Studia Universitatis Moldaviae. Stiinte reale si ale naturii

3-16

Authors: Ana BÎRSAN, Aurelia CRIVOI, Iurie BACALOV, Maria FRUNZĂ, Veaceslav REVA, Silvia STRATULAT, Drăgălina BÎRSAN

In view of analysing this topic, specialised literature sources available in the MSU library and in the NCBI, MedPUB, Google scholar databases were selected. The analysis of these sources was carried out starting from the main medicinal plants used in the treatment of respiratory diseases: Althaea officinalis L., Hedera helix L., Hippophae rhamnoides L., Inula helenium L., Malva sylvestris L., Marrubium vulgare L., Origanum vulgare L., Plantago major L., Primula veris L., Sambucus nigra L., Silybum marianum L., Taraxacum officinale L., Thymus vulgaris L., and Tussilago farfara L. The results of the study allowed the identification of medicinal plants with anti-inflammatory activity, which could serve as potential sources of prophylaxis/treatment in the case of COVID-19. For all selected plants, scientific evidence was presented with regard to their anti-inflammatory activity, which indicates on the possibility of using these plants in mitigating the symptoms in COVID-19.

26-33

Authors: Ион МЕРЕУЦЭ, Федор СТРУТИНСКИЙ, Светлана ГАРАЕВА, Лилия ПОЛЯКОВА, Владимир КАРАУШ, Галина ПОСТОЛАТИ, Марьяна ЧОКИНЭ, Виктория БОГДАН

The COVID-19 pandemic poses a major threat to human health and life. Elderly people with low immunity are at a particular risk. To discover the mechanisms of coronavirus influence on the human body, an important role is assigned to the study of the influence of coronavirus on amino acid metabolism. The article presents results on the age-related peculiarities of amino acid metabolism in patients infected with the SARS-CoV-2 virus.

39-43

Authors: Elisaveta ONICA, Ion ROȘCA, Alina CUTCOVSCHI-MUȘTUC

The bioecological peculiarities of growth, development and cultivation of Prinsepia uniflora Batalin plants are described in this article. This shrub can be propagated by generative and vegetative methods, namely, by lignified cuttings and by layering. Early autumn fresh seeds sowing at a depth of 2-3 cm was the optimal and most cost-effective method of propagation. The germination capacity of the seeds sown in autumn varied in the research years, from 60 to 65% and of those incorporated in spring after stratification was only 40-45%, depending on the climatic conditions, following the cultivation techniques throughout the growing season. The plants are valued for their decorative qualities, in early spring – for the abundant, white flowers, and in early autumn – for the hanging branches full of black-purple fruits. It is recommended for use in landscaping in rural and urban areas of the country.

49-53

Authors: Vasile TODIRAȘ, Maria MELNIC, Svetlana PRISACARI, Angela LUNGU, Ștefan RUSU, Dumitru ERHAN

The stimulatory effect of the nodule bacterium Rhizobium on the growth, development and productivity processes in tomato and cucumber plants was studied. It has been established that treating seeds with bacterial metabolites in optimal concentrations (1:300; 1:500) stimulates the growth and accumulation of dry mass of plants. The effect of bacteria on phytoparasitic nematodes – Ditylenchus destructor – was also investigated.

60-65

Authors: Iurie BACALOV, Aurelia CRIVOI, Elena CHIRIŢA, Ana BÎRSAN, Adriana DRUŢA, Dragoș GHERAS

The PHASC-5 biopreparation leads to the improvement of the functional state in the pathology of the endocrine pancreas by removing or reducing the complications in the case of people suffering from diabetes. Thus, blood sugar is reduced and the hormonal balance is restored due to the bioactive principles it contains. The administration of PHASC-5 biopreparation in experimental diabetes allows to eliminate or even exclude the occurrence of acute and chronic complications in this pathology.

75-81

Authors: Tamara SÎRBU, Ion TIMUȘ, Olga ȚURCAN, Cristina MOLDOVAN, Viorina GORINCIOI

The last important stage of lyophilisation is rehydration, which has a major influence on the viability of microorganisms. Various nutrient media, skim milk, distilled water, etc. are used as rehydration media for lyophilised micromycetes. In this study, distilled water and nanoparticle (NP) solutions Fe2O3 and Fe2ZnO4 in a concentration of (mg/l): 0.05; 0.1; 1.0 were used for the rehydration of lyophilised strains of micromycetes. The obtained results showed that the solutions of NP Fe2O3, and NP Fe2ZnO4, in a concentration of 0.1 mg/and 0.05 mg/l, had a different influence on the viability of micromycetes. In some strains of the genus Penicillium there was a stimulation of viability of 7-8%, and in others a decrease of 6-9%, compared to the control variant. The viability of strains of the genus Aspergillus and Trichoderma decreased by 5-10% when using NP at a concentration of 0.05 mg/l, and at a concentration of 0.1 mg/l varied within ± 2-3%, compared to the control variant.

93-102

Authors: Ilie BOIAN, Rodion DOMENCO

With the help of modern statistical programs, the present study carried out the generalised climatic and agro¬climatic characterisation of the spring season on the territory of the Republic of Moldova based on factual data for the last 50 years, with the elaboration of maps of the distribution of multiannual average air temperature of precipitation in the spring season. Also, the springs of the last two decades (2001-2020) were analysed from a climatic and agroclimatic point of view, two anomalous springs being selected according to the thermo-pluviometric regime (2007 and 2012). For these springs, maps were developed regarding the distribution of the average air temperature and the amount of preci¬pi-tation, as well as the distribution of the values of the respective deviations from the norm for each evaluated spring season, and the analysis of these maps made possible the climatic and agroclimatic evaluation of the selected anomalous springs. The very high thermal regime and the significant deficit of precipitation, signalled in particular during the month of May in both anomalous springs (2007 and 2012), contributed to the drying of the upper layer of the soil, which created unfavou¬ra¬ble conditions for the growth and development of autumn crops and spring cereals and for the emergence of hoeing crops.

109-114

Authors: Tudor LUPAŞCU, Mihai CIOBANU, Oleg PETUHOV

Inflection points of strontium ion adsorption isotherms on CAN-7 and oxidized CAN-8 activated carbons were studied. The causes of inflection points on strontium ion adsorption isotherms on CAN-7 and oxidized CAN-8 activated carbons, obtained in the laboratory from walnut shells were identified. Studies have shown that the bonds between Sr(OH)+ and strong and weak carboxylic groups in the micropores and supermicropores of CAN-7 activated carbon are stronger than those in mesopores and macropores. The differential heating curve (DTA) of strontium ions adsorbed on CAN-7 has two thermal effects: one endothermic and the other exothermic.

119-125

Authors: Viorica GLADCHI

The article is an analysis of statistical data on emissions of pollutants into the air from various sources in the Republic of Moldova during 2015-2019. The mobile and stationary sources of pollutant emissions are highlighted, the dynamics and their polluting effect are analysed, as well as the influence of pollutant emissions on the environment and the health of the population.

132-140

Authors: Olga GARBUZ, Ion TODERAS, Nadejda RAILEAN, Victor TAPCOV, Aurelian GULEA

Based on the known methods and their modifications, 3 compounds were synthesized: 2-formylpyridine N(4)-phenyl¬thiosemicarbazone, complex copper(II) [Cu(L)Cl] with 2-formylpyridine N(4)-phenylthiosemicarbazone ligand, copper(II) mixed-ligand complex chloro(N-phenyl-N'-[(pyridin-2-yl)methylidene]carbamohydrazonothioato)(4-aminobenzene-1-sulfonamide)copper [Cu(Str)(L)Cl]. The antiproliferative properties of these compounds towards cancer cell lines MeW-164 and HeLa have been investigated. The tested compounds demonstrated antiproliferative and selective activity towards cancer cells. The tested compounds inhibit the activity of LOX. Direct toxic evaluation of compounds was performed by Daphnia magna bioassay. It was found that the tested compounds have a lower toxicity than DOXO. Theoretical pharma¬cokinetics (Lipinski's rule, PSA) of CMT-22, CMT-67 and CMT-68 supports further in vivo studies.

149-157

Authors: Елена ТУТОВАН, Татьяна ИСАК-ГУЦУЛ

The adsorption of methylene blue dye (MB) on native natural tripol was studied. It has been established that MB adsorption on tripol increases with the growth of pH. The form of the MB adsorption isotherm on tripol is of the Langmuir type. There were determined the constants from the Langmuir isotherm (qmax = 107.527 mg/g, K = 0.046 L/mg) and Freundlich isotherm ( = 10.021 mg/g, 1/n = 0.517) and it was established that the adsorption process is more accurately described by Langmuir model. It was detected that the equilibrium is established practically after 8 hours of the MB solution contacting with the tripod. In general, the kinetics of the MB adsorption process on tripol is described by the pseudo-two order kinetic model (к2 = 2.13  10-2 gh-1mg-1).

3-10

Authors: Iurie BACALOV, Adriana DRUŢA, Aurelia CRIVOI, Elena CHIRIŢA, Luminiţa SUVEICĂ, Iulian PARA, Ana ILIEŞ

The researched biopreparation demonstrated a homeostatic effect on the functional state of the body in the pathology of the endocrine pancreas by removing or reducing complications in people suffering from diabetes. The advantage of using the preparation given in experimental diabetes is its accessibility, mild action and lack of side effects. Its administration reduced blood glucose and stimulated insulin, leukocytes, lymphocytes, monocytes, granulocytes in acute and chronic complications of experimental diabetes.

30-36

Authors: Maria FRUNZĂ, Ana BÎRSAN

In the present work the influence of nanocomposite structures based on vanadium oxides on the mitotic divisions in radicular meristems at Allium cepa L. was studied. The cytological analysis revealed the presence of abnormal mitoses and chromosomal aberrations in the experimental variants with exposure to nanocomposites, based on division spindles. This indicates the cytotoxic and genotoxic character of the studied materials.

42-49

Authors: Vladimir ȘEPTIȚCHI, Ana LEORDA, Viorica RAISCHI

Oxidative stress is a major causal factor in sperm dysfunction. Dietary supplements, which contain nutrients to improve sperm quality have a significant effect on male reproductive function. With their use, there is a decrease in oxidative damage to DNA, a substantial improvement in sperm quality parameters and overall reproductive function. The use of nutritional supplements, along with changes in diet, lifestyle and environmental conditions will improve not only the parameters, which determine the reproductive potential, but also the birth rate.

58-67

Authors: Ion BURCOVSCHI, Ruslan TABACARI, Maria DUCA

Sunflower is one of the main oil crops, which is affected by a large number of pathogens that cause yield and crop quality losses. This paper presents a quantification of national and international publications on the main diseases of sunflower, in an attempt to identify the researchers’ directions of interest in this field. A bibliographic review is made for five of the most common pathogens of sunflower: Plasmopara halstedii (P. helianthi), Orobanche Cumana, Sclerotinia sclerotiorum, Duaporthe helianthi, and Phoma macdonaldii and the data on their spread in different areas of the Republic of Moldova during the last six years is presented.

78-88

Authors: Rodion DOMENCO, Ilie BOIAN

In the present study, based on the processing and statistical analysis of factual data for the last 50 years (using modern statistical programmes), the generalised climatic and agroclimatic characterisation of the winter season on the territory of the Republic of Moldova was carried out with the development of maps on the multiannual air average temperature and multiannual average amount of precipitation distribution in the winter season. Also, the winters in the Republic of Moldova for the last two decades (2001-2020) were evaluated from a climatic and agroclimatic point of view, making possible the selection of three winters characterised by the highest degree of deviation from the climatic norm of the average air temperature and the amount of precipitation (2006-2007; 2011-2012; 2019-2020), with the elaboration of maps for each evaluated winter season. The 2006-2007 winter season was abnormally hot. The average air temperature in the territory of the republic was +0.9…+2.8ºС, being higher than the norm by 4.1-4.6ºС. Positive average monthly temperatures stayed through¬out the three winter months. The amount of precipitation during the winter in the country was basically 70-90 mm or 70-90% of the norm. The 2011-2012 winter season was characterised by a varied thermal regime, being basically colder than usually and with precipitation. Some shorter periods of the winter season were abnormally cold. The average air temperature during the winter on the territory of the republic was -2…-4ºС, being basically lower than the normal values by 0.5-1.3ºС. The number of days with air temperature ≤ -15ºС, ≤ -20ºС and ≤ -25ºС significantly exceeded the climate norm, being practically analogous according to this criterion with 2009-2010 winter. The amount of precipitation during the season was 75-145 mm on 90% of the country's territory, or 80-150% of the norm. The 2019-2020 winter season was abnormally hot and basically with a deficit of precipitation. The average air temperature in the territory of the republic was +1.6…+3.3ºС, being 4.3-5.4ºС higher than the norm, a fact reported for the first time in the entire period of instru¬men¬tal observations. The amount of precipitation which fell was low and with an uneven spatial-temporal distribution (basically – 40-65 mm or 40-70% of the norm). The meteorological conditions for the wintering of autumn cereals, fruit trees and vines in the 2006-2007 and 2019-2020 winter seasons were basically satisfactory. A completely different situation was created during the winter of 2011-2012, when on a large part of the republic there were unfavourable thermal conditions for the winter of autumn cereals, fruit trees and vines, causing significant losses to the agricultural sector.

97-103

Authors: Angela RUDACOVA, Serghei RUDACOV, Ala CHERDIVARĂ, Liliana MĂRÎI, Larisa ANDRONIC

To study of the peroxidase activity under the influence of tobacco mosaic and tomato aspermy viruses, samples of 20 tomato genotypes were selected by the team staff of the Institute of Genetics, Physiology and Plant Protection and evaluat¬ed. Under the influence of the tobacco mosaic virus, an increase in the total activity of peroxidases was detected in 9 geno¬¬types of tomatoes. Among them, the greatest effect was established in samples no.20 (+143%) and no.21 (+117%). The tomato aspermy virus was reacted to by an increase in the activity of 12 of the studied genotypes. The most significant increase in activity was also exposed by the sample no.20 (+444%). The genotype no.4 and no.19 showed a significant increase in activity – by 160% and by 181%. When studying the electrophoretic spectra of peroxidase enzymes in the studied tomato genotypes, 8 isoenzymes with molecular weights from 45.5 kD to 23.1 kD were found, peroxidases with a large molecular weight were conventionally designated as zones A1, A2, A3, A4, zones with a lower molecular weight were noted B1, B2, B3 and B4. The largest number of peroxidase enzymes was found in sample no.20, in which all 8 isoforms of peroxidases were found. In one of the samples, namely, in sample no.19, 5 initial zones of peroxidases (A1-A4 and B2) were detected, but under the action of the tomato aspermy virus, 2 new zones appeared in its peroxidase spectrum – B1 and B3, in addition, the intensity of zones A2-A4 and B1-B3 increased by 2.8 times. Under the influence of the tobacco mosaic virus the intensity of zones A1, A2 and A4 increased by 1.75 times. In four samples (no.14, no.1, no.2, no.3) there were 7 zones of isoenzymes A1-A3 and B1-B4. Among these samples, the most interesting was sample no. 14 (+160%). Under the influence of the tomato aspermy virus, the intensity of all its zones increased significantly, but the intensity of zone A2 (4.9 times) and zone A1 (2 times) increased the most.

116-120

Authors: Elena PELEAH, Victor MELNIC, Nicolae CIOBANU, Marina BEJINARI

Mentha spicata L. collected from eight different regions of Moldova were analysed to determine essential oil constituents. Ecotypes of M. spicata L. did show quantitative and qualitative differences. Three mint chemotypes were found, depending on component composition – synthesising carvon, linalool or menthol and keto-oxides as the main components. The studied chemotypes showed significant bactericidal and fungicidal activity.

127-132

Authors: Serghei BALACCI

For the first time, the field of veterinary pharmaceuticals and the welfare conditions of the animal sector in the Republic of Moldova were evaluated. The particularities, structure and trends of the authorised units for the manufacture, ownership, distribution and dispense of veterinary medicines, feed additives and mineral premixes were studied. It was found that the amount of veterinary medicines, feed additives and mineral premixes produced in the Republic of Moldova does not fully cover their need (7.9% in 2020). Thus, the largest share of veterinary pharmaceuticals is covered by imports.

137-145

Authors: Maria SANDU, Anatol TĂRÎŢĂ, Viorica GLADCHI, Galina DRAGALINA

The presence in natural waters of non-ionized ammonia, which is a mineral form of nitrogen, leads to the essential increase of the toxicity of the aquatic environment and represents a real danger for aquatic biodiversity. Its main sources are the economic activities in the republic (yeast, beer, soft drinks, milk, meat and fish processing, leather, animal complexes, etc.) and wastewaters, which discharge into aquatic objects without sufficient purification or even untreated. The Prut River, being also a transboundary water artery, represents in this case a collector in which the polluting substances are stored, which contributes to the diminution of the water quality. The present study includes the evaluation of the content of non-ionized ammonia (NH3) in the waters of the Prut River and its left tributaries, based on existing information in scientific publications, on the total concentration of ammonium compounds (NH3 + NH4+) based on pH.

172-180

Authors: Tatiana ISAC-GUŢUL, Elena TUTOVAN

The present work studies the optimal conditions of oxidation of some sulfonamides (SA) antibiotics representatives – phtalazole (FL) and acetazolamide (AC) with MnO4-ions in aqueous solutions in basic medium in KMnO4-SA-NaOH systems: [KMnO4] = (0.5-2.0)10-3 M; [NaOH] = 0.05 M, [NaClO4] = 0.005-0.05 M, [SA] = (0.1-1.0)10-3 M. For the study of kinetic regularities, the spectrophotometric method was used, the absorbance of reaction mixture at different time points was measured, at  = 525 nm, corresponding to maximum of permanganate ions absorption. By using the spectrophotometric method we found that MnO42- ions are formed in basic medium. The electronic spectra show the disappearance of the band for KMnO4 absorption during the reaction at 525 nm and the appearance of the new maximum at 625 nm, characteristic for the manganate ion. The activation energy in the KMnO4-AC-NaOH system based on the Arrhenius equation was determined, the value being 62.2 kJ/mol.

187-194

Authors: Nelea POPA

The paper relates on the synthesis and investigation of Ln(III)-Bi(III) heterometallic complexes based on diethylene¬triaminepentaacetate ions (dtpa5-) with the general formula LnBi(dtpa)·10H2O (Ln(III) = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb). The complexes have been used as precursors to generate BiLnO3 mixed-oxides upon thermolysis. The results of IR spectroscopy revealed the presence of one single series of analogous complexes. Thermogravimetric analysis demonstrated that at 0.5oC·min-1 heating rate the thermal decomposition process of the precursors ends with the formation of inorganic residues at 530-580oC, which is 100-160oC lower than the values registered at 10oC·min-1 heating rate. Powder X-ray diffraction patterns of residues obtained upon thermal decomposition of the precursors de¬monstrated that heating rate affects the composition of the final residue: at 0.5oC·min-1 heating rate, pure anticipated BiLnO3 mixed-oxides are obtained, regardless the nature of the lanthanide, while at 10oC·min-1 the desired oxides are contaminated with carbonate species.