Cumulative oxidative damage from the unavoidable formation of reactive oxygen species (ROS) contributes to seed ageing. Low-molecular-weight (LMW) antioxidants, such as water-soluble glutathione (GSH) and lipid-soluble tocochromanols, can prevent ROS from causing damage, especially when antioxidant enzymes are inactive due to desiccation. However, loss of tocochromanols does not always accompany seed ageing, such as during accelerated ageing or controlled deterioration, despite the presence of oxygen and prevalent loss of GSH. To assess relationships between total germination (TG) and antioxidant changes under storage conditions with practical relevance, commercial seeds of Cucumis sativus, Daucus carota, Helianthus cucumerifolius, Latuca sativa, Lepidium sativum, Phaseolus vulgaris and Raphinus sativus of the same cultivar were obtained over multiple years and stored under ambient conditions (21.9 ± 2.1°C; 36.8 ± 6.6% relative humidity). Sigmoidal fitting of TG revealed time to when 50% of seeds had lost viability, which ranged from <5 years (D. carota) to >15 years (C. sativus). Cellular redox states were quantified via the half-cell reduction potential of LMW thiol/disulphide couples. These negatively correlated with TG (i.e. cell redox states were more oxidized in lots with lower TG), with an average R2 value of 0.62 for the most abundant thiol (GSH, or γ-glutamyl-cysteine in P. vulgaris). Concentrations of tocochromanols positively correlated with TG, with an average R2 value of 0.50 for the most abundant tocochromanol (γ or α in L. sativa and H. cucumerifolius). Therefore, during viability loss under ambient ageing conditions leading to the cytoplasm having a glassy state, the lipid domain in all species experienced oxidative damage.

We previously reported that dietary vitamin E deficiency increased anxiety-like behaviour in rats exposed to social isolation. Here, we performed a detailed investigation of this phenomenon and its underlying mechanism. First, we fed Wistar rats with a vitamin E-free diet for 3 d, 1 week or 2 weeks and found an increase in anxiety-like behaviour after 1 and 2 weeks of vitamin E deficiency based on behavioural indicators. Next, we examined the effect of a control diet (150 mg all-racemic α-tocopheryl acetate/kg) on anxiety-like behaviours in rats that received a 4-week vitamin E-free diet. We found that increased anxiety-like behaviour was reversed to control levels after refeeding vitamin E for 7 d but not for 1 or 3 d. Further, anxiety-like behaviour increased or decreased gradually based on the amount of vitamin E intake; however, it had a quicker progression than physical symptoms of vitamin E deficiency. Moreover, rats fed with excess vitamin E (500 mg all-racemic α-tocopherol/kg diet) showed less anxiety-like behaviour than control rats, indicating that vitamin E supplementation is effective for preventing anxiety increase under social isolation stress. Since plasma corticosterone levels were higher in vitamin E-deficient rats, we investigated the effect of adrenalectomy on anxiety-like behaviour and found that adrenal hormones played an essential role in the increased anxiety-like behaviour induced by vitamin E deficiency. In conclusion, increased anxiety-like behaviour is a symptom that emerges earlier than physical vitamin E deficiency and is caused by adrenal hormone-dependent mechanisms.

Soya bean is the main protein source in poultry feed but rising prices make an alternative protein source necessary. Insects, such as the black soldier fly (Hermetia illucens), may be an attractive solution for hens, although little information is available on their effect on egg quality. The present study aims to fill this gap by testing the effect of 100% replacement of soya bean with H. illucens larva meal in the diet of Lohmann Brown Classic laying hens for 21 weeks. At the end of the trial, the eggs were characterized for parameters such as weight, colour, proximate composition of albumen and yolk, and content of carotenoids, tocopherols and cholesterol. The fatty acid profile of yolks was also determined. Hens fed the insect-based diet produced eggs (HIM group) with a higher proportion of yolk than the group fed the soya bean-based diet (SBM group). HIM was associated with redder yolks (red index 5.63 v. 1.36) than SBM. HIM yolks were richer in γ-tocopherol (4.0 against 2.4 mg/kg), lutein (8.6 against 4.9 mg/kg), β-carotene (0.33 against 0.19 mg/kg) and total carotenoids (15 against 10.5 mg/kg) than SBM yolks. The fatty acid composition of HIM yolks was almost identical to that of SBM yolks. Finally, HIM yolks contained 11% less cholesterol than SBM yolks. These results suggest that H. illucens larva meal is a suitable total substitute for soya bean meal in the diet of Lohmann Brown Classic laying hens. A sustainable alternative to the plant protein source therefore seems feasible.

Vitamin E (tocols) is a key metabolite for efficient scavenging of lipid peroxy radicals that cause membrane breakdown during seed ageing. However, in rice, this hypothesis has been tested for very few lines only and without considering intraspecific variation in genomic structure. Here, we present a correlation study between tocols and seed longevity using a diverse rice panel. Seeds of 20 rice accessions held in the International Rice Genebank at the International Rice Research Institute, representing Aus, Basmati/Sadri, Indica, temperate Japonica and tropical Japonica variety groups, were used for tocols analysis (quantification of α-, β-, γ- and δ-tocopherol/tocotrienol by ultra-performance liquid chromatography) and storage experiments at 45°C and 10.9% seed moisture content. To examine the effects of DNA-haplotype on the phenotype, the 700 K high-density single-nucleotide polymorphism marker dataset was utilized. Both seed longevity (time for viability to fall to 50%; p50) and tocols content varied across variety groups related to the heterogeneity in the genetic architecture. Among eight types of tocol homologues, α-tocopherol and γ-tocotrienol were significantly correlated with p50 (negatively and positively, respectively). While temperate Japonica varieties were most abundant in α-tocopherol, Indica varieties recorded 1.3- to 1.7-fold higher γ-tocotrienol than those of other groups. We conclude that the specific ratio of tocol homologues rather than total tocols content plays an important role in the seed longevity mechanism.

With rapid progress being made in deciphering plant genomic sequences, determining the function of these genes is one of the main challenges that plant molecular biologists face today. Herbicidal inhibitors have been very useful for understanding gene function in at least two examples, represented by herbicidal inhibitors of hydroxyphenylpyruvate dioxygenase (HPPD) and deoxyxylulosephosphate reductoisomerase (DXR). In the first, an albino mutant of Arabidopsis isolated during the study of carotenoid biosynthesis was found to have an intact carotenoid biosynthetic pathway. A number of “bleaching herbicides” in development at about the same time (e.g., sulcotrione) produced similar symptoms by strongly inhibiting HPPD, a key enzyme in plastoquinone biosynthesis. Examination of the Arabidopsis mutant revealed that the HPPD gene had been inactivated in the albino plants. Inhibition of the HPPD pathway also led to reduced levels of tocopherol (vitamin E), an end product of the pathway. Further studies and manipulation of the pathway produced plants with significantly higher levels of vitamin E. This result is a clear demonstration of how an herbicidal inhibitor was able to lead to the identification of a gene that was responsible for a particular phenotype. As a second example, identification of fosmidomycin as a specific inhibitor of DXR in the recently elucidated nonmevalonate pathway of isopentenyl pyrophosphate (IPP) biosynthesis was instrumental in furthering the understanding of an important route to synthesis of many important terpenoid products.

Previous studies have suggested that vitamin E (VE) may affect bone health, but the findings have been inconclusive. We examined the relationship between VE status (in both diet and serum) and bone mineral density (BMD) among Chinese adults. This community-based study included 3203 adults (2178 women and 1025 men) aged 40–75 years from Guangzhou, People’s Republic of China. General and dietary intake information were collected using structured questionnaire interviews. The serum α-tocopherol (TF) level was quantified by reversed-phase HPLC. The BMD of the whole body, the lumbar spine and left hip sites (total, neck, trochanter, intertrochanter and Ward’s triangle) were measured using dual-energy X-ray absorptiometry. In women, the dietary intake of VE was significantly and positively associated with BMD at the lumbar spine, total hip, intertrochanter and femur neck sites after adjusting for covariates (Ptrend: 0·001–0·017). Women in quartile 3 of VE intake typically had the highest BMD; the covariate-adjusted mean BMD were 2·5, 3·06, 3·41 and 3·54 % higher, respectively, in quartile 3 (v. 1) at the four above-mentioned sites. Similar positive associations were observed between cholesterol-adjusted serum α-TF levels and BMD at each of the studied bone sites (Ptrend: 0·001–0·022). The covariate-adjusted mean BMD were 1·24–4·83 % greater in quartile 4 (v. 1) in women. However, no significant associations were seen between the VE levels (dietary or serum) and the BMD at any site in men. In conclusion, greater consumption and higher serum levels of VE are associated with greater BMD in Chinese women but not in Chinese men.

The objective of this study was to evaluate the fatty acid profile and qualitative characteristics of meat from feedlot young bulls fed ground soybean or ground cottonseed, with or without supplementation of vitamin E. A total of 40 Red Norte young bulls, with an initial average age of 20 months, and an initial average BW of 339±15 kg, were allotted in a completely randomized design using a 2×2 factorial arrangement, with two oilseeds, and daily supplementation or not of 2500 IU of vitamin E. The experimental period was for 84 days, which was preceded by an adaptation period of 28 days. The treatments were ground soybean (SB), ground soybean plus vitamin E (SBE), ground cottonseed (CS) and ground cottonseed plus vitamin E (CSE). The percentage of cottonseed and soybean in the diets (dry matter basis) was 24% and 20%, respectively. Diets were isonitrogenous (13% CP) and presented similar amount of ether extract (6.5%). The animals were slaughtered at average live weight of 464±15 kg, and samples were taken from the longissimus dorsi muscle for the measurement of fatty acid concentration and the evaluation of lipid oxidation and color of the beef. Before fatty acid extraction, muscle tissue and subcutaneous fat of the longissimus dorsi were separated to analyze fatty acid profile in both tissues. Supplementation of vitamin E did not affect fatty acid concentration, lipid oxidation and color (P>0.05). Subcutaneous fat from animals fed CS diet had greater C12:0, C16:0 and C18:0 contents (P<0.03). In addition, CS diets reduced the C18:1 and C18:2 cis-9, trans-11 contents in subcutaneous fat (P<0.05). The muscle from animals fed CS tended to higher C16:0 and C18:0 contents (P<0.11), and decreased C18:1, C18:2 cis-9, trans-11 and C18:3 contents (P<0.05) compared with SB. The Δ9-desaturase index was greater in muscle from animals fed SB (P<0.01). At 42 days of age, meat from cattle fed SB had a greater lipid oxidation rate (P<0.05). Meat from animals fed SB diets had less lightness and redness indices than meat from animals fed CS diets after 14 days of age. In conclusion, the addition of ground cottonseed in the finishing diets did increase the saturated fatty acid content of the longissimus dorsi. However, animals fed cottonseed exhibited greater lightness and redness of beef. In this study, the addition of vitamin E did not affect qualitative characteristics of meat.

Weaning of livestock mammals is often associated with digestive problems related to profound changes in the physiology of the gastrointestinal tract. This study was undertaken to study the developmental changes in the gastrointestinal tract of mink kits during the period of 34 to 59 days of age. Twenty-four mink kits from eight litters were included in the experiment. The dams and their litters were kept under standard farm conditions. The dams and the kits were fed a diet consisting of 48.1% protein, 40.7% fat and 11.1% carbohydrate of metabolizable energy. The mink kits were weaned at 42 days of age. At 34, 47 and 59 days of age, one male mink kit from each litter was euthanized. The activity of amylase, trypsin, chymotrypsin and lipase in the pancreatic tissue increased during the experimental period, whereas the activity of carboxyl ester hydrolase remained constant. The vitamin E concentration in plasma was stable from 34 to 59 days of age, whereas the concentration decreased in the liver. The stereochemical composition of α-tocopherol showed a steep decrease in the concentration of the biologically most active natural isomer in both plasma and liver through the whole weaning period, whereas the biologically less active 2S isomers showed a clear increase. The concentration of bile salts did not change during the experimental period. The villous height increased in the proximal part of the small intestine and decreased in the distal part, whereas the crypt depth was doubled in both the proximal and distal part of the small intestine. The mucin-staining area on the villi was markedly reduced during the experimental period but no change in the mucin-staining area in the crypts was observed.

The aim of the present study was to determine the effects of a 6-month dietary vitamin E (VE) deficiency on DNA methylation and gene expression in rat liver. Two enzymes, 5-α-steroid reductase type 1 (SRD5A1) and the regulatory subunit of γ-glutamylcysteinyl synthetase (GCLM), which are differentially expressed on the mRNA level, were analysed for promoter methylation in putative cytosine-phospho-guanine (CpG) island regions located at the 5′ end using base-specific cleavage and matrix-assisted laser desorption ionisation time-of-flight MS. A twofold increase in the mRNA level of SRD5A1 gene and a twofold decrease in the mRNA level of GCLM gene in VE-deficient animals were not associated with different CpG methylation of the analysed promoter region. Furthermore, global DNA methylation was not significantly different in these two groups. Thus, the present results indicate that the VE-induced regulation of SRD5A1 and GCLM in rat liver is not directly mediated by changes in promoter DNA methylation.

Antioxidants protect seeds from oxidative damage during storage, supporting the maintenance of seed viability and the ability to germinate post-storage. No data on antioxidants during long-term storage are available for the seeds of the halophyte Suaeda maritima. Therefore, changes in lipid-soluble antioxidants in the tocopherol family (α-, γ-, δ-tocopherol), were investigated in seeds stored for up to 16 years at 4°C at a seed moisture content of 10–13%, as well as changes in the water-soluble antioxidant glutathione (GSH) and electrolyte leakage. Seed oil content was also measured and determined to be 22%. During the first 3 years of storage, seed viability remained high and the concentration of total tocopherol was stable. Thereafter, both seed viability and α-tocopherol concentration rapidly decreased and electrolyte leakage increased, while γ-tocopherol and δ-tocopherol concentrations did not correlate with seed viability. Although the concentrations of neither GSH nor glutathione disulphide (GSSG) alone were correlated with seed viability, the glutathione half-cell reduction potential (EGSSG/2GSH) was strongly correlated with viability throughout storage and increased before the onset of viability loss. Hence, in this species EGSSG/2GSH appeared to be an ‘early warning’ system preceding viability loss while α-tocopherol concentration changed concomitantly with viability.

We supplemented diets with α-tocopheryl acetate (100 mg/kg) and replaced beef tallow (BT) in feeds with increasing doses of n-6- or n-3-rich vegetable fat sources (linseed and sunflower oil), and studied the effects on the fatty acid (FA) composition, the α-tocopherol (αT) content and the oxidative stability of rabbit plasma and liver. These effects were compared with those observed in a previous study in rabbit meat. As in meat, the content of saturated, monounsaturated and trans FA in plasma and liver mainly reflected feed FA profile, except stearic acid in liver, which increased as feeds contained higher doses of vegetable fat, which could be related to an inhibition of the activity of the stearoyl-CoA-desaturase. As linseed oil increased in feeds, the n-6/n-3 FA ratio was decreased in plasma and liver as a result of the incorporation of FA from diets and also, due to the different performance and selectivity of desaturase enzymes. However, an increase in the dose of vegetable fat in feeds led to a significant reduction in the αT content of plasma and liver, which was greater when the fat source was linseed oil. Increasing the dose of vegetable fat in feeds also led to an increase in the susceptibility to oxidation (lipid hydroperoxide (LHP) value) of rabbit plasma, liver and meat and on the thiobarbituric acid (TBA) values of meat. Although the dietary supplementation with α-tocopheryl acetate increased the αT content in plasma and liver, it did not modify significantly their TBA or LHP values. In meat however, both TBA and LHP values were reduced by the dietary supplementation with α-tocopheryl acetate. The plasma αT content reflected the αT content in tissues, and correlated negatively with tissue oxidability. From the studied diets, those containing 1.5% linseed oil plus 1.5% BT and 100 mg of α-tocopheryl acetate/kg most improved the FA composition and the oxidative stability of rabbit tissues.

Susceptibility to oxidative stress is a well-established feature of the malarial parasite. Pharmacologists have taken advantage of this property to design highly effective pro-oxidant antimalarial drugs. Less well appreciated is the fact that nutritional manipulation of host oxidative stress status by dietary means can have a profound effect on the growth of the parasite. In particular, rapid induction of vitamin E deficiency in mice by feeding highly unsaturated fatty acids (fish oil) strongly suppresses plasmodial growth. Likewise, the status of other antioxidant nutrients (e.g., riboflavin or vitamin C) may also influence the course of malarial infection under certain conditions. A combined nutritional pharmacology approach may offer some promise in controlling malaria.

Berry seeds are a tocopherol-rich by-product of fruit processing without specific commercial value. In a human intervention study, the physiological impact of blackcurrant seed press residue (PR) was tested. Thirty-six women (aged 24 ± 3 years; twenty non-smokers, sixteen smokers) consumed 250 g bread/d containing 8 % PR for a period of 4 weeks (period 3). Comparatively, a control bread without PR (250 g/d) was tested (period 2) and baseline data were obtained (period 1). Blood, stool and 24 h urine were collected during a 5 d standardised diet within each period. Tocopherol and Fe intakes were calculated from food intake. In serum, tocopherol concentration and Fe parameters were determined. In urine, oxidative stress markers 8-oxo-2′-deoxyguanosine, 8-iso-PGF2α and inflammatory response marker 15-keto-dihydro-PGF2α were analysed. Stool tocopherol concentration, genotoxicity of faecal water (comet assay) and antioxidant capacity of stool (aromatic hydroxylation of salicylic acid) were determined. Fe and total tocopherol intake, total tocopherol concentrations in serum and stool, and genotoxicity of faecal water increased with PR bread consumption (P < 0·05). The antioxidant capacity of stool decreased between baseline and intervention, expressed by increased formation of 2,3- and 2,5-dihydroxybenzoic acid in vitro (P < 0·05). In smokers, 8-oxo-2′-deoxyguanosine increased with PR consumption (P < 0·05). Prostane concentrations were unaffected by PR bread consumption. In summary, the intake of bread containing blackcurrant PR for 4 weeks increased serum and stool total tocopherol concentrations. However, various biomarkers indicated increased oxidative stress, suggesting that consumption of ground berry seed may not be of advantage.

The present work was intended to analyse the chemical composition and oxidative stability of the muscle biceps femoris and adipose tissues from Iberian pigs fed different finishing diets: free-range feeding on grass and acorns in a ‘Montanera’ traditional system (MON), fed in confinement with a mixed diet containing high-oleic sunflower oil (115 g/kg of diet) and supplemented with 250 mg/kg α-tocopherol (HOVE), and fed in confinement with a tocopherol-non-supplemented control mixed diet (CON). Muscles from MON pigs contained significantly (P < 0.05) higher amounts of intramuscular fat than those from HOVE and CON pigs. Muscles from MON and HOVE pigs had significantly higher levels of α-tocopherol than muscles from CON pigs whereas free-range feeding provided significantly higher levels of γ-tocopherol to muscles from MON pigs than the experimental diets did to CON and HOVE pigs. Adipose tissues from MON and HOVE pigs contained significantly lower proportions of saturated fatty acids and significantly higher levels of oleic acid and monounsaturated fatty acids than those from CON pigs. Tissues from MON pigs contained significantly smaller levels of polyunsaturated fatty acids than those from CON and HOVE pigs. To a higher extent, feeding background affected the fatty acid composition of polar lipids from the muscle bicepsfemoris than that of neutral lipids. Tissues from MON pigs contained significantly smaller ω-6/ω-3 values than those from pigs fed mixed diets. Compared to tissues from CON pigs, those from MON and HOVE pigs exhibited a higher oxidative stability as a likely result of a most favourable fatty acid composition and the presence of higher tocopherol levels.

At shedding, the moisture content (MC) of Avicennia marina (Forssk.) Vierh. propagules was 65% (fresh mass basis), and there was no significant difference in the MC of four tissues (hypocotyl, cotyledons, plumule and root primordia). Viability declined as the propagules were dried below 60% MC, so that only 40%of seeds were capable of germination at 54% MC. At 47% MC all the seeds had died. The four tissues dried at the same constant rate of 0.02 g water g dwt-1 h–1 throughout this range of MCs. There was no significant depletion of the free-radical-quenching mechanisms measured. In each tissue an organic free-radical was detected by electron paramagnetic resonance (EPR). In the plumule the amplitude of the signal increased by a further 50% at MCs where viability was lost, but there was no increase in the other tissues. There was a concurrent increase in the amount of tocopherol and the activity of superoxide dismutase in the plumule. Lipid peroxidation, assessed by the amount of thiobarbituric acid-reactive substances, also increased in advance of viability loss, suggesting that propagules were experiencing oxidative stress. However, lipid peroxidation decreased at 54–57% MC, where most seeds lost viability. The results presented are consistent with a propagule reacting to oxidative stress, but overtaken by more catastrophic physical damage.

Dietary bioactive compounds (vitamin E, carotenoids, polyphenols, vitamin C, Se and Zn) have beneficial effects on skin health. The classical route of administration of active compounds is by topical application direct to the skin, and manufacturers have substantial experience of formulating ingredients in this field. However, the use of functional foods and oral supplements for improving skin condition is increasing. For oral consumption, some dietary components could have an indirect effect on the skin via, for example, secondary messengers. However, in the case of the dietary bioactive compounds considered here, we assume that they must pass down the gastrointestinal tract, cross the intestinal barrier, reach the blood circulation, and then be distributed to the different tissues of the body including the skin. The advantages of this route of administration are that the dietary bioactive compounds are metabolized and then presented to the entire tissue, potentially in an active form. Also, the blood continuously replenishes the skin with these bioactive compounds, which can then be distributed to all skin compartments (i.e. epidermis, dermis, subcutaneous fat and also to sebum). Where known, the distribution and mechanisms of transport of dietary bioactive compounds in skin are presented. Even for compounds that have been studied well in other organs, information on skin is relatively sparse. Gaps in knowledge are identified and suggestions made for future research.

The biokinetics of newly absorbed vitamin E in blood components was investigated in normolipidaemic males. Subjects (n 12) ingested encapsulated 150 mg 2H-labelled RRR-α-tocopheryl acetate with a standard meal. Blood was collected at 3, 6, 9, 12, 24 and 48 h post-ingestion. 2H-Labelled and pre-existing unlabelled α-tocopherol (α-T) was determined in plasma, lipoproteins, erythrocytes, platelets and lymphocytes by LC–MS. In all blood components, labelled α-T concentration significantly increased while unlabelled decreased following ingestion (P<0·0001). Significant differences in labelled α-T biokinetic parameters were found between lipoproteins. Time of maximum concentration was significantly lower in chylomicrons, while VLDL had a significantly greater maximum α-T concentration and area under the curve (AUC) (P<0·05). The largest variability occurred in chylomicron α-T transport. Erythrocyte labelled α-T concentrations increased gradually up to 24 h while α-T enrichment of platelets and lymphocytes was slower, plateauing at 48 h. Platelet enrichment with labelled α-T was biphasic, the initial peak coinciding with the labelled α-T peak in chylomicrons. Erythrocyte and HDL AUC were significantly correlated (P<0·005), as was platelet and HDL AUC (P<0·05). There was a lower turnover of pre-existing α-T in platelets and lymphocytes (maximum 25 % labelled α-T) compared to plasma and erythrocytes (maximum 45 % labelled α-T). These data indicate that different processes exist in the uptake and turnover of α-T by blood components and that chylomicron α-T transport is a major determinant of inter-individual variation in vitamin E response. This is important for the understanding of α-T transport and uptake into tissues.

Our objective was to study the cross-sectional associations between concentrations of α- and γ-tocopherol and concentrations of glucose, glycosylated haemoglobin, insulin and C-peptide among US adults. We used data for 1289 participants without self-reported diabetes who were aged ≥20 years in the National Health and Nutrition Examination Survey 1999–2000. α-Tocopherol concentration was inversely associated with glucose concentration (β per mmol/l=−0·01064, se 0·00356, P=0·004) after adjusting for age, sex, race or ethnicity, education, smoking status, concentrations of total cholesterol and triacylglycerols, systolic blood pressure, waist circumference, alcohol use, physical activity, time watching television or videos or using a computer, and use of vitamin/mineral/dietary supplements. Among 659 participants who did not report using supplements, this association was no longer significant whereas the concentration of α-tocopherol was inversely associated with concentration of C-peptide (β per mmol/l=−0·01121, se 0·00497, P=0·024). γ-Tocopherol concentration was positively associated with concentration of glucose (β per mmol/l=0·09169, se 0·02711, P=0·001) and glycosylated haemoglobin (β per mmol/l=0·04954, se 0·01284, P<0·001), but not insulin or C-peptide. The relationships between physiologic concentrations of the various forms of vitamin E and measures of glucose intolerance deserve additional investigation.