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1.
Acta bioquím. clín. latinoam ; 27(1): 39-64, mar. 1993. ilus
Artigo em Espanhol | LILACS | ID: lil-124850

RESUMO

Se presenta un resumen de los logros alcanzados durante casi 50 años en un tema fundamental del conocimiento de las características de composición acídica de aceites vegetales de producción masiva en la república Argentina. Su desarrollo, en parte coincidente con la evolución del conocimiento analítico, ha sido de utilidad a la nutrición, normalización, legislación alimentaria, tecnología, uso y contralor de aceites vegetales y de pulpa de frutos. El progreso observado en los avances de modernas técnicas de la Biotecnología tiende a una apertura en la diversificación de la producción


Assuntos
Humanos , Animais , Ácidos Graxos Essenciais/análise , Ácidos Linoleicos/análise , Ácidos Oleicos/análise , Ácidos Graxos/análise , Óleos de Plantas/análise , Óleo de Milho/análise , Óleo de Sementes de Algodão/análise , Óleo de Sementes de Algodão/efeitos adversos , Ácido Fitânico/metabolismo , Ácido Sórbico/análise , Ácido Sórbico/uso terapêutico , Arachis/análise , Compostos de Epóxi/análise , Compostos de Epóxi/classificação , Compostos de Epóxi/uso terapêutico , Frutas/análise , Helianthus/análise , Sementes/análise , Óleo de Soja/análise
2.
Acta Crystallogr C ; 47 ( Pt 4): 782-7, 1991 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-1863423

RESUMO

(1): 11 beta,17-Bis(4-bromobenzoyloxy)-9 beta-hydroxy-ent-beyerene, C34H38Br2O5, Mr = 686.5, orthorhombic, P2(1)2(1)2(1), a = 6.1686 (12), b = 14.613 (3), c = 32.935 (7) A, V = 2969 (1) A3, Z = 4, Dx = 1.536 g cm-3, lambda(Mo K alpha) = 0.71069 A, mu = 27.43 cm-1, F(000) = 1408, T = 173 K, R = 0.0347 and wR = 0.0358 for 3064 reflections [Io greater than or equal to 3 sigma(Io)]. (2): 7 beta,17-Bis(4-bromobenzoyloxy)-9 beta-hydroxy-ent-beyerene, C34H38Br2O5, Mr = 686.5, monoclinic, P2(1), a = 12.6424 (15), b = 6.8353 (12), c = 18.496 (2) A, beta = 101.901 (9) degrees, V = 1564.0 (4) A3, Z = 2, D chi = 1.458 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 26.03 cm-1, F(000) = 704, T = 173 A, R = 0.0336 and wR = 0.0361 for 4610 reflections [Io greater than or equal to 3 sigma(Io)]. (3): 17-(4-Bromobenzoyloxy)-9 beta,11 beta-epoxy-7 beta-hydroxy-ent-beyerene, C27H33BrO4, Mr = 501.5, orthorhombic, P2(1)2(1)2(1), a = 6.1315 (7), b = 18.389 (3), c = 21.109 (3) A, V = 2380.0 (6) A3, Z = 4, D chi = 1.399 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 17.38 cm-1, F(000) = 1048, T = 198 K, R = 0.0325 and wR = 0.0344 for 2292 reflections [Io greater than or equal to 3 sigma(Io)].(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Diterpenos/química , Helianthus/análise , Fenômenos Químicos , Físico-Química , Cromatografia Líquida de Alta Pressão , Cristalização , Diterpenos/isolamento & purificação , Conformação Molecular , Estrutura Molecular , Difração de Raios X
3.
Am J Clin Nutr ; 52(4): 675-81, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2206038

RESUMO

Fructans are naturally occurring plant oligosaccharides with sweetening properties. Fructans (FAs) isolated from Jerusalem artichokes (Helianthus tuberosus) were studied with respect to intestinal handling and influence on blood glucose (BG), insulin, and C-peptide responses in eight healthy subjects. The responses were compared with those for fructose ingestion. The effect of FAs added to a wheat-starch meal was also studied. Standardized breath-hydrogen excretion indicated that FAs were completely malabsorbed and, after a 20-g dose, traces of FA were detected in 24-h urine collections in one subject only. Orocecal transit times were longer for FAs than for lactulose and fructose. The BG and insulin increments were very low after FA ingestion, lower than after fructose ingestion, whereas hydrogen production was much higher. Areas under BG curves tended to be smaller when 10 g FA was added to a 50-g wheat-starch meal, but there was no apparent interference with starch absorption.


Assuntos
Glicemia/análise , Peptídeo C/sangue , Frutanos/farmacologia , Helianthus/análise , Insulina/sangue , Mucosa Intestinal/metabolismo , Polissacarídeos/farmacologia , Absorção , Adulto , Transporte Biológico/efeitos dos fármacos , Feminino , Fermentação , Frutanos/análise , Trânsito Gastrointestinal , Humanos , Hidrogênio/metabolismo , Masculino , Amido/farmacologia , Fatores de Tempo , Triticum
4.
Mol Cell Biochem ; 98(1-2): 49-56, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2266969

RESUMO

A cytosolic protein, able to facilitate intermembrane movements of phospholipids in vitro, has been purified to homogeneity from sunflower seedlings. This protein, which has the properties of a lipid-transfer protein (LTP), is also able to bind oleoyl-CoA, as shown by FPLC chromatography. This finding, in addition to previous observations suggesting that a lipid-transfer protein from spinach leaves can bind oleic acid and that oat seedlings contain a fatty acid-binding protein with similar features than lipid transfer proteins, provides a clear demonstration that plant cells contain bifunctional fatty acid/lipid transfer proteins. These proteins can play an active role in fatty acid metabolism which involves movements of oleyl-CoA between intracellular membranes.


Assuntos
Proteínas de Transporte/isolamento & purificação , Ácidos Graxos/metabolismo , Helianthus/análise , Proteínas de Neoplasias , Sementes/análise , Acil Coenzima A/metabolismo , Sequência de Aminoácidos , Antígenos de Plantas , Proteínas de Transporte/química , Cromatografia em Gel , Proteínas de Ligação a Ácido Graxo , Dados de Sequência Molecular , Fosfolipídeos/metabolismo , Proteínas de Plantas
5.
Mol Cell Biol ; 9(8): 3457-63, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2796991

RESUMO

Promoter domains required for in vivo transcriptional expression of soybean heat shock gene Gmhsp17.5-E were identified by insertion-deletion mutagenesis with transgenic expression monitored in Agrobacterium tumefaciens-incited tumors of sunflower. Removal of the TATA-distal domain from position -1175 to position -259 had little effect on overall activity. The four regions contributing to promoter activity identified by this study all map within 244 base pairs from the start of transcription. The most distal cis-acting element of major significance was located from -244 to -179 and contains a conserved TATA-dyad motif centered at -220. Sequences from -179 to -40 comprise the TATA-proximal domain and include an AT-rich region and two sites containing heat shock consensus elements (HSEs). Deletion of the HSE centered at -93 (site 2) severely reduced transcriptional activity. Heat-inducible expression was also eliminated by internal deletion of either the TATA motif or the overlapping HSEs at site 1, indicating that each of these regions is also a major determinant of promoter activity.


Assuntos
Glycine max/genética , Proteínas de Choque Térmico/genética , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Sequência de Bases , Análise Mutacional de DNA , Regulação da Expressão Gênica , Vetores Genéticos , Helianthus/análise , Dados de Sequência Molecular , Tumores de Planta/análise , Transcrição Gênica
6.
Nahrung ; 32(7): 691-700, 1988.
Artigo em Alemão | MEDLINE | ID: mdl-3231256

RESUMO

Safety evaluations of sunflower protein isolates (SPI) obtained by various processes were performed in subchronic (90-day) feeding studies using male and female rats as experimental animals. General appearance, food consumption and efficiency, haematology, kidney function and urine analysis, serum chemistry including determinations of enzyme activities, organ weights and macro- and microscopic pathology were used as criteria to disclose adverse effects. Feeding graded levels of SPI as supplements up to 75% of the total protein of the diet revealed no morphologic and functional changes attributable to toxic effects of the test product at daily intakes up to 13 g/kg body weight. The evaluations of the SPI-variants tested were similar.


Assuntos
Helianthus/análise , Proteínas de Plantas/toxicidade , Animais , Feminino , Masculino , Proteínas de Plantas/isolamento & purificação , Ratos , Ratos Endogâmicos
7.
Ann Nutr Metab ; 32(1): 1-9, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3128161

RESUMO

The effect of typical fat-modified diets on serum lipids, lipoproteins and apolipoproteins, on the intravenous fat-tolerance test and on fecal sterol excretion were observed in a group of men living at home and compared to that of their normal diets. Two 4-week-long diet periods alternated with four periods of 6 weeks' duration during which the men followed their normal dietary habits and accustomed life-styles. According to a randomized cross-over design sunflower oil and corn oil were used as the main fat sources for the fat-modified diets. Both diets lowered total cholesterol considerably acting mainly on LDL cholesterol, without affecting plasma triglycerides significantly. Apolipoprotein A-I and A-II concentrations in serum remained constant, and clearance of triglyceride-rich lipoproteins, as measured by an intravenous fat-tolerance test (Intralipid test), was not significantly affected. While changes of all measured parameters pointed in the same direction, serum total and LDL cholesterol levels were significantly lower with corn oil than with the sunflower oil. Excretion of endogenous sterols (fecal sterol balance) was higher with the fat-modified than with the normal diet. This increase in sterol excretion closely corresponded to the extent of serum cholesterol lowering.


Assuntos
Colesterol/sangue , Dieta , Gorduras na Dieta/farmacologia , Adulto , Apolipoproteína A-I , Apolipoproteína A-II , Apolipoproteínas A/sangue , Fezes/análise , Helianthus/análise , Humanos , Masculino , Óleos de Plantas/análise , Esteróis/análise , Zea mays
8.
J Nat Prod ; 50(1): 23-9, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3598595

RESUMO

From the leaves and the flowers of Helianthus glaucophyllus and Helianthus microcephalus, three new guaianolides were isolated. H. microcephalus afforded another two new guaianolides, the highly unsaturated guaianolide, the flavane, the flavone, and three flavonols. Structures of all the compounds were determined by spectral analysis.


Assuntos
Flavonoides/isolamento & purificação , Helianthus/análise , Lactonas/isolamento & purificação , Sesquiterpenos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Espectrofotometria Infravermelho
9.
CRC Crit Rev Biochem ; 20(3): 265-363, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3519077

RESUMO

This review attempts to consolidate the information on the physicochemical properties of proteins from groundnut, soybean, sesame seed, mustard seed, rapeseed, sunflower seed, cottonseed, and other oilseeds. It deals with the extraction and characterization of the oilseed proteins and describes the methods for isolation of the various protein fractions and determination of their physicochemical characteristics. Also discussed are the subunit composition of the oligomeric proteins, their hydrodynamic properties, and the effect of denaturants on these proteins. The similarity in the properties of the proteins from various oilseed materials is discussed. The review article aims to indicate the gaps in our knowledge about the physicochemical properties of oilseed proteins and suggests areas for future investigation.


Assuntos
Proteínas de Plantas , Aminoácidos/análise , Arachis/análise , Gossypium/análise , Helianthus/análise , Peso Molecular , Mostardeira/análise , Proteínas de Plantas/isolamento & purificação , Plantas Medicinais , Conformação Proteica , Sementes/análise , Glycine max/análise
10.
J Toxicol Environ Health ; 17(1): 91-100, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3005604

RESUMO

Sunflowers were grown on soil amended with 224 metric tons/ha of municipal sewage sludge from Syracuse, N.Y. The yield of sunflower seeds was reduced by 47.2% by the sludge addition. The harvested seeds contained 1.71 ppm dry weight of cadmium. Deoiled seed meal was incorporated as 25 and 50% of semipurified diet and fed to male and female Japanese quail. The concentrations of cadmium were higher in kidney, liver, muscle, and eggs of birds fed the sludge-grown seed meal as compared to control quail. Tissue concentrations of cadmium increased with increasing dietary levels of sludge-grown seed meal. No significant differences (p greater than 0.05) were observed between dietary treatments in the activity of hepatic microsomal p-nitroanisole O-demethylase or aminopyrine N-demethylase in the male birds. Additionally, no mutagenic activity, either direct or with metabolic activation, was found in quail eggs. No observable changes in tissue ultrastructure were observed under electron microscopy in any of the treatment groups. There were no significant (p greater than 0.05) differences among the dietary treatment groups in feed intake, growth rate, egg production, or egg hatchability.


Assuntos
Cádmio/análise , Fertilizantes/análise , Helianthus/análise , Óleos de Plantas , Esgotos/análise , Poluentes do Solo/análise , Animais , Cádmio/toxicidade , Coturnix , Feminino , Masculino , Óleos/análise , Óleo de Girassol
11.
Nahrung ; 30(7): 693-9, 1986.
Artigo em Alemão | MEDLINE | ID: mdl-3773982

RESUMO

Globulin isolates from native sunflower seed and industrial extraction meal obtained by extraction with different electrolyte solutions and subsequent isoelectric precipitation are relatively poor in the essential amino acids lysine, threonine, and methionine as compared to defatted seed meals. On the other hand, albumins separated by means of polyanionic complexing agents (sodium alginate and aluminium potassium sulphate) are relatively rich in these amino acids, and albumin-globulin-co-precipitates have a correspondingly balanced amino-acid composition, being also reflected by nutrition physiological values as BW, NPU, and EAA-index. As compared to seed meals protein isolates are characterized furthermore by a better protein digestibility.


Assuntos
Proteínas Alimentares/análise , Helianthus/análise , Proteínas de Plantas/análise , Aminoácidos/análise , Manipulação de Alimentos , Valor Nutritivo
12.
J Assoc Off Anal Chem ; 68(6): 1226-8, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4086447

RESUMO

The fat in vegetable foods--tree nuts, peanuts, sunflower seeds, avocado, and olives--can be determined volumetrically by acid digestion of the material and separation of the fat. The assay can be performed conveniently by using the equipment developed for fat determination of milk (Gerber method). The results agree well with those obtained by Soxhlet extraction. The advantages of using the Gerber method for vegetable foods are simplicity, speed, low operation cost, and elimination of the use of inflammable solvents.


Assuntos
Gorduras na Dieta/análise , Verduras/análise , Arachis/análise , Helianthus/análise , Nozes/análise , Glycine max/análise
13.
J Chromatogr ; 329(2): 231-46, 1985 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-4030975

RESUMO

A partial separation of nine sterol acetates and seven triterpene alcohol acetates by reversed-phase liquid chromatography is described. Good results are obtained using acetonitrile-water (90:10, v/v) as mobile phase with an UV detector at 205 nm. The variation in sterol sensitivity shows that this technique is not suitable for quantitative analyses. A combination of this technique for the fractionation of the natural sterol mixture, gas-liquid chromatography for quantitation and gas chromatography-mass spectrometry for identification is necessary for the determination of sterol compounds contained in natural products. An example of the separation, identification and quantitation of sterol acetates from sunflower seed oil is given.


Assuntos
Esteróis/análise , Triterpenos/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Helianthus/análise , Indicadores e Reagentes , Óleos/análise , Sementes/análise , Espectrofotometria Ultravioleta
15.
Z Lebensm Unters Forsch ; 179(5): 399-40, 1984 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6524080

RESUMO

High cadmium and nickel contents in sunflower kernels intended for human consumption are reported. The cadmium contents of 55 samples from North America and Europe were 0.25-0.69 mg/kg with averages from different countries of 0.32-0.54 mg/kg. The contents in kernels from bird seeds (i.e. animal feed) from China and Egypt were much lower. The cadmium content of sunflower kernels for human consumption might pose a risk to human health. Danish authorities recommend the Danish consumers do not eat large amounts of sunflower kernels for a long period of time. The nickel contents of 25 of the samples of kernels for human consumption were 2.3-5.3 mg/kg. This is comparable with that found in different kinds of nuts with high nickel contents.


Assuntos
Cádmio/análise , Helianthus/análise , Níquel/análise , Sementes/análise , Análise de Alimentos
19.
Nahrung ; 27(4): 351-69, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6877346

RESUMO

About 80% of the world protein production are of vegetable origin. More than half the vegetable protein is fed to animals, whereas merely 10 kg protein per capita are obtained from meat, milk and eggs per year. Therefore, and because of rising prices for raw materials and energy the production and the firsthand utilisation of proteinacous plants for foodstuffs are a worldwide problem. As future source of protein for human nutrition sunflower seed and oil extraction residues from sunflower seed, respectively, are of great significance. Sunflower seed does not contain anti-nutritive and toxical compounds. After crossing of species having a high oil content, the today cultivated sunflower hybrids bring seeds containing 17-22% crude protein and 30-52% oil. The cultivation also has led to a considerable reduction of the hull content. In processing of sunflower proteins colour problems occur resulting from finely ground particles of dark hulls and from polyphenolic acids which are easily oxidized and converted into brown polymerics. Essential components of the sunflower protein production are, therefore, the at least 98% dehulling before processing as well as the separation of polyphenolic acids and/or the prevention of their oxidation. In principle, the variation and combination of technological steps in pre-treating and defatting of sunflower seed, in extracting, precipitating, washing and drying of proteins, the chemical modification of proteins obtained, the interaction with neutral salts or complexing agents, and the admixture of lysine or proteins of high lysine content allow to adapt sunflower proteins to each type of application.


Assuntos
Helianthus/análise , Óleos de Plantas , Proteínas de Vegetais Comestíveis/análise , Aminoácidos/análise , Análise de Alimentos , Manipulação de Alimentos , Humanos , Óleos/análise , Óleo de Girassol
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