comparison between tocotrienol and omeprazole on gastric growth factors in stress-exposed rats

AIM To investigate and compare the effects of tocotrienol and omeprazole on gastric growth factors in rats exposed to water-immersion restraint stress(WIRS).METHODS Twenty-eight male Wistar rats were randomly assigned to four groups of seven rats. The two control groups were administered vitamin-free palm oil(vehicle) and the two treatment groups were given omeprazole(20 mg/kg) or tocotrienol(60 mg/kg) by oral gavage. After 28 d of treatment, rats from one control group and both treated groups were subjected to WIRS one time for 3.5 h. Gastric lesions were measured and gastric tissues were obtained to measure vascular endothelial growth factor(VEGF), epidermal growth factor(EGF), basic fibroblast growth factor(b FGF), and transforming growth factor-alpha(TGF-α) m RNA expression. RESULTS Rats exposed to WIRS for 3.5 h demonstrated the presence of considerable ulcers in the form of gastric erosion. The lesion index in the stressed control(S) group was increased(P < 0.001) compared to the tocotrienol treated and omeprazole treated groups. Stress led to a decrease in gastric VEGF(P < 0.001), b FGF(P < 0.001) and TGF-α(P < 0.001) m RNA levels and caused an increase in EGF m RNA(P < 0.001) that was statistically significant compared to the nonstressed control group. Although both treatment agents exerted similar ulcer reducing ability, only treatment with tocotrienol led to increased expression of VEGF(P = 0.008), b FGF(P = 0.001) and TGF-α(P = 0.002) m RNA.CONCLUSION Tocotrienol provides gastroprotective effects in WIRSinduced ulcers. Compared to omeprazole, tocotrienol exerts a similar protective effect, albeit through multiple mechanisms of protection, particularly through up-regulation of growth factors that assist in repair of gastric tissue injuries.

Tumor-targeted niosome as novel carrier for intravenous administration of tocotrienol

Tocotrienol(T3),the unsaturated form of vitamin E,has gained global attention due to its potent anticancer effects against a wide range of cancers.Found abundantly in palm oil[1],T3was reported to exhibit their anti-cancer properties via various pathways including anti-proliferative,anti-angiogenesis,antiinflammatory,apoptosis and improvement of immunological function[2].However,the lack of tumor specificity and rapid body clearance have restricted the clinical applications of T3[3].

Preparation and optimization of tocotrienol rich fraction(TRF)-loaded niosomes

Vesicular delivery systems have gainedmuch attention as pharmaceutical entities since their discovery.Niosomes occupy the general structure of bilayer vesicles,having a hydrophilic core shielded from one or multiple hydrophobic lipid bilayer.This unique structure enables them to both accommodate oilsoluble compounds as well as to encapsulate water-soluble drugs[1].The anticancer effects of tocotrienol were first discovered in the early 1990s when Nesaretnam et al.reported that palm oil stripped of vitamin E-promoted tumorigenesis in rats[2].

The Antioxidant Activity of Tocotrienols Compared with Some Synthetic Antioxidant

The changes in content of fatty acids were studied every three months along the storage’s period, after adding an equal concentration (200 mg/Kg) of the natural antioxidant Tocotrienols (α-, β-, γ- and δ-T3) and of the synthetic one (BHT, BHA, AP) to four samples of different vegetable oils (sunflower oil, soybean oil, corn oil and olive oil). Then the oxidized and non-oxidized FAMEs were calculated to determine the antioxidant activity (AOA). The results showed that there was difference in AOA depending on the antioxidant of used. Tocotrienols were relatively weak compared with the synthetic antioxidant in all different types of oil. The AOA for each antioxidant was differed in different oil types. It was the most in the sunflower oil compared with the rest different oil types, while it was the lower for corn oil for all antioxidant. The AOA for BHA was the highest for different oil types compared with other antioxidants, and the δ-T3 had the lowest, while the rest anti-oxidants were in the following order: (BHA, BHT, AP, α-T3, β-T3, γ-T3, δ-T3).

Tocotrienol isoforms:The molecular mechanisms underlying their effects in cancer therapy and their implementation in clinical trials

Tocotrienols are found in a variety of natural sources,like rice bran,annatto seeds and palm oil,and have been shown to have several health-promoting properties,particularly against chronic diseases such as cancer.The incidence of cancer is rapidly increasing around the world,not only a result of continued aging and population growth,but also due to the adoption of aspects of the Western lifestyle,such as high-fat diets and low-physical activity.The literature provides strong evidence that tocotrienols are able to inhibit the growth of various cancers,including breast,lung,ovarian,prostate,liver,brain,colon,myeloma and pancreatic cancers.These findings,along with the reported safety profile of tocotrienols in healthy human volunteers,encourage further research into these compounds’potential use in cancer prevention and treatment.The current review provided detailed information about the molecular mechanisms of action of different tocotrienol isoforms in various cancer models and evaluated the potential therapeutic effects of different vitamin E analogues on important cancer hallmarks,such as cellular proliferation,apoptosis,angiogenesis and metastasis.MEDLINE/PubMed and Scopus databases were used to identify recently published articles that investigated the anticancer effects of vitamin E derivatives in various types of cancer in vitro and in vivo along with clinical evidence of adjuvant chemopreventive benefits.Following an overview of pre-clinical studies,we describe several completed and ongoing clinical trials that are paving the way for the successful implementation of tocotrienols in cancer chemotherapy.

Antioxidant status following postprandial challenge of two different doses of tocopherols and tocotrienols

Objective:Tocotrienols(T3s)have been hypothesized to have greater antioxidant capacity than tocopherols(Ts)due to differences in biokinetics that affect their absorption and function.The present trial compares the antioxidant effectiveness following postprandial challenge of two different doses ofα-T or palm T3-rich fraction(TRF)treatments and evaluates their dose-response effects on antioxidant status.Methods:Ten healthy volunteers were given four different doses of vitamin E formulations(268 mgα-T,537 mgα-T,263 mg TRF or 526 mg TRF)in a cross-over postprandial trial.Blood was sampled at 0,2,4,5,6 and 8 hours after meal consumption and plasma antioxidant status including total glutathione,superoxide dismutase,malondialdehyde(MDA),ferric reducing antioxidant potential and trolox-equivalent antioxidant capacity,was analyzed.Results:Supplementation with the different doses of eitherα-T or TRF did not significantly improve overall antioxidant status.There was no significant difference in overall antioxidant status among treatments at the different doses compared.However,a significant dose-response effect was observed for plasma MDA throughout the 8-hour postprandial period.MDA was significantly lower after the 537 mgα-T treatment,compared to the 268 mgα-T treatment;it was also lower after the 526 mg TRF treatment compared to the 263 mg TRF treatment(P<0.05).Conclusion:T3 andα-T demonstrated similar antioxidant capacity,despite markedly lower levels of T3 in blood and lipoproteins,compared toα-T.

GC-MS/MS测定植物油中生育酚和生育三烯酚

建立一种气相色谱-串联质谱法(GC-MS/MS)同时测定植物油中α-、β-、γ-、δ-生育酚和α-、β-、γ-、δ-生育三烯酚含量的方法。样品经异辛烷超声提取后,采用动态多反应监测离子模式分析。结果表明:8种维生素E异构体可实现基线分离,在1~500 ng/mL范围内,线性关系良好,相关系数均大于0.999,检出限和定量限分别为0.02~0.05 mg/kg和0.10 mg/kg,平均回收率为81.5%~109.5%,相对标准偏差为3.3%~7.2%。方法快速、简便、准确、灵敏度高,适用于植物油中生育酚和生育三烯酚含量的测定。

4种油脂煎炸过程中维生素E组分含量变化的研究

用米糠油、大豆油、棕榈油、米糠调和油进行连续煎炸油条试验,通过对不同煎炸时间所取油样中维生素E各组分含量及酸值、羰基价、极性组分含量的检测,分析研究这4种油脂在煎炸过程中维生素E各组分含量的变化及其对油脂煎炸稳定性的影响。结果表明:4种油脂初始维生素E含量大小依次为大豆油>米糠油>米糠调和油>棕榈油,生育三烯酚含量占维生素E总量大小依次为米糠调和油>米糠油>棕榈油>大豆油;随着煎炸时间延长,4种油脂中维生素E含量均持续快速降低,至煎炸32 h结束时,维生素E损失率为大豆油77.12%、米糠油97.93%、棕榈油100%、米糠调和油93.86%;米糠油虽不如大豆油的维生素E含量高(为大豆油的51.13%),但因富含生育三烯酚(为大豆油的7.2倍),使其极性组分含量及羰基价增幅均小于大豆油,表现出良好的煎炸稳定性。

测定裸大麦中生育酚和生育三烯酚的正相高效液相色谱法

建立了同时测定裸大麦中α_、β_、δ_生育酚和α_、γ_、δ_生育三烯酚以及γ_生育酚 +β_生育三烯酚含量的正相高效液相色谱法;采用国产YWG_SiO2 柱 (250mm×4mmID ,5μm) ,V 正己烷∶V 异丙醇=99∶1体系为流动相 ,流速为1.2mL/min,荧光检测器检测 ,激发波长290nm ,发射波长330nm,并采用正交设计法优化样品的皂化工艺。

维生素E抗油脂氧化的功能探讨

抗氧化功能是维生素Ｅ的一种基本功能。维生素Ｅ特殊的化学结构与性质使得它既能抗油脂自动氧化，又具有一定的淬灭１Ｏ２的能力。本文根据目前公认的油脂氧化机理，就维生素Ｅ抗油脂氧化的机理与具体功能进行了探讨，并且介绍了一些常见油脂中的ＰＵＦＡ与维生素Ｅ的水平。

不同基因型大麦品种大麦油及其母育酚含量的变异规律

为了探讨不同基因型大麦品种大麦油及其母育酚含量的变异规律,采用超临界萃取法及HPLC法提取并测定了30个大麦品种的大麦油及其母育酚含量和成分。结果表明,大麦油含量存在显著的基因型和环境效应(P<0.05),裸大麦的大麦油含量(平均为4.16%)高于皮大麦(平均为2.96%),蜡质裸麦品种(Sumire mochi)含量最高(6.15%)。与去皮籽粒相比,全麦的大麦油含量较高;与麦芽相比,制啤后的大麦原料仍有较高的母育酚含量。大麦油的母育酚组成成分主要为α-生育酚(占总生育酚的65.4%)和α-生育三烯酚(占总生育三烯酚的70.7%)。试验表明,大麦油及其母育酚含量既受基因型的控制,又受生长环境条件的影响;大麦种皮部分可能是大麦油的主要储存组织之一,制啤后的大麦原料有可能作为母育酚提取的资源加以利用,从而提高大麦的附加值。

米糠油及其脱臭馏出物中生育酚和生育三烯酚的分析检测

对米糠油及其脱臭馏出物中生育酚及生育三烯酚含量进行检测分析,结果表明,米糠来源和米糠油精炼工艺对米糠油及其脱臭馏出物中α、β、γ、δ-生育酚和生育三烯酚的含量有显著影响。米糠毛油中生育三烯酚占维生素E总量的60%～70%,脱臭馏出物中生育三烯酚占维生素E总量的25%～40%,米糠油脱臭馏出物维生素E总量中生育三烯酚的含量较米糠毛油有较大的损失。通过对米糠油脱臭馏出物不皂化物的分析检测可知,米糠油脱臭馏出物中主要甾醇的种类为豆甾醇、菜油甾醇、谷甾醇,总甾醇含量很少,仅为0.32%;除此之外,还有少量日耳曼甾醇、羊毛甾醇、3,5-二烯豆甾烷等。

生育三烯酚的研究进展

综述了近 10年来生育三烯酚的研究进展。具体介绍了生育三烯酚的结构、粮食和油脂中的含量、提取纯化技术及生理功能。

棕榈油中生育酚和生育三烯酚的HPLC测定

建立了棕榈油中生育酚和生育三烯酚的准确、快速的HPLC分析方法。选用Nucleosil硅胶柱正相分离,以正己烷-异丙醇为流动相,梯度洗脱,在紫外波长292nm下进行检测,获得较理想的分离效果。该方法线性范围为0.2275～1.3031mg/mL,平均加样回收率为100.17%,RSD=0.5905%。

常见食用植物油中维生素E异构体含量调查研究

通过查阅国内外官方食物成分数据库,同时综合近年来国内对成品食用植物油中不同生育酚和生育三烯酚含量进行分析的文献,建立常见食用植物油维生素E异构体成分表。结果表明:国内外现有数据库中食用植物油种类及其生育酚和生育三烯酚数据均不全,且不同地区含量存在明显差异。通过对国内最新研究汇总,共收集22种合计659个常见食用植物油的α-、β-、γ-、δ-生育酚数据,同时收集17种合计183个食用植物油的α-、(β+γ)-、δ-生育三烯酚数据。生育酚广泛存在于植物油中,以α-生育酚和γ-生育酚为主,但不同植物油中含量情况存在明显差异;生育三烯酚主要存在于棕榈油、米糠油和葡萄籽油中,在其他植物油中分布很少。不同类型食用植物油的选择会明显影响人体活性VE总量和不同异构体的摄入情况,目前国内外食用植物油VE异构体数据库有地区差异且均不能覆盖目前常见的食用植物油种类,更新常见成品食用植物油VE数据库很有必要。

水稻籽粒维生素E及组分在品种间的变异与分布

维生素E是人与动物必须从食物中摄取的微量营养元素之一,根据侧链的饱和度可将其分为生育酚和三烯生育酚,水稻种子中均含二者。本研究利用反相高效液相色谱法测定了18份籼稻和16份粳稻品种糙米中维生素E各异构体的含量。结果表明,种子中各异构体的含量在籼稻与粳稻间存在显著差异,粳稻种子中的生育酚和维生素E含量高于籼稻;籼稻种子中三烯生育酚与生育酚的比值(1.61)极显著高于粳稻(0.95),籼稻中以γ-三烯生育酚为主,而粳稻中主要含α-生育酚。水稻种子中同种类型异构体(即α-型间或γ-型间)含量间具有显著正相关,但γ-型与α-型异构体间呈显著负相关。这些数据为进一步研究水稻种子中维生素E的代谢调控和营养品质改良提供了有益的表型数据。

裸大麦中生育三烯酚的超临界CO_2流体萃取工艺

采用四元二次通用旋转设计研究了裸大麦中生育三烯酚的超临界CO2流体萃取工艺。结果表明:萃取温度对生育三烯酚提取率有显著影响,乙醇添加量和萃取时间对生育三烯酚提取率有极显著影响,而萃取压力对生育三烯酚提取率无显著影响,但萃取压力和乙醇添加量的交互项对生育三烯酚提取率有显著影响;在本实验条件下,生育三烯酚最佳超临界CO2萃取条件为:萃取温度51.8℃、萃取压力34.7MPa、乙醇添加量9%、萃取时间120min。

天然维生素E的检测技术研究进展

天然维生素E是植物油中普遍存在的一类抗氧化剂,因其具有安全、高效、无毒等优点被人们广泛关注。近年来,随着天然维生素E在食品、饲料、医药、化妆品等领域的逐步应用,其检测和品控技术也在不断发展,研究人员根据维生素E的物理、化学性质开发了多种检测方法。本文主要简述了色谱技术、光谱技术以及电化学分析技术等在天然维生素E检测中的应用,探讨了这些分析方法的基本原理以及优缺点,比较了各方法的灵敏度、准确性和检测极限等指标,便于在分析实际样品时选择最合适的测定方法。

生育三烯酚分离纯化研究进展

生育三烯酚是一种高品质的天然维生素E,具有广阔的开发前景和市场需求。介绍了生育酚及生育三烯酚的来源,重点论述了生育酚及生育三烯酚分离纯化的常用方法、相关技术路线及其对应的优缺点和适用范围。结果表明:离子交换法选择性高,特异性强,适合提取高含量的生育酚及生育三烯酚;柱色谱法仪器设备简单,理论上是分离生育酚和生育三烯酚的有效方法,但普遍存在洗脱时间过长、溶剂消耗量大等问题;超临界流体色谱在制备生育三烯酚及其单体方面具有良好的应用前景。最后介绍了当前国内外生育三烯酚的产业化情况,以期为今后国内生育三烯酚深入研究提供一定的参考。

棕榈油脱臭馏出物中生育酚及生育三烯酚的测定

建立的高效液相色谱法快速、准确测定棕榈油脱臭馏出物中生育酚及生育三烯酚同系物的含量。选用LiChrospher 100 Diol色谱柱(4.0 mm×250 mm,5μm),以正己烷和四氢呋喃为流动相(96∶4,V∶V),流速1.0 mL/min,柱温30 oC,VWD检测器,在紫外波长292 nm下测定。结果显示四种生育酚及四种生育三烯酚均能达到基线分离,获得很好的分离效果,该方法线性范围为0.2μg/mL～0.6 mg/mL,最底检测线浓度为0.05776 ug/mL,操作简便,重复性好,样品不需特殊处理,适合用于棕榈油脱臭馏出物中生育酚及生育三烯酚同系物含量的测定。