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Mario Irano - One of the best experts on this subject based on the ideXlab platform.
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normal phase high performance liquid chromatography method for the determination of tocopherols and tocotrienols in cereals
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Gianfranco Panfili, Alessandra Fratianni, Mario IranoAbstract:The eight vitamers of vitamin E (alpha-, beta-, gamma-, and Delta-Tocopherols and -tocotrienols) have different antioxidant and biological activities and have different distributions in foods. Some cereals, especially oat, rye, and barley, are good sources of tocotrienols. A fast procedure for the determination of tocopherols and tocotrienols (tocols) in cereal foods was developed. It involves sample saponification and extraction followed by normal phase high-performance liquid chromatography (HPLC). The results have been compared with those found by direct extraction without saponification. The method is sensitive and selective enough to be tested on a wide variety of cereal samples. The highest tocol levels were found in soft wheat and barley ( approximately 75 mg/kg of dry weight). beta-Tocotrienol is the main vitamer found in hulled and dehulled wheats (from 33 to 43 mg/kg of dry weight), gamma-tocopherol predominates in maize (45 mg/kg of dry weight) ), and alpha-tocotrienol predominates in oat and barley (56 and 40 mg/kg of dry weight, respectively).
Vasconcelos, Larissa Fernanda Melo - One of the best experts on this subject based on the ideXlab platform.
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Ação da vitamina “E” na modulação do metabolismo lipídico e da tumorigênese na linhagem de câncer de mama triplo negativo MDA-MB-231 suplementada com ácido docosahexaenóico
2016Co-Authors: Vasconcelos, Larissa Fernanda MeloAbstract:INTRODUÇÃO: O ácido graxo poliinsaturado docosahexaenóico (DHA), da família Ômega-3, e a Vitamina E são bastante estudados no microambiente tumoral em virtude da sua atuação como fator de proteção contra a progressão do câncer de mama, porém a atividade desses compostos na biogênese de corpusculos lipídicos em células tumorais ainda é um pouco explorada. OBJETIVO: Investigar a ação de diferentes isoformas da vitamina E (Alfa-tocoferol, Delta-tocoferol e o Delta-tocotrienol) em células da linhagem de câncer de mama MDA-MB-231 suplementadas com DHA, na atuação na modulação do metabolismo lipídico e tumorigênese. METODOLOGIA: Células MDA-MB-231 foram tratadas com o 50 μM de DHA, 5 μM das isoformas de vitamina E ou ambos (coestimulos) para avaliar citotoxicidade, indução de espécies reativas de oxigênio, biogênese de corpúsculos lipídicos, expressão do receptor PPARγ, lipofagia, e parâmetros da carcinogênese como a proliferação, a sobrevivência e a migração celular. RESULTADOS: O DHA e as vitaminas “E” não reduziram a viabilidade das células nas dosagens estudadas, sendo que o DHA aumentou a produção de ROS, e o coestimulo com Delta-Tocotrienol inibiu a produção de ROS. Houve aumento na biogênese de corpúsculos lipídicos nos tratamentos, porém as vitaminas “E” e os coestimulos apresentaram menor expressão de PPARγ. A lipofagia foi identificada nos tratamentos com DHA e DHA + Delta-Tocotrienol. Em relação aos parâmetros de tumorigênese, foi verificado diminuição da migração celular nos tratamentos com DHA e coestimulos de DHA + Delta-Tocoferol e DHA + Delta-Tocotrienol. CONCLUSÃO: A presença das diferentes isoformas de vitamina E modulam a biogênese dos corpúsculos lipídicos, e na presença do Delta-Tocotrienol há maior ocorrência de lipofagia e menor migração celular. ______________________________________________________________________________________________ ABSTRACTINTRODUCTION: Polyunsaturated fatty docosahexaenoic acid (DHA), the omega-3 family, and Vitamin E are extensively studied in the tumor microenvironment by virtue of its role as a protective factor against progression of breast cancer, but the activity of these compounds in biogenesis of lipid droplets in tumor cells is still a little explored. To investigate the action of different isoforms of vitamin E (alpha-tocopherol, Delta-Tocopherol and delta-tocotrienol) in MDA-MB-231 breast cancer cell line supplemented with DHA, in acting in the modulation of lipid metabolism and tumorigenesis. METHODOLOGY: MDA-MB-231 cells were treated with 50μM of DHA, 5μM isoforms of vitamin E or both (coestimulos) to assess cytotoxicity, induction of reactive oxygen species, biogenesis lipid droplets, PPAR gamma receptor expression, lipofagia and carcinogenesis parameters such as proliferation, survival, and cell migration. RESULTS: The DHA and vitamins "E" did not reduce cell viability in the studied dosages, and DHA increased ROS production, and coestimulo with Delta-Tocotrienol inhibited the ROS production. There was an increase in the biogenesis of lipid droplets in treatments, however vitamins "E" and coestimulos had lower expression of PPAR gamma. The lipofagia was identified in the treatments with DHA and DHA + Delta-Tocotrienol. In relation to tumorigenesis parameters, it was found decreased cell migration in treatment with DHA and DHA + coestimulos of Delta-Tocopherol and DHA + Delta-Tocotrienol. CONCLUSION: The presence of different isoforms of vitamin E modulate the biogenesis of lipid droplets, and Delta-Tocotrienol's presence is higher occurrence of lipofagia and lower cell migration
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Ação da vitamina “E” na modulação do metabolismo lipídico e da tumorigênese na linhagem de câncer de mama triplo negativo MDA-MB-231 suplementada com ácido docosahexaenóico
'Biblioteca Central da UNB', 2015Co-Authors: Vasconcelos, Larissa Fernanda MeloAbstract:Dissertação (mestrado)—Universidade de Brasília, Faculdade de Ciências da Saúde, Departamento de Nutrição, Programa de Pós-Graduação em Nutrição Humana, 2015.INTRODUÇÃO: O ácido graxo poliinsaturado docosahexaenóico (DHA), da família Ômega-3, e a Vitamina E são bastante estudados no microambiente tumoral em virtude da sua atuação como fator de proteção contra a progressão do câncer de mama, porém a atividade desses compostos na biogênese de corpusculos lipídicos em células tumorais ainda é um pouco explorada. OBJETIVO: Investigar a ação de diferentes isoformas da vitamina E (Alfa-tocoferol, Delta-tocoferol e o Delta-tocotrienol) em células da linhagem de câncer de mama MDA-MB-231 suplementadas com DHA, na atuação na modulação do metabolismo lipídico e tumorigênese. METODOLOGIA: Células MDA-MB-231 foram tratadas com o 50 μM de DHA, 5 μM das isoformas de vitamina E ou ambos (coestimulos) para avaliar citotoxicidade, indução de espécies reativas de oxigênio, biogênese de corpúsculos lipídicos, expressão do receptor PPARγ, lipofagia, e parâmetros da carcinogênese como a proliferação, a sobrevivência e a migração celular. RESULTADOS: O DHA e as vitaminas “E” não reduziram a viabilidade das células nas dosagens estudadas, sendo que o DHA aumentou a produção de ROS, e o coestimulo com Delta-Tocotrienol inibiu a produção de ROS. Houve aumento na biogênese de corpúsculos lipídicos nos tratamentos, porém as vitaminas “E” e os coestimulos apresentaram menor expressão de PPARγ. A lipofagia foi identificada nos tratamentos com DHA e DHA + Delta-Tocotrienol. Em relação aos parâmetros de tumorigênese, foi verificado diminuição da migração celular nos tratamentos com DHA e coestimulos de DHA + Delta-Tocoferol e DHA + Delta-Tocotrienol. CONCLUSÃO: A presença das diferentes isoformas de vitamina E modulam a biogênese dos corpúsculos lipídicos, e na presença do Delta-Tocotrienol há maior ocorrência de lipofagia e menor migração celular.INTRODUCTION: Polyunsaturated fatty docosahexaenoic acid (DHA), the omega-3 family, and Vitamin E are extensively studied in the tumor microenvironment by virtue of its role as a protective factor against progression of breast cancer, but the activity of these compounds in biogenesis of lipid droplets in tumor cells is still a little explored. To investigate the action of different isoforms of vitamin E (alpha-tocopherol, Delta-Tocopherol and delta-tocotrienol) in MDA-MB-231 breast cancer cell line supplemented with DHA, in acting in the modulation of lipid metabolism and tumorigenesis. METHODOLOGY: MDA-MB-231 cells were treated with 50μM of DHA, 5μM isoforms of vitamin E or both (coestimulos) to assess cytotoxicity, induction of reactive oxygen species, biogenesis lipid droplets, PPAR gamma receptor expression, lipofagia and carcinogenesis parameters such as proliferation, survival, and cell migration. RESULTS: The DHA and vitamins "E" did not reduce cell viability in the studied dosages, and DHA increased ROS production, and coestimulo with Delta-Tocotrienol inhibited the ROS production. There was an increase in the biogenesis of lipid droplets in treatments, however vitamins "E" and coestimulos had lower expression of PPAR gamma. The lipofagia was identified in the treatments with DHA and DHA + Delta-Tocotrienol. In relation to tumorigenesis parameters, it was found decreased cell migration in treatment with DHA and DHA + coestimulos of Delta-Tocopherol and DHA + Delta-Tocotrienol. CONCLUSION: The presence of different isoforms of vitamin E modulate the biogenesis of lipid droplets, and Delta-Tocotrienol's presence is higher occurrence of lipofagia and lower cell migration
A M Lampi - One of the best experts on this subject based on the ideXlab platform.
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Normal-phase high-performance liquid chromatography of tocopherols and tocotrienols. Comparison of different chromatographic columns.
Journal of chromatography. A, 2000Co-Authors: A Kamal-eldi, S Görgen, J Pettersson, A M LampiAbstract:Natural vitamin E is composed of eight different vitamers (alpha-, beta-, gamma- and Delta-Tocopherols and alpha-, beta-, gamma- and delta-tocotrienols). As these eight vitamers have different antioxidant and biological activities, it is necessary to have quantitative data on each substance separately. The aim of this study was to find universal HPLC columns for the separation of all eight components and to test if a few columns of the same material (different batches) will give reproducible results. Normal-phase HPLC separations of vitamin E compounds in a prepared mixture (containing oat extracts, palm oil and tocopherol standards) were tried on six silica, three amino and one diol columns. As shown by calculations of retention factors (k), separation factors (alpha), numbers of theoretical plates (N) and resolutions (Rs), the best separations were obtained on three silica columns and two amino columns using 4 or 5% dioxane in hexane as the mobile phase as well as on a diol column using 4% tert.-butyl methyl ether in hexane as the mobile phase.
Gianfranco Panfili - One of the best experts on this subject based on the ideXlab platform.
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normal phase high performance liquid chromatography method for the determination of tocopherols and tocotrienols in cereals
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Gianfranco Panfili, Alessandra Fratianni, Mario IranoAbstract:The eight vitamers of vitamin E (alpha-, beta-, gamma-, and Delta-Tocopherols and -tocotrienols) have different antioxidant and biological activities and have different distributions in foods. Some cereals, especially oat, rye, and barley, are good sources of tocotrienols. A fast procedure for the determination of tocopherols and tocotrienols (tocols) in cereal foods was developed. It involves sample saponification and extraction followed by normal phase high-performance liquid chromatography (HPLC). The results have been compared with those found by direct extraction without saponification. The method is sensitive and selective enough to be tested on a wide variety of cereal samples. The highest tocol levels were found in soft wheat and barley ( approximately 75 mg/kg of dry weight). beta-Tocotrienol is the main vitamer found in hulled and dehulled wheats (from 33 to 43 mg/kg of dry weight), gamma-tocopherol predominates in maize (45 mg/kg of dry weight) ), and alpha-tocotrienol predominates in oat and barley (56 and 40 mg/kg of dry weight, respectively).
Marie E Olsson - One of the best experts on this subject based on the ideXlab platform.
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tocopherols and tocotrienols in sea buckthorn hippophae rhamnoides l berries during ripening
Journal of Agricultural and Food Chemistry, 2008Co-Authors: Staffan Andersson, Kimmo Rumpunen, Eva Johansson, Marie E OlssonAbstract:Sea buckthorn berries ( Hippophae rhamnoides L.) are used in foods, cosmetics, and pharmaceutical products. They are of particular interest for their high content of healthy phytochemicals, including vitamin E-related compounds (tocopherols and tocotrienols). This study investigated the content of tocopherols and tocotrienols during ripening in berries from four cultivars of sea buckthorn over a three-year period. The results showed large variations in tocopherols and tocotrienols depending on harvest date, cultivar, and year. Levels of alpha-tocopherol were higher early in the ripening period, while at later dates, Delta-Tocopherol levels increased. Great differences in amounts and composition of tocopherols and tocotrienols were observed between cultivars. Tocopherol levels were positively correlated with daily temperature, but this trend varied between years. Variations in tocopherols and tocotrienol levels in sea buckthorn berries due to cultivar, year, and ripening stage should therefore be considered in the production of nutritional products.