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1.
Biochim Biophys Acta ; 1082(2): 136-42, 1991 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-2007177

RESUMO

Cardiolipins from liver, heart and kidney mitochondria of rats fed a fat-free diet for 66 days have been analyzed for their fatty acid composition and positional distribution. The main effect was a dramatic decrease of linoleic acid which was counterbalanced by increases in the levels of palmitoleic, oleic and cis-vaccenic acids. Linoleic acid remains asymmetrically distributed between positions 1(1") and 2(2") with a positive selectivity for positions 1(1"). Its decrease is considerably faster in positions 2(2") than in positions 1(1"), which would suggest different rates of fatty acid turnover. Fat deficiency induces the appearance of 18:2(n-7) and a significant increase of 20:3(n-6) (dihomo-gamma-linolenic acid) in liver and kidney cardiolipins. In contrast, 20:3(n-6) level remains unchanged in other mitochondrial phospholipids. 18:2(n-7) and 20:3(n-6) are almost evenly distributed between both pairs of positions. Both acids have a common structural feature, that is double bonds in positions 8 and 11. 20:3(n-9) accumulates in large amounts in other mitochondrial phospholipids, but not in cardiolipins. Although surprising, 20:3(n-6) has thus to be considered as a specific marker of deficiency for cardiolipins when it is esterified to positions 1(1"). Taking into account various analytical data, it would appear that positions 1(1") of cardiolipins can only incorporate unsaturated fatty acids containing at least one cis double bond in position 8 or 9, with no other double bond between these positions and the carboxylic group.


Assuntos
Cardiolipinas/química , Gorduras na Dieta/farmacologia , Ácidos Graxos/química , Ácidos Linoleicos/metabolismo , Mitocôndrias/química , Animais , Esterificação , Rim , Masculino , Mitocôndrias Cardíacas/química , Mitocôndrias Hepáticas/química , Ratos , Ratos Endogâmicos , Fatores de Tempo
2.
Biochim Biophys Acta ; 1211(2): 198-206, 1994 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-8117747

RESUMO

In vivo-modified phospholipids from rat liver mitochondria were used to study the effect of trans-fatty acid incorporation into phospholipids on the steady-state fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) embedded in phospholipid liposomes. Pure fractions of mitochondria phospholipids were prepared and analyzed for their fatty acid compositions and fatty acid positional distribution. In rats fed a diet enriched with trielaidin, elaidic acid (trans-9 18:1 acid) was extensively incorporated in position 1 of phosphatidylcholine (PC; 31% of fatty acids esterified to this position), phosphatidylethanolamine (PE; 42.5%) and phosphatidylinositol (PI; 43%). Less than 10% of the incorporated elaidic acid was esterified to position 2 of these phospholipids. More than 90% of elaidic acid esterified to position 1 displaced saturated acids. Consequently, about one-third of PC molecules and two-fifths of PE and PI molecules contained one molecule of elaidic acid instead of one saturated fatty acid molecule in their 1-position. On the other hand, cardiolipin, which is naturally practically devoid of saturated acids, was particularly resistant to elaidic acid incorporation. The fluorescence polarization of DPH incorporated in liposomes made of PC-PI and of PC-PI-PE from liver mitochondria of rats fed or not fed elaidic acid was measured. No significant differences between phospholipids containing or not containing elaidic acid could be detected. Values of DPH fluorescence polarization for all samples were comprized between 0.133 and 0.135 at 25 degrees C. We thus conclude that when elaidic acid replaces saturated fatty acids in phospholipids, even in a high proportion (one-third), the physical state of acyl chains in the hydrophobic core of membranes is not grossly modified. Thus, elaidic acid seems to behave like a saturated fatty acid, not only biochemically for the acylation of phospholipids, but also physically.


Assuntos
Polarização de Fluorescência , Mitocôndrias Hepáticas/química , Ácido Oleico , Ácidos Oleicos/metabolismo , Fosfolipídeos/análise , Animais , Cardiolipinas/análise , Cardiolipinas/metabolismo , Difenilexatrieno , Ácidos Graxos/análise , Corantes Fluorescentes , Lipossomos/metabolismo , Masculino , Mitocôndrias Hepáticas/metabolismo , Ácidos Oleicos/análise , Fosfatidilcolinas/análise , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/análise , Fosfatidiletanolaminas/metabolismo , Fosfatidilinositóis/análise , Fosfatidilinositóis/metabolismo , Fosfolipídeos/metabolismo , Ratos , Ratos Wistar , Temperatura
3.
Biochim Biophys Acta ; 1168(3): 285-91, 1993 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8323968

RESUMO

Cardiolipins from mitochondria of different rat organs (heart; liver and kidney) appear to be privileged targets for the incorporation of cis-9,cis-12,trans-15 18:3 acid, a compound commonly found in deodorized edible linolenic acid-containing oils. When this acid (together with other linolenic acid geometrical isomers (LAGI)) is fed at high load to rats that had been reared on a fat-free diet since weaned for a few days, it replaces the endogenously synthesized monoenoic acids that had accumulated in cardiolipin during fat deficiency. Although there is no discrimination in deposition of any LAGI in adipose tissue triacylglycerols, a high selectivity of incorporation of the cis-9,cis-12,trans-15 18:3 acid over other isomers (including the all-cis 18:3(n-3) acid) is observed either in diradylphospholipids or in cardiolipins. However, cis-9,cis-12,trans-15 18:3 acid accumulates in cardiolipins at a considerably higher level than in other phospholipids (11 times in liver, 5-7 times in heart and kidney). It reaches 22-24% of total fatty acids in cardiolipins from heart and liver, and 13-14% in kidney. The cis-9,cis-12,trans-15 18:3 acid is esterified to both the 1(1")- and 2(2")-positions of liver mitochondria cardiolipin, with a well-marked selectivity for positions 1(1"). Its 1(1")/2(2") selectivity ratio is about the same as that of 18:2(n-6) acid: 2.1 vs 2.2. It is concluded that the trans-15 ethylenic bond is probably perceived as a single bond by enzymic systems that ensure acylation of cardiolipins. The cis-9,cis-12,trans-15 isomer is able to reverse the fatty acid modifications induced in cardiolipins by a diet devoid of essential fatty acids, in a way similar to that of 18:2(n-6) acid supplementation.


Assuntos
Cardiolipinas/metabolismo , Gorduras na Dieta/administração & dosagem , Ácidos Linolênicos/farmacocinética , Tecido Adiposo/metabolismo , Animais , Ácidos Graxos/análise , Isomerismo , Rim/metabolismo , Lipídeos/deficiência , Masculino , Mitocôndrias/metabolismo , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Hepáticas/metabolismo , Fosfolipídeos/metabolismo , Ratos , Ratos Wistar
4.
Am J Med ; 68(2): 238-42, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7188831

RESUMO

We observed seven episodes of Aeromonas hydrophila septicemia in five patients. All but one patient had an underlying disease resulting in immunosuppression. All episodes occurred in ambulatory patients whose vocation or avocation had recently caused them to contact water or fish. We hypothesize that infection with this gram-negative bacterium is acquired more frequently from the natural habitat of the organism than from nosocomial sources.


Assuntos
Aeromonas , Terapia de Imunossupressão , Sepse/etiologia , Microbiologia da Água , Adolescente , Idoso , Amputação Traumática/complicações , Anemia Aplástica/complicações , Animais , Exposição Ambiental , Peixes , Passatempos , Humanos , Leucemia/complicações , Masculino , Pessoa de Meia-Idade , Transtornos Mieloproliferativos/complicações
5.
Artigo em Inglês | MEDLINE | ID: mdl-10883062

RESUMO

The goal of this study was to compare the lipid lowering properties of maritime pine and fish oils in apolipoprotein E-deficient (KOE) mice, an animal model of hyperlipidemia. KOE mice were supplemented with either lard, fish or maritime pine oil (10% w/w) for one month. Compared to lard, fish and maritime pine oils decreased cholesterol (-31% and -52% respectively) and phospholipid (-41 and -52%) levels and increased triglyceride (+182% and +123%) levels. These lipid changes resulted in an enrichment in triglycerides and a depletion in cholesterol of VLDL+IDL plasma fraction as compared to lard-fed mice. These findings suggest that VLDL-triglyceride lipolysis is impaired in KOE mice fed fish or maritime pine oil.


Assuntos
Apolipoproteínas E/deficiência , Óleos de Peixe/farmacologia , Lipoproteínas/efeitos dos fármacos , Óleos de Plantas/farmacologia , Animais , Colesterol/sangue , Cromatografia em Gel , Gorduras na Dieta/farmacologia , Modelos Animais de Doenças , Hiperlipidemias/sangue , Lipídeos/sangue , Lipoproteínas/sangue , Lipoproteínas/química , Lipoproteínas LDL/sangue , Lipoproteínas LDL/química , Lipoproteínas VLDL/sangue , Lipoproteínas VLDL/química , Masculino , Biologia Marinha , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fosfolipídeos/sangue , Árvores
6.
Eur J Clin Nutr ; 49(7): 523-31, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7588503

RESUMO

OBJECTIVE: The aim of the present study was to identify the trans isomers of C18 fatty acids in some human milk samples. SUBJECTS: Ten human milk samples from French women were collected in a local milk bank in order to assess their trans mono and polyunsaturated fatty acids (PUFA) content. INTERVENTION: The fatty acid profile was examined using methyl and isopropyl ester derivatives. The combination of gas-liquid chromatography, high-performance liquid chromatography and silver nitrate thin-layer chromatography was needed to describe the detailed fatty acid compositions, including the trans isomers of unsaturated C18 fatty acids. RESULTS: All the samples contained trans isomers of C18:1 acid (mean level 1.9 +/- 0.2% of total fatty acids), with trans vaccenic acid being the major isomer. The samples also contained various isomers of linoleic and alpha-linolenic acid, but at lower levels. Trans isomers of PUFA are the same as those present in deodorised or deep-fried oils. One sample presented an abnormally high degree of isomerisation of alpha-linolenic acid (almost 50%). This was related to the dietary habit or consuming foods that were deep-fried in rapeseed oil. This milk sample also contained some cyclic fatty acid monomers. CONCLUSION: The human milk samples collected in this study contained some trans fatty acids, including isomers of essential fatty acids. This should be taken into account in the dietary intake of the newborn.


Assuntos
Ácidos Graxos Monoinsaturados/análise , Ácidos Graxos Insaturados/análise , Leite Humano/química , Adulto , Cromatografia Líquida de Alta Pressão , Ácidos Graxos Insaturados/química , Feminino , Humanos , Lactação , Estereoisomerismo
7.
Lipids ; 30(10): 893-8, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8538375

RESUMO

When rats were fed elaidic (trans-9 18:1) acid at a high load in diets that were otherwise marginally or almost completely deficient in linoleic (cis-9,cis-12 18:2) acid, elaidic acid was desaturated to cis-5,trans-9 18:2 acid. This polymethylene-interrupted acid was then incorporated into most phospholipids from rat mitochondria, cardiolipin being an exception. Its level of esterification in phospholipids followed the increasing order: phosphatidylethanolamine < phosphatidylcholine < phosphatidylinositol (PI). The content of cis-5,trans-9 18:2 acid decreased in organs in the order liver > kidney > heart. The levels of cis-5,trans-9 18:2 acid increased in mitochondria phospholipids as the level of linoleic acid was lowered in the diet. In liver mitochondria PI, it reached 16% of total fatty acids. After hydrolysis of liver mitochondria PI with Naja naja phospholipase A2, we observed that elaidic acid was essentially esterified to position 1 at the expense of saturated acids, whereas cis-5,trans-9 18:2 acid was exclusively esterified to position 2, along with 20:3n-9 and 20:4n-6 acids. As a consequence, the sums of saturated and trans-9 18:1 acids on the one hand, and of 20:3n-9, 20:4n-6, and cis-5,trans-9 18:2 acids on the other hand, remained fairly constant in liver mitochondria PI (ca. 55 and 30%, respectively). Because trans-9 18:1 and cis-5,trans-9 18:2 acids differ only by the cis-5 ethylenic bond, which is also present in 20:3n-9 and 20:4n-6 acids, this distribution pattern indicates that the cis-5 double bond, rather than any other ethylenic bond, may be of major structural importance for channeling fatty acids to position 2 of PI.


Assuntos
Gorduras na Dieta/metabolismo , Etilenos/química , Ácidos Graxos Dessaturases/metabolismo , Mitocôndrias/química , Ácido Oleico , Ácidos Oleicos/química , Ácidos Oleicos/metabolismo , Fosfatidilinositóis/metabolismo , Acilação , Animais , Cardiolipinas/metabolismo , Gorduras na Dieta/administração & dosagem , Esterificação , Rim/ultraestrutura , Ácido Linoleico , Ácidos Linoleicos/administração & dosagem , Masculino , Mitocôndrias/metabolismo , Mitocôndrias Cardíacas/química , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Hepáticas/química , Mitocôndrias Hepáticas/metabolismo , Ácidos Oleicos/administração & dosagem , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo , Fosfolipases A/metabolismo , Fosfolipases A2 , Ratos , Ratos Wistar
8.
Lipids ; 20(12): 908-14, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4094521

RESUMO

Pure cardiolipins (1,3-diphosphatidylglycerol) were prepared from mitochondria of heart, liver and kidney from 21-day-old male Wistar rats and submitted to Naja 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'') acyl sn-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 of cis-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'').(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Cardiolipinas/isolamento & purificação , Mitocôndrias/análise , Animais , Cromatografia Gasosa , Ácidos Graxos/análise , Rim/análise , Masculino , Mitocôndrias Cardíacas/análise , Mitocôndrias Hepáticas/análise , Especificidade de Órgãos , Fosfolipases A , Fosfolipases A2 , Ratos , Ratos Endogâmicos
9.
Lipids ; 36(6): 567-74, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11485159

RESUMO

Conifer (pine) seeds are a potential source of dietary oils, but their safety and nutritional properties are not well established. Conifer seed oils differ from common edible vegetable oils in having a series of unusual polyunsaturated fatty acids (PUFA) with a polymethylene-interrupted (PMI) double bond system and a double bond at the delta5 position. A rat study was conducted to assess whether delta5 PMI-PUFA of conifer seeds could alter the levels of n-6 and n-3 long-chain polyunsaturated fatty acids (LC-PUFA) in mothers' milk and the developing brain of fetuses and pups. Feeding maritime pine (Pinus pinaster) seed oil (MPO) diet with a delta5 PMI-PUFA content of 1.4 g/100 g throughout pregnancy and lactation resulted in a large incorporation of delta5 PMI-PUFA in mothers' milk (5.1 +/- 0.5% of total fatty acids). The fetus (17 d old) and pup (22 d) brains, however, accumulated very little (0.6 and 0.4% of total fatty acids, respectively) delta5 PMI-PUFA. Mother's milk and pup's brain of the MPO group contained normal levels of 20:4n-6, 22:4n-6, and 20:5n-3 compared to a reference group of rats fed a fat blend of sunflower, high-oleic sunflower, and canola oils. The level of 22:6n-3, however, was slightly but significantly (P < 0.05) higher in milk and pup brain of the MPO group. These results show that delta5 PMI-PUFA of MPO exert no negative effect on the levels of n-6 and n-3 LC-PUFA in rat brain during its early development.


Assuntos
Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Ácidos Graxos Insaturados/farmacologia , Ácidos Graxos/metabolismo , Óleos de Plantas/farmacologia , Prenhez/metabolismo , Animais , Animais Recém-Nascidos , Ácido Araquidônico/metabolismo , Ácidos Araquidônicos/farmacologia , Peso Corporal/efeitos dos fármacos , Encéfalo/embriologia , Mama , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Graxos/análise , Ácidos Graxos Ômega-3 , Ácidos Graxos Insaturados/metabolismo , Feminino , Lactação , Contagem de Leucócitos , Fígado/efeitos dos fármacos , Fígado/fisiologia , Glândulas Mamárias Animais/efeitos dos fármacos , Leite/química , Leite/metabolismo , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Pinus , Gravidez , Ratos , Ratos Wistar , Sementes/química , Triglicerídeos/metabolismo
10.
Lipids ; 36(3): 319-21, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11337989

RESUMO

A previously undescribed fatty acid, all-cis 7,11-20:2 (dihomotaxoleic acid, DHT), has been characterized by gas chromatography-mass spectrometry as being present (approximately 0.1%) in seed oils of two Taxaceae containing high levels (11-16%) of taxoleic acid (all-cis 5,9-18:2). This compound was absent from oils of 10 other conifer genera, as well as from one member of Taxaceae containing very low amounts of taxoleic acid, suggesting that DHT is a taxoleic acid elongation product.


Assuntos
Ácidos Graxos Insaturados/análise , Plantas Medicinais , Sementes/química , Taxus/química , Ácidos Graxos Insaturados/química , Cromatografia Gasosa-Espectrometria de Massas , Óleos de Plantas/análise , Especificidade da Espécie
11.
Lipids ; 20(6): 367-72, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-4021743

RESUMO

Effects of dietary trielaidin upon the alkenyl chain profile of plasmalogens were studied using heart mitochondria of rats fed a semi-purified diet containing 10% of fat supplement in which elaidic acid accounted for 69% of total fatty acids. Alkyl substituted dioxane (ASD) derivatives of the alkenyl groups of plasmalogens were prepared and analyzed by silver nitrate TLC and by GLC on different phases (BDS and OV-275). After two months of feeding the experimental diet, 40% of the ASD contained a trans-octadecenyl chain, suggesting that dietary elaidic acid was reduced in vivo to the corresponding alcohol and incorporated into plasmalogens. There was a simultaneous decrease in the percentage of ASD containing saturated chains, but the percentage of ASD substituted with cis-octadecenyl chains was not significantly affected. These observations suggested that elaidic acid may compete with saturated fatty acids, but not with cis-octadecenoic acids during the plasmalogen biosynthesis. Feeding trielaidin did not seem to have any significant influence on the relative proportions of plasmalogens, which accounted for 11-12%, on a phosphorus basis, of total heart mitochondria phospholipids.


Assuntos
Mitocôndrias Cardíacas/metabolismo , Ácido Oleico , Ácidos Oleicos/farmacologia , Plasmalogênios/metabolismo , Animais , Dieta , Gorduras na Dieta/análise , Ácidos Graxos/análise , Técnicas In Vitro , Lipídeos/isolamento & purificação , Masculino , Plasmalogênios/análise , Ratos , Ratos Endogâmicos
12.
Lipids ; 32(9): 971-3, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9307939

RESUMO

14-Methylhexadecanoic (14-MHD) acid has been identified in a sample of pine seed oil (Pinus contorta) by gas-liquid chromatography-mass spectrometry of its picolinyl ester derivative. Its identification (through its equivalent chain length) and its distribution in four conifer families have been checked. It occurred only in Pinaceae, where it was found in 72 species belonging to the genera Pinus, Abies, Cedrus, Tsuga, Pseudotsuga, Larix, and Picea, in the range 0.02-1.15%. 14-MHD acid could not be detected in the lipids of Taxaceae (Taxus baccata), Cupressaceae (Juniperus communis), or Taxodiaceae (Sciadopytis verticillata), even after a 10-fold concentration of the saturated acid fraction isolated by argentation thin-layer chromatography. It is concluded that Pinaceae, along with Ginkgo biloba seed lipids, are major exceptions in the plant kingdom with regard to 14-MHD acid, which otherwise occurs almost exclusively in lipids of animals and microorganisms. The biosynthesis and metabolic role of 14-MHD acid, which otherwise also occur in wood and leaf lipids, remain unknown.


Assuntos
Ácidos Palmíticos/análise , Óleos de Plantas/química , Cromatografia em Camada Fina , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Óleos de Plantas/análise , Sementes/química , Árvores
13.
Lipids ; 25(12): 859-62, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2093147

RESUMO

The use of a capillary column coated with 100% cyanopropyl polysiloxane (CP(TM)Sil 88) allows the separation of several fatty acids associated with fat deficiency. Starting with liver mitochondrial phospholipids of weanling rats fed a fat-free diet, an unusual fatty acid was isolated, along with 20:4n-6, by thin-layer chromatography on AgNO3-impregnated silica gel plates. After partial hydrazine reduction of these acids, the resulting monoenes were isolated and subjected to ozonolysis in BF3/methanol. The resulting monomethyl and dimethyl esters were identified by gas chromatography/mass spectrometry. Our data indicate that the unusual component corresponds to 20:4n-7. Based on published biochemical and analytical studies and on our own chromatographic retention data, some of the other unusual fatty acids were tentatively identified as 18:2n-7, 20:2n-7 and 20:3n-7. The CP(TM)Sil 88 column appears to be a simple and useful tool for the separation of fatty acids of the palmitoleate series.


Assuntos
Ácidos Graxos/análise , Mitocôndrias Hepáticas/química , Animais , Cromatografia Gasosa/métodos , Cromatografia em Camada Fina , Cromatografia Gasosa-Espectrometria de Massas , Ratos
14.
Lipids ; 34(10): 1083-97, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10580336

RESUMO

The fatty acid composition of the seeds from Agathis robusta, an Australian gymnosperm (Araucariaceae), was determined by a combination of chromatographic and spectrometric techniques. These enabled the identification of small amounts of arachidonic (5,8,11,14-20:4) and eicosapentaenoic (5,8,11,14,17-20:5) acids for the first time in the seed oil of a higher plant. They were apparently derived from gamma-linolenic (6,9,12-18:3) and stearidonic (6,9,12,15-18:4) acids, which were also present, via chain elongation and desaturation, together with other expected biosynthetic intermediates [bis-homo-gamma-linolenic (8,11,14-20:3) and bishomo-stearidonic (8,11,14,17-20:4) acids]. Also present were a number of C20 fatty acids, known to occur in most gymnosperm families, i.e., 5,11-20:2, 11,14-20:2 (bishomo-linoleic), 5,11,14-20:3 (sciadonic), 11,14,17-20:3 (bishomo-alpha-linolenic), and 5,11,14,17-20:4 (juniperonic) acids. In contrast to most other gymnosperm seed lipids analyzed so far, A. robusta seed lipids did not contain C18 delta5-desaturated acids [i.e., 5,9-18:2 (taxoleic), 5,9,12-18:3 (pinolenic), or 5,9,12,15-18:4 (coniferonic)]. These structures support the simultaneous existence of delta6- and delta5-desaturase activities in A. robusta seeds. The delta6-ethylenic bond is apparently introduced into C18 polyunsaturated acids, whereas the delta5-ethylenic bond is introduced into C20 polyunsaturated acids. A general metabolic pathway for the biosynthesis of unsaturated fatty acids in gymnosperm seeds is proposed. When compared to Bryophytes, Pteridophytes (known to contain arachidonic and eicosapentaenoic acids), and species from other gymnosperm families (without such acids), A. robusta appears as an "intermediate," with the C18 delta6-desaturase/C18-->C20 elongase/C20 delta5-desaturase system in common with the former subphyla, and the unsaturated C18-->C20 elongase/C20 delta5-desaturase system specific to gymnosperms. The following hypothetical evolutionary sequence for the C18 delta6/delta5-desaturase class in gymnosperm seeds is suggested: delta6 (initial)-->delta6/delta5 (intermediate)-->delta5 (final).


Assuntos
Ácidos Araquidônicos/metabolismo , Ácido Eicosapentaenoico/metabolismo , Plantas/metabolismo , Sementes/metabolismo , Cromatografia , Ácidos Graxos/metabolismo , Análise Espectral
15.
Lipids ; 36(11): 1247-54, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11795858

RESUMO

Dibutyroyl derivatives of monoacylglycerols (DBMAG) from conifer seed oil triacylglycerols (TAG) were prepared by partial deacylation of TAG with ethylmagnesium bromide followed by diesterification with n-butyryl chloride. The resulting mixtures were analyzed by gas-liquid chromatography (GLC) with a 65% phenylmethyl silicon open tubular fused-silica capillary column operated under optimal conditions and separated according to both their fatty acid structures and their regiospecific distribution. Seed oils of 18 species from 5 conifer families (Pinaceae, Taxaceae, Cupressaceae, Cephalotaxaceae, and Podocarpaceae) were analyzed. The chromatograms showed a satisfactory resolution of DBMAG containing palmitic (16:0), stearic (18:0), taxoleic (cis-5,cis-9 18:2), oleic (cis-9 18:1), cis-vaccenic (cis-11 18:1), pinolenic (cis-5,cis-9,cis-12 18:3), linoleic (cis-9,cis-12 18:2), alpha-linolenic (cis-9,cis-12,cis-15 18:3), and an almost baseline resolution of DBMAG containing gondoic (cis-11 20:1), cis-5,cis-11 20:2, sciadonic (cis-5,cis-11,cis-14 20:3), dihomolinoleic (cis-11,cis-14 20:2), juniperonic (cis-5,cis-11,cis-14,cis-17 20:4), and dihomo-alphalinolenic (cis-11,cis-14,cis-17 20:3) acids. We have observed that results for Pinus pinaster and P. koraiensis seed oils obtained with this new simple method compared favorably with literature data established with other usual regiospecific analytical techniques. Delta5-olefinic acids are esterified mainly at the external positions of the glycerol backbone in all cases, in agreement with data obtained by other methodologies allowing validation of the GLC regiospecific method. To date, 45 gymnosperm species (mostly Coniferophytes) from 21 genera belonging to 9 families have been analyzed, all of them showing a definite enrichment of delta5-olefinic acids in the external positions of TAG. These fatty acids (FA), with one exception only, represent between approximately 2 and 8% of FA esterified to the internal positions. For some species, i.e., P. koraiensis and P. pinaster, this asymmetrical distribution was established by at least three analytical procedures and confirmed by stereospecific analysis of their seed TAG.


Assuntos
Alcenos/análise , Cromatografia Gasosa/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cycadopsida/química , Sementes/química , Triglicerídeos/análise , Alcenos/química , Ácidos Graxos/análise , Isomerismo , Reprodutibilidade dos Testes , Triglicerídeos/química
16.
Lipids ; 36(10): 1175-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11768163

RESUMO

The distribution profiles of individual trans- as well as cis-18:1 isomers from the fat prepared from the hump adipose tissue and the milk from Camelus dromedarius (the single-humped Arabian species) are described. Gas-liquid chromatography on two capillary columns with different polarities and lengths were used for this purpose in combination with argentation thin-layer chromatography. A comparison of the profiles established is made with that of true ruminant fats. In the fats from the dromedarius as well as from true ruminants, the trans-18:1 isomers have their ethylenic bonds in all positions between delta4 and delta16. The prominent trans isomer is the 11-18:1 (vaccenic) acid in all species, and the complete distribution profiles are quite similar. Concerning the cis isomers, the prominent isomer is oleic acid, followed by cis-vaccenic acid, as in true ruminant fats. Other cis isomers encompass the delta6-8 and the delta12 to delta15 isomers. Camelidae (suborder Tylopoda) and Bovidae (suborder Ruminantia) have evolved independently since the Eocene, that is for approximately 50 million years. Despite this considerable period, and the profound differences in anatomy, morphology, physiology, ecological and dietary habits between the extant species of these suborders, the rumen microflora has continued to synthesize the same trans- and cis-octadecenoic acid isomers, in comparable proportions, at least as deduced from their composition profiles. We conclude that the trans-18:1 acid profile is not intrinsically species-dependent, but it can be affected by the nature and the proportions of dietary unsaturated fatty acids that themselves depend on the feed, and that may be species-specific.


Assuntos
Tecido Adiposo/química , Camelus , Leite/química , Ácidos Esteáricos/análise , Animais , Bovinos , Gorduras/química , Isomerismo , Ruminantes , Especificidade da Espécie
17.
Lipids ; 36(8): 827-32, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11592734

RESUMO

The trans- as well as the cis-18:1 isomer profiles were established in cow, goat, and ewe cheese fats, with the assumption that these are representative of the corresponding milks. Argentation thin-layer chromatography was combined with low-temperature high-resolution gas-liquid chromatography on 100-m highly polar capillary columns, thus adding precision to earlier data for these species. Despite differences in the absolute content of trans-18:1 isomers between species, the relative profiles were essentially similar. Except for the minor trans delta6-delta8 group, all trans-18:1 isomers with their ethylenic bonds between positions delta4 and delta16 (including the resolved critical pair delta13/delta14) were separated and quantitated individually. As expected, vaccenic (trans delta9-18:1) acid was the main isomer, accounting for as much as 37 to 50% of the total fraction. It was observed that the goat trans-18:1 isomer profile was usually rather close to that of cows in winter (barn feeding), whereas that of the ewe shows a seasonal dependence. The trans-18:1 profile of ewe milk fats from this study resembles that of cows in the transition period between winter and summer (pasture) feeding. Regarding the cis-18:1 acid fraction, two isomers (oleic and cis-vaccenic acids) accounted for ca. 97% of that fraction for the three species, with the cis-delta12 isomer ranked third. The analytical procedure employed here appears a convenient alternative to oxidative-based procedures (generally ozonolysis), taking less time and alleviating some drawbacks of the latter procedure.


Assuntos
Cromatografia Gasosa/métodos , Ácidos Graxos/análise , Leite/química , Animais , Bovinos , Queijo , Ácidos Graxos/química , Cabras , Ovinos , Especificidade da Espécie , Temperatura
18.
Lipids ; 35(1): 1-22, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10695919

RESUMO

The delta5-unsaturated polymethylene-interrupted fatty acid (delta5-UPIFA) contents and profiles of gymnosperm seeds are useful chemometric data for the taxonomy and phylogeny of that division, and these acids may also have some biomedical or nutritional applications. We recapitulate here all data available on pine (Pinus; the largest genus in the family Pinaceae) seed fatty acid (SFA) compositions, including 28 unpublished compositions. This overview encompasses 76 species, subspecies, and varieties, which is approximately one-half of all extant pines officially recognized at these taxon levels. Qualitatively, the SFA from all pine species analyzed so far are identical. The genus Pinus is coherently united--but this qualitative feature can be extended to the whole family Pinaceae--by the presence of delta5-UPIFA with C18 [taxoleic (5,9-18:2) and pinolenic (5,9,12-18:3) acids] and C20 chains [5,11-20:2, and sciadonic (5,11,14-20:3) acids]. Not a single pine species was found so far with any of these acids missing. Linoleic acid is almost always, except in a few cases, the prominent SFA, in the range 40-60% of total fatty acids. The second habitual SFA is oleic acid, from 12 to 30%. Exceptions, however, occur, particularly in the Cembroides subsection, where oleic acid reaches ca. 45%, a value higher than that of linoleic acid. Alpha-linolenic acid, on the other hand, is a minor constituent of pine SFA, almost always less than 1%, but that would reach 2.7% in one species (P. merkusii). The sum of saturated acids [16:0 (major) and 18:0 (minor) acids principally] is most often less than 10% of total SFA, and anteiso-17:0 acid is present in all species in amounts up to 0.3%. Regarding C18 delta5-UPIFA, taxoleic acid reaches a maximum of 4.5% of total SFA, whereas pinolenic acid varies from 0.1 to 25.3%. The very minor coniferonic (5,9,12,15-18:4) acid is less than 0.2% in all species. The C20 elongation product of pinolenic acid, bishomo-pinolenic (7,11,14-20:3) acid, is a frequent though minor SFA constituent (maximum, 0.7%). When considering C20 delta5-UPIFA, a difference is noted between the subgenera Strobus and Pinus. In the former subgenus, 5,11-20:2 and sciadonic acids are < or =0.3 and < or =1.9%, respectively, whereas in the latter subgenus, they are most often > or =0.3 and > or =2.0%, respectively. The highest values for 5,11-20:2 and sciadonic acids are 0.5% (many species) and 7.0% (P. pinaster). The 5,11,14,17-20:4 (juniperonic) acid is present occasionally in trace amounts. The highest level of total delta5-UPIFA is 30-31% (P. sylvestris), and the lowest level is 0.6% (P. monophylla). Uniting as well as discriminating features that may complement the knowledge about the taxonomy and phylogeny of pines are emphasized.


Assuntos
Cycadopsida/classificação , Ácidos Graxos Insaturados/análise , Sementes/química , Árvores/classificação , Filogenia
19.
Lipids ; 35(9): 1027-32, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11026624

RESUMO

Low-temperature gas-liquid chromatography (GLC) was applied to study the distribution profiles of isomeric trans- and cis-hexadecenoic acids in ruminant (cow, goat, and ewe) milk fat after their fractionation by argentation thin-layer chromatography (Ag-TLC). The fat was extracted from cheeses (12 samples of each species), the most common foods made with goat and ewe milks. The predominant trans-16:1 isomer is palmitelaidic acid (the delta9 isomer), but it does not exceed one-third of the total group, which itself represents 0.17% (cow), 0.16% (goat), and 0.26% (ewe) of the total fatty acids. The trans-delta3 16:1 isomer, which is reported for the first time in ruminant lipids and which likely comes from the animals' feed, is present at a level of ca. 10% of the trans-16:1 acid group. Otherwise, all isomers with their ethylenic bond between positions delta4 and delta14 are observed in the three species studied, roughly showing the same relative distribution pattern. Quantitatively, the trans-16:1 isomers only represent ca. 5% of the sum of the trans-16:1 plus trans-18:1 isomers, and they appear of little importance in comparison. It is inferred from this and recent studies that some previously reported data that were established for consumption assessments dealt in fact mainly with iso-17:0 acid, which was confused with (and added to) trans-delta9 (palmitelaidic) acid; consequently, these results were large over-estimates. Regarding the cis-16:1 acids, the delta9 isomer is the prominent constituent as expected, but the second-most important isomer is the delta13 isomer. It does not appear that trans-16:1 isomers are from ruminant milk fats of great nutritional importance as compared with trans-18:1 isomeric acids. As for trans18:1 isomers, the combination Ag-TLC/GLC is a necessary procedure to quantitate trans-16:1 acids accurately and reliably. Ag-TLC allows removal of interfering branched 17:0 acids and cis-16:1 acids, and low-temperature GLC permits an accurate measurement of all individual isomers most of which with baseline resolution.


Assuntos
Queijo , Gorduras/química , Cabras , Ovinos , Animais , Bovinos , Cromatografia Gasosa , Cromatografia em Camada Fina , Gorduras na Dieta/análise , Gorduras/efeitos adversos , Gorduras/análise , Leite/química , Ácidos Palmíticos/análise , Ácidos Palmíticos/química , Estereoisomerismo
20.
Lipids ; 34(1): 39-44, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10188595

RESUMO

The aim of the present study was to assess the effect of vegetal oils obtained from Pinus pinaster and P. koraiensis seeds on plasma lipoprotein levels and apolipoprotein (apo) gene expression in rats. These oils contain two particular fatty acids of the delta5-unsaturated polymethylene-interrupted fatty acid (delta5-UPIFA) family: all-cis-5,9,12-1 8:3 (pinolenic) and/or all-cis-5,11,14-20:3 (sciadonic) acids. Rats were fed for 28 d a diet containing 5% (w/w) oil supplement. Two control diets were prepared to match the fatty acid composition of P. pinaster or P. koraiensis oils with the exception of delta5-UPIFA, which were replaced by oleic acid. Pinus pinaster seed oil decreased serum triglycerides by 30% (P < 0.02), very low density lipoprotein (VLDL)-triglycerides by 40% (P < 0.01), and VLDL-cholesterol by 33% (P < 0.03). Pinus koraiensis seed oil decreased serum triglycerides by 16% [not statistically significant (ns)] and VLDL-triglycerides by 21% (ns). Gel permeation chromatography and nondenaturating polyacrylamide gel electrophoresis showed a tendency of high density lipoprotein to shift toward larger particles in pine seed oil-supplemented rats. Finally, P. pinaster seed oil treatment was associated with a small decrease of liver apoC-III (P < 0.02) but not in apoE, apoA-I, or apoA-II mRNA levels. The levels of circulating apo were not affected by pine seed oil supplementation. In conclusion, P. pinaster seed oil has a triglyceride-lowering effect in rats, an effect that is due to a reduction in circulating VLDL.


Assuntos
Lipoproteínas/metabolismo , Óleos de Plantas/farmacologia , Animais , Apolipoproteína C-III , Apolipoproteínas C/efeitos dos fármacos , Apolipoproteínas C/genética , Peso Corporal/efeitos dos fármacos , Cromatografia em Gel , Suplementos Nutricionais , Ingestão de Alimentos/efeitos dos fármacos , Hipolipemiantes/farmacologia , Lipídeos/análise , Lipídeos/sangue , Lipídeos/química , Lipoproteínas/sangue , Lipoproteínas/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Árvores
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