Identification of naturally occurringtrans,trans Δ5,9 fatty acids from the spongePlakortis halichondroides

The firsttrans fatty acids from a sponge have been isolated fromPlakortis halichondroides. The sponge was shown to contain theiso acids (5E,9E)-19-methyl-5,9-eicosadienoic, (5E,9E)-20-methyl-5,9-heneicosadienoic and (5E,9E)-21-methyl-5,9-docosadienoic acid, as well as theanteiso acids (5E,9E)-19-methyl-5,9-heneicosadienoic and (5E,9E)-20-methyl-5,9-docosadienoic acid together with the straight chain (5E,9E)-5,9-docosadienoic acid. The acids were shown by gas chromatography, Fourier transform infrared and¹³C nuclear magnetic resonance to contain thetrans configuration. An eicosadienoic acid, namely (6E,14E)-6,14-eicosadienoic acid, and 12-methyl-5-octadecenoic acid were also identified in a sponge for the first time. The fatty acids were shown to be the principal constituents of phosphatidylethanolamine and phosphatidylcholine. No sterols were found in the sponge. The results presented in this work should be helpful in taxonomy of Homoscleromorpha.     

The phospholipid fatty acids of the marine spongeXestospongia muta

The rare phospholipid fatty acids 3,7,11-trimethyldodecanoic (1), 5,9-hexadecadienoic (2) and 12-methyl-hexadecanoic (3) were identified in the marine spongeXestospongia muta. Branched fatty acids inX. muta accounted for 35% of the total fatty acid mixture. It was observed that the occurrence of the 5,9-hexadecadienoic acid (2) coincides with the complete absence of the very long chain fatty acid 5,9-hexacosadienoic. The acid 5,9,19-octacosatrienoic seems to be found in mostXestospongia species.     

Tropaeolum speciosum seed fat: A rich source ofcis-15-tetracosenoic andcis-17-hexacosenoic acids

Tropaeolum speciosum seed fat contains 41.6 wt %cis-15-tetracosenoic acid and 7.6 wt %cis-17-hexacosenoic acid. Unlike nasturtium seed fat (Tropaeolum majus), the 22∶1, 24∶1 and 26∶1 inT. speciosum triglycerides are almost entirely esterified at the 1,3 positions.     

Sponge fatty acids. 3. Occurrence of series of n−7 monoenoic andiso-5,9 dienoic long-chain fatty acids in the phospholipids of the marine spongeCinachyrella aff.schulzei keller

The fatty acid composition of phospholipids from the New Caledonian spongeCinachyrella aff.schulzei Keller was studied. More than 60 fatty acids were identified as methyl esters andN-acyl pyrrolidides by gas chromatography and gas chromatography/mass spectrometry. Two isoprenoid fatty acids also were shown to be present, namely 4,8,12-trimethyltridecanoic and 5,9,13-trimethyltetradecanoic acids. The unusual 6-tetradecenoic, 6-pentadecenoic, 12-nonadecenoic and 26-methylheptacosanoic (iso-28∶0) acids were found for the first time in sponge phospholipids. A series of six n−7 monoenoic long-chain fatty acids (C₂₃ to C₂₈) were identified, including the rare 16-tricosenoic, 18-pentacosenoic and 21-octacosenoic acids. Fifteen fatty acids possessing the typical 5,9 dienoic moiety accounted for 30% of the total fatty acid mixture. Two new fatty acids were identified, namely 5(Z)-octacosenoic and 27-methyl-5(Z),9(Z)-octacosadienoic (iso-5,9-29∶2). Based on gas chromatography/Fourier transform infrared experiments, the double bonds were assigned the (Z) configuration. For part 2 of this series, see Reference 1.     

Identification of 5,9-hexadecadienoic acid in the marine spongeChondrilla nucula

The fatty acid 5,9-hexadecadienoic was identified in the spongeChondrilla nucula. This is the shortest fatty acid with the Δ5,9 unsaturation yet isolated from a marine sponge.     

Occurrence ofcis-5,cis-9-Hexacosadienoic andcis-5,cis-9,cis-19-Hexacosatrienoic acids in the marine spongeMicrociona prolifera

Fatty acid analysis of the total lipids from the marine spongeMicrociona prolifera by gas liquid chromatography on an EGSS-X column revealed two major peaks with equivalent chain length values of 27.08 and 27.74. Each of these components was isolated as a separate band by thin layer chromatography on AgNO₃-silicic acid. Characterization of the two unknowns by IR spectroscopy, NMR, hydrogenation, and gas liquid chromatography revealed that the unknown acids weren-26∶2 andn-26∶3 containing only nonmethylene interruptedcis-double bonds. Reductive ozonolysis identified the 26∶2 ascis-5,cis-9-hexacosadienoic acid and the 26∶3 ascis-5,cis-9,cis-19-hexacosatrienoic acid. Analysis of the fatty acid composition ofMicrociona total lipids showed 14% 26∶2 and 31% 36∶3. The neutral lipids, phosphatidylethanomaline, and phosphatidylserine all contained >41% C₂₆ acids; but only 4% C₂₆ was present in the phosphatidylcholine.     

Occurrence,function and biosynthesis of wax esters in marine organisms

Wax esters occur as a major lipid-type in at least 30 species of marine animals, distributed among 17 orders and 3 phyla. They are of limited usefulness as a chemotaxonomic character, since only in two suborders, the calanoid copepods, Calanoidei, and the toothed whales, Odontoceti, do the wax esters occur in all members so far examined. In bony fishes their occurrence in muscle correlates better with mesopelagic habitat and vertical migration patterns than with taxonomy. Homologs with 21 to 44 total carbon atoms have been reported, but the usual range for the wax esters in copepods and fish is C₃₀–C₄₂. In fishes the muscle wax esters contain predominantly one and two double bonds per molecule, while in roe lipids up to 65% of the homologs contain three or more double bonds. The component alcohols are saturated and monounsaturated, with 16∶0 and 18∶1 as the usual major constituents. The fatty acids are more diverse, but 18∶1 is most often the main component, and 16∶1 and 20∶1 are frequent major constituents; polyunsaturated acids make up 1–12% in fish muscle and whale oils and up to 45% in fish roe wax esters. Possible functions of the wax esters are for buoyancy, as energy reserves and for thermal insulation. In vitro, various tissues of marine bony fishes synthesize wax esters from long chain alcohols and fatty acids, without activation. A competing pathway for the long chain alcohols in vivo is their catabolic oxidation to the corresponding fatty acids. The key to the accumulation of wax esters is to be sought in the metabolism of the long chain alcohols, their biosynthesis and esterification vs. their catabolism. Presented at the 60th AOCS Annual Meeting, San Francisco, April 1969, as part of a Symposium on Natural Waxes.     

Identification of the new 18-hexacosenoic acid in the spongeThalysias juniperina

The phospholipid fatty acids from the spongeSpheciospongia cuspidifera were studied revealing the presence of the rare 10-octadecenoic acid (10−18∶1) and a new 2-methoxyhexadecenoic acid. The phospholipid fatty acids fromThalysias juniperina were also studied revealing the presence of the hitherto unreported 18-hexacosenoic acid (18−26∶1). These results tend to indicate that the biosynthetic pathway from 10−18∶1 to 18−26∶1 may be operative in nature. The phospholipid mixture from the sponges was also analyzed by³¹P-NMR and shown to mainly consist of phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, and phosphatidylglycerol. Phosphatidylcholine was not found in the sponges analyzed in this work.     

Fatty acids of serine,ethanolamine, and choline plasmalogens in some marine bivalves

The FA composition of glycerophospholipid (GPL) classes and subclasses was investigated in whole animals of three marine bivalve mollusks: the Japanese oyster Crassostrea gigas, the blue mussel Mytilus edulis, and the Manila clam Ruditapes philippinarum. Individual organs (gills, mantle, foot, siphon, and muscle) of the Manila clam also were examined. The PS plasmalogen (PSplsm), PE plasmalogen (PEplsm), and PC plasmalogen (PCplsm) subclasses were isolated by HPLC, and their individual FA compositions were examined using GC. Plasmalogen forms of PS and PE, when compared to their respective diacyl forms, were found to be specifically enriched with non-methylene-interrupted (NMI) FA (7,15–22∶2, 7, 13–22∶2, and their precursors) and 20∶1n−11 FA. Such a clear specific association was not found for PCplsm. Interestingly, this trend was most apparent in PSplsm, and the above FA were found to be, respectively, the predominant PUFA and monounsaturated FA in the PSplsm isolated from the three species. This specificity was maintained in all the analyzed organs of the Manila clam but varied in proportions: The highest level of plasmalogens, NMI FA, and 20∶1n−11 was measured in gills and the lowest was in muscle. These results represent the first comprehensive report on a FA composition of the PSplsm subclass isolated from mollusks. The fact that NMI FA and 20∶1n−11, which are thought to be biosynthesized FA, were mainly associated with aminophospholipid plasmalogens (PE and PS) is likely to have a functional significance in bivalve membranes.     

Occurrence and significance of humic acids in ancient sediments

Under mild conditions humic acids persist in ancient sediments (up to 70% of the total organic matter). In most samples studied, there is a relation between humic acids and associated kerogens, and this is a possible way to obtain more information on the structure of kerogens. The occurrence of humic compounds characterizes the immature stage; they rapidly disappear with natural evolution, hence the humic content would be an interesting marker of evolution during the immature stage. Moreover these compounds may be compared with humic acids occurring in recent deposits; thus they are a valuable source of information about the original organic matter and deposit media.     

Arachidonic, 5, 11, 14, 17-eicosatetraenoic and related acids in plants—Identification of unsaturated fatty acids

Arachidonic and related fatty acids which normally are found only in animals or microorganisms have been isolated and identified from several mosses and ferns. Fatty acids with a double bond in position 5, separated by more than one methylene group from other double bonds, have been found inGinkgo biloba andEquisetum. Analyses of fatty acids from numberous plants, in particular their chlorophyll containing parts, are listed according to components. The experimental part gives details on structure determination of the usual methylene-interrupted fatty acids by ozonization-hydrogenation-GLC. Alkaline isomerization combined with these procedures was applied to determine the unusual double bond structures. The method permits positional identification of an internal double bond.     

Earthworm lipids: Occurrence of phytanic,pristanic and 4,8,12-trimethyltridecanoic acids

Lipids - Phytanic, pristanic, and 4,8,12-trimethyltridecanoic acids were found to comprise from 2.7% (winter) to 13.3% (spring) of the fatty acids of the neutral lipids of earthworms collected in...     

Occurrence and inheritance of linolenic and linoleic acids in soybean seeds

The range of linolenic acid in the oil from 251 field-grown varieties and introductions of soybeans was 4.89 to 9.28% and that of linoleic, 35.8 to 53.4%. Crosses of varieties and introductions “high” and “low” linolenic acid indicated that inheritance of both acids was quantitative rather than qualitative. Transgressive segregation, particularly to low values, was observed occasionally. However 3.35% was the lowest linolenic acid value observed. Environmental effects markedly influenced the quantity of both acids. F₂ plants from one cross (P.I.80476×P.I.85671), grown in the greenhouse, showed a dissimilar type of frequency distribution for the two acids but a significant positive correlation (P<1%) between their percentages. A similar relation was not detected for field-grown plants. Journal paper No. 1593, Purdue University Agricultural Experiment Station. Journal paper No. 346, U.S. Regional Soybean Laboratory. Crops Research Division, Agricultural Research Service, U.S. Department of Agriculture.     

Occurrence of unusual hexadecenoate fatty acids in hepatoma lipids

Cis-hexadecenoates isolated from rat liver and hepatoma 7288CTC lipids were analyzed for positional isomers by ozonolysis and capillary gas liquid chromatography. In addition to the Δ6, Δ7, Δ9 and Δ11 isomers found in both tissues, the hepatoma neutral and polar lipids contained relatively high percentages of Δ12 and Δ14 hexadecenoates that were virtually absent from liver. The occurrence of these unusual fatty acids may result from an error in lipid metabolism in the hepatoma.     

Variation of the lipids and fatty acids in marine shrimps consumed in Venezuela

There are three marine shrimp species in the Venezuelan internal market, two of them are native species, from fisheries, Farfantapenaeus brasiliensis and Litopenaeus schmitti, and one is an exotic species and farmed, L. vannamei. The objectives of this paper were to determine the possible variation of lipid content and fatty acid composition of these species, even under different culture conditions (e.g. feed used). The lipid content in all the species are higher (5 to 10 times) that the data from previous papers deal with marine shrimps, ranged from 4.8 to 10.9%, suggesting that its impact in the human health should be reviewed. At the same time, there were detected differences between the lipid content and fatty acids composition of the species. Wild L. schmitti had the highest lipid content (10.9%), following by wild F. brasiliensis (9.0%), cultured L. schmitti (4.8% to 7.1%) and cultured L. vannamei (5.1% to 6.2%). On the other hand, L. schmitti fed on commercial feed had the highest proportion of EPA and/or DHA, following by L. vannamei fed on the experimental feed, wild L. schmitti and fed with the experimental feed and wild F. brasiliensis.     

The origin of the marine polyunsaturated fatty acids. Composition of some marine plankton

Summary and Conclusions Shrimp, crabs, the marine diatomNitzschia closterium, Platymonas sp., and the fresh water algaChlorella pyrenoidosa were maintained or cultured in the laboratory. The crustacea were fed low-fat, cottonseed oil, and menhaden oil rations. The fatty acid composition of all groups, as well as that of native phytoplankton and zooplankton catches, were determined as the extinction coeffcients, (E _1% ^1cm. ), at wavelengths of maximum absorption. It was found that both shrimp and crabs lost much of their polyunsaturated acids on the fat-free diet and regained it again by ingestion, as do fish. The shrimp however appeared to synthesize more highly unsaturated acids from cottonseed oil than did other aquatic animals. Phytoplankton do produce a high level of polyunsaturated fatty acids. The importance of the determination of the structure of aquatic plant and animal fatty acids in the problem of the origin of the acids and their mechan ism of synthesis was discussed. Contribution from the Departments of Oceanography and Meteorology and of Biochemistry and Nutrition of the Agricultural and Mechanical College System of Texas, Oceanography and Meteorology Series No. 137; supported in part by Grant No. A-777 from the National Institutes of Health and Grant No. A-020 from the Robert A. Welch Foundation.     

Cardiac fatty acids in rats fed marine oils

Cardiac fatty acids were studied in young rats fed marine oils for 1 week. When the diet contained 0, 0.5, 1, 2, 4, 8 or 16% by weight of partially hydrogenated oil from Norwegian capelin, the concentration of fatty acids in the cardiac tissue was elevated only at the highest level. The amount of the lipid and the content of docosenoic acid in the heart were less than those observed with 15% partially hydrogenated oil from Canadian herring. Nonhydrogenated Peruvian anchovy oil lacking docosenoic acid produced no change in the amount of fat deposited. The extent of fatty acid accumulation in the heart was related to the dietary C₂₂ acids.     

Reaction of lipoxidase with polyenoic acids in marine oils

Eight samples of raw oils from fresh water and marine fish, and two from marine mammals, were examined for polyenoic fatty acids susceptible to the action of lipoxidase. The results agreed well in most instances with gas chromatographic data and indicated that only one peroxide group was formed in polyenoic fatty acids with more than one ostensibly suitable 1,4-pentadiene system. Four commercially available preparations of polyenoic fatty acids showed varying degrees of susceptibility to lipoxidase, indicating the probable presence of artifacts formed in purification steps. The marine polyenoic acids were suitable substrates for lipoxidase. Presented at the AOCS Meeting, New York October, 1968.