Search

Now under Clusiaceae and Hypericaceae, Clusia and Hypericum were previously categorized under one family until they were divided in 2003 by the APG III system. The Clusia genus is characterized by the presence of tocotrienol derivatives with antiangiogenic properties, and only Hypericum perforatum tocochromanol content has been studied in the Hypericum genus. Twelve species were analyzed: H. aegypticum , H. calycinum , H. empetrifolium , H. lancasteri , H. olympicum f. minus 'Sulphureum', H. perforatum , H. xylosteifolium , C. fluminensis , C. minor , C. odorata , C. palmicida , and C. tocuchensis . Plant leaves were analyzed for their tocochromanol (α-, β-, γ-, and δ-tocotrienol and tocopherol) contents using a reverse-phase high-performance liquid chromatography with fluorescent light detector (RP-HPLC-FLD) method. While α-tocopherol (α-T) was present in the highest proportion, the leaves had significant tocotrienol (T3) contents. Following α-T, δ-T3 was present in most Clusia samples, and γ-T3 in most Hypericum samples, except H. olympicum , in which α-T3 followed. C. minor had the highest α-T (112.72 mg 100 g -1 ) and total tocochromanol (141.43 mg 100 g -1 ) content, followed by C. palmicida (65.97 and 82.96 mg 100 g -1 , respectively) and H. olympicum (α-T 32.08, α-T3 30.68, and total tocochromanols 89.06 mg 100 g -1 ). The Hypericum genus is a valuable source of tocotrienols, with potential use after purification.

The high content of vitamin E, including tocopherols and tocotrienols (TCF-TTE), in palm oil ( Elaeis guineensis ) has made it a promising candidate for the alternative treatment of atopic dermatitis (AD). However, the limited solubility of TCF-TTE has restricted its therapeutic efficacy. In this study, pluronic-based micelles (MCs) encapsulating palm oil-derived TCF-TTE were formulated with dissolvable microarray patch-micelles (DMP-MC) using carboxymethyl cellulose (CMC) synthesized from empty fruit bunches of palm to optimize its delivery for AD. The MC was prepared using a direct dissolution method using Pluronic F68 and F127. The results showed that MC increased the solubility of TCF-TTE, which was further confirmed by an in vitro study where 90.23 ± 2.07% TCF and 4.56 ± 1.36% TTE were released compared to the unencapsulated TCF-TTE extract. Furthermore, CMC biopolymers and MC integrated into DMP-MC with polyvinylpyrrolidone (PVP) exhibited favorable physical properties, such as mechanical strength and penetration ability. DMP-MC also exhibited a better platform with lower permeation, indicating higher retention and increased localized effects on AD skin than cream-MC. Additionally, dermatokinetic profile parameters showed significant improvement. The mean residence time (MRT) parameter indicated that TCF-TTE was retained for longer times 19.28 ± 0.02 h and 20.68 ± 0.01 h. Moreover, an in vivo study revealed that DMP-MC could relieve AD symptoms more rapidly than oral doses and cream-MC, indicating that DMP-MC proved to be more efficient. Furthermore, DMP-MC showed no tissue destruction (granulation and fibrosis) in rats treated with DMP-MC on the seventh day. Therefore, this study successfully developed the MC formula in DMP-MC formulation using synthesized CMC, which could potentially improve AD's therapeutic efficacy.

Grape processing generates large amounts of by-products, including seeds rich in hydrophilic and lipophilic antioxidants. This study demonstrates, for the first time, that subjecting grape seeds to a single ultrasound-assisted extraction (UAE) with aqueous ethanolic solutions yields both flavan-3-ols and tocochromanols in the final extract. Notably, the water content in ethanol significantly influences the extractability of tocochromanols more than flavan-3-ols. Solid-to-solvent ratios of 1:50 to 1:2 were tested for both analytical and industrial applications. A sustainable analytical approach for recovering flavan-3-ols and tocochromanols using 60% and 96.4% ethanol extractions was validated and employed to profile nineteen genotypes of lesser-studied interspecific grape crosses (Vitis spp.). Different genotypes showed a wide range of concentrations of tocopherols (1.6-6.3 mg/100 g), tocotrienols (1.0-17.4 mg/100 g), and flavan-3-ols (861-9994 mg/100 g). This indicated that the genetic background and maturity of the plant material are crucial factors from an industrial perspective due to the initial concentration of bioactive compounds. Finally, the study also discussed the fundamental aspects of hydrophobic antioxidant extractability from the lipid matrix with aqueous ethanol solutions and the limitations of the workflow, such as the non-extractable tocochromanols and their esters and the losses of these lipophilic antioxidants during extraction., Competing Interests: Declaration of competing Interest All other authors declare no conflict of interest., (Copyright © 2024. Published by Elsevier Ltd.)

Calendula officinalis L. has numerous health-promoting properties due to the presence of a large number of lipophilic compounds. Their effective delivery to the body requires the use of an appropriate technique such as emulsification. So, the main purpose of this study was to understand how the profile of lipophilic compounds from pot marigold and the pro-health potential are shaped by different types of protein, oil, and drying techniques in o/w nanoemulsion. To obtain this, the profiles of carotenoid compounds and tocols were measured. Additionally, antioxidant potential and the ability to inhibit α-amylase and α-glucosidase were measured. Pea protein emulsion exhibited a higher final content of carotenoid compounds (23.72-39.74 mg/100 g), whereas those with whey protein had stronger α-amylase inhibition (487.70 mg/mL). The predominant compounds in the studied nanoemulsions were β-carotene (between 19% and 40%), followed by α-tocopherol/γ-tocopherol. The type of proteins shaped the health-promoting properties and determined the content of health-promoting compounds.

It has generally been accepted that vitamin E refers to a group of tocochromanols, α-, β-, γ-, and δ-tocopherols and the corresponding four tocotrienols. Recently, Azzi and colleagues proposed to restrict the term vitamin E only to RRR-α-tocopherol, not to other tocopherols and tocotrienols (Azzi A et al. Free Radic Biol Med. 2023; 207:178-180. doi: 10.1016/j.freeradbiomed.2023.06.029). The aim of this paper is to express our opinion on the nomenclature of vitamin E based on available scientific data. In our opinion, it would be inappropriate to exclude all the tocochromanols other than RRR-α-tocopherol from the vitamin E group at this stage when the molecular mechanisms showing how vitamin E deficiency causes diseases such as ataxia and how vitamin E prevents/reverses such diseases are not elucidated. Understanding of whole functions of tocochromanols including underlying mechanisms and dynamics is essential before revision of currently accepted definition of vitamin E. The potential roles of γ-tocopherol and tocotrienols are discussed despite whether they are vitamin function should be clarified in the future studies., Competing Interests: Declaration of competing interest There is no declaration of competing interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Glucocorticoid-induced osteogenic dysfunction is the main pathologyical mechanism underlying the development of glucocorticoid-induced osteoporosis. Glucocorticoids promote adipogenic differentiation and osteoblast apoptosis through various pathways. Various ongoing studies are exploring the potential of natural products in preventing glucocorticoid-induced osteoporosis. Preclinical studies have consistently shown the bone protective effects of tocotrienol through its antioxidant and anabolic effects. This review aims to summarise the potential mechanisms of tocotrienol in preventing glucocorticoid-induced osteoporosis based on existing in vivo and in vitro evidence. The current literature showed that tocotrienol prevents oxidative damage on osteoblasts exposed to high levels of glucocorticoids. Tocotrienol reduces lipid peroxidation and increases oxidative stress enzyme activities. The reduction in oxidative stress protects the osteoblasts and preserves the bone microstructure and biomechanical strength of glucocorticoid-treated animals. In other animal models, tocotrienol has been shown to activate the Wnt/β-catenin pathway and lower the RANKL/OPG ratio, which are the targets of glucocorticoids. In conclusion, tocotrienol enhances osteogenic differentiation and bone formation in glucocorticoid-treated osteoblasts while improving structural integrity in glucocorticoid-treated rats. This is achieved by preventing oxidative stress and osteoblast apoptosis. However, these preclinical results should be validated in a randomised controlled trial.

Vitamin E is a group of isoprenoid chromanols with different biological activities. It comprises eight oil-soluble compounds: four tocopherols, namely, α-, β-, γ-, and δ-tocopherols; and four tocotrienols, namely, α-, β-, γ, and δ-tocotrienols. Vitamin E isomers are well-known for their antioxidant activity, gene-regulation effects, and anti-inflammatory and nephroprotective properties. Considering that vitamin E is exclusively synthesized by photosynthetic organisms, animals can only acquire it through their diet. Plant-based food is the primary source of vitamin E; hence, oils, nuts, fruits, and vegetables with high contents of vitamin E are mostly consumed after processing, including industrial processes and home-cooking, which involve vitamin E profile and content alteration during their preparation. Accordingly, it is essential to identify the vitamin E content and profile in foodstuff to match daily intake requirements. This review summarizes recent advances in vitamin E chemistry, metabolism and metabolites, current knowledge on their contents and profiles in raw and processed plant foods, and finally, their modern developments in analytical methods., (© 2022 Institute of Food Technologists®.)

Background: Juices are currently a fast-growing segment in the fruit and vegetable industry sector. However, there are still no reports on the diversity of the phytochemical profile and health-promoting properties of commercial sea buckthorn (Hippophaë rhamnoides) juices. This study aimed to identify and quantify phytoprostanes, phytofurans by ultra high-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-QqQ-MS/MS), tocopherols, tocotrienols by ultra-performance liquid chromatography coupled with a fluorescence detector (UPLC-FL), carotenoids, and free amino acids by ultra-performance liquid chromatography coupled with a photodiode detector-quadrupole and tandem time-of-flight mass spectrometry (UPLC-PDA-Q/TOF-MS), and assess their anti-cholinergic, anti-diabetic, anti-obesity, anti-inflammatory, and antioxidant potential by in vitro assays of commercial sea buckthorn juices., Results: Phytoprostanes (PhytoPs) and phytofurans (PhytoFs) in sea buckthorn juices were identified for the first time. Juices contained eight F 1 -, D 1 -, B 1 - and L 1 -phytoprostanes and one phytofuran (32.31-1523.51 ng and up to 101.47 μg/100 g dry weight (DW)), four tocopherol congeners (22.23-94.08 mg 100 g -1 DW) and three tocotrienols (5.93-25.34 mg 100 g -1 DW). Eighteen carotenoids were identified, including ten xanthophylls, seven carotenes and phytofluene, at a concentration of 133.65 to 839.89 mg 100 g -1 DW. Among the 20 amino acids (175.92-1822.60 mg 100 g -1 DW), asparagine was dominant, and essential and conditionally essential amino acids constituted 11 to 41% of the total. The anti-enzyme and antioxidant potential of juices correlated selectively with the composition., Conclusion: Sea buckthorn juice can be a valuable dietary source of vitamins E and A, oxylipins and amino acids, used in the prevention of metabolic syndrome, inflammation, and neurodegenerative processes. The differentiation of the composition and the bioactive potential of commercial juices indicate that, for the consumer, it should be important to choose juices from the declared berry cultivars and crops. © 2021 Society of Chemical Industry., (© 2021 Society of Chemical Industry.)

Background: Throughout the past decade, Pickering emulsion has been increasingly utilized for the encapsulation of bioactive compounds due to its high stability and biocompatibility. In the present work, palm tocotrienols were initially encapsulated in a calcium carbonate Pickering emulsion, which was then subjected to alginate gelation and subsequent chitosan coating. The effects of wall material (alginate and chitosan) concentrations, gelation pH and time, and chitosan coating time on the encapsulation efficiency of palm tocotrienols were explored., Results: Our findings revealed that uncoated alginate microcapsules ruptured upon drying and exhibited low encapsulation efficiency (13.81 ± 2.76%). However, the addition of chitosan successfully provided a more complex and rigid external wall structure to enhance the stability of the microcapsules. By prolonging the crosslinking time from 5 to 30 min and increasing the chitosan concentration from 0.1% to 0.5%, the oil encapsulation efficiency was increased by 28%. Under the right gelation pH (pH 4), the extension of gelation time from 1 to 12 h resulted in an increase in alginate-Ca 2+ crosslinkings, thus strengthening the microcapsules., Conclusion: With the optimum formulation and process parameters, a high encapsulation efficiency (81.49 ± 1.75%) with an elevated oil loading efficiency (63.58 ± 2.96%) were achieved. The final product is biocompatible and can potentially be used for the delivery of palm tocotrienols. © 2021 Society of Chemical Industry., (© 2021 Society of Chemical Industry.)

Menopause is the leading cause of osteoporosis for elderly women due to imbalanced bone remodelling in the absence of oestrogen. The ability of tocotrienol in reversing established bone loss due to oestrogen deficiency remains unclear despite the plenitude of evidence showcasing its preventive effects. This study aimed to investigate the effects of self-emulsified annatto tocotrienol (SEAT) on bone histomorphometry and remodelling in ovariectomised rats. Female Sprague Dawley rats (n=36) were randomly assigned into baseline, sham, ovariectomised (OVX) control, OVX-treated with annatto tocotrienol (AT) (60 mg/kg), SEAT (60 mg/kg) and raloxifene (1 mg/kg). Daily treatment given through oral gavage was started two months after castration. The rats were euthanised after eight weeks of treatment. Blood was collected for bone biomarkers. Femur and lumbar bones were collected for histomorphometry and remodelling markers. The results showed that AT and SEAT improved osteoblast numbers and trabecular mineralisation rate (p<0.05 vs untreated OVX). AT also decreased skeletal sclerostin expression in OVX rats (p<0.05 vs untreated OVX). Similar effects were observed in the raloxifene-treated group. Only SEAT significantly increased bone formation rate and reduced RANKL/OPG ratio (p<0.05 vs untreated OVX). However, no changes in osteoclast-related parameters were observed among the groups (p>0.05). In conclusion, SEAT exerts potential skeletal anabolic properties by increasing bone formation, suppressing sclerostin expression and reducing RANKL/OPG ratio in rats with oestrogen deficiency., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Tocopherols and tocotrienols are natural compounds of plant origin, available in the nature. They are supplied in various amounts in a diet, mainly from vegetable oils, some oilseeds, and nuts. The main forms in the diet are α- and γ-tocopherol, due to the highest content in food products. Nevertheless, α-tocopherol is the main form of vitamin E with the highest tissue concentration. The α- forms of both tocopherols and tocotrienols are considered as the most metabolically active. Currently, research results indicate also a greater antioxidant potential of tocotrienols than tocopherols. Moreover, the biological role of vitamin E metabolites have received increasing interest. The aim of this review is to update the knowledge of tocopherol and tocotrienol bioactivity, with a particular focus on their bioavailability, distribution, and metabolism determinants in humans. Almost one hundred years after the start of research on α-tocopherol, its biological properties are still under investigation. For several decades, researchers' interest in the biological importance of other forms of vitamin E has also been growing. Some of the functions, for instance the antioxidant functions of α- and γ-tocopherols, have been confirmed in humans, while others, such as the relationship with metabolic disorders, are still under investigation. Some studies, which analyzed the biological role and mechanisms of tocopherols and tocotrienols over the past few years described new and even unexpected cellular and molecular properties that will be the subject of future research.

Tocotrienol has been shown to prevent bone loss in animal models of postmenopausal osteoporosis, but the low oral bioavailability might limit its use. A self-emulsifying drug delivery system (SEDDS) could increase the bioavailability of tocotrienol. However, evidence of this system in improving the skeletal effects of tocotrienol is scanty. This study aims to evaluate the therapeutic efficacy of annatto tocotrienol with SEDDS in a rat model of postmenopausal bone loss. Ten-month-old female Sprague Dawley rats were randomized into six groups. The baseline group was euthanatized at the onset of the study. Four other groups underwent ovariectomy to induce estrogen deficiency. The sham underwent similar surgery procedure, but their ovaries were retained. Eight weeks after surgery, the ovariectomized rats received one of the four different regimens orally daily: (a) SEDDS, (b) annatto tocotrienol [60 mg/kg body weight (b.w.)] without SEDDS, (c) annatto-tocotrienol (60 mg/kg b.w.) with SEDDS, (d) raloxifene (1 mg/kg b.w.). After eight weeks of treatment, blood was collected for the measurement of delta-tocotrienol level and oxidative stress markers. The rats were euthanized and their bones were harvested for the evaluation of the bone microstructure, calcium content and strength. Circulating delta-tocotrienol level was significantly higher in rats receiving annatto tocotrienol with SEDDS compared to the group receiving unformulated annatto-tocotrienol (p < 0.05). Treatment with unformulated or SEDDS-formulated annatto tocotrienol improved cortical bone thickness, preserved bone calcium content, increased bone biomechanical strength and increased antioxidant enzyme activities compared with the ovariectomized group (p < 0.05). Only SEDDS-formulated annatto tocotrienol improved trabecular microstructure, bone stiffness and lowered malondialdehyde level (p < 0.05 vs the ovariectomized group). The improvement caused by annatto tocotrienol was comparable to raloxifene. In conclusion, SEDDS improves the bioavailability and skeletal therapeutic effects of annatto tocotrienol in a rat model of postmenopausal bone loss. This formulation should be tested in a human clinical trial to validate its efficacy., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Recent research has identified minor homologs of vitamin E with one or two double bonds in the side-chain, namely tocomonoenol (T1) and tocodienol (T2), in natural products. We first explored the effectiveness of partial hydrogenation for generating minor tocochromanols from tocotrienol (T3). During hydrogenation with pure α-T3 as a substrate, the side-chain was partially saturated in a time-dependent manner, and a large amount of α-T1 and α-T2 was obtained. To investigate the beneficial effects of the hydrogenated product, we fed diabetic obese KK-A y mice with a hydrogenated T3 mixture (HT3). Feeding HT3 revealed tissue-specific accumulation of tocochromanols, ameliorated hyperglycemia and improved ratio of high-density lipoprotein cholesterol to total cholesterol in serum, with invariant body weight and fat mass. Hence, we propose that hydrogenation is a useful method for generating T1 and T2 homologs, which can be applied to explore the structure-related function of tocochromanols.

Vitamin E, a natural antioxidant, is of interest to scientists, health care pundits and faddists; its nutritional and biomedical attributes may be validated, anecdotal or fantasy. Vitamin E is a mixture of tocopherols (TPs) and tocotrienols (T-3s), each class having four substitutional isomers (α-, β-, γ-, δ-). Vitamin E analogues attain only low concentrations in most tissues, necessitating exacting invasive techniques for analytical research. Quantitative positron emission tomography (PET) with an F-18-labeled molecular probe would expedite access to Vitamin E's biodistributions and pharmacokinetics via non-invasive temporal imaging. ( R )-6-(3-[ 18 F]Fluoropropoxy)-2,7,8-trimethyl-2-(4,8,12-trimethyltrideca-3,7,11-trien-1-yl)-chromane ([ 18 F]F-γ-T-3) was prepared for this purpose. [ 18 F]F-γ-T-3 was synthesized from γ-T-3 in two steps: (i) 1,3-di- O -tosylpropane was introduced at C6-O to form TsO-γ-T-3, and (ii) reaction of this tosylate with [ 18 F]fluoride in DMF/K 222 . Non-radioactive F-γ-T-3 was synthesized by reaction of γ-T-3 with 3-fluoropropyl methanesulfonate. [ 18 F]F-γ-T-3 biodistribution in a murine tumor model was imaged using a small-animal PET scanner. F-γ-T-3 was prepared in 61% chemical yield. [ 18 F]F-γ-T-3 was synthesized in acceptable radiochemical yield (RCY 12%) with high radiochemical purity (>99% RCP) in 45 min. Preliminary F-18 PET images in mice showed upper abdominal accumulation with evidence of renal clearance, only low concentrations in the thorax (lung/heart) and head, and rapid clearance from blood. [ 18 F]F-γ-T-3 shows promise as an F-18 PET tracer for detailed in vivo studies of Vitamin E. The labeling procedure provides acceptable RCY, high RCP and pertinence to all eight Vitamin E analogues.

Tocotrienols (T3) are vitamin E components that inhibit 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGR), a primary target for cholesterol management. T3 was extracted from rice bran (RBE) using ultrasonic energy keeping solute: solvent ratio, power and time on specific energy and T3 concentration as responses as per Box-Behnken Design. The lowest specific energy (52.38 ± 0.14 J mL -1 ) uptake by the sample was most effective in enhancing the concentration of T3 in RBE (199.34 ± 0.63 μg mL -1 ). In vitro HMGR kinetics and in silico binding interactions of the identified α-, δ- and γ-T3 fractions were studied. Enzyme kinetic studies revealed an uncompetitive mode of inhibition by α-T3, γ-T3, and RBE and a mixed mode of inhibition for δ-T3. γ-T3 showed lowest IC 50 concentration (11.33 μg mL -1 ) followed by α-T3 (16.73 μg mL -1 ), RBE (20.45 μg mL -1 ) and δ-T3 (23.16 μg mL -1 ). Molecular docking studies highlighted the hydrogen bonding of δ-T3 with Gln766 and α- and γ-T3 with Met655 and Val805 amino acid residues at the NADPH binding site of HMGR. Results indicate the potential use of T3 enriched RBE optimally extracted using ultrasound as potent HMGR inhibitor., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

: Oxidative stress plays an important role in retinal neurodegeneration and angiogenesis associated with diabetes. In this study, we investigated the effect of the tocotrienol-rich fraction (TRF), a potent antioxidant, against diabetes-induced changes in retinal layer thickness (RLT), retinal cell count (RCC), retinal cell apoptosis, and retinal expression of vascular endothelial growth factor (VEGF) in rats. Additionally, the efficacy of TRF after administration by two different routes was compared. The diabetes was induced in Sprague-Dawley rats by intraperitoneal injection of streptozotocin. Subsequently, diabetic rats received either oral or topical treatment with vehicle or TRF. Additionally, a group of non-diabetic rats was included with either oral or topical treatment with a vehicle. After 12 weeks of the treatment period, rats were euthanized, and retinas were collected for measurement of RLT, RCC, retinal cell apoptosis, and VEGF expression. RLT and RCC in the ganglion cell layer were reduced in all diabetic groups compared to control groups ( p < 0.01). However, at the end of the experimental period, oral TRF-treated rats showed a significantly greater RLT compared to topical TRF-treated rats. A similar observation was made for retinal cell apoptosis and VEGF expression. In conclusion, oral TRF supplementation protects against retinal degenerative changes and an increase in VEGF expression in rats with streptozotocin-induced diabetic retinopathy. Similar effects were not observed after topical administration of TRF., Competing Interests: The authors declare no conflict of interest.

Tumor-targeted nanoparticle delivery system has been known as a substitute and capable achievement in cancer treatment compared to conventional methods. In this study, we examined potential application of ɑ-tocotrienol-Precirol formulation to enhance efficiency of doxorubicin (DOX) in induction of apoptosis in HUH-7 hepatocarcinoma cells. ɑ-tocotrienol-loaded nanoparticles were characterized at the point of zeta potential, particle size, scanning electron microscope (SEM), and cell internalization. To evaluate antiproliferative effects of formulation, apoptosis, cell cycle procedure, flow cytometry, and MTT assays were employed. Optimum size of the ɑ-tocotrienol formulation revealed narrow size distribution with mean average of 78 ± 3 nm. IC 50 values for ɑ-tocotrienol and ɑ-tocotrienol-nano structured lipid carriers after 24 h were 15 ± 0.6 and 10 ± 0.03 µM, respectively. After incubation of cells with ɑ-tocotrienol-loaded careers, the rate of cell proliferation decreased from 53 ± 6.1 to 34 ± 7.1% ( P  < 0.05). A significant improvement in the apoptosis percentage was revealed after treatment of the HUH-7 cell line with DOX and ɑ-tocotrienol careers ( P  < 0.05). Gene expression results demonstrated a marked decrease in survivin and increase in Bid and Bax levels. Our findings suggest that ɑ-tocotrienol-loaded nanoparticles elevate DOX efficacy in HUH-7 hepatocarcinoma cell.

Diabetes mellitus is a metabolic disorder characterized by the development of vascular complications associated with high morbidity and mortality and the consequent relevant costs for the public health systems. Diabetic kidney disease is one of these complications that represent the main cause of end-stage renal disease in Western countries. Hyperglycemia, inflammation, and oxidative stress contribute to its physiopathology, and several investigations have been performed to evaluate the role of antioxidant supplementation as a complementary approach for the prevention and control of diabetes and associated disturbances. Vitamin E compounds, including different types of tocopherols and tocotrienols, have been considered as a treatment to tackle major cardiovascular outcomes in diabetic subjects, but often with conflicting or even negative results. However, their effects on diabetic nephropathy are even less clear, despite several intervention studies that showed the improvement of renal parameters after supplementation in patients with diabetic kidney disease. Then we performed a review of the literature about the role of vitamin E supplementation on diabetic nephropathy, also describing the underlying antioxidant, anti-inflammatory, and metabolic mechanisms to evaluate the possible use of tocopherols and tocotrienols in clinical practice.

The aim of this article is to correct a very general error in scientific articles, in textbooks and in the Internet that has become an accepted fact. In this literature, the term "vitamin E″ is used for several similar molecules (both tocopherols and tocotrienols) that have never been shown to have vitamin property, i.e. a protective effect against the human deficiency disease. In fact, the name "vitamin E″ should only be used to define molecules that prevent the human deficiency disease "Ataxia with Vitamin E Deficiency" (AVED). Only one such molecule is known, α-tocopherol. This error may confuse consumers as well as medical doctors, who prescribe vitamin E without realizing that the current use of the name includes molecules of unknown, if not unwanted functions., (Copyright © 2019 The Author. Published by Elsevier B.V. All rights reserved.)

Background: The seeds of Vitis vinifera grapes have been studied extensively but knowledge about the interspecific crosses of other Vitis species (e.g. V. vinifera, V. amurensis, V. rupestris, V. riparia, and V. labruska) is very limited., Results: The oil yields recovered from the grape seeds ranged between 7 and 160 g kg -1 dw. The main fatty acids were linoleic (72.5-83.1%), oleic (6.2-15.5%), and palmitic (5.4-13.2%), which together constituted 92.8-97.1% of the total detected fatty acids. The total concentration of tocopherol (T) and tocotrienol (T3) homologues was between 0.785 and 9.033 g kg -1 oil. The concentration of sterols varied significantly and ranged between 2.912 and 105.962 g kg -1 oil. The β-sitosterol constituted 68.2-86.3% of the total content of sterols. The oil yield in grape seeds significantly correlated with the oleic acid, α-linolenic acid, α-T, α-T3, γ-T3, campesterol, Δ5-stigmasterol, β-sitosterol, and total Ts + T3 s and sterols., Conclusion: The present study demonstrated that seed oil recovered from different interspecific Vitis crosses is a rich source of minor lipophilic bioactive compounds, especially genotypes with low oil content. They can be used to enrich plant oils that are poor in tocotrienols and/or phytosterols without changing the fatty acid composition of main oil, due to low enrichment quantities (micro-blends). © 2018 Society of Chemical Industry., (© 2018 Society of Chemical Industry.)

Male osteoporosis is a significant but undetermined healthcare problem. Men suffer from a higher mortality rate post-fracture than women and they are marginalized in osteoporosis treatment. The current prophylactic agents for osteoporosis are limited. Functional food components such as tocotrienol may be an alternative option for osteoporosis prevention in men. This paper aims to review the current evidence regarding the skeletal effects of tocotrienol in animal models of male osteoporosis and its potential antiosteoporotic mechanism. The efficacy of tocotrienol of various sources (single isoform, palm and annatto vitamin E mixture) had been tested in animal models of bone loss induced by testosterone deficiency (orchidectomy and buserelin), metabolic syndrome, nicotine, alcoholism, and glucocorticoid. The treated animals showed improvements ranging from bone microstructural indices, histomorphometric indices, calcium content, and mechanical strength. The bone-sparing effects of tocotrienol may be exerted through its antioxidant, anti-inflammatory, and mevalonate-suppressive pathways. However, information pertaining to its mechanism of actions is superficial and warrants further studies. As a conclusion, tocotrienol could serve as a functional food component to prevent male osteoporosis, but its application requires validation from a clinical trial in men.

Obesity is a major risk factor for diabetes, and these two metabolic conditions cause significant healthcare burden worldwide. Chronic inflammation and increased oxidative stress due to exposure of cells to excess nutrients in obesity may trigger insulin resistance and pancreatic β-cell dysfunction. Tocotrienol, as a functional food component with anti-inflammatory, antioxidant, and cell signaling-mediating effects, may be a potential agent to complement the current management of obesity and diabetes. The review aimed to summarize the current evidence on the anti-obesity and antidiabetic effects of tocotrienol. Previous studies showed that tocotrienol could suppress adipogenesis and, subsequently, reduce body weight and fat mass in animals. This was achieved by regulating pathways of lipid metabolism and fatty acid biosynthesis. It could also reduce the expression of transcription factors regulating adipogenesis and increase apoptosis of adipocytes. In diabetic models, tocotrienol was shown to improve glucose homeostasis. Activation of peroxisome proliferator-activated receptors was suggested to be responsible for these effects. Tocotrienol also prevented multiple systemic complications due to obesity and diabetes in animal models through suppression of inflammation and oxidative stress. Several clinical trials have been conducted to validate the antidiabetic of tocotrienol, but the results were heterogeneous. There is no evidence showing the anti-obesity effects of tocotrienol in humans. Considering the limitations of the current studies, tocotrienol has the potential to be a functional food component to aid in the management of patients with obesity and diabetes., Competing Interests: The authors declare no conflicts of interest.

Supercritical fluid carbon dioxide (SF-CO₂) was used to extract oil from Elaeagnus mollis Diels ( E. mollis Diels) seed and its antioxidant ability was also investigated. The effect of extraction pressure (20⁻35 MPa), extraction temperature (35⁻65 C), extraction time (90⁻180 min) and seed particle size (40⁻100 mesh) on the oil yield were studied. An orthogonal experiment was conducted to determine the best operating conditions for the maximum extraction oil yield. Based on the optimum conditions, the maximum yield reached 29.35% at 30 MPa, 50 C, 150 min, 80 mesh seed particle size and 40 g/min SF-CO 2 flow rate. The E. mollis Diels seed (EDS) oil obtained under optimal SF-CO 2 extraction conditions had higher unsaturated fatty acid content (91.89%), higher vitamin E content (96.24 ± 3.01 mg/100 g) and higher total phytosterols content (364.34 ± 4.86 mg/100 g) than that extracted by Soxhlet extraction (SE) and cold pressing (CP) methods. The antioxidant activity of the EDS oil was measured by DPPH and hydroxyl radical scavenging test. EDS oil extracted by different methods exhibited a dose-dependent antioxidant ability, with IC 50 values of no significant differences. Based on the results of correlation between bioactive compounds, lupeol and -tocopherol was the most important antioxidant in EDS oil., Competing Interests: The authors declare no conflict of interest.

Tocotrienols, found in several natural sources such as rice bran, annatto seeds, and palm oil have been reported to exert various beneficial health promoting properties especially against chronic diseases, including cancer. The incidence of cancer is rapidly increasing around the world not only because of continual aging and growth in global population, but also due to the adaptation of Western lifestyle behaviours, including intake of high fat diets and low physical activity. Tocotrienols can suppress the growth of different malignancies, including those of breast, lung, ovary, prostate, liver, brain, colon, myeloma, and pancreas. These findings, together with the reported safety profile of tocotrienols in healthy human volunteers, encourage further studies on the potential application of these compounds in cancer prevention and treatment. In the current article, detailed information about the potential molecular mechanisms of actions of tocotrienols in different cancer models has been presented and the possible effects of these vitamin E analogues on various important cancer hallmarks, i.e., cellular proliferation, apoptosis, angiogenesis, metastasis, and inflammation have been briefly analyzed.

A kinetic study of the reaction of singlet oxygen ( 1 O 2 ) with eight vegetable oils 1-8 containing different concentrations of tocopherols (Tocs) and tocotrienols (Toc-3s) was performed. The second-order rate constants (k Q ) for the reaction of 1 O 2 with vegetable oils 1-8 (rice bran, perilla, rape seed, safflower, grape seed, sesame, extra virgin olive, and olive oils) were measured in ethanol/chloroform/D 2 O (50:50:1, v/v/v) solution at 35°C using UV-vis spectrophotometry. Furthermore, comparisons of k Q values determined for the above oils 1-8 with the sum of the product {∑k Q AO-i [AO-i]/10 5 } of the k Q AO-i values obtained for each antioxidant (AO-i) and concentration (in mg/100 g) ([AO-i]/10 5 ) of AO-i (Tocs and Toc-3s) contained in the oils 1-8 were performed. The observed k Q values were not reproduced by the k Q values calculated using only the concentrations of the four Tocs and Toc-3s. These results suggest that the contribution of fatty acids contained in the oils 1-8 is also necessary to fully explain the k Q values. Recently, the second-order rate constants (k S ) for the reaction of aroxyl radical (ArO・) with the same vegetable oils 1-8 were measured in the same solvent at 25℃ using stopped-flow spectrophotometry (Ref. 23). The k S values obtained could be well explained as the sum of the product {Σ k S AO-i [AO-i]/10 5 } of the k S AO-i and the [AO-i]/10 5 of AO-i (Tocs and Toc-3s) contained in the vegetable oils.

Background: Tocotrienols (TTs) are vitamin E derivatives naturally occurring in several plants and vegetable oils. Like Tocopherols (TPs), they comprise four isoforms, α, β, γ and δ, but unlike TPs, they present an unsaturated isoprenoid chain. Recent studies indicate that TTs provide important health benefits, including neuroprotective, anti-inflammatory, anti-oxidant, cholesterol lowering and immunomodulatory effects. Moreover, they have been found to possess unique anti-cancer properties., Objective: The purpose of this review is to present an overview of the state of the art of TTs role in cancer prevention and treatment, as well as to describe recent patents proposing new methods for TTs isolation, chemical modification and use in cancer prevention and/or therapy., Methods: Recent literature and patents focusing on TTs anti-cancer applications have been identified and reviewed, with special regard to their scientific impact and novelty., Results: TTs have demonstrated significant anti-cancer activity in multiple tumor types, both in vitro and in vivo. Furthermore, they have shown synergistic effects when given in combination with standard anti-cancer agents or other anti-tumor natural compounds. Finally, new purification processes and transgenic sources have been designed in order to improve TTs production, and novel TTs formulations and synthetic derivatives have been developed to enhance their solubility and bioavailability., Conclusion: The promising anti-cancer effects shown by TTs in several preclinical studies may open new opportunities for therapeutic interventions in different tumors. Thus, clinical trials aimed at confirming TTs chemopreventive and tumor-suppressing activity, particularly in combination with standard therapies, are urgently needed., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

The Cosmetic Ingredient Review (CIR) Expert Panel (Panel) assessed the safety of 14 tocopherols and tocotrienols and concluded these ingredients are safe as used in cosmetics. The tocopherols are reported to function in cosmetics as antioxidants or skin-conditioning agents; in contrast, tocotrienols are not reported to function as an antioxidants in cosmetics but as a light stabilizer, oral care agent, or skin-conditioning agent. The Panel reviewed the new and existing animal and clinical data to determine the safety of these ingredients and found it appropriate to extrapolate the existing information to conclude on the safety of all the tocopherols and tocotrienols.

Non-enzymatic glycation mediated advanced glycation end products (AGEs) generation results in the pathogenesis of diabetic complications and atherosclerotic cardiovascular disease (ASCVD) which is greatly influenced by 3-hydroxy-3-methyl-glutaryl Co-A reductase (HMG-R) activity. HMG-R inhibitors, statins, are well known for reducing mortality and morbidity of ASCVD in patients with diabetes due to their pleiotropic effects independent of cholesterol lowering. Due to distinct chemical structures, various statins may play important role in the inhibition of AGEs mediated pathologies. Herein, we evaluated the anti-glycating potential of atorvastatin (AT), rosuvastatin (RT), pitavastatin (PT), fluvastatin (FT), simvastatin (ST) alone as well in combination with ezetimibe (EZ) and tocotrienol (TT) against d-ribose mediated BSA and LDL glycation by various physicochemical approaches. Our data suggested that AT, TT, RT, EZ, EZ-AT, and EZ-RT were able to substantially inhibit the AGEs formation via modulation of hyperchromicity, fluorogenic AGEs, % contribution of α-helix and β-sheets to protein secondary structure, amide-I band stretching, carbonyl and HMF content in Gly-BSA as well as Gly-LDL. On the basis of above findings, we concluded that HMG-R inhibitors and TT, alone or in combination with EZ, may be established as terrific therapeutic agents for the patients suffering from AGEs induced diabetic cum ASCVD complications., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Red palm oil (RPO) is a natural source of Vitamin E (70-80% tocotrienol). It is a potent natural antioxidant that can be used in skin-care products. Its antioxidant property protects skin from inflammation and aging. In our work, a tocotrienol-rich RPO-based nanoemulsion formulation was optimized using response surface methodology (RSM) and formulated using high pressure homogenizer. Effect of the concentration of three independent variables [surfactant (5-15 wt%), co-solvent (10-30 wt%) and homogenization pressure (500-700 bar)] toward two response variables (droplet size, polydispersity index) was studied using central composite design (CCD) coupled to RSM. RSM analysis showed that the experimental data could be fitted into a second-order polynomial model and the coefficients of multiple determination (R2) is 0.9115. The optimized formulation of RPO-based nanoemulsion consisted of 6.09 wt% mixed surfactant [Tween 80/Span 80 (63:37, wt)], 20 wt% glycerol as a co-solvent via homogenization pressure (500 bar). The optimized tocotrienol-rich RPO-based nanoemulsion response values for droplet size and polydispersity index were 119.49nm and 0.286, respectively. The actual values of the formulated nanoemulsion were in good agreement with the predicted values obtained from RSM, thus the optimized compositions have the potential to be used as a nanoemulsion for cosmetic formulations., Competing Interests: The authors have declared that no competing interests exist.

Chronic hyperglycemia induces impairment of muscle growth and development of diabetes mellitus (DM). Since skeletal muscle is the major site for disposal of ingested glucose, impaired glucose metabolism causes imbalance between protein synthesis and degradation which adversely affects physical mobility. In this study, we investigated the effect of tocotrienol-rich fraction (TRF) supplementation on skeletal muscle damage in diabetic mice. Diabetes was induced by a high-fat diet with streptozotocin (STZ) injection (100 mg/kg) in male C57BL/6J mice. After diabetes was induced (fasting blood glucose levels≥250 mg/dl), normal control (CON) and diabetic control (DMC) groups were administrated with olive oil, while TRF treatment groups were administrated with TRF (dissolved in olive oil) at low dose (100 mg/kg BW, LT) or high dose (300 mg/kg BW, HT) by oral gavage for 12 weeks. TRF supplementation ameliorated muscle atrophy, plasma insulin concentration and homeostatic model assessment estimated insulin resistance in diabetic mice. Moreover, TRF treatment up-regulated IRS-1 and Akt levels accompanied by increased translocation of GLUT4. Furthermore, TRF increased mitochondrial biogenesis by activating SIRT1, SIRT3 and AMPK in diabetic skeletal muscle. These changes were in part mechanistically explained by reduced levels of skeletal muscle proteins related to oxidative stress (4-hydroxynonenal, protein carbonyls, Nrf2 and HO-1), inflammation (NFkB, MCP-1, IL-6 and TNF-α), and apoptosis (Bax, Bcl₂ and caspase-3) in diabetic mice. Taken together, these results suggest that TRF might be useful as a beneficial nutraceutical to prevent skeletal muscle atrophy associated with diabetes by regulating insulin signaling via AMPK/SIRT1/PGC1α pathways in type 2 diabetic mice., (Copyright © 2018 Elsevier Inc. All rights reserved.)

In this work, we report a rapid and convenient HPLC-UV-DAD method for the isolation of δ-T3 on semi-preparative scale from two different vitamin E rich processed, commercially available products obtained from the fruits of Elaeis guineensis Jacq. (oil palm) and from the seeds of Bixa orellana L. (achiote tree). Chromatography was run using reverse phase (RP) C-18 columns and HPLC-grade acetonitrile as mobile phase. The purity of the isolated δ-T3, assessed by GC-MS and 1 H NMR was above 98%. The δ-T3 cytotoxic activity found in vitro against the proliferation of human A375 melanoma cells compared to that of the other δ-T3 free tocols mixture suggest its primary role in the experimental anticancer activity observed for palm oil derived products. Taken altogether, the results of this study highlight the importance of the application of suitable purification systems for the preparations of tocotrienols prior to their experimental or clinical testing.

Background: Patients receiving androgen deprivation therapy experience secondary hypogonadism, associated bone loss, and increased fracture risk. It has been shown that tocotrienol from Bixa orellana (annatto) prevents skeletal microstructural changes in rats experiencing primary hypogonadism. However, its potential in preventing bone loss due to androgen deprivation therapy has not been tested. This study aimed to evaluate the skeletal protective effects of annatto tocotrienol using a buserelin-induced osteoporotic rat model., Methods: Forty-six male Sprague Dawley rats aged 3 months were randomized into six groups. The baseline control (n=6) was sacrificed at the onset of the study. The normal control (n=8) received corn oil (the vehicle of tocotrienol) orally daily and normal saline (the vehicle of buserelin) subcutaneously daily. The buserelin control (n=8) received corn oil orally daily and subcutaneous buserelin injection (75 µg/kg) daily. The calcium control (n=8) was supplemented with 1% calcium in drinking water and daily subcutaneous buserelin injection (75 µg/kg). The remaining rats were given daily oral annatto tocotrienol at 60 mg/kg (n=8) or 100 mg/kg (n=8) plus daily subcutaneous buserelin injection (75 µg/kg) (n=8). At the end of the experiment, the rats were euthanized and their blood, tibia, and femur were harvested. Structural changes of the tibial trabecular and cortical bone were examined using X-ray micro-computed tomography. Femoral bone calcium content and biomechanical strength were also evaluated., Results: Annatto tocotrienol at 60 and 100 mg/kg significantly prevented the deterioration of trabecular bone and cortical thickness in buserelin-treated rats ( P <0.05). Both doses of annatto tocotrienol also improved femoral biomechanical strength and bone calcium content in buserelin-treated rats ( P <0.05). The effects of annatto tocotrienol were comparable to calcium supplementation., Conclusion: Annatto tocotrienol supplementation is effective in preventing degeneration of the bone induced by buserelin. Therefore, it is a potential antiosteoporotic agent for men receiving androgen deprivation therapy., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

This investigation aimed to evaluate the chemical composition and physicochemical properties of seed oils from 6 date palm (Phoenix. dactylifera L.) cultivars (Barhi, Khalas, Manifi, Rezeiz, Sulaj, and Sukkari) growing in Saudi Arabia and to compare them with conventional palm olein. The mean oil content of the seeds was about 7%. Oleic acid (48.67%) was the main fatty acid, followed by lauric acid (17.26%), stearic acid (10.74%), palmitic acid (9.88%), and linolenic acid (8.13%). The mean value for free fatty acids content was 0.5%. The P. dactylifera seed oil also exhibited a mean tocol content of 70.75 mg/100 g. α-Tocotrienol was the most abundant isomer (30.19%), followed by γ-tocopherol (23.61%), γ-tocotrienol (19.07%), and α-tocopherol (17.52%). The oils showed high thermal and oxidative stabilities. The findings indicate that date seed oil has the potential to be used in the food industry as an abundant alternative to palm olein., Practical Application: This study showed that date seed had great nutritional value due to which it can be used for food applications especially as frying or cooking oil. In addition, date oil has also potential to be used in cosmetic and pharmaceutical practices as well. The extraction of oil from Phoenix dactylifera seed on large scale can create positive socioeconomic benefits especially for rural communities and could also assist to resolve the environmental issues generated by excess date production in large scale date-producing countries such as Saudi Arabia., (© 2018 Institute of Food Technologists®.)

Tocotrienol microcapsules (TM) were formed by firstly preparing Pickering emulsion containing tocotrienols, which was then gelled into microcapsules using alginate and chitosan. In this study, we examined the stability of TM during storage and when applied into a model food system, i.e. yogurt. During storage at 40°C, TM displayed remarkably lower tocotrienols loss (50.8%) as compared to non-encapsulated tocotrienols in bulk oil (87.5%). When the tocotrienols were incorporated into yogurt, the TM and bulk oil forms showed a loss of 23.5% and 81.0%, respectively. Generally, the tocotrienols were stable in the TM form and showed highest stability when these TM were added into yogurt. δ-Tocotrienol was the most stable isomer in both forms during storage and when incorporated into yogurt. The addition of TM into yogurt caused minimal changes in the yogurt's color and texture but slightly altered the yogurt's viscosity., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Annatto tocotrienols (AnT3), which contain approximately 90% δ-tocotrienol (δ-T3), were added to mid-oleic sunflower oil used for frying tortilla chips over 3 d. The objectives were to evaluate their stability during frying, absorption by the fried food, and activity as antioxidants in frying oil and in tortilla chips during storage. AnT3 did not significantly affect the stability of the oil during frying or the sensory profiles of freshly fried chips. The naturally present α-tocopherol (α-T) in the oil degraded at a lower rate in the presence of AnT3, resulting in significantly higher α-T by the end of the frying study. Levels of tocopherols and tocotrienols in the chips mirrored oil levels. AnT3 did not affect the sensory profile of the chips after 1 wk of storage at 50 °C, but after 3 wk of storage, the control chips had higher levels of painty and rancid flavors compared to chips with AnT3. Headspace hexanal was also significantly higher in the control chips compared to the chips with AnT3 after 3 wk of storage., Practical Application: Annatto tocotrienols, containing primarily delta- and gamma-tocotrienols, were added to mid-oleic sunflower oil used for frying tortilla chips. The tocotrienols were absorbed by the chips along with the oil. They slowed the degradation of α tocopherol during frying, and reduced levels of painty and rancid flavor scores as well as headspace hexanal in chips that were stored for 3 wk at elevated temperatures. The results indicated that fried snack foods such as tortilla chips may be a suitable and convenient vehicle for enriching tocotrienols in the diet, and that tocotrienols may also enhance the shelf-life of fried foods., (© 2018 Institute of Food Technologists®.)

Vitamin E TPGS is a tocopherol (α-T) based nonionic surfactant that was used in the formulation of the Tocosol™ paclitaxel nanoemulsion, which was withdrawn from phase III clinical trials. Unlike tocopherols, however, the tocotrienol (T 3 ) isomers of vitamin E were found to have innate anticancer activity and were shown to potentiate the antitumor activity of paclitaxel. The primary objective of the present study was therefore to develop a paclitaxel nanoemulsions by substituting α-T oil core of Tocosol™ with γ-T 3 in, and vitamin E TPGS with PEGylated γ-T 3 as the shell, and test the nanoemulsions against Bx-PC-3 and PANC-1 pancreatic tumor cells. A secondary objective was to test the activity of paclitaxel when directly conjugated with the γ-T 3 isomer of vitamin E. The synthesis of the conjugates was confirmed by NMR and mass spectroscopy. Developed nanoemulsions were loaded with free or lipid conjugated paclitaxel. Nanoemulsions droplets were <300 nm with fastest release observed with formulations loaded with free paclitaxel when γ-T 3 was used as the core. Substituting α-T with γ-T 3 was also found to potentiate the anticancer activity of the nanoemulsions. Although marginal increase in activity was observed when nanoemulsions were loaded with free paclitaxel, a significant increase in activity was observed when lipid conjugates were used. The results from this study suggest that the developed paclitaxel nanoemulsions with either γ-T 3 , PEGylated γ-T 3 , or paclitaxel lipid conjugates may represent a more promising option for paclitaxel delivery in cancer chemotherapy., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The literature review systematizes a lot of information on the biological effects of tocotrienols. The effects are described in more details. Vitamin E was discovered at 20s of the last century, but tocotrienols are a less studied part of it. Tocotrienols exhibit cardioprotective, lipid-lowering, antitumor, anti-inflammatory, neuroprotective properties as it has been shown by recent researches. Edible oils (e.g. palm oil, rice bran oil, barley oil, etc.) contain high level of tocotrienols. So, after extraction from plant raw materials they can be used for long-term preventive therapy of many diseases, as well as for the treatment and enhancement of the action of medicinal substances. They can also be used as functional ingredients to stabilize and extend the shelf-life of food products due to their antioxidant properties., (Copyright© GEOTAR-Media Publishing Group.)

We previously found that antioxidative activity of liposomes co-encapsulating astaxanthin (Asx) and tocotrienols (T3s) was higher than the calculated additive activity, which results from intermolecular interactions between both antioxidants (J. Clin. Biochem. Nutr., 59, 2016, Kamezaki et al.). Herein, we conducted experiments to optimize Asx/α-T3 ratio for high antioxidative activity, and tried to elucidate details of intermolecular interaction of Asx with α-T3. Higher activity than calculated additive value was clearly observed at an Asx/α-T3 ratio of 2 : 1, despite two α-T3 would potentially interact with two terminal rings of one Asx. The synthetic Asx used in this study was a mixture of three stereoisomers, 3R,3'R-form (Asx-R), 3S,3'S-form (Asx-S) and 3R,3'S-meso form (Asx-meso). The calculated binding energy of the Asx-S/α-T3 complex was higher than those of Asx-R/α-T3 and Asx-meso/α-T3, suggesting that Asx-S and α-T3 is the most preferable combination for the intermolecular interaction. The optimal Asx-S/α-T3 ratio for antioxidation was shown to be 1 : 2. These results suggest that the Asx stereochemistry affects the intermolecular interaction of Asx/α-T3. Moreover, the absorption spectrum changes of Asx-S upon co-encapsulation with α-T3 in liposomes indicate that the electronic state of Asx-S is affected by intermolecular interactions with α-T3. Further, intermolecular interactions with α-T3 affected the electronic charges on the C9, C10 and C15 atoms in the polyene moiety of Asx-S. In conclusion, the intermolecular interaction of Asx/T3 depends on the Asx stereochemistry, and caused a change in the electronic state of the Asx polyene moiety by the presence of double bond in the T3 triene moiety.

Tocopherols and tocotrienols, collectively known as vitamin E, have received a great deal of attention because of their interesting biological activities. In the present study, we reexamined and improved previous methods of sample preparation and the conditions of high-performance liquid chromatography for more accurate quantification of tocopherols, tocotrienols and their major chain-degradation metabolites. For the analysis of serum tocopherols/tocotrienols, we reconfirmed our method of mixing serum with ethanol followed by hexane extraction. For the analysis of tissue samples, we improved our methods by extracting tocopherols/tocotrienols directly from tissue homogenate with hexane. For the analysis of total amounts (conjugated and unconjugated forms) of side-chain degradation metabolites, the samples need to be deconjugated by incubating with β-glucuronidase and sulfatase; serum samples can be directly used for the incubation, whereas for tissue homogenates a pre-deproteination step is needed. The present methods are sensitive, convenient and are suitable for the determination of different forms of vitamin E and their metabolites in animal and human studies. Results from the analysis of serum, liver, kidney, lung and urine samples from mice that had been treated with mixtures of tocotrienols and tocopherols are presented as examples., (Copyright © 2017. Published by Elsevier B.V.)

Considering the health benefits of tocotrienols, continuous works have been done on the encapsulation and delivery of these compounds. In this study, we encapsulated tocotrienols in chitosan-alginate microcapsules and evaluated their release profile. Generally, these tocotrienols microcapsules (TM) displayed high thermal stability. When subjected to pH adjustments (pH 1-9), we observed that the release of tocotrienols was the highest (33.78 ± 0.18%) under basic conditions. The TM were also unstable against the effect of ionic strength, with a high release (70.73 ± 0.04%) of tocotrienols even at a low sodium chloride concentration (50 mM). As for the individual isomers, δ-tocotrienol was the most sensitive to pH and ionic strength. In contrast, β-/γ-tocotrienols were the most ionic-stable isomers but more responsive toward thermal treatment. Simulated gastrointestinal model showed that the chitosan-alginate-based TM could be used to retain tocotrienols in the gastric and subsequently release them in the intestines for possible absorption.

Aim: To develop 6-O-palmitoyl-ascorbic acid-based niosomes targeted to transferrin receptor for intravenous administration of tocotrienols (T3) in breast cancer., Materials & Methods: Niosomes were prepared using film hydration and ultrasonication methods. Transferrin was coupled to the surface of niosomes via chemical linker. Nanovesicles were characterized for size, zeta potential, morphology, stability and biological efficacy., Results: When evaluated in MDA-MB-231 cells, entrapment of T3 in niosomes caused 1.5-fold reduction in IC 50 value compared with nonformulated T3. In vivo, the average tumor volume of mice treated with tumor-targeted niosomes was 12-fold lower than that of untreated group, accompanied by marked downregulation of three genes involved in metastasis., Conclusion: Findings suggested that tumor-targeted niosomes served as promising delivery system for T3 in cancer therapy.

Palm oil is one of the richest sources of tocotrienols and may contain other non-tocopherol vitamin E congeners. The vitamin E profiles of fully ripened fruit mesocarp of three Elaeis guineensis, two Elaeis oleifera, and one hybrid O × G palm fruit genotypes from Costa Rica were analyzed by high-performance liquid chromatography with fluorescence detection and gas chromatography-mass spectrometry after mechanical extraction by a screw press and chemical extraction with hexane. γ-Tocotrienol, α-tocotrienol, and α-tocopherol were the most abundant tocochromanols, while other tocopherols (β-tocopherol, γ-tocopherol, and δ-tocopherol) and α-tocomonoenol were detected at minor concentrations. Significant differences in vitamin E profiles between genotypes were observed, and the variety E. oleifera Quepos (CB9204) had by far the highest content of total tocotrienols (890 μg/g of oil) and total vitamin E (892 μg/g of oil). Chemical extraction with hexane afforded up to 2.5-fold higher vitamin E yields than screw press extraction. α-Tocomonoenol co-eluted with γ-tocopherol in reversed-phase high-performance liquid chromatography analyses and is a possible source of error in the quantification of γ-tocopherol in foods.

There are six tocol analogs present in palm oil, namely α-tocopherol (α-T), α-tocomonoenol (α-T₁), α-tocotrienol (α-T₃), γ-tocotrienol (γ-T₃), β-tocotrioenol (β-T₃) and δ-tocotrienol (δ-T₃). These analogs were difficult to separate chromatographically due to their similar structures, physical and chemical properties. This paper reports on the effect of pressure and injection solvent on the separation of the tocol analogs in palm oil. Supercritical CO₂ modified with ethanol was used as the mobile phase. Both total elution time and resolution of the tocol analogs decreased with increased pressure. Ethanol as an injection solvent resulted in peak broadening of the analogs within the entire pressure range studied. Solvents with an eluent strength of 3.4 or less were more suitable for use as injecting solvents., Competing Interests: The authors declare no conflict of interest.

Isolation of lipophilic compounds by countercurrent chromatography (CCC) is a challenge because biphasic solvent systems in which these compounds distribute evenly are difficult to obtain. In this article we present novel applications of lipid compound isolation from natural sources. Conjugated linolenic acids (CLnAs, log K OW ∼7) were isolated from pomegranate oil using a solvent system consisting of n-heptane/methanol/water 100:91:9 (v/v/v). The CLnA fraction was free of other fatty acids but consisted of different isomers which were not resolved from each other. In the less polar range (log K OW ∼12), three tocotrienols (α-, γ- and δ-tocotrienol) were isolated from a vitamin E capsule produced from palm oil by using the solvent system n-hexane/acetonitrile/benzotrifluoride (BTF) at a ratio of 10:6.5:3.5 (v/v/v). Between 36 and 65mg of each of the three tocotrienols were obtained in one injection with purities >97%. Advantages and disadvantages of the "BTF system" are discussed by comparing the phase composition with the simple n-hexane/acetonitrile system and by the fractionation of phytosterols (log K OW ∼9.5) from rapeseed oil., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The present investigation was conducted to study the true retentions of α-tocopherol, tocotrienols and β-carotene in crown daisy, unripe hot pepper, onion, garlic, and red pepper as affected by various domestic cooking methods, those were, boiling, baking, stir-frying, deep-frying, steaming, roasting, and microwaving. Fatty acid compositions were determined by GC, and HPLC were used for quantification of α-tocopherol, tocotrienols, and β-carotene. True retentions of α-tocopherol in cooked foods were as follows: boiling (77.74-242.73%), baking (85.99-212.39%), stir-frying (83.12-957.08%), deep-frying (162.48-4214.53%), steaming (45.97-179.57%), roasting (49.65-253.69%), and microwaving (44.67-230.13%). Similarly for true retention of β-carotene were: boiling (65.69-313.75%), baking (71.46-330.16%), stir-frying (89.62-362.46%), deep-frying (178.22-529.16%), steaming (50.39-240.92%), roasting (73.54-361.47%), and microwaving (78.60-339.87%).

Vitamin E refers to a group of saturated tocopherol (T) isomers and the biologically more active unsaturated tocotrienol (T 3 ) isomers. PEGylated α-tocopherol, commercially known as Vitamin E TPGS, has been used as an emulsifier and therapeutic agent for children with vitamin E deficiency. Limited information, however, is available about the PEG conjugates of the tocotrienol isomers of vitamin E. The current work was therefore undertaken to synthesize and characterize the water soluble polyethylene glycol (PEG 350 and 1000) derivatives of T and T 3 . Yield and the identity of the synthesized products were confirmed by 1 H NMR, mass spectroscopy, HPLC, and thermal analysis. The self-assembly of the PEGylated vitamin E isomers in water at critical micelle concentrations (CMC) was further confirmed by size, zeta, and Cryo-TEM image analysis. While stable at pH 7.4, PEG conjugates were found to rapidly hydrolyze at pH 1.2. Our data showed that PEGylated T 3 isomers were significantly more active as inhibitors for P-glycoprotein than PEGylated T. The in vitro cytotoxicity of the conjugates was also tested against a large panel of normal and tumorigenic cells. Of the conjugates, γ-T 3 PGS 1000 and δ-T 3 PGS 1000 were found to have the least toxicity against non-tumorigenic breast and pancreatic cell lines, which may be advantageous for its use as functional excipients in drug delivery. The results from the current work have demonstrated the feasibility of synthesizing PEGylated conjugates of vitamin E isomers and highlighted the potential use of these conjugates in drug delivery as functional and safer excipients especially for γ-T 3 PGS 1000 and δ-T 3 PGS 1000 conjugate., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Vitamin E is recognized as an essential vitamin since its discovery in 1922. Most vegetable oils contain a mixture of tocopherols and tocotrienols in the vitamin E composition. Structurally, tocopherols and tocotrienols share a similar chromanol ring and a side chain at the C-2 position. Owing to the three chiral centers in tocopherols, they can appear as eight different stereoisomers. Plant sources of tocopherol are naturally occurring in the form of RRR while synthetic tocopherols are usually in the form of all-racemic mixture. Similarly, with only one chiral center, natural tocotrienols occur as the R -isoform. In this review, we aim to discuss a few chromatographic methods that had been used to separate the stereoisomers of tocopherols and tocotrienols. These methods include high performance liquid chromatography, gas chromatography and combination of both. The review will focus on method development including selection of chiral columns, detection method and choice of elution solvent in the context of separation efficiency, resolution and chiral purity. The applications for separation of enantiomers in vitamin E will also be discussed especially in terms of the distinctive biological potency among the stereoisoforms.

Tocotrienols are forms of vitamin E that are present in several important food crops. Compared to tocopherols, less research has been conducted on these compounds because of their low bioavailability and distribution in plant tissues. Both tocotrienols and tocopherols are known for their antioxidant and anticancer activities, which are beneficial for both humans and animals. Moreover, tocotrienols possess certain properties which are not found in tocopherols, such as neuroprotective and cholesterol-lowering activities. The contents of tocotrienols in plants vary. Tocotrienols constitute more than 70% and tocopherols less than 30% of the total vitamin E content in palm oil, which is the best source of vitamin E. Accumulation of tocotrienols also occurs in non-photosynthetic tissues, such as the seeds, fruits and latex of some monocotyledonous and dicotyledonous plant species. The use of biotechnological techniques to increase the tocotrienol content in plants, their biological functions, and benefits to human health are discussed in this review.

Objective: This review examines various aspects of vitamin E, both in plant metabolism and with regard to its importance for human health. Vitamin E is the collective name of a group of lipidsoluble compounds, chromanols, which are widely distributed in the plant kingdom. Their biosynthetic pathway, intracellular distribution and antioxidant function in plants are well recognized, although their other functions are also considered., Conclusion: Analytical methods for the determination of vitamin E are discussed in detail. Furthermore, the vitamin E metabolism and its antioxidant action in humans are described. Other nonantioxidant functions of vitamin E are also presented, such as its anti-inflammatory effects, role in the prevention of cardiovascular diseases and cancer, as well as its protective functions against neurodegenerative and other diseases., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Diabetes mellitus is characterized by hyperglycemia and capillary hypoxia that causes excessive production of free radicals and impaired antioxidant defense, resulting in oxidative stress and diabetes complications such as impaired wound healing. We have previously shown that modified forms of tocotrienols possess beneficial effects on the biosynthesis of the mevalonate pathway lipids including increase in mitochondrial CoQ. The aim of this study is to investigate the effects of mono-epoxy-tocotrienol-α on in vitro and in vivo wound healing models as well as its effects on mitochondrial function. Gene profiling analysis and gene expression studies on HepG2 cells and human dermal fibroblasts were performed by microarray and qPCR, respectively. In vitro wound healing using human fibroblasts was studied by scratch assay and in vitro angiogenesis using human dermal microvascular endothelial cells was studied by the tube formation assay. In vivo wound healing was performed in the diabetic db/db mouse model. For the study of mitochondrial functions and oxygen consumption rate Seahorse XF-24 was employed. In vitro, significant increase in wound closure and cell migration (p<0.05) both in normal and high glucose and in endothelial tube formation (angiogenesis) (p<0.005) were observed. Microarray profiling analysis showed a 20-fold increase of KIF26A gene expression and 11-fold decrease of lanosterol synthase expression. Expression analysis by qPCR showed significant increase of the growth factors VEGFA and PDGFB. The epoxidated compound induced a significantly higher basal and reserve mitochondrial capacity in both HDF and HepG2 cells. Additionally, in vivo wound healing in db/db mice, demonstrated a small but significant enhancement on wound healing upon local application of the compound compared to treatment with vehicle alone. Mono-epoxy-tocotrienol-α seems to possess beneficial effects on wound healing by increasing the expression of genes involved in cell growth, motility and angiogenes as well as on mitochondrial function., (Copyright © 2017 Elsevier Inc. All rights reserved.)