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1.
Science ; 172(3985): 864-5, 1971 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-17792945

RESUMO

Gas chromatographic and mass spectrometric analyses on selected lipid fractions revealed for the first time the presence of ethyl esters of long-chain fatty acids as biological products. Ethyl esters of oleic, palmitic, and stearic acids were detected in relative concentrations of 21.2, 2.4, and 1.5 percent, respectively, of the total methyl and ethyl ester fraction. Both saturated and unsaturated ethyl esters contain pronounced mass spectral fragments at a mass-to-charge ratio of 88.

2.
Science ; 175(4022): 623-4, 1972 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-17808799

RESUMO

Tobacco tissue cultures grown in contact with lunar material from Apollo 12, for a 12-week period, resulted in fluctuations of both the relative and absolute concentrations of endogenous sterols and fatty acids. The experimental tissues contained higher concentrations of sterols than the controls did. The ratio of campesterol to stigmasterol was greater than 1 in control tissues, but less than 1 in the experimental tissues after 3 weeks. High relative concentrations (17.1 to 22.2 percent) of an unidentified compound or compounds were found only in control tissues that were 3 to 9 weeks of age.

3.
Mol Immunol ; 19(11): 1491-8, 1982 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6897850

RESUMO

Multilamellar lipid vesicles (MLV) composed of egg yolk lecithin (EYL) suppressed the response of bovine peripheral blood lymphocytes (BPBL) to phytohemagglutinin (PHA). EYL contains 18:1 and 18:2 as the major unsaturated phospholipids. Dioleoyllecithin (DOL; cis 9) MLV did not suppress BPBL blastogenesis. Dilinoeyllecithin (DLL; cis, cis 9, 12) MLV suppressed BPBL blastogenesis. The suppressive effect could be reversed by increasing the MLV DML concentration. The addition of alpha-tocopherol (alpha-T) at 10 mole% into MLV containing DLL reversed blastogenic suppression of BPBL. MLV composed of mixed saturated phospholipids (dimyristoyllecithin and dipalmitoyllecithin) and alpha-T enhanced the BPBL blastogenic response to PHA. BPBL incubated with varying PHA concentrations (11.82-375 mg/ml) and a constant concentration (2 mumoles/ml) of MLV composed of EYL remained suppressed either when PHA and MLV were added simultaneously or when MLV were incubated for 1 hr prior to the addition of PHA. This suggests that alpha-T may act as an immunomodulator in the blastogenic response to PHA. Results suggest that alpha-T reversion of EYL suppression of BPBL blastogenesis may be due to interactions of alpha-T with unsaturated acyl chains in EYL phospholipids.


Assuntos
Ativação Linfocitária/efeitos dos fármacos , Linfócitos/imunologia , Fosfolipídeos/farmacologia , Vitamina E/farmacologia , Animais , Bovinos , Dimiristoilfosfatidilcolina , Relação Dose-Resposta a Droga , Lipossomos , Fosfatidilcolinas/farmacologia , Fito-Hemaglutininas/farmacologia , Surfactantes Pulmonares/farmacologia
4.
Am J Clin Nutr ; 44(6): 816-24, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3466523

RESUMO

The essential fatty acid deficient (EFAD) chicken was evaluated as a model for cystic fibrosis (CF). Three semipurified diets--(I) 1% hydrogenated coconut oil (HCO), (II) 10% soybean oil + 1% HCO, and (III) 11% HCO--were fed to chickens from hatching to 5, 8, or 11 wk. Groups I and III exhibited poor weight gain and abnormal serum fatty acid patterns characteristic of EFAD. Production of prostaglandin F2 alpha, thromboxane B2, 6-keto-prostaglandin F1 alpha, and prostaglandin E in lung was significantly reduced at 5, 8, and 11 wk in both EFAD groups. Histopathologic examination revealed increased peribronchiolitis in group I compared with II. Incidence of pulmonary lesions in group III was intermediate. These data support the theory that essential fatty acids are necessary to maintain proper lung function. In this respect, the chicken is a good model for studying the relationship between EFAD and pulmonary disease in CF patients.


Assuntos
Galinhas/metabolismo , Fibrose Cística/metabolismo , Ácidos Graxos Essenciais/deficiência , 6-Cetoprostaglandina F1 alfa/biossíntese , Animais , Galinhas/crescimento & desenvolvimento , Fibrose Cística/patologia , Dinoprosta , Modelos Animais de Doenças , Ácidos Graxos/sangue , Pulmão/metabolismo , Pulmão/patologia , Prostaglandinas E/biossíntese , Prostaglandinas F/biossíntese , Tromboxano B2/biossíntese
5.
Am J Clin Nutr ; 43(4): 530-7, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3962906

RESUMO

To determine the amount of isomeric fatty acids in the diets of a segment of the American population, daily food intake was collected, using the duplicate portion method, from eight healthy white adolescent girls for 7 days. The fifty-six diets were analyzed for fatty acids by gas-liquid chromatography. The amount of trans isomers of octadecenoic acid (18:1t) in the diets of the eight girls ranged from 3.5 to 8.2% of total fatty acids with an average of 5.3%. Other trans fatty acids included trans isomers of 14:1 and 16:1, and cis,trans and trans,cis isomers of 18:2. No measurable amounts of trans,trans octadecadienoic acid (18:2tt) were found in the diets of the girls. The total trans fatty acid content of the diets averaged 6.5% of total fatty acids. The daily consumption of total trans fatty acids by the eight girls over a 1 wk period averaged 3.1 g, with 2.6 g of this being 18:1t.


Assuntos
Gorduras na Dieta/análise , Ácidos Graxos/análise , Adolescente , Estatura , Peso Corporal , Criança , Cromatografia Gasosa , Inquéritos sobre Dietas , Ingestão de Energia , Feminino , Humanos , Isomerismo
6.
Am J Clin Nutr ; 39(5): 778-86, 1984 May.
Artigo em Inglês | MEDLINE | ID: mdl-6711479

RESUMO

To study the effects of hydrogenated fat in the maternal diet on lipid composition and prostaglandin content of human milk, eight nursing mothers, 2 months postpartum, were provided with two 5-day diets in a cross-over design with an intervening 2-day period. Diets for the two periods were identical except that sources of hydrogenated fat were used in the meals for one period and nonhydrogenated fat in the other. Trans-isomers of octadecenoic acid (18:lt) comprised 11.8% of the total fatty acids in the hydrogenated fat diet compared with 1.0% in the nonhydrogenated fat diet. The 18:lt content of milk collected daily during hydrogenated fat consumption was 6.5% of the total fatty acids and was significantly higher (p less than 0.01) than the 18:lt content (1.8% of the total fatty acids) of milk collected during nonhydrogenated fat consumption. The amount of 18:lt in the milk was positively correlated (r = 0.909) with the 18:lt content in the previous day's diet. Although detectable concentrations of prostaglandins PGF2 alpha and PGE were found in human milk, their concentrations were not affected by hydrogenated fat in the maternal diet.


Assuntos
Gorduras na Dieta/metabolismo , Leite Humano/análise , Adulto , Ácidos Graxos/análise , Feminino , Humanos , Lactação , Gravidez , Prostaglandinas E/análise , Prostaglandinas F/análise , Estereoisomerismo
7.
Mar Biotechnol (NY) ; 4(6): 604-11, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14961235

RESUMO

The effect of rainbow trout growth hormone complementary DNA on body shape, dress-out yield, and body composition were assessed in the F1 and F2 generations of transgenic common carp (Cyprinus carpio). All measurements were compared with those for nontransgenic full-sibling common carp in their respective families, and the fish were communally evaluated in earthen ponds. The body weight and length were highly correlated (P <0.01) in both genotypes in all the families. Head morphometrics were negatively correlated (P <0.05) to weight and length of the fish. Various head, body, and caudal traits grew disproportionately faster in transgenic fish in both generations. The altered body shape of transgenic fish resulted in improved dressing percentage in the F2 generation. The carcass composition of transgenic muscle had a lower percentage of (P <0.01) moisture and lipids and higher (P <0.01) percentage of protein in both generations. Six of the 18 amino acids analyzed in F1 transgenic common carp muscle were higher F1 (P <0.05) than the control genotype; however, amino acid ratios were minimally changed. Also, the fatty acid profiles of both genotypes were minimally altered. Higher histidine and lysine ratios in the diet are recommended for maximum growth and health of transgenic common carp in intensive culture systems on the basis of essential amino acid ratios.

8.
Lipids ; 12(4): 398-401, 1977 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-853881

RESUMO

The hydrocarbons, fatty acids, and sterols of Cronartium fusiforme basidiospores were examined by gas chromatography and mass spectrometry. Trace quantities of aliphatic hydrocarbons were detected, but these were probably not fungal products. Principal nonsubstituted fatty acids were palmitic (11.7%), linoleic (17.2%), and linolenic (16.1%) acids; the predominant acid was 9,10-cis-epoxyocta-decanoic acid (40.7%). Four sterols were detected, three of which were identified as stigmast-7-enol (57.6%), stigmasta-5, 7-dienol (22.7%), and ergost-7-enol (16.0%). The fourth sterol (4%) is a C28 diene. Lipids of the aeciospores and basidiospores of C. fusiforme are compared.


Assuntos
Basidiomycota/análise , Ácidos Graxos/análise , Fitosteróis/análise , Espectrometria de Massas , Esporos Fúngicos/análise
9.
Lipids ; 32(12): 1309-16, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9438242

RESUMO

The sterol composition of 42 fungal species representing six of the eight orders of the Zygomycota was determined using gas-liquid chromatography-mass spectrometry to assess whether the distribution of major sterols in this phylum has taxonomic or phylogenetic relevance. Ergosterol, 22-dihydroergosterol, 24-methyl cholesterol, cholesterol, and desmosterol were detected as the major sterols among the species studied. Ergosterol was the major sterol of the Dimargaritales, Zoopagales, and 13 of the 14 Mucorales families included in this study. Desmosterol appeared to be the characteristic sterol of the Mortierellaceae (Mucorales), 24-Methyl cholesterol was the major sterol of the Entomophthorales genera Entomophthora, Conidiobolus and Basidiobolus, but cholesterol was the sole sterol detected in Delacroixia coronatus. The Kickxellales species analyzed in this study were characterized by 22-dihydroergosterol as the major sterol. These results suggest that certain orders of the Zygomycota may be distinguished on the basis of major sterol. Also, if sterol structure has phylogenetic implications, then orders might be arranged in the order Kickxellales (C28 delta 5,7)-->Dimargaritales, Zoopagales and Mucorales (C28 delta 5,7,22) on the basis of evolution of the predominant and presumably most competent sterol, ergosterol. Although the Entomophthorales would be expected to be more primitive than the above orders based on the predominance of C28 delta 5, it is not apparent from these data that members of the Zygomycota with ergosterol or its precursors as major sterols evolved from this taxon or the Chytridiomycota.


Assuntos
Fungos/química , Filogenia , Fitosteróis , Esteróis/análise , Colesterol/análogos & derivados , Colesterol/análise , Desmosterol/análise , Ergosterol/análogos & derivados , Ergosterol/análise , Evolução Molecular , Fungos/classificação , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Esteróis/química
10.
Lipids ; 32(8): 839-45, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9270975

RESUMO

As a representative of a genus with species considered to be potential commercial producers of the nutritionally important polyunsaturated fatty acid docosahexaenoic acid (DHA), Thraustochytrium sp. ATCC 26185 was investigated to determine its potential for DHA production and lipid composition. Cells from liquid shake cultures contained 32% (w/w) lipid, 18% of which was nonsaponifiable lipid. The major saturated fatty acids (14:0 and 16:0) comprised up to 59% of the total fatty acids, and DHA was up to 25% after 6 d incubation. Squalene represented 63% of the nonsaponifiable lipid, and cholesterol composed 41% of the total sterols. The phospholipids expected for eucaryotic microbes were detected with phosphatidylcholine as the major phospholipid at 76% of the total. The ultrastructure of this species was similar to other Thraustochytrium species except that the cells did not have surface scales and they contained unusual membrane-like structures that appeared to be associated with oil formation.


Assuntos
Fungos/química , Fungos/ultraestrutura , Lipídeos/química , Cromatografia Gasosa , Ácidos Docosa-Hexaenoicos/análise , Ácidos Graxos/análise , Fungos/crescimento & desenvolvimento , Lipídeos/análise , Microscopia Eletrônica , Fosfolipídeos/análise , Esqualeno/análise , Esteróis/análise
14.
J Gen Microbiol ; 137(8): 1825-30, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1955868

RESUMO

Several strains of species of the fungal genus Pythium, and of Phytophthora cinnamomi, were screened for content of the polyunsaturated fatty acids (PUFAs) arachidonic acid (AA) and eicosapentaenoic acid (EPA). The aim of the investigation was to establish alternative sources of these PUFAs, which are of importance in human nutrition. As a relatively prolific producer of EPA and AA, P. ultimum strain #144 was selected for a study of conditions that enhance their production over baseline levels that are present in the fungus when cultured for 6 d at 25 degrees C with rotary shaking (120 r.p.m.) in Vogel's medium containing sucrose as the carbon substrate. The levels of AA and EPA under these conditions were 133 +/- 27 and 138 +/- 25 mg l-1 (n = 5), respectively. Maximal production of these fatty acids was accomplished by the following sequence of steps. (1) Incubate the cultures for 6 d after inoculation under the conditions described above. Then (2) add glucose to the cultures (2%, w/v, final concentration) and incubate for a further 6 d at 13 degrees C. Under these conditions, the AA content of the mycelium was 205% higher than baseline levels and the EPA content was 198% higher. (3) Allow the cultures to remain stationary for 10 d which increases the AA content to 253% above baseline levels and the EPA content by 236%. Using such a procedure, 322 mg AA l-1 and 383 mg EPA 1-1 were produced.


Assuntos
Ácido Araquidônico/biossíntese , Ácido Eicosapentaenoico/biossíntese , Pythium/metabolismo , Ácido Araquidônico/isolamento & purificação , Meios de Cultura , Ácido Eicosapentaenoico/isolamento & purificação , Glucose/farmacologia , Micologia/métodos , Pythium/crescimento & desenvolvimento , Temperatura
15.
Can J Microbiol ; 42(12): 1241-7, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8989862

RESUMO

Isocitrate dehydrogenase is considered to be one of the key regulatory enzymes in the conversion of glucose into fatty acids by oleaginous microorganisms. A dual coenzyme-specific isocitrate dehydrogenase (EC 1.1.1.41) (IDH) was isolated from the primitive fungus Pythium ultimum and purified by 211-fold by sequential ion-exchange, affinity, and gel filtration chromatographies. Specific activity of the partially purified enzyme was 76.2 mumol/(min.mg protein) with NAD+ and 40% less active with NADP+. Optimum pH for activity was 8.5-9.5. K(m) values for threo-D-isocitrate and NAD+ were 0.031 and 0.55 mM, respectively. The estimated molecular mass of the IDH was 96 kDa under nondenaturing conditions and 48 kDa under denaturing conditions, suggesting that the enzyme is composed of two subunits of the same size. The enzyme was relatively stable up to 55 degrees C, but no activity was detected after exposure to 65 degrees C for 15 min. Mg2+ or Mn2+ were required for activity.


Assuntos
Isocitrato Desidrogenase/metabolismo , NADP/metabolismo , NAD/metabolismo , Pythium/enzimologia , Cátions Bivalentes/farmacologia , Cátions Monovalentes/farmacologia , Estabilidade Enzimática , Temperatura Alta , Concentração de Íons de Hidrogênio , Isocitrato Desidrogenase/efeitos dos fármacos , Isocitrato Desidrogenase/isolamento & purificação , Cinética , Lipídeos/biossíntese , Peso Molecular , Estereoisomerismo
16.
J Bacteriol ; 103(3): 536-40, 1970 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-5474875

RESUMO

The lipids of Rhizopus arrhizus Fischer mycelia and sporangiospores were extracted, isolated, and separated by thin-layer, liquid, and gas chromatography. Structural confirmations of the compounds were made by a gas chromatographmass spectrometer combination. The n-heptane fraction contained squalene (1%) as a major hydrocarbon constituent. Other major lipid classes detected were free fatty acids, naturally occurring methyl esters of fatty acids, triglycerides, sterols, and polar lipids. The polar lipids (44.4%) were found in the highest concentrations, and the triglycerides (22.1%), sterols (16.7%), and free fatty acids (11.7%) were present in lesser concentrations. This is the first report of naturally occuring methyl esters of long-chain fatty acids being present in fungal mycelium. There appears to be a preference for incorporation of unsaturated acids into the complex lipids, with the exception of the triglycerides. The major saturated fatty acids in the mycelium were palmitic (C(16)) and arachidic (C(20)), whereas the major unsaturated acids were oleic (C(18:1)) and linoleic (C(18:2)), respectively.


Assuntos
Lipídeos/análise , Rhizopus/análise , Alcanos/análise , Cromatografia Gasosa , Cromatografia em Camada Fina , Ésteres/análise , Ácidos Graxos/análise , Ácidos Graxos não Esterificados/análise , Lipídeos/isolamento & purificação , Análise Espectral , Esporos/análise , Esteróis/análise , Triglicerídeos/análise
17.
Can J Microbiol ; 25(12): 1481-3, 1979 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-394825

RESUMO

The sterol and fatty acid content of mycelium from germinating basidiospores of Cronartium fusiforme was determined. The mycelium contained stigmast-7-enol, fungisterol, and possibly stigmasta-5,7-dienol. No ergosterol was detected. The mycelium contained the expected fatty acids and low relative proportions of 9,10-epoxyoctadecanoic acid. The absence of ergosterol, and presence of the epoxy C18 acid and sterols typical of certain rust spores may be used for a relatively rapid confirmation of rust fungi in culture. Based on these chemical criteria, yeast-like cells isolated from the cultures of germinating basidiospores appear not to be C. fusiforme.


Assuntos
Basidiomycota/análise , Ácidos Graxos/análise , Técnicas Microbiológicas , Esteróis/análise , Basidiomycota/classificação , Basidiomycota/crescimento & desenvolvimento
18.
Biochem Biophys Res Commun ; 175(2): 500-6, 1991 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-1850244

RESUMO

A cAMP-independent protamine kinase has been purified from extracts of the yeast Candida lipolytica by ion-exchange and affinity chromatography. Two subunits with apparent Mr's of 52,000 and 36,000 were resolved by SDS-PAGE. The purified kinase exhibited about 20% activity with casein and histone Type VII-S as substrates relative to protamine. The enzyme was inactive against other protein substrates tested, and was essentially insensitive to AMP, cAMP, cGMP up to 0.2 mM, the polyamines spermine and spermidine up to 1 mM, N-ethylmaleimide (5 mM), 2-mercaptoethanol (20 mM), or dithiothreitol (2 mM), and several cations like Zn2+, N1+, or Co2+ at 0.1 mM each. Ca2+ at 3 mM inhibited protamine kinase activity by 50%, which was reversed by EGTA.


Assuntos
Candida/enzimologia , Proteínas Quinases/metabolismo , Cálcio/farmacologia , AMP Cíclico/fisiologia , Substâncias Macromoleculares , Peso Molecular , Protamina Quinase , Protaminas/metabolismo , Inibidores de Proteínas Quinases , Proteínas Quinases/química , Especificidade por Substrato
19.
J Nutr ; 117(2): 232-41, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3470441

RESUMO

The effects of seven levels of dietary linoleic acid (18:2), with and without trans-octadecenoic acid (18:1t), on the fatty acid composition and prostaglandin content of milk were investigated in lactating rat dams. At parturition, 14 groups of 4 rats each were fed diets containing 20% fat, with mixtures of coconut and safflower oils providing seven concentrations of 18:2 ranging from 3.6 +/- 0.5 to 44.5 + 2.3% of total fatty acids. Hydrogenated soybean oil was added such that 18:1t comprised 10.3 +/- 0.3% of total fatty acids. Milk samples were collected on day 12 postpartum for prostaglandin analyses and on day 16 for fatty acid analyses. The relationship of dietary 18:2 to milk 18:2 was linear (r = 0.98; P = 0.0001), with milk 18:2 ranging from 2.6 +/- 0.1% of total fatty acids at the lowest level of dietary 18:2 to 27.9 +/- 1.6% at the highest. Milk 18:1t was highly correlated (r = 0.99; P = 0.0001) with the amount of dietary 18:1t. In rats fed hydrogenated fat, milk 18:1t averaged 7.0 +/- 0.2% of total fatty acids. Transfer from diet to milk was 46.4 +/- 4.2% for 18:2 and 37.5 +/- 1.7% for 18:1t. Mean concentrations of prostaglandin F2 alpha and E in rat milk were 269 +/- 16 pg/mL and 477 +/- 24 pg/mL respectively. There were no significant differences in the concentrations of either prostaglandin relative to 18:1t consumption at any level of 18:2.


Assuntos
Gorduras na Dieta/farmacologia , Ácidos Graxos/metabolismo , Ácidos Linoleicos/farmacologia , Leite/metabolismo , Ácidos Oleicos/farmacologia , Prostaglandinas/metabolismo , Animais , Gorduras na Dieta/administração & dosagem , Dinoprosta , Feminino , Lactação/metabolismo , Ácido Linoleico , Ácidos Linoleicos/administração & dosagem , Leite/efeitos dos fármacos , Gravidez , Prostaglandinas E/metabolismo , Prostaglandinas F/metabolismo , Ratos
20.
J Nutr ; 117(7): 1197-206, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3612299

RESUMO

This study was conducted to determine if dietary omega-3 polyunsaturated fatty acids could modulate lung eicosanoid production. Three groups of chickens were depleted of essential fatty acids by feeding diets containing 1% hydrogenated coconut oil from hatching to 8 wk, followed by repletion for 3 wk with diets containing soybean oil (SBO) and linseed oil (LSO) separately or in combination. The ratio of linoleic acid (18:2 omega 6) to linolenic acid (18:3 omega 3) was 7.48, 1.17 or 0.32, respectively, for diets containing 10% SBO, 5% SBO/5% LSO or 10% LSO. A 10% SBO diet fed for 11 wk served as the control. Production of prostaglandin F2 alpha, prostaglandin E, thromboxane B2 and 6-keto-prostaglandin F1 alpha by incubated lung was lower in birds fed linseed oil, with total prostanoid production being 95, 42 and 22% of control values for the three dietary treatments, respectively. The ratio of arachidonic acid (20:4 omega 6) to linoleic acid (18:2 omega 6) in serum phospholipids followed a similar pattern for the three treatments, with values of 0.96, 0.52 and 0.21. Thus, production of lung prostanoids of the 2-series could be modulated by varying the dietary omega 6/omega 3 ratio. This effect may be due in part to depression of phospholipid arachidonate, the precursor of 2-series eicosanoids.


Assuntos
Galinhas/metabolismo , Gorduras Insaturadas na Dieta/metabolismo , Ácidos Eicosanoicos/metabolismo , Ácidos Graxos Insaturados/metabolismo , Pulmão/metabolismo , Óleos de Plantas , Animais , Óleo de Coco , Cocos , Gorduras na Dieta , Gorduras Insaturadas na Dieta/administração & dosagem , Gorduras Insaturadas na Dieta/análise , Ácidos Eicosanoicos/análise , Ácidos Graxos Insaturados/administração & dosagem , Ácidos Graxos Insaturados/análise , Ácidos Graxos Insaturados/deficiência , Óleo de Semente do Linho , Lipídeos/análise , Pulmão/análise , Óleo de Soja , Fatores de Tempo
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