Studia Universitatis Moldaviae. Stiinte reale si ale naturii

10-14

Authors: Lidia COJOCARI, Aurelia CRIVOI

Stress resistance to teachers is determined by the specifics of professional activity, work stage and chronotype. To people with early morning chronotype, it was determined a higher stress resistance comparativ with the other cronotypes.

19-23

Authors: Ala CHERDIVARĂ

Seed storage 7S and 11S globulins of peanut and soybean as natural components of food can lead to the development of increased allergic sensitivity caused by the intensive formation of allergen-specific immunoglobulin E (IgE). The amino acid sequences of the seed storage globulins are conservative, therefore, in the sequences of many of them there are sites that are close similar of IgE epitopes of 7S and 11S globulins of peanuts and soybeans. In the present work, a quantitative assessment of the probability of the presence of IgE epitopes determining the established cross immunoreactivity of seed storage globulins of peanuts and soybeans, in the sequences of 7S and 11S seed storage globulins of other plants was carried out.

30-34

Authors: Yulia BEREZIUK

Was studied ability of a strain Streptomyces fradiae CNMN-Ac-11 allocated from soils of the central part of Moldova to accumulate biomass and to synthesize lipids depending on composition of medium. As additive to the main medium used the extract of amino acids and oligopeptides from Arthrospira platensis. An increasing yield of biomass of the studied strain (by 18.2%) when grown on medium in the presence of the extract at a concentration of 0.1%/V, and the amount of the sterol fraction in the biomass of the strain grown in the medium supplemented with the extract at all tested concentrations (by 7.0-58.51% in comparison with control).

41-46

Authors: Gheorghe FLORENŢĂ, Petru CUZA

It was determined the summary activity of oxidases, catalases and reducing substances of extracts from pubescent oak shoots taken in spring from trees growing in different stationary conditions in the southern part of the Republic of Moldova. In the extracts, the tendency to increase the overall capacity of oxygen use due to the reductive potential of the phenolic substances and the activity of the oxidases in trees growing southwards is clearly manifested, which corresponds to the gradient of increasing the spring temperature in the north-south direction. This trend also manifested itself in the catalase activity, but less pronounced. In apical buds, in spring, the changes in the components that determine the oxidoreductive potential are manifested earlier, compared to those in lateral buds. This acceleration may be a reason of the early removal of dormancy apical buds comparative with the lateral buds.

52-56

Authors: Andrei SIURIS

Solid wine yeast is formed by pressing the liquid yeast. It is found that they are concentrated fertilizers that can economically justify their transport over long distances, more than 10 km from the winery. Compared to conventional manure, dry yeast contains 2.7 times more nitrogen, 1.6 times more phosphorus, 2.4 times more potassium and 2.7 times more organic substances.

61-67

Authors: Ho Anh TUAN

Over time of analysis, we have identified 93 fish species belong to 81 genera, 43 families of 13 orders of valuable fishes, invasive fishes and dangerous fish for human in Gianh river basin in Quang Binh - North Central of Vietnam. Therein there were 5 species in this region being considered in the Red Book to be protected. Have 36 species is level Not Evaluated; 15 species is level Data Deficient; 37 species is level Least Concern; 3 species is level Near Threatened; 1 species is level Vulnerable; 1 species is level Endangered in this region being considered in The rare fish species in the IUCN Red List of Threatened Species. There are 84 species of fish having economic value, 4 invasive species and 26 dangerous fish for human.

78-85

Authors: Larisa MOCANU, Maria GONȚA, Gheorghe DUCA*

Lignosulfonic acid sodium salt is a dispersing agent has used in the process of dyeing fibers and fabrics widely. The initial concentration of the dispersing agent is 2000,0-5000,0 mg/L in the dyeing bath. Whereas lignosulfonic acid sodium salt has a complex structure and a high molecular weight, its removal was achieved by the Fenton reagent oxidation method. The optimum catalytic oxidation conditions have been established. It has been determined that the optimal value of pH is 2.5 as a result of the research. Also experimentally, it determined oxidizing and reducing ratio so as to oxidise/ mineralise 60,0 mg L of dispersing agent is necessary that the ratio of hydrogen peroxide and iron ions (II) is 1: 3,5. Under these conditions, the oxidation/ mineralization effect is on average 82.0%. For greater efficiency, oxidation with the Fenton reagent should be followed by the activated carbon adsorption process.

93-96

Authors: Mariana DÎRU, Ecaterina VÎLCU

A specific anionic sensor has been prepared, based on trinuclearchromium(III) pivalate as sensing material incorpo-rated into the plasticized PVC-membrane. The sensor exhibited Nernstian response (55,78 mV/decade) in the region between 10-1-10-4 mol/L with a detection limit of 2,0∙10-5 mol/L for fluoride. The working pH of the electrode was in the 5-6 range. The sensor has a response time 30-60 s and can be used for least 3 month. The potentiometric selectivity coefficients were determined by separate solution method. Application of these electrodes to the analysis of toothpaste containing fluoride has been realized and experimental results have been compared with the data on the prospectus.

107-115

Authors: Elena STRATULAT, Sergiu ȘOVA, Viorel PRISACARI, Ana DIZDARI, Ion CORJA, Aurel PUI, Oleg PALAMARCIUC

In this study we show the synthesis and crystallographic investigation of Cu(II) coordination compounds with 8-formyl¬quinoline thiosemicarbazone. In dilute solutions the copper ions react with organic reagents at room temperature to form 1:1 = metal:ligand yellow coloured complexes. Complex of copper(II) with 8-formylquinoline 4-phenyl-thiosemi¬car¬bazone in aqueous ethanol solution is characterized by a maximum absorption located at λ=390 nm. The calibration curve has a linear character in the range of copper concentrations 2.5∙10-6 ÷ 4∙10-5 M. The 8-formylquinoline 4-phenyl¬thiosemicarbazonev is proposed for the spectrophotometric determination of copper(II) ions in solution. The method has been successfully applied for the determination of copper when the yield of coordination reactions with organic ligands is small. Compound [CuLAc] exhibiting antibacterial activity against Staphylococcus aureus (strain 209-P), Entrecoccus faecalis and Proteus vulgaris bacteria.

120-123

Authors: Нелли ГОРЯЧЕВА, Виорика ГЛАДКИЙ, Елена БУНДУКИ

The work contains the results of statistical processing of indicators of the oxidizability of waters of the Dniester and tributaries. The revealed correlation dependence of dichromate oxidizability on the permanganate one is presented, the tightness of the bond, the form of the coupling equations, the level reliability of coefficient of determination.

8-13

Authors: Lidia COJOCARI, Aurelia CRIVOI

The process of adapting to a program activity is a complex reaction in the evaluation of which play a particular role regulating relations between systems and functional activity. The cardiovascular system has an enhanced reactivity among the first to include the mechanisms for maintaining biological balance of the body. Working in night hours distort physio¬logically functional stereotype, leading to temporary discrepancy between his behavior and providing vegetative body.

19-21

Authors: Eugeniu DUDNIC, Ecaterina ERHAN, Natalia DUDNIC

The people involved in the field of sport need to be informed permanently about the factors that influence the food ration, food intake, use of substances and nutritional supplements. In the experimental study conducted to investigated the effect of high doses of soybean protein on some hematological indices in the animal body.

29-36

Authors: Светлана ЖУБЫРКЭ, Светлана ГАРАЕВА, Анна ЛЕОРДА, Влада ФУРДУЙ, Галина ПОСТОЛАТИ, Галина РЕДКОЗУБОВА, Нина КОВАРСКАЯ

The article discusses the features of amino acid metabolism and nitrogen metabolism products among minors in the third trimester of pregnancy. It was found that the exchange of aromatic amino acids, particularly tryptophan, with a high probability of developing depression reflects minor pregnant, and immune status at less and less stable than in adults and pregnant women may contribute to clinical manifestation of a large number of infectious symptoms. Also there is a sharing of sulphur-containing amino acid imbalance. The coefficient is indispensable / replaceable free amino acids, indexes C, tyrosine/phenylalanine, so as homocysteine, and amino acid dicarboxylic concentration be recommended as indicators for screening pregnant women at risk for the purpose of prenatal diagnosis and implementation in practice of genetic counseling.

41-45

Authors: Ala CHERDIVARĂ, Angela RUDACOVA, Serghei RUDACOV, Andrei ŞUTOV

The final product of trypsin limited proteolysis of a subunit of storage 11S globulin from peanut seeds Ara h3 (pdb|3c3v) consists of the intact -chain and -chain fragments K and N. The fragment K disulfide bonded with the -chain corresponds to the N-terminal half of the -barrel (Ile1-Arg109), and the fragment N corresponds to the adjacent C-terminal half (Lys110-Arg213). Identification of the respective -chain cleavage points is based on the results of electrophoresis, the molecular mass of the residual protein determined using two independent methods, and on the analysis of the level of accessibility of amino acid residues in a model structure of Ara h3 hexamer molecule. The destruction of the -chain C-terminal region occurs in the course of formation of the fragments K and N. This region contains three of the four antigen determinants (IgE epitopes) identified in Ara h3. Thus, it seems likely that trypsin limited proteolysis can essentially decrease the allergenicity level of the peanut 11S globulin.

51-56

Authors: Maricica COLȚUN, Elvira GILLE, Radu NECULA, Valentin GRIGORAȘ

The paper presents the results of a vast study on the biology, chemical composition and qualitative phytochemistry of the essential oil of the species Perovskia atriplicifolia, which behaves like a perennial, herbaceous plant in the Lamiaceae family. In the Republic of Moldova, it has not been investigated as an aromatic and medicinal plant. It has a high ecological plasticity and no special requirements to climatic factors. It has febrifuge properties and is used in medicine to reduce fever. Besides, this plant is used for culinary, ornamental purposes and for air purification.

61-64

Authors: Sergiu DOBROJAN, Irina STRATULAT, Galina DOBROJAN

The present research is focused on the analysis of the blue-green alga Calothrix sp. growth process cultivated on BG-11 liquid nutrient medium. Cultivation of Calothrix sp. on BG-11 allows to obtain 2,38 ± 0,11 g/l of algal biomass during 12 days. The highest values of the daily growth of the biomass, the rate of reproduction, reproduction coefficient and the growth rate of the Calothrix sp. algal population, is found in the range from 1 to the 12th day of cultivation, but on the 15th day of cultivation the results of these indicators are significantly reduced. From the 3rd day to the 12th day of cultivation linear growth phase are carried out, and to 15th day is observed the decline growth stage.

69-73

Authors: Alexandru MÎRZA, Nina CIORCHINĂ, Ion COMANICI

Here, we established the protocol for plant regeneration of Rubus loganobaccus L.H. Bailey via in vitro micro pro-pagation. Apical meristem was used as the explants cultured on Murashige and Skoog (1962) medium (MS) supple-mented with different concentrations of plant growth regulators, 6-Benzylaminopurine (BAP). For the cultivars Logan, Chehalem, Olalie and Kotata good results were obtained for 0.5 mg/l BAP concentration, whereas for the cultivars Santiam and Lincoln Logan results were obtained for 0.4 mg/l BAP concentration. The micro-shoots produced normal roots within two weeks of culture on the 50% MS medium with no supplement of plant growth regulators. Plantlets were transferred to celled trays where they grew well.

83-88

Authors: Ana MUTU

The paper reveals a comparative synthesis of the researches carried out in the field of medicinal and aromatic plants. It is analysed the importance of correlating the phenotypic, biochemical and molecular studies for new breeding programs of various forms of medicinal and aromatic plants with economic valuable characters. On the example of the Origanum genus, it concludes about the effectiveness of genetic fingerprinting techniques to identify new subspecies and chemotypes.

96-107

Authors: Tatiana ERHAN

This paper presents a review of N(4)-arilthiosemicarbazide derivatives. The synthesis methods of N(4)-arylthio-semicarbazides and their derivatives are described. There are also represented the possible ways of modification of their biological properties. The antiproliferative activity towards HeLa, MCD-7, SW620, MiaPaCa-2, and Hep-2 cancer cells and antimicrobial activity of these substances are revealed. These biological properties make it possible to use them as the basis for the obtaining of new performant molecular inhibitors that can be used in anticancer therapy. Some ways of the development of organic synthesis for the obtaining of new derivatives of N(4)-arilthiosemicarbazides were outlined.

118-123

Authors: Ketevan KUPATADZE

Popularization of Ecological Chemistry is the aim of scientific-popular articles, which are published in the online journal for teachers. With the articles of this type Ecological Chemistry is linked with literature and history. Due to this linkage articles, this module turns into an easily comprehensible one and it becomes fun. In all articles there is also included very useful and interesting information pertaining to Ecological Chemistry. It must be underlined the titles of such articles, because they should not only show the common meaning of article, but they should also attract readers. The utmost interest is generated by the historical papers, where chemical issues are connected with history. The period of alchemy is more popular and that’s why the alchemical stories are described in the articles. The outcome of the pedagogical experiment has made it clear, that such a method of teaching of Ecological Chemistry with scientific popular articles affects positively on school students motivation and changes their attitude towards the environmental pollution.