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1.
Nutrients ; 15(18)2023 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-37764798

RESUMEN

Mycelial cultures of Lentinula edodes, an edible and medicinal mushroom, have been used in our previous research to obtain selenium-containing immunomodulatory preparations. Our current attempts to obtain a new preparation containing both selenium and zinc, two micronutrients necessary for the functioning of the immune system, extended our interest in the simultaneous accumulation of these elements by mycelia growing in media enriched with selenite and zinc(II) ions. Subsequently, we have studied the effects of new L. edodes mycelium water extracts with different concentrations of selenium and zinc on the activation of T cell fraction in human peripheral blood mononuclear cells (PBMCs). Flow cytometry analysis was used to measure the expression of activation markers on human CD4+ and CD8+ T cells stimulated by anti-CD3 and anti-CD3/CD28 antibodies (Abs). It was demonstrated that statistically significant changes were observed for PD-1 and CD25 antigens on CD8+ T cells. The selenium and zinc content in the examined preparations modified the immunomodulatory activity of mycelial polysaccharides; however, the mechanisms of action of various active ingredients in the mycelial extracts seem to be different.


Asunto(s)
Selenio , Hongos Shiitake , Humanos , Selenio/farmacología , Leucocitos Mononucleares , Suplementos Dietéticos , Micelio
2.
Acta Sci Pol Technol Aliment ; 19(4): 405-423, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33179481

RESUMEN

BACKGROUND: One of the requirements for proper nutrition and maintenance of good health is to supply the body, through diet, with an appropriately increased quantity of bioactive compounds. With this in mind, modern milling and baking industries keep introducing new types of products. The use of such additives as wholegrain flours and bran in baked products provided the basis for research in this paper. METHODS: The aim of the study was to conduct a qualitative and quantitative evaluation of marketable wheat, barley and oat grain, used as raw materials to produce dehulled kernels, ground grain, wholemeal flour and wheat flour type 550 (all-purpose or plain flour), as well as wheat bran. Additionally, analyses were performed to determine the chemical composition and contents of nutrients, selected bioactive compounds and antioxidant activity. RESULTS: The studied raw materials in commercial cereal differ in their chemical composition. Dehulling of wheat, barley and oat grains significantly contributed to the reduction of minerals, protein and total dietary fiber (TDF) contents, except for the amount of protein in dehulled wheat and oat grains. Oat bran, in contrast to other oat products, was characterized by the highest contents of minerals, protein, TDF, and the smallest amounts of saccharides and total starch. The lowest content of minerals was recorded in wheat flour type 550. Thermal processes affect the concentration of tocochromanols in the grain, with tocotrienols being more resistant to hydrothermal treatment than tocopherols. Grain dehulling also significantly decreased the total amount of tocochromanols in relation to the original grains. CONCLUSIONS: Wheat products differ in the contents of their individual components. They are characterized by high contents of tocochromanols, phenolic compounds and water-extractable arabinoxylans, with the exception of white refined wheat flour, which is mainly a source of saccharides. In the case of barley and oat products, the analysis showed no differences between these product groups. It was also shown that dehulling of barley and oat grain causes statistically significant differences in the contents of nutrients and natural antioxidants.


Asunto(s)
Avena/química , Grano Comestible/química , Hordeum/química , Triticum/química , Antioxidantes/análisis , Harina , Manipulación de Alimentos , Calor , Humanos , Minerales/análisis , Nutrientes/análisis , Fenoles/análisis , Tocotrienoles/análisis , Granos Enteros/química , Xilanos/análisis
3.
Acta Sci Pol Technol Aliment ; 19(2): 139-147, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32600010

RESUMEN

BACKGROUND: Tocotrienols found in certain plant oils, like palm, rice bran, grapeseed and annatto seeds, have been reported to possess beneficial properties for humans, including cancer prevention. Since studies on their beneficial effects on human breast cancer cells have been extensively reviewed, the current understanding of how tocotrienols affect other cancer cells deserves further research. Therefore, the aim of this study was to investigate the antiproliferative and non-cytotoxic effects of tocotrienols on human hepatoma HepG2 and colon colorectal Caco-2 cell cultures. METHODS: The cells were exposed to alpha-, beta-, gamma- or delta-tocotrienols at various concentrations and the antiproliferative activities were measured using MTS-based CellTiter 96 followed by a methylene blue assay for counting cells to evaluate the potential toxicity. RESULTS: The research on HepG2 showed statistically similar cytotoxic effects for both beta- and delta-T3 with no effects for alpha- and gamma-T3. Promising results were found for alpha-, beta- and gamma-T3 against CaCo-2. CONCLUSIONS: The exact reasons for the sensitivity of liver cancer cells to tocotrienols are unknown. Inhibition is time and dose-dependent, therefore tocotrienols' homologs show very high toxic or no effects. Tocotrienols appeared to be effective against colon cancer cells. Still, future investigation is necessary to explain the different mechanism of actions to support the antiproliferative effects of these homologs against colon cancer cells.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Tocotrienoles/uso terapéutico , Antineoplásicos/farmacología , Células CACO-2 , Proliferación Celular/efectos de los fármacos , Células Hep G2 , Humanos , Aceites de Plantas/química , Tocotrienoles/farmacología
4.
J Food Biochem ; 43(2): e12707, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-31353667

RESUMEN

In the ongoing discussion on the health properties of palm oil, a study of the effect a diet supplemented with palm oil on blood and liver biochemical parameters, beta-carotene and tocochromanols content as well as antioxidant activity was undertaken. Forty Wistar rats were randomly divided into five groups, fed with a diet supplemented with plant-based frying commercial fat, palm oil, 7.5% palm oil and 2.5% concentrate from palm oil and 10% of rapeseed oil, respectively. After 21 days, blood samples and livers were collected to determine beta-carotene and tocochromanols concentrations, antioxidant activity using DPPH* radical scavenging activity and TEAC methods, insulin, glucagon, serum triacyloglycerols and cholesterol levels, glucose in blood serum and glycogen in the livers. Research has shown valuable biological properties of palm oil in terms of plasma glucose, total cholesterol, low-density lipoprotein (LDL) cholesterol, and triacylglycerol concentrations which was related to the high content of beta-carotene and tocochromanols. PRACTICAL APPLICATION: Public concern over the health properties of palm oil has been growing. Therefore, this study supplements existing knowledge in this area based on experimental rat observations. In the presented research, plasma glucose was significantly reduced and no additional growth of total or LDL cholesterol, as well as triacylglycerol concentration, was observed after consuming a palm oil-based diet. Palm oil was a good source of beta-carotene and tocochromanols, which were preferentially distributed in rats' livers. Bioavailability of vitamin E-active compounds in palm oil supplemented rats' livers was relatively high as compared to the rapeseed oil group, therefore this observation complements literature in the field of tocotrienols and tocopherols. Studies have not confirmed the harmful effect of palm oil on rats, however in depth human studies appear to be a promising direction for further research.


Asunto(s)
Antioxidantes/metabolismo , Cromanos/metabolismo , Hígado/metabolismo , Aceite de Palma/metabolismo , beta Caroteno/sangre , Animales , Colesterol/sangre , Femenino , Glucógeno/metabolismo , Masculino , Ratas , Ratas Wistar , Triglicéridos/sangre
5.
J Sci Food Agric ; 98(9): 3263-3270, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29230831

RESUMEN

BACKGROUND: The aim of the study was to determine the effect of genotype × environment interaction on the levels of α-, ß-, γ- and δ-tocopherol (α-T, ß-T, γ-T and δ-T, respectively) and plastochromanol-8 (PC-8) in seeds of 17 doubled haploids (DHs) obtained from the F1 hybrid derived from crossing black (DH H2 -26) × yellow (DH Z-114) seeds of winter oilseed rape. RESULTS: The content of tocopherols in the tested DH lines ranged from 415.6 to 540.1 mg kg-1 seeds, while PC-8 content ranged from 56.3 to 89.0 mg kg-1 seeds. The α-T/γ-T ratio reached a level of 0.78-1.29. Studies have shown that heritability for α-T, ß-T, γ-T, total-T and PC-8 is mainly due to genotypic variation. For the δ-T homologue the level was dependent on environmental effect. CONCLUSION: The obtained DH lines population of oilseed rape is characterized by high heritability coefficients for α-T, ß-T, γ-T, total-T and PC-8 levels, which indicates a greater influence of genotype than the environment on the content of these compounds. Among all studied doubled haploids, seven DHs were selected which were characterized by stable contents of α-T, ß-T, γ-T, δ-T and total-T with the simultaneous stable content of PC-8. © 2017 Society of Chemical Industry.


Asunto(s)
Brassica napus/química , Cromanos/análisis , Interacción Gen-Ambiente , Semillas/química , Tocoferoles/análisis , Vitamina E/análogos & derivados , Brassica napus/genética , Ambiente , Variación Genética , Genotipo , Haploidia , Estaciones del Año , Vitamina E/análisis
6.
Food Chem ; 225: 239-245, 2017 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-28193421

RESUMEN

A physicochemical characteristic of the cold-pressed oil obtained from seeds of common beech (Fagus sylvatica L.) has been presented. This plant may be considered as unconventional oilseeds crops because of relatively high content of fat (27.25%). The analyzed beech seeds oil has been classified as oleic-linoleic acids oil with more than 76% percentage share of those species. Beech seeds oil contains 4.2% of gamma-linolenic acid (GLA). Unique characteristic is the high content of γ-tocopherol (75.4mg/100g) and δ-tocopherol (34.05mg/100g). γ-Tocopherol is effective scavengers of reactive nitrogen species and prevents DNA bases nitration, what makes beech seeds oil interesting raw material in the production of cosmetics. Additionally the content of carotenoids, very effective photooxidation inhibitors, is at high level in comparison with other cold-pressed oils. It was demonstrated that PCA analysis may help to determine the authenticity of oil obtained from beech seeds.


Asunto(s)
Fagus/química , Aceites de Plantas/química , Semillas/química , Fenómenos Químicos
7.
Acta Sci Pol Technol Aliment ; 15(3): 321-332, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28071031

RESUMEN

BACKGROUND: In the study, an analysis of tocopherols, plastochomanol-8 and phytosterols was conducted using DH lines obtained from F1 hybrids of reciprocal crosses between yellow- and black-seeded lines. METHODS: The biological material for the study consisted of two DH populations of winter oilseed rape obtained from F1 hybrids of reciprocal crosses between two DH lines: yellow- and black-seeded. Seed color was determined using a ColorFlex spectrophotometer. Fat content was determined via pulsed NMR. The levels of tocopherols, and plastochromanol-8 are analyzed using HPLC. Phytosterol contents and composition were determined by the GC method. RESULTS: The fat content of the black-seeded parental line was 49% and this was higher than that of the yellow-seeded parental line (44%). The fat content of DH line populations ranged from 44 to 51%. Total tocopherol content ranged from 460 to 602 mg/kg and the α-T/γ-T ratio was from 0.66 to 1.09. In parental lines H2-26 and Z-114 the total tocopherol content was 534 and 525 mg/kg, but the α-T/γ-T ratios were 0.81 and 1.21, respectively. The yellow-seeded parental line (Z-114) was characterized by a higher PC-8 content (81 mg/kg) than the H2-26 black-seeded parental line (58 mg/kg). The largest part of the total phytosterol content in seeds of both populations was ß-sitosterol from 976 to 2148 mg/kg, followed by campasterol, from 636 to 1364 mg/kg, and brassicasterol from 375 to 678 mg/kg. The total tocopherol content ranged from 462 to 595 mg/kg (population HxZ) and from 460 to 602 mg/kg (population ZxH). Significantly positive correlations were observed between the seed color with α-T (r = 0.38, p < 0.01), γ-T (r = -0,34, p < 0.01) and PC-8 content (r = 0.29, p < 0.01). Correlations between the seed color with total tocopherol and total phytosterol content were not noted. CONCLUSIONS: Considering the range of genetic variation among doubled haploids of two populations, selected DH lines may be good parents for further breeding programs focused on increasing the amount and improving the quality of oilseed rapeseed oil. However, further studies will also be made to determine the influence of the environment on bioactive compounds in rapeseed oil. Cross direction of parental DH lines: yellow- and black-seeded has some influence, albeit not statistically significant, on the diversity of doubled haploid in their populations with regard to average fat, tocochromanol and phytosterol content.


Asunto(s)
Brassica napus/química , Cromanos/análisis , Fitosteroles/análisis , Semillas/química , Tocoferoles/análisis , Vitamina E/análogos & derivados , Colestadienoles/análisis , Ácidos Grasos/análisis , Haploidia , Sitoesteroles/análisis , Vitamina E/análisis
8.
Artículo en Inglés | MEDLINE | ID: mdl-25978020

RESUMEN

Changes of the photoluminescent properties of QD in the presence of oxidized catechin (CQ) were investigated by absorption, steady-state fluorescence, fluorescence lifetime and dynamic light scattering measurements. Photoluminescence intensity and fluorescence lifetime was decreasing with increasing CQ concentration. Dynamic light scattering technique found the hydrodynamic diameter of QD suspension in water is in range of 45 nm, whereas in presence of CQ increased to mean values of 67 nm. Calculated from absorption peak position of excition band indicated on average QD size of 3.2 nm. Emission spectroscopy and time-resolved emission studies confirmed preservation of electronic band structure in QD-CQ aggregates. On basis of the presented results, the elucidated mechanism of QD fluorescence quenching is a result of the interaction between QD and CQ due to electron transfer and electrostatic attraction. The results of fluorescence quenching of water-soluble CdTe quantum dot (QD) capped with thiocarboxylic acid were used to implement a simple and fast method to determine the presence of native antioxidant quinones in aqueous solutions. Feasibility studies on this method carried out with oxidized catechin showed a linear relation between the QD emission and quencher concentration, in range from 1 up to 200 µM. The wide linear range of concentration dependence makes it possible to apply this method for the fast and sensitive detection of quinones in solutions.


Asunto(s)
Compuestos de Cadmio/química , Catequina/química , Puntos Cuánticos/química , Quinonas/química , Telurio/química , Dispersión Dinámica de Luz , Estudios de Factibilidad , Luminiscencia , Oxidación-Reducción , Soluciones , Espectrometría de Fluorescencia
9.
Arch Med Sci ; 8(2): 256-62, 2012 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-22661998

RESUMEN

INTRODUCTION: Plasma antioxidant vitamins (retinol, α-tocopherol, ß-carotene) were measured to establish the influence of clinical condition and mycophenolate mofetil (MMF) treatment on the nutritional status of renal transplant recipients. MATERIAL AND METHODS: In 106 adult patients plasma vitamins were measured and 24-h diet history questionnaires were conducted. The MMF influence on plasma vitamins was verified in 61 patients. RESULTS: The current dietary intakes of vitamins in daily food rations were lower than recommended. Plasma retinol was lower in patients suffering from gastrointestinal disorders (1.25 ±0.48 mg/l vs. 1.55 ±0.70 mg/l) and inversely associated with aminotransferases activity (p = 0.019) and creatinine clearance (p = 0.021). Retinol concentrations were positively associated with plasma creatinine (p = 0.027) and pharmacokinetic parameters of MMF phenyl glucuronide. ß-Carotene concentrations were higher in women (0.39 ±0.46 mg/l vs. 0.28 ±0.23 mg/l; p = 0.041) and when MMF was co-administered with cyclosporine vs. tacrolimus (0.45 ±0.62 mg/l vs. 0.25 ±0.19 mg/l). Plasma α-tocopherol correlated negatively with the mycophenolic acid pre-dose concentration (p = 0.027) and was significantly lower in patients treated with calcineurin inhibitors (8.90 ±5.23 mg/l vs. 12.25 ±5.62 mg/l). A positive correlation was observed between α-tocopherol levels and aspartate aminotransferase (p = 0.006). In multivariate regression aspartate aminotransferase and MMF treatment significantly influenced retinol (p < 0.001). CONCLUSIONS: The MMF treatment was associated with significantly lower retinol concentrations. The gastrointestinal disorders occurrence in MMF-treated patients may cause a decrease in retinol absorption. Diet adjustment and/or vitamin A supplementation should be considered.

10.
J Am Oil Chem Soc ; 89(3): 379-387, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22514355

RESUMEN

The focus of the present research was to study inhibition of lipoxygenase activity by rapeseed native polyphenols and the interactions between those compounds and the enzyme. The enzyme and polyphenolic compounds (polyphenols, phenolic acids) were extracted from rapeseed (Brassica napus) varieties Aviso and PR45DO3. The total phenolic compounds concentration in tested rapeseed was 1,485-1,691 mg/100 g d.m. (dry matter) and the free phenolic acids content in both rapeseed varieties was about 76 µg/100 g d.m. The isolated proteins showed lipoxygenase activity. Prooxidant properties of phenolic compounds in the presence of lipoxygenase and linoleic acid were observed rather in the case of extracts containing a relatively high concentration of miscellaneous polyphenols. Antioxidant properties were recorded in the case of phenolic acid extracts which contain only 1.4-1.9% of phenolics present in raw phenolic extracts. We propose that the prooxidant effect of phenolic compounds comes from quinone and oxidized polyphenols formation. The observed antioxidant activity of phenolic acid extracts is probably due to their ability to scavenge free radicals formed from linoleic acid. However, reduction of lipoxygenase ferric to ferrous ions, which prevent the activation of the enzyme and inhibited its activity, was also observed.

11.
J Agric Food Chem ; 60(7): 1830-6, 2012 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-22264085

RESUMEN

Lupin seed globulin proteins form complexes with flavonoids, predominantly apigenin C-glycosides. Enzymes typical for the gastrointestinal tract were used to hydrolyze lupin seed globulins. Release of native flavonoids as a result of the proteolysis reaction was observed. Different analytical methods such as size exclusion chromatography, HPLC-MS, and fluorescence spectroscopy (steady-state fluorescence, fluorescence anisotropy, fluorescence lifetimes) were used for a detailed characterization of this phenomenon. Flavonoids liberated from lupin globulin proteins as a result of pancreatin-catalyzed digestion were bound by γ-conglutin resistant to this enzyme. Two possible mechanisms of this interaction may be suggested: hydrogen bonding between oligosaccharide chains of glycoproteins and the sugar moieties of the flavonoid glycosides or electrostatic attraction between positively charged γ-conglutin and flavonoids partially ionized at pH 7.5.


Asunto(s)
Digestión , Flavonoides/metabolismo , Globulinas/metabolismo , Lupinus/química , Proteínas de Plantas/metabolismo , Semillas/química , Apigenina/metabolismo , Modelos Biológicos , Pancreatina/metabolismo , Proteolisis
12.
Acta Pol Pharm ; 64(1): 45-51, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17665850

RESUMEN

To obtain rich in organic forms of zinc extracts of Lentinus edodes, possessing putative higher immunostimulating properties than actually used, mycelia were cultivated in zinc(II) enriched media. Culture media were enriched in zinc in concentration ranging from 0 to 90 microg mL(-1), added to the medium before inoculation. Total zinc concentration in submerged cultivated mycelial biomass has been determined by the use of atomic absorption spectroscopy method (AAS). Zinc concentration expressed in mg% of mycelial dry mass rose from 0,33 microg g(-1), estimated for mycelium cultivated in not enriched in Zn(II) medium, to 4,28 microg g(-1) for mycelium cultured in medium containing 50 microg mL(-1) of zinc. Higher than 50 microg mL(-1) concentration of Zn(II) in medium caused a decrease of zinc content in mycelial dry mass. Zinc concentration in the medium strongly affected the mycelial growth. Productivity of the mycelium rose proportionally to the increase of Zn(II) concentration in the medium. The highest mycelial growth was recorded for media containing Zn(II) in concentration of 50 microg mL(-1). Concentration of Zn(II) in the medium upper than 50 microg mL(-1) acted depressing on the mycelial growth. An optimal pH of the medium for zinc accumulation was estimated by cultivation of Lentinus edodes mycelia in media of pH ranging from 3,5 to 7, containing 50 microg mL(-1) of zinc(II). The optimal pH of the medium for zinc accumulation was 7. Proportionally to the increasing concentration of zinc(II) in the medium rose the percentage of this metal adsorbed on the cell surface, easy to remove by washing of the mycelium with the 0,05 molar EDTA solution. The value of the percentage of zinc adsorbed on the cell surface changed in the range from 30% to 70% for concentrations of Zn(II) in the medium rising from 20 to 110 microg mL(-1).


Asunto(s)
Micelio/química , Extractos Vegetales/química , Hongos Shiitake/química , Zinc/farmacocinética , Absorción , Membrana Celular , Medios de Cultivo/química , Suplementos Dietéticos , Eficiencia , Concentración de Iones de Hidrógeno , Micelio/efectos de los fármacos , Micelio/crecimiento & desarrollo , Espectrofotometría Atómica , Zinc/química
13.
Molecules ; 12(12): 2643-57, 2007 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-18259149

RESUMEN

This paper describes a modified method of preparation of a number of alpha-aryl-alpha-(pyridazin-3-yl)-acetonitriles via the C-arylation reaction of the corresponding carbanionsof phenylacetonitriles using 3-chloropyridazine derivatives. KOH and DMSO were used inthe deprotonation process, which made the reaction very simple and safe to perform.Nitriles were obtained in the hydrolysis reaction to the corresponding alpha-aryl-alpha-(pyridazin-3-yl)-acetamide derivatives, which were next subjected to cyclization to afford the finalproducts. A number of new derivatives of 7H,8H-pyrimido[1,6-b]pyridazin-6,8-dione weresynthesized in the cyclocondensation reaction of respective alpha-aryl-alpha-(pyridazin-3-yl)-acetamides with diethyl carbonate in the presence of EtONa. The structure andcomposition of the new compounds were confirmed by IR, (1)H- and (13)C- NMR analysesand by elemental C, H and N analysis.


Asunto(s)
Piridazinas/síntesis química , Espectroscopía de Resonancia Magnética , Piridazinas/química
14.
Cell Mol Biol Lett ; 12(1): 51-69, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17124545

RESUMEN

The effects of embedding up to 60 mol% of alpha-tocopherol (alpha-Toc) on the morphology and structure of the egg phosphatidylcholine (PC) membrane were studied using spectroscopic techniques. The resulting vesicles were subjected to turbidometric and dynamic light scattering measurements to evaluate their size distribution. The alpha-Toc intrinsic fluorescence and its quenching was used to estimate the tocopherol position in the membrane. Optical microscopy was used to visualize morphological changes in the vesicles during the inclusion of tocopherol into the 2 mg/ml PC membrane. The incorporation of up to 15 mol% of tocopherol molecules into PC vesicles is accompanied by a linear increase in the fluorescence intensity and the simultaneous formation of larger, multilamellar vesicles. Increasing the tocopherol concentration above 20 mol% induced structural and morphological changes leading to the disappearance of micrometer-sized vesicles and the formation of small unilamellar vesicles of size ranging from 30 to 120 nm, mixed micelles and non-lamellar structures.


Asunto(s)
Yema de Huevo/química , Fosfatidilcolinas/metabolismo , Liposomas Unilamelares/metabolismo , alfa-Tocoferol/farmacología , Relación Dosis-Respuesta a Droga , Yema de Huevo/efectos de los fármacos , Yema de Huevo/efectos de la radiación , Luz , Nefelometría y Turbidimetría , Dispersión de Radiación , Espectrometría de Fluorescencia , Liposomas Unilamelares/efectos de la radiación
15.
Nahrung ; 48(1): 34-7, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15053348

RESUMEN

During the last stage of plant oil refining, deodorization distillates containing very important biological substances such as tocopherols, sterols, terpenoids or hydrocarbons are formed as a by-products. This study aimed at evaluating the content and antioxidant capacity of tocopherol concentrates from deodorization distillates obtained after the refining of rapeseed, soybean and sunflower oil. The majority of the matrix substances were eliminated from deodorization distillates by freezing with an acetone solution at -70 degrees C. The tocopherol concentrates obtained in this way contained approximately fivefold more tocopherols than the quantity in condensates after deodorization. Antioxidant activity was investigated by observing the peroxide value at 25 degrees C and using the Oxidograph test. The test medium was lard enriched with the tocopherol concentrates of the three plant oils versus single, synthetic alpha-, gamma- and delta-tocopherols (-T), which served for comparison. In these model systems, all investigated tocopherol concentrates exhibited antioxidant capacity. Their antioxidant effect was significantly lower than that of single delta-T and gamma-T, but significantly higher than alpha-T. The results prove that natural tocopherol concentrates obtained from plant oils are valuable food antioxidants and they also increase the biological and nutritional value of food especially when administered to animal fats or food of animal origin. Tocopherol concentrates can fully replace synthetic antioxidants that have been used thus far.


Asunto(s)
Antioxidantes/análisis , Aceites de Plantas/química , Tocoferoles/análisis , Tocoferoles/metabolismo , Antioxidantes/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Valor Nutritivo , Oxidación-Reducción , Temperatura , alfa-Tocoferol/análisis , alfa-Tocoferol/metabolismo , gamma-Tocoferol/análisis , gamma-Tocoferol/metabolismo
16.
Nahrung ; 47(5): 286-90, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14609081

RESUMEN

Determination of influence of lupin natural phenolic compounds on antibacterial properties of its seeds was carried out. Raw material were seeds of Lupinus albus, L. luteus, and L. angustifolius. The methods included the determination of the content of proteins, total phenolic compounds, free phenolic acids, and tannins as well as antibacterial properties with ethanol extracts. The content of total phenolic compounds was smaller in testas than in cotyledons and the highest levels are observed in bitter cultivars of Lupinus albus cv. Bac and L. angustifolius cv. Mirela. Lupin tannins mainly occurred in cotyledons of the white lupin, predominantly in the bitter cultivar Bac. Free phenolic acids were mainly found in testas. Only extracts from the testas displayed antibacterial properties, which excludes the possibility of alkaloid influence on the results. The results suggest that inhibition of test bacteria growth depended mainly upon the content of the total phenolic compounds.


Asunto(s)
Antibacterianos/farmacología , Bacillus subtilis/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Lupinus/química , Fenoles/farmacología , Semillas/química , Antibacterianos/análisis , Bacillus subtilis/crecimiento & desarrollo , Cromatografía Líquida de Alta Presión , Escherichia coli/crecimiento & desarrollo , Fenoles/análisis , Extractos Vegetales/análisis , Proteínas de Plantas/análisis , Proteínas de Plantas/farmacología , Taninos/análisis
17.
Nahrung ; 47(2): 74-8, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12744282

RESUMEN

The stability of plant oils is related to the level of polyunsaturated fatty acids and the presence of native antioxidants--especially tocopherols. During storage, lipids or the fat products undergo oxidation and tocopherol dimers and trimers are formed. These compounds possess reducing and antioxidant properties and participate in oxidation clearly inhibiting this process. In the present study, the correlation between levels of peroxides formed during autoxidation of methyl linoleate and simultaneous decomposition of tocopherols was examined. The peroxide value was investigated. Quantities of decomposed tocopherols and formation of their dimers were determined by high-performance liquid chromatography (HPLC). Mass spectrum analysis confirmed thatthe analysed compounds were dimes. Dimerisation of gamma-T begins at the smaller quantity of the methyl linoleate peroxides than dimerisation of delta-T. At the beginning of methyl linoleate autoxidation dimerisation of gamma-T in relation to its loss was smaller. The quantity of gamma-T dimers with ether bonds in total dimers pointed to faster binding of phenoxy radicals than transformation into the phenyl ones. delta-T dimers with phenyl bonds constitute about 65% of the total. The quantity of peroxides in methyl linoleate, necessary for quantitative and qualitative changes of homologous tocopherols, decreased from delta-T to alpha-T.


Asunto(s)
Antioxidantes/química , Peróxidos Lipídicos/química , Tocoferoles/química , Cromatografía Líquida de Alta Presión , Dimerización , Ácidos Linoleicos/química , Espectrometría de Masas , Oxidación-Reducción , Aceites de Plantas/química
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