Dihydrosterculic acid,a major fatty acid component ofEuphoria longana seed oil

The seed oil ofEuphoria longana, Sapindaceae, contains 17.4% of 9,10-methyleneoctadecanoic (dihydrosterculic) acid. This identification is based on information from thin layer chromatography, infrared analysis, gas liquid chromatography, nuclear magnetic resonance and mass spectroscopy. Since GLC of the oil showed components that emerged between the usual triglycerides, the cyclopropanoid acid is apparently a triglyceride constituent. The presence of smaller amounts, less than 1%, of cyclopropanoid fatty acids of different chain lengths is indicated by GLC and TLC analyses of the methyl esters. The other major fatty acids in this oil are: 16∶0 (19%), 18∶0 (7%), 18∶1 (36%), 18∶2 (6%), 18∶3 (5%) and 20∶0 (4%).Euphoria oil contains considerably larger amounts of cyclopropanoid fatty acids than previously reported in other seed oils. Presented at the AOCS-AACC Joint Meeting, Washington, D.C., April 1968. No. Utiliz. Res. Dev. Div.; ARS, USDA.     

Effects of dietary marine oils and olive oil on fatty acid composition, platelet membrane fluidity, platelet responses, and serum lipids in healthy humans

The influence of various dietary marine oils and olive oil on fatty acid composition of serum and platelets and effects on platelets and serum lipids were investigated as part of an extensive study of the effects of these oils on parameters associated with cardiovascular/thrombotic diseases. Healthy volunteers (266) consumed 15 mL/d of cod liver oil (CLO); whale blubber oil (refined or unrefined); mixtures of seal blubber oil and CLO; or olive oil/CLO for 12 wk. In the CLO, seal oil/CLO, and whale oil groups, serum levels of eicosapentaenoic acid (EPA) were increased. In platelets, EPA was increased in the CLO, seal/CLO, and olive oil/CLO groups. The localization of n-3 polyunsaturated fatty acids in the triacylglycerols did not seem to influence their absorption. Intake of oleic acid is poorly reflected in serum and platelets. No significant differences in triacylglycerols (IG), total cholesterol, or high density lipoprotein cholesterol were observed, even though TG were reduced in the CLO, CLO/seal oil, and whale oil groups. Mean platelet volume increased significantly in both whale oil groups and the CLO/olive oil group. Platelet count was significantly reduced in the refined whale oil group only. Lipopolysaccharide-stimulated blood tended to generate less thromboxane B₂ in CLO, CLO/seal, and CLO/olive groups. The whale oils tended to reduce in vivo release of β-thromboglobulin. In conclusion, intake of various marine oils causes changes in platelet membranes that are favorably antithrombotic. The combination of CLO and olive oil may produce better effects than these oils given separately. The changes in platelet function are directly associated with alterations of fatty acid composition in platelet membranes.     

Distinctive medium chain wax esters,triglycerides, and diacyl glyceryl ethers in the head fats of the pacific beaked whale,Berardius bairdi

Lipids were extracted from the mandibular fat body (jaw), the fatty forehead (melon), and the dorsal blubber of a Pacific beaked whale (Berardius bairdi) and separated into lipid classes by preparative thin layer chromatography. The head fats were mixtures of wax esters and triglycerides with a very small amount of diacyl glyceryl ether. The blubber fat contained 97% was ester and 3% triglyceride. Gas liquid chromatography (GLC) of the intact lipid classes indicated an unusually low C₂₆–C₃₀ range for most of the jaw and melon wax esters compared to the more normal C₃₂–C₄₀ molecules found in the blubber. Distinctive lower molecular weight C₂₄–C₄₀ triglycerides occurred in the head fats vs. the usual C₄₄–C₅₈ range in the blubber. Most diacyl glyceryl ethers were in the C₃₅–C₄₆ range, below the molecular weight of hexadecyldipalmitoyl glyceryl ether (C₄₈). GLC of the derived fatty acid methyl esters showed that the lower molecular weight neutral lipids in the head fats were due to high levels of iso-10∶0, n−10∶0, iso-11∶0, iso-12∶0, n−12∶0, and iso-13∶0 acids. The wax ester fatty alcohols and the alkoxy chains of the glyceryl ethers were mostly the C₁₄–C₂₀ chain lengths commonly observed in marine organisms. The distinctive medium chain neutral lipids in the jaw and melon fats of this whale may be related to the postulated acoustical role of these tissues in echolocation.     

The fatty acid composition of edible marine fish oils

The body oils of 13 species of marine edible fishes found around the Karachi-Makran coast were studied by gas-liquid chromatography (GLC) for their fatty acid composition. The analyses showed the presence of fatty acids with chain lengths from 10 to 24 carbon atoms and with zero to six double bonds. The oils were found to be rich in polyunsaturated acids, particularly the penta- and hexaenoic. Certain major fatty acids were found to vary widely among the species: myristic acid 2.3 to 13.7%; palmitic 11.6 to 41.2%; stearich 7.2 to 23.2%; oleic 6.9 to 29.6%; eicosapentaenoic 1.4 to 19.0%; docosapentaenoic zero to 10.2%; and docosahexaenoic zero to 36.4%. The linoleic and linolenic acids were present in small amounts in some of the fish oils, and arachidonic acid was present in all of them.     

Unsaturated C18 α-hydroxy acids inSalvia nilotica

The oil ofSalvia nilotica Jacq. (Labiatae) seed contains 0.6% α-hydroxyoleic, 4.2% α-hydroxylinoleic, and 5.4% α-hydroxylinolenic acids. The first two have not been found previously in seed oils. In addition to the common fatty acids, also identified were small amounts of three unsaturated C₁₇ acids and one branched chain C₁₇ acid. Methyl esters of the component fatty acids were fractionated by both column and thin-layer chromatography. These esters were identified by combination of gas chromatography, GC-mass spectrometry, ozonolysis-GC, infrared, and nuclear magnetic resonance.     

Skin surface lipids of the dog

The skin surface lipid of the dog has been reported to contain a high proportion of diol diesters having a lower mobility on thin layer chromatography than diesters from other species in spite of containing similar fatty acid and diol components. In the present study, dog skin surface lipid was separated by preparative thin layer chromatography into sterol esters (42%), wax diesters (32%), free sterols (9%), polar lipids (7%), and unidentified components (10%). The diesters contained 1,2-diols, each esterified with one long chain fatty acid and one isovaleric acid moiety. The diols were principally branched chain C₂₁ and C₂₂ compounds while the long chain fatty acids esterified with them were mainly C₂₀ and C₂₁ branched compounds. The fatty acids from the sterol esters were mostly saturated, branched chain C₁₉ to C₂₃, together with 7% of straight chain monoenoic acids, principally C₂₁ and C₂₂. There were only trace amounts of free sterols other than cholesterol, while the esterified sterols contained 96% cholesterol and 4% lathosterol.     

Lipids of freshwater dolphinSotalia fluviatilis: Comparison of odontocete bioacoustic lipids and habitat

The melon and jaw lipids of the freshwater dolphinSotalia fluviatilis are composed mainly of isovaleroyl wax esters and diisovaleroyl triglycerides. The blubber fat contains only a trace of wax ester and is mostly tri- (long chain) and monoisovaleroyl triglycerides. Detailed gas liquid chromatographic analyses of the intact wax esters and triglycerides and of the derived fatty acids and fatty alcohols indicate common compositional patterns in the wax esters and triglycerides of the respective head lipids. Both odd and even long chain (C₁₂−C₁₆) iso-structures are prominent in the melon and jaw lipids, but only higher odd chain length iso-acids are major components in the blubber.Sotalia fluviatilis (family Delphinidae) andInia geoffrensis (family Platanistidae) share the same freshwater habitat in the upper Amazon River, and both utilize echolocation to navigate and to find food. Comparison of their respective bioacoustical lipid compositions shows distinctive types of head fats,Sotalia being rich in iso-5∶0 andIndia lacking iso-5∶0. This indicates that isovaleric acid per se has no obligatory role in dolphin echolocation.     

Linolenic Acid as the Main Source of Acrolein Formed During Heating of Vegetable Oils

Acrolein, which is an irritating and off-flavor compound formed during heating of vegetable oils, was estimated by the gas–liquid chromatography (GLC). Several vegetable oils such as high-oleic sunflower, perilla, rapeseed, rice bran, and soybean oils were heated at 180 °C for 480 min and then the concentration of acrolein in the head space gas was determined by GLC. The formation of acrolein was greatest in perilla oil among the tested oils, while it was much lower in rice bran oil and high-oleic sunflower oil. There was a good correlation between the level of acrolein and linolenate (18:3n-3) in the vegetable oils. To investigate the formation of acrolein from linolenate, methyl oleate, methyl linoleate, and methyl linolenate were also heated at 180 °C, and the amounts of acrolein formed from them were determined by GLC. The level of acrolein was the greatest in methyl linolenate. Acrolein was also formed from methyl linoleate, but not from methyl oleate. Acrolein in vegetable oils may be formed from polyunsaturated fatty acids, especially linolenic acid but not from glycerol backbone in triacylglycerols.     

Cyclopropenoid Fatty Acids of Sida grewioides and Hibiscus caesius (Malvaceae) Seed Oils

Evidence is provided that sterculic and malvalic acids occur together in seed oils of Sida grewioides and Hibiscus caesius. Sida grewioides oil contains 1.3% sterculic and 2.1 % malvalic acids; Hibiscus caesius oil contains 1.0 % sterculic and 5.7 % malvalic acids. The cyclopropenoid acids were characterised by gas liquid chromatography (GLC) of the silver nitrate-methanol treated methyl esters using Sterculia foetida esters as a reference standard. A third unusual component, identified as epoxy acid, also occurs in Sida grewioides oil as a trace constituent.     

Fractional vacuum distillation of herring oil methyl esters

Methyl esters of a Canadian Atlantic herring oil containing 62% monoethylenic fatty acids were subjected to batch fractional distillation under vacuum on a pilot plant scale, to study the feasibility of fractionating fatty acid esters of marine oils of low iodine value into monounsaturated fractions with increased commercial value for industrial chemical uses. A total of 64 methyl ester fractions were collected and analyzed by gas liquid chromatography. Recoveries of the major saturated and monounsaturated acids were close to 100%, and some fractions contained over 90% of the desired 22:1 long chain monounsaturated acids. The short chain polyunsaturated acids were recovered in good yields, but the long chain highly unsaturated acids were recovered in yields of 60% or less due to oxidative and thermal decomposition in the particular apparatus employed. If small amounts of unsaturated acids are acceptable, fractional distillation of low iodine value marine oils could inexpensively supply fractions with high concentrations of methyl esters of longer chain (C₂₀ and C₂₂) monounsaturated and shorter chain (C₁₄) saturated acid or (C₁₆) saturated-monounsaturated acid mixture.     

Solvent-free enzymatic glycerolysis of marine oils

Marine triglyceride oils (cod liver oil and oils from blubber of harp seal and minke whale) were reacted with glycerol using lipase as a catalyst at low temperature. A solvent-free batch system with magnetic stirring was used. Solidification of the reaction mixture occurred, and a mixture of mono-, di-, and triglycerides was obtained in all cases. The recovered glyceride mixtures were solid at room temperature. The yield of monoglyceride (MG) and the fatty acid profile of the MG fractions were dependent on oil and the type of lipase used as a catalyst. Of the commercially-available lipases investigated, lipase AK fromPseudomonas sp. synthesized the highest yield of MG (42–53%) at 5°C. These MG fractions were low in saturated fatty acids (4–11%) and high in long-chain monounsaturated fatty acids (52–69%). The concentration of n-3 polyunsaturated fatty acids was 12–20%.     

Chemical evaluation of egyptian citrus seeds as potential sources of vegetable oils

Seeds of the citrus fruits orange, mandarin, lime and grapefruit were analyzed. Petroleum ether-extracted oils of such seeds amounted to more than 40% of each. Physical and chemical properties of the extracted oils are presented. Samples of the extracted oils were saponified and the unsaponifiables and fatty acid fractions isolated. The isolated unsaponifiables and fatty acids were analyzed by GLC. GLC analysis of the unsaponifiables revealed compositional patterns differ-ent in number, type and relative concentration of fractions according to type of citrus seed oil, depending on the solvent system used for oil extraction and unsaponifiable matter isolation. The compositional patterns of the unsaponifiables were similar to that of cottonseed oil. Mandarin and grapefruit oils are free of cholesterol. The data demonstrate that the fatty acid compositional patterns of the oils differ; Mandarin seed oil contains the largest number of fatty acids, and grapefruit seed oil contains the lowest. The total amounts of volatile fatty acids in these oils are generally higher than those of other edible oils. Lime seed oil is similar, in the degree of unsaturation, to soybean oil. The orange oil pattern is similar to cottonseed oil. The amount of total essential fatty acids in lime seed oil is the highest of the oils studied.     

环氧油脂肪酸组成分析研究

通过薄层色谱、气相色谱、色质联用等技术,首次得到了油脂环氧化反应期间的脂肪酸环氧化反应规律:开始反应阶段,高含量不饱和脂肪酸反应速率高于低含量不饱和脂肪酸;环氧化反应期间,多不饱和脂肪酸首先生成单环氧酸,之后再逐渐生成二环氧酸,最后生成三环氧酸;富含亚麻酸的油脂环氧化反应时有更易于开环反应的趋向,其次是富含亚油酸的油脂,再次是富含油酸的油脂.实验结果表明,不同环氧油原料在进行环氧化反应时需要控制不同的反应条件,以避免开环副产物量的增加,从而制备得优质环氧油产品.     

Composition of fatty acids and structure of triglycerides in medium and low erucic acid rapeseed

Total triglycerides in medium (MEAR) and low (LEAR) erucic acid cultivars of rapeseed were fractionated by argentation chromatography into twelve and ten fractions, respectively. Gas liquid chromatography of the fatty acids in the triglyceride fractions and their 2-monoglycerides was used to evaluate the structural characteristics of the individual fractions. Fractionation occurred on the basis of degree of unsaturation, molecular weight and positional characteristics. The most mobile fractions contained 34–50% of saturated fatty acids while the less mobile had 59–65% of polyunsaturated fatty acids. In the medium erucic acid oil, long chain fatty acids (C20–C22) were found in all fractions, but four fractions of low erucic acid oil were essentially free of long chain acids. Two of these fractions in the latter oil, which represented 44% of the total triglycerides, were glycerol trioleate and dioleoyllinoleoylglycerol. The majority of the 2-positions were occupied by unsaturated C18 fatty acids, generally in the order of linoleic ≥linolenic> oleic acids. The saturated and long chain fatty acids occurred predominantly in the 1-and 3-positions. The various fractions of medium and low erucic acid oils were similar in structural composition except that eicosenoic and erucic acids substituted for oleic acid in some external positions. Erucic acid did not appear to substitute directly for oleic acid in the 2-position.     

Analysis of conjugated octadecatrienoic acids inmomordica balsamina seed oil by GLC and13C NMR Spectroscopy

Separation of conjugated octadecatrienoic acids by open tubular gas liquid chromatography (GLC) was performed using glass capillary columns coated with Carbowax 20 M and with OV-1. The equivalent chain length of geometrical isomers of the conjugated octadecatrienoic acids belonging to the two series C_18:3Δ^8.10.12 and C_18:3Δ^9.11.13 were determined. The application of these results to the study of theMomordica balsamina seed oil shows that this oil contains two conjugated octadecatrienoic fatty acids in appreciable amounts, punicic acid (50%) and α-eleostearic acid (13%). The isomerization of conjugated acids inM. balsamina seed oil was followed for one year. Quantitation of octadecatrienoic acids using GLC gave results similar to those obtained with¹³C NMR.     

Regioselective analysis of triacylglycerols by lipase hydrolysis

A modified procedure for the regiospecific analysis of triacylglycerols (TAG) with a 1,3-specific lipase is described. After partial lipase hydrolysis of the triacylglycerol, the released free fatty acids (FFA) and 1,2(2,3)-diacylglycerols (DAG) were isolated by thin-layer chromatography (TLC) and converted to fatty acid methyl esters (FAME). The FAME were analyzed by gas-liquid chromatography (GLC). The 1,3-specific lipases used in this study included supported preparations from strains ofMucor miehei andRhizopus oryzae. The method also was applied to the regiospecific analyses of tung nut and Chinese melon seed oil triacyglycerols, both of which contain high proportions of α-elaeostearic acid. The TAG composition of the oils was substantiated in parallel analysis of the oils by highperformance liquid chromatography with chemical ionization mass spectrometric detection of intact TAG.     

Minor component fatty acids of common vegetable oils

A combination of gas-liquid chromatography (GLC) and oxidative cleavage on fractions isolated by mercury derivative chromatography has shown the presence of previously unreported minor component fatty acids in olive, soybean, cottonseed, corn, peanut, rapeseed and safflower oil. All of the oils examined contain small amt of saturated acids above arachidic, some as high as hexacosanoic acid.Cis-11-octadecenoic acid was found in amt ranging from 0.5~2.0%.Cis-11-eicosenoic acid is present in the 0.04~1.4% range (rapeseed oil excluded). The tetracosenoic acid present in rapeseed (0.4%) and safflower oil (0.1%) has been identified as thecis-15-tetracosenoic acid. No unusual polyenoic species were detected with the exception of those in rapeseed oil, which contains 0.6% of both 11,14-eicosadienoic and 13,16-docosadienoic acid.     

Precision of low trans fatty acid level determination in refined oils. Results of a collaborative capillary gas-liquid chromatography study

The results of a collaborative study by 38 laboratories were analyzed statistically to calculate the precision of a novel capillary gas-liquid chromatography (GLC) method for the determination of low levels of trans fatty acids (TFA) in edible oils. The participants came from 17 countries, mainly European, and were spread evenly between Unilever companies and external laboratories. All participants used the same GLC method, including a temperature optimization step, which is suitable for the determination of a large range of TFA levels in refined oils and fats and for the determination of total saturated fatty acid, cis mono- and cis-cis methylene-interrupted polyunsaturated fatty acid isomers. For TFA levels down to 0.5%, the collaborative study yielded values for R_within that ranged from 0.08 to 0.13% (absolute values) and for R_between from 0.2 to 0.4%, depending on the isomer distribution in a particular edible oil. The proposed GLC method allows reliable TFA analysis at low levels that is suitable for monitoring oil processing practices and intake control.     

Search for new industrial oils: XVI. Umbelliflorae—seed oils rich in petroselinic acid

Seed oils of the order Umbelliflorae, including those from the families Umbelliferae, Garryaceae, Araliaceae, Cornaceae, Davidiaceae, Nyssaceae and Alangiaceae, were analyzed for fatty acid composition by gas liquid chromatography (GLC) of their methyl esters. The characteristic fatty acid of the order, petroselinic acid, occurred in the Umbelliferae in amounts up to 85%. In the Araliaceae, the content was as high as 83% and in the Garryaceae as high as 81%. The other major acids were palmitic, oleic and linoleic acids, with small amounts of hexadecenoic, stearic, linolenic, and, in some cases, C₂₀ acids. petroselinic acid was determined by microscale ozonolysis of the C₁₈ monoenoic esters and subsequent GLC of the ozonolysis products. The occurrence of high oil contents (up to 46%) combined with exceptionally high (up to 83%) single component purity is notable and emphasizes the potential of the Umbelliflorae as a raw material source for the chemical industry.     

Detection of adulteration of olive oil by argentation thin layer chromatography

Minute amounts of adulterant seed oils in olive oil can be detected by GLC analysis of fatty acids of the polyunsaturated triglyceride fraction, obtained by TLC on silver nitrate impregnated silica gel. Every possible effort was made to avoid any critical or time consuming manipulation in this method in order to develop it as a routine testing procedure. A complete analysis is possible in less than 2 hr and the detection of as low as 2% adulteration by other seed oils is accurate and reliable.