Roasting effects on fatty acid distributions of triacylglycerols and phospholipids in sesame (Sesamum indicum) seeds

Sesame seeds were roasted at different temperatures (180–220 °C) using a domestic electric oven. The positional distribution of fatty acids in triacylglycerols (TAGs) and phosphatidylcholine (PC) isolated from total lipids in these seeds was investigated as well as the naturally occurring antioxidants that are present. Major lipid components were TAGs and phospholipids (PLs), while steryl esters (SEs), free fatty acids (FFAs) and sn‐1,3‐ and sn‐1,2‐diacylglycerols (DAGs) were minor ones. Following roasting, a significant increase (P < 0.05) was observed in FFAs and in both forms of DAG (primarily sn‐1,3‐DAG). The greatest PL losses (P < 0.05) were observed in phosphatidylethanolamine (PE), followed by PC and phosphatidylinositol (PI). On the other hand, the amounts of γ‐tocopherol and sesamin remained at over 80 and 90% respectively of the original levels after roasting at 220 °C. The principal characteristics of the positional distribution of fatty acids were still retained after 25 min of roasting: unsaturated fatty acids, especially linoleic and/or oleic, were predominantly concentrated in the sn‐2‐position, and saturated fatty acids, especially stearic and/or palmitic, primarily occupied the sn‐1‐ or sn‐3‐position. The results suggest that unsaturated fatty acids located in the sn‐2‐position are significantly protected from oxidation during roasting at elevated temperatures. © 2001 Society of Chemical Industry     

基于脂肪酸谱法分析山茶油掺伪

为了更好的检测市售山茶油中的掺混,本研究基于气相色谱-质谱联用技术(GC-MS)建立了一种检测山茶油中掺入其他低值植物油的方法。实验采用GC-MS检测了市售山茶油、芝麻油、花生油以及玉米油的脂肪酸组成,并对其脂肪酸成分进行比较,建立鉴别山茶油中掺混这几种植物油的方法以及掺假比例的预测与验证。结果表明,GC-MS检测出上述几种植物油的脂肪酸组成,其中主要的脂肪酸为棕榈酸、硬脂酸、油酸与亚油酸,其中山茶油的油酸含量高达78.8058%,实验检测山茶油中掺入低值油比例为10%、20%、30%、45%的掺假油,且根据特定的油酸的含量建立的回归方程的相关系数均大于0.98。因此根据该方法可以用于山茶油中掺入一种低值植物油的检测,最低检测掺入量为10%,且方法快速方便、且方法的准确率高于97%,较为灵敏。     

贵州茶油气相色谱脂肪酸标准指纹图谱构建及其鉴别

目的 基于气相色谱法(gas chromatography,GC)构建油茶籽油脂肪酸的气相指纹图谱。方法 以贵州产油茶籽为研究对象，采用气相分析不同产地、品种及加工方式共计34批次油茶籽油的脂肪酸组成。结果 确定棕榈酸、硬脂酸、油酸、亚油酸、花生一烯酸和亚麻酸为油茶籽油的主要脂肪酸。通过“中药色谱指纹图谱相似度评价系统”建立了油茶籽油气相色谱标准指纹图谱，并与菜籽油、葵花籽油、芝麻油、玉米油、米糠油、花生油、棕榈油和高油酸花生油等8种植物油进行相似度比较，除菜籽油和高油酸花生油因相似度大于0.95而无法与油茶籽油进行区分外，其余6种油脂均可识别为非油茶籽油。结论 通过对贵州产油茶籽油脂肪酸组成和标准指纹图谱的建立，可为纯茶油的真伪鉴别提供了一定的试验数据支撑     

Generation of glycerophospholipid molecular species in the yeast Saccharomyces cerevisiae. Fatty acid pattern of phospholipid classes and selective acyl turnover at sn-1 and sn-2 positions

Acyl chains linked to phospholipids of the yeast, Saccharomyces cerevisiae, are mainly C16:1 and C18:1 accompanied by minor amounts of C14:0, C16:0 and C18:0. In view of this rather simple fatty acid composition, the question arose whether in yeast, as in higher eukaryotes, fatty acyl groups were characteristically distributed among the sn-1 and sn-2 positions of distinct phospholipid classes. Analysis of fatty acids linked to the sn-1 and sn-2 positions of the major phospholipids showed that indeed saturated fatty acyl groups predominated in the sn-1 positions. While the percentage of saturated fatty acids was low (10%) in phosphatidylcholine (PtdCho) and phosphatidylethanolamine (PtdEtn) from cells grown on rich medium, it was higher in phosphatidylserine (PtdSer) (25%) and highest in phosphatidylinositol (PtdIns) (41%). Oleate was mainly linked to position sn-2, while palmitoleate predominated in position sn-1. Striking differences in the fatty acid distribution of phospholipids that are metabolically closely related (e.g. PtdSer and PtdEtn, PtdEtn and PtdCho, and PtdIns and PtdSer) suggest that pathways must exist for the generation of distinct phospholipid molecular species within the different phospholipid classes. The highly selective incorporation of exogenous [¹⁴C]palmitic acid (90%) and [³H]oleic acid (99%) into the sn-2 position of PtdCho, and the preferential incorporation of these fatty acids into the sn-2 position of PtdEtn (70 and 90%, respectively, for palmitic and oleic acid) are compatible with the postulate that phospholipase A₂-mediated deacylation followed by reacylation of the lysophospholipids is involved in the generation of phospholipid species in yeast.     

Distribution of fatty acids in triacylglycerols and phospholipids from peas (Pisum sativum L.)

BACKGROUND: The fatty acid distribution of triacylglycerols (TAG) and major phospholipids (PL) obtained from four varieties of peas (Pisum sativum) was investigated. The total lipids extracted from the peas were separated by thin layer chromatography into seven fractions. RESULTS: The major lipid components were PL (52.2–61.3%) and TAG (31.2–40.3%), while hydrocarbons, steryl esters, free fatty acids and diacylglycerols (sn‐1,3 and sn‐1,2) were also present in minor proportions (5.6–9.2%). The main PL components isolated from the four varieties were phosphatidylcholine (42.3–49.2%), phosphatidylinositol (23.3–25.2%) and phosphatidylethanolamine (17.7–20.5%). Significant differences (P < 0.05) in fatty acid distribution were found for different pea varieties. Phosphatidylinositol was unique in that it had the highest saturated fatty acid content among the three PL. However, the principal characteristics of the fatty acid distribution in the TAG and three PL were evident among the four varieties: unsaturated fatty acids were predominantly located in the sn‐2 position while saturated fatty acids primarily occupied the sn‐1 or sn‐3 position in the oils of the peas. CONCLUSION: These results should be useful to both producers and consumers for the manufacture of pea foods in Japan. Copyright © 2007 Society of Chemical Industry     

Production and structural analysis of triacylglycerols containing capric acid and conjugated linoleic acid isomers obtained by enzymatic acidolysis

BACKGROUND: Structured lipids containing medium‐chain fatty acids have interesting applications as reduced‐calorie fats; moreover, conjugated linoleic acid (CLA) isomers have shown interesting biological properties. The aim of this study was to synthesize triacylglycerols (TAGs) containing capric acid in the sn‐1‐ and sn‐3‐ positions and CLA isomers in the sn‐2‐ position, using different commercial available lipases. RESULTS: The homogeneous CLA‐TAGs (Tri‐CLA) were chemically synthesized starting from glycerol and CLA isomers, 9‐cis,11‐trans and 10‐trans,12‐cis CLA. The acidolysis reactions of Tri‐CLA with capric acid were carried out at 55 °C for different times in hexane; after 96 h the acidolysis average yield was 65%. The best capric acid incorporation in total TAGs was obtained after 96 h with Lipozyme IM (56.6%). The results of structural analysis carried out on the obtained TAGs showed that both Novozyme 435 and anhydrous Lipozyme IM gave the best incorporation of capric acid in sn‐1(3)‐ positions (61.8%). However, anhydrous Lipozyme IM gave also the highest CLA percent content in sn‐2‐ position (73.2%). CONCLUSION: Anhydrous Lipozyme IM appears to be the more effective enzyme in acidolysis reactions to obtain structured TAGs containing CLA isomers in the central position and capric acid at external positions. Copyright © 2009 Society of Chemical Industry     

Intramuscular Lipids and Triglyceride Structures in Range and Feedlot Steers

Longissimus muscle of feedlot steers contained less moisture and more triglycerides (TG) but similar amounts of cholesterol and lipid phosphorus when compared to muscle of range steers. A 100-g portion of the muscle from feedlot steers provided more of all fatty acids analyzed except iso- and anteiso-tridecanoic and pentadecanoic acids (br 13:0, br 15:0) and octadecatrienoic acid (18:3). Structures of the intramuscular TG were not influenced by dietary treatment. Medium chain saturated acids (10:0 to 15:0) were distributed throughout all 3 positions, 16:0 predominated in the sn-1 position, 18:0 and 20:0 in the sn-1 and sn-3 positions. Br 13:0 and br 15:0 predominated in the sn-2 position and were essentially absent from the sn-3 position. Monounsaturated acids, with the exception of trans octadecenoic acid (trans 18:1), were found mainly in the sn-2 and sn-3 positions. Trans 18:1 predominated in the sn-1 and sn-3 positions thereby resembling a long chain saturated acid, Octadecadienoic acid (18:2) and 18:3 were about equally divided between positions sn-2 and sn-3. Tram 18:1 comprised 1.9 and 1.3% of total intramuscular fatty acids from range and feedlot steers, respectively. The structures of intramuscular TG, with respect to 18:2 and saturated acids, did not resemble those of native peanut oil which has been reported to be more atherogenic than randomized peanut oil.     

Enzymatic Synthesis of Refined Olive Oil‐Based Structured Lipid Containing Omega ‐3 and ‐6 Fatty Acids for Potential Application in Infant Formula

Structured lipids (SLs) containing palmitic, docosahexaenoic (DHA), and gamma‐linolenic (GLA) acids were produced using refined olive oil, tripalmitin, and ethyl esters of DHA single cell oil and GLA ethyl esters. Immobilized Lipozyme TL IM lipase was used as the biocatalyst. The SLs were characterized for fatty acid profile, triacylglycerol (TAG) molecular species, solid fat content, oxidative stability index, and melting and crystallization profiles and compared to physical blend of substrates, extracted fat from commercial infant formula (IFF), and milk fat. 49.28 mol% of palmitic acid was found at the sn‐2 position of SL TAG and total DHA and GLA composition were 0.73 and 5.00 mol%, respectively. The total oleic acid content was 36.13 mol% which was very close to the 30.49% present in commercial IFF. Comparable solid fat content profiles were also found between SLs and IFF. The SLs produced have potential for use in infant formulas.     

Camphor Tree Seed Kernel Oil Reduces Body Fat Deposition and Improves Blood Lipids in Rats

The total and positional fatty acid composition in camphor tree (Cinnamomum camphora) seed kernel oil (CKO) were analyzed, and for the first time, the effect of CKO on body fat deposition and blood lipids in rats was studied. The major fatty acids in CKO were determined to be decanoic acid (C10:0, 51.49%) and dodecanoic acid (C12:0, 40.08%), and uniformly distributed at Sn‐1, 3, and Sn‐2 positions in triglyceride (TG). Rats were randomly divided into control, CKO, lard, and soybean oil groups. At the end of the experiment, levels of blood lipids and the fats of abdomen in the rats were measured. The main organ were weighted and used for the histological examination. The results showed that body weight and fat deposition in CKO group were significantly lower than the lard and soybean groups. Moderate consumption of CKO was found to improve the levels of blood TG and low density lipoprotein cholesterol.     

不同物种茶油脂肪酸组成及其在Sn-2位上的分布

试验以十五烷酸为内标,定量分析9种不同物种茶油的脂肪酸组成;用胰脂肪酶专一性地水解茶油甘油三酯中Sn-1和Sn-3位上的脂肪酸,并经薄层层析分离出Sn-2位甘一酯,采用气相色谱仪对Sn-2位脂肪酸组成进行测定。结果表明:9个不同物种茶油主要由棕榈酸、硬脂酸、油酸、亚油酸、亚麻酸5种脂肪酸组成,浙江红花油茶的油酸和不饱和脂肪酸的含量最高,分别为82.79g/100g和84.77g/100g;且脂肪酸之间存在一定的相关性;Sn-2位上的脂肪酸主要为油酸和亚油酸,短柱茶在Sn-2位的油酸和不饱和脂肪酸含量最高,分别为82.96%,92.89%。表明茶油是一种不饱和脂肪酸含量高且容易被人体消化吸收的油脂。     

气相色谱法测定脂肪酸含量判定山茶油纯度

利用气相色谱法,对山茶油掺入大豆油、菜籽油、玉米油和葵花籽油的掺伪油进行脂肪酸组成分析。结果表明:油酸、亚油酸和亚麻酸可作为鉴别山茶油中掺伪大豆油和菜籽油的特征脂肪酸,棕榈酸、油酸和亚油酸可作为鉴别山茶油中掺伪玉米油和葵花籽油的特征脂肪酸;回归预测模型相关系数(R^2)较高(> 0. 99),可分别检出掺伪量4%的大豆油和菜籽油,掺伪量8%的玉米油和葵花籽油,回收率在96. 56%~112. 88%之间。该方法灵敏度高,定量准确,可为掺伪山茶油纯度鉴别及调和山茶油配比的定量分析提供科学依据。     

Fungal metabolism of butter and shea oils by Penicillium roquefortii in solid state cultures

Monoacylglycerols (monoglycerides, MAGs) were produced from butter oil and shea stearin fraction (shea oil) by two strains of Penicillium roquefortii, FRR 2456 (isolated from a spoilt melon) and Wisbey PJ (a commercial dairy strain), at pH 7.0 at 10 and 25 °C. The system was designed as a model of cheese using modified Czapek medium in solid state cultures. Shea oil with its unique fatty acid profile (stearic, oleic and palmitic acids) was used for comparison with butter oil. Yields of MAGs, which ranged from 3 to 14 g kg^?1 oil, were higher with butter than with shea oil and higher when the spoilage strain FRR 2456 was used. Monoacylglycerols produced by mycelium‐bound lipases from both fungal strains were mainly sn‐1(3) or α isomers (60–70 mol%). Monopalmitin was the major MAG produced from both butter and shea oils. The production and use of MAGs alone or in combination with free fatty acids (FFAs) as food preservatives are discussed. It is implied that sn‐1(3) MAGs together with free fatty acids may be part of a natural antimicrobial system in relatively high‐pH foods such as blue mould‐ripened cheese where growth of foodborne pathogens such as Listeria monocytogenes can be a problem. Copyright © 2003 Society of Chemical Industry     

Characterisation of fatty acids and bioactive compounds of kachnar (Bauhinia purpurea L.) seed oil

Information concerning the exact composition of kachnar (Bauhinia purpurea) seed oil is scare. In the present contribution, a combination of CC, GC, TLC and normal-phase HPLC were performed to analyse lipid classes, fatty acids and fat-soluble bioactives of kachnar seed oil. n-Hexane extract of kachnar oilseeds was found to be 17.5%. The amount of neutral lipids in the crude seed oil was the highest (ca. 99% of total lipids), followed by glycolipids and phospholipids, respectively. Linoleic, followed by palmitic, oleic and stearic, were the major fatty acids in the crude seed oil and its lipid classes. The ratio of unsaturated fatty acids to saturated fatty acid, was higher in neutral lipid classes than in the polar lipid fractions. The oil was characterised by a relatively high amount of phytosterols, wherein the sterol markers were β-sitosterol and stigmasterol. β-Tocopherol was the major tocopherol isomer with the rest being δ-tocopherol. In consideration of potential utilisation, detailed knowledge of the composition of kachnar (B. purpurea) seed oil is of major importance.     

Identification and quantitative determination of the lipids of Alocasia macrorrhiza tubers

The identity, composition and concentration of each of the major lipids found in Alocasia tubers were investigated using a combination of chromatographic procedures. On a weight to weight basis, the neutral lipids, glycolipids and phospholipids comprised 60.5, 19.0 and 20.5% respectively while the total extractable lipids accounted for 0.6% of the dry weight. In addition to the conventional lipid classes of tubers, the presence of tri- and tetragalactosyl diglycerides was confirmed. The predominant fatty acid in each lipid class was linoleic acid with palmitic, oleic and linolenic acids being the other ones. In general, a high degree of unsaturation (66%), similar for most tuber lipids, was established for the component fatty acids of Alocasia.     

Lipase-catalysed production of triacylglycerols enriched in pinolenic acid at the sn-2 position from pine nut oil

BACKGROUND: The purpose of this study was to produce triacylglycerols (TAGs) enriched in pinolenic acid (PLA) at the sn‐2 position using the principle of acyl migration, from the pine nut oil containing PLA esterified exclusively at the sn‐3 position. RESULTS: Two types of lipase‐catalysed reactions, i.e. redistribution and reesterification of fatty acids, were successively performed using seven commercially available lipases as biocatalysts. Of the lipases tested, Novozym 435 and Lipozyme TL IM were effective biocatalysts for positioning PLA at the sn‐2 location. These biocatalysts were selected for further evaluation of the effects of reaction parameters, such as temperature and water content on the migration of PLA residues to the sn‐2 position and TAG content. For both lipases, a significant decrease in TAG content was observed after the lipase‐catalysed redistribution of fatty acids for both lipases. The reduced TAG content could be enhanced up to approx. 92%, through lipase‐catalysed re‐esterification of the hydrolysed fatty acids under vacuum. CONCLUSION: TAG enriched in PLA at the sn‐2 position was synthesised from pine nut oil via lipase‐catalysed redistribution and re‐esterification of fatty acid residues using Lipozyme TL IM and Novozym 435 as biocatalysts. Copyright © 2011 Society of Chemical Industry     

Optimization of the refining process of camellia seed oil for edible purposes

Processing conditions during degumming, alkaline refining, bleaching, and deodorization of crude camellia seed oil were optimized to obtain high-quality edible camellia oil. Physicochemical properties of camellia oil were monitored during refining steps. RBD (refined, bleached, and deodorized) camellia oil obtained using optimized refining conditions fully satisfied Korean quality standards for edible oil. The iodine value of camellia oil was 84.2 mg I₂/100 g of oil. Camellia oil contained an exceptionally high level of oleic acid (83.1%), along with minor quantities of other fatty acids (8.9% palmitic acid, 4.8% linoleic acid). The total saponin content in crude oil was 437 ppm, as determined by gravimetric analysis. Most (99.8%) of the saponin in crude oil was removed during the refining process. The physicochemical properties of camellia oil were similar to olive oil. RBD camellia oil is virtually colorless and bland tasting and is suitable for edible purposes.     

CHEMICAL CHARACTERIZATION AND STEREOSPECIFIC ANALYSIS OF LIPIDS SYNTHESIZED BY CERTAIN YEAST STRAINS

Fatty acid analysis of lipids from yeast strains, Apiotrichum curvatum ATCC 10567, Cryptococcus albidus ATCC 56297, Lipomyces starkeyi ATCC 12659, and Rhodosporidium toruloides ATCC 10788, grown on whey permeate revealed palmitic, stearic, oleic and linoleic acids as the predominant fatty acids in the triacylglycerol fractions. The phospholipid fractions were dominated by oleic and linoleic acids. The stereospecific distribution of fatty acids in the triacylglycerol fractions of lipids from two yeast strains, Apiotrichum curvatum ATCC 10567 and Lipomyces starkeyi ATCC 12659, was determined and revealed the presence of almost entirely unsaturated fatty acids at the sn-2 position (91.9% and 82.8%, respectively). The dominance of unsaturated fatty acids (in the range of 61.5 to 72.3%) at the sn-1 position was also observed. Oleic acid was the predominant fatty acid at positions sn-1 and sn-2 for both yeast strains. Position sn-3 had the greatest concentrations of saturated fatty acids, with palmitic acid as the predominant fatty acid.     

松籽油脂肪酸组成及分布特征分析

通过气相色谱法分析了松仁油的总脂肪酸组成及其上位置分布特点。结果表明,松仁油主要含有亚油酸(46.29%)、油酸(26.68%)和松籽油酸(13.84%)。sn2位置上的亚油酸(66.84%)和油酸(28.33%)含量高于sn1,3上的含量,但是Δ5系列多不饱和脂肪酸(Δ5-PUFA)主要分布在sn1,3位置上。Δ5-PUFA的存在和它们选择性地分布在sn1,3位等特点是包括红松籽油在内主要松属植物果实油脂的特点。松籽油主要由12种甘油三酯组成,其中含量比较多的是LLPi(24.13%),OLL/LOL(17.87%)和LOPi(14.32%)。我们还对植物甾醇和维生素进行分析,结果显示松籽油含有141.64mg/100g的总植物甾醇和23.63mg/100g的总生育酚。     

Composition of meat and offal from weaned and fattened rabbits and results of stereospecific analysis of triacylglycerols and phosphatidylcholines

BACKGROUND: Rabbit meat has excellent nutritive properties. The purpose of this study was to characterize rabbit meat and offal; in particular, the lipid fraction was studied in order to evaluate total and positional fatty acid (FA) compositions of triacylglycerol (TAG) and phosphatidylcholine (PC) fractions. Eight samples of weaned and eight of fattened rabbits were considered. RESULTS: Fattened rabbit meat contained slightly higher protein percentage content (P < 0.05) in comparison to weaned (20.1% versus 18.0%). Calcium content was higher in meat than in offal, unlike sodium, iron, zinc, manganese and copper. The cholesterol content in offal was much higher than in meat. FA profiles of total lipid showed a high percentage of unsaturated fatty acids and an n‐6/n‐3 ratio of 10.3 for fattened rabbit meat. Stereospecific analysis of TAG and PC was carried out on an eight‐sample pool of each meat and offal from weaned and fattened rabbits. In all samples the sn‐2‐position was prevalently esterified with oleic and linoleic acids in TAG, with polyunsaturated fatty acids in PC. CONCLUSION: Lipids from rabbit meat presented higher content of monounsaturated FA and lower n‐6/n‐3 ratio in comparison to offal, which was characterized by higher cholesterol and mineral levels. Copyright © 2011 Society of Chemical Industry     

浸出与冷榨山茶油中脂肪酸的测定及品质评价

目的:进行两种不同提取方法的山茶油的含量和脂肪酸组成及其它相关理化指标的比较和分析。方法:运用脂肪酸标准品的气相色谱比对的方法分析浸出的山茶油与冷榨山茶油里面脂肪酸成分的组成及其含量,通过观察此两种不同提取方法山茶油的透明度、其颜色及光泽度,采用国家规定的标准的检测方法,对其皂化值、不皂化物、碘值、折光率、水分、易挥发性物质、不可溶性的杂质、过氧化值、酸值、相对密度等理化指标进行了详细的检测鉴别和分析。结果:浸出山茶油检出了14种脂肪酸,冷榨山茶油检出了12种脂肪酸,其中油酸(79.37%、80.55%)、棕榈酸(8.79%、8.81%)、亚油酸(7.49%、7.16%)为主要脂肪酸,及花生一烯酸等不饱和脂肪酸(0.02%、0.96%)与硬脂酸(2.11%、2.07%)等饱和脂肪酸;两种工艺山茶油理化指标符合质量指标要求,冷榨山茶油与浸出山茶油比较,体外抗氧化效果与体内抗疲劳效果差异没有统计学意义(p>0.05),浸出山茶油酸值和过氧化值高于冷榨山茶油,且差异有显著差异(p<0.05)。结论:本试验采用的冷榨山茶油与浸出山茶油均符合国家标准,从脂肪酸含量、理化指标、体外抗氧化试验与体内抗疲劳试验结果综合比较,冷榨山茶油品质略优于浸出山茶油。