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S Ratti - One of the best experts on this subject based on the ideXlab platform.
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tocopherols and Tocotrienols as free radical scavengers in refined vegetable oils and their stability during deep fat frying
Food Chemistry, 2007Co-Authors: M Rossi, C Alamprese, S RattiAbstract:The aim of this study was to assess the effect of total tocopherols and Tocotrienols of refined vegetable oils on oil radical-scavenging activity and to investigate the stability of the various homologues during the deep-fat frying of French fries. Eight different refined vegetable oils were investigated, having variable levels of natural tocopherols and Tocotrienols. A direct correlation between the radical-scavenging capacity of the oils, measured by the DPPH test, and the total content of natural tocopherols and Tocotrienols was found. Frying experiments showed that the stability of the different tocopherols and Tocotrienols present in the refined vegetable oils basically depend on two factors: the fatty acid composition of the oil, in particular polyunsaturated fatty acid content, and the kind of tocopherol and Tocotrienol homologues present. The more oxidizable the oil, on the basis of fatty acid composition, the more stable were the tocopherolic antioxidants. Among the different homologues, γ-Tocotrienol in palm super olein proved to be the least stable during the deep-fat frying, thus preserving the other homologues.
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tocopherols and Tocotrienols as free radical scavengers in refined vegetable oils and their stability during deep fat frying
Food Chemistry, 2007Co-Authors: M Rossi, C Alamprese, S RattiAbstract:The aim of this study was to assess the effect of total tocopherols and Tocotrienols of refined vegetable oils on oil radical-scavenging activity and to investigate the stability of the various homologues during the deep-fat frying of French fries. Eight different refined vegetable oils were investigated, having variable levels of natural tocopherols and Tocotrienols. A direct correlation between the radical-scavenging capacity of the oils, measured by the DPPH test, and the total content of natural tocopherols and Tocotrienols was found. Frying experiments showed that the stability of the different tocopherols and Tocotrienols present in the refined vegetable oils basically depend on two factors: the fatty acid composition of the oil, in particular polyunsaturated fatty acid content, and the kind of tocopherol and Tocotrienol homologues present. The more oxidizable the oil, on the basis of fatty acid composition, the more stable were the tocopherolic antioxidants. Among the different homologues, γ-Tocotrienol in palm super olein proved to be the least stable during the deep-fat frying, thus preserving the other homologues.
M Rossi - One of the best experts on this subject based on the ideXlab platform.
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tocopherols and Tocotrienols as free radical scavengers in refined vegetable oils and their stability during deep fat frying
Food Chemistry, 2007Co-Authors: M Rossi, C Alamprese, S RattiAbstract:The aim of this study was to assess the effect of total tocopherols and Tocotrienols of refined vegetable oils on oil radical-scavenging activity and to investigate the stability of the various homologues during the deep-fat frying of French fries. Eight different refined vegetable oils were investigated, having variable levels of natural tocopherols and Tocotrienols. A direct correlation between the radical-scavenging capacity of the oils, measured by the DPPH test, and the total content of natural tocopherols and Tocotrienols was found. Frying experiments showed that the stability of the different tocopherols and Tocotrienols present in the refined vegetable oils basically depend on two factors: the fatty acid composition of the oil, in particular polyunsaturated fatty acid content, and the kind of tocopherol and Tocotrienol homologues present. The more oxidizable the oil, on the basis of fatty acid composition, the more stable were the tocopherolic antioxidants. Among the different homologues, γ-Tocotrienol in palm super olein proved to be the least stable during the deep-fat frying, thus preserving the other homologues.
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tocopherols and Tocotrienols as free radical scavengers in refined vegetable oils and their stability during deep fat frying
Food Chemistry, 2007Co-Authors: M Rossi, C Alamprese, S RattiAbstract:The aim of this study was to assess the effect of total tocopherols and Tocotrienols of refined vegetable oils on oil radical-scavenging activity and to investigate the stability of the various homologues during the deep-fat frying of French fries. Eight different refined vegetable oils were investigated, having variable levels of natural tocopherols and Tocotrienols. A direct correlation between the radical-scavenging capacity of the oils, measured by the DPPH test, and the total content of natural tocopherols and Tocotrienols was found. Frying experiments showed that the stability of the different tocopherols and Tocotrienols present in the refined vegetable oils basically depend on two factors: the fatty acid composition of the oil, in particular polyunsaturated fatty acid content, and the kind of tocopherol and Tocotrienol homologues present. The more oxidizable the oil, on the basis of fatty acid composition, the more stable were the tocopherolic antioxidants. Among the different homologues, γ-Tocotrienol in palm super olein proved to be the least stable during the deep-fat frying, thus preserving the other homologues.
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 (α-, β-, γ-, and δ-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 (∼75 mg/kg of dry weight). β-Tocotrienol is the main vitamer found in hulled and dehulled wheats (from 33 to 43 mg/kg of dry weight), γ-tocopherol predominates in maize (45 mg/kg of dry weight) ), and α-Tocotrienol predominates in oat and barley (56 and 40 mg/kg of dry weight, re...
Kalanithi Nesaretnam - One of the best experts on this subject based on the ideXlab platform.
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A new formulation of Gamma Delta Tocotrienol has superior bioavailability compared to existing Tocotrienol-Rich Fraction in healthy human subjects
Scientific Reports, 2015Co-Authors: Puvaneswari Meganathan, Rafid Salim Jabir, Ho Gwo Fuang, Nirmala Bhoo-pathy, Roma Basu Choudhury, Nur Aishah Taib, Kalanithi Nesaretnam, Zamri ChikAbstract:Gamma and delta Tocotrienols are isomers of Vitamin E with established potency in pre-clinical anti-cancer research. This single-dose, randomized, crossover study aimed to compare the safety and bioavailability of a new formulation of Gamma Delta Tocotrienol (GDT) in comparison with the existing Tocotrienol-rich Fraction (TRF) in terms of gamma and delta isomers in healthy volunteers. Subjects were given either two 300 mg GDT (450 mg γ-T3 and 150 mg δ-T3) capsules or four 200 mg TRF (451.2 mg γ-T3 & 102.72 mg δ-T3) capsules and blood samples were taken at several time points over 24 hours. Plasma Tocotrienol concentrations were determined using HPLC method. The 90% CI for gamma and delta Tocotrienols for the ratio of log-transformation of GDT/TRF for C_max and AUC_0–∞ (values were anti-logged and expressed as a percentage) were beyond the bioequivalence limits (106.21–195.46, 154.11–195.93 and 52.35–99.66, 74.82–89.44 respectively). The Wilcoxon Signed Rank Test for T_max did not show any significant difference between GDT and TRF for both isomers (p > 0.05). No adverse events were reported during the entire period of study. GDT was found not bioequivalent to TRF, in terms of AUC and C_max. Gamma Tocotrienol in GDT showed superior bioavailability whilst delta Tocotrienol showed less bioavailability compared to TRF.
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Tocotrienols and breast cancer: the evidence to date
Genes & Nutrition, 2012Co-Authors: Kalanithi Nesaretnam, Puvaneswari Meganathan, Sheela Devi Veerasenan, Kanga Rani SelvadurayAbstract:Breast cancer is the second most frequent cancer affecting women worldwide after lung cancer. The toxicity factor associated with synthetic drugs has turned the attention toward natural compounds as the primary focus of interest as anticancer agents. Vitamin E derivatives consisting of the well-established tocopherols and their analogs namely Tocotrienols have been extensively studied due to their remarkable biological properties. While tocopherols have failed to offer protection, Tocotrienols, in particular, α-, δ-, and γ-Tocotrienols alone and in combination have demonstrated anticancer properties. The discovery of the antiangiogenic, antiproliferative, and apoptotic effects of Tocotrienols, as well as their role as an inducer of immunological functions, not only reveals a new horizon as a potent antitumor agent but also reinforces the notion that Tocotrienols are indeed more than antioxidants. On the basis of a transcriptomic platform, we have recently demonstrated a novel mechanism for Tocotrienol activity that involves estrogen receptor (ER) signaling. In silico simulations and in vitro binding analyses indicate a high affinity of specific forms of Tocotrienols for ERβ, but not for ERα. Moreover, we have demonstrated that specific Tocotrienols increase ERβ translocation into the nucleus which, in turn, activates the expression of estrogen-responsive genes ( MIC - 1, EGR - 1 and Cathepsin D ) in breast cancer cells only expressing ERβ cells (MDA-MB-231) and in cells expressing both ER isoforms (MCF-7). The binding of specific Tocotrienol forms to ERβ is associated with the alteration of cell morphology, caspase-3 activation, DNA fragmentation, and apoptosis. Furthermore, a recently concluded clinical trial seems to suggest that Tocotrienols in combination with tamoxifen may have the potential to extend breast cancer-specific survival.
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Vitamin E Tocotrienols: life beyond tocopherols.
Genes & nutrition, 2011Co-Authors: Bharat B. Aggarwal, Kalanithi NesaretnamAbstract:An extensive amount of work has been carried out on vitamin E, which was first identified as a “fertility factor” in 1938 by two researchers from the University of California, Berkeley. This vitamin E, referred to as tocopherol, consists of a chromanol ring with a 15-carbon isoprenoid chain. Based on the number and position of methyl groups on the chromanol ring, there are four saturated analogues. Almost 16,000 pubmed citations indicate that a lot is known about this vitamin. However, there is another vitamin E, called Tocotrienol, that has three trans double bonds in the isoprenoid tail and was first described in Nature in 1965. There is very little known about this vitamin E, as indicated by less than 1,000 (about 700) pubmed citations. Therefore, the first International Conference on Tocotrienols and its Role in Chronic Diseases was organized in Las Vegas, USA, from July 29–30th 2010 to discuss the chemistry, biology, and clinical implication of Tocotrienols and was sponsored by the Malaysian Palm Oil Board. This was also timely as Tocotrienol received GRAS status from USFDA in April 2010. It was a two-day conference, with 27 speakers. From this conference, it became clear that Tocotrienols exhibit health benefits quite different from that of tocopherols, and in most cases, these activities are superior for human use. There were also indications that different isomers of Tocotrienols exhibit distinct activities. For instance, while α-Tocotrienol was highly effective in the brain for cerebral ischemia, γ- and δ-Tocotrienol exhibited strong anticancer activities. The current special issue of Genes and Nutrition is devoted to various aspects of Tocotrienols as discussed at this conference. We sought to build upon the various unique and novel benefits of Tocotrienols, for example, the role of Tocotrienols in cardioprotection based on structure–function relationships, the radioprotective properties of γ-Tocotrienol as well as the protective effects of vitamin E against hypercholesterolemia-induced age-related disease (Das; Kartal Ozer). The molecular mechanism of Tocotrienols was equally appreciated and addressed using comparative gene expression profiling in tocol-treated endothelial cells (Hauer Jensen). While information continues to emerge on the anticancer effects of Tocotrienols, a review on Tocotrienols and breast cancer aims to update on the present understanding of Tocotrienols in clinical trials (Nesaretnam), likewise for the anti-cancer mechanism of Tocotrienols where multiple cell signaling pathways were addressed and compared against the pathways involved in tocopherol (Aggarwal; Galli). The concept of combination approach with γ-Tocotrienol and statin or receptor tyrosine kinase inhibitor was also reviewed (Sylvester). In addition to that, the role of Tocotrienols in attenuating tumor angiogenesis was re-examined using pro-angiogenic markers in human umbilical vein endothelial cells and murine mammary cancer cells (Selvaduray). Although not every presentation made at the conference is represented in this issue, it gives the readers an idea about the diversity of applications for Tocotrienols. Finally, our sincere thanks are extended to all participants and working committee in making this event a success. The meeting stimulated fruitful discussions on Tocotrienols among international researchers, and we look forward to meeting again in July 2011 at the second conference.
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Tocotrienols Suppress Proinflammatory Markers and Cyclooxygenase-2 Expression in RAW264.7 Macrophages
Lipids, 2009Co-Authors: Mun-li Yam, Sitti Rahma Abdul Hafid, Hwee-ming Cheng, Kalanithi NesaretnamAbstract:Tocotrienols are powerful chain breaking antioxidant. Moreover, they are now known to exhibit various non-antioxidant properties such as anti-cancer, neuroprotective and hypocholesterolemic functions. This study was undertaken to investigate the anti-inflammatory effects of Tocotrienol-rich fraction (TRF) and individual Tocotrienol isoforms namely δ-, γ-, and α-Tocotrienol on lipopolysaccharide-stimulated RAW264.7 macrophages. The widely studied vitamin E form, α-tocopherol, was used as comparison. Stimulation of RAW264.7 with lipopolysaccharide induced the release of various inflammatory markers. 10 μg/ml of TRF and all Tocotrienol isoforms significantly inhibited the production of interleukin-6 and nitric oxide. However, only α-Tocotrienol demonstrated a significant effect in lowering tumor necrosis factor-α production. Besides, TRF and all Tocotrienol isoforms except γ-Tocotrienol reduced prostaglandin E_2 release. It was accompanied by the down-regulation of cyclooxygenase-2 gene expression by all vitamin E forms except α-tocopherol. Collectively, the data suggested that Tocotrienols are better anti-inflammatory agents than α-tocopherol and the most effective form is δ-Tocotrienol.
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Tocotrienols and cancer: beyond antioxidant activity.
European Journal of Lipid Science and Technology, 2007Co-Authors: Kalanithi Nesaretnam, Wong Weng Yew, Mohd Basri WahidAbstract:The edible oil industry has emerged as an important provider of raw material for the extraction of vitamin E. Vegetable oils, especially the seed oils, are rich sources of tocopherols. However, in palm oil, vitamin E occurs as a complex mixture of tocopherols and Tocotrienols. Various Tocotrienol isomers of vitamin E in palm oil have been reported to possess interesting biological and physiological properties not generally evident with tocopherol-rich vitamin E preparations. They include potential blood cholesterol-lowering and cardioprotective effects, more efficient antioxidant activity in biological systems, and possible anti-cancer and neuroprotective effects. With the emergence of palm oil as the largest edible oil in world markets, technology is now available to extract Tocotrienol-rich palm vitamin E. Initiatives in Malaysia to manufacture biodiesel will further generate large amounts of micronutrients, especially Tocotrienols, to be available to the nutraceutical and functional food industry.
Mokenge P. Malafa - One of the best experts on this subject based on the ideXlab platform.
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vitamin e δ Tocotrienol augments the antitumor activity of gemcitabine and suppresses constitutive nf κb activation in pancreatic cancer
Molecular Cancer Therapeutics, 2011Co-Authors: Kazim Husain, Said M. Sebti, Rony A Francois, Teruo Yamauchi, Marta Perez, Mokenge P. MalafaAbstract:The nuclear factor-κB (NF-κB) transcription factor functions as a crucial regulator of cell survival and chemoresistance in pancreatic cancer. Recent studies suggest that Tocotrienols, which are the unsaturated forms of vitamin E, are a promising class of anti-cancer compounds that inhibit the growth and survival of many cancer cells, including pancreatic cancer. Here, we show that Tocotrienols inhibited NF-κB activity and the survival of human pancreatic cancer cells in vitro and in vivo. Importantly, we found the bioactivity of the 4 natural Tocotrienol compounds (α-, β-, δ-, and γ-Tocotrienol) to be directly related to their ability to suppress NF-κB activity in vitro and in vivo. The most bioactive Tocotrienol for pancreatic cancer, δ-Tocotrienol, significantly enhanced the efficacy of gemcitabine to inhibit pancreatic cancer growth and survival in vitro and in vivo. Moreover, we found that δ-Tocotrienol augmentation of gemcitabine activity in pancreatic cancer cells and tumors is associated with significant suppression of NF-κB activity and the expression of NF-κB transcriptional targets [Bcl-XL, X-linked inhibitor of apoptosis (XIAP), and survivin]. Our study represents the first comprehensive pre-clinical evaluation of the activity of natural vitamin E compounds in pancreatic cancer. Given these results, we are conducting a phase I trial of δ-Tocotrienol in patients with pancreatic cancer utilizing pancreatic tumor cell survival and NF-κB signaling components as intermediate biomarkers. Our data also support future clinical investigation of δ-Tocotrienol to augment gemcitabine activity in pancreatic cancer.
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Delta-Tocotrienol is the most bioactive natural Tocotrienol in the prevention of pancreatic cancer transformation
Cancer Research, 2008Co-Authors: Kazim Husain, Said M. Sebti, Rony A Francois, Teruo Yamauchi, Mokenge P. MalafaAbstract:3826 Background: Pancreatic cancer is one of the most lethal cancers in need of novel interventions. A role for dietary bioactive compounds in pancreatic cancer prevention is plausible because epidemiological studies indicate that consumption of fruits, vegetables, and cereal foods is associated with a lower risk of developing pancreatic cancer. Tocotrienols are bioactive components of cereal foods such as oats, barley, rice bran, and palm. These compounds have been demonstrated to have anticancer and chemopreventive activity in a wide variety of cancer types; however their activity in pancreatic cancer is unknown. In this study we investigated the comparative effects of the four natural Tocotrienol compounds in order to determine the most bioactive Tocotrienol against pancreatic cancer Methods: We first determined the anti-proliferative (MTT assay) and pro-apoptotic activity of α, β, γ and δ-Tocotrienol in immortalized normal human pancreatic ductal epithelial cells (HPDE C7), HPDE cells transformed with oncogenic Kras (C7-Kras), as well as human pancreatic cancer cell lines MiaPaCa-2 and AsPc-1. We then determined the effect of the Tocotrienol compounds on malignant transformation (colony formation) in MiaPaca-2 cells and NF-κB/p65 activity in these cells. The activity of the Tocotrienol was also compared to gemcitabine, α-tocopherol, and δ-tocopherol. Results: Tocotrienols significantly inhibited the cell growth of transformed C7-Kras, and pancreatic cancer cells in a concentration and time-dependent manner but had no effect on ‘normal’ HPDE cells. The IC 50 of growth inhibition were 40, 45 and 60 μ M for δ, γ and β Tocotrienol compounds, respectively. The IC 50 of growth inhibition for gemcitabine was 20 μ M. In contrast α-Tocotrienol, α-tocopherol and δ-tocopherol had no growth inhibitory activity. Malignant transformation was inhibited by 70, 30, 19 and 6% with δ, γ, β and α Tocotrienol compounds, respectively in MiaPaca-2 cells. Malignant transformation inhibition for gemcitabine was 89%.The apoptosis inducing activity of δ Tocotrienol was far greater than γ and β-Tocotrienols and gemcitabine. Furthermore nuclear DNA binding of NF-κB/p65 activity was inhibited by 36, 30, 15 and 5% with δ, γ, β and α Tocotrienols, respectively. Conclusion: (1) δ-Tocotrienol is the most bioactive Tocotrienol compound against pancreatic cancer; (2) δ-Tocotrienol is not toxic to non-transformed pancreatic epithelial cells; (3) δ-Tocotrienol has more apoptotic activity against pancreatic cancer cells compared to gemcitabine; (4) δ and γ-Tocotrienols significantly inhibit nuclear DNA binding activity of NF-κB/p65. These data support further studies to determine the role of δ-Tocotrienol in the prevention of pancreatic cancer progression.
