共轭亚油酸甘油酯对大鼠血清脂肪酸组成影响的研究（英文）

目的:研究共轭亚油酸甘油酯对高脂饮食大鼠血清脂肪酸组成变化的影响;方法:60只SD大鼠随机分为5组:正常对照组、高脂对照组,共轭亚油酸甘油酯低(2 g/kg·bw)、中(4 g/kg·bw)、高(6 g/kg·bw)剂量组,除基础对照组外其余各组均喂饲高脂饲料,建立高脂模型,以灌胃方式给予受试物,6周后取血清测定其脂肪酸组成。采用一步法直接对血清中脂肪酸进行甲酯化,气相色谱毛细管柱分离,氢火焰离子化检测器(FID)定性定量分析;结果:共轭亚油酸甘油酯低、中、高剂量组大鼠血清中单不饱和脂肪酸含量为25.66%,18.74%,17.72%,与高脂对照组相比显著性下降(P0.01),各剂量组饱和脂肪酸和多不饱和脂肪酸含量分别为48.08%,48.52%,51.15%和27.03%,29.28%,31.13%,与高脂对照组相比显著性升高(P0.01)。几种代表性脂肪酸如各剂量组中的油酸、亚油酸与高脂对照组相比分别增加了26.48%,41.56%,51.26%和9.18%,8.61%,8.73%,各剂量组中棕榈酸与高脂对照组相比降低了5.28%,8.80%,10.92%。结论:共轭亚油酸甘油酯能够增加大鼠血清中饱和脂肪酸和多不饱和脂肪酸的含量,减少单不饱和脂肪酸含量,改变血清脂肪酸组成。     

共轭亚油酸甘油酯对大鼠血清脂肪酸组成影响的研究

目的：研究共轭亚油酸甘油酯对高脂饮食大鼠血清脂肪酸组成变化的影响;方法：60 只SD 大鼠随机分为5 组：正常对照 组、高脂对照组,共轭亚油酸甘油酯低（2 g/kg·bw）、中（4 g/kg·bw）、高（6 g/kg·bw）剂量组,除基础对照组外其余各组均喂饲高脂 饲料,建立高脂模型,以灌胃方式给予受试物,6 周后取血清测定其脂肪酸组成。采用一步法直接对血清中脂肪酸进行甲酯化,气 相色谱毛细管柱分离,氢火焰离子化检测器（FID）定性定量分析;结果：共轭亚油酸甘油酯低、中、高剂量组大鼠血清中单不饱和 脂肪酸含量为25.66%,18.74%,17.72%,与高脂对照组相比显著性下降（P<0.01）,各剂量组饱和脂肪酸和多不饱和脂肪酸含量分 别为48.08%,48.52%,51.15%和27.03%,29.28%,31.13%,与高脂对照组相比显著性升高（P<0.01）。几种代表性脂肪酸如各剂量 组中的油酸、亚油酸与高脂对照组相比分别增加了26.48%,41.56%,51.26% 和9.18%,8.61%,8.73%,各剂量组中棕榈酸与高脂对 照组相比降低了5.28%, 8.80%, 10.92%。结论：共轭亚油酸甘油酯能够增加大鼠血清中饱和脂肪酸和多不饱和脂肪酸的含量,减 少单不饱和脂肪酸含量,改变血清脂肪酸组成。     

藏药波棱瓜籽油脂中脂肪酸的HPLC与GC—MS分析

分别采用柱前衍生-高效液相色谱荧光检测法(HPLC-FLD)和气相色谱质谱法(GC-MS),分析了超临界CO2萃取得到的藏药波棱瓜籽油脂中脂肪酸的成分.用荧光衍生试剂1-[2-(对甲苯磺酸酯)乙基]-2-苯基咪唑[4,5-f]9,10-菲(TSPP)作为柱前衍生化试剂对39种饱和与不饱和脂肪酸标品进行衍生,经梯度洗脱实现了39种游离脂肪酸(FFA)衍生物完全分离,使用外标法定量,建立了同时测定39种脂肪酸绝对含量的方法,对超临界CO2萃取结合正交实验得到的波棱瓜籽油样品及超声波萃取与微波回流萃取油脂中的脂肪酸进行了定量分析,对比了这些样品中油酸、亚油酸、亚麻酸的质量百分含量及不饱和脂肪酸占总脂肪酸的含量.结果表明:波棱瓜籽油中油酸、亚油酸、亚麻酸质量百分含量分别高达34.65%(147.14 mg/g,下同)、22.85%(97.03 mg/g)、20.86%(88.56 mg/g),不饱和脂肪酸占总脂肪酸的79%.同时,采用GC-MS分析,对比了酸催化与碱催化的甲酯化法分析波棱瓜籽油中脂肪酸的优劣,得出了GC-MS分析波棱瓜籽油脂肪酸的条件,并讨论了液相色谱与气质联用分析脂肪酸的特点.     

灵芝孢子油脂肪酸组分的分析

采用气相色谱与质谱(GC-MS)联用分析,从超临界CO2萃取孢子油中鉴定出18种脂肪酸成分,包括6种不饱和脂肪酸、7种饱和脂肪酸、2种环链脂肪酸,以及己酸、辛酸、壬酸等短链脂肪酸。GC定量分析结果表明:灵芝孢子油中检出9种已知脂肪酸,不饱和脂肪酸总量为73.6%;其中,主体成分油酸(C18∶1)、亚油酸(C18∶2)和棕榈酸(C16∶0)等含量分别为57.5%、13.4%、19.6%;此外,不饱和脂肪酸十六碳烯酸(C16∶1)、亚麻酸(C18∶3)等不饱和脂肪酸含量为2.2%、0.5%。     

拟茎点霉侵染对采后龙眼果皮LOX活性和膜脂脂肪酸组分的影响

用拟茎点霉(Phomopsis longanae Chi)侵染福眼龙眼(Dimocarpus longan Lour. ‘Fuyan’)果实,研究龙眼果皮脂氧合酶(LOX)活性、膜脂脂肪酸组分和细胞膜透性的变化及其与果皮褐变的关系。结果表明：拟茎点霉侵染导致龙眼果皮褐变指数、LOX活性和细胞膜透性增加,不饱和脂肪酸组分[亚油酸(C18∶2)、亚麻酸(C18∶3)和花生一烯酸(C20∶1)]下降而饱和脂肪酸组分[棕榈酸(C16∶0)和硬脂酸(C18∶0)]增加,脂肪酸不饱和指数(IUFA)和脂肪酸不饱和度下降。拟茎点霉侵染提高龙眼果皮LOX活性和加速膜脂不饱和脂肪酸的降解,从而破坏细胞膜系统的完整性,导致膜系统区室化功能丧失,使多酚氧化酶与酚类物质接触,引起酚类物质的酶促氧化和黑褐色高聚物形成,导致龙眼果皮褐变。     

侧柏叶子与种子脂肪酸的GC-MS比较分析研究

目的:研究柏子仁与侧柏叶的脂肪酸组成.方法:用GC-MS方法对侧柏叶子与种子油进行定性鉴定和定量分析.结果:鉴定了柏子仁油中的8种脂肪酸,占脂溶性成分的93.56%;侧柏叶子油中12种脂肪酸,占脂溶性成分的93.39%.柏子仁饱和脂肪酸主要是十六烷酸(8.11%)、硬脂酸(6.08%);不饱和脂肪酸主要为亚油酸(24.59%)、亚麻酸(59.77%),占脂肪酸的83.14%.侧柏叶子饱和脂肪酸饱和脂肪酸主要为十六烷酸(14.70%)、乙酸(3.20%)、十七烷酸(2.50%);不饱和脂肪酸主要为二十二碳四烯酸(40.48%)、亚油酸(10.69%)、亚麻酸(17.62%).结论:柏子仁和侧柏叶均含有合理的脂肪酸组成.     

柑桔抗寒性与其膜脂脂肪酸组分的关系研究

作者采用气相色谱法对5年生宜昌橙、本地早、国庆一号、锦橙、沙田柚枳砧嫁接树,在抗寒锻炼过程中叶片的膜脂脂肪酸含量的变化进行了研究。结果表明:在日均温为24℃左右时,柑桔叶片开始积累不饱和脂肪酸,冬季叶片不饱和脂肪酸含量最高,比夏季要高60%以上,春季解除抗寒锻炼时,叶片膜不饱和脂肪酸含量下降,饱和脂肪酸含量上升。膜不饱和脂肪酸的积累与气温呈负相关关系。冬季叶片、茎韧皮部和叶绿体等组织器官的膜脂脂肪酸不饱和度、亚麻酸与亚油酸的比值,以及种子中亚油酸与棕榈酸含量之比,均与柑桔品种的抗寒性成正相关。     

八株海洋微藻Nannochloris sp.生长及生化性状评价

通过对从南海海域筛选分离纯化的8株Nannochloris sp.海洋微藻进行生长和生化特性分析,评估该属微藻的生产应用潜力。采用干重法、索氏提取法、凯氏定氮法、苯酚硫酸法、气相色谱质谱联用分别测定微藻生长以及油脂、蛋白质、多糖含量及脂肪酸组成。结果表明,8株微藻的最大生物量干重为0.39-0.91 g/L,生长最快的为SCS-761藻株;总脂含量为(19.06-33.67)%,其中SCS-249、SCS-589、SCS-655藻株总脂含量超过25%,且SCS-655藻株油脂产率高达22.23±0.71 mg/(L·d);SCS-249、SCS-325、SCS-355、SCS-640、SCS-769藻株蛋白质含量超过30%,其中SCS-640藻株蛋白质含量最高(36.70±2.20)%;而各株藻的多糖含量介于19.23%-29.34%,其中SCS-761最高,SCS-655最低。另外,脂肪酸组成分析结果显示8株微藻的脂肪酸组成结构相似,主要为C16饱和脂肪酸和C18系脂肪酸。不饱和脂肪酸以亚油酸相对含量最高,SCS-249、SCS-355、SCS-761藻株亚油酸相对含量超过40%。海洋微藻Nannochloris生物活性物质资源丰富,含有较高的脂质、蛋白质和亚油酸含量,应用潜力可观,应对该属微藻进行更为深入的研究开发,为该属微藻高值化综合性开发奠定基础。     

发菜膜脂及其脂肪酸组成

对野生发菜(Nostocflagelliforme Bom.et Flab)的膜脂(主要成分为类囊体膜脂)及其脂肪酸组成进行了测定分析.发菜的膜脂由单半乳糖甘油二酯(MGDG)、双半乳糖甘油二酯(DGDG)、磷酯酰甘油(PG)和硫代异鼠李糖甘油二酯(SQDG)组成,其酯酰基连接有棕榈酸(16:0)、十六碳烯酸(16:1)、硬脂酸(18:0)、油酸(18:1)、亚油酸(18:2)和亚麻酸(18:3)6种脂肪酸.发菜的不饱和脂肪酸含量可达总脂的73%,特别是16:1和18:3分别高达29%和34%,远远高于已报道的其他蓝藻,说明了发菜类囊体膜具有较强的抗逆性特点.同时还对复水30 min和复水后生长24 h的发菜膜脂及其脂肪酸组成进行了分析.结果表明,复水对野生发菜的膜脂及其脂肪酸组成没有显著影响,说明发菜的膜脂和脂肪酸组成在干燥-吸水过程中能保持很高的稳定性.     

醋豆与大豆中脂肪酸含量的比较及营养学意义

目的:分析比较醋浸泡后大豆中的脂肪酸(FA)含量的变化,为大豆开发提供实验数据.方法:用石油醚提取总脂肪,甲基化后用气相色谱分析脂肪酸的含量分布.结果:醋浸泡28d后,醋豆总脂肪的相对含量趋于稳定,其中醋豆和大豆相比,软脂酸下降了1.21%,硬脂酸下降了0.58%,油酸下降了3.01%,亚油酸增加了1.32%,亚麻酸增加了6.32%.结论:饱和脂肪酸(SFA)和单不饱和脂肪酸的相对含量下降,多不饱和脂肪酸(PUFA)相对含量显著升高.醋大豆及大豆的多不饱和脂肪酸与饱和脂肪酸相对含量的比值分别为4.11和3.2.上述变化的从营养学或生理学的角度,更符合人体需求.     

Responses to oleic,linoleic and α-linolenic acids in high-carbohydrate,high-fat diet-induced metabolic syndrome in rats

We investigated the changes in adiposity, cardiovascular and liver structure and function, and tissue fatty acid compositions in response to oleic acid-rich macadamia oil, linoleic acid-rich safflower oil and α-linolenic acid-rich flaxseed oil (C18 unsaturated fatty acids) in rats fed either a diet high in simple sugars and mainly saturated fats or a diet high in polysaccharides (cornstarch) and low in fat. The fatty acids induced lipid redistribution away from the abdomen, more pronounced with increasing unsaturation; only oleic acid increased whole-body adiposity. Oleic acid decreased plasma total cholesterol without changing triglycerides and nonesterified fatty acids, whereas linoleic and α-linolenic acids decreased plasma triglycerides and nonesterified fatty acids but not cholesterol. α-Linolenic acid improved left ventricular structure and function, diastolic stiffness and systolic blood pressure. Neither oleic nor linoleic acid changed the left ventricular remodeling induced by high-carbohydrate, high-fat diet, but both induced dilation of the left ventricle and functional deterioration in low fat-diet-fed rats. α-Linolenic acid improved glucose tolerance, while oleic and linoleic acids increased basal plasma glucose concentrations. Oleic and α-linolenic acids, but not linoleic acid, normalized systolic blood pressure. Only oleic acid reduced plasma markers of liver damage. The C18 unsaturated fatty acids reduced trans fatty acids in the heart, liver and skeletal muscle with lowered stearoyl-CoA desaturase-1 activity index; linoleic and α-linolenic acids increased accumulation of their C22 elongated products. These results demonstrate different physiological and biochemical responses to primary C18 unsaturated fatty acids in a rat model of human metabolic syndrome.     

Fatty acid synthesis is a target for antibacterial activity of unsaturated fatty acids

Long-chain unsaturated fatty acids, such as linoleic acid, show antibacterial activity and are the key ingredients of antimicrobial food additives and some antibacterial herbs. However, the precise mechanism for this antimicrobial activity remains unclear. We found that linoleic acid inhibited bacterial enoyl-acyl carrier protein reductase (FabI), an essential component of bacterial fatty acid synthesis, which has served as a promising target for antibacterial drugs. Additional unsaturated fatty acids including palmitoleic acid, oleic acid, linolenic acid, and arachidonic acid also exhibited the inhibition of FabI. However, neither the saturated form (stearic acid) nor the methyl ester of linoleic acid inhibited FabI. These FabI-inhibitory activities of various fatty acids and their derivatives very well correlated with the inhibition of fatty acid biosynthesis using [(14)C] acetate incorporation assay, and importantly, also correlated with antibacterial activity. Furthermore, the supplementation with exogenous fatty acids reversed the antibacterial effect of linoleic acid, which showing that it target fatty acid synthesis. Our data demonstrate for the first time that the antibacterial action of unsaturated fatty acids is mediated by the inhibition of fatty acid synthesis.     

不同种源山桐子果实脂肪酸组成变异分析

以采自11个种源的山桐子为材料,测定其果实脂肪酸的组成及其变异情况,结果表明：山桐子果实中不饱和脂肪酸含量较高,尤以亚油酸含量最高,11个种源的平均值为63．58％,且种源间差异显著,分宜、宜昌种源亚油酸相对含量明显高于其他9个种源;饱和脂肪酸以棕榈酸为主,11个种源山桐子果实棕榈酸差异显著,且以平武种源最高;其余脂肪酸含量均较低,变异幅度较大;种子中棕榈酸和棕榈烯酸含量明显高于果肉,而亚油酸、亚麻酸及硬脂酸含量明显低于果肉,油酸含量相近：果实不饱和脂肪酸含量依次为果肉〉全果〉种子,且变异系数及相对极差均较小,尤以果肉中最小;除硬脂酸外,山桐子果实中其他4种主要脂肪酸组分受海拔等地理环境的影响均较小。     

Thematic Review Series: Living History of Lipids: Discovery of essential fatty acids

Dietary fat was recognized as a good source of energy and fat-soluble vitamins by the first part of the 20th century, but fatty acids were not considered to be essential nutrients because they could be synthesized from dietary carbohydrate. This well-established view was challenged in 1929 by George and Mildred Burr who reported that dietary fatty acid was required to prevent a deficiency disease that occurred in rats fed a fat-free diet. They concluded that fatty acids were essential nutrients and showed that linoleic acid prevented the disease and is an essential fatty acid. The Burrs surmised that other unsaturated fatty acids were essential and subsequently demonstrated that linolenic acid, the omega-3 fatty acid analog of linoleic acid, is also an essential fatty acid. The discovery of essential fatty acids was a paradigm-changing finding, and it is now considered to be one of the landmark discoveries in lipid research.     

Growth temperature affects accumulation of exogenous fatty acids and fatty acid composition in <Emphasis Type="Italic">Schizosaccharomyces pombe</Emphasis>

The incorporation of exogenously supplied fatty acids, palmitic acid, palmitoleic acid, oleic acid and linoleic acid, was examined in the yeast Schizosaccharomyces pombe at two growth temperatures, 20 °C and 30 °C. Fatty acids supplied to S. pombe in the growth medium were found to be preferentially incorporated into the cells, becoming a dominant species. The relative increase in exogenous fatty acids in cells came at the expense of endogenous oleic acid as a proportion of total fatty acids. Lowering the temperature at which the yeast were grown resulted in decreased levels of incorporation of the fatty acids palmitic acid, palmitoleic acid and linoleic acid compared to cells supplemented at 30 °C. In addition, the relative amount of the endogenously produced unsaturated fatty acid oleic acid, while greatly reduced compared to unsupplemented cells, was increased in cells supplemented with fatty acids at 20 °C compared to supplemented cells at 30 °C. The differential production of oleic acid in S. pombe cells indicates that regulation of unsaturated fatty acid levels, possibly by control of the stearoyl-CoA desaturase, is an important control point in membrane composition in response to temperature and diet in this species.     

千年桐种子油提取工艺研究及其主要脂肪酸成分分析

本文以氯仿、石油醚和正己烷-异丙醇(3:2,v/v)三种不同溶剂对千年桐种子油进行提取,比较了不同溶剂对种子出油率的影响,结果表明以氯仿为溶剂时出油率最高,达到了35％;并考查了提取时间和提取溶剂体积对出油率的影响.最终优化的提取工艺为:以氯仿为溶剂,液料比为12:1(v/w),提取时间6h,出油率达到了37％.提取的种子油经转酯化后,GC-MS分析其主要脂肪酸组分,结果表明千年桐种子油中总脂肪酸占总油酯的90.55％,其中棕榈酸3.87％,硬脂酸4.11％,亚油酸12.15％,油酸13.31％,亚麻酸12.09％,共轭亚麻酸51.20％和EPA(二十碳五烯酸)3.30％.千年桐种子油中富含不饱和脂肪酸,是一种良好的干性油.     

Manipulation of fatty acid composition of membrane phospholipid and its effects on cell growth in mouse LM cells

Fatty acid composition of the phospholipids of mouse LM cells grown in suspension culture in serum-free chemically defined medium was modified by supplementing the medium with various fatty acids bound to bovine serum albumin.Following supplementation with saturated fatty acids of longer than 15 carbons (100 μM) profound inhibition of cell growth occurred; this inhibitory effect was completely abolished when unsaturated fatty acids were added at the same concentration. Supplementing with unsaturated fatty acids such as linoleic acid, linolenic acid or arachidonic acid had no effect on the cell growth.Fatty acid composition of membrane phospholipids could be manipulated by addition of different fatty acids. The normal percentage of unsaturated fatty acids in LM cell membrane phospholipids (63%) was reduced to 35–41% following incorporation of saturated fatty acids longer than 15 carbon atoms and increased to 72–82% after addition of unsaturated fatty acids.A good correlation was found between the unsaturated fatty acid content of membrane phospholipids and cell growth. When incorporated saturated fatty acids reduced the percentage of unsaturated fatty acids in membrane phospholipids to less than 50%, severe inhibition of the cell growth was found. Simultaneous addition of an unsaturated fatty acid completely abolished this effect of saturated fatty acids.     

Fatty Acid Transport Through the Blood-Brain Barrier

Across the cerebral capillaries, the anatomical locus of the blood-brain barrier, the unidirectional influxes of the saturated fatty acids, octanoic and myristic acids, and the unsaturated essential fatty acid, linoleic acid, were measured. Employing an in situ rat brain perfusion technique that allows control of perfusate composition and accurate measurement of perfusate-to-brain fatty acid transport, we found that both [¹⁴C]octanoic and [¹⁴C]myristic acids were transported through the blood-brain barrier in vivo, in large part, by a specific, probenecid-sensitive transport system. However, the transport of [¹⁴C]linoleic acid was not probenecid sensitive. With 0.5 μM fatty acid but no plasma proteins in the perfusate, the permeability-surface area constant was higher for myristic acid (4.8 × 10^--²× s^-1) than for octanoic and linoleic acids (1.5 and 1.2 × 10^--²× s^-1, respectively). Approximately 70, 30, and 25% of the [¹⁴C]myristic, [¹⁴C]octanoic, or [¹⁴C]linoleic acids, respectively, were extracted from the perfusate.     

破壁马尾松花粉中脂肪酸的成分分析

以石油醚为溶剂,采用索氏抽提法提取破壁马尾松花粉中的粗脂肪,进行甲酯化处理,并用GC-MS技术对脂肪酸甲酯进行分离鉴定,共鉴定出11种脂肪酸;测定其相对含量,不饱和脂肪酸相对含量高达73.14%,其中亚油酸相对含量最高,达36.53%.     

Combined silver-ion and reversed-phase high-performance liquid chromatography for the separation and identification of C20 metabolites of conjugated linoleic acid isomers in rat liver lipids

Reversed-phase high-performance liquid chromatography (RP-HPLC) and silver-ion high-performance liquid chromatography (Ag-HPLC) were successively combined for the separation of the longer-chain metabolites of conjugated linoleic acids (CLAs). Commercial silver nitrate-impregnated columns were used with an eluting solvent composed of a mixture of hexane–acetonitrile. Fatty acid methyl esters (FAMEs) from liver lipids of rats fed CLA were analysed. This method allowed separation both of the non-conjugated FAME, as C16:1, C18:2, C18:3, C20:4 and C22:5, but also the conjugated fatty acids like CLA, 8,12,14-20:3, 5,8,12,14-20:4 and 5,8,11,13-20:4. The presence of 8,11,13-20:3 is reported for the first time. This method is of interest for the isolation and identification of the C₂₀ conjugated metabolites that cannot be resolved by gas chromatography. Furthermore, it allows the isolation of FAME for further characterisation by GC–mass spectrometry (MS).