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1.
J Sci Food Agric ; 102(14): 6340-6348, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35527679

RESUMO

BACKGROUND: Local leafy vegetables are gaining attention as affordable sources of micronutrients, including vitamins, pro-vitamin carotenoids and other bioactive compounds. Stinging nettles (Urtica spp.) are used as source of fibers, herbal medicine and food. However, despite the relatively wide geographical spread of Urtica leptophylla on the American continent, little is known about its content of vitamin E congeners and carotenoids. We therefore investigated the particular nutritional potential of different plant structures of wild Costa Rican U. leptophylla by focusing on their vitamin E and carotenoid profiles. RESULTS: Young, mature and herbivore-damaged leaves, flowers, stems and petioles were collected and freeze-dried. Vitamin E and carotenoids were determined by high-performance liquid chromatography after liquid/liquid extraction with hexane. α-Tocopherol was the major vitamin E congener in all structures. Flowers had a high content of γ-tocopherol. Herbivore-damaged leaves had higher contents of vitamin E than undamaged leaves. Lutein was the major and ß-carotene the second most abundant carotenoid in U. leptophylla. No differences in carotenoid profiles were observed between damaged and undamaged leaves. CONCLUSION: The leaves of U. leptophylla had the highest nutritional value of all analyzed structures; therefore, they might represent a potential source of α-tocopherol, lutein and ß-carotene. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Urtica dioica , Vitamina E , Carotenoides/análise , Costa Rica , Flores/química , Hexanos , Luteína/análise , Vitamina E/análise , Vitaminas/análise , alfa-Tocoferol/análise , beta Caroteno/análise , gama-Tocoferol/análise
2.
Int J Mol Sci ; 22(17)2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34502281

RESUMO

M. alba L. is a valuable nutraceutical plant rich in potential bioactive compounds with promising anti-gouty arthritis. Here, we have explored bioactives, signaling pathways, and key proteins underlying the anti-gout activity of M. alba L. leaves for the first-time utilizing network pharmacology. Bioactives in M. alba L. leaves were detected through GC-MS (Gas Chromatography-Mass Spectrum) analysis and filtered by Lipinski's rule. Target proteins connected to the filtered compounds and gout were selected from public databases. The overlapping target proteins between bioactives-interacted target proteins and gout-targeted proteins were identified using a Venn diagram. Bioactives-Proteins interactive networking for gout was analyzed to identify potential ligand-target and visualized the rich factor on the R package via the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway on STRING. Finally, a molecular docking test (MDT) between bioactives and target proteins was analyzed via AutoDock Vina. Gene Set Enrichment Analysis (GSEA) demonstrated that mechanisms of M. alba L. leaves against gout were connected to 17 signaling pathways on 26 compounds. AKT1 (AKT Serine/Threonine Kinase 1), γ-Tocopherol, and RAS signaling pathway were selected as a hub target, a key bioactive, and a hub signaling pathway, respectively. Furthermore, three main compounds (γ-Tocopherol, 4-Dehydroxy-N-(4,5-methylenedioxy-2-nitrobenzylidene) tyramine, and Lanosterol acetate) and three key target proteins-AKT1, PRKCA, and PLA2G2A associated with the RAS signaling pathway were noted for their highest affinity on MDT. The identified three key bioactives in M. alba L. leaves might contribute to recovering gouty condition by inactivating the RAS signaling pathway.


Assuntos
Supressores da Gota/farmacologia , Morus/química , Folhas de Planta/química , Proteínas ras/metabolismo , Animais , Avaliação Pré-Clínica de Medicamentos , Cromatografia Gasosa-Espectrometria de Massas , Gota/tratamento farmacológico , Gota/metabolismo , Supressores da Gota/química , Supressores da Gota/toxicidade , Humanos , Simulação de Acoplamento Molecular , Mapas de Interação de Proteínas , Transdução de Sinais/efeitos dos fármacos , gama-Tocoferol/análise , gama-Tocoferol/farmacologia
3.
Anal Bioanal Chem ; 413(2): 577-584, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33205254

RESUMO

For simultaneous analysis of four fat-soluble tocopherols (α-, ß-, γ-, and δ-) in edible oils, an efficient and green method using deep eutectic solvent-based liquid-phase microextraction (DES-LPME) coupled with reversed-phase high-performance liquid chromatography (RP-HPLC) was developed. The DESs formed by different quaternary ammonium salts and ethanol were used as the extractants. Tetrabutylammonium chloride (TBAC)-ethanol DES at a molar ratio of 1:2 achieved the best extraction efficiency. Under the optimized conditions, the detection limits were in the range of 2.1-3.0 ng mL-1. The intra-day and inter-day repeatability were in the ranges of 3.9-5.3% and 4.8-7.1%, respectively, and the recoveries for the real samples varied from 80.7% to 105.4%. The developed method was successfully employed for the determination of all four tocopherol homologues with an RP-HPLC system containing a COSMOSIL π-NAP column in five edible oils collected locally. Graphical abstract.


Assuntos
Microextração em Fase Líquida/métodos , Óleos de Plantas/análise , Solventes/química , Tocoferóis/análise , alfa-Tocoferol/análise , beta-Tocoferol/análise , gama-Tocoferol/análise , Técnicas de Química Analítica , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Compostos de Amônio Quaternário/análise , Reprodutibilidade dos Testes
4.
J Oleo Sci ; 69(11): 1359-1366, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33055442

RESUMO

For the very first time, the nutritional and physicochemical properties of the oil extracted from hackberry Celtis australis fruit were investigated with the aim of possible applications of such wild fruit oil. The physicochemical properties such as peroxide value, acidity, saponification, iodine value and total fat content of the extracted oil were examined extensively. The obtained results showed that peroxide value, acidity, saponification, iodine value and total fat content of the extracted oil were found to be 4.9 meq O2/kg fat, 0.9 mg KOH/g fat, 193.6 mg KOH/g fat, 141.52 mg I2/g fat and ~5%, respectively. The predominant fatty acid found in this wild fruit is linoleic acid which was calculated to be 73.38%±1.24. In addition, gamma-tocopherol (87%) and ß-sitosterol (81.2%±1.08) were the major tocopherol and sterol compositions found in Celtis australis seed oil. Moreover, equivalent carbon number (ECN) analysis has indicated that the three linoleic acids are the main composition of the triacylglycerols extracted from Celtis australis. Also, the high value of omega 6 and ß-sitosterol make this oil applicable in cosmetics and pharmaceutical applications.


Assuntos
Carbono/análise , Ésteres/análise , Ácidos Graxos/análise , Ácido Linoleico/análise , Fitosteróis/análise , Óleos de Plantas/química , Sementes/química , Tocoferóis/análise , Triglicerídeos/análise , Ulmaceae/química , Biofarmácia , Fenômenos Químicos , Cosméticos , Peróxidos/análise , Sitosteroides/análise , Triglicerídeos/química , gama-Tocoferol/análise
5.
J Food Sci ; 85(10): 3043-3051, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32856299

RESUMO

Walnut kernels contain high amounts of polyunsaturated fatty acids that determine a limited shelf life on these nuts. The application of walnut phenolics as antioxidants through a walnut protein-based coating, obtained from walnut oil cake residue, can help to increase the shelf life of walnuts. The objective was to evaluate the preservative effect of walnut polyphenols included in a walnut-proteic edible coating on walnut kernels. Three treatments of walnuts coated with walnut flour were prepared: without the addition of antioxidants (control); with the addition of a walnut phenolic extract; and with the addition of butylated hydroxytoluene (BHT). On the last storage day, the sample with the addition of walnut phenolics presented a lower peroxide (3.64 meq 02 /kg oil) and anisidine value (1.11), conjugated diene (15.92), and hexanal content (19.67 × 106 e.c.) than the control sample (6.23, 1.81, 24.65, and 122.37 × 106 e.c., respectively). Also, on the last day, the control sample showed the highest deterioration of polyunsaturated fatty acids (from 74.83 to 71.08 g/100g), carotenoid (from 3.43 to 1.90 mg/kg), and γ-tocopherol content (from 349.66 to 298.42 mg/kg). In addition, this sample exhibited the highest oxidized (20.33) and the lowest walnut flavor intensity (64.67) on day 84. Regarding consumer acceptance, the phenolic-added sample displayed a greater flavor acceptance score. Walnut phenolics, implemented through a walnut protein-based coating, improve the preservation of walnuts. PRACTICAL APPLICATION: The combination of walnut-phenolic extracts and walnut-based edible coating applied on walnuts by food industries allows to prolong their shelf life, by preserving their nutritional, sensory, and quality properties. Considering the practical feasibility, the procedure used to prepare these products is simple and requires machineries already present in food industries. In addition, the utilization of this coating with walnut-phenolics exerts benefits like, the prevention of allergen cross-contamination in the chain of production, the utilization of an industry's residue, the replacement of synthetic antioxidants and, and the diminishment of the amount and thickness of plastic needed for walnuts' packaging.


Assuntos
Filmes Comestíveis , Juglans/química , Nozes/química , Fenóis/química , Antioxidantes/análise , Hidroxitolueno Butilado/análise , Humanos , Extratos Vegetais/análise , Polifenóis/análise , Paladar , gama-Tocoferol/análise
6.
J Oleo Sci ; 69(5): 423-428, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32378548

RESUMO

A study was carried out to evaluate oil contents, fatty acid composition and tocopherol contents of several walnut types in relation to roasting process. The major fatty acid identified was linoleic acid in both roasted and unroasted walnut oils. Linoleic acid contents of unroasted walnut oil varied from 46.44 (Type 9) and 63.59% (Type 7), while the linoleic acid contents of roasted walnut oils at 120℃/h ranged from 55.95% (Type 3) to 64.86% (Type 10). Interestingly, linolenic acid contents of both roasted and unroasted oils changed between 9.43 (Type 10) and 16.29% (Type 8) to 9.64 (Type 10) and 16.58% (Type 8), respectively and were significant (p < 0.05) different. γ-tocopherol content of unroasted walnut oils varied between 6.3 (Type 3) and 11.4 mg/100g (Type 1) and γ-tocopherol contents of roasted walnut oils ranged between 28.1 (Type 8) and 38.2 mg/100g (Type 3). The oil could be useful for industrial applications owing to good physicochemical properties. Fatty acid values for oil obtained from roasted walnut were slightly higher than those reported for unroasted walnut oils.


Assuntos
Manipulação de Alimentos/métodos , Temperatura Alta , Juglans/química , Óleos de Plantas/análise , Óleos de Plantas/química , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Ácidos Linoleicos/análise , gama-Tocoferol/análise
7.
Food Chem ; 296: 160-166, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31202300

RESUMO

Vitamin E is a family of related compounds with different vitamin E activities and antioxidant properties that includes tocopherols, tocotrienols and plastochromanol-8. Plant oils could serve as an industrial source not only of tocopherols, but also tocotrienols and plastochromanol-8, which exhibit much stronger antioxidant activities than tocopherols. The aim of this study was a quantitative and qualitative analysis of vitamin E in certain plant oils. We demonstrated the presence of vitamin E derivatives in all the plant oils tested. The highest tocopherol contents were in pomegranate, wheat germ and raspberry seed oils. In general, γ-tocopherol was the predominant tocopherol homologue. Tocotrienols were also identified in most of the oils, but their content was much lower. The highest concentration of tocotrienols was in coriander seed oil. Plastochromanol-8 was present in most of the oils, but wheat germ oil was the richest source.


Assuntos
Óleos de Plantas/química , Vitamina E/análise , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Rubus/química , Rubus/metabolismo , Tocotrienóis/análise , gama-Tocoferol/análise
8.
Food Res Int ; 121: 880-887, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31108821

RESUMO

Monguba fruit has a seed with a chestnut-like flavor that can be consumed boiled, fried, and roasted. These nutritious seeds also have been used in popular medicine to treat several diseases. Nevertheless, the nutritional and functional potential of monguba seed is still underexploited. In this sense, we investigated the nutritional and functional components of monguba seeds. These seeds showed high total content of sugars, mainly sucrose, whereas the content of the raffinose family oligosaccharides was low. The mineral assay showed high amount of minerals, namely potassium, calcium, magnesium and zinc, which indicate that monguba seeds can be a new source of these minerals. UHPLC-ESI-MS/MS analysis showed caffeic, ferulic and 4-hydroxybenzoic acids as the main phenolic compounds, mainly in the esterified form, in these seeds. Monguba seed showed high lipid content, in which the main compounds were palmitic acid and γ-tocopherol. The soluble and insoluble phenolic fractions from monguba seeds showed high antioxidant activity measured by the oxygen radical absorption capacity (ORAC) and the trolox equivalent antioxidant capacity (TEAC) assays. Therefore, the monguba seeds have great potential to be explored by food, pharmaceutical and cosmetic industries due to their chemical composition.


Assuntos
Antioxidantes/análise , Bombacaceae/química , Sementes/química , Ácidos Cafeicos/análise , Fenômenos Químicos , Cromanos/análise , Ácidos Cumáricos/análise , Ácidos Graxos/análise , Frutas/química , Nozes/química , Ácido Palmítico/análise , Parabenos/análise , Fenóis/análise , Extratos Vegetais/análise , Óleos de Plantas/química , Potássio/análise , Rafinose/análise , Espectrometria de Massas em Tandem , gama-Tocoferol/análise
9.
Food Res Int ; 114: 230-239, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30361021

RESUMO

The effect of γ-tocopherol in proportions between 0.02 and 2% by weight on the accelerated storage process of refined soybean oil is studied by 1H NMR, and compared with that of α-tocopherol. Whereas the lowest γ-tocopherol enrichment level does not affect oil evolution, at higher concentrations both γ- and α-tocopherols initially accelerate acyl groups degradation and hydroperoxides generation, more as higher is the tocopherol concentration, this effect being less marked for γ-tocopherol. However, after this initial stage, the rates of acyl groups degradation and hydroperoxides formation decrease with tocopherol concentration. Furthermore, in the case of γ-tocopherol, the higher the enrichment degree, the later hydroperoxides decomposition occurs, so that, unlike α-tocopherol, γ-tocopherol delays the generation of most secondary oxidation products (aldehydes, (E,E)-keto-dienes, epoxy-keto-enes, (E)-epoxystearates and alcohols) with the exception of some epoxides. Similarly to α-tocopherol, γ-tocopherol modifies the oil oxidation pathway at the highest addition level, promoting the formation of compounds with (Z,E)-isomerism, although less noticeably than α-tocopherol.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Óleo de Soja , gama-Tocoferol , Armazenamento de Alimentos , Compostos Orgânicos/análise , Compostos Orgânicos/química , Oxirredução , Óleo de Soja/análise , Óleo de Soja/química , alfa-Tocoferol/análise , alfa-Tocoferol/química , gama-Tocoferol/análise , gama-Tocoferol/química
10.
J Food Sci ; 83(3): 617-623, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29355957

RESUMO

Eucommia ulmoides seed oil is the main byproduct of E. ulmoides cultivation. To better understand its functions, E. ulmoides seed oil is characterized comprehensively in this work. The composition of E. ulmoides seed, physicochemical properties, thermal properties, fatty acid composition, triacylglycerol (TAG) composition and Vitamin E composition of E. ulmoides seed oil were determined. The results show that the E. ulmoides seed contained about 34.63% oil. The excellent physicochemical properties of E. ulmoides seed oil ensured it has a potential to be developed as an edible oil. The main fatty acids in E. ulmoides seed oil were linolenic acid (61.36%), oleic acid (17.02%), and linoleic acid (12.04%). HPLC-ELSD method determined that LnLnLn (37.99%), LnLnO (22.62%), LnLnL (14.5%), and LnLnP (8.78%) were the oil's major TAG components. The oil exhibited a unique thermal curve which contained 2 melting peaks at -38.45 and -22.22 °C, respectively. The total content of vitamin E in E. ulmoides seed oil was 190.96 mg/100g, which exist mainly in γ-tocopherol and δ-tocopherol isomer. Overall, the results indicated that E. ulmoides seed oil is a promising oil in food, pharmaceutics, cosmetics and other nonfood industries.


Assuntos
Eucommiaceae/química , Óleos de Plantas/química , Ácido alfa-Linolênico/química , Cromatografia Líquida de Alta Pressão , Ácidos Graxos/química , Ácido Linoleico/análise , Ácido Oleico/análise , Sementes/química , Tocoferóis/análise , Triglicerídeos/análise , Vitamina E/análise , gama-Tocoferol/análise
11.
J Food Sci ; 83(3): 624-630, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29377104

RESUMO

This investigation aimed to evaluate the chemical composition and physicochemical properties of seed oils from 6 date palm (Phoenix. dactylifera L.) cultivars (Barhi, Khalas, Manifi, Rezeiz, Sulaj, and Sukkari) growing in Saudi Arabia and to compare them with conventional palm olein. The mean oil content of the seeds was about 7%. Oleic acid (48.67%) was the main fatty acid, followed by lauric acid (17.26%), stearic acid (10.74%), palmitic acid (9.88%), and linolenic acid (8.13%). The mean value for free fatty acids content was 0.5%. The P. dactylifera seed oil also exhibited a mean tocol content of 70.75 mg/100 g. α-Tocotrienol was the most abundant isomer (30.19%), followed by γ-tocopherol (23.61%), γ-tocotrienol (19.07%), and α-tocopherol (17.52%). The oils showed high thermal and oxidative stabilities. The findings indicate that date seed oil has the potential to be used in the food industry as an abundant alternative to palm olein. PRACTICAL APPLICATION: This study showed that date seed had great nutritional value due to which it can be used for food applications especially as frying or cooking oil. In addition, date oil has also potential to be used in cosmetic and pharmaceutical practices as well. The extraction of oil from Phoenix dactylifera seed on large scale can create positive socioeconomic benefits especially for rural communities and could also assist to resolve the environmental issues generated by excess date production in large scale date-producing countries such as Saudi Arabia.


Assuntos
Phoeniceae/química , Óleos de Plantas/química , Ácidos Graxos/química , Ácidos Láuricos/química , Valor Nutritivo , Ácido Oleico/química , Oxirredução , Phoeniceae/classificação , Arábia Saudita , Sementes/química , Ácidos Esteáricos/química , Tocotrienóis/química , gama-Tocoferol/análise
12.
J Oleo Sci ; 67(1): 39-45, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29311522

RESUMO

Oil content and bioactive properties of almond and walnut kernels were investigated in developing almond and walnut kernels at 10 days intervals. The oil contents of almond and walnuts after the first harvest (1.H) stage changed between 46.2% and 55.0% to 39.1% and 70.5%, respectively (p<0.05). Oleic acid contents of almond and walnut oils ranged from 71.98% (1.H) to 78.68% (5.H) and 10.51% (1.H) to 16.78% (2.H) depending on harvest (H) times, respectively (p<0.05). In addition, linolenic acid contents of walnut and almond oils were found between 62.35% and 67.78%, and 12.02% and 17.65%, respectively. The almond kernel oil after the first harvest stage contained 1.045, 1.058, 1.018, 0.995 and 0.819 mg/kg ɑ-tocopherol, respectively. γ-Tocopherol contents of walnut oil changed between 1.364 (3.H) and 2.954 mg/kg (1.H). The ß-sitosterol contents of both almond and walnut oils were found between 1956.6 (5.H) and 2557.7 (1.H), and 1192.1 (3.H) and 4426.4 mg/kg (1.H). The study exhibited the presence of high percentage of oleic and linoleic for almond and walnut, respectively, and γ-tocopherol and ß-sitosterol.


Assuntos
Produtos Agrícolas/química , Juglans/química , Ácidos Oleicos/análise , Óleos de Plantas/análise , Prunus dulcis/química , Sitosteroides/análise , Ácido alfa-Linolênico/análise , alfa-Tocoferol/análise , gama-Tocoferol/análise , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Óleos de Plantas/química , Fatores de Tempo
13.
J Food Sci ; 82(2): 553-561, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28135396

RESUMO

Eight wild species in Sect. Moutan DC (tree peony) of the genus Paeonia grown in natural habitats and 1 cultivated specie were investigated to analyze their fatty acid and bioactive phenolic compound profiles. For fatty acid composition, P. ludlowii contained the lowest α-linolenic acid (27.68%) and P. jishanensis contained the highest (51.96 %) content of the 9 species. For phenolic compounds, P. qiui contained the highest resveratrol (2.12 mg/g), P. delavayi contained the highest ß-gentiobiosylpaeoniflorin (26.23 mg/g), and P. ostii contained the highest paeoniflorin (23.66 mg/g). P. ostii was selected to perform a feasibility study because of its relatively high level of α-linolenic acid 46.53%, low in ω-6 to ω-3 ratio of 1:2, and high level of the preferred bioactive phenolic compounds l including paeoniflorin and resveratrol. Physical pressing and refining process were conducted to obtain P. ostii seed oil. It exhibited bland sensory attributes described as slight grassy, very slight nutty, no painty or fishy aroma and slight grassy, slight nutty flavor with a very slight throat catch. Tocol results reported high level in tree peony seed oil 223.5 ± 13.65 mg/100 g with γ-tocopherol 70.1 ± 2.14 mg/100 g, and γ-tocotrienol 149.6 ± 15.83 mg/g. Because of the high total tocol, γ-tocopherol and γ-tocotrienol levels, and tree peony seed oil exhibited better oxidation stability than flaxseed oil even with similar α-linolenic acid levels. In addition, high levels of γ-tocopherol and γ-tocotrienol can introduce therapeutic effects such as antiinflammation and antioxidation. Therefore, this study showed that tree peony seed oil has a great potential to be used in edible oil, nutraceutical supplement, and other health care products.


Assuntos
Análise de Alimentos/métodos , Paeonia/química , Sementes/química , Ácido alfa-Linolênico/análise , gama-Tocoferol/análise , Antioxidantes/análise , Cromanos/análise , Estudos de Viabilidade , Glucosídeos/análise , Óleo de Semente do Linho/análise , Monoterpenos/análise , Valor Nutritivo , Oxirredução , Fenóis/análise , Resveratrol , Especificidade da Espécie , Estilbenos/análise , Árvores , Vitamina E/análogos & derivados , Vitamina E/análise
14.
Food Chem ; 220: 306-312, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27855904

RESUMO

Oxidation products and tocol homologues were monitored in oils during chicken frying to determine the discarding point of highly used frying oils. Oils were heated without chicken for 170h while chicken frying was performed 130 cycles at 180°C. As heating time and frying cycles increased, all oxidation parameters including acid value, total polar materials (TPM), conjugated dienoic acid (CDA), and p-anisidine values (p-AV) increased significantly (p<0.05). γ-Tocopherol and γ-tocotrienol had the lowest stability in oils during heating or frying processes compared to other tocol homologues. TPM values over 24% were obtained after about 109h for heated oil and 100 cycles for oils used to fry chicken. A decrease of 2,2-diphenyl-1-picrylhydrazyl (DPPH) in isooctane and methanol was highly correlated with the formation of TPM in oils during the frying process. Both DPPH loss and TPM values could be applied to determine the discarding points of highly used frying oils.


Assuntos
Ácidos/química , Antioxidantes/química , Culinária , Óleos de Plantas/química , Compostos de Anilina/análise , Animais , Compostos de Bifenilo/análise , Galinhas , Cromanos/análise , Temperatura Alta , Oxirredução , Picratos/análise , Aves Domésticas , Vitamina E/análogos & derivados , Vitamina E/análise , gama-Tocoferol/análise
15.
Molecules ; 20(8): 14777-90, 2015 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-26287138

RESUMO

The reactivity of tocopherols with 2,2-diphenyl-1-picrylhydrazyl (DPPH) was studied in model systems in order to establish a method for quantifying vitamin E in plant oils. The method was optimized with respect to solvent composition of the assay medium, which has a large influence on the course of reaction of tocopherols with DPPH. The rate of reaction of α-tocopherol with DPPH is higher than that of γ-tocopherol in both protic and aprotic solvents. In ethyl acetate, routinely applied for the analysis of antioxidant potential (AOP) of plant oils, reactions of tocopherols with DPPH are slower and concentration of tocopherols in the assay has a large influence on their molar reactivity. In 2-propanol, however, two electrons are exchanged for both α- and γ-tocopherols, independent of their concentration. 2-propanol is not toxic and is fully compatible with polypropylene labware. The chromatographically determined content of tocopherols and their molar reactivity in the DPPH assay reveal that only tocopherols contribute to the AOP of sunflower oil, whereas the contribution of tocopherols to the AOP of linseed oil is 75%. The DPPH assay in 2-propanol can be applied for rapid and cheap estimation of vitamin E content in plant oils where tocopherols are major antioxidants.


Assuntos
Bioensaio/métodos , Linho/química , Óleos de Plantas/química , Tocoferóis/análise , 2-Propanol/química , Acetatos/química , Antioxidantes/análise , Compostos de Bifenilo/química , Cinética , Oxirredução , Picratos/química , Solventes , Óleo de Girassol , Vitamina E/análise , alfa-Tocoferol/análise , gama-Tocoferol/análise
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 Sci Food Agric ; 95(13): 2571-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25472416

RESUMO

Although sesame seed oil contains high levels of unsaturated fatty acids and even a small amount of free fatty acids in its unrefined flavored form, it shows markedly greater stability than other dietary vegetable oils. The good stability of sesame seed oil against autoxidation has been ascribed not only to its inherent lignans and tocopherols but also to browning reaction products generated when sesame seeds are roasted. Also, there is a strong synergistic effect among these components. The lignans in sesame seed oil can be categorized into two types, i.e. inherent lignans (sesamin, sesamolin) and lignans mainly formed during the oil production process (sesamol, sesamolinol, etc.). The most abundant tocopherol in sesame seed oil is γ-tocopherol. This article reviews the antioxidant activities of lignans and tocopherols as well as the browning reaction and its products in sesame seed and/or its oil. It is concluded that the composition and structure of browning reaction products and their impacts on sesame ingredients need to be further studied to better explain the remaining mysteries of sesame oil.


Assuntos
Antioxidantes/farmacologia , Benzodioxóis/farmacologia , Dioxóis/farmacologia , Lignanas/farmacologia , Fenóis/farmacologia , Sementes/química , Óleo de Gergelim/química , Sesamum/química , gama-Tocoferol/farmacologia , Antioxidantes/análise , Benzodioxóis/análise , Dieta , Dioxóis/análise , Humanos , Lignanas/análise , Fenóis/análise , gama-Tocoferol/análise
18.
J Food Sci ; 79(5): C795-801, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24754875

RESUMO

UNLABELLED: Seed oils with high polyunsaturated fatty acid content are used in various industries including the food and pharmaceutical industries. White mahlab (Prunus mahaleb L.) seed was found to contain 31% oil. The oil was highly polyunsaturated and abundant in α-eleostearic (38.32%), oleic (31.29%), and linoleic (22.96%) acids, which together comprised 93.91% of the total fatty acids. The α-eleostearic acid was identified and characterized based on (1)H-NMR, UV, and FTIR spectroscopy. The oil was characterized by a relatively high quantity of tocopherols with γ-tocopherol as the major tocopherol isomer. The physicochemical characteristics of the white mahlab seed and seed oil were also determined. The thermogravimetric analysis indicated that the oil was thermally stable up to 350 °C and began to decompose at 520 °C. This study demonstrated that these seeds may be reused and their oil incorporated into other food products, a beneficial practice considering that the compounds present in the seeds and oils have positive effects on human health. PRACTICAL APPLICATION: In this study, mahlab seed oil was found to have potentials to become a new edible oil source as it contained a high level of polyunsaturated fatty acids especially, α-eleostearic acid, which is a conjugated fatty acid rarely found in vegetable oils and has a beneficial effects on human health.


Assuntos
Ácidos Graxos Insaturados/análise , Ácidos Linolênicos/análise , Óleos de Plantas/química , Prunus/química , Sementes/química , Tocoferóis/análise , gama-Tocoferol/análise
19.
J Sci Food Agric ; 94(13): 2649-54, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24574041

RESUMO

BACKGROUND: Quantification of γ- and α-tocopherol in dry-cured shoulders of Iberian pigs was evaluated as a tool for differentiating feeding backgrounds or regimens. Samples (n = 115) were obtained over two different seasons from the four categories of pigs described in the Industry Quality Policy, i.e. pigs fed in free-range conditions (FREE-RANGE), pigs fed in free-range conditions and provided feed supplements (FREE-FEED), pigs fed outdoors with feed and with access to grass (FEED-OUT) and pigs fed in intensive conditions with feed (FEED). Linear discriminant functions were calculated and validated. RESULTS: The validation results showed that 20% of the muscle samples were not correctly classified into the four feeding categories, giving an 80% success rate. The FEED group had the lowest proportion of errors, with 100% of samples correctly classified. For the FREE-RANGE group, 87% of samples were assigned to the correct feeding system by cross-validation; however, 13% were considered as FREE-FEED. A higher rate of correct classification can be obtained when using three categories or by calculating the weight gain in free-range conditions using regression equations. CONCLUSION: Taking into account the high variability of the samples and the high success in classification, these results are of interest and may be applied in practical situations.


Assuntos
Dieta/veterinária , Inspeção de Alimentos/métodos , Qualidade dos Alimentos , Alimentos em Conserva/análise , Carne/análise , alfa-Tocoferol/análise , gama-Tocoferol/análise , Criação de Animais Domésticos , Animais , Animais Endogâmicos , Antioxidantes/análise , Antioxidantes/metabolismo , Análise Discriminante , Alimentos em Conserva/normas , Florestas , Modelos Lineares , Carne/normas , Músculo Esquelético/química , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Reconhecimento Automatizado de Padrão , Ombro , Espanha , Sus scrofa , Aumento de Peso , alfa-Tocoferol/metabolismo , gama-Tocoferol/metabolismo
20.
J Food Sci ; 78(1): C43-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23278764

RESUMO

UNLABELLED: The desired mix of alpha-linolenic acid (ALA)-enriched structured lipid (SL) and physically blended lipid (PB) was prepared from grape seed oil and perilla oil at a weight ratio of 3:1. The major triacylglycerol species (LnLnL) in PB was drastically increased after interesterification (SL), from 0.5% to 16.8%. After the reaction, the total unsaturated fatty acid at the sn-2 position was decreased from 98.83% in PB to 91.36% in SL. The reduction of vitamin E compounds was also observed. Compared with a PB-based emulsion, SL-based emulsions showed oxidative instability, as assessed by lipid hydroperoxide (LOOH) and 2-thiobarbituric acid-reactive substances (TBARS) values, which was mainly due to the SL which contained less LA, ALA, and ΣUSFA at the sn-2 position and less γ-tocopherol than did PB. PB-, and SL-based emulsions with Ginkgo biloba extract (GBE) which showed significantly lower values of LOOH and TBARS compared to a blank control. GBE was effective in retarding the oxidation of the emulsion by quenching the free radicals in the water phase of the emulsion and inhibiting the formation of primary and secondary oxidation products. These results indicate that GBE could be used as an antioxidant additive for stabilizing ALA-enriched emulsions. PRACTICAL APPLICATION: The results suggest the possibility to supplement Ginkgo biloba extract in alpha linolenic acid-enriched structured lipid-based emulsions which would increase the therapeutic value and enhance the antioxidant potential of the emulsions.


Assuntos
Antioxidantes/farmacologia , Ginkgo biloba/química , Extratos Vegetais/análise , Ácido alfa-Linolênico/análise , Antioxidantes/análise , Emulsões , Gorduras/química , Peróxidos Lipídicos/análise , Oxirredução , Óleos de Plantas/análise , Óleos de Plantas/química , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Triglicerídeos/análise , Ácido alfa-Linolênico/química , gama-Tocoferol/análise
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