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Novel SARS-CoV-2 claimed a large number of human lives. The main proteins for viral entry into host cells are SARS-CoV-2 spike glycoprotein (PDB ID: 6VYB) and spike receptor-binding domain bound with ACE2 (spike RBD-ACE2; PDB ID: 6M0J). Currently, specific therapies are lacking globally. This study was designed to investigate the bioactive components from Moringa oleifera leaf (MOL) extract by gas chromatography-mass spectroscopy (GC-MS) and their binding interactions with spike glycoprotein and spike RBD-ACE2 protein through computational analysis. GC-MS-based analysis unveiled the presence of thirty-seven bioactive components in MOL extract, viz. polyphenols, fatty acids, terpenes/triterpenes, phytosterols/steroids, and aliphatic hydrocarbons. These bioactive phytoconstituents showed potential binding with SARS-CoV-2 spike glycoprotein and spike RBD-ACE2 protein through the AutoDock 4.2 tool. Further by using AutoDock 4.2 and AutoDock Vina, the top sixteen hits (binding energy ≥ - 6.0 kcal/mol) were selected, and these might be considered as active biomolecules. Moreover, molecular dynamics simulation was determined by the Desmond module. Interestingly two biomolecules, namely β-tocopherol with spike glycoprotein and β-sitosterol with spike RBD-ACE2, displayed the best interacting complexes and low deviations during 100-ns simulation, implying their strong stability and compactness. Remarkably, both β-tocopherol and β-sitosterol also showed the drug- likeness with no predicted toxicity. In conclusion, these findings suggested that both compounds β-tocopherol and β-sitosterol may be developed as anti-SARS-CoV-2 drugs. The current findings of in silico approach need to be optimized using in vitro and clinical studies to prove the effectiveness of phytomolecules against SARS-CoV-2.

The relationship of dietary vitamin E intake with incident chronic kidney disease (CKD) was not clear as yet. We aimed to examine the associations of dietary total vitamin E and tocopherol isoforms intakes with incident CKD in a 30-year follow-up study from young adulthood to midlife.A total of 4038 American adults aged 18-30 years and without reduced estimated glomerular filtration rate (eGFR) were enrolled from Coronary Artery Risk Development in Young Adults study. Diet was evaluated by a validated dietary-history questionnaire at baseline, and after 7 and 20 years later. The study outcome was incident CKD, defined as an eGFR60 mL/min/1.73 mDuring a 30-year follow-up, 642 (15.9%) participants developed incident CKD. Overall, there was a L-shaped relationship between dietary total vitamin E intake and incident CKD (P for non-linearity0.001). When total vitamin E intake was assessed as quartiles, compared with those in the first quartile (4.35 mg α-TE/1000 kcal), the adjusted HRs (95%CI) of incident CKD for participants in the fourth quartile (≥9.61 mg α-TE/1000 kcal) was 0.55 (0.40, 0.75). Moreover, higher intakes of beta-tocopherol and gamma-tocopherol were significantly associated with a lower incident CKD. Higher intake of delta-tocopherol was significantly related to a higher incident CKD. And there was no obvious association of alpha-tocopherol intake with incident CKD.There were inverse associations of total vitamin E, beta-tocopherol and gamma-tocopherol intakes, a positive association of delta-tocopherol intake, and no obvious association of alpha-tocopherol intake, with incident CKD among American adults.

For simultaneous analysis of four fat-soluble tocopherols (α-, β-, γ-, and δ-) in edible oils, an efficient and green method using deep eutectic solvent-based liquid-phase microextraction (DES-LPME) coupled with reversed-phase high-performance liquid chromatography (RP-HPLC) was developed. The DESs formed by different quaternary ammonium salts and ethanol were used as the extractants. Tetrabutylammonium chloride (TBAC)-ethanol DES at a molar ratio of 1:2 achieved the best extraction efficiency. Under the optimized conditions, the detection limits were in the range of 2.1–3.0 ng mL−1. The intra-day and inter-day repeatability were in the ranges of 3.9–5.3% and 4.8–7.1%, respectively, and the recoveries for the real samples varied from 80.7% to 105.4%. The developed method was successfully employed for the determination of all four tocopherol homologues with an RP-HPLC system containing a COSMOSIL π-NAP column in five edible oils collected locally.

Hellenia speciosa (J.Koenig) S.R.Dutta, is a plant species belonging to the family Costaceae. It is widely distributed in China, India, Malaysia, Indonesia, tropical and subtropical Asia. In Ayurveda, the rhizome of the plant has been extensively used to treat fever, rash, asthma, bronchitis and, intestinal worms. The objective of the present study was to investigate the phytochemical constituents of the leaf of Hellenia speciosa using Gas Chromatography and Mass Spectroscopy analysis (GC-MS). The GC-MS analysis revealed the presence of 17 phytochemical components in the ethanolic leaf extract of Hellenia speciosa. The prevailing bioactive compounds present in Hellenia speciosa were Thymol (RT-10.019;3.59%), Caryophyllene (RT-11.854:0.62%), Caryophyllene oxide (RT-13.919;1.34%), Artumerone (RT-14.795;1.35%), Hexadecanoic acid methyl ester (RT-17.536; 2.77%), 9,12-Octadecanoic acid methyl ester (RT-19.163;1.35%), Squalene (RT- 24.980;1.19%), Piperine (RT-25.745;3.11%), Beta Tocopherol (RT-26.681;2.88%) Vitamin E (RT- 27.290;2.64%), Progesterone (RT-29.608;3.18%), Caparratriene (RT-29.861;9.72%), and Testosterone (RT-30.73;5.81%). The compounds were identified by comparing their retention time and peak area with that of the literature and by interpretation of mass spectra. The results and findings of the present study suggest that the plant can be used as a valuable source in the field of herbal drug discovery. The presence of bioactive compounds justifies the use of plant leaves for treating various diseases with fewer side effects and recommended the plant of pharmaceutical importance. However, further studies are needed to undertake its bioactivity and toxicity profile.

Seeds of 15 diverse rice accessions, representing aus, indica, temperate japonica and tropical japonica subpopulations, were produced under temperate climate conditions in Korea and used for vitamin E analysis and seed storage experiments at 45°C and 10.9% seed moisture content. High γ-tocotrienol was significantly positively correlated with seed longevity. In addition, a high β-tocopherol proportion relative to δ-tocopherol was significantly negatively correlated with seed longevity. Using high-density single-nucleotide polymorphism marker data, DNA haplotype analysis showed clear allelic variations in the region of two S-adenosylmethionine synthetase genes: LOC_Os04g42095 and LOC_Os11g15410, which regulate the conversion of δ-tocopherol into β-tocopherol. Four indica accessions with rare and subpopulation-specific alleles showed a 2.3-fold lower β-/δ-tocopherol ratio compared with accessions from other subpopulations.

OBJECTIVES: The aim of this study was to determine the effect of feeding cats with reduced renal function a high protein food while maintaining phosphorus concentration across foods containing varying protein levels. METHODS: The study was conducted using 23 cats of 5–13 years of age with chronic kidney disease. After a 1 month washout period, cats were randomly assigned to one of the 6 groups of approximately 4 cats to receive 3 treatment foods, each for 111 days, in a sequence following the William's Latin Square design. The treatment foods contained on a dry matter basis, low (25.94%), medium (31.91%) or high (36.77%) protein and had similar other nutrient levels including Phosphorus. Average body weights were determined after each treatment period. Blood and urine samples were collected at the end of each treatment period to compare changes in levels of metabolites associated with progression of kidney disease. RESULTS: The consumption of the foods with different protein levels did not have an effect on body weight. Urine pH was significantly higher after cats were fed high protein food (P = 0.0003). Blood chemistry results showed that cats had significantly increased level of blood urea nitrogen (BUN) after the consumption of the high protein food compared with the low protein food (P = 0.005). Increased urea levels were also confirmed from results of plasma metabolomics. Levels of microbial uremic toxins such as 3-indoxyl sulfate, 5-hydroxyindole sulfate, 6-hydroxyindole sulfate and 3-hydroxyindoline-one sulfate were significantly elevated after cats were fed high protein compared to both medium and low protein foods (P

The oaks Quercus robur L. and Quercus rubra L. are grown worldwide. The oak fruits (acorns) fallen on the ground during the autumn are usually considered as unusable, although some possible applications have been reported. In the present study, the possible recovery of tocopherols from acorns of two oak species Q. rubra (n = 14) and Q. robur (n = 15) was evaluated. Four tocopherols (Ts) (α-T, β-T, γ-T, and δ-T) in the oak fruits of Q. rubra and Q. robur were identified. The Q. robur acorns had abundant γ-T (28.18 ± 6.7 mg/100 g dw), while in Q. rubra β-T was predominant (17.28 ± 2.91 mg/100 g dw), nearly 95 and 90% of total detected tocopherols, respectively. The variability of tocopherol levels within the same species was lower for Q. rubra (16.5%) and higher for Q. robur (23.4%). The principal component analysis, applied to four tocopherol homologues, confirmed their feasibility to distinguish two strictly separated groups: one for species Q. rubra and the other for Q. robur. The predominance of β-T in Q. rubra acorns is a unique finding in the plant world; therefore, acorns of this oak species can be used as an unconventional natural source of this rare tocopherol homologue.

Seed samples of some rape and canola cultivars were analysed for oil content, fatty acid and tocopherol profiles. Gas liquid chromotography and high performance liquid chromotography were used for fatty acid and tocopherol analysis, respectively. The oil contents of rape and canola seeds varied between 30.6% and 48.3% of the dry weight (p

This study aims to examine variations in β-sitosterol and α-, β-, γ-, and δ-tocopherol composition and content in sorghum grains with different genotypes and cultivation areas (Wonju and Miryang in Korea). β-Sitosterol content was found to be higher in Wonju sorghum; however, total tocopherol content was found to be higher in Miryang sorghum. Moreover, the β-sitosterol content did not correlate with physical characteristics, including 100-seed weight and color values (L, a, and b), but it was negatively correlated with total tocopherol content. β-Tocopherol was a major tocopherol in sorghum, constituting approximately 40%–46% of the total tocopherol content, and it was highly correlated with the total tocopherol content. Furthermore, the α-tocopherol content also increased with increasing γ-tocopherol content. Among the 4 tocopherols, only δ-tocopherol content correlated with physical characteristics of sorghum grain. This study deepened our knowledge of the variations in β-sitosterol and α-, β-, γ-, and δ-tocopherol content in sorghum with respect to genotype and cultivation location. In addition, this study demonstrated a correlation between some physical characteristics of sorghum and β-sitosterol/tocopherol content, and this information can be useful for breeding programs that develop or breed sorghum varieties or manufacture sorghum-based foods containing high amounts of β-sitosterol and tocopherols.

Understanding the mechanism of interaction between the oil palm and its key pathogen, Ganoderma spp. is crucial as the disease caused by this fungal pathogen leads to a major loss of revenue in leading palm oil producing countries in Southeast Asia. Here in this study, we assess the morphological and biochemical changes in Ganoderma disease infected oil palm seedling roots in both resistant and susceptible progenies. Rubber woodblocks fully colonized by G. boninense were applied as a source of inoculum to artificially infect the roots of resistant and susceptible oil palm progenies. Gas chromatography-mass spectrometry was used to measure an array of plant metabolites in 100 resistant and susceptible oil palm seedling roots treated with pathogenic Ganoderma boninense fungus. Statistical effects, univariate and multivariate analyses were used to identify key-Ganoderma disease associated metabolic agitations in both resistant and susceptible oil palm root tissues. Ganoderma disease related defense shifts were characterized based on (i) increased antifungal activity in crude extracts, (ii) increased lipid levels, beta- and gamma-sitosterol particularly in the resistant progeny, (iii) detection of heterocyclic aromatic organic compounds, benzo [h] quinoline, pyridine, pyrimidine (iv) elevation in antioxidants, alpha- and beta-tocopherol (iv) degraded cortical cell wall layers, possibly resulting from fungal hydrolytic enzyme activity needed for initial penetration. The present study suggested that plant metabolites mainly lipids and heterocyclic aromatic organic metabolites could be potentially involved in early oil palm defense mechanism against G. boninense infection, which may also highlight biomarkers for disease detection, treatment, development of resistant variety and monitoring.

The wild mushroom Leucopaxillus candidus (Bres.) Singer was studied for the first time to obtain information about its chemical composition, nutritional value and bioactivity. Free sugars, fatty acids, tocopherols, organic and phenolic acids were analysed by chromatographic techniques coupled to different detectors. L. candidus methanolic extract was tested regarding antioxidant potential (reducing power, radical scavenging activity and lipid peroxidation inhibition). L. candidus was shown to be an interesting species in terms of nutritional value, with high content in proteins and carbohydrates, but low fat levels, with the prevalence of polyunsaturated fatty acids. Mannitol was the most abundant free sugar and β-tocopherol was the main tocopherol isoform. Other compounds detected were oxalic and fumaric acids, p-hydroxybenzoic and cinnamic acids. The methanolic extract revealed antioxidant activity and did not show hepatoxicity in porcine liver primary cells. The present study provides new information about L. candidus. The authors are grateful to Foundation for Science and Technology (FTC, Portugal) for financial support to CIMO (Pest-OE/AGR/UI0690/2014) and L. Barros (SFRH/BPD/107855/2015) grant.

Study design Cross-sectional cohort study of elderly people. Objective The relationships of osteophyte formation on plain lumbar radiographs with serum levels of antioxidants (carotenoids, vitamin A, vitamin E) and other factors were investigated to examine whether antioxidants are involved in lumbar spine degeneration. Summary of background data Antioxidants have inhibitory effects on the onset of many diseases. However, the association of lumbar osteophyte formation with antioxidant levels in the general population has not been investigated. Methods The subjects were 286 people (103 men and 183 women; mean age = 68 years) who underwent resident health screening. Osteophyte formation on lumbar lateral radiographs (Nathan classification), lumbar lordosis angles, sacral inclination angles, serum levels of antioxidants, triglyceride levels, body mass index, osteoporosis, back muscle strength, history of alcohol intake, and smoking history were studied in these subjects. Results Lumbar osteophyte formation was detected in 48 subjects (17%). Osteophyte formation was significantly more common in elderly persons, men, and subjects with a history of alcohol intake; and had a significant correlation with sacral inclination angle. The levels of α-tocopherol, β-tocopherol, zeaxanthin/lutein, cryptoxanthin, lycopene, α-carotene, and β-carotene were significantly lower in subjects with osteophytes. Logistic regression analysis adjusted for all factors showed that a higher age (odds ratio [OR] = 1.1, 95% confidence interval [CI] = 1.02-1.16; P = 0.02) and a low β-carotene level (OR = 6.7, 95% CI = 1.39-32.6; P = 0.02) were risk factors for osteophyte formation. Conclusion The serum levels of carotenoids and vitamin E were significantly lower in subjects with lumbar osteophyte formation, and a low β-carotene level was the strongest risk factor for lumbar osteophytes. This is the first evidence of an association between carotenoids and lumbar osteophyte formation. This finding suggests that appropriate dietary intake of antioxidants is important for inhibition of lumbar spine degeneration in a rapidly aging society.

The contents of antioxidant compounds were examined in four commercial samples of caper, which is one of the most commonly found aromatics in the Mediterranean kitchen. Analyses were performed by using the colorimetric assay (total phenolic compounds and vitamin C) and high-performance liquid chromatography (rutin, carotenoids and tocopherols). Moreover, vitamin A activity (as retinol equivalents) was calculated. Phenolic compound contents ranged from 1151.6 ± 19.8 to 2243.96 ± 48.2 mg/100 g FW, while rutin contents ranged from 150.62 ± 5.18 to 732.61 ± 10.49 mg/100 g FW. Total tocopherol content was from 700.23 ± 10.49 to 2555.41 ± 71.12 µg/100 FW, with α-tocopherol as the predominant isomer in all samples. β-carotene ranged between 84.8 ± 9.5 and 805.71 ± 17.73 µg/100 g FW. Capers also contained an appreciable amount of vitamin C. These results bring attention to the antioxidant vitamin value and nutritional importance of commercial caper. PRACTICAL APPLICATIONS Results show that caper contain significant amounts of antioxidants (total phenolic compounds, rutin, tocopherols, carotenoids; and appreciable levels of vitamin C) as bioactive compounds. Irrespective of the variation between countries, commercial caper contained important contents of these compounds, thus showing caper has a great interest for its nutritional value. The combined contents of these antioxidants in commercial capers encourage consumers to increase their intake. Also, these results should be useful for researchers to explore and develop further this plant and its storage conditions for human consumption and medicinal uses.

Summary Commercially grown US Runner peanuts from 10 cultivars comprising 151 samples over two recent crop years contained 10.54 ± 1.50 mg α-tocopherol (T)/100 g kernel, 0.31 ± 0.12 β-T, 10.93 ± 2.04 γ-T and 0.76 ± 0.31 δ-T. Box plots revealed segregations in tocopherol levels for normal, mid and high oleic cultivars as well as production years among the cultivars. Correlation coefficients indicated positive relationships between β- and γ-T (r = 0.436, P

Summary Recently, hybrid hazelnuts have emerged as a potential oilseed crop in Nebraska for food and value-added industrial applications. As with all hazelnuts, Nebraska hybrid hazelnuts were characterised by the high oil content with the average oil content of 54.3%. Oleic acid was the predominant fatty acid. Oleic acid and linoleic acid accounted for more than 90% of the total fatty acid composition, whereas small quantities of palmitoleic and linolenic acids were found. Four major tocopherols (α-, β-, γ- and δ-tocopherols) were identified with α-tocopherol as the most dominant isomer. The average total tocopherol content was 235.4 mg kg−1 oil with α-tocopherol constituting approximately 97.5% of the total tocopherols. β-sitosterol was the most abundant sterol of the three identified sterols representing, on average, 93.1% of total sterols, followed by campesterol and stigmasterol. The oil oxidative stability was affected by the presence of high levels of natural antioxidants and monounsaturated fatty acids (MUFA). Genotype 16–177 was superior to the other genotypes, when combining high levels of MUFA, tocopherols and phytosterols, and high oxidative stability.

Spray irrigation of crop plants can represent a risk if the water is contaminated with cyanotoxins. These secondary metabolites produced by many cyanobacteria can have adverse effects on organisms, among others the induction of excess oxygen radicals, so-called oxidative stress. Thereby tocopherol as a lipid antioxidant is essential to maintain membrane integrity. In this study the effects of the cyanotoxin microcystin-LR (MC-LR), and a Microcystis crude extract ( Mic -CE) containing MC-LR on tocopherol content and gene expression of Homogentisate phytyltransferase (HPT), involved in tocopherol synthesis, were investigated in seedlings of the crop plant Medicago sativa . Exposures to environmental relevant concentrations showed that Mic -CE affects the tocopherols at a lower concentration than the pure toxin. Changes during a 3-day exposure using 0.5 μg L −1 MC-LR and Mic -CE revealed strong increases of α- and β-tocopherol content, whereas the influence on β-tocopherol was far stronger than on α-tocopherol. The HPT mRNA was elevated after 24 and 72 h exposure to MC-LR. These results show that also low concentrations of cyanobacterial toxins in the water have strong influence on tocopherol in M. sativa seedlings and therefore represent a stress for the plants.

In this work the effect of genetic and agronomic factors on virgin olive oil tocopherol content and composition has been studied. For genetic effect, olive oil from thirty olive cultivars has been analyzed; for agronomic factor evaluation, three olive cultivars have been monitored during fruit ripening for three consecutive crop years. Total tocopherol content has ranged between 84 and 463 mg/kg, α-tocopherol represented more than 95%, β-tocopherol was found at very low concentrations whereas γ-tocopherol varied from 1 to 29 mg/kg. Tocopherols in virgin olive oil have a significant genetic component. Variability by crop year was due to the rainfall levels, and oils from the drier crop year (1998/99) showed the highest tocopherol content. However, this effect was cultivar-dependent, with ‘Hojiblanca’ cultivar the most affected. In general, tocopherols decreased during the ripening process, and although γ-tocopherol showed an increase for the last harvesting dates, this trend was related to the chlorophyll losses in the oil.

Soybeans are an important source of tocopherols, which have health-beneficial properties. Previous studies have demonstrated that environmental factors may affect soybean tocopherol concentrations; the impact of specific crop management strategies, however, remains poorly understood. Experiments were conducted for 2 years at three sites in Quebec to determine the impact on soybean tocopherol concentrations of seeding rate, row spacing, seeding date, cultivar, and P and K fertilization. Total and alpha-, gamma-, and delta-tocopherol concentrations were determined by high-performance liquid chromatography. Overall, alpha-tocopherol was the most responsive to the factors evaluated; the response of other tocopherols was often lower or inconsistent across environments. The seeding rate affected alpha-tocopherol concentrations in three out of five environments; seeding at a rate of 40 seeds m(-2) resulted in 4% higher concentrations than seeding at a higher rate. Wide row spacing (more than 36 cm) resulted in two out of five environments in 6% higher alpha-tocopherol concentrations as compared to narrower row spacing. The seeding date had a greater impact; mid- to late-May seeding across four environments resulted in 45% greater alpha-tocopherol concentrations than seeding at later dates. Phosphorus and K fertilization had a negligible impact on tocopherol concentrations. Across experiments, large differences were observed between environments; plants grown in northern environments consistently had lower concentrations of alpha- and gamma-tocopherols but higher concentrations of delta-tocopherol. Differences between cultivars were also consistent, ranging between 10 and 30%, depending on the tocopherol. Results demonstrate that soybean tocopherol concentrations are affected by crop management and thus suggest that specific recommended agronomic practices may need to be established for the production of soybeans for the functional food market.

Annona squamosa and Catunaregam nilotica seeds and oils were characterized for their approximate analysis and physico-chemical properties. The oil and protein contents were 26.8, 17.5 and 40.0, 22.2%, in A. squamosa and C. nilotica seeds, respectively. The oils were extracted using cold extraction (CE) and Soxhlet extraction (SE) methods. Fatty acids and tocopherols were determined by GC–MS and HPLC, respectively. Generally the physico-chemical properties and fatty acids were not significantly (P ≤ 0.05) affected by the extraction methods. The major fatty acids of A. squamosa oil extracted by CE and SE were oleic 49.2 and 50.5%, linoleic 22.3 and 22.7%, palmitic 15.6 and 15.2%, and stearic 10.6 and 9.3%, respectively. While the major fatty acids in C. nilotica oil extracted by CE and SE were oleic 10.5, and 10.4%, linoleic 63.1 and 63.4%, palmitic 9.7 and 9.8% and stearic 5.1 and 5.4%, respectively. The tocopherol content of CE and SE extracted oils from A. squamosa amounted to 16.6 and 15.5 and from C. nilotica amounted to 110.5 and 107.7 mg/100 g oil, respectively, with delta-tocopherol as the predominant tocopherol in A. squamosa oil, and beta-tocopherol in C. nilotica oil. The total amount of amino acids was found to be 7.266 and 14.202 g/100 g protein, in seeds of A. squamosa and C. nilotica, respectively.

Black currant is known as a fruit with a very strong in vitro antioxidative capacity, but its in vivo antioxidant efficacy has not yet been characterized. The aim of the experiment was to determine the potency of black currant juice in comparison to vitamin E, for decreasing oxidative stress. Oxidative stress was induced by high intake of polyunsaturated fatty acids (PUFAs) in pigs as a model for humans. Twenty-four growing pigs were divided into four groups. All groups received isocaloric daily rations composed of an equal amount of basal diet that was supplemented with starch (CONT), linseed oil (OIL), linseed oil and black currant juice (OIL+BCJ), or linseed oil and vitamin E (OIL+VIT E). The experiment confirmed that the high proportion of PUFAs in the OIL group increased oxidative stress. In comparison with the OIL group, vitamin E supplementation significantly lowered plasma malondiadehyde (MDA) and the 24-hour urine MDA excretion rate, and reduced the degree of DNA damage in leukocytes to the level of the CONT group. The black currant juice intake failed to significantly decrease plasma MDA and 24-hour urine MDA excretion rate, but did reduce the degree of DNA damage in leukocytes to the level of the CONT group, as well as increase plasma β+γ-tocopherol concentrations. Although black currant juice did not reduce the formation of MDA, it efficiently prevented DNA damage induced by the high intake of PUFAs. It could be concluded that under these experimental conditions vitamin E was more efficient as an antioxidant that black currant juice.

Tocopherols (vitamin E) comprise a class of lipid-soluble antioxidants synthesized only in plants, algae, and some cyanobacteria. The majority of tocopherols in photosynthetic cells is in the α form, which has the highest vitamin E activity in humans, whereas the β, γ, and δ forms normally account for a small percentage of total tocopherols. The antioxidant activities of these forms of tocopherol differ depending on the experimental system, and their relative activities in vivo are unclear. In a screen for suppressors of the xanthophyll-deficient npq1 lor1 double mutant of Chlamydomonas reinhardtii , we isolated a vte3 mutant lacking α-tocopherol but instead accumulating β-tocopherol. The vte3 mutant contains a mutation in the homolog of a 2-methyl-6-phytyl-1,4-benzoquinone methyltransferase gene found in plants. The vte3 npq1 lor1 triple mutant with β-tocopherol survived better under photooxidative stress than did the npq1 lor1 mutant, but the vte3 mutant on its own did not have an obvious phenotype. Following transfer from low light to high light, the triple mutant showed a higher efficiency of photosystem II, a higher level of cell viability, and a lower level of lipid peroxide, a marker for oxidative stress, than did the npq1 lor1 mutant. After high-light transfer, the level of the photosystem II reaction center protein, D1, was also higher in the vte3 npq1 lor1 mutant, but the rate of D1 photodamage was not significantly different from that of the npq1 lor1 mutant. Taken together, these results suggest that the replacement of α-tocopherol by β-tocopherol in a xanthophyll-deficient strain of Chlamydomonas reinhardtii contributes to better survival under conditions of photooxidative stress.

OBJECTIVE The aim was to investigate the association between periodontal health and the serum levels of various antioxidants including carotenoids, retinol and vitamin E in a homogenous group of Western European men. MATERIALS AND METHODS A representative sample of 1258 men aged 60-70 years, drawn from the population of Northern Ireland, was examined between 2001 and 2003. Each participant had six or more teeth, completed a questionnaire and underwent a clinical periodontal examination. Serum lipid-soluble antioxidant levels were measured by high-performance liquid chromatography with diode array detection. Multivariable analysis was carried out using logistic regression with adjustment for possible confounders. Models were constructed using two measures of periodontal status (low- and high-threshold periodontitis) as dependent variables and the fifths of each antioxidant as a predictor variable. RESULTS The levels of alpha- and beta-carotene, beta-cryptoxanthin and zeaxanthin were highly significantly lower in the men with low-threshold periodontitis (p

The present paper reports the development and validation of an analytical micro-method for tocopherols quantification in espresso coffee by normal-phase HPLC with fluorescence detection. The proposed method consists in a liquid–liquid extraction with n -hexane:ethyl acetate, followed by a clean-up with dimethylformamide to eliminate co-eluting interferences. The method showed good intra- and inter-day precisions (coefficient of variation r > 0.999) for standards subjected to the entire procedure. Only α- and β-tocopherols were identified in the brews. The detection and quantification limits were 0.5 and 1.4 ng/ml, for α-tocopherol, and 0.4 and 1.1 ng/ml, for β-tocopherol, respectively. A mean total tocopherol content (α + β) of 3.5 ± 0.9 μg in commercial espresso coffee blends (30 ml) was detected. The proposed method requires low solvent consumption and proved to be sensitive, precise and accurate.

Reduced levels of circulating sex hormone-binding globulin (SHBG) are implicated in the etiology of sex steroid-related pathologies and the metabolic syndrome. Dietary correlates of serum SHBG remain unclear and were studied in a convenient cross-sectional sample of healthy 30- to 40-y-old women (n = 255). By univariate analyses, serum SHBG correlated negatively with several indices of the metabolic syndrome, such as BMI, waist circumference, hip circumference (r = −0.36 to −0.44; P < 0.0001), fasting serum insulin (r = −0.41; P < 0.0001), serum triglycerides (r = −0.27; P < 0.0001), serum glucose (r = −0.23; P < 0.001), and plasma testosterone (r = −0.19; P = 0.002). Serum SHBG correlated positively with serum HDL-cholesterol (r = 0.33; P < 0.0001), plasma progesterone (r = 0.17; P = 0.007), and dietary intake of β-tocopherol (r = 0.17; P = 0.006), and negatively with that of fructose (r = −0.13; P = 0.04). Principal component analysis (PCA) extracted 12 nutrient factors with eigenvalues > 1.0 from 54 nutrients and vitamins in food records. Multivariate regression analyses showed that the PCA-extracted nutrient factor most heavily loaded with β-tocopherol and linoleic acid (P = 0.03) was an independent positive predictor of serum SHBG. When individual nutrients were the predictor variables, β-tocopherol (P = 0.002), but not other tocopherols or fatty acids (including linoleic acid), was an independent positive predictor of serum SHBG. Circulating insulin (P = 0.02) and waist circumference (P = 0.002), but not serum lipids, were negative independent predictors of SHBG in all regression models. Additional studies are needed in women of other age groups and men to determine whether consumption of foods rich in β-tocopherol and/or linoleic acid may increase serum SHBG concentrations and may thereby decrease the risk for metabolic syndrome and reproductive organ cancer.

The tocopherol profiles of arabica and robusta coffee beans, both green and roasted, were ascertained. A solid-liquid micro-extraction method was used, and the quantification performed by normal-phase HPLC/diode-array/fluorescence detection. Regarding green arabicas, the mean contents were 2.7 ± 0.4 mg/100 g, for α-tocopherol, and 8.0 ± 0.9 mg/100 g, for β-tocopherol. For green robustas, mean values of 1.7 ± 0.3 and 2.1 ± 0.3 mg/100 g were found for α- and β-tocopherol, respectively. Generally, more than 90% of tocopherols remained after the roasting procedure, except for β-tocopherol in robustas, whose mean degradation was approximately 25% when expressed as dry weight. No γ-tocopherol was detected in any sample. The results show that tocopherol profile could be useful in the discrimination of arabica and robusta coffees (either green or roasted).

In order to demonstrate whether the known biological effects of Aloe vera (L.) Burm. fil. could correlate with the antioxidant activity of the plant, the antioxidant activity of the aqueous leaf extract was investigated. The present study demonstrated that the aqueous extract from A. vera leaves contained naturally occuring antioxidant components, including total phenols, flavonoids, ascorbic acid, beta-carotene and alpha-tocopherol. The extract exhibited inhibitory capacity against Fe(3+)/ascorbic acid induced phosphatidylcholine liposome oxidation, scavenged stable DPPH(*), ABTS(*+) and superoxide anion radicals, and acted as reductant. In contrast, the leaf inner gel did not show any antioxidant activity. It was concluded that the known beneficial effects of Aloe vera could be attributed to its antioxidant activity and could be related to the presence of phenolic compounds and antioxidant vitamins.

The effect of irradiation (0–20 kGy) on hemp and sunflower seeds was assessed, with specific reference to the oxidatively labile lipid component (unsaturated fatty acids and tocochromanols). Total protein, lipid, and solids content of the seeds did not vary with irradiation dose. Lipid hydroperoxide concentration increased significantly in the sunflower seeds (48 mmol kg−1 lipid) and a significant increase in volatile secondary oxidation products was measured in both seeds (e.g. hexanal, heptanal, 1-penten-3-ol) with increasing irradiation dose. Irradiation at 5 kGy sterilised the seeds of all microbial contamination and irradiation doses of 20 kGy prevented germination. A loss of the antioxidant tocopherol was shown with increasing irradiation doses, although this was selective for specific tocopherol isoforms (α-tocopherol, β-tocopherol and γ-tocopherol).

The tocopherols (alpha, beta-, gamma-, and delta-tocopherol) and resveratrol are phytochemicals with alleged beneficial effects against atherosclerosis, vascular diseases and different cancers. They both can act as antioxidants, but they also modulate signal transduction and gene expression by non-antioxidant mechanisms. Here we wanted to determine whether the combined treatment of mast cells with the two compounds inhibits cell proliferation more efficiently when compared to individual treatments. Both compounds inhibit HMC-1 mastocytoma cell proliferation and reduce the activity of Protein Kinase B (PKB/Akt) by inhibiting its Ser473-phosphorylation. The combination of 50 microM delta-tocopherol and 50 microM resveratrol inhibits proliferation of HMC-1 cells more efficiently when compared to single treatments. In line with this, PKB Ser473-phosphorylation is inhibited best by delta-tocopherol and resveratrol combinatory treatment. Resveratrol acts more efficiently as an inhibitor of PKB phosphorylation than alpha-, beta-, gamma-tocopherols, whereas delta-tocopherol shows a stronger inhibition possibly as a result of its apoptotic secondary effects. Our data suggest that delta-tocopherol and resveratrol can act additively in reducing cell proliferation and PKB phosphorylation. The combination of phytochemicals with relatively broad specificity on enzymes involved in signal transduction and gene expression may increase their activity in disease prevention by modulating several different molecular targets.

Objective Insulin resistance is common in individuals with chronic kidney disease (CKD) and may be partly explained by modifiable risk factors. In the general population, vitamin E supplementation has been suggested to improve both insulin sensitivity and secretion. We here explore the potential role of vitamin E as a modifiable risk factor for insulin resistance among individuals with CKD. Design Observational study. Setting A total of 273 nondiabetic men aged 70 to 71 years with CKD defined as either cystatin C estimated glomerular filtration rate 2 or urinary albumin excretion rate ≥ 20 mg/minute from the third examination cycle of Uppsala Longitudinal Study of Adult Men. Subjects A total of 273 nondiabetic men aged 70 to 71 years with CKD defined as either cystatin C estimated glomerular filtration rate 2 or urinary albumin excretion rate ≥ 20 μg/minute. Methods Serum α-, β-, and γ-tocopherol concentrations were measured by high-performance liquid chromatography and expressed as μmol/total serum cholesterol and triglycerides (in mmol). Dietary vitamin E intake was estimated from 7-day food records. Main Outcome Measure Insulin sensitivity index (M/I ratio) was measured by hyperinsulinemic-euglycemic glucose clamps. Univariate and multivariate regression models were fitted to assess the association between M/I and circulating concentrations of tocopherols. Results The mean serum concentration of α-, β-, and γ- was 37.4 ± 6.58, 0.89 ± 0.23, and 4.32 ± 1.69 μmol/mmol, respectively. Median dietary vitamin E intake was 6.14 (interquartile range, 5.48-6.82) mg/day. In crude and fully-adjusted multivariate regression analyses, serum α-tocopherol levels were directly and strongly associated with M/I (standard β = 0.17, P = .003). No such association was observed for dietary vitamin E, serum β-, and γ-tocopherol concentrations. Conclusions Serum α-tocopherol concentration associates with insulin sensitivity in nondiabetic older men with CKD.

Although much study has been done assessing activity of antioxidants at ambient and accelerated storage temperatures, the results cannot correctly depict their performance under frying conditions. Due to the stringent conditions imposed, most conventional antioxidative compounds failed under frying conditions, suggesting the need for a continuous modification to improve their effectiveness. Although syntheses and performance evaluation of over a hundred (semi)synthetic antioxidants have been reported in literature, only a small fraction have been specifically designed and/or evaluated under frying conditions. Here, the performance under frying conditions of major natural and synthetic antioxidants is reviewed. The recent trend in the designing of antioxidants for frying applications is also reviewed with the view of stimulating further study in this direction.

A very well-known and appreciated mushroom, Agrocybe aegerita (Brig.) Sing, was the subject of chemical profiling, antioxidant assays and sensory evaluation test in cream cheese. Methanolic extract obtained from a wild sample of A. aegerita fruiting body was fully chemically identified. Sample was found to be rich in carbohydrates (84.51 g/100 g dw), ash and proteins (6.69 g/100 g dw and 6.68 g/100 g dw, respectively). Trehalose was the main free sugar while malic acid was the most abundant organic acid. Four isoforms of tocopherols were identified; gamma- tocopherol was the dominant isoform with 86.08 mu g/100 g dw, followed by beta- tocopherol, delta-tocopherol and alpha-tocopherol (8.80 mu g/100 g dw, 3.40 mu g/100 g dw and 2.10 mu g/100 g dw, respectively). Polyunsaturated fatty acids were predominant, with linoleic acid as the most prominent one (78.40 \%). Methanolic extract of chestnut mushroom exhibited high antioxidant activity. Sensory evaluation test included grading by panelists and comparing the overall acceptability of cream cheese alone and enriched cream cheese with dry powder of A. aegerita. General conclusion of the participants was that the newly developed product was more likeable in comparison to cream cheese alone. Due to the health-beneficial effects of antioxidants and wealth of chemically identified nutrients, A. aegerita is a promising starting material for incorporation on larger scale products. Ministry of Education, Science and Technological Development of Serbia {[}173032]; Foundation for Science and Technology (FCT, Portugal) {[}SFRH/BD/76019/2011]

SUMMARY Two different sunflower lines with increased beta-tocopherol concentration in the seeds, LG-15 and T589, have been developed. The objective of the present research was to conduct a comparative genetic study of the increased beta-tocopherol concentration in both lines. Plants of LG-15 were reciprocally crossed with plants of T589 in 2003. The F1, F2, BC to LG-15 and BC to T589 seed generations were produced in the same environment in 2004 and analyzed for tocopherol profile. The results indicated a strong environmental effect on the increased levels of beta-tocopherol concentration in LG-15 and T589, which averaged 30.5% and 25.8%, respectively, in 2003 and 43.2% and 54.0%, respectively, in 2004. The comparison of individual plant means and standard errors of individual plant means for the F2 and BC generations with those in the non-segregating parental and F1 generations indicated no transgressive segregation for beta-tocopherol concentration in F2 or BC seeds. These results suggested that increased beta-tocopherol concentration in both lines is the result of genetic alterations at the same locus.

During a study of the effect of vitamin E in activated mouse macrophages, we observed a reduction in the viability of cells treated with various forms of vitamin E. We show in this report that some tocopherols (both gamma- and delta-tocopherol) are cytotoxic to some but not all cell types. Mouse macrophages were especially sensitive (40 micromol/L), whereas human hepatocytes and bovine endothelial cells were almost completely refractory (90 micromol/L). The fully methylated tocopherol, alpha-tocopherol (alpha-Toc), was not cytotoxic in any cell type tested. The cytotoxicity observed with delta-tocopherol (delta-Toc) was associated with 2 markers of apoptosis. Vitamer-specific cytotoxicity was not due to differences in cellular uptake/accumulation because both alpha-Toc and delta-Toc accumulated equally in any cell type tested. In contrast, the cell-specific cytotoxicity was related in part to uptake/accumulation of the tocopherols. Macrophages accumulated nearly 5 times more tocopherol compared with hepatocytes cultured under similar conditions. To address the hypothesis that uptake accounted for the cell-specific sensitivity, we developed a macrophage "subtype" that was markedly resistant (150 micromol/L) to delta-Toc. Under many different cell culture conditions (including human serum) uptake/accumulation of tocopherols was reduced in this subtype by approximately 50%. Further selection and evaluation of this phenotype, however, demonstrated no cytotoxicity even when cellular levels were elevated. Our results show that undermethylated tocopherols are cytotoxic to macrophages and that there are independent and selectable processes that determine cellular tocopherol uptake/accumulation and delta-Toc cytotoxicity.

The objective of the study was to examine whether serum concentrations of retinol (vitamin A) and alpha-, beta-, and gamma-tocopherols (vitamin E) are affected by underweight and weight gain. The analysis was carried out in underweight (n = 42, of whom 24 had chronic obstructive pulmonary disease) and normal-weight (n = 29, of whom 16 had chronic obstructive pulmonary disease) candidates for lung transplantation before and after dietary intervention for weight gain. In all the patients, serum concentrations of retinol at baseline and changes in retinol were positively associated with body mass index (unstandardized regression coefficient, b = 0.03; p = 0.05) and an increase in weight (b = 0.09, p = 0.02) after dietary intervention, respectively. At baseline, serum retinol concentrations were positively correlated with forced vital capacity (b = 0.24, p < 0.05) and forced expiratory volume in one second (b = 0.17, p < 0.05). In patients with chronic obstructive pulmonary disease (COPD), tocopherols were higher in the underweight patients than in the normal-weight ones, while it was an opposite tendency in patients with other lung diseases. Only in patients with lung diseases other than COPD was there found a positive association between tocopherols and lung gas diffusion. In patients with other diagnoses compared with patients with COPD, a positive change in serum tocopherol status after weight gain was suggested.

Tocopherols, synthesized by photosynthetic organisms, are micronutrients with antioxidant properties that play important roles in animal and human nutrition. Because of these health benefits, there is considerable interest in identifying the genes involved in tocopherol biosynthesis to allow transgenic alteration of both tocopherol levels and composition in agricultural crops. Tocopherols are generated from the condensation of phytyldiphosphate and homogentisic acid (HGA), followed by cyclization and methylation reactions. Homogentisate phytyltransferase (HPT) performs the first committed step in this pathway, the phytylation of HGA. In this study, bioinformatics techniques were used to identify candidate genes,slr1736 and HPT1, that encode HPT fromSynechocystis sp. PCC 6803 and Arabidopsis, respectively. These two genes encode putative membrane-bound proteins, and contain amino acid residues highly conserved with other prenyltransferases of the aromatic type. A Synechocystissp. PCC 6803 slr1736 null mutant obtained by insertional inactivation did not accumulate tocopherols, and was rescued by the Arabidopsis HPT1 ortholog. The membrane fraction of wild-type Synechocystis sp. PCC 6803 was capable of catalyzing the phytylation of HGA, whereas the membrane fraction from the slr1736 null mutant was not. The microsomal membrane fraction of baculovirus-infected insect cells expressing the Synechocystis sp. PCC 6803slr1736 were also able to perform the phytylation reaction, verifying HPT activity of the protein encoded by this gene. In addition, evidence that antisense expression of HPT1in Arabidopsis resulted in reduced seed tocopherol levels, whereas seed-specific sense expression resulted in increased seed tocopherol levels, is presented.

Flaxseed (Linum usitatissimum L.) oil was obtained via subcritical n-propane fluid extraction (SubFE) under different temperatures and pressures with an average yield of 28% and its composition, purity and oxidative stability were compared to oils obtained via conventional solvent extraction methods (SEMs). When the oxidative stability was measured by differential scanning calorimetry, the oil was found to be up to 5 times more resistant to lipid oxidation as compared to the SEM oils. Direct infusion electrospray ionization mass spectrometry (ESI-MS) analysis showed characteristic and similar TAG profiles for SubFE and SEMs oils but higher purity for the SubFE oil. The flaxseed oil content of β-tocopherol, campesterol, stigmasterol and sitosterol were quantified via GC–MS. SubFE showed to be a promising alternative to conventional SEM since SubFE provides an oil with higher purity and higher oxidation stability and with comparable levels of biologically active components.

The present study examined the contents of tocopherols and tocotrienols and their distribution in 58 different varieties of whole rice cultivated in Malaysia. The analytical method used was saponification of samples followed by dispersive liquid-liquid microextraction and reverse phase high-performance liquid chromatography.The total vitamin E contents of different varieties of whole rice ranged between 19.36 and 63.29 mg kg⁻¹. Contents of vitamin E isomers varied among rice varieties both within and between grain color groups. Black-pigmented rice showed significantly higher mean contents of α-tocopherol, β-tocopherol and α-tocotrienol than non-pigmented rice and red-pigmented rice. Red-pigmented rice had significantly lower mean contents of γ-tocotrienol and total vitamin E than non-pigmented rice. The mean contents of δ-tocotrienol and total vitamin E in non-pigmented rice, however, were similar to those in black-pigmented rice. γ-Tocotrienol was the predominant form of vitamin E isomer in all analyzed varieties. The Pearson correlations among vitamin E isomers and total vitamin E content of whole rice were also studied.This study provides information on vitamin E content of different rice varieties that would be beneficial for decision making in genetic breeding of bioactive compound-rich rice varieties.

Natural vitamin E is composed of eight different vitamers (alpha-, beta-, gamma- and delta-tocopherols and alpha-, beta-, gamma- and delta-tocotrienols). As these eight vitamers have different antioxidant and biological activities, it is necessary to have quantitative data on each substance separately. The aim of this study was to find universal HPLC columns for the separation of all eight components and to test if a few columns of the same material (different batches) will give reproducible results. Normal-phase HPLC separations of vitamin E compounds in a prepared mixture (containing oat extracts, palm oil and tocopherol standards) were tried on six silica, three amino and one diol columns. As shown by calculations of retention factors (k), separation factors (alpha), numbers of theoretical plates (N) and resolutions (Rs), the best separations were obtained on three silica columns and two amino columns using 4 or 5% dioxane in hexane as the mobile phase as well as on a diol column using 4% tert.-butyl methyl ether in hexane as the mobile phase.

We analysed the triacylglycerol, tocopherol and sterol composition of hazelnut oil, olive oil and their mixtures (90% olive oil with 10% hazelnut oil, 70% olive with 30% hazelnut oil and 50% olive oil with 50% hazelnut oil). The main triacylglycerols were 1,2,3-trioleylglycerol, 2,3-dioleyl-1-palmitoylglycerol, 2,3-dioleyl-1-linoleylglycerol and 2,3-dioleyl-1-stearoylglycerol. Non-saponfiable compounds (tocopherols and sterols) were derivatised as O-trimethylsilyl ethers. Alpha-tocopherol was the main vitamin E isomer in all samples; however, small amounts of beta-tocopherol and gamma-tocopherol were also found. Beta-sitosterol and delta5-avenasterol were the principal sterols in all samples; campesterol and stigmasterol were minor sterol compounds in all samples. Obtusifoliol, which was a major sterol in olive oil and oil mixtures, was not found in hazelnut oil. The discriminant analysis showed that hazelnut oil, olive oil and oil mixtures were clearly separated according to their triacylglycerol composition.

This study addresses issues regarding chemical and bioactive properties of nine wild edible mushrooms from native Nothofagus forest from Patagonia, Argentina. Macronutrients, sugars, fatty acids, tocopherols, organic acids, phenolic compounds and antioxidant properties were determined. Protein was found in high levels and varied between 3.35 g/100 g dw in Cyttaria hariotii and 22.29 g/100 g dw in Lepista nuda. All of them presented mannitol and trehalose as main sugars. Mannitol was significantly higher in Ramaria patagonica, although absent in Fistulina endoxantha, whereas trehalose predominated in Aleurodiscus vitellinus, Hydropus dusenii, Cortinarius magellanicus, C. hariotii, Grifola gargal and L. nuda, ranging from 1.15 to 10.26 g/100 g dw; it was absent in R. patagonica. The major fatty acid found was linoleic acid, followed by oleic acid and palmitic acid. All species presented oxalic and fumaric acids, while some also had malic, quinic and citric acids. Tocopherols composition was variable. Cortinarius magellanicus presented significantly higher contents of both α-tocopherol and β-tocopherol. R. patagonica presented the best results in all the antioxidant activity assays (EC50 values ≤ 1 mg/mL) and the highest content of phenolic compounds presenting gallic, p-hydroxybenzoic, p-coumaric and cinnamic acids. This study constitutes the first report on chemical composition and nutritional value of most of these edible mushroom species. Furthermore, it provides important information necessary to characterize and define the use of these species as gastronomic delicacies, functional foods and sources of bioactive compounds. info:eu-repo/semantics/publishedVersion

Vitamin E is thought to be involved in many essential processes in plants, but no functional proof has been reported. To study vitamin E deficiency in plants, a high-throughput biochemical screen for vitamin E quantification in Arabidopsis mutants has been developed, which has led to the identification of VTE1-encoding tocopherol cyclase. Interestingly, the corresponding maize mutation, sxd1, causes plasmodesmata malfunction, suggesting a link between tocopherol cyclase and plasmodesmata function.

Coriander is commonly used for medicinal purposes, food applications, cosmetics and perfumes. Herein, the production of antioxidants in vegetative parts (leaves and stems) of in vivo and in vitro grown samples was compared. In vitro samples were clone A- with notorious purple pigmentation in stems and leaves and clone B- green. Seeds were also studied as they are used to obtain in vivo and in vitro vegetative parts. Lipophilic (tocopherols, carotenoids and chlorophylls) and hydrophilic (sugars, ascorbic acid, phenolics, flavonols and anthocyanins) compounds were quantified. The antioxidant activity was evaluated by radical scavenging activity, reducing power and lipid peroxidation inhibition. The in vivo sample showed the highest antioxidant activity mainly due to its highest levels of hydrophilic compounds. Otherwise, in vitro samples, mainly clone A, gave the highest concentration in lipophilic compounds but a different profile when compared to the in vivo sample. Clones A and B revealed a lack of B-carotene, B- and δ-tocopherols, a decrease in alpha-tocopherol, and an increase in Y-tocopherol and clorophylls in comparison to the in vivo sample. In vitro culture might be useful to explore the plants potentialities for industrial applications, controlling environmental conditions to produce higher amounts of some bioactive products.

The presence of a series of tocopherols, designated as delta, gamma, beta and alpha, was determined in the seeds, pomace, bagasse and stalks of fifteen grape varieties grown in Turkey using a rapid HPLC method. The alpha form was the predominant tocopherol fraction, and varied from 4.692. mg/kg dry weight in seeds to 108.5. mg/kg dry weight in stalks. It was followed by the gamma and delta tocopherol forms found in all parts of clusters for all cultivars. The amount of beta tocopherol in stalks was considerably higher than in the other parts of the clusters, for all varieties. The total tocopherol content ranged from 6.048 to 25.86. mg/kg dry weight in seeds, from 19.85 to 89.02. mg/kg dry weight in pomace, from 29.18 to 184.7. mg/kg dry weight in bagasse and from 33.65 to 110.7. mg/kg dry weight in grape stalks. The results obtained from this study showed that all parts of the grape clusters are potentially rich sources of tocopherols with uses as antioxidants in food and industrial applications. © 2010 Elsevier Inc.

Temperature dependence of the autoxidation of perilla oil and tocopherol degradation was studied with corn oil as a reference. The oils were oxidized in the dark at 20, 40, 60, and 80 degrees C. Oil oxidation was determined by peroxide and conjugated dienoic acid values. Tocopherols in the oils were quantified by HPLC. The oxidation of both oils increased with oxidation time and temperature. Induction periods for oil autoxidation decreased with temperature, and were longer in corn oil than in perilla oil, indicating higher sensitivity of perilla oil to oxidation. However, time lag for tocopherol degradation was longer in perilla oil, indicating higher stability of tocopherols in perilla oil than in corn oil. Activation energies for oil autoxidation and tocopherol degradation were higher in perilla oil (23.9 to 24.2, 9.8 kcal/mol, respectively) than in corn oil (12.5 to 15.8, 8.8 kcal/mol, respectively) indicating higher temperature-dependence in perilla oil. Higher stability of tocopherols in perilla oil was highly related with polyphenols. The study suggests that more careful temperature control is required to decrease the autoxidation of perilla oil than that of corn oil, and polyphenols contributed to the oxidative stability of perilla oil by protecting tocopherols from degradation, especially at the early stage of oil autoxidation.

Vitamin E is a collective term for eight naturally occurring compounds, four tocopherols (alpha-, beta-, gamma-, and delta-) and four tocotrienols (alpha-, beta-, gamma-, and delta-). Although it is the major form of vitamin E in US diets, gamma-tocopherol receives little attention when compared to alpha-tocopherol, which is generally found in supplements and most studied for its effects on progression of cognitive impairment. Many clinical trials had been conducted with vitamin E and neurodegenerative disorders, with controversial results, including a recent study which disproves the benefit of vitamin E for Mild Cognitive Impairment and Alzheimer's Disease. This study examined the alpha-tocopherol supplement instead of gamma-tocopherol. Gamma-tocopherol has been found to be more effective in scavenging free radicals and nitrogen oxygen species that cause inflammation; both of these are components of neurodegenerative disorders. Secondly, the use of alpha-tocopherol supplements significantly reduces serum gamma-tocopherol, and this may have important biological effects. Therefore, any potential health benefits of alpha-tocopherol supplements may be offset by deleterious changes in the bioavailability of other forms of tocopherols and tocotrienols. This might account for the null effects of alpha tocopherol supplementation in Mild Cognitive Impairment and Alzheimer's Disease.