Some compositional properties of seeds and oils of eightAmaranthus species

Grain of 21Amaranthus accessions (eight species) was analyzed for crude fat, fatty acid profiles (FAP), and vitamin E (tocopherols and tocotrienols). Contents of (1→3), (1→4) β-glucan were determined in 12 accessions (four species), and trypsin inhibitor activity (TIA) in 20 accessions (six species). FAP and vitamin E profiles were compared to those of barley, buckwheat, corn, lupin, oat, and wheat oils. Crude fat content ranged from 5.2 to 7.7%, and of the oils examined, amaranth oil was most similar in FAP to corn and buckwheat oils. Amaranth was higher than all but wheat and lupin in tocopherol content but was virtually devoid of tocotrienols, which have been shown to have hypocholesterolemic activity. Amaranth grain did not contain (1→3), (1→4) β-glucans and was low in trypsin inhibitor activity (≤4.3 trypsin units inhibited/mg). Any hypocholesterolemic effects of dietary amaranth are apparently due to substances other than (1→3), (1→4) β-glucans or tocotrienols.     

Vitamin E and its anticancer effects

Abstract

Vitamin E is a lipid soluble vitamin comprising of eight natural isoforms, namely, α, β, δ, γ isoforms of tocopherol and α, β, δ, γ isoforms of tocotrienol. Many studies have been performed to elucidate its role in cancer. Until last decade, major focus was on alpha tocopherol and its anticancer effects. However, major clinical trials using alpha-tocopherol like SELECT trial and ATBC trial did not yield meaningful results. Hence there was a shift of focus to gamma-tocopherol, delta-tocopherol and tocotrienol. Unlike alpha-tocopherol, gamma-tocopherol and delta-tocopherol can scavenge reactive nitrogen species in addition to reactive oxygen species. Antiangiogenic effect, inhibition of HMG CoA reductase enzyme and inhibition of NF-κB pathway make the anti-cancer effects of tocotrienols unique compared to other vitamin E isoforms. Preclinical research on non-alpha tocopherol isoforms of vitamin E showed promising data on their anticancer effects. In this review, we deal with the current understanding on the potential mechanisms involved in the anticancer effects of vitamin E and the controversies in this field over last three decades. We also highlight the need to conduct further research on the anticancer effects of non-alpha-tocopherol isoforms in larger population and clinical setting.     

Profile of Triacylglycerols,Phenols, and Vitamin E of Manjari Medika Grape Seed Oil and Cake: Introducing a Novel Indian Variety

The aim of the study is to investigate the biochemical composition of grapeseed oil and cake from an unexplored Indian grape‐juice cultivar, Manjari Medika (MM). The composition of oil and residual seed cake is evaluated using various chromatographic and spectroscopic techniques. The findings demonstrate that the vitamin E content of MM‐seed oil (1.15–1.35 g kg^?1) is distinctively higher than the Codex standard, suggesting its superior quality as an edible oil. The predominant triacylglycerols include trilinolein (LLL, 43%), dilinoleoyl‐stearylglycerol (LSL, 19%), and dilinoleoyl‐palmitoylglycerol (LLP, 11%), which are earlier recognized as natural antioxidants. The seed‐cake is rich in polyphenols including acylated anthocyanins (e.g., pelargonidin‐3‐O‐coumaroyl glucoside) and certain other flavonoids (e.g., catechin). The profile of phytonutrients in MM seed‐oil and cake is significantly superior to its seeded female parent and two other widely cultivated wine‐grape varieties. In brief, the studied by‐products of this new grape‐juice cultivar can be an important source of high‐value ingredients for use in food supplements, nutraceuticals, and functional foods. Practical applications: This study reports the phytochemical profile of the seed‐oil and seed cake derived from a newly developed grape variety, Manjari Medika. High contents of selective antioxidants: lipids, vitamin E, and phenols in the seed‐oil and cake with health benefits suggest their potential for use in nutraceutical and functional foods. These byproducts can be utilised as ingredients of functional foods and nutraceuticals (e.g., grape seed oil capsule) and also as raw materials in food supply chains (e.g., for production of grape cookies or cake). MM can also be utilized as a colorant in the food industry.     

Tocol Composition and Supercritical Carbon Dioxide Extraction of Lipids from Barley Pearling Flour

Samples of whole grain and 35% pearling flour of 20 different barley varieties grown in Alberta were analyzed for their lipid contents. Total lipid contents of whole grains were within 1.9% to 3.0% (w/w), whereas those of the 35% pearling flour were 4.3% to 7.9%. Lipids of 35% pearling flour fraction of Tercel barley were extracted using supercritical carbon dioxide (SC‐CO₂) at different pressures (24, 45, and 58 MPa) and temperatures (40 and 60 °C) for 3 h. Lipid recoveries of 73% to 97% were achieved using SC‐CO₂ extraction under different operational conditions. Tocol contents and compositions of whole grain, 35% pearling flour, and SC‐CO₂ extracts were analyzed using HPLC. Tocol content of the whole grain was 53.8 to 124.9 μg/g and that of the pearling flour was 195 to 363 μg/g of flour. The hulless barley varieties were higher in tocols, with waxy, double waxy and Tercel varieties having the highest levels (P < 0.05). The ratios of total tocotrienols to total tocopherols varied within 1.6 to 3.9 range. Tocol concentrations of SC‐CO₂ extract fractions varied from 1171 to 4391 μg/g extract depending on the operational conditions. Barley oil is a good natural source of different tocol isomers rich in tocotrienols.     

Detection and quantification of palm mid‐fraction in a chocolate model system

The tocopherol and tocotrienol compositions of the genuine cocoa butter (CB) and palm mid‐fraction (PMF) were investigated to introduce a more reliable indicator in detecting PMF in CB. The results suggested that the α‐tocotrienol data presented could be utilised for the detection of the PMF admixture to CB. The PMF was added to CB at different levels. HPLC was used to detect the presence of PMF admixture to CB using α‐tocotrienol as an indicator. The results derived from the model system indicated that increasing the PMF amount at 0–15% to CB resulted in an increase in the concentration of the α‐tocotrienol significantly (P < 0.05). The addition of PMF amount more than 15% did not have any effect on the α‐tocotrienol concentration. A linear plot with a high correlation of 0.9967 was obtained with SE of 1.527. The high correlation obtained indicated good accuracy, reflecting a close relationship between experimental and theoretical predicted value.     

不同食用植物油中维生素E组分及含量研究

通过对9个不同品种的138个食用植物油样品中维生素E组分及含量的测定,分析研究不同食用植物油中维生素E组分及含量的分布情况。结果表明:9个油脂品种、101个一级油样品中维生素E含量范围为5.9~1 246.6 mg/kg,平均值652.4 mg/kg,维生素E总量的平均值排序为大豆油棉籽油玉米油葵花籽油菜籽油米糠油花生油芝麻油山茶油;不同油脂样品中维生素E的组分有明显差别,米糠油含有最齐全的8种维生素E组分,并且生育三烯酚含量的平均值占维生素E总量平均值的44.2%;玉米油含有3种生育酚和2种生育三烯酚,棉籽油中含有3种生育酚和1种生育三烯酚,但这两种油脂中生育三烯酚含量平均值分别仅占维生素E总量平均值的5.8%和2.8%;大豆油、菜籽油、花生油、葵花籽油均含有α-、γ-、δ-生育酚3种组分;山茶油中含有α-、γ-生育酚2种组分;芝麻油仅含有γ-生育酚1种组分。除芝麻油之外,所有油脂中均含有α-生育酚和γ-生育酚,其中葵花籽油中α-生育酚含量最高,大豆油中γ-生育酚含量最高。同一油脂品种、不同等级的油脂中维生素E含量也存在差异,总体趋势是维生素E含量随油脂精炼程度的加深而降低,但个别二级菜籽油样品中维生素E含量低于一级菜籽油,这与所采集油脂样品的来源不同有关。不同油脂品种、不同等级的食用植物油中维生素E组分及含量因油料品种、油脂精炼工艺的不同显示出明显差异。     

Effect of α‐tocopherol and α‐tocotrienol on the performance of Chilean hazelnut oil (Gevuina avellana Mol) at high temperature

The high temperature antioxidant efficiency of α‐tocopherol, α‐tocotrienol and a mixture of both on hazelnut oil were evaluated. Crude hazelnut oil (HZO), crude hazelnut oil treated with alumina (THZO), as well as three samples of THZO to which 150 mg kg^?1 of α‐tocopherol, 140 mg kg^?1 of α‐tocotrienol or a mixture containing 70 mg kg^?1 of α‐tocopherol and 70 mg kg^?1 of α‐tocotrienol, were added and submitted to thermal treatment at 180°C for 18 h. The addition of tocols to THZO decreased the formation of polar compounds and increased its oxidative stability in all the systems studied. However, α‐tocopherol showed a higher antioxidant capacity than α‐tocotrienol at high temperature. In addition, α‐tocotrienol showed a more rapid degradation rate than α‐tocopherol under the conditions studied. Copyright © 2004 Society of Chemical Industry     

正相高效液相色谱法同时测定食用油中生育酚和生育三烯酚的含量

在GB 5009.82—2016《食品安全国家标准食品中维生素A、D、E的测定》第二法和GB/T26635—2011《动植物油脂生育酚及生育三烯酚含量测定高效液相色谱法》两个国标方法的基础上,结合并优化了两个标准中的测定条件,确定了使用硅胶柱同时测定食用油中α-、β-、γ-、δ-生育酚和α-、β-、γ-、δ-生育三烯酚8种异构体的正相高效液相色谱法。结果表明:样品用90%正己烷+10%甲基叔丁基醚-四氢呋喃-甲醇混合液(体积比20∶1∶0.1)为流动相涡旋振荡溶解10 s后,在用流动相平衡90 min以上的硅胶色谱柱上进行分离,经荧光检测器分析,8种异构体在0.2~10μg/m L范围内线性关系良好,相关系数均大于0.99,检出限均为2 mg/kg,定量限均为6 mg/kg,回收率在70.08%~116.33%之间,相对标准偏差为1.14%~9.85%。优化后方法的回收率和重复性得到了提高,分离效果也有很大改善,能满足食用油中生育酚和生育三烯酚含量同时测定的需要。     

米糠油的营养与应用综述（网络首发、推荐阅读）

米糠油或稻米油从很多方面来看都是一种健康植物油。与其他植物油相比,米糠油具有均衡的脂肪酸,拥有较高含量且独特的微量成分、微量营养素或不皂化物。目前研究表明,米糠油中的谷维素含量超过1.5%,提供了营养和药物功能。更多的研究在开展中来证明米糠油多方面的广泛功能。米糠油富含植物甾醇,有许多研究关注其营养应用价值。此外,米糠油含有生育酚和生育三烯酚,尤其后者具有许多特殊功能,如预防乳腺癌等。越来越多地营养学或生物学研究证明,当米糠油适当加工后在食品中使用时,具有特殊功能。因此,在学术研究和产业实践中,都在探索米糠油在食品和制药领域的应用。对米糠油的营养应用进展做简要综述。     

Kinetic Study of the Scavenging Reaction of the Aroxyl Radical by Eight Kinds of Vegetable Oils in Solution

A detailed kinetic study was performed for the reaction of the aroxyl radical (ArO?) with eight vegetable oils 1–8, which contain different concentrations of α‐, β‐, γ‐, and δ‐tocopherols and ‐tocotrienols (‐Tocs and ‐Toc‐3s). The second‐order rate constants (k_s) and aroxyl radical absorption capacity (ARAC) values for the reaction of ArO? with vegetable oils 1–8 (rice bran 1, perilla 2, rapeseed 3, safflower 4, grape seed 5, sesame 6, extra virgin olive 7, and olive oils 8) were measured in ethanol/chloroform/D₂O (50:50:1, v/v/v) solution at 25 °C using stopped‐flow spectrophotometry. The k_s value (16.1 × 10^?3 L g^?1 s^?1) of rice bran oil 1 with the highest activity was 8.0 times larger than that (2.02 × 10^?3) of olive oil 8 with the lowest activity. The concentrations (in mg 100 g^?1) of α‐, β‐, γ‐, and δ‐Tocs and ‐Toc‐3s contained in the vegetable oils 1–8 were determined using high performance liquid chromatography‐mass spectrometry/mass spectrometry (HPLC‐MS/MS). From these results, it was clarified that the ArO?‐scavenging rates (k_s) (i.e., the relative ARAC value) obtained for the vegetable oils 1–8 may be well explained as the sum of the product of the rate constant () and the concentration ([AOH‐i]/10⁵) of AOH‐i (Tocs and Toc‐3s) included in vegetable oils. The results suggest that the ARAC assay method might be used in the evaluation of antioxidant activity of general food extracts.