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1.
Dokl Biol Sci ; 499(1): 109-112, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34462838

RESUMO

Biotechnological methods are an essential component of plant genetic resources investigation that allow both to preserve a rare natural plant and useful selection genotypes, especially essential oil bearing plants used in medicine, perfume, food, etc. In the clonal micropropagation in vitro, the key moment is to retain genetic stability of in vitro material. It is considered that plant regeneration in vitro from meristem or vegetative buds gives identical clones, but the effect of the medium growth regulators on the genetic stability of in vitro plant material is discussed. Therefore, the objective of our work was to evaluate the genetic similarity of ex situ and in vitro plants. Investigation was performed on Hyssopus officinalis L. cv. Nikitskiy Beliy (NBG selection). Regeneration from the shoot single-node segments on the modified Murashige and Skoog culture medium (MS) supplemented with 6-benzylaminopurine (BAP) in concentration 0.3-0.9 mg/L and 0.1 mg/L Indole-3-butyric acid (IBA) was carried out. It was established, that application of 0.5 mg/L BAP was sufficient for the organ formation and development without morphological deviations. Genetic analysis based on RAPD and ISSR-PCR had shown full genetic similarity of the investigated ex situ and in vitro plants.


Assuntos
Hyssopus , Reguladores de Crescimento de Plantas , Brotos de Planta/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico
2.
Environ Pollut ; 274: 116588, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33548668

RESUMO

Vast areas of Europe were contaminated by the fallout of 137Cs and other radionuclides, as a result of the Chernobyl accident in 1986. The post-fallout redistribution of Chernobyl-derived 137Cs was associated with erosion and sediment transport processes within the fluvial system. Bottom sediments from lakes and reservoirs can provide a valuable source of information regarding the post-fallout redistribution and fate of 137Cs released by the Chernobyl accident. A detailed investigation of sediment-associated 137Cs in the bottom sediments of a reservoir in a Chernobyl-affected area in Central Russia has been undertaken. A new approach, based on the vertical distribution of 137Cs activity concentrations in the reservoir bottom sediment makes it possible to separate the initially deposited bottom sediment, where the 137Cs activity reflects the direct fallout of Chernobyl-derived 137Cs to the reservoir surface and its subsequent incorporation into sediment deposited immediately after the accident, from the sediment mobilized from the catchment deposited subsequently. The deposits representing direct fallout from the atmosphere was termed the "Chernobyl peak". Its shape can be described by a diffusion equation and it can be distinguished from the remaining catchment-derived 137Cs associated with sediment accumulated with sediments during the post-Chernobyl period. The 137Cs depth distribution above the "Chernobyl peak" was used to provide a record of changes in the concentration of sediment-associated 137Cs transported from the upstream catchment during the post-Chernobyl period. It was found that the 137Cs activity concentration in the sediment deposited in the reservoir progressively decreased during the 30-year period after the accident due to a reduction in the contribution of sediment eroded from the arable land in the catchment. This reflects a reduction in both the area of cultivated land area and the reduced incidence of surface runoff from the slopes during spring snowmelt due to climate warming.


Assuntos
Acidente Nuclear de Chernobyl , Monitoramento de Radiação , Cinza Radioativa , Poluentes Radioativos da Água , Radioisótopos de Césio/análise , Europa (Continente) , Sedimentos Geológicos , Cinza Radioativa/análise , Federação Russa , Poluentes Radioativos da Água/análise
3.
Vopr Pitan ; 88(2): 73-82, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31233691

RESUMO

Knowledge about food composition is necessary both for specialists to assess the state of nutrition of the population and develop recommendations on nutrition, as well as for consumers to organize healthy individual nutrition. Russian Union of Juice Producers together with research organizations is working to systematize and expand knowledge about the composition of juices, as one of the important elements in the structure of human nutrition. Aim is to establish the nutrient profile of pineapple juice. Material and methods. Data analysis of reference books and scientific publications, conducting physic-chemical studies of industrially produced pineapple juice. Results and discussion. The nutrient profile shows the content of more than 30 nutritive and bioactive compounds in pineapple juice. Sugars in pineapple juice are represented by glucose, fructose and sucrose in an average ratio of 1:1:1.6, organic acids are mainly citric and L-malic acids, while the content of citric acid is 2-4 times higher than that of L-malic. A portion of industrially produced pineapple juice on average contains 10% of the daily human requirement for potassium and magnesium, about 15% for copper, 60-70% for vitamin C. The content of vitamin B1 and folate is about 7% of daily recommended level, vitamin B6 - about 12%. Pineapple juice is a source of manganese - a portion contains more than 100% of the adequate level of daily consumption of this trace element. Polyphenolic compounds are mainly represented by hydroxycinnamic acids, among which synaptic acid and its derivatives and p-coumaroyl chinic acid predominate (45-80% of all hydroxycinnamic acids in total). The content of hydroxycinnamic acids per serving averages 30% of the adequate level of their daily intake. Pineapple juice shows proteolytic activity (about 1 pe per 1 g of dry matter), which is associated with the content of the complex of proteolytic enzymes in pineapples. Conclusion. The most significant from the point of view of providing a human body with micronutrients and minor bioactive compounds for pineapple juice are manganese, vitamin C, hydroxycinnamic acids, copper, potassium, magnesium, and B vitamins (B1, B6, folates).


Assuntos
Ananas/química , Sucos de Frutas e Vegetais/análise , Valor Nutritivo , Ácido Cítrico/análise , Carboidratos da Dieta/análise , Humanos , Malatos/análise , Micronutrientes/análise
4.
Vopr Pitan ; 87(2): 53-64, 2018.
Artigo em Russo | MEDLINE | ID: mdl-30592869

RESUMO

Every juice contains a unique set of nutritive and biologically active substances, exhibiting the properties of the named fruit or vegetable. To characterize the nutritional profile of tomato juice, the literature data (including official reference books) and the results of studies of domestic industrially produced tomato juices conducted by the Russian Juice Producers Union (RSPS) and its members have been analyzed and summarized. From the point of view of providing a man with micronutrients and minor biologically active substances, tomato juice is a significant source of antioxidants - carotenoids and vitamin E, as well as several minerals and trace elements. The amount of lycopene in a glass of tomato juice (200-250 ml) completely satisfies or exceeds the recommended daily intake of this carotenoid; the level of ß-carotene in the same volume of juice provides about 20% of the recommended daily intake of vitamin A; potassium and copper - 12-15%, magnesium, iron, manganese and phosphorus - about 5%. Tomato juice is a source of dietary fiber, including soluble dietary fiber (pectin). A glass of tomato juice contains about 12% of the recommended daily intake of pectins and about 8% of dietary fiber. Wherein the calorie content of tomato juice is low - an average of 19 kcal/100 ml. The article continues a series of publications on juices nutrient profiles.


Assuntos
Análise de Alimentos , Sucos de Frutas e Vegetais/análise , Valor Nutritivo , Solanum lycopersicum , Carotenoides/análise , Fibras na Dieta/análise , Metais/análise , Oligoelementos/análise , Vitamina A/análise , Vitamina E/análise
5.
Vopr Pitan ; 87(5): 85-94, 2018.
Artigo em Russo | MEDLINE | ID: mdl-30592894

RESUMO

Based on the published data on the content of nutritive (NS) and biologically active substances (BAS) and the results of studies of various samples of domestic industrial grapefruit juice, the article presents the nutrient profile of grapefruit juice containing data about more than 30 NS and BAS. Grapefruit juice is one of the relatively low-calorie fruit juices - 100 ml of grapefruit juice contains an average of 39 kcal. Like other citrus juices, it is rich in organic acids, the main of which is citric acid (0.8-2 g/100 ml). Potassium, magnesium, vitamin C, as well as flavonoids (mostly narigin) are the most significant for the estimation of nutritional and biological value of grapefruit juice of industrial production. A glass of grapefruit juice contains, on average, about 10% of the daily requirement in potassium, 6% - in magnesium and about 100% - in vitamin C. The amount of flavonoids in a glass of grapefruit juice provides up to 60% of the adequate daily intake. Conducted studies of fresh grapefruits purchased in the trade network show that the content of potassium, magnesium and vitamin C in grapefruit juice of industrial production is comparable to the content of these micronutrients in fresh fruits.


Assuntos
Citrus paradisi/química , Análise de Alimentos , Sucos de Frutas e Vegetais/análise , Valor Nutritivo , Flavonoides/análise , Magnésio/análise , Micronutrientes/análise , Potássio/análise
6.
Vopr Pitan ; 87(4): 78-86, 2018.
Artigo em Russo | MEDLINE | ID: mdl-30570961

RESUMO

Russia is one of the main producers of sour cherry, along with Turkey and Poland, and juice products from sour cherry are widely represented in the trade network. Sour cherry contains practically no sucrose, has a high content of organic acids, is rich in mineral and polyphenolic compounds, in particular, in anthocyanins, which give it a bright color. Sour cherry is close to many berries by its composition. At the same time, the literature data on the content of various natural substances in sour cherry juice are not numerous and need to be clarified, especially with reference to the industrially produced juice products. Organic acids of sour cherry juice are represented mainly by L-malic acid (1.2-2.7 g/100 ml). The most significant substances of sour cherry juice are polyphenolic compounds - flavonoids, mainly represented by anthocyanins (about 70% of them is cyanidin-3-O-glucosylrutinoside); phenolic acids - hydroxycinnamic acids, mainly represented by chlorogenic acids and 3-coumaroylquinic acid, as well as mineral substances - potassium, magnesium, copper and manganese. Sour cherry juice has a high acidity and is usually consumed in the form of nectars. Flavonoids content in a portion of sour cherry nectar is about 15% of adequate daily intake, anthocyanins - 20%, and the content of hydroxycinnamic acids - exceeds it. One portion of nectar contains on the average 10% of the daily requirement of the human body in copper and manganese, 6% in potassium and 3% in magnesium.


Assuntos
Antioxidantes/análise , Flavonoides/análise , Sucos de Frutas e Vegetais/análise , Metais/análise , Polifenóis/análise , Prunus avium
7.
Vopr Pitan ; 87(6): 95-105, 2018.
Artigo em Russo | MEDLINE | ID: mdl-30763495

RESUMO

The nutrient profile of grape juice is presented on the basis of reference books data analysis, scientific publications and research results. The profile contains more than 30 food and biologically active substances (BAS). Grape juice does not have high acidity, it contains on average 0.4 g of organic acids per 100 cm3. Tartaric acid and L-malic acid are major acids in grape juice. The presence of tartaric acid is a distinctive feature of grape juice, in other juices it presents extremely rare and only in traces. Potassium, magnesium, iron, manganese, as well as flavonoids and hydroxycinnamic acids are the most important for grape juice from the point of view of providing humans with micronutrients and minor BAS. Juices from red/purple grapes varieties contain anthocyanins (on average 3 mg/100 cm3), the color of grapes and grape juices are associated with them, about 50% of the anthocyanins are malvidin glycosides. Resveratrol (an average of 0.01 mg/ 100 cm3), a stilbenoid, is also found in grape juices, this substance is widely studied recently due to its high antioxidant activity. Caftaric acid prevails among hydroxycinnamic acids presented in grape juice (on average 5 mg/100 cm3). A portion of industrial grape juice contains, on average, 6-10% of human daily need for potassium, about 5-8% for magnesium, iron and manganese. The content of flavonoids per serving is about 25% of the adequate level of daily consumption, and the content of hydroxycinnamic acids exceeds it. Studies of fresh grapes purchased in commercial networks show that the content of magnesium, iron and manganese in grape juices of industrial production is comparable to the content of these micronutriens in fresh fruit.


Assuntos
Antocianinas/análise , Antioxidantes/análise , Sucos de Frutas e Vegetais/análise , Micronutrientes/análise , Fenóis/análise , Resveratrol/análise , Vitis/química , Humanos
8.
Vopr Pitan ; 86(4): 125-136, 2017.
Artigo em Russo | MEDLINE | ID: mdl-30695620

RESUMO

Fruits and vegetables are an important component of proper nutrition, but its consumption in Russia is below the recommended levels, and fruit and vegetable juices can partially fill the lack of fruits and vegetables in the diet. Russian Union of Juice Producers (RSPS) has been accumulating data on nutritive and biologically active substances of juices during five years to assess the contribution of juices to the diet. RSPS has organized research in accredited laboratories of more than 500 samples of reconstituted and direct juices available on the shelves of Russian stores since 2010 with the aim to specify and supplement the data listed in the various reference books. Analysis of literature data on the content of nutritive and biologically active substances is performed in the article together with the results of studies of various samples of apple juice of domestic industrial production. The nutrient profile of apple juice is given on this basis and contains 30 nutritive and biologically active substances. The most significant from the point of view of providing human body with micronutrients and minor biologically active substances for apple juice of industrial production are Potassium, Chromium and hydroxycinnamic (mostly chlorogenic) acids. A glass of apple juice (250 ml) contains, on average, about 8% of the daily requirement for potassium, 12.5% for chromium and about 150% of adequate daily intake of hydroxycinnamic acids. Additionally apple juices (except clarified ones) contain pectins - in a glass (250 ml) of juice on average there is 15% of daily requirement in pectins, and the total content of soluble and insoluble dietary fiber in apple juices with pulp on averages make 5% of daily human requirement in a dietary fiber.

9.
Vopr Pitan ; 86(6): 103-113, 2017.
Artigo em Russo | MEDLINE | ID: mdl-30592860

RESUMO

The article continues a series of publications on juices nutrient profiles. Based on the literature data, scientific articles on the content of nutritive and biologically active substances in orange juice and the results of studies of various samples of orange juice of domestic industrial production conducted by the Russian Union of Juice Producers (RSPS), the article presents the nutrient profile of orange juice which contains more than 30 nutritive and biologically active substances. Potassium, copper, folate, vitamin C, as well as flavonoids (mostly hesperidin) are the most significant for industrial orange juice from the point of view of providing human body with micronutrients and minor biologically active substances. A glass of orange juice (200-250 ml) contains, on average, about 14% of the daily requirement in potassium, 7% - in copper, 25% - in folates and about 100% - in vitamin C. The content of flavonoids in a glass of orange juice is about 60% of daily recommended intake of these substances. Orange juices contain dietary fibers - both soluble (pectins) and insoluble. The total content of soluble and insoluble dietary fiber in a glass of orange juice with pulp on averages is 5% of the daily requirement in dietary fiber.

10.
Biofizika ; 46(6): 1022-6, 2001.
Artigo em Russo | MEDLINE | ID: mdl-11771275

RESUMO

A comparative analysis of electrostatic potential distribution for "early" T4 phage promoters was undertaken. The data obtained indicate that there are some particular elements in the patterns of electrostatic potential distribution of promoter DNA specific for promoter groups differing by their functional response to ADP-ribosylation of the alpha-subunit as well as to rpoB403- or rpoB409 mutationals of the beta-subunit of RNA-polymerase.


Assuntos
Bacteriófago T4/química , DNA Viral/química , RNA Polimerases Dirigidas por DNA/química , Escherichia coli/química , Adenosina Difosfato Ribose/química , Bacteriófago T4/genética , RNA Polimerases Dirigidas por DNA/genética , Eletricidade , Mutação , Regiões Promotoras Genéticas
12.
Bioorg Khim ; 26(1): 68-77, 2000 Jan.
Artigo em Russo | MEDLINE | ID: mdl-10806554

RESUMO

Cerebroside sulfate (CGS) was found to be capable of inhibiting complement-dependent hemolysis. The activity dependence of CGS-containing liposomes on their composition was studied. Mixtures of CGS with phosphatidylethanolamine, phosphatidylserine, sphingomyelin from cattle brain, cerebroside from cattle spinal cord (CG), and egg yolk phosphatidylcholine (ePC) were investigated. In the case of binary CGS/ePC mixtures, the antihemolytic activity varied nonlinearly with an increase in the mass part of CGS: it sharply increased with an increase in the CGS part from 0.3 to 0.5 and decreased by 20-30% of the maximum value with an increase in the CGS part from 0.9 to 1. On the basis of these experiments, the optimum distance between the charged groups of CGS was estimated to be 0.92-1.6 nm. In the ternary compositions of 4:3:3 CGS/ePC/polar lipid, only CG increased the activity of liposomes as compared to that of liposomes from the 4:6 CGS/ePC. The preliminary incubation of CGS-containing liposomes with complement decreased hemolysis more effectively than incubation with other components of the hemolytic system. This suggests that the interaction of CGS-containing liposomes with the complement proteins is responsible for their antihemolytic activity.


Assuntos
Cerebrosídeos/farmacologia , Hemólise/efeitos dos fármacos , Animais , Bovinos , Ativação do Complemento , Portadores de Fármacos/farmacologia , Lipossomos/farmacologia
13.
J Biomol Struct Dyn ; 18(3): 325-34, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11149509

RESUMO

Comparative analysis of electrostatic potential distribution for "early" T4 phage promoters was undertaken, along with calculation of topography of electrostatic potential around the native and ADP-ribosylated C-terminal domain of RNA polymerase alpha-subunit. The data obtained indicate that there is specific difference in the patterns of electrostatic potential distribution in far upstream regions of T4 promoters differing by their response to ADP-ribosylation of RNA polymerase. A specific change in profiles of electrostatic potential distribution for the native and ADP-ribosylated forms of RNA polymerase alpha-subunit was observed suggesting that this factor may be responsible for modulating T4 promoter activities in response to the enzyme modification.


Assuntos
Bacteriófago T4/genética , DNA Viral/química , DNA Viral/genética , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/metabolismo , Regiões Promotoras Genéticas , Adenosina Difosfato Ribose/química , Adenosina Difosfato Ribose/metabolismo , Sequência de Bases , DNA Viral/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Eletricidade Estática
14.
J Biomol Struct Dyn ; 16(6): 1135-43, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10447198

RESUMO

Distribution of electrostatic potential of DNA fragments was evaluated. A method for calculation of electrostatic potential distribution based on Coulomb's law is proposed for long DNA fragments (approximately 1000 nucleotide pairs). For short DNA sequences, this technique provides a good correlation with the results obtained using Poisson-Boltzmann equation thus justifying its application in comparative studies for long DNA fragments. Calculation was performed for several DNA fragments from E. coli and bacteriophage T7 genomes containing promoter and nonpromoter regions. The results obtained indicate that coding regions are characterized by more homogeneous distribution of electrostatic potential whereas local inhomogeneity of DNA electrostatic profile is typical for promoter regions. The possible role of electrostatic interactions in RNA polymerase-promoter recognition is discussed.


Assuntos
Proteínas de Transporte de Ânions , DNA Bacteriano , DNA Viral , Proteínas de Escherichia coli , Regiões Promotoras Genéticas , Proteínas de Bactérias/genética , Bacteriófago T7/genética , Sequência de Bases , Escherichia coli/genética , Proteínas de Membrana/genética , Metiltransferases/genética , Dados de Sequência Molecular , Eletricidade Estática , Proteínas Virais/genética
15.
Appl Radiat Isot ; 51(3): 341-52, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10404614

RESUMO

Little information currently exists regarding the small-scale spatial variability of Chernobyl radiocaesium fallout and associated inventories. This contribution reports the results of a study of the variability of 137Cs inventories within the 2.18-km2 Lapki balka catchment located near Tula in central Russia. The local area was characterized by 137Cs inventories in excess of 200 kBq m-2 immediately after the Chernobyl accident and pre-existing bomb-derived inventories can be ignored in view of their very low magnitude. Field sampling and measurements included both collection of soil cores for subsequent laboratory analysis and in situ field measurements using a CORAD portable detector. The results obtained show evidence of a systematic south-north increase in the reference inventory across the basin, which must be taken into account when interpreting subsequent radiocaesium redistribution within the basin. Random spatial variability of 137Cs inventories of a similar magnitude to that reported for bomb-derived fallout was also documented. The extent of random spatial variability varied between different geomorphological units. Maximum variability, with coefficients of variation up to 20%, was associated with areas of sediment accumulation within the balka bottoms. Substantial variability (cv. typically ca. 15%) was found within flat cultivated areas and undisturbed areas both on the interfluves and on the balka sides, all of which could serve as reference sites. Minimum variability (cv. typically ca. 12%) was associated with the cultivated slopes with no evidence of sediment accumulation.


Assuntos
Agricultura , Radioisótopos de Césio/análise , Centrais Elétricas , Cinza Radioativa/análise , Liberação Nociva de Radioativos , Poluentes Radioativos do Solo/análise , Geografia , Monitoramento de Radiação/instrumentação , Monitoramento de Radiação/métodos , Análise de Regressão , Reprodutibilidade dos Testes , Federação Russa , Ucrânia
17.
J Biol Phys ; 24(2-4): 157-66, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23345676

RESUMO

Conformation behavior of phase T2 DNA in the process of its interaction with it E. coli RNA polymerase was studied using spin labeling technique. T2 DNA was modified by the spin-labeled imidazole at OH-groups of glucosylated cytidine residues. It was shown that the binding of RNA polymerase under the conditions favoring the formation of open promoter complexes induces specific conformational changes in the spin-labeled DNA. The observed conformational changes encompass not only the promoter regions of DNA which are involved in direct contacts with RNA polymerase molecules but extend over remote DNA sites (long-range effect). In relation to this effect, current theoretical models of DNA dynamics are discussed.

18.
Biofizika ; 43(3): 433-7, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9702334

RESUMO

Conformational behaviour of T2 DNA during its complex formation with E.coli RNA polymerase was studied by spin label technique. T2 DNA was selectively modified at its readily melting AT-rich sites by bromoacetooxypiperidine-1-oxyl-radical. Specific conformational changes are induced in DNA structure by RNA polymerase attachment. The changes are observed under the conditions when open transcriptionally competent complexes are formed. The readily melting sites of T2 DNA were shown to be involved in the formation of functionally active promoters.


Assuntos
DNA Viral/química , RNA Polimerases Dirigidas por DNA/química , Conformação de Ácido Nucleico , Conformação Proteica , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , DNA Viral/genética , DNA Viral/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Escherichia coli , Myoviridae , Regiões Promotoras Genéticas , Ligação Proteica , Transcrição Gênica
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