Varietal difference in lipid content and fatty acid composition of highbush blueberries

Lipids from five cultivars of highbush blueberries (Vaccinium corymbosum L.) were extracted and fractionated into neutral lipids (60–66%), glycolipids (20–22%) and phospholipids (14–18%). The major fatty acids in all fractions were palmitic (16∶0), oleic (18∶1), linoleic (18∶2), and linolenic (18∶3) acids. All lipid classes had a large concentration of C₁₈ polyunsaturated acids (84–92%), indicating that blueberries are a rich source of linoleic and linolenic acids. Changes in the fatty acid composition of neutral lipids and phospholipids were not significantly different among the five cultivars, but significant differences were noted in the ratios of linoleic and linolenic acids in the glycolipids fraction.     

Application of urea complexes in the purification of fatty acids,esters, and alcohols. III. Concentrates of natural linoleic and linolenic acids

Summary Concentrates of natural linoleic acid (linoleic acid content, 85–95%) have been prepared in 50–72% yields from corn oil fatty acids by preferential precipitation of the saturated and monounsaturated fatty acids at room temperature as their urea complexes. By a similar procedure, concentrates of natural linolenic acid (linolenic acid content, 87–89%) have been prepared in 55–61% yields from perilla oil fatty acids by preferential precipitation of the saturated, monounsaturated, and diunsaturated fatty acids. Although concentrates of natural linolenic acid containing only 66–70% linolenic acid were obtained from linseed oil fatty acids, yields were 87–90%. A levelling-off effect has been observed in the use of the preferential precipitation technique in raising the purity of concentrates of linoleic and linolenic acid. This parallels the experience in the purification of these acids by low-temperature crystallization. The preceding papers in this series are references 12 and 13. Presented at the Fall Meeting of the American Oil Chemists' Society, Cincinnati, O., Oct. 20–22, 1952. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S. Department of Agriculture.     

The lipids of the common house cricket,Acheta domesticus L. I. Lipid classes and fatty acid distribution

The lipids of the common house cricket,Acheta domesticus L., have been examined with the following results. The fatty acids associated with the lipid extracts do not change significantly from the third through the eleventh week of the crickets' postembryonic life. The major fatty acids are linoleic (30–40%), oleic (23–27%), palmitic (24–30%), and stearic acids (7–11%). There are smaller amounts of palmitoleic (3–4%), myristic (∼1%), and linolenic acids (<1%). The fatty acid composition of the cricket lipids reflects but is not identical to the fatty acids of the dietary lipids: linoleic (53%), oleic (24%), palmitic (15%), stearic (3%), myristic (2%), and linolenic acid (2%). The amount of triglycerides present in the crickets increases steadily from the second through the seventh or eighth week of postembryonic life, then drops sharply. Other lipid classes, such as hydrocarbons, simple esters, diglycerides, monoglycerides, sterols, and free fatty acids remain about constant. The composition of the fatty acids associated with the tri-, di-, and monoglycerides and the free fatty acid fraction are all about the same. The fatty acids associated with the simple esters are high in stearic acid. Postdoctoral Research Associate, Department of Chemistry, University of Michigan, 1965–1967.     

Fatty acid composition of Iranian citrus seed oils

Fatty acid compositions of seed oils from eight Iranian citrus fruits were determined. The ranges of values for major fatty acids were 21.8–29.4% palmitic, 3.1–7.60% stearic, 0.3–1.3% palmitoleic, 23.5–32.3% oleic, 33.5–39.8% linoleic, and 3.1–7.6% linolenic. Low amounts (up to 0.1%) of myristic and arachidic acids and traces of a few unidentified ones constituted minor fatty acids.     

Characterization of polar and nonpolar seed lipid classes from highly saturated fatty acid sunflower mutants

The seed lipids from five sunflower mutants, two with high palmitic acid contents, one of them in high oleic background, and three with high stearic acid contents, have been characterized. All lipid classes of these mutant seeds have increased saturated fatty acid content although triacylglycerols had the highest levels. The increase in saturated fatty acids was mainly at the expense of oleic acid while linoleic acid levels remained unchanged. No difference between mutants and standard sunflower lines used as controls was found in minor fatty acids: linolenic, arachidic, and behenic. In the high-palmitic mutants palmitoleic acid (16∶1n−7) and some palmitolinoleic acid (16∶2n−7, 16∶2n−4) also appeared. Phosphatidylinositol, the lipid with the highest palmitic acid content in controls, also had the highest content of palmitic or stearic acids, depending on the mutant type, suggesting that saturated fatty acids are needed for its physiological function. Positional analysis showed that mutant oils have very low content of saturated fatty acids in the sn-2 position of triacylglycerols, between the content of olive oil and cocoa butter.     

Fatty acid composition of seed oil triglycerides inCoincya (Brassicaceae)

Oil and triglyceride contents and fatty acid composition were determined for seeds in nine taxa belonging to the genusCoincya (Brassicaceae) on the Iberian Peninsula (Spain and Portugal). The oil content ranges from 11.1 to 24.6%, triglycerides from 68.7 to 88.5%. The major fatty acids were erucic (24.6–30.5%), linolenic (17.7–27.7%), linoleic (13.9–24.6%) and oleic acid (12.3–21.8%).     

Determination of the fatty acid composition of the oil in intact-seed mustard by near-infrared reflectance spectroscopy

Near-infrared reflectance spectroscopy (NIRS) was used to estimate the fatty acid composition of the oil in intact-seed samples of Ethiopian mustard (Brassica carinata Braun) within a mutation breeding program that produced seeds with variable fatty acid compositions. Five populations, from 1992 to 1996 crops, were included in this study; and NIRS calibration equations for major fatty acids (palmitic, stearic, oleic, linoleic, linolenic, eicosenoic, and erucic) were developed within each single population. Furthermore, global calibration equations, including samples from the five populations, were developed. After external validation, the NIRS technique permitted us to obtain a reliable and accurate nondestructive estimation of the fatty acid composition of the oil, especially for the major acids—oleic, linoleic, linolenic, and erucic. For these, the r ² in external validation was higher than 0.95 by using both single-and multipopulation equations, and higher than 0.85 for the remaining fatty acids. Moreover, the multipopulation equations provided an accurate estimation of samples from a population not represented in the calibration data set, with values of coefficient of determination in validation (r ²) from 0.80 (palmitic and eicosenoic acids) to 0.97 (erucic acid). The ability of NIRS to discriminate among different fatty acid profiles was mainly due to changes within six spectral regions, 1140–1240, 1350–1400, 1650–1800, 1880–1920, 2140–2200, and 2240–2380 nm, all of them associated with fatty acid absorbers. Thus, NIRS can be used to estimate the fatty acid composition of Ethiopian mustard seeds with a high degree of accuracy, provided that calibration equations be developed from calibration sets that include large variability for the fatty acid composition of the oil.     

Oil content and fatty acid composition of chia (Salvia hispanica L.) from five northwestern locations in Argentina

Any new crop for which there is a market, and which appears to be adapted to the region, would be attractive to replace nonprofitable traditional crops in Northwestern Argentina. Chia (Salvia hispanica L.) is especially attractive because it can be grown to produce oil for both food and industry. The fatty acids of chia oil are highly unsaturated, with their main components being linoleic (17–26%) and linolenic (50–57%) acids. Seeds from a chia population harvested in Catamarca were sown in five Northwestern Argentina locations. The oil from the chia seeds produced under these five field conditions was measured. Linolenic, linoleic, oleic, palmitic, and stearic fatty acid contents of the oil were determined by gas chromatographic analysis. The results showed variations in oil content, and the oleic, linoleic, and linolenic fatty acid concentrations of the oil were significantly affected by location.     

Soybean seed composition under high day and night growth temperatures

High diurnal temperatures often affect development of soybean [Glycine max (L.) Merr.], but little is known about the relative influence of high day and night temperatures on the chemical composition of the seed. This study was conducted to determine the effects of combinations of high day and night temperatures during flowering and pod set (R1–R5), seed fill and maturation (R5–R8), and continuously during the reproductive period (R1–R8) on soybean seed oil, protein, and fatty acid composition. Day/night temperatures of 30/20, 30/30, 35/20, and 35/30°C were imposed on the soybean cultivar Gnome 85 in growth chambers. The day/night temperature combinations during R1–R5 had little effect on the oil and protein concentration and the fatty acid composition of seed produced. As mean daily temperature increased from 25 (30/20) to 33 (35/30)°C during R5–R8 and 25 (30/20) to 33 (35/30)°C during R1–R8, and oil concentration decreased and protein concentration increased. Increased day temperature during R5–R8 and R1–R8, averaged across the two night temperatures, increased oleic acid and decreased linoleic and linolenic acids. When night temperature was increased at 30°C day temperature during R5–R8 and R1–R8, oleic acid decreased and linoleic acid increased. When night temperature was increased at 35°C day temperature during R1–R8, oleic acid increased, and linoleic and linolenic acids decreased. These results indicate the importance of high day and night temperatures during seed fill and maturation in the oil, protein, and fatty acid composition of soybean seed.     

Influence of diet on (n−3) and (n−6) fatty acids in monkey erythrocytes

Cynomolgus monkeys were fed oils high in linoleic acid or with half of the linoleic acid replaced by either (n−3) linolenic acid or marine fatty acids. When the diet contained similar quantities of linoleic and (n−3) linolenic acid, erythrocyte fatty acids maintained a ratio of (n−6) to (n−3) fatty acids of approximately 2∶4. Fatty acids from menhaden oil enhanced the incorporation of eicosapentaenoic and docosahexaenoic acids into the monkey erythrocytes, the composition of which was not altered by additional α-tocopherol.     

Variation in Fatty Acid Composition in Indian Germplasm of Sesame

A germplasm collection of 33 entries comprising 22 sesame (Sesamum indicum L.) cultivars, 4 landraces of S. mulayanum and 7 other accessions of 4 wild species were analyzed for the fatty acid compositions of their seed oil. The entries varied widely in their fatty acid compositions. The percentage content of oleic, linoleic, palmitic and erucic acids ranged between 36.7–52.4, 30.4–51.6, 9.1–14.8 and 0.0–8.0, respectively. Linolenic and arachidonic acids were the minor constituents but varied widely in wild species. Oleic and linoleic were the major fatty acids with mean values of 45.9 and 40.5%, respectively and the mean of their combined values was 86.4%. The polyunsaturated fatty acid (PUFA) compositions ranged from 30.9 to 52.5% showing high variation in PUFA in the germplasm. Linoleic acid content was very high in one landrace (47.8) and one accession each of three wild species, S. mulayanum (49.3), S. malabaricum (48.2) and S. radiatum (51.6%). Use of fatty acid ratios to estimate the efficiency of biosynthetic pathways resulted in high oleic and low linoleic desaturation ratios and consequently high linoleic and very low linolenic acid contents in seed oil. The results of this study provided useful background information on the germplasm and also identified a few accessions having high linoleic acid which can be used for developing cultivars with desirable fatty acid compositions.     

Positional distribution of fatty acids in cardiolipin of mitochondria from 21-day-old rats

Pure cardiolipins (1,3-diphosphatidylglycerol) were prepared from mitochondria of heart, liver and kidney from 21-day-old male Wistar rats and submitted toNaja naja venom phospholipase A₂ (EC 3.1.1.4) action. Incubation conditions were controlled carefully, and a complete hydrolysis of cardiolipin to lysocardiolipin {di [1 (1″) acylsn-glycero-3-phosphoryl] 1′, 3′-sn-glycerol} and fatty acids from positions 2 (2″) was obtained in less than two hr practically without side reactions. Cardiolipins from the three organs contained low levels of saturated fatty acids; stearic acid accounted for 0.4–0.7% and palmitic acid for 1.4–3.5% of total fatty acids. These percentages apparently depended on the organ. In all three cases, linoleic acid was the major component, but its percentage varied from 62–78% of total fatty acids. Acyl chains linked to positions 1 (1″) of all three cardiolipin preparations exhibited a similar pattern; they were composed of linoleic acid for 85–89%. This fatty acid also was the main component esterified at position 2 (2″), but its percentage was much more variable: from 39.8% in heart to 51.2% in kidney and 67.8% in liver mitochondria. The remaining acids comprised octadecenoic and polyunsaturated fatty acids with more than 18 carbon atoms in different proportions. As opposed to other phospholipids,cis-vaccenic acid, and not oleic acid, was the main octadecenoic acid present in cardiolipins. Octadecenoic acids were nine- to 10-fold more concentrated at positions 2 (2″) than at positions 1 (1″). The percentage ofcis-vaccenic acid was four- to five-fold higher than that of oleic acid at positions 2 (2″), whereas oleic acid dominated at positions 1 (1″). From results presented in this study and selected literature data, it may be concluded that fatty acids are asymmetrically distributed in cardiolipins of different origins, with linoleic acid showing a definite preference for position 1 (1″).     

Distribution of fatty acids during germination of soybean seeds

Gas chromatographic determination of the fatty acids in the seeds of soybean (Glycine max) showed mainly linoleic, oleic and palmitic acids with linoleic acid being the major component. Changes in the distribution of fatty acids were measured during germination in the cotyledons and roots. A decrease in palmitic and oleic acids was observed in the cotyledons from 6 to 12 days, while linoleic acid increased during the same period. In roots also, the major fatty acid was linoleic acid, while palmitic and linolenic acids were higher in roots in comparison with the cotyledons. During the 3–12 days of germination period, no major changes in the distribution pattern of fatty acids were observed in the roots. The possible significance of these changes is discussed.     

Incorporation of n−3 fatty acids of fish oil into tissue and serum lipids of ruminants

This study examines the biohydrogenation and utilization of the C₂₀ and C₂₂ polyenoic fatty acids in ruminants. Eicosapentaenoic (20∶5n−3) and docosahexaenoic (22∶6n−3) acids were not biohydrogenated to any significant extent by rumen microorganisms, whereas C₁₈ polyenoic fatty acids were extensively hydrogenated. The feeding of protected fish oil increased the proportion of 20∶5 from 1% to 13–18% and 22∶6 from 2% to 7–9% in serum lipids and there were reductions in the proportion of stearic (18∶0) and linoleic (18∶2) acids. The proportion of 20∶5 in muscle phospholipids (PL) increased from 1.5% to 14.7% and 22∶6 from 1.0% to 4.2%; these acids were not incorporated into muscle or adipose tissue triacylglycerols (TAG). In the total PL of muscle, the incorporated 20∶5 and 22∶6 substituted primarily for oleic (18∶1) and/or linoleic (18∶2) acid, and there was no consistent change in the porportion of arachidonic (20∶4) acid.     

The content and composition of sterols and sterol esters in low erucic acid rapeseed (Brassica napus)

The low temperature crystallization technique for the enrichment of “minor” components, such as sterols and sterol esters, from vegetable oils was applied to low erucic acid rapeseed oils. The recovery of free sterols and sterol esters was estimated by use of¹⁴C-cholesterol and¹⁴C-cholesterol oleate. 80% of the free sterols and 45% of the sterol esters were recovered in the liquid fraction, while in two studies total recoveries were 95% and 99%, respectively. This technique showed some selectivity toward the sterol bound fatty acids when compared to direct preparative thin layer chromatography (TLC) of the crude oil. Gas liquid chromatography (GLC) analysis of the free and esterified sterols as TMS-derivatives showed very little selectivity in the enrichment procedure. The fatty acid patterns of the sterol esters demonstrated, however, a preference in the liquid fraction for those sterol esters which have a high linoleic and linolenic acid content. The content of free sterols was 0.3–0.4% and that of sterol esters 0.7–1.2% of the rapeseed oils in both winter and summer types of low erucic acid rapeseed (Brassica napus) when the lipid classes were isolated by direct preparative TLC of the oils. The free sterols in the seven cultivars or breeding lines analyzed were composed of 44–55% sitosterol, 27–36% campesterol, 17–21% brassicasterol, and a trace of cholesterol. The esterified sterols were 47–57% sitosterol, 36–44% campesterol, 6–9% brassicasterol, and traces of cholesterol and Δ5-avenasterol. The fatty acid patterns of these esters were characterized by ca. 30% oleic acid and ca. 50% linoleic acid, whereas these acids constitute 60% and 20%, respectively, of the total fatty acids in the oil. Little or no variation in sterol and sterol ester patterns with locality within Sweden was observed for the one cultivar of summer rapeseed investigated by the low temperature crystallization technique.     

Quantitative analysis of fatty acids and sterols in Malagasy rice bran oils

The fatty acid and sterol compositions of six Malagasy rice bran oils were evaluated. Investigation by gas liquid chromatography (GLC) using Carbowax 20 M revealed 10 fatty acids, mainly palmitic (16–20%) oleic (41–44%) and linolenic (31–37%) acids. An OV 17 column was used to separate eight sterols, mainly Β-sitosterol (53–59%), campesterol (16–26%) and stigmasterol (10–13%). No significant variation for the fatty acid and sterol contents was observed among the rice varieties studied.     

Fatty acid composition and its relationship with physicochemical properties of pecan (Carya illinoensis) oil

The composition and physicochemical properties of pecan (Carya illinoensis) kernels and oils from different native trees of the central region of Mexico were investigated. The main compositional characteristic of the kernel was the high lipid content (70–79% w/w on dry basis) with elevated concentration of oleic acid (55–75% w/w). The results confirmed the relationship in the biosynthesis of linoleic and linolenic acids from oleic acid existing in oilseeds. Our results indicate that in pecans such relationship is a function of pecan tree age. The proportion of oleic, linoleic, and linolenic fatty acids determined the oxidative stability, viscosity, and melting/crystallization behavior of pecan oil. In general, these properties in pecan oils were similar or superior to extra-virgin olive oil and unrefined sesame oil. Although all native pecan oils studied showed a significant concentration of oleic acid, a particular group of native Mexican pecan trees produces an oil with a fatty acid composition with the nutritional appeal that consumers demand nowadays (i.e., very high oleic acid, 60–75%), with excellent natural oxidative stability (i.e., induction time for oxidation between 8.5 and 10.8 h), and substantially higher concentrations of α-, γ-, and δ-tocopherol than in pecan varieties previously reported in the literature.     

The lipids of slugs and snails: Evolution,diet and biosynthesis

There is a considerable gap in current knowledge of the lipid composition of snails and slugs, both of which belong to the phylum Mollusca. We have therefore analyzed the sterol and fatty acid compositions of three species of slugs and three species of snails. The sterols of slugs included eight different sterols: cholesterol contributed 76–85% of the total sterols, brassicasterol accounted for 4–13%; other sterols we identified were lathosterol, 24-methylene cholesterol, campesterol, stigmasterol, sitosterol and sitostanol. In contrast, snails contained two additional sterols, desmosterol and cholestanol. Of the polyunsaturated fatty acids in slugs, linoleic (18∶2n−6) and arachidonic acids (20∶4n−6) were the major n−6 fatty acids, while linolenic (18∶3n−3) and eicosapentaenoic acids (20∶5n−3) were the predominant n−3 fatty acids. Docosahexaenoic acid (22∶6n−3), the end product in the n−3 fatty acid synthetic pathway and an important membrane fatty acid of mammals, fish and birds, was absent in both slugs and snails. However, the analogous product of n−6 fatty acid synthesis, 22∶5n−6, was found in both snails and slugs. This raises speculation about preference for n−6 fatty acid synthesis in these species. Our data show the unique sterol and fatty acid compositions of slugs and snails, as well as similarities and differences in sterol composition between the two. The results between the two land mollusks are contrasted with those of marine mollusks, such as oysters, clams and scallops.     

Association of seed size with genotypic variation in the chemical constituents of soybeans

Ten soybean genotypes grown in 1992 with seed size ranging from 7.6 to 30.3 g/100 seeds and maturity group V or VI were selected and tested for oil and protein content and for fatty acid composition. In these germplasm, protein varied from 39.5 to 50.2%, oil, 16.3 to 21.6%, and protein plus oil, 59.7 to 67.5%. Percentages of individual fatty acids relative to total fatty acids varied as follows: palmitic, 11.0 to 12.8; stearic, 3.2 to 4.7; oleic, 17.6 to 24.2; linoleic, 51.1 to 56.3 and linolenic, 6.9 to 10.0. Seed size showed no significant correlations with individual saturated fatty acids, protein or oil content. However, significant correlations were found between seed size and individual unsaturated fatty acids: positive with oleic, and negative with linoleic and linolenic. Oil and protein content were negatively correlated with each other. Among the major fatty acids, only the unsaturated were significantly correlated with each other: negative between oleic and linoleic or linolenic, and positive between linoleic and linolenic. A subsequent study with soybeans grown in 1993 generally confirmed these findings. Variation in relative percentages of unsaturated fatty acids andr values for most pairs of relationships were even higher than those obtained from the 1992 crop. Presented at the 85th AOCS Annual Meeting and Expo, Atlanta, Georgia, May 8–12, 1994.     

Fatty acid spectrum of mediterranean wild cruciferae

Seed samples of 54 species of wild Cruciferae were newly collected from natural populations of the west Mediterranean and adjacent areas in a search for “new” oil crops. Oil contents and fatty acid compositions were determined simultaneously by gas liquid chromatography using methyl heptadecanoate as the internal standard. The study revealed large variations in oil content (6–48.8%), oleic acid (5–31.3%), linoleic acid (2–24.8%), linolenic acid (1.7–64.1%), and erucic acid (0–55.1%). Correlation coefficients between component fatty acids inter se and oil content were determined separately for all species, the tribe Brassiceae, and the genusBrassica. The promising species identified are being studied further.