent on the separation of the tocol analogs in palm oil. Supercritical CO2 modified with ethanol was used as the mobile phase. Both total elution time and resolution of the tocol analogs decreased with increased pressure. Ethanol as an injection solvent resulted in peak broadening of the analogs within the entire pressure range studied. Solvents with an eluent strength of 3.4 or less were more suitable for use as injecting solvents.


Assuntos
Óleo de Palmeira/química , Tocoferóis/química , Tocoferóis/isolamento & purificação , Cromanos/química , Cromanos/isolamento & purificação , Cromatografia com Fluido Supercrítico/métodos , Estrutura Molecular , Pressão , Solventes , Tocotrienóis/química , Tocotrienóis/isolamento & purificação , Vitamina E/análogos & derivados , Vitamina E/química , Vitamina E/isolamento & purificação , alfa-Tocoferol/química , alfa-Tocoferol/isolamento & purificação
10.
Molecules ; 22(2)2017 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-28165404

RESUMO

Vitamin E is recognized as an essential vitamin since its discovery in 1922. Most vegetable oils contain a mixture of tocopherols and tocotrienols in the vitamin E composition. Structurally, tocopherols and tocotrienols share a similar chromanol ring and a side chain at the C-2 position. Owing to the three chiral centers in tocopherols, they can appear as eight different stereoisomers. Plant sources of tocopherol are naturally occurring in the form of RRR while synthetic tocopherols are usually in the form of all-racemic mixture. Similarly, with only one chiral center, natural tocotrienols occur as the R-isoform. In this review, we aim to discuss a few chromatographic methods that had been used to separate the stereoisomers of tocopherols and tocotrienols. These methods include high performance liquid chromatography, gas chromatography and combination of both. The review will focus on method development including selection of chiral columns, detection method and choice of elution solvent in the context of separation efficiency, resolution and chiral purity. The applications for separation of enantiomers in vitamin E will also be discussed especially in terms of the distinctive biological potency among the stereoisoforms.


Assuntos
Cromatografia , Vitamina E/química , Vitamina E/isolamento & purificação , Cromatografia/métodos , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Estereoisomerismo , Tocoferóis/química , Tocotrienóis/química
11.
J Chromatogr Sci ; 55(2): 149-153, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28087759

RESUMO

The effect of π-electrons and hydroxyl group on the separations of vitamin E on a swelling-controlled polystyrene-divinylbenzene (Phenogel) column using toluene/isooctane as the mobile phase was investigated. The effect of the π-electrons was demonstrated in the baseline separation of α-tocopherol and α-tocotrienol on a 100-Å Phenogel column. In addition, baseline separation of α-, (ß- + Î³-)- and δ-tocopherol could be achieved on this column. The separation mechanism of these isomers are due to the difference in the interactions between the hydroxyl group on the chromanol ring of each tocopherol and the gel matrix caused by the steric hindrance of methyl group(s). It was concluded that solutes of the same molecular size but different in the polar groups could be separated on a high performance size-exclusion chromatography by controlling the swelling of the gel matrix via modification of the mobile phase.


Assuntos
Cromatografia em Gel/métodos , Cromatografia Líquida de Alta Pressão/métodos , Poliestirenos/química , Vitamina E/análise , Vitamina E/isolamento & purificação , Cromatografia em Gel/instrumentação , Cromatografia Líquida de Alta Pressão/instrumentação , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
12.
Food Funct ; 8(1): 201-208, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-27990543

RESUMO

Chestnuts are a common food product in Mediterranean countries, being recognized also for their beneficial effects on human health. Nevertheless, during processing, these fruits generate a large amount of food by-products, such as shells and burs. In the present work, the macronutrient composition, vitamin E profile and amino acid content of the burs were determined in samples from three different Portuguese regions (Minho, Trás-os-Montes and Beira-Alta). The nutritional composition was similar for all samples, being characterised by a high moisture content and low fat amounts. All essential amino acids were present in considerable amounts. Concerning vitamin E, the predominant vitamer was α-tocopherol for the Minho and Beira-Alta samples. The total phenolic compounds were quantified, and the antioxidant activity evaluated in different extracts using two biochemical assays (DPPH˙ and FRAP). All bur extracts showed a high total phenolic content, the highest obtained being that for the Beira-Alta samples. The chestnut bur from Minho showed the highest antioxidant activity in both assays. This study aims to demonstrate the potential of the Castanea sativa bur as a cosmetic and nutraceutical ingredient.


Assuntos
Cosméticos/análise , Suplementos Nutricionais/análise , Fagaceae/química , Extratos Vegetais/análise , Resíduos/análise , Aminoácidos/análise , Aminoácidos/isolamento & purificação , Frutas/química , Fenóis/análise , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Vitamina E/análise , Vitamina E/isolamento & purificação
13.
Food Chem ; 217: 106-111, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27664614

RESUMO

This study was performed to investigate changes in the phenolic acid and vitamin E profiles of germinated rough rice following high hydrostatic pressure treatment (HPT). Rough rice was germinated at 37°C for two days and subjected to 0.1, 10, 30, 50, and 100MPa pressures for 24h. The total phenolic acid content increased from 85.37µg/g at 0.1MPa to 183.52µg/g at 100MPa. The highest gallic acid (4.29µg/g), catechin (9.55µg/g), p-coumaric acid (8.36µg/g), ferulic acid (14.99µg/g), salicylic acid (14.88µg/g), naringin (6.18µg/g), trans-cinnamic acid (45.23µg/g), and kaempferol (40.95µg/g) contents occurred in the sample treated at 100MPa after germination. The maximum vitamin E content of about 2.56 (BG) and 4.34mg/100g (AG) were achieved at 30MPa. These result suggest that a combination of HPT and germination are efficient method for enhancement of functionality in rough rice, and clarify the influence of HPT conditions on the vitamin E and phenolic acid in germination rough rice.


Assuntos
Germinação , Hidroxibenzoatos/química , Oryza/química , Vitamina E/química , Germinação/fisiologia , Pressão Hidrostática , Hidroxibenzoatos/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Vitamina E/isolamento & purificação
14.
Pharm Biol ; 54(10): 1971-81, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26841303

RESUMO

Context Psidium guajava L. (Myrtaceae) leaves are used in traditional medicines for the treatment of cancer, inflammation and other ailments. Objective The current study explores scientific validation for this traditional medication. Materials and methods We used ferric-reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picryl hydrazil (DPPH) assays to estimate antioxidant activity of P. guajava leaf extracts (methanol, hexane and chloroform). Antitumour and in vivo cytotoxic activities were determined using potato disc assay (PDA) and brine shrimp lethality assay, respectively. Three human carcinoma cell lines (KBM5, SCC4 and U266) were incubated with different doses (10-100 µg/mL) of extracts and the anticancer activity was estimated by MTT assay. NF-κB suppressing activity was determined using electrophoretic mobility shift assay (EMSA). Chemical composition of the three extracts was identified by GC-MS. Total phenolic and flavonoid contents were measured by colorimetric assays. Results and discussions The order of antioxidant activity of three extracts was methanol > chloroform > hexane. The IC50 values ranged from 22.73 to 51.65 µg/mL for KBM5; 22.82 to 70.25 µg/mL for SCC4 and 20.97 to 89.55 µg/mL for U266 cells. The hexane extract exhibited potent antitumour (IC50 value = 65.02 µg/mL) and cytotoxic (LC50 value = 32.18 µg/mL) activities. This extract also completely inhibited the TNF-α induced NF-κB activation in KBM5 cells. GC-MS results showed that pyrogallol, palmitic acid and vitamin E were the major components of methanol, chloroform and hexane extracts. We observed significant (p < 0.05) difference in total phenolic and flavonoid contents of different solvent extracts. Conclusion The present study demonstrates that P. guajava leaf extracts play a substantial role against cancer and down-modulate inflammatory nuclear factor kB.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Psidium , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/toxicidade , Antioxidantes/isolamento & purificação , Antioxidantes/toxicidade , Artemia/efeitos dos fármacos , Compostos de Bifenilo/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaio de Desvio de Mobilidade Eletroforética , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Concentração Inibidora 50 , Dose Letal Mediana , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Ácido Palmítico/isolamento & purificação , Ácido Palmítico/farmacologia , Fitoterapia , Picratos/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Folhas de Planta , Plantas Medicinais , Psidium/química , Pirogalol/isolamento & purificação , Pirogalol/farmacologia , Solventes/química , Vitamina E/isolamento & purificação , Vitamina E/farmacologia
15.
J Agric Food Chem ; 63(40): 8930-9, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26405759

RESUMO

Tocotrienols, a vitamin E subgroup, exert potent anticancer effects, but easily degrade due to oxidation. Eight vitamin E reference compounds, α-, ß-, γ-, or δ-tocopherols or -tocotrienols, were thermally oxidized in n-hexane. The corresponding predominantly dimeric oxidation products were separated from the parent compounds by diol-modified normal-phase HPLC-UV and characterized by mass spectroscopy. The composition of test compounds, that is, α-tocotrienol, γ-tocotrienol, or palm tocotrienol-rich fraction (TRF), before and after thermal oxidation was determined by HPLC-DAD, and MCF-7 cells were treated with both nonoxidized and oxidized test compounds for 72 h. Whereas all nonoxidized test compounds (0-100 µM) led to dose-dependent decreases in cell viability, equimolar oxidized α-tocotrienol had a weaker effect, and oxidized TRF had no such effect. However, the IC50 value of oxidized γ-tocotrienol was lower (85 µM) than that of nonoxidized γ-tocotrienol (134 µM), thereby suggesting that γ-tocotrienol oxidation products are able to reduce tumor cell viability in vitro.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Tocotrienóis/química , Vitamina E/química , Vitamina E/farmacologia , Neoplasias da Mama/fisiopatologia , Divisão Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Células MCF-7 , Oxirredução , Tocotrienóis/farmacologia , Vitamina E/isolamento & purificação
16.
J Med Food ; 18(2): 216-23, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25105230

RESUMO

Vitamin E is an essential human nutrient that was first isolated from wheat. Emmer wheat, the cereal of Old World agriculture and a precursor to durum wheat, grows wild in the Fertile Crescent. Evolution Canyon, Israel, provides a microsite that models effects of contrasting environments. The north-facing and south-facing slopes exhibit low and high stress environments, respectively. Wild emmer wheat seeds were collected from both slopes and seed tocochromanol contents measured to test the hypothesis that high stress alters emmer wheat seed tocol-omics. Seeds from high stress areas contained more total vitamin E (108±15 nmol/g) than seeds from low stress environments (80±17 nmol/g, P=.0004). Vitamin E profiles within samples from these different environments revealed significant differences in isoform concentrations. Within each region, ß- plus γ-tocotrienols represented the highest concentration of wheat tocotrienols (high stress, P<.0001; low stress, P<.0001), while α-tocopherol represented the highest concentration of the tocopherols (high stress, P=.0002; low stress, P<.0001). Percentages of both δ-tocotrienol and δ-tocopherol increased in high stress conditions. Changes under higher stress apparently are due to increased pathway flux toward more tocotrienol production. The production of more δ-isoforms suggests increased flow through a divergent path controlled by the VTE1 gene. Hence, stress conditions alter plant responses such that vitamin E profiles are changed, likely an attempt to provide additional antioxidant activity to promote seed viability and longevity.


Assuntos
Meio Ambiente , Sementes/química , Estresse Fisiológico , Tocotrienóis/análise , Triticum/química , Vitamina E/química , Cromanos/análise , Transferases Intramoleculares , Israel , Vitamina E/análogos & derivados , Vitamina E/análise , Vitamina E/isolamento & purificação , alfa-Tocoferol/análise , gama-Tocoferol/análise
17.
J Oleo Sci ; 63(12): 1243-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25391685

RESUMO

Nowadays, data concerning the composition of Caryodendron orinocense Karst. (Euphorbiaceae) and Bactris gasipaes Kunth (Arecaceae) seed oils are lacking. In light of this fact, in this paper fatty acids and unsaponifiable fraction composition have been determined using GC-MS, HPLC-DAD (Diode Array Detector), NMR approaches and possible future applications have been preliminary investigated through estimation of antioxidant activity, performed with DPPH test. For C. orinocense linoleic acid (85.59%) was the main component, lauric (33.29%) and myristic (27.76%) acids were instead the most abundant in B. gasipaes. C. orinocense unsaponifiable fraction (8.06%) evidenced a remarkable content of ß-sitosterol, campesterol, stigmasterol, squalene and vitamin E (816 ppm). B. gasipaes revealed instead ß-sitosterol and squalene as main constituents of unsaponifiable matter (3.01%). Antioxidant capacity evidenced the best performance of C. orinocense seed oil. These preliminary results could be interesting to suggest the improvement of the population's incomes from Amazonian basin. In particular the knowledge of chemical composition of C. orinocense and B. gasipaes oils could be helpful to divulge and valorize these autochthones plants.


Assuntos
Antioxidantes , Arecaceae/química , Euphorbiaceae/química , Ácidos Graxos/isolamento & purificação , Ácidos Graxos/farmacologia , Nozes/química , Óleos de Plantas/química , Sementes/química , Colesterol/análogos & derivados , Colesterol/análise , Colesterol/isolamento & purificação , Colesterol/farmacologia , Cromatografia Líquida de Alta Pressão , Ácidos Graxos/análise , Sequestradores de Radicais Livres , Cromatografia Gasosa-Espectrometria de Massas , Ácidos Láuricos/análise , Ácidos Láuricos/isolamento & purificação , Ácidos Láuricos/farmacologia , Ácido Linoleico/análise , Ácido Linoleico/isolamento & purificação , Ácido Linoleico/farmacologia , Espectroscopia de Ressonância Magnética , Ácido Mirístico/análise , Ácido Mirístico/isolamento & purificação , Ácido Mirístico/farmacologia , Fitosteróis/análise , Fitosteróis/isolamento & purificação , Fitosteróis/farmacologia , Óleos de Plantas/isolamento & purificação , Sitosteroides/análise , Sitosteroides/isolamento & purificação , Sitosteroides/farmacologia , Esqualeno/análise , Esqualeno/isolamento & purificação , Esqualeno/farmacologia , Estigmasterol/análise , Estigmasterol/isolamento & purificação , Estigmasterol/farmacologia , Vitamina E/análise , Vitamina E/isolamento & purificação , Vitamina E/farmacologia
18.
Sci Rep ; 4: 4086, 2014 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-24522390

RESUMO

In a subendothelial space of atherosclerotic arteries, apolipoprotein B-containing lipoproteins are accumulated and oxidized, and the oxidized lipoproteins promote macrophage foam cell formation. Therefore, the analysis of vitamin E, a major antioxidant in lipoproteins, is important for understanding atherosclerotic pathogenesis. A new method for the automated measurement of vitamin-E (γ- and α-tocopherols) in plasma HDL, LDL, and VLDL was established by using anion-exchange-chromatography for separation of lipoproteins, reverse-phase-chromatography for separation of γ- and α-tocopherols in each of lipoproteins, and fluorescent detection. The within-day assay and between-day assay coefficients of variation for lipoprotein tocopherol levels were 4.73-12.84% and 7.00-14.73%, respectively. The γ- and α-tocopherol/cholesterol ratios of VLDL were higher in healthy plasma than in plasma of untreated patients with dyslipidemia, but the ratios of LDL and HDL were not different. This new estimated method can provide the reliable data of lipoprotein vitamin-E and would be useful for the clinical settings.


Assuntos
Análise Química do Sangue/métodos , Lipoproteínas/sangue , Espectrometria de Fluorescência , Vitamina E/análise , Adulto , Automação , Análise Química do Sangue/instrumentação , Cromatografia por Troca Iônica , Cromatografia de Fase Reversa , Dislipidemias/metabolismo , Dislipidemias/patologia , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Pessoa de Meia-Idade , Vitamina E/isolamento & purificação , alfa-Tocoferol/análise , alfa-Tocoferol/isolamento & purificação , gama-Tocoferol/análise , gama-Tocoferol/isolamento & purificação
19.
Artigo em Inglês | MEDLINE | ID: mdl-24472745

RESUMO

In fish, vitamins are part of the first line of the antioxidant defense, they are directly related to stress and disease, and they are involved in the maintenance of various physiological processes and metabolic reactions. In general, fish are unable to synthesize vitamin C due to a deficiency in gulonolactone oxidase (GLO), the enzyme responsible for its de novo synthesis. Vitamin E is involved in the immune response and perhaps one of its main physiological functions is to protect membranes from oxidative damage (lipid peroxidation) associated with free radical production. In fish muscle, vitamin E has an important role as an antioxidant in vivo and its content is highly related to the stability of lipids and fats. The aim of this study was to determine the content of vitamins C and E in muscle from different species of elasmobranch and teleost fishes. The concentrations of vitamins C and E were determined by high performance liquid chromatography (HPLC). The concentration of vitamin C found for the group of elasmobranchs was lower (p=0.001) than that for teleosts. For Mustelus henlei vitamin C was found in only one individual; in Tetrapturus audax and Totoaba macdonaldi vitamin C concentration was below the detection limit. The concentration of vitamin E was lower in the group of elasmobranchs (p=0.03) compared with that of teleosts. The main differences in the antioxidant system between teleosts and elasmobranchs appear to be the specific type and levels of antioxidant compounds, as well as the synergistic interactions among the antioxidants present in their tissues.


Assuntos
Ácido Ascórbico/isolamento & purificação , Músculo Esquelético/metabolismo , Vitamina E/isolamento & purificação , Animais , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Elasmobrânquios/metabolismo , Peixes/metabolismo , Peroxidação de Lipídeos , Oxirredução , Vitamina E/metabolismo
20.
Biosens Bioelectron ; 47: 127-32, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23567632

RESUMO

This work prepared a novel ionic liquid stabilized molecularly imprinted optosensing material based on quantum dots (QDs) and graphene oxide (GO) composites using a one-step polymerization for highly selective and sensitive specific recognition of vitamin E (VE). Here, GO was first introduced to the molecularly imprinted polymer (MIP) because of its ultra-high specific surface area which increases the rate of mass-transfer relative to that of traditional bulk MIP. The ionic liquid was used to provide the desired surface binding groups between the QDs and the GO, but also to improve their fluorescence stability by virtue of its high thermal and chemical stability. Under optimal conditions, the relative fluorescence intensity of MIP decreased linearly with the increasing concentration of VE in the range of 2.30×10(-2)-9.20×10(2)µM with a detection limit of 3.5nM and the precision for five replicate detections of 92µM VE was 1.67% (relative standard deviation). At three concentration levels, the recoveries for two samples achieved were 93.00-100.14% and 92.00-102.00%, respectively.


Assuntos
Técnicas Biossensoriais , Grafite/química , Pontos Quânticos/química , Vitamina E/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Líquidos Iônicos/química , Limite de Detecção , Impressão Molecular , Óxidos/química , Vitamina E/química
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