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1.
The seed oil of Hibiscus mutabilis (Chameleon rose) (Malvaceae) contains three HBr-reactive fatty acids. These are found to be cis-12, 13-epoxyoleic (vernolic) acid, 5.9%; 9,10-methylene-octadec-9-enoic (sterculic) acid. 7.3%; as well as 8,9-methylene-heptadec-8-enoic (malvalic) acid, 14.0%. Co-occurrence of these acids was established by combined spectroscopie, chromatographic and chemical techniques.  相似文献   

2.
Randall Wood  Rex D. Wiegand 《Lipids》1975,10(12):746-749
Monoenoic acid fractions were isolated from phosphatidycholine, phosphatidylethanolamine, triglycerides, and cholesteryl esters of hepatoma 7288CTC, host liver, and normal liver from animals maintained on chow and fat free diets. Hexadecanoate (16:1), octadecenoate (18:1), and eisosenoate (20:1) fractions were analyzed quantitatively for their isomeric composition. The fat free diet had little or no effect relative to the chow diet on the isomeric composition of 16:1, 18:1, and 20:1 from any lipid class in either heptoma, host liver, or normal liver. Host livers were reduced in palmitoleic acid, and oleic and eicos-11-enoic acids were increased relative to normal liver. The 16:1 fraction from triglyceride of normal liver, host liver, and hepatoma contained 90, 80, and 75% palmitoleic acid, respectively. The 20:1 fraction from triglycerides of normal liver, host liver, and hepatoma contained ca. 55, 70, and 60% eicos-11-enoic acid, respectively, with the remainder consisting of eicos-13-enoic acid. The proportion of vaccenic acid in the 18:1 fraction was 60, 50, 20, and 25% for phosphatidylethanolamine, phosphatidylcholine, triglycerides, and cholesteryl esters, respectively, with oleic acid making up the balance. In contrast, all hepatoma lipid classes exhibited the same proportion of oleic (70%) and vaccenic (30%) acids. These data appear to be the first to demonstrate lipid class specificity for isomeric octadecenoic acids in normal liver and the loss of this specificity in a neoplasm.  相似文献   

3.
Seed oil ofSemecarpus kurzii was found to contain 10.5% of 9-hydroxy-cis-12-enoic (isoricinoleic) acid along with the usual fatty acids. The identification of the hydroxy acid was made on the basis of chromatographic, spectroscopic and chemical methods, with isoricinoleic acid used as the reference standard.  相似文献   

4.
Pithecollobium dulce, Benth (syn.Inga dulcis, Willd) seed oil, belonging to the Leguminosae plant family, contains minor amounts of vernolic acid (12,13-epoxy-octadec-cis-9-enoic acid, 10.0%), malvalic acid [7-(2-octacyclopropen-1-yl)heptanoic acid, 3.2%], and sterculic acid [8-(2-octacyclopropen-1-yl)octanoic acid, 2.0%]. The other normal fatty acids are palmitic (12.1%), stearic (4.2%), behenic (10.6%), oleic (34.1%), and linoleic (23.8%). These fatty acids have been characterized by Fourier transform infrared,1H nuclear magnetic resonance, mass spectrometry and gas-liquid chromatography techniques and by chemical degradations.  相似文献   

5.
Rontani JF  Koblízek M 《Lipids》2008,43(11):1065-1074
The fatty acid composition of the marine phototrophic bacterium Erythrobacter sp. strain MG3 was analysed. The involvement of an unusual enzymatic peroxidation of the allylic carbon 10 of cis-vaccenic acid in this strain was confirmed. This process, which seems to be a characteristic of some aerobic and anaerobic phototrophic bacteria, appeared to also act on the allylic carbon 10 of octadeca-5,11-dienoic acid. Enzymatic degradation of 10-hydroperoxyoctadec-11(cis)-enoic acid resulting from the peroxidation of cis-vaccenic acid mainly involves reduction to the corresponding hydroxy acid (probably catalysed by peroxygenases) and cleavage to the corresponding oxoacid, which is then biohydrogenated. Abiotic degradation of this hydroperoxide involves allylic rearrangement to 10-hydroperoxyoctadec-11(trans)-enoic and 12-hydroperoxyoctadec-10(trans)-enoic acids and cyclisation to the very unusual 7,10-epoxyoctadec-11(cis)-enoic acid. Several tests carried out at different periods of growth and under different growth conditions allowed to show that the induction of this enzymatic peroxidation process strongly depends on the physiological state of the cells and is enhanced during C-limitation and at low temperatures.  相似文献   

6.
Rontani JF  Koblízek M  Beker B  Bonin P  Kolber ZS 《Lipids》2003,38(10):1085-1092
The origin of 11-hydroxyoctadec-trans-12-enoic and 12-hydroxyoctadec-trans-10-enoic acids (photodegradation products of cis-vaccenic acid) in the marine environment was investigated. cis-Vaccenic acid is commonly used as a bacterial biomarker; however, in heterotrophic bacteria the observed rates of cis-vaccenic acid photodegradation are negligible. Here, two hypotheses explaining the source of the photoproducts were tested. According to the first hypothesis, the photoproducts originate from aerobic anoxygenic bacteria, i.e., photoheterotrophic organisms using bacteriochlorophyll-containing reaction centers. Alternatively, the photoproducts come from a heterotrophic bacterial community closely associated with senescent phytoplanktonic cells. cis-Vaccenic acid photodegradation was detected in both experimental setups. However, a detailed comparison of the cis-vaccenic acid photodegradation patterns with those observed in particulate matter samples of the DYFAMED station (Mediterranean Sea) suggests that photodegradation of heterotrophic bacteria attached to senescent phytoplanktonic cells constitutes the more likely source of cis-vaccenic acid oxidation products detected in situ.  相似文献   

7.
D. Gompertz 《Lipids》1971,6(8):576-580
A child with propionicacidaemia due to a defective propionyl CoA carboxylase activity, accumulated odd number fatty acids in his liver. Seventeen carbon saturated and monounsaturated acids both represented 2% to 3% of the total liver fatty acids. The monounsaturated acid is demonstrated to be heptadec-9-enoic acid. The distribution of the 17 carbon saturated and monounsaturated acids throughout the major lipid classes is described. Enzymic degradation of lecithins and triglycerides is used to establish the positional specificity of esterification of these two fatty acids. The results indicate that when the only difference between two fatty acids, present in similar concentrations, is a single double bond, highly specific esterification patterns are retained.  相似文献   

8.
Chemical identification of the volatile decomposition products (VDP) produced by fats and oils under conditions of deep fat frying is important for the elucidation of the mechanisms of thermal oxidation, for the study of their effects upon human nutrition, and for their contribution to the deep fat fried flavor of foods. The acidic VDP produced by corn oil maintained at 185C for 30 hr with periodic frying of moist cotton balls and with addition of fresh oil to replenish the oil lost due to evaporation, decomposition, and adsorption by the cotton balls were fractionated by repeated gas chromatography. The gas chromatographic fractions were identified by IR and mass spectrometry. A total of 30 acids were characterized. They consisted of 12 n-aliphatic saturated acids, seven 2-enoic acids, one 3-enoic acid, three keto acids, two hydroxy acids, four dicarboxylic acid and one aromatic acid. It is suggested that the effects of some of these acids upon human nutrition be studied. Paper of the Journal Series, New Jersey Agricultural Experiment Station, Rutgers, The State University.  相似文献   

9.
Chiral 2-hydroxy-4-arylbut-3-enoic acid derivatives are important precursors for the synthesis of angiotensin converting enzyme (ACE) inhibitors, such as enalapril, lisinopril, cilapril or benazepril. In this work, we take advantage of the unexplored promiscuous ketoreductase activity of Δ1-piperidine-2-carboxylate/Δ1-pyrroline-2-carboxylate reductase from Pseudomonas syringae pv. tomato DSM 50315 (DpkAPsyrin) for the synthesis of (S,E)-2-hydroxy-4-arylbut-3-enoic acids. The strategy was designed as an enzymatic cascade comprising an aldol condensation between pyruvate with aryl aldehydes, catalyzed by the trans-o-hydroxybenzylidene pyruvate hydratase-aldolase from Pseudomonas putida (HBPAPputida), for the construction of carbon scaffold, and an ensuing asymmetric reduction of the carbonyl group catalyzed by DpkAPsyrin. The enzymatic cascade provided quantitative conversions, with global isolated yields between 57–85%. A total of nine structurally diverse (S,E)-2-hydroxy-4-arylbut-3-enoic acids were prepared in ee between 87–99%.  相似文献   

10.
Sterculia foetida oil contains cyclopropene fatty acids namely 8,9-methylene-heptadec-8-enoic acid (malvalic) and 9,10-methylene-octadec-9-enoic acid (sterculic) to an extent of 50–55%. The present study reports the preparation of biodiesel from S. foetida oil using sodium hydroxide as catalyst. The resultant biodiesel was evaluated for physico-chemical properties namely iodine value (72.6), free fatty acids (0.17%), phosphorous content (0 ppm), flash point (179 °C), cloud point (3 °C), pour point (3 °C), viscosity at 40 °C (4.72 cSt), oxidative stability at 110 °C (3.42 h), density (0.850 g/cm3 at 15 °C), and trace metals (Group I metals 0.21 ppm). The properties were compared with that of sunflower, soybean and rapeseed oil-based biodiesels and found to be comparable except for the pour point.  相似文献   

11.
The fatty acids of the spongeDysidea fragilis from the black sea   总被引:8,自引:8,他引:0  
The fatty acid composition of the sponge,Dysidea fragilis, from the Black Sea has been determined by analytical gas chromatography, silver ion high-performance liquid chromatography and gas chromatography/mass spectrometry. More than a hundred different fatty acids were identified, of which many were similar to those in sponges from tropical seas. On the other hand, some of the fatty acids identified have not been found previously in sponges or other marine sources and perhaps are new to science. These include 13-methyl-tetradec-4-enoic and 14-methyl-hexadec-6-enoic acids, together with demospongic acids,i.e. 5,9,17-tetracosatrienoic, 5,9,17-pentacosatrienoic and 5,9,19-pentacosatrienoic acids. From the elution behavior on silver nitrate chromatography, all the double bonds were of thecis-configuration.  相似文献   

12.
Alkylaluminium halide induced Friedel-Crafts acylations of unsaturated fatty compounds with acyl chlorides give the corresponding β,γ-unsaturated ketones. Acylation of oleic acid and 10-undecenoic acid with acetyl chloride yields (E)-9(10)-acetyloctadec-10(8)-enoic acid and 12-oxo-tridec-9-enoic acid, respectively. Acylation of 10-undecenoic acid with heptanoyl chloride followed by NaBH4-reduction gives ricinelaidic acid. The very interesting β,γ-unsaturated ketodicarboxylic acid (E)-9(10)-(1-oxo-3-carboxy-propyl)octadec-10(8)-enoic acid is obtained by acylation of oleic acid with succinic anhydride.  相似文献   

13.
Monohydroxylated acid fraction isolated from human meconium was found to contain, in addition to C20 and C24 acids identified previously, three C22 bile acids-(20S)-3α-hydroxy-23,24-bisnor-5β-cholan-22-oic, (20S)- and (20R)-3β-hydroxy-23,24-bisnor-chol-5-en-22-oic, and one C21 acid-3β-hydroxypregn-5-en-21-oic. These compounds were identified by capillary gas chromatography-mass spectrometry and by comparison with standards. It is postulated that these C22 acids, as well as the two monohydroxylated C24 bile acids (lithocholic and 3β-hydroxychol-5-enoic) are produced in the maternal intestine by microbial flora and transferred to the fetus through the placenta.  相似文献   

14.
The distribution of oleic, linoleic, linolenic, petroselinic, hexadec-9 and 11-enoic, sterculic, four conjugated octadecatrienoic acids, isolinolenic, and octadeca-6,9,12,15-tetraenoic acid in vegetable triglycerides has been studied by hydrolysis with pancreatic lipase. The results, discussed in terms of a selectivity factor, indicate that these unsaturated acids do not compete equally for the secondary hydroxyl group.  相似文献   

15.
The reaction of 10-undecenoic acid with lead tetraacetate (LTA) in the presence of acetic acid and anhydrous potassium acetate gave a eutectic mixture of 10(11)-acetoxy-11(10)-methylundecanoic acid (25%), 10,11-diacetoxyundecanoic acid (15%) and 5-(ω-carboxyoctyl) γ-butyrolactone (45%). Similar reaction withcis-9-octadecenoic acid yielded a eutectic mixture of 9(10)-acetoxy-10(9)-methyloctadecanoic acid (20%) and 4(5)-(ω-carboxyheptyl)-5-(4)-octyl γ-butyrolactone (40%). In the reaction withtrans-2-enoic acids (C16 and C18) products obtained were: 1,2-diacetoxypenta- and heptadecane (27%), 3-acetoxyhexa- and octadecanoic acid (31%) and 2-(2-penta- and heptadecyl) succinic anhydride (23%), respectively. The structures of individual compounds were characterized by spectral methods.  相似文献   

16.
A treatment of 12-hydroxyoctadec-cis-9-enoic acid (I) and 9-hydroxyoctadec-cis-12-enoic acid (II) in the presence of a catalytic amount of mercuric acetate reacts with Jones reagent to afford 9,12-dioxooctadecanoic acid in high yield, involving two different mechanistic routes.  相似文献   

17.
Seed oil of Sonchus oleraceus (Compositae) contains cis-12, 13-epoxyoctadec-cis-9-enoic acid (Vernolic, 13.7%). Structural details of this HBr-reactive acid are obtained through comparative chromatographic, spectral and chemical data with those of pure vernolic acid isolated from Vernonia anthelmintica seed oil. GLC analysis of the esters of S. oleraceus also showed a C14:1 acid (1.6%).  相似文献   

18.
Thetrans-3-enoic acids ofAster alpinus (dwarf aster, rock aster) andArctium minus (burdock) seed oils have been isolated and characterized.Arctium seed oil containstrans-3,cis-9,cis-12-octadecatrienoic acid (9.9%), andAster oil containstrans-3-hexadecenoic (7.1%),rans-3-octadecenoic (1.9%),trans-3,cis-9-octadecadienoic (3.0%),a ndtrans-3,cis-9,cis-12-octadecatrienoic (13.7%) acids.Aster oil also has an epoxy acid as a minor constituent (ca. 2.0%), which has been identified ascis-9,10-epoxy-cis-12-octadecenoic acid.  相似文献   

19.
对-氟苯酚与硫酸二甲酯进行酚甲醚化得到对-氟苯甲醚,然后在AlCl3催化下与顺丁烯二酸酐进行Friedel-Crafts酰基化,进一步去甲基化得到4-(4-氟-2-苯酚)-4-氧代-2-丁烯酸,在碱性条件下,经自身环化得到6-氟-4-氧代-3,4-二氢-2H-1-苯并吡喃-2-甲酸,关环步骤的收率为81%;最后在乙酸介质中,用5%Pd/C催化加氢得到外消旋的6-氟-3,4-二氢-2H-1-苯并吡喃-2-羧酸。该工艺总收率为51.87%,具有合成路线短、收率高、原料易得、条件温和、操作简单的特点,适宜工业化生产。  相似文献   

20.
We are presenting our results on the alkylaluminium halide catalyzed ene addition of formaldehyde to readily available unsaturated fatty compounds to give primary homoallylic alcohols. The reaction of oleic acid and 10-undecenoic acid with formaldehyde gives (E)-9(10)-(hydroxymethyl)octadec-10(8)-enoic acid and 12-hydroxydodec-9-enoic acid, respectively, in high yields. Formaldehyde can be added also to oleyl alcohol to give the very interesting diol (E)-9(10)-(hydroxymethyl)oxtadec-10(8)-en-l-ol. Me2AlCl and EtAl-sesquichloride are the most suitable catalysts for these reactions. The addition of formaldehyde to methyl oleate and methyl 10-undecenoate, respectively, to give the corresponding ene products is catalyzed by EtAlCl2.  相似文献   

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