Occurrence of 7-methyl-7-hexadecenoic acid,the corresponding alcohol, 7-methyl-6-hexadecenoic acid,and 5-methyl-4-hexadecenoic acid in sperm whale oils

Journal of the American Oil Chemists' Society -     

Distribution oftrans-6-hexadecenoic acid, 7-methyl-7-hexadecenoic acid and common fatty acids in lipids of the ocean sunfishMola mola

Lipids extracted from various tissues of four individual sunfish have been shown to contain thetrans-6-hexadecenoic acid previously reported for marine turtles, a metridium and a jelly fish, and also the 7-methyl-7-hexadecenoic acid recently isolated from one sunfish liver oil sample. The other fatty acids present were qualitatively typical of marine lipids in general. Unusual quantitative details included high percentages of 18∶0 and 20∶4ω6, which are also found in the Atlantic leatherback turtle and presumably linked to a similar diet of jellyfish and to other common factors. In a sample of lipids from intestinal contentstrans-6-hexadecenoic acid was found to be the predominant C₁₆ monoene, and was accompanied by comparatively large amounts of the 7-methyl-7-hexadecenoic acid. This observation and other fatty acid details are compatible with an exogenous origin for these acids and jellyfish, etc., as a predominant dietary material for the ocean sunfish.     

Occurrence of 7-methyl-7-hexadecenoic acid,the corresponding alcohol, 7-methyl-6-hexadecenoic acid,and 5-methyl-4-hexadecenoic acid in sperm whale oils

Two sperm whale oils from the northern hemisphere and two from the southern hemisphere were fractionated. Triglyceride and wax esters were examined for fatty acids and alcohols with monoethylenic unsaturation bearing a methyl branch on an ethylenic carbon. The 7-methyl-7-hexadecenoic acid (0.37-1.37%) was accompanied by the corresponding alcohol (0.28-0.72%), but these materials were not accompanied by shorter chain homologues. The 7-methyl-6-hexadecenoic acid was relatively less important (0.23-0.68%), but was accompanied by 5-methyl-4-hexadecenoic acid (0.10-0.39%), and a partially identified C13 compound. Chromatographic properties on silver nitrate impregnated silicic acid TLC and on three GLC liquid phases are reported.     

The fatty acid composition of a Vibrio alginolyticus associated with the alga Cladophora coelothrix. Identification of the novel 9-methyl-10-hexadecenoic acid

The fatty acid composition of a new strain of Vibrio alginolyticus, found in the alga Cladophora coelothrix, was studied. Among 38 different fatty acids, a new fatty acid, 9-methyl-10-hexadecenoic acid and the unusual 11-methyl-12-octadecenoic acid, were identified. Linear alkylbenzene fatty acids, such as 10-phenyldecanoic acid, 12-phenyldodecanoic acid and 14-phenyltetradecanoic acid, were also found in V. alginolyticus. The alga contained 43% saturated fatty acids, and 28% C₁₆–C₂₀ polyunsaturated fatty acids of the n−3 and n−6 families.     

trans-6-hexadecenoic acid in the spadefishChaetodipterus faber

Fatty acid methyl esters were prepared from spadefish (Chaetodipterus faber) liver oil and were analyzed by open tublar gas chromatography. The unusual fatty acidtrans-6-hexadecenoic acid was identified as a major monoenoic component by reductive ozonolysis and by mass spectrometry of the di-trimethylsilyl ether. Very minor amounts of 7-methyl-7-hexadecenoic acid were found.     

Alkyl glycerol monoethers in the marine spongeDesmapsamma anchorata

1-O-Hexadecylglycerol (chimyl alcohol), 1-O-heptadecylglycerol and 1-O-octadecylglycerol (batyl alcohol) have been identified as the major native constituents of a mixture of free alkyl glycerol ethers isolated from the contained water and the methanolic extract of the spongeDesmapsamma anchorata. Minor components were the free C₁₄, C₁₅, C₁₉, C₂₀ and C₂₁ alkyl glycerol monoethers. The alkyl glycerol monoethers were analyzed and identified by gas chromatography/mass spectrometry of their isopropylidene derivatives. This is the first report on the occurrence of free C₁₅, C₁₉, C₂₀ and C₂₁ alkyl glycerol monoethers in a sponge. Contribution No. 1241 from the Instituto de Química, UNAM. This work was presented in part at the First Lanbio Symposium, Trends in Natural Products Research: Prospects for Pharmacological and Agrochemical Applications, Asunción, Paraguay, August 6–10, 1993.     

A novel keto fatty acid from cassia occidentalis seed oil

A keto fatty acid (Z)-7-oxo-11-octadecenoic acid) has been isolated in appreciable amount (27.1%) from Cassia occidentalis seed oil. The identification was based on chemical and spectroscopic methods.     

Occurrence ofCis-6-hexadecenoic acid as the major component ofThunbergia alata seed oil

An unusual series of monoenoic fatty acids constitutes about 85% of the total acids in seed oil fromThunbergia alata. The major component in the oil,cis-6-hexadecenoic acid (82%), is accompanied by the homologous 4-tetradecenoic (ca. 0.2%) and 8-octadecenoic (1.8%) acids. Another homologous series is represented by 5-tetradecenoic (ca. 0.2%), 7-hexadecenoic (1.8%) and the familiar 9-octadecenoic (4.4%) acids. Traces (<0.1%) of three other acids, 6-tetradecenoic and 10- and 11-octadecenoic, are also present along with palmitic (5.8%), stearic (0.6%) and linoleic (2.2%) acids. Some of the monoenoic acids have not previously been known to occur in seed oils. Presented at the Fifth Great Lakes Regional Meeting of the American Chemical Society, Peoria, Illinois, 1971. No. Market. Nutr. Res. Div., ARS, USDA.     

Lipid and fatty acid compositions of a novel docosahexaenoic acid-producing marine bacterium

An unidentified bacterial strain, SCRC-21406, isolated from the intestine of a marine fish, Glossanodon semifasciatus, produced docosahexaenoic acid at 23% (mol/mol) [=28% (w/w)] of total fatty acids in a medium containing 0.5% (wt/vol) peptone and 0.1% (wt/vol) yeast extract at 12°C under atmospheric pressure. The cell yield was 0.43 g/L. The major lipids of the strain were phosphatidylethanolamine and phophatidylglycerol. Docosahexaenoic acid was localized at the sn-2 positions of both phospholipids. The amounts of polyunsaturated fatty acids other than docosahexaenoic acid were extremely small [<3% (mol/mol)]. Monousaturated fatty acids of the cis-7, cis-9 and cis-11 types were detected.     

Calculating the lodine value for marine oils from fatty acid profiles

The iodine values of marine oils were directly calculated from fatty acid profiles by using reacting ratios (calculation factors) between I₂ (iodine) and either the fatty acids bound to a triglyceride or the free fatty acids. A total of 20 factors were incorporated from C14:1 to C24:1, placed into an Excel® spreadsheet, and used to calculate the iodine values. The calculated values were then compared to the oil’s iodine value obtained by the traditional titration method. The results indicate that this method can be used to obtain the iodine value of marine oils directly from the oil’s fatty acid composition, thus giving two results from one analysis.     

Trans-6-hexadecenoic acid and the corresponding alcohol in lipids in the sea anemoneMetridium dianthus

Trans-6-hexadecenoic acid was found in polar lipids, triglycerides, was esters and diacylglyceryl ethers of the sea anemoneMetridium dianthus from Passamaquoddy Bay. The corresponding alcomaquoddy Bay. The corresponding alcohol also apparently occurs in the wax esters of this species. The long-chain (C₂₀, C₂₂) monoethylenic alcohols reported for other species of sea anemones from neighboring waters were absent and the major alcohol and glyceryl ether chain both had 16∶0 structures. The isomers of C₁₈ and C₂₀ monoethylenic fatty acids in polar lipids and triglycerides were unusual in their high proportion of theω ₇ isomer. These two lipids also contained higher proportion of the polyunsaturated fatty acids than the others.     

5,9,23-triacontatrienoic acid,principal fatty acid of the marine spongeChondrilla nucula

The marine spongeChondrilla nucula contains 34% 30∶3Δ5,9,23 in its total fatty acids. This nonmethylene-interrupted polyunsaturated acid, unknown in other living organisms, occurs mainly as an ester in phosphatidylethanolamine.     

Structure and biosynthesis of novel conjugated polyene fatty acids from the marine green algaAnadyomene stellata

Novel polyunsaturated fatty acids with four conjugated double bonds were found in extracts of the green macroalga,Anadyomene stellata. The isolation of five of these with different chain lengths and varying degrees of unsaturation −16∶5, 18∶4, 20∶5, 20∶6, and 22∶7—was accomplished by organic extraction followed by a combination of vaccum and high-performarce liquid chromatography. One of these that was a novel substance (22∶7) was characterized as 4ZZ,7Z,9E,13Z,16Z,19Z-docosaheptaenoic acid and assigned the trivial name stellaheptaenoic acid. The structure of this new compound, isolated as its methyl ester derivative, was deduced from detailed nuclear magnetic resonance, gas chromatography/mass spectrometry (GC/MS), and other spectroscopic methods. Incubation of a chloroplast preparation, isolated from a crude algal homogenate by differential centrifugation, with six unsaturated fatty acids (palmitoleic, 6Z,9Z,12Z,15Z-octadecatetraenoic acid, arachidonic acid, eicosapentaenoic acid, 7Z,10Z,13Z,16Z-docosatetraenoic acid, and 4Z,7Z,10Z,13Z,16Z,19Z-docosahexaenoic acid) resulted in substantially increased synthesis of unique tetraene compouds as detected by ultraviolet spectrophotometry and tentatively identified by GC/MS.     

7-Methyl-7-hexadecenoic acid: Isolation from lipids of the ocean sunfishMola mola (Linnaeus) 1758

A fatty acid amounting to several per cent of the acids in various samples of the liver oil of the ocean sunfishMola mola was isolated and characterized as 7-methyl-7-hexadecenoic acid. This acid and the previously reported 7-methyl-6-hexadecenoic acid are believed to be chiefly responsible for the 7-methylhexadecanoic acid observed in many fatty acid mixtures of marine origin after hydrogenation.     

A novel compound, 7,10-dihydroxy-8(E)-octadecenoic acid from oleic acid by bioconversion

Sixty-two cultures from the Agricultural Research Service (ARS) Culture Collection and 10 cultures isolated from soil and water samples in Illinois were screened for their ability to convert agricultural oils to value-added industrial chemicals. A new compound, 7,10-dihydroxy-8(E)-octadecenoic acid (DOD), was produced from oleic acid at a yield of greater than 60% by bacterial strain PR3 which was isolated from a water sample in Morton, IL. To our knowledge, DOD has not been previously reported. The optimum time, pH and temperature for the production of DOD were 2 days, 7.0, and 30°C, respectively. The production of DOD is unique in that it involves hydroxylation at two positions and rearrangement of the double bond of the substrate molecule.     

4′-溴-6-甲基-8-氰甲基黄酮的全合成

探索黄酮醋酸类化合物的合成方法。通过酰基化、Fries重排、氯甲基化、氰化、缩合及 I2 /DMSO/H2 SO4 关环氧化合成 4′-溴 -6-甲基 -8-氰甲基黄酮 ,获得了满意的收率 (69.5 % )。采用新方法合成了鲜见文献报道的两个新化合物 2′-羟基 -3′-氰甲基 -5′-甲基 -4-溴查耳酮和 4′-溴 -6-甲基 -8-氰甲基黄酮 ,并对各步主要产物进行了结构表征。该方法具有反应时间短、操作简便、收率好等优点。基黄酮     

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.     

A prostaglandin-like fatty acid from a species in the cyperaceae

A C₂₀ cyclic trihydroxy unsaturated fatty acid was isolated and characterized as a representative member of a group of oxygenated fatty acids from the aquatic sedge,Eleocharis microcarpa, Torr. Characterization of the compound as 11-hydroxy-14-(3,5-dihydroxy-2-methylcyclopentyl)-tetradec-9-ene-12-yneoic acid was accomplished by various chemical and spectral methods.