气相色谱-质谱联用法测定印度楝树油中高级脂肪酸组分含量

对印度楝树油中高级脂肪酸成分进行分析,经甲酯化后用气相色谱-质谱联用仪鉴定了 其中所含高级脂肪酸的成分,用气相色谱法-火焰离子化检测器对其成分进行定量分析.溶剂浸泡萃取和二氧化碳超临界萃取两种不同方法得到的脂肪酸成分基本相同,其中油酸相对含量为51.15%,硬脂酸相对含量为19.13%,棕榈酸相对含量为16.78%,亚油酸相对含量为9.86%,花生酸相对含量为1.24%,其他含量低于1%的高级脂肪酸还有顺-3-辛基-环氧乙烷-辛酸,山萮酸,9-十八(碳)烯酸,11-二十碳二烯酸,9-十六碳烯酸,十七(烷)酸等.     

扁桃油中脂肪酸组成的GC-MS法分析

以正己烷为提取剂,采用超声法提取油脂,经KOH-甲醇甲酯化处理后,以气相色谱-质谱(GC-MS)联用技术鉴定出陕西蒲城3个品种扁桃油中的脂肪酸主要组成为:油酸、亚油酸、9-十六碳烯酸、硬脂酸、棕榈酸,其中不饱和脂肪酸总量占91.4%以上,主要成分油酸占73.3%以上。     

气相色谱-质谱测定红树植物桐花树叶中的挥发油和脂肪酸的组成

采用气相色谱-质谱联用分析法,分析测定了红树植物桐花树AegicerasCorniculatum叶子中挥发油和脂肪酸的成分.结果表明:挥发油中分离出24个峰,鉴定出8种化合物,2,6-二叔丁基-4-甲基苯酚含量丰富,占挥发油总量的20.60%;脂肪酸中分离出16个峰,鉴定出10种脂肪酸,其中主要成分有十六酸(棕榈酸,16.17%)、9,12-十八碳二烯酸(亚油酸,25.73%)、9-十八碳烯酸(油酸,41.52%)等.     

超临界萃取蝼蛄脂肪酸成分及其气相色谱-质谱分析

采用超临界CO2萃取蝼蛄总脂肪酸,对影响萃取效果的各个因素应用正交设计试验,优化了各萃取参数.各个因素的影响顺序为压力＞温度＞时间＞流量.萃取的优化条件为压力35 MPa,温度50℃,时间1 h,流量45 kg/h.运用该萃取条件改善了萃取物的物理性状,脂肪酸的纯度提高,总脂肪酸的含量可达83.29%;而采用常规的有机溶剂提取法,脂肪酸的纯度仅为60%左右.甲酯化采用气相色谱-质谱分析技术对其中的16个成分进行了鉴定,并测定了相对含量,其中主要有油酸甲酯(30.40%)、十六烷酸甲酯(14.19%)、9,12-十八碳二烯酸甲酯(11.99%)、油酸乙酯(11.75%)、9-十六碳烯酸甲酯(7.77%)、十六烷酸乙酯(5.97%)、9,12-十八碳二烯酸乙酯(4.53%)及9-十六碳烯酸乙酯(2.87%)等.     

8种云南植物油脂肪酸的气相色谱-质谱测定

采用气相色谱-质谱联用(GC-MS)方法测定了8种云南植物油脂肪酸含量并对其差异性进行了分析。植物油经甲酯化处理后,用GC-MS方法测定其脂肪酸含量。通过与标准样品保留时间比较和检索NIST标准谱库定性,峰面积归一化法定量。山茶油和辣木籽油含油酸(C18:1)较高,油酸含量分别为80.47%和71.90%;核桃油和假酸浆籽油含亚油酸(C_(18:2))较高,含量分别为60.75%和70.78%;香薷油和藿香籽油含α-亚麻酸(C_(18:3))较高,含量分别为47.13%和55.08%。橡胶树籽油中硬脂酸(C_(18:0))含量9.22%,油酸(C_(18:1))24.07%,亚油酸(C_(18:2))37.17%,α-亚麻酸(C18:3)19.72%,几种脂肪酸分布较为均匀。藿香籽油中不饱和脂肪酸(UFA)含量最高为93.75%。辣木籽油饱和脂肪酸(SFA)含量最高为23.29%;辣木籽油中花生酸(C_(20:0))、二十碳烯酸(C_(20:1))、榆树酸(C_(22:0))和木蜡酸(C_(24:0))含量分别为3.94%、2.73%、6.41%和1.10%,均远远高于其他7种植物油相对应的脂肪酸含量,可作为鉴定辣木籽油的重要依据。     

葵子油脂肪酸2-氨基-2-甲基-丙醇化学修饰气相色谱-质谱分析

以2-氨基-2-甲基-丙醇为脂肪酸的化学修饰试剂,气相色谱一电子轰击质谱（GC-EI MS）分析葵子油脂肪酸。2-氨基-2-甲基-丙醇将脂肪酸羧基修改为含氮杂环,使在EI源中避免了链烯基中碳碳双键的移动。解析了葵子油脂肪酸2-氨基-2-甲基-丙醇化学修饰产物的EI质谱图,讨沦了烯酸中碳碳双键的定位规则,确定了葵子油脂肪酸中碳碳双键的位置。鉴定出葵子油6种脂肪酸,不饱和脂肪酸相对含量为89．41％,其中人体必需脂肪酸9,12-十八碳二烯酸含量占65．30％。本方法为不饱和脂肪酸中双键的定位提供了新的技术手段。     

石榴籽中脂肪酸成分分析

采用两种方法对石榴籽中的脂肪酸进行了甲酯化,所得脂肪酸甲酯经GC-MS分析.方法一共检测出14种脂肪酸,主成分为油酸、亚油酸、山嵛酸、棕榈酸、硬脂酸和二十碳烯酸;方法二共检测出24种脂肪酸,主成分为棕榈酸、硬脂酸、花生酸、山嵛酸、油酸、亚油酸、二十碳烯酸等.其中的山嵛酸等多种饱和脂肪酸均为首次从石榴籽中鉴定出.     

一种氨基哌嗪功能化的丹磺酰氯荧光衍生试剂的合成及其在高效液相色谱法定量分析微藻油脂中的应用北大核心CSCD

自制氨基哌嗪功能化丹磺酰氯(DNS-CL)荧光衍生试剂(DNS-Pi-NH_(2)),并用其衍生化小球藻中碳原子数为10~20的典型脂肪酸[十二烷酸、十四烷酸、顺-9,12-十八(碳)烯酸、顺-7,10,13-十六(碳)烯酸、十六烷酸、顺-9-十八(碳)烯酸、十八烷酸、二十烷酸],用高效液相色谱法(HPLC)测定8种脂肪酸的含量。将小球藻脂肪酸甲酯样品用含氢氧化钾的乙醇溶液于79℃皂化60 min,滴加盐酸溶液,直至酚酞指示剂由红色变为无色。蒸发除去乙醇,所得固体经水清洗、离心、振荡、过滤,即制得小球藻脂肪酸样品。以DNS-CL和N-(2-氨基乙基)哌嗪为原料制备DNS-Pi-NH_(2),并用红外光谱、核磁共振碳谱、质谱对其结构进行表征。取制备好的DNS-Pi-NH_(2)、二丙基二硫醚、三苯基磷的乙腈溶液和1.0 mg小球藻脂肪酸样品在室温下振荡衍生10 min,所得溶液用90%(体积分数,下同)乙腈溶液稀释后,用HPLC测定其中脂肪酸衍生物的含量。以Eclipse XDB C_(8)色谱柱为固定相,以90%乙腈溶液为流动相进行等度洗脱,分离得到的目标物用荧光检测器检测。结果显示:8种脂肪酸衍生物在30 min内可实现完全分离;各脂肪酸的浓度在2.0×10^(-10)~2.0×10^(-4)mol·L^(-1)内与其对应的峰面积呈线性关系,检出限(3s/k)为21~65 pmol·L^(-1);对微藻培养液样品进行加标回收试验,所得回收率为95.3%~102%,测定值的相对标准偏差(n=5)为1.7%~2.6%;方法用于小球藻脂肪酸甲酯样品的分析,检出了十六烷酸、顺-9,12-十八(碳)烯酸、顺-7,10,13-十六(碳)烯酸、顺-9-十八(碳)烯酸,检出量分别为3.08,0.64,0.83,2.57 mg·g^(-1)。     

合成羟基亚油酸异构体的新方法

以亚油酸甲酯为原料,Se O2为催化剂,设计并合成了4个羟基亚油酸异构体——13-羟基-9Z,11E-十八碳二烯酸甲酯,13-羟基-9E,11E-十八碳二烯酸甲酯,9-羟基-10E,12Z-十八碳二烯酸甲酯和9-羟基-10E,12E-十八碳二烯酸甲酯,其结构经1H NMR,13C NMR和LC-MS确证。     

牡丹籽油中脂肪酸的组成分析

用化学萃取法获得牡丹籽油,然后将样品进行皂化、甲酯化,以毛细管气相色谱-质谱联用法(GC-MS)测定牡丹籽油脂肪酸的组成,共鉴定出14种成分,其中主要成分为亚麻酸和亚油酸,其相对含量分别为57.931%和28.121%。     

气相色谱-质谱测定樟林番荔枝种子挥发油的脂肪酸组成

用溶剂萃取法提取樟林番荔枝果实种子中的挥发性物质,测定出其挥发油质量分数为13.3%;利用GC-MS方法分离确认出其中的9种化学成分;用面积归一化法得出了9种脂肪酸在挥发油中的质量分数;其中9-十八烯酸占49.42%,十六酸占20.37%,十八酸占14.16%,9,2-十八二烯酸占13.59%;不饱和脂肪酸,占63.01%.该项研究给番荔枝果实的深入开发利用及种质资源的有效保护提供了科学依据.     

马齿苋及其籽中脂肪酸的比较研究

本实验利用ＧＣ－ＭＳ分析技术对马齿苋全草及其籽中的脂肪酸（以甲酯的形式）进行了分析，共鉴定出８种脂肪酸。全草中以亚麻酸（４７．１６％）、亚油酸（２２．００％）及棕榈酸（１７．４％）为主，籽中以亚油酸（４５．８６％）及亚麻酸（３０．６１％）为主。     

Lipid content and fatty acid composition in lemon wax

Lipids were extracted from lemon wax and fractionated into four classes on a silicic acid glass packed column by thin-layer chromatography (TLC). The free fatty acids, the fatty acid composition and the amount of each separated lipids were determined by capillary column gas chromatography (GC). Total lipids (TL) were 60 mg per 100 g raw weight and the ratio of nonpolar lipids (NPLs): glycolipids (GLs): phospholipids (PLs) was about 47:2:2. The main free fatty acids in lemon wax were hexadecanoic acid, cis-9-octadecenoic acid and cis,cis-9,12-octadecadienoic acid, while in the lipid fractions the main fatty acids were hexadecanoic acid in all the fractions, cis-cis-9,12-octadecadienoic and decanoic acids in triglyceride (TG) fraction, dodecanoic and cis-9-octadecenoic acids in diglyceride (DG) fraction and tetradecanoic, octadecanoic and cis-9-octadecenoic acids in GL and PL fractions. The ratio of unsaturated to saturated fatty acids showed a remarkable difference among these four lipid fractions. In PL and GL fractions this ratio was similar, 47.7% and 47.1% respectively, and in TG fraction it was 42.4% while in DG fraction this value was 23.5%.     

An investigation of frequently consumed edible oils in Turkey in terms of omega fatty acids

The fatty acid profiles of frequently consumed oils and crops cultivated in Turkey were investigated in regard to omega fatty acids. Analyses were carried out on commercially sold oils, sunflower, olive, and fish oils, and oils extracted from fatty seeds of hazelnut, walnut, olive, sunflower, poppy, sesame, and pumpkin, and butter produced in Turkey. Hazelnut and olive oils were found to be rich in omega-9 (oleic acid 18:1), walnut, poppy seed, sesame, and pumpkin seed were rich in omega-6 (linoleic acid 18:2), and butter was rich in short chain fatty acids and omega-9. Fish oil, from mackerel, was the richest in omega-3 fatty acids and fatty acid diversity. There were some alterations between commercially sold oils and oils extracted from seeds in regard to fatty acid percentages and variety.     

Characterization of metabolic pathway of linoleic acid 9-hydroperoxide in cytosolic fraction of potato tubers and identification of reaction products

Potato tubers are shown to contain a unique lipoxygenase pathway to form 9-hydroperoxy-10,12-octadecadienoic acid (9-HPODE) from linoleic acid. Here, we report the metabolic pathway of 9-HPODE in the cytosolic fraction and the characterization of enzymes involved in the conversion of metabolites. The analysis of enzymatic reaction products at pH 5.5 revealed the formation of 9-keto-10,12-octadecadienoic acid, 9-hydroxy-10,12-octadecadienoic acid, 9,10-epoxy-11-hydroxy-12-octadecenoic acid, 9,10,13-trihydroxy-11-octadecenoic acid, and 9,12,13-trihydroxy-10-octadecenoic acid. The cytosolic enzymes were separated by anion-exchange chromatography into two fractions E1 and E2, having molecular masses of 66 and 54 kDa, respectively. The enzyme fraction E1 only produced 9-keto-10,12-octadecadienoic acid, whereas E2 formed other products. The enzyme E1 showed higher reactivity with 13- and 9-hydroperoxide of α-linolenic acid than 9-HPODE, but no reaction with hydroxy fatty acids. In contrast, the enzyme E2 showed the highest reactivity with 9-HPODE, followed by hydroperoxides of α-linolenic acid and arachidonic acid. We also evaluated the antibacterial activity of hydroxy fatty acids against Erwinia carotovora T-29, a bacterium infecting potato tubers. Growth of the bacteria was suppressed more potently with 9- or 13-hydroxy fatty acids than dihydroxy or trihydroxy fatty acids, suggesting a role for the metabolites in the resistance of bacterial infection.     

毛细管气相色谱/质谱法测定柑籽中的脂肪酸

用乙醚/正已烷混合溶剂萃取柑籽中的脂肪酸甘油酯,用KOH-CH_3OH法甲酯化,以毛细管色谱/质谱/计算机法测定其脂肪酸组成,共检出7种脂肪酯,其中以棕榈酸(35.48%)、油酸(26.6%)及亚油酸(27.27%)为主。     

大果白刺游离脂肪酸的柱前衍生高效液相色谱-荧光检测法分析

采用2-（11H-苯[a]咔唑）乙基对甲苯磺酸酯（BCETS）为柱前荧光衍生试剂,通过梯度洗脱使得18种脂肪酸在BDS-C8柱上得到良好的分离.方法应用于大果白刺不同部位中游离脂肪酸的分析,结果表明大果白刺的果皮果肉和叶子中均含有大量的不饱和脂肪酸,其总不饱和脂肪酸含量分别为70.74%和73.47%.大果白刺种子中不饱和脂肪酸的含量相对较少,仅占总脂肪酸含量的57.21%,其不饱和脂肪酸组成主要是C18∶1（油酸）和C18∶2（亚油酸）.其中,大果白刺的果皮果肉中,不饱和脂肪酸主要是C18∶1、C18∶2和C18∶3（亚麻酸）.其叶子中的不饱和脂肪酸主要是C18∶3,所占总脂肪酸比例为48.34%.首次对大果白刺中的脂肪酸进行了分析,可以为大果白刺在食品、药品中的进一步开发应用和质量控制提供一定的数据支持.     

Chemical characterisation of old cabbage (Brassica oleracea L. var. acephala) seed oil by liquid chromatography and different spectroscopic detection systems

We report an extensive chemical characterisation of fatty acids, triacylglycerols, tocopherols, carotenoids and polyphenols contained in the oil extracted from old cabbage (Brassica oleracea L. var. acephala) by cold-pressing of the seeds. Analyses were performed by GC-FID combined with mass spectrometry, HPLC with photodiode array, fluorescence and mass spectrometry detection. The 94% of the total fatty acids were unsaturated, rappresented by erucic acid (more than 50%) followed by linoleic, linolenic and oleic acids accounting for approximately 10% each. The most abundant triacylglycerols (>13%) were represented by erucic–gadolenic–linoleic, erucic–eruci–linoleic and erucic–erucic–oleic. Among tocopherols, γ-tocopherol accounted for over 70% of the total content. Thirteen carotenoids and 11 polyphenols were identified and measured. In particular, the total content in carotenoids was 10.9 ppm and all-E-lutein was the main component (7.7 ppm); among polyphenols, six hydroxycinnamic acids and five flavonoids, were identified by combining information from retention times, PDA and MS data.     

Conjugated ketonic fatty acids from Pleurocybella porrigens

Three novel conjugated long-chain fatty acids (1-3) were obtained from aqueous methanol extracts of Pleurocybella porrigens together with nine known constituents including (8E,10E)-7,12-dioxo-8,10-octadecadienoic acid (ostopanic acid) (4). The structures of the new fatty acids were characterized as (14RS)-(10E,12E)-14-hydroxy-9-oxo-10,12-octadecadienoic acid (1), (12RS)-(8E,10E)-12-hydroxy-7-oxo-8,10-octadecadienoic acid (2), and (10E,12E)-9,14-dioxo-10,12-octadecadienoic acid (3) by spectroscopic methods.     

Rapid reversed-phase high-performance liquid chromatographic determination of the regiospecificity of lipoxygenase products on linoleic acid

A new reversed-phase high-performance liquid chromatography method for the separation of regioisomeric products from lipoxygenase acting on linoleic acid was studied. The addition of salts to the mobile phase improved the retention and separation behaviour of 13-hydroperoxy-9,11-octadecadienoic acid and 9-hydroperoxy-10,12-octadecadienoic acid with respect to the results obtained with other mobile phases reported in the literature. The effect of the pH and ionic strength of the buffer on the retention times, capacity factor and separation factor of these lipoxygenase products were also studied. The pH optimum coincided with the pKa of linoleic acid (close to 7 depending on the fatty acid concentration). Phosphate concentrations close to 100 mM considerably reduced the retention times and led to better separation of the mixture of both products. Finally, this method was applied to the identification and separation of two linoleic acid hydroxides (13-hydroxy-9,11-octadecadienoic acid and 9-hydroxy-10,12-octadecadienoic acid) obtained by the reduction of their corresponding hydroperoxides.