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Tan, Sue See. "Antioxidant properties of tocopherol and tocotrienol". Thesis, University of Reading, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494987.
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Tocopherols and tocotrienols are very important antioxidants in biological systems. This thesis describes a study of the effect of structure and environmental conditions on the stability and antioxidant activity of tocopherols and tocotrienols in lipoxygenasecatalysed oxidation and in heated oils at elevated temperatures. In the first phase of the project, the mechanism by which α-, β- ,γ-, and δ-tocopherol homologues inhibit lipoxygenase catalysed oxidation of linoleic acid was studied. Primary oxidation products formed during lipoxygenase catalysed oxidation were monitored by determination of conjugated diene formation at 234 nm.
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Park, Han-A. "Natural Vitamin E, α-Tocotrienol, as a Neuroprotectant". The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1291061955.
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Fu, Ju Yen. "Preparation and evaluation of tumour-targeted delivery systems for tocotrienol". Thesis, University of Strathclyde, 2010. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=22629.
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Tocotrienol, a group of compounds present in vitamin E, has gained much attention in recent years for its tumour suppressive properties on cancer cells. However, its therapeutic potential was hampered by the limited ability to reach tumours specifically after intravenous administration. In this study, we aim to develop a formulation of tocotrienol that could be specifically delivered to tumours upon intravenous administration through the use of a tumour-targeted delivery system. Transferrin is an iron transporter whose receptors are often over-expressed in cancer cells due to high iron demand for tumour growth. Conjugation of transferrin to drug delivery systems appeared to be an attractive tool for selective receptor-mediated tumour delivery of therapeutic drugs. The objectives of this study are therefore (1) to prepare and characterize transferrin-bearing vesicles encapsulating tocotrienol and (2) to evaluate in vitro and in vivo the therapeutic and targeting efficacies of this therapeutic system. This work corresponds to the first preparation of a tumour-targeted delivery system able to encapsulate tocotrienol. The grafting of transferrin to tocotrienol-loaded vesicles demonstrated an improved therapeutic efficacy of tocotrienol to at-least 15-fold compared to free tocotrienol in vitro. Intravenous administration of tocotrienol therapeutic systems led to significant tumour regression and improvement in animal survival in murine xenograft models without visible toxicity. In conclusion, our findings showed that tocotrienol encapsulated in transferrin-bearing vesicles is a highly promising therapeutic system, leading to possible eradication of tumours as a result of significant improvement in tocotrienol therapeutic efficacy.
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Gerling, Eva-Maria [Verfasser]. "Stabilität von Vitamin E (α-Tocotrienol, α- Tocopherol, γ-Tocotrienol und γ-Tocopherol) in Rohwürsten und Pökellake: Einfluss von Zusatzstoffen und Lagerung / Eva-Maria Gerling". Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2015. http://d-nb.info/1073848388/34.
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Rosa, Maria Thereza de Moraes Gomes 1986. "Aplicação e potencial das tecnologias de micronização e emulsificação para o processamento de produtos alimentícios e farmacêuticos = Applications and potential of micronization and emulsification technologies in food and pharmaceutical processing". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254914.
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Orientadores: Maria Angela de Almeida Meireles Petenate, Diego Tresinari dos SantosTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O presente trabalho de doutorado está dividido em dois temas principais, um sobre o uso da tecnologia supercrítica para a formação de partículas e outro sobre o uso do ultrassom para a formulação de emulsões. A revisão da literatura sobre o estado da arte do emprego do CO2 supercrítico para formação de micro e nanopartículas e encapsulação mostrou as potencialidades do uso desta tecnologia. A unidade usada para os experimentos de micronização via tecnologia supercrítica foi desenvolvida pelo grupo de pesquisa e validada utilizando uma substância modelo, o sal de ibuprofeno sódico. Esse fármaco foi selecionado devido às informações sobre o sistema CO2-Ibuprofeno encontradas na literatura. O efeito das condições operacionais (temperatura, pressão, vazão da solução, vazão do CO2, tipo de injetor e concentração de ibuprofeno sódico na solução etanólica) no rendimento de precipitação, teor de solvente residual, morfologia das partículas e consumo energético por unidade de produto processado foi investigado utilizando o método split-plot. Sal de ibuprofeno sódico foi micronizado com sucesso via Antissolvente Supercrítico (SAS) utilizando a unidade construída. A vazão de CO2 influenciou estatisticamente no rendimento de precipitação, enquanto que, não houve influência das condições operacionais no teor de solvente residual das partículas micronizadas. Com a apropriada seleção das condições operacionais, foi possível a obtenção de partículas de ibuprofeno sódico com morfologia de folha, sendo ideal para os processos de compressão do fármaco, com baixo teor de solvente residual e alto rendimento de precipitação. Neste trabalho também foi explorado o uso do ultrassom para a formulação de emulsões, contendo extrato rico em 'delta'-tocotrienol, com o intuito de aumentar o valor agregado deste extrato obtido das sementes de urucum por extração supercrítica com dióxido de carbono. As sementes de urucum já são valiosas pela característica de produzir pigmentos, a bixina e a norbixina. Contudo, essas sementes também vêm adquirindo notoriedade por conter outras substâncias de importância para a saúde do homem, como tocoferóis, tocotrienóis e geranil geraniol. Devido à importância desses compostos bioativos, que apresentam propriedades antioxidade, hidratante e fotoprotetora, este estudo visou o desenvolvimento de métodos para formação de emulsões permitindo a proteção desses compostos instáveis às condições adversas, aumentando assim o valor agregado dos extratos obtidos das sementes de urucum. Extrato de raiz de ginseng brasileiro, rico em saponinas, foi utilizado como biossurfactante. Adicionalmente, emulsões foram obtidas utilizando um homogeneizador tipo dispersor de fase múltipla na mesma densidade energética que foi aplicada no ultrassom. A influência do processo de emulsificação, densidade energética, concentração do biosurfactante, tipo de óleo e de biosurfactante no tamanho de gota e estabilidade da emulsão foi investigada. Os resultados indicaram que o extrato rico em saponinas pode ser uma boa opção para formulação de emulsões para aplicação em produtos alimentícios. Miniemulsões, com tamanho de gota variando entre 0,35 e 0,83 µm, foram obtidas, sendo que os menores tamanhos de gota foram observados empregando o extrato de raiz de ginseng e o ultrassom. O processo de emulsificação influenciou estatisticamente a estabilidade das emulsões
Abstract: The presented doctoral work is divided into two main themes under which one is about the use of supercritical technology for particle formation and the another one about the use of ultrasound for emulsion formulation. A literature review about the state of the art in using supercritical CO2 for micro and nanoparticles formation and encapsulation showed the potential of this technology. A homemade experimental apparatuses constructed by our research group and used for micro and nanoparticles formation has been validated using a model substance, the ibuprofen sodium salt. This drug was selected due to the literature information of the CO2-Ibuprofen system. The effect of operational conditions (temperature, pressure, CO2 flow rate, solution flow rate, injector and concentration of ibuprofen sodium in the ethanol solution) on the precipitation yield, energy consumption per unit of manufactured product, residual solvent content and particle morphology have been investigated using split-plot designs. Ibuprofen sodium salt was successfully micronized by Antisolvent Supercritical (SAS) using the constructed unit. The CO2 flow rate influenced the precipitation yield at statistically significant levels meanwhile none operating parameters did influence the residual solvent content in the micronized particles. Selecting appropriate process conditions, it has been shown to facilitate the production of homogeneous sheet-like microparticles of ibuprofen particles, the best for tableting purposes, with low residual solvent and high precipitation yield. In this work, the use of ultrasound has been also explored for fabricating microemulsion of 'delta'-tocotrienol-rich oil in order to add value to these extracts obtained from annatto seeds using supercritical extraction (SFE). The main pigments of annatto seeds are bixin and norbixin, wich are valuable natural colorants. However, these seeds have acquired notoriety by containing other important substances for human health, such as tocopherols, tocotrienols and geranylgeraniol. Due to the bioactive compounds importance, which have moisturizers, sunscreens and antioxidant properties, this study aimed to develop methods for emulsion formulation enabling the protection of these unstable compounds to adverse conditions, thus increasing the value of extracts from annatto seeds. Saponin-rich extract from Brazilian ginseng roots was used as biosurfactant. Additionally, emulsion was generated through mechanical stirring by dispax Reactor at the same energy density than ultrasound. The influence of the emulsification process, energy density, oil type, biosurfactant type and biosurfactant concentration on the size and stability of the resulting droplets was investigated. The results indicated that saponin-rich extract might be an attractive biosurfactant choice for emulsion formulations for use in food and beverage products. Mini-emulsions were obtained in this work; their droplet sizes ranged from 0.35 to 0.83 µm, saponin-rich extract and ultrasound gave the smallest droplet size. The emulsification process significantly affected the emulsion stability values
Doutorado
Engenharia de Alimentos
Doutora em Engenharia de Alimentos
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Fobi, Kwabena, Bronson Lynn i Abbas Gholipour Shilabin. "Extraction, Purification, and Characterization of Radioprotective Agent gamma-Tocotrienol Isomer in Palm Oil". Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/asrf/2019/schedule/188.
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The clinical consequences of ionizing radiation exposure remain one of the leading causes of death in the United States. Much research has been carried out to discover a potential countermeasure for acute radiation syndrome (ARS) without success. The United States Food and Drug Administration (US FDA) has not accepted any effective and harmless ionizing radiation therapy agents (radioprotectors) for treating ARS. It has recently been discovered that g-tocotrienol (GT-3), one of the E vitamers chiefly present in palm oil, has radioprotective abilities in mice and nonhuman primate (NHP) models. Though GT-3 is one of the most promising countermeasures discovered, the separation and purification from other vitamers or its matrix is difficult. This has limited its characterization, derivatization, and biomedical application. We have therefore designed novel chromatographic methods to optimize separation and purification. Thin layer chromatography (TLC) was used to ascertain the best solvent system for column chromatography (CC). Exactly 8% ethyl acetate in hexane employed in TLC and CC resulted in good separation (Rf ≥ 0.3) and purification. Various fractions presumed to contain GT-3 were collected and analyzed to confirm the exact structure using 1H NMR, 13C NMR, DEPT, and GC-MS. Results obtained so far have revealed the exact structure of the compound. However, some traces of impurities have been indicated by the NMR outcomes; therefore, high-performance liquid chromatography (HPLC) will be used to maximize GT-3 purification. This present study will be instrumental in elucidating the biochemical structure of various complex plant bioactive components that are hard to isolate and analyze. It is envisioned that this work will help to erase the knowledge deficit in medicinal chemistry and assist in the development of new medications for ARS.
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Muenyi, Christian Mbangha. "Vitamin E (Tocotrienols) and Prostate Cancer: A Proteomics Approach". Digital Commons @ East Tennessee State University, 2007. https://dc.etsu.edu/etd/2126.
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Proteomics is the large scale study of proteins in cells or organisms. The purpose of this study was to characterize the proteomic alterations occurring in a prostate cancer (LNCaP) cell line after treatment with delta-tocotrienol (a form of vitamin E not very prevalent from most dietary sources). We found that both gamma- and delta-tocotrienols induced time and concentration dependent growth inhibition and programmed cell dead (apoptosis) in LNCaP cells. Secondly, we used two-dimensional gel electrophoresis (2-DE) to characterize changes in protein expression levels associated with this treatment. Our results show that a specific set of proteins are regulated at both early and late times following treatment with delta-tocotrienol and these proteins have been characterized by their apparent molecular weights and isoelectric points. The alteration observed at early time points are particularly interesting because these changes are likely to reflect the underlying molecular mechanisms for triggering cancer cell death.
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Moka, Nagaishwarya, Kelley cross, Marianne Brannon, Janet Lightner, Megan Dycus, William Stone, Victoria Palau i Koyamangalath Krishnan. "Delta-tocotrienol and simvastatin induces differential cytotoxicity and synergy in BRAF wild-type SK-MEL-2 and mutant BRAF SK-MEL-28 melanoma cancer cells". Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/asrf/2018/schedule/215.
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Targeting the mutant BRAF and immunotherapy are new approaches to the treatment of metastatic malignant melanoma that has significantly improved survival but is associated with significant toxicity and cost. Potent and specific BRAF inhibitors like vemurafenib and dabrafenib are superior to chemotherapy in treatment of BRAF mutant melanomas which represent nearly 50% of all melanomas. A less toxic approach to treatment of malignant melanoma is hence appealing. Delta-tocotrienol (DT3), an unsaturated vitamin E isoform, and simvastatin, an HMG-CoA reductase inhibitor have been shown to have anti-neoplastic properties. We studied the effects of these chemicals in both BRAF-mutated SK-MEL-28 and BRAF-wild type SK-MEL-2 melanoma cells. MTS assays were used to analyze cytotoxicity. SK-MEL-28 and SK-MEL-2 cells were cultured in MEM media containing 10% serum and plated in 96-well culture plates for 48 hours then treated with DT3 (0-80 µM), simvastatin (0-10 µM), or a combination and dosed again at 72 hours. SK-MEL-28 and SK-MEL-2 cells were grown in 60 mm plates and treated with DT3 at concentrations of 30 µM, simvastatin at concentrations of 10 µM and combination of DT3 and simvastatin at concentrations of 10 µM and 2 µM. Cell were lysed with RIPPA buffer with protease and phosphatase inhibitor after 6 hours of treatment. Protein concentration of cell lysates was measured spectrophotometrically (GLO Max Multi+, Promega), using a BCA protein assay kit. The samples were run in SDS PAGE and blotted onto nitrocellulose membranes. Membranes were incubated with antibodies against Hsp 70 (Enzo Life Sciences, Farmingdale, NY), Hsp 90 (Santa Cruz, Dallas, TX), pS6 and pERK (Cell Signaling, Danvers, MA) and pAKT. Using MTS assay, we found that DT3 (IC50 75.2 μM) and simvastatin (IC50 8.3μM) have cytotoxic effects on melanoma cell line SK-MEL-2, but not on the SK-MEL-28 cells DT3 and simvastatin at the concentrations studied (10-80 μM DT3) and (0.625- 10 μM simvastatin). Further studies determined that simvastatin decreased expression of pS6, pERK on SK-MEL-2 and not DT3. However, these effects are different in SK-MEL-28 cells where there is only decrease in expression of pS6; treated SK-MEL-2 cells also show over-expression of Hsp70 suggestive of a rescue effect leading to lesser cytotoxic activity. The selective cytotoxicity observed in wild type BRAF melanoma cell lines by DT3 and simvastatin warrants further research into the potential therapeutic use of these drugs. A differential cytotoxicity is shown by DT3 and simvastatin in malignant melanoma cells with selective more potency in wild type BRAF melanoma compared to mutant BRAF melanoma cells. Further studies will be undertaken to dissect the mechanistic basis of this differential response.
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Shipley, Lindsey C. BS, Harika MD Balagoni, Janet Lightner, Victoria PhD Palau i Koyamangalath MD Krishnan. "15 Lox 1 Up-regulation and Cytotoxicity with γ-tocotrienol in HCT-116 Colon Cancer Cells". Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/asrf/2018/schedule/154.
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Colorectal cancer is the second leading cause of cancer-related deaths in the United States and the third most common cancer in men and women. Vitamin E is a lipid soluble antioxidant that exists as eight structurally different isoforms of tocopherols and tocotrienols. Recent experimental, and molecular studies suggest that γ-tocotrienol (GT3) may be a more potent cancer-preventive form of vitamin E. 15-lipoxygenase-1 (15-LOX-1) and its product 13-S-hydroxyoctadecadienoic acid (13-S-HODE) are decreased in colon cancer cells. 15 LOX-1 is considered a tumor suppressor gene in colon carcinogenesis. Non-steroidal anti-inflammatory drug (NSAID)-induced 15-LOX-1 expression is critical to aspirin and NSAID-induced apoptosis in colorectal cancer cells. HCT-116 is a microsatellite-instability (MSI) colon cancer cell line. MSI is a marker of chemo-resistance but is associated with improved survival as compared to microsatellite-stable (MSS) colon cancers. The effects of GT3 on cytotoxicity and 15 LOX-1 expression was studied on the human colon cancer cell line HCT-116. HCT-116 colon cancer cell lines were cultured in DMEM media and dosed with increasing concentrations of GT3 (20µM-50µM). Cytotoxicity of the drugs was studied using Cell Titer Glo and MTS assays 24 hours after dosing. Cells were then plated in 6-well plates and grown for 24 hours. Cells were then dosed with 2 mL of GT3 at 20 uM at the respective time periods (2h, 4h, 6h, 12h, 16h, 24h) and lysates were harvested. Gel electrophoresis was run according to BCA protein assay from the time-dependent lysates and blots were tagged with a rabbit 15-lox antibody. Ongoing experiments include RNA PCR. RNA is being isolated at 2, 4, 6 and 12 hours. The RNA as reversed transcribed using a 15 lox 1 primer and that cDNA is being quantified using Quantitative PCR. GT3 induced cytotoxicity in MTS assay and Cell Titer Glo assay when added to HCT-116 cell line. 15 LOX 1 protein expression was found to be up-regulated in the colon cancer cell line HCT-116 when GT3 was added at 12h, 16h and 24h with the maximum expression at 16 hours. Chemotherapeutic drugs can have significant side effects. Understanding the role of GT3 on colon cancer cell lines could lead to the development of novel drugs to supplement current chemotherapy regimens and allow for lower doses of chemotherapeutic agents. Modulation of 15-LOX-1 suggests that GT3 may induce apoptosis through induction of the lipoxygenase pathway. Further experiments are under way to study the mechanism of action of GT3 on the 15 LOX-1 pathway. Since HCT-116 is a MSI- colon cancer cell line, effects of GT3 on MSS- colon cancer cell lines will also be studied.
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Luk, Sze-ue. "The potential effect of bioactive food supplements in targeting prostate cancer stem cells". Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43223795.
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Silva, Dulce Helena Siqueira. "Constituintes químicos de Iryanthera sagotiana e Iryanthera lancifolia". Universidade de São Paulo, 1997. http://www.teses.usp.br/teses/disponiveis/46/46135/tde-28112014-151532/.
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O presente trabalho descreve o isolamento, identificação e determinação estrutural dos constituintes químicos das inflorescências e folhas de Iryanthera sagotiana e das inflorescências e pericarpos de I. lancifolia, espécies da família Myristicaceae, que ocorrem na Amazônia. A investigação fitoquímica das inflorescências de I. sagotiana (Benth.) Warb. forneceu, após extração, partição com solventes orgânicos e fracionamentos cromatográficos, quatro diidrochalconas: 2\',4\'-diidroxi-4,6\'- dimetoxidiidrochalcona (I) ; 2\',4\',6\'-triidróxi-4-metoxidiidrochalcona; 2\',4,4\'-triidróxi-6\'-metoxidiidrochalcona (II) e 2\',4\'-diidroxi-4-metóxi-6\'-glicopiranosil-diidrochalcona, sendo as duas últimas, inéditas. Foram também isolados e identificados o benzaldeído, o ácido diidro-p-cumárico, dois flavonóis glicosilados: afzelina e quercitrina e quatro flavanonóis glicosilados: engeletina, isoengeletina, astilbina e isoastilbina. Das folhas de I. sagotiana foram isoladas as diidrochalconas I, II e o dímero 3\',3\"\'-bis-2\', 4\',6\'-triidróxi-4-metoxidiidrochalcona, inédito na literatura, além da afzelina, quercitrina, engeletina e astilbina. Os pericarpos de I. lancifolia Ducke forneceram, após procedimentos cromatográficos, as diidrochalconas I e 2\',4-diidróxi-4\',6\'dimetoxidiidrochalcona, inédita, e três flavonolignóides também inéditos: rel (1\"R,2\"R,3\"S)-3\'-(1\",4\"-di-p-hidroxifenil-2\",3\"-dimetilbutil)-2\',4\'-diidróxi-4,6\'-dimetoxidiidrochalcona (III); rel (1\"R,2\"S,3\"R)-3\'-(1\",4\"-di-p-hidroxifenil-2\",3\"-dimetilbutil)-2\',4\'-diidróxi-4,6\'-dimetoxidiidrochalcona (IV) e 5\'-(1\",4\"-di-p-hidroxifenil-2\",3\"-dimetilbutil)-2\',6\'-diidróxi-4,4\'dimetoxidiidrochalcona. Foram isoladas também três lactonas policetídicas inéditas: (2S,3S,4S)-2-(7-dodecenil)-3-hidróxi-4-metil-butanolido, rel (2S,3R,4S)-2-(7\'-dodecenil)-3-hidróxi-4-metil-butanolido e 2-dodecil-3-hidróxi-4-metil-but-2-enolido, além do tocotrienol 2,8-dimetil-2-(4,8,12-trimetil-3,7,11-tridecatrienil)-6-cromanol e da lignana (8R,TS,8\'S)-4,4\'diidróxi-2,7\'-ciclolignana. Das inflorescências de I. lancifolia foram isolados a diidrochalcona I, os flavonolignóides III e IV, o tocotrienol e o esteróide 3-β-O-β-D-galactopiranosilsitosterol. A elucidação estrutural das substâncias isoladas foi baseada em métodos espectrométricos: EM, RMN de 1H e 13C (PND e DEPT 135°), técnicas de RMN bidimensionais (HOMOCOSY e HETERO-COSY) e experimentos para a observação de NOE. Reações de acetilação e epoxidação foram efetuadas para se obterem derivados mais informativos. As atividades antioxidantes da afzelina, da quercitrina, do flavonolignóide IV e do tocotrienol foram avaliadas em comparação com a atividade antioxidante da vitamina E, empregando-se a inibição da autooxidação de homogenato de cérebro como modelo experimental. A capacidade antioxidante foi medida pela produção de malonildialdeído (MDA) e a concentração necessária para inibir 50% da autoxidação (Ql/2) foi calculada. Os valores de Ql/2 obtidos para afzelina, quercitrina, flavonolignóide, tocotrienol e vitamina E foram, respectivamente: 62,30; 2,29; 4,83; 1,08 e 11,20 µM. Estes ensaios foram realizados pela pesquisadora Dra. Solange C. Davino e pela professora Dra. Sílvia B. M. Barros, da Faculdade de Ciências FarmacêutIcas da USP.This work describes the isolation, identification and structural elucidation of chemical constituents from inflorescences and leaves of Iryanthera sagotiana (Myristicaceae) and from inflorescences and pericarps of I. lancifolia, collected in Amazon region. After extraction and partition with organic solvents and chromatographic fractionation, phytochemical analysis of inflorescences of I. sagotiana (Benth.) Warb. afforded four dihydrochalcones: 2\',4\'-dihydroxy-4,6\'dimethoxydihydrochalcone (I); 2\',4\',6\'-trihydroxy-4-methoxy-dihydrochalcone; and the new 2\',4,4\'-trihydroxy-6\'-methoxy-dihydrochalcone (II) and 2\',4\'-dihydroxy- 4-methoxy-6\'-glucopyranosyl-dihydrochalcone. Benzaldehyde, dihydro-p-cumaric acid besides two glycosylated flavonols: afzelin and quercitrin and four glycosylated flavanonols: engeletin, isoengeletin, astilbin and isoastilbin were also isolated and identified. Leaves of I. sagotiana yielded dihydrochalcones I, II and the new dimer 3\',3\"\'-bis-2\',4\',6\'-trihydroxy-4-methoxydihydrochalcone in addition to afzelin, quercitrin, engeletin and astilbin. Pericarps of I. lancifolia Ducke afforded, after fractionation procedures, dihydrochalcones I e 2\',4-dihydroxy-4\',6\'-dimethoxy-dihydrochalcone, which has not been reported in literature yet, as well as three new flavonolignoids: rel (1\"R,2\"R,3\"S)-3\'-(1\",4\"-di-p-hydroxyphenyl-2\",3\"dimethylbutyl)-2\',4\'-dihydroxy-4,6\'-dimethoxydihydrochalcone (III); rel (1\"R,2\"S,3\"R)-3\'-(1\",4\"-di-p-hydroxyphenyl-2\",3\"-dimethylbutyl)-2\',4\'-dihydroxy-4,6\'-dimethoxydihydrochalcone (IV) e 5\'-(1\",4\"-di-p-hydroxyphenyl-2\",3\"dimethylbutyl)-2\',6\'-dihydroxy-4,4\'-dimethoxy-dihydrochalcone. Three new polyketide lactones were also isolated: (2S,3S,4S)-2-(7-dodecenyl)-3-hydroxy-4-methyl-butanolide, rel (2S,3R,4S)-2-(7\'-dodecenyl)-3-hydroxy-4-methylbutanolide e 2-dodecyl-3-hydroxy-4-methyl-but-2-enolide, besides tocotrienol 2,8-dimethyl-2-(4,8,12-trimethyl-3,7,11-tridecatrienyl)-6-cromanol and lignan (8R,T\'S,8\'S)-4,4\'-dihydroxy-2, 7\'-cyclo1ignan. From inflorescences of I. lancifolia, dihydrochalcone I, flavonolignoids III e IV, tocotrienol and the steroid 3-β-O-β-D-galactopyranosylsitosterol were isolated. Structural elucidation of the isolated compounds were based on spectrometric methods: MS, 1H and 13C NMR (PND and DEPT 135°), bidimensional NMR techniques (HOMOCOSY e HETERO-COSY) as well as NOE experiments. Acetylation and epoxidation reactions were carried out in order to get more informative derivatives. Antioxidant activities of afzelin, quercitrin, flavonolignoid IV and tocotrienol were evaluated in comparison with the antioxidant activity of vitamin E, using the inhibition of autoxidation of brain homogenates as a experimental model. The antioxidant capacity was measured by malondialdehyde (MDA) production and the necessary concentration to inhibit 50% of autoxidation (Q12) was calculated. The following values of Q1/2 were obtained for afzelin, quercitrin, flavonolignoid, tocotrienol and vitamin E, respectively: 62,30; 2,29; 4,83; 1,08 e 11,20 µM.
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Meyenberg, Alexander. "Tocotrienol inhibits proliferation of human Tenon's fibroblasts in vitro : a comparative study with vitamin E forms and mitomycin C /". [S.l.] : [s.n.], 2005. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Kim, Hyun Jung. "Oxidation mechanism of riboflavin destruction and antioxidant mechanism of tocotrienols". Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1184681773.
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Fobi, Kwabena. "Purity Optimization of D-Gamma-Tocotrienol from Palm Oil. A Promising Radiation Protective Agent for Treatment of Acute Radiation Syndrome". Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/etd/3739.
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D-γ-tocotrienol (G-T3) chiefly present in palm oil has stolen the spotlight as a promising radiation protective agent for the treatment of acute radiation syndrome (ARS). Although G-T3 is a promising counteracting agent discovered, the separation and purification from its matrix are painstaking. These have limited its characterization, derivatization, and biomedical application. In this study, we developed chromatographic and distillation methods to enhance the purity and synthesis of G-T3 derivatives. Exactly 8% ethyl acetate (EA) in hexanes used in TLC resulted in right spots separation. Two gradient column chromatographic methods were examined using solvent mixtures of EA/hexanes and EA/petroleum ether (PE), respectively. We verified that a gradient elution with EA in PE led to the maximum purity (≥95%) based on the NMR and GC-MS outcomes. Also, G-T3 was stable in an emulsion to some extent, and some soluble G-T3 derivatives were synthesized, and their structure was confirmed
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Ghanegaonkar, Shashank [Verfasser], i Georg [Akademischer Betreuer] Sprenger. "Heterologous biosynthesis of 2-methyl-6-geranylgeranyl benzoquinone and δ-tocotrienol in recombinant Escherichia coli strains / Shashank Ghanegaonkar. Betreuer: Georg Sprenger". Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2014. http://d-nb.info/1048048160/34.
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Rudder, Brittney. "The Effects of the Vitamin E Isomers Gamma Tocopherol and Gamma Tocotrienol on the NFkB Pathway in the PC-3 Cell Line". Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/honors/20.
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Regions along the Mediterranean and Southern Asia have lower prostate cancer incidence compared to the rest of the world. It has been hypothesized that one of the potential contributing factors for this low incidence includes a higher intake of vitamin E (tocopherols and tocotrienols). This study examines the potential of gamma tocopherol (GT) and gamma tocotrienol (GT3) to reduce prostate cancer proliferation by examining their effects on the NFκB pathway. NFκB is known to inhibit apoptosis in cancer cells. Our data shows that both GT and GT3 are capable of down regulation of NFκB precursors and up regulation of Caspase 8, indicating an induction of apoptosis.
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Dave, Havya. "Effects Of Vitamin E Isomer, Gamma Tocotrienol (GT3), At Inhibiting Cell Growth And Inducing Apoptosis In Colon Cancer Cell Line HCT-116". Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/honors/128.
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Colorectal cancer is the third most prominent cancer world-wide and it is the second leading cause of cancer deaths in the United States. Many dietary components affect the risk of developing colorectal cancer, such as Vitamin E. Of the eight isomers of Vitamin E, four have a tocotrienol structure. Tocotrienols are found at highest concentrations in palm oil, which is ingested more in areas of Asia where the incidence of colorectal cancer is the lowest, suggesting a role of tocotrienols in the prevention of colorectal cancer. The metabolism of Arachidonic acid pathway produces a host of pro-inflammatory metabolites either by the Cyclooxygenase (Cox) pathway or the Lipoxygenase (Lox) pathway. The expression of Lox is increased in various human cancer lines; this over expression has been associated with tumor cell proliferation, resistance to apoptosis, and angiogenesis. Another important pathway related to cancer involves mTOR (mammalian target of rapamycin), which is involved in cell growth and human tumorigenesis. The focus of this study included treatment of the HCT-116 colon cancer cell line with gamma tocotrienol to examine potential pathways involved in the induction of apoptosis. Also, whether the Vitamin E-mediated signaling through Arachidonic acid metabolism is necessary for the down regulation of protein translation in the mTOR pathway by using chemical inhibitors specific to Arachidonic acid in the presence and absence of vitamin E treatment was explored. The colon cancer cell line, HCT-116, was treated with gamma tocotrienol isomer and then isolated at 18 and 24 hours. Cells lysates were analyzed by Western Blotting. Our data shows that the mTOR pathway is downregulated by treatment with gamma tocotrienol at 18 hours and 14 hours for 5 µM demonstrating that protein translation is abrogated. Phospho S6 ribosomal protein and phospho-p70 S6 kinase are both downregulated, and phospho-4EBP1 is up regulated upon treatment of gamma tocotrienol. Furthermore, at the same concentrations, Caspase 12 and Caspase 8 are cleaved indicating apoptosis. In addition, parallel up-regulation of 15-LOX-1 and down regulation of Cox-2 at 5 µM at 18 hours is observed. Upon treatment with Caffeic acid, 15-lox-1 is over expressed causing mTOR trend to reverse and down regulation of ERK. Thus, mTOR regulation is dependent on a delicate balance of fatty acid metabolites.
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Luk, Sze-ue, i 陸施妤. "The potential effect of bioactive food supplements in targeting prostate cancer stem cells". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43223795.
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Moraes, Moysés Naves de 1982. "Extração de tocotrienol de sementes de urucum (Bixa orellana L) por extração supercrítica em operação pseudocontínua integrada à extração com solvente a baixa pressão para obtenção de bixina". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254903.
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Orientador: Maria Angela de Almeida MeirelesTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: A busca por produtos naturais que apresentem elevado grau de pureza tem impulsionado pesquisas por processos de extração e, preferencialmente, que não agridam o meio ambiente. Assim, processos de extração com fluido supercrítico (SFE ¿ Supercritical Fluid Extraction) vêm ganhando espaço por propiciar extratos diferenciados. O resíduo obtido da SFE é a matriz sólida livre do extrato de interesse, sendo que esse resíduo pode ser utilizado como matéria-prima em outros processos. Atualmente há grande interesse também em processos que utilizem integralmente a matéria-prima, minimizando a produção de resíduo, e garantindo uma produção mais diversificada oriunda de uma mesma matéria-prima, mas não se pode desconsiderar o processo industrial, e para isso, é necessário desenvolver processos que possam ser integrados sem perder a continuidade da produção, mesmo que o processo, por definição, seja intitulado pseudocontínuo. Para a implementação da SFE em escala industrial uma opção é a operação pseudocontínua de extração com CO2 supercrítico (ScCO2), para que isso seja possível é necessário que a unidade de extração possua no mínimo n+1 extratores, tal que n seja um número inteiro positivo. Então, neste trabalho foi estudada a obtenção de dois tipos de extratos em operação pseudocontínua: (1) óleo volátil de cravo-da-índia, para a validação do processo de extração em modo pseudocontínuo e (2) extrato rico em tocotrienóis de sementes de urucum. Nos dois casos as matrizes vegetais após a SFE podem ser utilizadas para obtenção de outros produtos. No caso do urucum, as sementes desengorduradas possuem grande quantidade de bixina, a qual tem grande aceitabilidade no mercado devido ao seu poder corante, e por isso, utilizou-se esse resíduo como matéria-prima para a obtenção de bixina, promovendo, uma integração de processo. Ademais, o resíduo da extração da bixina e o material lignocelulósico obtido após a SFE do cravo-da-índia podem ser hidrolisados a alta pressão catalisada ou não por CO2 para produzir biopolímeros úteis para serem utilizados na fabricação de nanoestruturas porosas. Para que o processo pseudocontínuo pudesse ser desenvolvido foi necessário o conhecimento atual da área supercrítica, principalmente a nível regional (América Latina e Brasil), além da necessidade de entender as limitações que as diferentes técnicas de extração apresentam para as diferentes classes de compostos de interesse. Então o processo de extração pseudocontínuo foi avaliado, e se mostrou eficaz, permitindo aproveitamento do tempo, pois durante o período de carga e descarga de um leito extrativo o outro estava em período de extração. Deste modo, houve a manutenção de ao menos um extrator em período de extração, caracterizando-se assim a operação pseudocontínua. A extração pseudocontínua do óleo de cravo-da-índia apresentou uma taxa média 3,6 vezes maior que o processo em batelada. A manutenção da razão S/F e do tempo de extração iguais pode ser usada satisfatoriamente para mudança de escala para o cravo e o urucum, ao se utilizar extratores de relação Hb/Db distintas. Por fim, a composição química do óleo de cravo-da-índia foi distinta, sendo então aconselhado uma avaliação prévia dessa composição química antes de definir qual a relação Hb/Db será utilizada
Abstract: The demand for natural products with high purity is promoting studies focused on extraction processes that avoid environmental damages. Supercritical fluid extraction (SFE) processes are gaining emphasis because they afford the extraction of selective compounds when compared with conventional techniques. The residue from SFE is the solid matrix free of target compounds; this residue can be a raw material in other processes. Recently, the appeal for green technologies and the searching for integral use of raw materials are receiving attention. These green technologies minimize the residue generation and promote a diversified production of bioactive compounds from the same raw material. Regarding the industrial scale, integrated processes with continuous productive lines are needed, even that in some cases the processes are named pseudo continuous. Thus, the pseudo continuous extraction using supercritical CO2 (ScCO2) is an important issue for implementing SFE processes in industrial scales. To make it possible, the extraction equipment needs to contain at least n+1 extractors, where n should be a positive integer number. Based on these aspects, we performed in this study the pseudo continuous extraction of two classes of compounds: (1) volatile oil from clove buds for validating the process and (2) tocotrienol rich-extracts from annatto seeds. In both cases the material from SFE can be used to obtain other products. Defatted annatto seeds contain bixin, a coloring pigment that finds several applications. Then, we selected annatto to obtain bixin by using process integration. Furthermore, the residue from the extraction of bixin and the lignocellulosic fraction from the extraction of clove compounds can be hydrolyzed applying high pressure. The reaction can be catalyzed with CO2 to produce biopolymers useful for manufacturing porous nanostructures. To become the pseudo continuous process feasible, we evaluated the information available on the scientific community, especially in Latin America and Brazil. With this search, we could find some limitations about extracting different classes of compounds. Then, we performed the proposed operation, and it yielded good results with respect to optimizing the time. While one bed was in extraction step, the other was in charge/discharge step, characterizing the pseudo continuous extraction mode. In this case, at least one bed was maintained in extraction step along the time. The pseudo continuous extraction of clove oil presented an extraction rate 3.6-fold higher when compared with batch extraction. Besides, process scale up using the studied raw materials might be accomplished by maintaining the S/F ratio equal (for a fixed time) in different Hb/Db ratios. Finally, we observed significant difference (5 % of probability) in the chemical composition of clove oil obtained in both extractors. An evaluation of the oil composition is needed to define the suitable Hb/Db ratio for extraction processes
Doutorado
Engenharia de Alimentos
Doutor em Engenharia de Alimentos
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Borketey, Martha A. "Effects of Select Vitamin E Isoforms on the Production of Polyunsaturated Fatty Acid Metabolites in Colorectal Cancer". Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etd/2480.
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Vitamin E exhibits anti-tumor activity by regulating pathways in cancer cells, potentially the lipoxygenase (LOX) pathway. We studied the effects of alpha tocopherol (AT), gamma tocopherol (GT), gamma tocotrienol (GT3), and an alpha-gamma tocopherol mixture (ATGT) on the production of the LOX metabolites 13-hydroxyoctadecaenoic acid (HODE), 15-hydroxyeicosatetraenoic acid (HETE), 12-HETE, and 5-HETE in colorectal cancer. These metabolites were examined in the HCT-116 cell line after 24 h treatment with select vitamin E isoforms and quantified by LC/MS/MS. Under physiological conditions, we find that treatment with varying vitamin E isoforms have different effects on the production of 13-HODE, 15-HETE, 12-HETE, and 5-HETE. GT increases 13-HODE and decreases 12-HETE. AT reverses the effects of GT regulation on the LOX pathway, while GT3 has no significant effect on the metabolites tested. GT shows superiority in regulating the LOX pathway as it increases 13-HODE and decreases 12-HETE for possible prevention of colorectal cancer.
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Cibulcová, Pavla. "Sledování obsahu vitaminu E ve vzorcích obilovin". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-295687.
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Thesis deals with the analysis of vitamin E in cereal samples, namely barley and wheat and malt produced from them. Selected samples were treated with low-temperature plasma, fungicide and biological treatment to elimination fungus and mycotoxins. The aim of the thesis was to find out the influence of the treatment, the combination of several types of treatment on vitamin E content in grain and malt. If the content of health-positive substances is not reduced and grain can be used for food, malt, or for feed purposes. The theoretical part focuses on the properties, occurrence, biochemistry and importance of vitamin E for living organisms. It also focuses on the properties of cereals that are a significant source of vitamin E. Malt production and sample treatment are also described. The experimental part describes the field experiment, individual types of treatment, extraction of vitamin E from the samples and determination of vitamin E content by high performance liquid chromatography with fluorescence detection. The results are compared with the current literature. It was found that the treatment did not have a significant negative effect on vitamin E content.
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Rink, Cameron L. "Nutritional Intervention And Modeling Of Acute Ischemic Stroke". The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1210957018.
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Drotleff, Astrid M. "Analyse der RS, cis-trans-Tocotrienole". [S.l. : s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=956303374.
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Pfluger, Paul Thomas. "Der Metabolismus der Tocopherole und Tocotrienole". Phd thesis, kostenfrei, 2007. http://opus.kobv.de/ubp/volltexte/2008/1601/.
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Clarke, Michael William. "Vitamin E metabolism in humans". University of Western Australia. School of Medicine and Pharmacology, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0191.
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[Truncated abstract] Vitamin E is comprised of a family of tocopherols (TOH) and tocotrienols. The most studied of these is [alpha]-tocopherol ([alpha]-TOH), as this form is retained within the body and any deficiency of vitamin E is corrected with this supplement. [alpha]-TOH is a lipid-soluble antioxidant required for the preservation of cell membranes and potentially acts as a defense against oxidative stress. Individuals who have a primary vitamin E deficiency such as low birth weight infants, secondary vitamin E deficiency due to fat malabsorption such as in abetalipoproteinaemia, or a genetic defect in TOH transport require supplementation. There is debate as to whether vitamin E supplementation in other patient groups is required. Vitamin E supplementation has been recommended for persons with FHBL, a rare disorder of lipoprotein metabolism that leads to low serum [alpha]-TOH and decreased LDL cholesterol and apolipoprotein B concentrations. We examined the effect of truncated apoB variants on vitamin E metabolism and oxidative stress in persons with heterozygous FHBL. We used HPLC with electrochemical detection to measure [alpha]- and [gamma]-TOH in serum, erythrocytes, and platelets, and GC-MS to measure urinary F2-isoprostanes and TOH metabolites as markers of oxidative stress and TOH intake, respectively. Erythrocyte [alpha]-TOH was decreased, but we observed no differences in lipid-adjusted serum TOHs, erythrocyte [gamma]-TOH, platelet [alpha]- or [gamma]-TOH, urinary F2-isoprostanes, or TOH metabolites. Taken together, our findings do not support the recommendation that persons with heterozygous FHBL should receive vitamin E supplementation. ... Sesame lignans are natural components of sesame seed oil and there is evidence that these lignans can inhibit CYP450 enzymes, in particular, those responsible for vitamin E metabolism. We hypothesised that sesame seed ingestion would increase serum [gamma]-TOH, lower plasma lipids and inhibit platelet function in human subjects with at least one cardiovascular risk factor. We used HPLC with electrochemical detection to measure [alpha]- and -TOH in serum and GC-MS to measure F2-isoprostanes and TOH metabolites as markers of oxidative stress and TOH intake, respectively. We used high-sensitive C-reactive protein as a measure of systemic inflammation. Platelet function was assessed using the PFA-100 platelet aggregation assay. Although serum [gamma]-TOH increased by 17%, we observed no effect on lipid metabolism, markers of inflammation, oxidative stress or platelet function following treatment with ~25 g/day sesame seeds for five weeks. Our findings challenge the hypothesis that sesame seed ingestion provides beneficial cardiovascular effects. In summary, we have studied the metabolism and transport of both [alpha]- and [gamma]-TOH in humans to evaluate the requirements for supplementation and the effects of vitamin E on platelet function and CYP3A4 activity. Specialised techniques using HPLC were developed to measure serum and cellular TOH concentrations both in supplemented and un-supplemented individuals. We also used GCMS to provide a sensitive, accurate assessment of TOH metabolites and midazolam pharmacokinetics in humans after vitamin E supplementation. We have examined the role vitamin E has on important biochemical endpoints, with emphasis on the implications for TOH supplementation in subjects at risk of CVD.
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Landes, Nico. "Vitamin E : elucidation of the mechanism of side chain degradation and gene regulatory functions". Phd thesis, [S.l. : s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=975679473.
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Luna, Cornadó Jeroni. "Eficàcia dels tocotrienols com a estratègia de tractament de la fibrosi intestinal". Doctoral thesis, Universitat de Barcelona, 2011. http://hdl.handle.net/10803/83361.
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En el patró fibroestenosant de la malaltia de Crohn els fibroblasts intestinals augmenten en número contribuint al desenvolupament de la fibrosi. Un dels principals promotors de la proliferació d’aquestes cèl•lules és el bFGF. En el present estudi la fracció rica en tocotrienol ha demostrat tenir efectes antiproliferatius en fibroblasts intestinals humans independentment de la procedència dels fibroblasts. Els tocotrienols redueixen tant la proliferació basal com la induïda per bFGF en fibroblasts.
L’apoptosi de les cèl•lules efectores en el desenvolupament de la fibrosi sembla ser el principal mecanisme de la seva resolució. Els tocotrienols instauraren un procés complert d’apoptosi en els fibroblasts. A diferència del que passa amb la majoria d’agents proapoptòtics, els tocotrienols provoquen l’activació tant de la via extrínseca com de la via intrínseca de l’apoptosi ja que activa les caspases 8 i 9.
Sorprenentment, l’addició de ciclosporina A (CsA), un conegut inhibidor de la via intrínseca de l’apoptosi, bloqueja completament el procés d’apoptosi induït per FRT. Això demostra que tot i l’activació de la caspasa 8 i per tant, de la via extrínseca, en el tractament amb tocotrienols la predominant és la via intrínseca.
L’autofàgia té un paper molt rellevant en l’aclariment de cossos apoptòtics. Els tocotrienols han demostrat eficàcia en la inducció d’autofàgia en fibroblasts, ja que provoca la maduració de la proteïna LC3 i l’aparició de vacuoles autofàgiques en el citoplasma d’aquestes cèl•lules. Un cop més la CsA reverteix aquest procés, i per tant inhibeix l’autofàgia, demostrant que aquest procés requereix la participació de la mitocòndria.
Les patologies que cursen amb desenvolupament de fibrosi estan associades a alts nivells de TGF-β que resulta en el reclutament de fibroblasts al lloc de la lesió i a un increment en la producció de matriu extracel•lular. A nivell intracel•lular, la fosforilació d’Smad3 és el pas clau que regula les accions del TGF-β. Els tocotrienols han mostrat eficàcia en la disminució dels nivells intracel•lulars d’Smad3 fosforilada induïda per TGF-β.
La fosforilació d’Smad3 té efectes oposats en la regulació de l’expressió gènica. Regula positivament l’expressió de TIMP-1, en canvi, regula negativament l’expressió de MMP-3. Tot i ser efectes oposats en quant a expressió gènica, aquests dos fenòmens afavoreixen l’acumulació de matriu extracel•lular. L’exposició a tocotrienols fa que es reverteixi aquest estat profibrogènic ja que indueix l’expressió de MMP-3 però no afecta als nivells de TIMP-1.
La síntesi de MEC i especialment la síntesi de COL1, COL3 i COL5 està incrementada en la fibrosi intestinal, aquest fet està directament relacionat amb l’activitat de TGF-β en la zona afectada. Els tocotrienols interfereixen en la síntesi de col•lagen.
A més, els tocotrienols disminueixen la fosforilació d’Smad3 induïda per TGF-β, un fet clau en la síntesi de matriu extracel•lular.
Aquests resultats permeten hipotetitzar un potencial antifibrogènic dels tocotrienols. Per a confirmar aquest potencial “in vivo” ens calia disposar d’un model experimental de fibrosi intestinal. A diferència del que succeeix amb la colitis, en la que es disposa d’un gran nombre de models animals, hi ha pocs models experimentals específicament dissenyats per a reproduir la fibrosi intestinal. Aquest fet, ha limitat molt el desenvolupament de noves estratègies de tractament antifibrogènic en l’intestí.
Mitjançant l’administració intracolònica repetida a dosis baixes de l’haptè TNBS vam poder establir fibrosi intestinal en la rata de manera rellevant i reproduïble.
En aquest model de fibrosi intestinal, els animals que van rebre la dosi més alta de tocotrienols provada en aquest estudi van mostrar nivells disminuïts en paràmetres que mesuren la inflamació, això és, es va disminuir l’índex d’activitat de la malaltia i la pèrdua de pes causada pel TNBS així com també va reduir l’expressió de TNF-α.Excessive fibroblast expansion and extracellular matrix deposition are key events for the development of bowel stenosis in Crohn’s disease patients. Tocotrienols are vitamin E compounds with proven in vitro antifibrogenic effects on rat pancreatic fibroblasts. We aimed at investigating the effects of tocotrienols on human intestinal fibroblast proliferation, apoptosis, autophagy, and synthesis of ECM. Intestinal fibroblasts isolated from patients with Crohn’s disease were treated with tocotrienol-rich fraction from palm oil. Tocotrienols significantly reduced proliferation, enhanced cell death by promoting apoptosis and autophagy. Fibroblast apoptosis, but not autophagy, was prevented by the pan-caspase inhibitor zVAD-fmk, whereas both types of cell death were prevented when the mitochondrial permeability transition pore was blocked by cyclosporin A, demonstrating a key role of the mitochondria in these processes. TRF diminished procollagen type I and laminin γ production these cells. Transforming growth factor-β plays a key role in matrix deposition during fibrosis. Treatment of intestinal fibroblasts with tocotrienol rich fraction prevents Smad3 phosporylation induced by transforming growth factor-β and reduces collagen type 1 and 3 production by these cells. Besides, in a rat model of intestinal fibrosis, treatment with tocotrienols reduces diarrhea, rectal bleeding and weight loss, as well as levels of colonic tumor necrosis factor-α and vimentin expression demonstrating that this compound has anti-inflammatory effects in vivo.
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Zuo, Tianming. "The In Vitro Cellular Uptake and Physiochemical Properties of Tocotrienols". [Johnson City, Tenn. : East Tennessee State University], 2003. https://dc.etsu.edu/etd/780.
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Thesis (M.S.)--East Tennessee State University, 2003.Title from electronic t.p. ETSU ETD database URN: etd-0618103-114702. Includes bibliographical references. Also available via Internet at the UMI web site.
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Drotleff, Astrid Marlene [Verfasser]. "Analytik funktioneller Inhaltsstoffe (Tocotrienole und Eigelbproteine) in Nebenprodukten der Lebensmittelverarbeitung / Astrid Marlene Drotleff". Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2017. http://d-nb.info/1123650810/34.
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Walde, Constanze [Verfasser]. "Biotransfer von Tocotrienolen aus Gersten- und Palmöl ins Hühnerei: Biotransferraten, Einfluss der Emulsionsbildung und Effekte auf die Cholesterolgehalte im Ei und Blutserum / Constanze Walde". Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2013. http://d-nb.info/1046851535/34.
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Cuevas, Espinal Mery Milagros, i Julián Natividad Roxana Lozano. "Actividad antioxidante y composición de ácidos grasos, tocoferoles y tocotrienoles en tres variedades de Chenopodium quinoa Willdenow y elaboración de una crema dermocosmética antienvejecimiento". Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2017. https://hdl.handle.net/20.500.12672/7113.
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Extrae los aceites de tres variedades de Chenopodium quinoa Willd. (quinua blanca, roja y negra) y analiza su efecto antioxidante por los métodos 2,2-difenil-1-picrilhidrazil (DPPH) y ácido 2,2’-azinobis (3-etilbenzotiazolin)-6-sulfónico (ABTS•+), in vitro. Posterior a la extracción elabora una crema dermocosmética con los aceites y comprueba su efecto antienvejecimiento, envejecimiento provocado por la radiación UVA y UVB, in vivo. Los aceites extraídos son analizados por Cromatografía de Gases (CG) y Cromatografía Líquida de Alta Presión y Polaridad (HPLC) para determinar ácidos grasos y tocoferoles/tocotrienoles respectivamente. En el análisis por DPPH, los aceites muestran una actividad antioxidante con IC50 de 3 587; 2 576 y 3 316 μg/mL para quinua blanca, roja y negra respectivamente; en el análisis por ABTS•+ se obtiene el valor TEAC 28,362; 29,176 y 31,351 mg Trolox/g muestra para quinua blanca, roja y negra respectivamente. Se elaboran las cremas dermocosméticas antienvejecimiento a tres concentraciones (3, 6 y 9 %) con cada tipo de aceite y se evalúan los aspectos fisicoquímicos y microbiológicos. La piel de los ratones es evaluada de forma histológica, in vivo, para comprobar el efecto antienvejecimiento. Se concluye que la crema con aceite de quinua roja presenta mejor efecto antienvejecimiento, seguida de la quinua negra y blanca, además este efecto mejora conforme se aumenta la concentración del aceite en la crema.Tesis
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Barrales, Francisco Manuel 1986. "Extração de óleo de semente de maracujá (Passiflora edulis sp.) usando CO2 supercrítico assistido por ultrassom". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254630.
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Orientador: Julian MartínezDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O presente trabalho teve como principal objetivo avaliar a influência da aplicação de ultrassom na extração de óleo de semente de maracujá com CO2 supercrítico, focando no rendimento da extração, na cinética do processo, conteúdo de tocoferóis e tocotrienóis, perfil de ácidos graxos, e atividade sequestrante do radical DPPH do óleo, usando como matéria-prima sementes de maracujá misturadas com polpa provenientes da indústria de processamento da fruta. Com esse intuito, a metodologia de superfície de resposta foi empregada, partindo como base de um planejamento experimental de tipo composto central para três fatores. Os fatores avaliados foram temperatura (38; 40; 45; 50 e 52°C), pressão (13; 16; 21; 26 e 29 MPa) e potência de ultrassom (0; 160; 400; 640 e 800 W). Os extratos obtidos apresentaram alto porcentagem de ácidos graxos poli-insaturados (aproximadamente 67%) e teor de tocoferóis e tocotrienóis (entre 60 e 90 mg/100g óleo), atividade sequestrante do radical DPPH (entre 1,8 e 2,6 mg TE/g óleo) que demonstrou correlação com o conteúdo total de tocoferóis e tocotrienóis (r = +0,872). A análise de polifenóis totais não conseguiu detectar a presença de polifenóis nos extratos. A aplicação de ultrassom na menor potência (160 W) resultou vantajosa, gerando incrementos de até 29% no rendimento de SFE. Este efeito foi registrado na temperatura de 40 °C e pressão de 16 MPa. O modelo de Sovová (1994) mostrou-se adequado para descrever o comportamento da cinética de extração, permitindo avaliar os parâmetros ajustados. Quando foi evidenciado grande incremento no rendimento da SFE, decorrente da aplicação do ultrassom, os parâmetros cinéticos foram modificados, sendo o tempo da etapa CER maior, junto com o coeficiente de transferência de massa da fase fluida, houve diminuição da proporção de extrato de difícil acesso. As imagens obtidas por microscopia eletrônica de varredura com fonte de emissão de campo (FESEM) demonstraram efeitos de atrito e menor tamanho de partículas quando o ultrassom foi aplicado
Abstract: The present work had as main objective the evaluation of the effect of the application of ultrasound in the extraction of passion fruit seed oil using supercritical CO2, on the global extraction yield, the process kinetics, the tocopherol and tocotrienol content and DPPH radical scavenging activity, using as raw material passion fruit seeds mixed with pulp, a byproduct of the pulp processing industry. To accomplish that, the response surface methodology was used. The evaluated factors were: temperature (38; 40; 45; 50 and 52 °C), pressure (13; 16; 21; 26 and 29 MPa) and ultrasound power (0; 160; 640 and 800 W). Fatty acids composition, total polyphenolic content, identification and quantification of tocopherols and tocotrienols and the antioxidant activity were evaluated on the extracts, which resulted rich in polyunsaturated fatty acids (about 67%) and tocopherols and tocotrienols (between 60 and 90 mg/100g oil), of high antioxidant activity (between 1,8 to 2,6 mgTE/g oil) that shown correlation with the tocopherol and tocotrienol total content (r = +0,872). The total polyphenol analysis was not able to detect the presence of polyphenols in the extracts. The application of low power ultrasound (160 W) resulted advantageous; the SFE global yield improvement achieved 29%. This effect was registered at a temperature of 40 °C and pressure of 16 MPa. The model of Sovová (1994) was adequate to describe the extraction kinetics behavior, and it was possible to evaluate the adjusted parameters. When a great increase of SFE yield was achieved due to the ultrasound application, the kinetic parameters were modified, being the CER time and the fluid phase mass transfer coefficient increased, also showing reduction of solute ratio inside the cells. . The images obtained by field emission scanning electron microscopy (FESEM) demonstrated mechanical damage effects and smaller particle size when ultrasound was applied
Mestrado
Engenharia de Alimentos
Mestre em Engenharia de Alimentos
33
Irías-Mata, Andrea Paola [Verfasser], i Jan [Akademischer Betreuer] Frank. "Tocotrienols, tocopherols and tocomonoenols : characterization in Costa Rican palm oils, and intracellular and tissue distribution as a function of the hepatic alpha-tocopherol transfer protein / Andrea Paola Irías-Mata ; Betreuer: Jan Frank". Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2019. http://d-nb.info/1182423574/34.
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Irías, Mata Andrea [Verfasser], i Jan [Akademischer Betreuer] Frank. "Tocotrienols, tocopherols and tocomonoenols : characterization in Costa Rican palm oils, and intracellular and tissue distribution as a function of the hepatic alpha-tocopherol transfer protein / Andrea Paola Irías-Mata ; Betreuer: Jan Frank". Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2019. http://d-nb.info/1182423574/34.
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Ansolin, Marina 1987. "Determinação de dados experimentais de equilíbrio líquido-líquido de sistemas graxos com ênfase na distribuição de tocoferóis e tocotrienóis". [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256194.
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Orientador: Eduardo Augusto Caldas BatistaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Os óleos vegetais, em sua grande maioria, quando destinados ao consumo humano necessitam passar pelas etapas de refino, visando à retirada de substâncias indesejáveis. Das etapas do refino, a desacidificação ou retirada de ácidos graxos livres é a mais importante e normalmente é realizada pelo método químico ou físico. Uma alternativa para a desacidificação é a extração líquido-líquido ou refino com solvente. Nesse processo ocorrem reduções significativas de perda de óleo neutro, além de ser conduzida à temperatura ambiente e pressão atmosférica, reduzindo custos energéticos. O óleo vegetal resultante apresenta teores aceitáveis de ácidos graxos livres, sabor e odor brando e redução das perdas de compostos minoritários desejáveis como os tocoferóis e tocotrienóis (tocóis), que são antioxidantes naturais presentes nos óleos vegetais. Com base no exposto, o objetivo desse trabalho é a determinação de dados experimentais de equilíbrio líquido-líquido de sistemas graxos, com ênfase na distribuição de tocoferóis e tocotrienóis. Os sistemas graxos estudados foram óleo de soja degomado + ácido linoléico comercial + etanol anidro, óleo de soja degomado + ácido linoléico comercial + etanol + água, óleo de farelo de arroz + ácido oléico comercial + etanol anidro e óleo de farelo de arroz refinado + ácido oléico comercial + etanol + água. Os experimentos foram realizados nas temperaturas de 298,15 K, 313,15 K e 323,15 K. A partir dos resultados obtidos, verificou-se que a solubilidade mútua do óleo vegetal + solvente (etanol anidro ou etanol + água) e o coeficiente de distribuição dos tocóis foram afetados pela temperatura, concentração de ácidos graxos livres e presença de água. Quanto maior a temperatura e teor de ácidos graxos livres, maior o coeficiente de distribuição dos tocóis devido ao aumento da solubilidade entre os componentes do sistema. Em contrapartida, quando adicionado água ao etanol, o coeficiente de distribuição dos tocóis diminui, fazendo com que eles fiquem mais retidos na fase oleosa
Abstract: Vegetable oils, mostly, when for human consumption, need to be refined, with the objective of removal of undesirable substances. Deacidification or free fatty acid removal is the most important step and it is usually performed by physical or chemical method. An alternative to deacidification is the liquid-liquid extraction or solvent refining. In this process, significant reductions of loss of neutral oil occur, and it is conducted at room temperature and atmospheric pressure, reducing energy cost. The resulting vegetable oil has acceptable levels of free fatty acids, mild taste and odor and reduction in the losses of desirable minor compounds, such as tocopherols and tocotrienols (tocols), which are natural antioxidants present in vegetable oils. Based on the exposed, the objective of this study is the determination of experimental data for liquid-liquid equilibrium of fatty systems, with emphasis on the distribution of tocopherols and tocotrienols. The fatty systems studied were composed by degummed soybean oil + commercial linoleic acid + anhydrous ethanol, degummed soybean oil + commercial linoleic acid + ethanol + water, refined rice bran oil + commercial oleic acid + anhydrous ethanol and refined rice bran oil + commercial oleic acid + ethanol + water. The experiments were performed at temperatures of 298.15 K, 313.15 K and 323.15 K. From the results obtained, it was found that the mutual solubility between vegetable oil and solvent (ethanol or ethanol + water) and the distribution coefficients of the tocols were affected by temperature, concentration of free fatty acids and the water presence. The higher the temperature and free fatty acid content, higher the distribution coefficients of tocols, due to the increase of solubility among the components of the systems. In contrast, the distribution coefficients of tocols decrease when water is added to ethanol, which represents the increase in retention of tocols in the oil phase
Mestrado
Engenharia de Alimentos
Mestre em Engenharia de Alimentos
36
Chao, Jun-Tzu. "Modulation of monocyte-endothelium adhesion by tocotrienol". 2001. http://wwwlib.umi.com/dissertations/fullcit/3017390.
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Chatterjee, Debolina. "Tocopherol and tocotrienol content of fast foods and pizzas". 2005. http://purl.galileo.usg.edu/uga%5Fetd/chatterjee%5Fdebolina%5F200505%5Fms.
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Chen, Hsiu-wen, i 陳綉文. "Antimelanogenesis effect of δ-tocotrienol on B16 melanoma cells". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/42401294641524802028.
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碩士嘉南藥理科技大學
營養與保健科技研究所
99
Several studies have shown that tocotrienols displayed the cholesterol lowering effect, antioxidative and anti-cancer activities. The study has not about antimelanogenesis mechanism (s) of δ-tocotrienol. So our study the effects of δT3 on skin-whitening agent and antimelanogenesis mechanism (s) in the first. In this study, our aims were (1) to evaluate the effect of α-, γ-, δ-tocotrienols (αT3, γT3, and δT3), and arbutin on cell viability, (2) to study the effects of δT3 and arbutin on the ROS production, and (3) to examine the effects of δT3 and arbutin on the melanin content, the expression of melanogenesis-related proteins such as tyrosinase, MC1R, Mitf, TRP (-1 and -2) and MAPK pathway in B16 melanoma cells. We found that δT3 possessed the best protective effect in B16 cells. Our data indicated that 20 μM δT3, but not arbutin, significantly decreased the generation of ROS, as a specific inhibitor of melanin production and reduced the expression of tyrosinase, MC1R, Mitf, TRP (-1 and -2) mRNA. Cells treated with δT3, and also markedly up-regulated the activation and phosphorylation of ERK kinases, down-regulated the phosphorylation of p38 kinase, and reduced melanin synthesis. These results suggest that δT3 performed well in both melanogenesis inhibition and antioxidation.
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Xiong, Ailian. "Targeting triple negative human breast cancer with omega-3 docosahexaenoic acid (DHA) and tocotrienol". 2013. http://hdl.handle.net/2152/21529.
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Triple negative breast cancers (TNBCs) account for ~15-20% of human breast cancers in Western countries. TNBCs are associated with poor prognosis and a low five year survival rate due, in part, to high rates of tumor recurrence, multi-drug resistance, metastasis, and therapeutic toxicity. Tumor initiating cells (TICs) or cancer stem cells (CSCs) are proposed to be responsible for the origin and maintenance of tumors as well as cancer recurrence, metastasis and drug resistance. Nutritionally-based low- to non-toxic therapeutic nutrients that eliminate both bulk tumor cells (non-TICs) and TICs have potential for prevention and treatment of primary and metastatic cancers, including TNBCs. Omega-3 fatty acid-docosahexaenoic acid (DHA) and certain vitamin E compounds [gamma- and delta- tocopherols [mathematical symbols] and tocotrienols [mathematical symbols]], separately and in combination, were investigated for their ability to eliminate non-TICs and TICs in human TNBCs and the mechanisms of action were studied. DHA induced apoptosis in several human TNBC cell lines via activation of endoplasmic-reticulum stress (ER stress) mediated C/EBP (CCAAT/enhancer binding protein) homologous protein (CHOP)/death receptor-5 (DR5) pro-apoptotic signaling involving caspases-8 and 9. DHA eliminated TICs as measured by elimination of aldehyde dehydrogenase active (ALDH⁺) population and inhibition of mammosphere formation. DHA eliminated TICs via suppression of phosphorylated Signal transducers and activators of transcription 3 (pStat-3) as well as downstream mediators cellular myelocytomatosis oncogene (c-Myc) and cyclin D1. SiRNA to Stat-3 reduced the number of ALDH⁺ TNBCs cells and reduced pStat-3, c-Myc, and cyclin D1 mediators, showing that Stat-3 is necessary for maintaining ALDH⁺ population and that c-Myc and cyclin D1 are downstream mediators of Stat-3. Studies also demonstrated that vitamin E compounds possess distinct anticancer activities. In summary, studies provide novel insights into therapeutic potential of DHA and certain vitamin E compounds for treatment of TNBCs.text
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Lin, Yi-Huei, i 林怡慧. "Mechanistic studies on the cholesterol synthesis inhibition by gamma-tocotrienol in HepG2 cell model". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/46363600264381249332.
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碩士國立屏東科技大學
生物科技系所
101
HMG-CoA reductase is the rate-controlling enzyme of the mevalonate pathway, the metabolic pathway produces cholesterol. γ-Tocotrienol and farnesol has the similar chemical structure and both of them promote the degradation of HMG-CoA reductase. In this study, human hepatoma HepG2 cell line was used to investigate how γ-tocotrienol inactivate HMG-CoA reductase and reduce the biosynthesis of cholesterol. Red yeast rice contains several compounds collectively known as monacolins, substances known to inhibit cholesterol synthesis as well. One of these, monacolin K is a potent inhibitor of HMG-CoA reductase, and is also known as mevinolin or lovastatin. Western blot assay showed that γ-tocotrienol inhibited HMG-CoA reductase protein expression. γ-Tocotrienol and monacolin K were found to decrease total cholesterol in HepG2 cell in a dose dependent manner. γ-Tocotrienol treatment was found to inhibit the translocation of Ras inactivate in HepG2 cell by using confocal microscopy. Taken together, these data suggest that γ-tocotrienol inhibit isoprenylation, and leading to Ras inactivation, subsequently inhibiting HMG-CoA reductase protein expression, and reducing the biosynthesis of cholesterol.
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(8800832), Chieh-Yu Liu. "VITAMIN E DELTA-TOCOTRIENOL AND METABOLITE: MODULATION OF GUT MICROBIOTA AND CHEMOPREVENTION OF COLORECTAL CANCER". Thesis, 2020.
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Colorectal cancer is one of the leading causes of cancer deaths in the United States and multiple modifiable factors contribute to colorectal carcinogenesis. Gut microbiota are believed to play key roles in colon cancer development. Dietary factors may modulate gut microbiota composition, which may potentially have impact on carcinogenesis. Thus, it is reasonable to develop dietary interventions to effectively prevent colorectal cancer development through alteration of gut microbiota. In this thesis, the first objective is to evaluate the effect of vitamin E forms and metabolites, i.e., δ-tocotrienol (δTE), γ-tocotrienol (γTE) and δTE-13’-COOH (δTE-13’), respectively, on gut microbiota in mice. Healthy male balb/c mice were supplemented with a δTE/γTE mixture or δTE-13’ by gavage for two weeks, while control mice received soybean oil. We isolated DNAs from fecal samples and used 16S rRNA gene sequencing to evaluate the impact of these compounds on gut microbiota compositions. Further, we also examined the effect on short chain fatty acids (SCFAs). We observed that supplementation of δTE-13’ increased microbial richness using the Faith index. On the other hand, supplementation did not separate the microbial communities from the control group. But, these compounds managed to alter the relative abundances of several taxa that might present chemopreventive activities against colon cancer. Specifically, Desulfovibrio, a sulfur-reducing bacterium, was decreased after δTE/γTE supplementation. Eubacterium coprostanoligenes group, a group of microbes that can reduce circulating cholesterol, was increased after δTE/γTE supplementation. In addition, several members from the Lachnospiraceae family were elevated under δTE/γTE and δTE-13’ supplementation, and these microbes are known to produce SCFAs and maintain colonic health. However, the measurement of SCFAs showed that supplementation of δTE/γTE and δTE-13’ did not change SCFAs compared with controls. In the second project, I investigated anti-proliferative effects of combining δTE or δTE-13’ with sodium butyrate (NaBu) on human colorectal carcinoma HCT116 cells. Our data showed promising additive effects against cell growth. Collectively, these results indicate that δTE/γTE and δTE-13’ can modulate gut microbiota under healthy conditions, which provides insights into potential chemopreventive activities of these vitamin E forms. Our cell-based studies also showed additive anticancer effects of combining δTE or δTE-13’ with NaBu, which provides rationale to further develop combination of butyrate producers with vitamin E forms for cancer prevention.
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Lee, Shu-Ping, i 李蜀平. "Evaluation of hepatic protection of tocotrienol rich fraction against CCl4-induced chronic liver injury in rats". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/23894573446934872412.
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碩士高雄醫學大學
藥學研究所碩士在職專班
97
Studies have shown that tocotrienols possess antioxidant, anti-lipid peroxidation, cholesterol lowering, reducing blood coagulating factor thromboxane B2 and anti-cancer activities. In this study, we examined the hepatoprotective effects of palm tocotrienol rich fraction (TRF) against carbon tetrachloride (CCl4) induced chronic liver damage in rats. Study was divided into five groups, namely groups one and two received normal saline without and with CCl4 respectively. Groups three, four and five received silymarin, TRF 25mg/kg (TRF-25), and TRF 50mg/kg (TRF-50) plus CCl4 respectively. Results showed that after 8 weeks of TRF-25 and TRF-50 treatment, TRF significantly reduced TBARS (thiobarbituric acid reactive substances) , ALT (alanine aminotransferase) and AST (aspartate aminotransferase) levels, while increased the blood total antioxidant capacity, superoxidase dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) concentration in CCl4 induced liver injury groups. In addition, total cholesterol (TC), low-density lipoprotein (LDL) were noted to be significantly decreased in the TRF treated groups. These results suggest that TRF can effectively enhanced the antioxidant enzymes and reduced the level of ALT and AST. Taken together, this study concludes that TRF was able to protect liver against CCl4 induced liver injury in rats through enhancing the levels of antioxidant enzymes and decreasing ALT, AST and lipid peroxidation.
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Huang, Guang-Yu, i 黃光裕. "The antiproliferative effect of γ-tocotrienol and its molecularmechanism (s) of action in 3T3-L1 adipocytes". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/70977571060551810028.
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碩士嘉南藥理科技大學
營養與保健科技研究所
99
Tocotrienols of palm oil and rice bran oil have been shown to possess potent anticancer, lower blood pressure and cholesterol-lowering activities. In this study, our aims were (i) to evaluate the antiproliferative activities of α-, γ- and δ-tocotrienols (α-T3, γ-T3, and δ-T3), and α-tocopherol (αT) in 3T3-L1 adipocytes, (ii) to study the effects of γT3 on the cell cycle distribution, ROS production and mitochondrial membrane potential, and (iii) to examine the apoptotic and the adipogenesis molecular mechanism (s) of action in 3T3-L1 cells. The results showed that γ-T3 was the most effective, with an IC50 value of 13.91 ± 0.25 μM. It effectiveness induced the 3T3-L1 cells apoptosis, caused ROS formation, collapse of the mitochondrial membrane potential and cell cycle perturbation (S-phase arrest). At 20 μM, γ-T3 significantly increased the accumulation of the DNA fragmentation. Western blot data revealed that γ-T3 treatment increased the expression of active p53, CD95 (APO-1/CD95), and led to up-regulation of Bax and release cytochrome c from mitochondria to cytosol, as well as causing the caspase-3 activation, and PARP cleavage in a dose- and time-dependent pattern. Furthermore, γ-T3 did not affect the expression of JNK, p-JNK, p38, p-p38 and AMPK proteins, however it down-regulated the Akt, p-Akt, ERK, p-ERK, and PPAR-γ levels and up-regulated the expression of p-AMPK. These results suggest that γ-T3 has contributed to the potent antiproliferative activity and apoptosis in 3T3-L1 adipocytes through the CD95 (APO-1/CD95) system and the mitochondrial signaling transduction pathway.
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Jhu, Chao-Fu, i 朱照夫. "The inhibitory effects of γ -tocotrienol on adipogenesis and lipid accumulation effects and its molecular mechanism (s) of action in 3T3-L1 adipocytes". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/7s58zy.
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碩士嘉南藥理大學
保健營養系
103
Tocotrienols, members of the vitamin E family, are natural compounds only found in certain numbers of plant seeds; for example, wheat and nuts. Tocotrienols exhibit biological activities such as neuroprotective, anti-cancer, anti-inflammatory and cholesterol lowering properties. In this study, our aims were to examine the anti-proliferative and lipid accumulation effects of α-, γ- and δ-tocotrienols (αT3, γT3 and δT3) in 3T3-L1 adipocytes, and to study the energy and adipogenesis molecular mechanism (s) of action in 3T3-L1 cells. The results displayed that 30 μM γT3 was effective in inhibiting the cell proliferation. In addition, γT3 significantly reduced the lipid accumulation effect in 3T3-L1 adipocytes. Western blot data showed that γT3 treatment up-regulated the expression of CD36, Sirt (1and 3), p-AMPK and LXRα proteins, but it down-regulated the expression of ACC, PPAR-γ and FAS. These results have demonstrated that γT3 possesses anti-proliferative and anti-adipogenic effects; its molecular mechanism of action could be through the modulation of the Sirt1, LXRα, p-AMPK and PPAR-γ signaling pathways.
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"Vitamin E (Tocotrienols) and Prostate Cancer: A Proteomics Approach". East Tennessee State University, 2007. http://etd-submit.etsu.edu/etd/theses/available/etd-0710107-152943/.
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"The In Vitro Cellullar Uptake and Physiochemical Properties of Tocotrienols". East Tennessee State University, 2003. http://etd-submit.etsu.edu/etd/theses/available/etd-0618103-114702/.
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Pfluger, Paul Thomas [Verfasser]. "Der Metabolismus der Tocopherole und Tocotrienole / von Paul Thomas Pfluger". 2007. http://d-nb.info/987410156/34.
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Drotleff, Astrid M. [Verfasser]. "Analyse der RS,cis-trans-Tocotrienole / von Astrid M. Drotleff". 1999. http://d-nb.info/956303374/34.
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Chang, Chia-Chen, i 張嘉辰. "Tocotrienols and other allelopathic compounds from leaves of Litchi chinensis". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/zp527b.
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碩士中國醫藥大學
生態暨演化生物學研究所碩士班
101
Litchi (Litchi chinensis Sonn.) is a tropical and subtropical plant with high commercial value. In the field, there are relatively few understory species on the floor of litchi plants. Firstly, litchi leaves contain many natural product, and we have tried to isolate pure compounds in order to develop these compounds to be highly potential as a healthy food. Secondly, it is aiming to understand whether litchi plants may exhibit allelochemical potential. In part one, methanolic extracts of litchi leaves were subjected to column chromatography. Nine new tocotrienols compounds (Litchitocotrienol A~I), and four known compounds (4-hydroxybenzaldehye, procyanidin A2, (-)-epicatechin, 4-hydroxy-3-methoxybisnbola-1,10-diene) were isolated and identified. These compounds exhibit anti-cancer and anti-oxidant activity. The above results of litchi leaves have the high potential to develop as anti-cancer healthy food. In part two of pot experiment the lithci leaves exhibited inhibitory effect on seedling growth of Bidens pilosa during the first 23 days. But the inhibitory effect was disappeared 35 days after. However, the inhibitory effect of leaf powder against B. pilosa was decreased in the sterilized soil, indicating that the sterilized soil might lose the microbial involvement leading the litchi leaves were not be add to degrade the products into allelochemical agent. The alleolchemical, 4-hydroxybenzaldehye, isolated in the litchi leaves exhibited inhibitory effects on radicle growth of B. pilosa at 1 mM in the bioassay. It is concluded that allelochemicals in litchi leaves may involve in the interaction between plants and microbes. Futher studies should clarify the interaction between litchi leaves with soil microorganisms.
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Štůsková, Martina. "Cesta k novým analogům vitamínu E - novým potenciálním inhibitorům 5-lipoxygenázy". Master's thesis, 2019. http://www.nusl.cz/ntk/nusl-404165.
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Many studies highlighted the biological potential of vitamin E, especially tocotrienols (T3), a vitamin E subfamily, particularly in the field of cardiovascular diseases and chronic inflammation. A pharmacophore based virtual screening of these substances against various antiinflammatory targets showed that this class could be considered as potential inhibitors of 5- lipoxygenase, a key enzyme in the biosynthesis of chemoattractant and vasoactive leukotrienes. Consequently, this screening was confirmed by in vitro assays. However, usual natural sources of T3 provide complex mixtures involving particularly challenging purification processes. Thus, this work aims at designing and optimizing efficient semisynthesis towards pharmacologically relevant T3 derivatives were developed from δ- tocotrienol, the main T3 isolated from Bixa orellana seeds, a renewable and easily available vegetal source from tropical regions, analyzed mainly by HPLC chromatography. Verification of the most effective reaction conditions of semisynthesis and synthesis another potential inhibitors of 5-LOX based on tocotrienols' structure are the following aims of the work. During this study, the semisynthesis based on δ-tocotrienol was completely optimized and 3 new T3 derivatives were synthesized and fully characterized....