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1.
Phytochemistry ; 30(6): 1749-52, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1370044

RESUMO

A new nuclease (Rn) isolated from rye nucleus was applied for the structural studies of methionine initiator transfer ribonucleic acid and ribosomal 5S rRNA from yellow lupin seeds. The enzyme shows high specificity for some regions of both RNAs. The dihydrouridine and ribothymidine loops which are supposed to be involved in the tertiary interactions of the methionine initiator tRNA were hydrolysed. The anticodon loop is not digested at all. 5S rRNA was digested in single stranded regions (loops). The cleavage pattern of the tRNA and 5S rRNA obtained with Rn enzyme, suggests not only the high specificity toward single stranded regions, but also some dependence on their tertiary structure.


Assuntos
RNA/metabolismo , Ribonucleases/metabolismo , Secale/análise , Sequência de Bases , Núcleo Celular/química , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA/química , RNA de Cadeia Dupla/metabolismo , RNA Ribossômico 5S/metabolismo , RNA de Transferência de Metionina/metabolismo , Ribonucleases/isolamento & purificação
2.
Plant Mol Biol ; 14(5): 881-8, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-1966389

RESUMO

A method is presented for the preparation of large DNA molecules from protoplasts embedded in agarose blocks of three different cereals--hexaploid bread wheat (Triticum aestivum), barley (Hordeum vulgare) and rye (Secale cereale). Pulse-field gel electrophoresis (PFGE) analysis of these DNA preparations using a contour-clamped homogeneous field (CHEF) apparatus indicated that the size of the DNA molecules was greater than 6 Mb. DNA samples prepared by this method were shown to be useful for restriction analysis using both frequent and rare cutting enzymes.


Assuntos
DNA/isolamento & purificação , Plantas/análise , DNA/química , DNA/genética , Enzimas de Restrição do DNA , Eletroforese em Gel de Ágar , Hordeum/análise , Hordeum/genética , Peso Molecular , Plantas/genética , Secale/análise , Secale/genética , Triticum/análise , Triticum/genética
3.
Carbohydr Res ; 198(1): 57-66, 1990 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-2162256

RESUMO

A water-soluble L-arabino-D-xylan, obtained from the chlorite holocellulose of de-lipidated, de-starched, and de-pectinated rye bran by ammoniacal extraction, was composed of L-Ara and D-Xyl in the molar ratio 7.8:10 and had Mw 36,500 and Mn 26,950. The backbone of the polysaccharide was shown to comprise (1----4)-linked beta-D-Xylp residues, with approximately 41% unsubstituted, approximately 33% 2- or 3-substituted, and approximately 26% disubstituted. Single alpha-L-Araf groups were attached to the xylan core; only a small proportion was 2-, 3-, or 5-linked.


Assuntos
Grão Comestível/análise , Polissacarídeos , Secale/análise , Xilanos , Sequência de Carboidratos , Cromatografia em Gel , Hidrólise , Espectroscopia de Ressonância Magnética , Metilação , Dados de Sequência Molecular , Estrutura Molecular , Oxirredução , Ácido Periódico , Solubilidade , Ácido Trifluoracético , Água
4.
Radiat Environ Biophys ; 29(3): 241-5, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2396011

RESUMO

The transfer factor (TF) for Sr-90 was studied in 10 rye fields with podzolic soils near Bremen. Values between 0.10 and 0.30 were obtained with a mean of 0.18. The TF was correlated with various soil parameters (pH, organic matter, K, Ca and P content). Negative correlations were found between TF and pH-value, Ca and P content. However, the content of organic matter in the soils was positively correlated with soil and grain activity (Bq/kg).


Assuntos
Grão Comestível/análise , Secale/análise , Poluentes Radioativos do Solo/análise , Poluentes do Solo/análise , Radioisótopos de Estrôncio/análise , Transporte Biológico , Concentração de Íons de Hidrogênio
5.
Sci Total Environ ; 84: 237-47, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2772619

RESUMO

The selenium content of hard and soft wheat, barley, oats, rye and corn grown in approximately 100 different locations of Greece has been determined fluorimetrically. The mean values +/- SD for these cereal types were 0.29 +/- 0.19, 0.21 +/- 0.12, 0.16 +/- 0.10, 0.14 +/- 0.10, 0.19 +/- 0.10 and 0.12 +/- 0.08 ppm Se (dry weight basis), respectively. Based on data for selenium in corn from 96 different locations, a geobotanic map of Greece for the selenium in soil available for uptake by plants was prepared. Macedonia, West Epirus, south-east Thessaly, north-east Sterea Hellas and the Aegean Islands produce corn deficient or low in selenium, but only sporadic selenium-deficiency diseases in animals have been observed in many of these areas, probably because the farm animals are given mixed food or they are free to graze. No areas with toxic levels of selenium in soil were found.


Assuntos
Grão Comestível/análise , Selênio/análise , Geografia , Grécia , Hordeum/análise , Secale/análise , Solo/análise , Zea mays/análise
6.
Carbohydr Res ; 187(2): 173-85, 1989 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-2743349

RESUMO

Arabinoxylans that interfere with growth of ice crystals have been purified from rye (Secale cereale L., Rosen) and two varieties of wheat (Triticum aestivum L., Genesee and Hillsdale) seed. The most active polysaccharide from each seed type was homogeneous in the sense that all the molecules were in the same size range, they contained the same sugar residues, and they reacted similarly in chemical characterization experiments. Structural studies showed that the polysaccharides consist of a xylan chain to which are attached side-chains that contain a single, terminal arabinose residue. The polysaccharides differ with respect to the number of arabinose residues. The xylose:arabinose ratios in the most active fractions from rye, Genesee wheat, and Hillsdale wheat are 1.26, 1.54, and 2.08, respectively. Gel-permeation column chromatography showed that the most active polysaccharide from each seed type has a molecular weight greater than 2 x 10(6) and that the rye polysaccharide is slightly larger than the Hillsdale wheat polysaccharide. The rye polysaccharide is a better inhibitor of ice-crystal growth than is the Hillsdale wheat polysaccharide.


Assuntos
Grão Comestível/análise , Gelo , Polissacarídeos/isolamento & purificação , Secale/análise , Triticum/análise , Xilanos/isolamento & purificação , Arabinose/análise , Arabinose/isolamento & purificação , Carboidratos/análise , Hidrólise , Raios Infravermelhos , Metilação , Peso Molecular , Polissacarídeos/análise , Polissacarídeos/efeitos da radiação , Xilanos/análise
7.
Mycopathologia ; 101(3): 157-60, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2967918

RESUMO

An investigation for the occurrence of nivalenol (NIV), deoxynivalenol (DON) and zearalenone (ZEN) in cereals (ten wheat, one rye and one corn) harvested in Canada have been carried out using a procedure, which is rapid and sensitive for Fusarium mycotoxins. NIV, DON and ZEN were detected in 4, 9 and 9 out of ten wheat samples, and their average levels in the positives were 23 ng/g, 1257 ng/g and 9 ng/g, respectively. One rye and one corn were also contaminated with a minor amount of NIV. This is the first evidence for the natural occurrence of NIV in cereals grown in Canada, though its level was far less than DON.


Assuntos
Grão Comestível/análise , Contaminação de Alimentos , Resorcinóis/análise , Sesquiterpenos/análise , Tricotecenos/análise , Zearalenona/análise , Canadá , Fusarium , Secale/análise , Triticum/análise , Zea mays/análise
8.
Plant Foods Hum Nutr ; 38(2): 175-88, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3200803

RESUMO

Barley grains (9 samples from 7 cultivars) with nitrogen contents (N) ranging from 1.45 to 4.01% of dry matter were analysed for their amino acid (AA) composition with high accuracy from six different hydrolysates per sample. AA levels in grain increased as linear functions of N with correlation coefficients close to unity. A comparison with literature data confirmed that the AA composition of any grain sample of normal barley can be predicted from its N for all phenotypes and genotypes. AAs in grain protein changed as hyperbolic functions of N which increased for Phe, Pro and Glx but more or less strongly decreased for the other AAs. By plotting AA scores against N, barley proteins were shown to be always richer than wheat and rye in Val and Phe + Tyr; sometimes richer than both other species for N less than 2 (Lys); 2.2 (Leu and Ile); 3.4 (Thr); sometimes intermediate to wheat and rye above the latter N values. They were also intermediate in sulphur AAs for N less than 1.9 and drastically poorer for N greater than 1.9. However, they were richer than both other species in Trp for N greater than 1.6. The hyperbolic variations of non-protein nitrogen and nitrogen-to-protein conversion factors were determined as a function of N and also compared with those of wheat and rye.


Assuntos
Aminoácidos/análise , Grão Comestível/análise , Hordeum/análise , Proteínas de Plantas/análise , Genótipo , Hordeum/genética , Nitrogênio/análise , Fenótipo , Secale/análise , Especificidade da Espécie , Triticum/análise
9.
Nahrung ; 32(5): 491-5, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3231240

RESUMO

A method for nearly complete extraction of the lipid fraction from wheat and rye germs was developed, and the technological parameters of the production process were specified. The resulting preparations are extracts rich in vitamin E and other biologically active components. Dermatological studies and application in the cosmetic industry have testified to the suitability of these preparations for use in cosmetic and pharmaceutical products. Owing to their high content of unsaturated fatty acids and to a natural combination of biologically active compounds, the preparations from wheat and rye germs obtained by our method on an industrial scale find increasingly wider application. The post-extraction residue free from the lipid fraction is high-value feed.


Assuntos
Grão Comestível/análise , Secale/análise , Triticum/análise , Vitaminas/isolamento & purificação , Fenômenos Químicos , Físico-Química , Lipídeos/análise , Tecnologia Farmacêutica
11.
Sci Total Environ ; 63: 111-24, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-3035714

RESUMO

Crops of wheat, rye, barley and oats were grown on fields where the contamination of the soil with radionuclides resulted exclusively from global fallout debris. After machine harvesting and milling, the concentrations of 239 + 240Pu, 241Am, 137Cs and 90Sr were determined separately in bran and flour, as well as in the soils. The concentrations of 239 + 240Pu in wheat, rye and barley flour were between 59 and 180 microBq kg-1, and in oat flour 1100 microBq kg-1. The range of concentrations of the other radionuclides for the four flours were: 241Am, 5-70 microBq kg-1, 137Cs, 260-380 mBq kg-1; 90Sr, 310-1300 mBq kg-1. The corresponding concentrations of the radionuclides were always considerably higher in the bran than in the flour, with the exception of oats. The range of this factor depends on the cereal: for 239 + 240Pu, 19-25; 241Am, 10-38; 137Cs, 4-6; and for 90Sr, 4-7. Similar differences between flour and bran were observed for stable elements, for example K, Ca and Fe. The soil-to-plant transfer factors of 239 + 240Pu for wheat, rye and barley flour were between 0.00026 and 0.00078 (oats 0.017) and for bran between 0.0048 and 0.02 (oats 0.014). For 241Am the corresponding values were somewhat lower. For the wheat, rye and barley flour the transfer factors of 137Cs were between 0.013 and 0.018 (oats 0.069) and, for the bran, between 0.08 and 0.10 (oats 0.16). The corresponding values for 90Sr were significantly higher: for flour between 0.08 and 0.14 (oats 1.2) and for bran between 0.62 and 0.93 (oats 1.5).


Assuntos
Amerício/análise , Radioisótopos de Césio/análise , Fibras na Dieta/análise , Farinha/análise , Reatores Nucleares , Guerra Nuclear , Plantas/análise , Plutônio/análise , Poluentes Radioativos do Solo/análise , Poluentes do Solo/análise , Radioisótopos de Estrôncio/análise , Grão Comestível/análise , Hordeum/análise , Secale/análise , Triticum/análise
12.
Z Lebensm Unters Forsch ; 183(1): 26-32, 1986 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-3751330

RESUMO

To recognize and determine the wheat gliadins in unheated gluten-free food for coeliac patients the immunological methods such as ELISA can be used. In heated food (above 80 degrees-90 degrees C) these methods fail wholly or in part to achieve the quantitative determination of wheat gliadin. The changes in protein patterns after heat treatment are also revealed by the RP-HPLC of wheat gliadins and some peaks appear, which are characteristic for heat treated wheat flour. Using these peaks, about 2% admixture of wheat flour (T. aestivum, T. durum) as well as of rye flour can be detected. In foods which contain more than 50% skim milk the addition of only at least 5% of these flours can be detected. The ethanolic extracts of foods were concentrated by freeze-drying prior to analysis by HPLC. The ethanol-soluble non-dialysable food components affect the quantitative determination of wheat or rye proteins by means of peak areas. Selective enrichment is a possibility. The RP-HPLC-analysis of ethanol-soluble proteins makes it possible to detect heated flours of wheat and rye (cooked, roller-dried, extrusion-cooked) in glutenfree food.


Assuntos
Gliadina/análise , Proteínas de Plantas/análise , Triticum/análise , Animais , Cromatografia Líquida de Alta Pressão , Farinha/análise , Leite/análise , Secale/análise , Temperatura
13.
Z Lebensm Unters Forsch ; 182(4): 287-93, 1986 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-3012903

RESUMO

Phytic acid in food is considered to be responsible for a reduced bioavailability of essential dietary minerals; its detrimental effects can be diminished by hydrolysis with phytase during processing. The average phytic acid content was 8.18 mg/g and 3.44 mg/g and average phytase activity was 3.7 U/g and 2.6 U/g in rye kernels and in flour (Type 997, 1.09 ash content), respectively. Phytate and Phytase were about equally distributed between the two kernel halves (cross sections). During the early stages of germination (3 days) phytase activity did not change, and phytic acid content was reduced to 67%. After milling most of the phytic acid and phytase activity were found in the bran fractions. It is concluded that substrate and enzyme are present in the same kernel structures but separate within the cells. Cooking of ground rye caused a phytate hydrolysis which was the more effective 1.) the smaller the particle sizes were, 2.) the more water was added, and 3.) the longer phytase worked at optimum temperature. Extrusion cooking of the rye whole flour at up to 100 degrees C did not influence the phytic acid level but caused a 23% reduction at 170 degrees C. Phytase activity was reduced by 80% by extrusion cooking at 80 degrees C.


Assuntos
6-Fitase/análise , Grão Comestível/análise , Ácido Fítico/análise , Secale/análise , Ração Animal/análise , Farinha/análise , Contaminação de Alimentos/análise , Tamanho da Partícula
14.
Nahrung ; 30(3-4): 275-9, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-2427950

RESUMO

The peptidase and amylase inhibitors were isolated from rye and preliminarily purified to investigate some of their properties. It was shown, that both are of albumin character despite the acetic acid solubility of the former. They are not active against the native cereal grain peptidases or amylases (rye, wheat, triticale) but the latter inhibited the animal (hog pancreas, man salivary) and bacterial (Thermamyl, NOVO) alpha-amylases. In the long-term experiments on various rye genotypes there was shown, that the peptidase inhibitor level was rather differentiated between them, but more stable as concerns particular ones. On the other hand the level differentiation of alpha-amylase inhibitor between the genotypes was rather small, but that of climate much more significant.


Assuntos
Amilases/antagonistas & inibidores , Grão Comestível/análise , Inibidores de Proteases/isolamento & purificação , Animais , Humanos , Pâncreas/enzimologia , Glândulas Salivares/enzimologia , Secale/análise , Suínos
16.
J Assoc Off Anal Chem ; 68(1): 17-9, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3980405

RESUMO

A new technique has been developed for the analysis of light filth in a high bran rye product. Compared with the official AOAC method, 44.063, the plates were much easier and less time-consuming to read microscopically (about 8 min compared with about 34 min for the AOAC method). Average recoveries for insect fragments and mouse hairs were 93.4 and 90.8%, respectively, with coefficients of variation (32 samples) of 7.7 and 7.9%, respectively. Average recoveries by the AOAC method were 87.5% for insect fragments and 62.5% for mouse hairs, with coefficients of variation (6 samples) of 7.9 and 14.1%, respectively. A ruggedness test for 7 variables in the extraction indicated that 2 variables caused significant changes in the results.


Assuntos
Pão/análise , Grão Comestível/análise , Contaminação de Alimentos/análise , Secale/análise , Animais , Cabelo , Hidrólise , Insetos , Camundongos
17.
Z Naturforsch C Biosci ; 40(1-2): 80-4, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3993182

RESUMO

The influence of 5-heptadecenylresorcinol and total rye 5-alkenylresorcinols isolated from rye grains on the red blood cell water permeability was studied using osmotic shrinkage experiments performed in 300 mM sucrose. The studied compounds induced significant increase of erythrocyte water permeability. The threshold concentration needed for the increase of water permeability was in an order of 10(-6) mol/l. The temperature dependence of the observed process showed the discontinuity which was related to the 5-alkenylresorcinol transition temperatures. It was shown also that alkenylresorcinols did not exert the biphasic action on hypotonic lysis of erythrocytes usually observed for water soluble surfactants. The specific lysine activity is postulated for the studied compounds.


Assuntos
Grão Comestível/análise , Membrana Eritrocítica/metabolismo , Resorcinóis/farmacologia , Secale/análise , Transporte Biológico/efeitos dos fármacos , Água Corporal/metabolismo , Permeabilidade da Membrana Celular , Humanos , Técnicas In Vitro , Temperatura
18.
Z Naturforsch C Biosci ; 39(11-12): 1132-6, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6531946

RESUMO

The haemolytic activity of 5-n-alk(en)ylresorcinols is temperature dependent and correlated to their transition temperatures. The values of the parameters describing the 5-n-alk(en)ylresorcinol-induced red blood cell lysis indicate strong affinity of the compounds to the membrane and their high lytic capacity. The affinity of the compounds for the membrane decrease with the increasing quantity of the molecules incorporated into the erythrocyte membrane and is much higher for saturated resorcinols than unsaturated ones. The amount of 5-n-alk(en)ylresorcinol molecules bound to the membrane at a hundred percent lysis is about eighty times and eleven times (for alkyl and alkenyl derivatives respectively) higher than at zero percent lysis. Estimated free energy of erythrocyte lysis was similar for alkyl and alkenyl derivatives of resorcinol provided the preparation of the resorcinolic suspensions above their transition temperatures.


Assuntos
Grão Comestível/análise , Hemólise/efeitos dos fármacos , Resorcinóis/farmacologia , Secale/análise , Membrana Eritrocítica/efeitos dos fármacos , Humanos , Técnicas In Vitro , Resorcinóis/isolamento & purificação , Temperatura
20.
Poult Sci ; 62(3): 472-9, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6302652

RESUMO

A study of water and Na metabolism was conducted with 24 roosters fed diets based on either corn or rye with two levels (.4 and 1.0%) of added salt. A diet containing water-extracted rye and a diet based on corn with a freeze-dried water extract of rye added at a level of 12% were also used in the study. Measurements were made on intact and colostomized roosters. In intact roosters dry matter metabolizability was depressed when rye diets were compared with corn diets. Measurements in feces from colostromized roosters fed rye as compared to those fed corn indicated that moisture, viscosity, and water holding capacity were increased and that bulk density was decreased. Diet salt level did not influence the responses regarding these parameters, but water extraction of rye completely alleviated the effects of rye on dry matter metabolizability and viscosity and partially reduced the influence of rye on fecal moisture while not altering the responses regarding water holding capacity or bulk density of feces. With the exception of feces moisture, the water extract of rye had no influence regarding these parameters. Roosters fed rye in comparison to those fed corn showed increases in water intake and excreta moisture content and decreases in urine sodium concentrations and plasma clearance of sodium. The response to rye regarding these latter parameters was dependent on diet salt level. The data indicated a reduced availability of sodium at the cellular level in rye-fed birds, which was manifest in a difference in route of excretion of sodium such that urine was the major route in corn-fed birds and feces was the major route for birds fed rye. The dietary fiber content of rye appeared to be a major factor in rye influencing sodium availability.


Assuntos
Água Corporal/metabolismo , Galinhas/metabolismo , Grão Comestível , Secale , Cloreto de Sódio/administração & dosagem , Sódio/metabolismo , Animais , Colo/metabolismo , Colostomia/veterinária , Dieta , Fibras na Dieta/metabolismo , Grão Comestível/análise , Masculino , Secale/análise , Água/análise
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