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1.
Nutrients ; 16(11)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38892622

RESUMEN

Breast milk (BM) plays a crucial role in providing essential fatty acids (FA) and energy for the growing infant. When the mother's own BM is not available, nutritional recommendations suggest donor milk (DM) in clinical and home practices. BM was collected from a variety of donor mothers in different lactation stages. Holder pasteurization (HoP) eliminates potential contaminants to ensure safety. FA content of BM samples from the Breast Milk Collection Center of Pécs, Hungary, were analyzed before and after HoP. HoP decreases the level of C6:0, C8:0, C14:1n-5c, C18:1n-9c, C18:3n-6c, C18:3n-3c, and C20:4n-6c in BM, while C14:0, C16:0, C18:1n-9t, C22:0, C22:1n-9c, C24:0, C24:1n-9c, and C22:6n-3c were found in elevated concentration after HoP. We did not detect time-dependent concentration changes in FAs in the first year of lactation. BM produced for girl infants contains higher C20:2n-6c levels. In the BM of mothers who delivered via cesarean section, C12:0, C15:0, C16:0, C17:0, C18:0, C18:1n-9t, C22:1n-9c levels were higher, while C18:2n-6c, C22:0, C24:0, and C22:6n-3c concentrations were lower compared to mothers who gave birth spontaneously. FAs in BM are constant during the first year of lactation. Although HoP modifies the concentration of different FAs, pasteurized DM provides essential FAs to the developing infant. Current data providing information about the FA profile of BM gives origination to supplementation guidelines.


Asunto(s)
Ácidos Grasos , Leche Humana , Pasteurización , Humanos , Leche Humana/química , Femenino , Pasteurización/métodos , Ácidos Grasos/análisis , Lactante , Adulto , Recién Nacido , Factores Sexuales , Embarazo , Lactancia , Parto Obstétrico/métodos , Hungría , Bancos de Leche Humana
2.
Physiol Plant ; 175(2): e13887, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36894826

RESUMEN

The modulation of hormone and metabolite levels by ascorbate (ASA) and hydrogen peroxide (H2 O2 ) was compared during post-germination growth in shoots of wheat. Treatment with ASA resulted in a greater reduction of growth than the addition of H2 O2 . ASA also had a larger effect on the redox state of the shoot tissues as shown by the higher ASA and glutathione (GSH) levels, lower glutathione disulfide (GSSG) content and GSSG/GSH ratio compared to the H2 O2 treatment. Apart from common responses (i.e., increase of cis-zeatin and its O-glucosides), the contents of several compounds related to cytokinin (CK) and abscisic acid (ABA) metabolism were greater after ASA application. These differences in the redox state and hormone metabolism following the two treatments may be responsible for their distinct influence on various metabolic pathways. Namely, the glycolysis and citrate cycle were inhibited by ASA and they were not affected by H2 O2 , while the amino acid metabolism was induced by ASA and repressed by H2 O2 based on the changes in the level of the related carbohydrates, organic and amino acids. The first two pathways produce reducing power, while the last one needs it; therefore ASA, as a reductant may suppress and induce them, respectively. H2 O2 as an oxidant had different effect, namely it did not alter glycolysis and citrate cycle, and inhibited the formation of amino acids.


Asunto(s)
Germinación , Peróxido de Hidrógeno , Peróxido de Hidrógeno/metabolismo , Disulfuro de Glutatión/metabolismo , Triticum/metabolismo , Ácido Ascórbico/metabolismo , Glutatión/metabolismo , Aminoácidos/metabolismo , Hormonas/metabolismo
3.
Life (Basel) ; 12(7)2022 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35888181

RESUMEN

Gestation and the neonatal period are crucial periods in infant development. Many components of breast milk, including fatty acids, play an important role in strengthening the immune system. The aim of our research was to evaluate the fatty acid profiles of milk from 69 mothers, including subjects having a normal weight, obesity, or gestational diabetes. For the analyses, we used gas chromatography (GC) with flame ionization detection (FID) and GC coupled with mass spectrometry (GC/MS). The main fatty acids found in breast milk were palmitic acid (C16:0; 26-28%), linoleic acid (C18:2; 23-28%), and α-linolenic acid linoleic acid (C18:3; 15-17%), followed by myristic acid (C14:0; 5-8%), lauric acid (C12:0; 4-6%) and stearic acid (C18:0; 4-5%). The average breakdown of fatty acids was 50% saturated, 44% polyunsaturated, and 6% monounsaturated. Breast milk samples were classified using principal component analysis and linear discriminant analysis. Results showed that milk from the two major groups of obese and normal body mass index (BMI) could be distinguished with an accuracy of 89.66%. Breast milk samples of Hungarian and Ukrainian mothers showed significant differences based on the fatty acid composition, which variations are attributable to the mothers' dietary habits.

4.
PLoS One ; 14(12): e0227271, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31891631

RESUMEN

The effects of various light intensities and spectral compositions on glutathione and amino acid metabolism were compared in wheat. Increase of light intensity (low-normal-high) was accompanied by a simultaneous increase in the shoot fresh weight, photosynthetic activity and glutathione content. These parameters were also affected by the modification of the ratios of blue, red and far-red components (referred to as blue, pink and far-red lights) compared to normal white light. The photosynthetic activity and the glutathione content decreased to 50% and the percentage of glutathione disulfide (characterising the redox state of the tissues) in the total glutathione pool doubled in far-red light. The alterations in the level and redox state of the antioxidant glutathione resulted from the effect of light on its synthesis as it could be concluded from the changes in the transcription of the related genes. Modification of the light conditions also greatly affected both the amount and the ratio of free amino acids. The total free amino acid content was greatly induced by the increase of light intensity and was greatly reduced in pink light compared to the normal intensity white light. The concentrations of most amino acids were similarly affected by the light conditions as described for the total free amino acid content but Pro, Met, Thr, ornithine and cystathionine showed unique response to light. As observed for the amino acid levels, the expression of several genes involved in their metabolism also enhanced due to increased light intensity. Interestingly, the modification of the spectrum greatly inhibited the expression of most of these genes. Correlation analysis of the investigated parameters indicates that changes in the light conditions may affect growth through the adjustment of photosynthesis and the glutathione-dependent redox state of the tissues. This process modifies the metabolism of glutathione and amino acids at transcriptional level.


Asunto(s)
Aminoácidos/metabolismo , Glutatión/metabolismo , Luz , Fotosíntesis , Triticum/metabolismo , Aminoácidos/genética , Glutatión/genética , Triticum/genética
5.
Front Plant Sci ; 9: 605, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29780400

RESUMEN

The use of light-emitting diode (LED) technology for plant cultivation under controlled environmental conditions can result in significant reductions in energy consumption. However, there is still a lack of detailed information on the lighting conditions required for optimal growth of different plant species and the effects of light intensity and spectral composition on plant metabolism and nutritional quality. In the present study, wheat plants were grown under six regimens designed to compare the effects of LED and conventional fluorescent lights on growth and development, leaf photosynthesis, thiol and amino acid metabolism as well as grain yield and flour quality of wheat. Benefits of LED light sources over fluorescent lighting were manifested in both yield and quality of wheat. Elevated light intensities made possible with LEDs increased photosynthetic activity, the number of tillers, biomass and yield. At lower light intensities, blue, green and far-red light operated antagonistically during the stem elongation period. High photosynthetic activity was achieved when at least 50% of red light was applied during cultivation. A high proportion of blue light prolonged the juvenile phase, while the shortest flowering time was achieved when the blue to red ratio was around one. Blue and far-red light affected the glutathione- and proline-dependent redox environment in leaves. LEDs, especially in Blue, Pink and Red Low Light (RedLL) regimens improved flour quality by modifying starch and protein content, dough strength and extensibility as demonstrated by the ratios of high to low molecular weight glutenins, ratios of glutenins to gliadins and gluten spread values. These results clearly show that LEDs are efficient for experimental wheat cultivation, and make it possible to optimize the growth conditions and to manipulate metabolism, yield and quality through modification of light quality and quantity.

6.
Physiol Plant ; 159(3): 264-276, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27605256

RESUMEN

Abiotic stresses induce oxidative stress, which modifies the level of several metabolites including amino acids. The redox control of free amino acid profile was monitored in wild-type and ascorbate or glutathione deficient mutant Arabidopsis thaliana plants before and after hydroponic treatment with various redox agents. Both mutations and treatments modified the size and redox state of the ascorbate (AsA) and/or glutathione (GSH) pools. The total free amino acid content was increased by AsA, GSH and H2 O2 in all three genotypes and a very large (threefold) increase was observed in the GSH-deficient pad2-1 mutant after GSH treatment compared with the untreated wild-type plants. Addition of GSH reduced the ratio of amino acids belonging to the glutamate family on a large scale and increased the relative amount of non-proteinogenic amino acids. The latter change was because of the large increase in the content of alpha-aminoadipate, an inhibitor of glutamatic acid (Glu) transport. Most of the treatments increased the proline (Pro) content, which effect was due to the activation of genes involved in Pro synthesis. Although all studied redox compounds influenced the amount of free amino acids and a mostly positive, very close (r > 0.9) correlation exists between these parameters, a special regulatory role of GSH could be presumed due to its more powerful effect. This may originate from the thiol/disulphide conversion or (de)glutathionylation of enzymes participating in the amino acid metabolism.


Asunto(s)
Aminoácidos/metabolismo , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Glutatión/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ácido Ascórbico/metabolismo , Peróxido de Hidrógeno/metabolismo , Mutación , Oxidación-Reducción , Estrés Oxidativo , Estrés Fisiológico
7.
Plant Signal Behav ; 9(1): e27598, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24398894

RESUMEN

NO has an important role in the control of plant development, growth, and the response to abiotic stress. In our recent paper it was demonstrated that NO affected the salt-induced changes in free amino acid levels in maize. (1) Since polyamines are synthesized from lysine and arginine, it was supposed that their concentrations are also influenced by NO. Cadaverine levels were increased by a NO donor and decreased by an inhibitor of NO synthesis in salt-stressed maize. These findings indicate that NO participates in the mediation of the effect of salt on cadaverine content. The coordinated changes in the NO and cadaverine levels may be involved in regulating of the response to salt stress in maize.


Asunto(s)
Cadaverina/metabolismo , Óxido Nítrico/metabolismo , Tolerancia a la Sal , Zea mays/metabolismo , Salinidad , Cloruro de Sodio , Estrés Fisiológico
8.
J Plant Physiol ; 170(11): 1020-7, 2013 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-23548311

RESUMEN

It was assumed that salt-induced redox changes affect amino acid metabolism in maize (Zea mays L.), and this influence may be modified by NO. The applied NaCl treatment reduced the fresh weight of shoots and roots. This decrease was smaller after the combined application of NaCl and an NO-donor ((Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate, DETA/NO) in the shoots, while it was greater after simultaneous treatment with NaCl and nitro-L-arginine (L-NNA, inhibitor of NO synthesis) in the roots. The quantum yield efficiency of photosystem II was not influenced by the treatments. NaCl had a significant effect on the redox environment in the leaves as it was shown by the increase in the amount of glutathione disulphide and in the redox potential of the glutathione/glutathione disulphide redox pair. This influence of NaCl was modified by DETA/NO and L-NNA. Pharmacological modification of NO levels affected salt-induced changes in both the total free amino acid content and in the free amino acid composition. NaCl alone increased the concentration of almost all amino acids which effect was strengthened by DETA/NO in the case of Pro. L-NNA treatment resulted in a significant increase in the Ala, Val, Gly and Tyr contents. The Ile, Lys and Val concentrations rose considerably after the combined application of NaCl and DETA/NO compared to NaCl treatment alone in the recovery phase. NaCl also increased the expression of several genes related to the amino acid and antioxidant metabolism, and this effect was modified by DETA/NO. In conclusion, modification of NO levels affected salt-induced, glutathione-dependent redox changes and simultaneously the free amino acid composition and the level of several free amino acids. The observed much higher Pro content in plants treated with both NaCl and DETA/NO during recovery may contribute to the protective effect of NO against salt stress.


Asunto(s)
Aminoácidos/metabolismo , Óxido Nítrico/metabolismo , Zea mays/metabolismo , Glutatión/metabolismo , Cloruro de Sodio/farmacología
9.
ScientificWorldJournal ; 2012: 216521, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22919298

RESUMEN

The effect of wheat chromosome 5A on free amino acid accumulation induced by osmotic stress was compared in chromosome 5A substitution lines with different freezing tolerance. Treatment with 15% polyethylene glycol (PEG) resulted in greater total free amino acid content even after 3 days compared to the controls. The ratio of amino acids belonging to various amino acid families differed after 3-week treatment in the control and PEG-treated plants only in the case of the freezing-sensitive substitution line. There was a transient increase with a maximum after 3 days in the amounts of several amino acids, after which their concentrations exhibited a more gradual increase. During the first days of osmotic stress the Glu, Gln, Asp, Asn, Thr, Ser, Leu, and His concentrations were greater in the tolerant substitution line than in the sensitive one, while the opposite relationship was observed at the end of the PEG treatment. The coordinated changes in the levels of individual amino acids indicated that they are involved in both the short- and long-term responses to osmotic stress. The alterations differed in the two chromosome 5A substitution lines, depending on the stress tolerance of the chromosome donor genotype.


Asunto(s)
Aminoácidos/metabolismo , Triticum/metabolismo , Presión Osmótica
10.
Plant Sci ; 180(1): 61-8, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21421348

RESUMEN

The effect of cold acclimation and abscisic acid (ABA) treatment on the free amino acid composition was compared in Chinese Spring chromosome 5A substitution lines with different levels of freezing tolerance. The total amino acid content gradually increased during the 3-week cold acclimation period, while the effect of ABA became visible only after 7 d. The ratio of members of the glutamate family increased during cold acclimation and the ratio of amino acids belonging to the aspartate family decreased. Opposite changes were observed after treatment with ABA. Consistently with these results, ABA only induced a major increase in the Asn content, while the Asp, Glu, Gln and Pro levels were greatly induced by cold. A corresponding alteration at the gene expression level was only found for Pro and Glu. With the exception of Pro, cold- or ABA-induced changes in the amino acid levelsor Pro, did not correlate with the freezing tolerance of the three genotypes examined and were not affected by chromosome 5A. Since cold acclimation induced the accumulation of most of the amino acids, while ABA had a significant effect only on Asn, the cold-induced changes in free amino acid levels were probably not mediated by ABA.


Asunto(s)
Ácido Abscísico/farmacología , Aminoácidos/metabolismo , Frío , Triticum/efectos de los fármacos , Triticum/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
11.
Amino Acids ; 38(2): 623-31, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19960214

RESUMEN

The effects of cold, osmotic stress and abscisic acid (ABA) on polyamine accumulation were compared in the moderately freezing-sensitive wheat (Triticum aestivum L.) variety Chinese Spring (CS) and in two derived chromosome 5A substitution lines, CS(T. spelta 5A) and CS(Cheyenne 5A), exhibiting lower and higher levels of freezing tolerance, respectively. When compared with the other treatments, putrescine (Put) and spermidine (Spd) levels were much greater after cold treatment, spermine (Spm) following polyethylene glycol-induced (PEG) osmotic stress and Spm and cadaverine (Cad) after ABA treatment. During 3-week cold stress, the Put concentration, first exhibited a transient increase and decrease, and then gradually increased. These alterations may be due to changes in the expression of genes encoding the enzymes of Put synthesis. The Put content was higher in the freezing-tolerant chromosome 5A substitution line than in the sensitive one after 3 weeks of cold. In contrast to cold, ABA and PEG induced a continuous decrease in the Spd level when applied for a period of 3 weeks. The Spm content, which increased after PEG and ABA addition, was twice as high as that of Put during ABA treatment at most sampling points, but this difference was lower in the case of PEG. The Cad level, induced to a great extent by ABA, was much lower when compared with that of the other polyamines. The present experiments indicate that cold, osmotic stress and ABA have different effects on polyamines, and that some of these changes are affected by chromosome 5A and correlate with the level of stress tolerance.


Asunto(s)
Ácido Abscísico/farmacología , Poliaminas/metabolismo , Triticum/fisiología , Frío , Regulación de la Expresión Génica de las Plantas , Ósmosis , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Putrescina/metabolismo , Estrés Fisiológico , Triticum/efectos de los fármacos , Triticum/genética
12.
Z Naturforsch C J Biosci ; 61(11-12): 833-9, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17294695

RESUMEN

The effect of drought stress at supraoptimal temperature on free proline and polyamine levels was compared in wild type and transgenic soybean (Glycine max cv. Ibis) plants having increased proline levels. Since glutamate and arginine are precursors of both proline and polyamines, it was assumed that the genetic manipulation of proline levels would also affect the polyamine levels. The proline and spermine concentrations increased, while the putrescine concentration generally decreased or did not change after the treatments in both genotypes. Following drought higher proline and lower spermine levels were detected in the transgenic plants compared to the wild type ones, which could be explained by the increased use of their common precursors for proline biosynthesis in the transgenic plants.


Asunto(s)
Desastres , Glycine max/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Poliaminas/metabolismo , Prolina/metabolismo , Aclimatación , Enfermedades de las Plantas , Espermina/metabolismo , Temperatura
13.
J Agric Food Chem ; 53(19): 7512-7, 2005 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-16159180

RESUMEN

The effect of simultaneous drought and heat stress on free amino acid levels was compared in wild type and transgenic soybean (Glycine max (L.) Merr cv Ibis) plants transformed with the cDNA coding for the last enzyme of Pro biosynthesis, l-Delta(1)-pyrroline-5-carboxylate reductase (EC 1.5.1.2), in sense and antisense directions. The most rapid increase in Pro content was found in the sense transformants that exhibited the least water loss, while the slowest elevation of Pro levels was detected in the antisense transformants that exhibited the greatest water loss during stress. Correspondingly, the level of the Pro precursors Glu and Arg was higher in sense transformants and lower in antisense ones compared to the wild type plants during the initial part of the stress. Interestingly, genetic manipulation of Pro levels also affected the stress-induced changes in the concentration of several other amino acids, which indicates the coordinated regulation of their metabolic pathways.


Asunto(s)
Aminoácidos/análisis , Glycine max/genética , Calor , Plantas Modificadas Genéticamente/metabolismo , Prolina/biosíntesis , Agua , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Pirrolina Carboxilato Reductasas/genética , Pirrolina Carboxilato Reductasas/metabolismo , Glycine max/crecimiento & desarrollo , Glycine max/metabolismo , delta-1-Pirrolina-5-Carboxilato Reductasa
14.
J Agric Food Chem ; 51(27): 8055-60, 2003 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-14690396

RESUMEN

Principal component analysis (PCA) and linear discriminant analysis (LDA) were used to classify 187 Hungarian white and red wines according to wine-making technology, geographic origin (wine-making region), grape variety, and year of vintage based on free amino acid and biogenic amine contents. Determination of free amino acids and biogenic amines was accomplished by ion-exchange chromatography. Six principal components accounted for >77% of the total variance in the data. The plots of component loadings showed significant groupings of free amino acids and biogenic amines. The component scores grouped according to wines made by different wine-making technologies. Using LDA the variables with a major discriminant capacity were determined. Almost complete classification (94.7%) was achieved concerning both white and red wines and wines made by different wine-making technologies. The results of differentiation between white wines according to geographic origin, grape variety, and year of vintage were 70.8, 62.4, and 73.5%, respectively. The same numbers for red wines according to geographic origin, grape variety, and year of vintage were 64.9, 71.6, and 82.4%, respectively.


Asunto(s)
Aminoácidos/análisis , Aminas Biogénicas/análisis , Vino/análisis , Cromatografía por Intercambio Iónico , Análisis Discriminante , Manipulación de Alimentos/métodos , Factores de Tiempo , Vitis/química , Vitis/clasificación , Vino/clasificación
15.
J Agric Food Chem ; 50(13): 3768-74, 2002 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-12059158

RESUMEN

Biogenic amines, polyphenols, and resveratrol were analyzed quantitatively in 25 different Hungarian wines from the same wine-making region, harvest of 1998. Polyphenols were determined according to a spectrophotometric method, whereas other substrates were analyzed using overpressured-layer chromatography (OPLC). Principal component analyses (PCA) were performed on data matrices consisting of substrates (columns) and different sorts of wines (rows) from the region of Pécs (southern Hungary). It was found that four (unrotated) principal components account for >80% of the total variance in the data. The plots of component loadings showed significant groupings for concentrations of biogenic amines (and polyphenols). Similarly, the component scores grouped according to the different sorts of wines. The loading plots reveal that there is no need to measure all of the variables to achieve the same characterization. It is enough to measure one variable per group. Naturally, this conclusion is valid only within the limits of the present study; wines from other regions may behave differently.


Asunto(s)
Aminas Biogénicas/análisis , Flavonoides , Fenoles/análisis , Polímeros/análisis , Vino/análisis , Cromatografía/métodos , Hungría , Polifenoles , Resveratrol , Espectrofotometría , Estilbenos/análisis
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