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1.
The purpose of this work is to perform a detailed study of carbohydrate specificity of the new extracellular bacilli lectins which is considered to determine mechanisms of the lectins action. Sources of lectins were bacterial strains from Ukrainian collection of microorganisms. The optimized protocol of bacilli lectins isolation and purification included precipitation with ammonium sulfate with subsequent gel filtration chromatography on Sepharose CL-6B. Hemagglutinating activity of bacilli lectins and their fine carbohydrate specificity to sialic acids and their derivatives as well as sialic asid-containing and asialic glycoconjugates were studied. The ability of extracellular bacilli lectins to discriminate a- and 13-conformation of carbohydrate molecule and the type of connection between the monomers was determined. Studied lectins showed the most affinity to glycoconjugates containing both types of sialic acids (N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (NeuGc)) and it is supposed to be a basis of their diagnostic and analytical potential.  相似文献   
2.
Recently natural antioxidants have gained increased interest because natural food ingredients are safer than synthetic ones. Antioxidant activities and protective effects of sesame cake extract (SCE) in stabilizing sunflower oil (SFO) and soybean oil (SBO) were tested. Since different antioxidant compounds have different mechanisms of action, 2,2-azinobis (3-ethylbenzthiazoline sulfonate) (ABTS) radical scavenging activity, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity, and β-carotene/linoleic acid test system were used to assess the antioxidant efficacy of SCE. Total phenolic, flavonoid and flavonol contents in SCE were 1.94 (mg gallic acid equivalent (GAE) g−1 dry weight (DW)), 0.88 (mg quercetain equivalent (QE) g−1 DW), and 0.40 (mg QE g−1 DW), respectively. Protective effects of SCE in stabilizing SFO and SBO were tested, compared to synthetic antioxidants, by measuring their peroxide values (PV), conjugated dienes (CD), conjugated trienes (CT) and p-anisidine value during accelerated storage. Results indicated that SCE exhibited stronger antioxidant activity in SFO and SBO than butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA), while its antioxidant activity was less than that of tert-butyl hydroquinone (TBHQ).  相似文献   
3.
Development of artificial crayfish egg incubation is a milestone in intensive culture of crayfish as commercially important freshwater animals. This study evaluated experimental treatments combining continuous UV lighting, a non‐chemical antifungal treatment, with an initial formaldehyde bath for noble crayfish (Astacus astacus) eggs incubated in semi‐recirculating systems, which requires less than 1 per cent the amount of water necessary for conventional flow‐through systems. The one‐time administration of a pre‐incubation bath to reduce formaldehyde exposure was ineffective. Ultraviolet irradiation of recirculating water provided poor results (13.5% and 35.2% final survival rates to stage 2 juveniles) and led to deteriorating water quality. An inability of hatchlings to successfully moult and the occurrence of limb deformities was observed in UV‐treated groups, and juvenile mortality was found across all experimental treatments.  相似文献   
4.
This study is focused on the selection analysis of high rutin contents in various buckwheat species and cultivars, such as Fagopyrum esculentum Moench. (Cultivars Lileya, Bilshovik, Rubra), F. tataricum G. (ssp. rotundatum (Bab) Krot. and ssp. tuberculatum Krot.), F. cymosum Meissn, and Fagopyrum giganteum Krot. Rutin contents in vegetative organs of plants showed good correlation with anthocyanins contents in vegetative organs of Rubra cultivar. The presence of anthocyanin’s contents in the vegetative organs of buckwheat can be a reliable genetic marker for screening plants with high content of rutin. In the third generation of selection process with the proposed selection method by us, a genetic line of Rubra cultivar with high rutin content in the vegetative mass has been obtained. The proposed method of selection based on the color visual assessment of plant parts of buckwheat which is correlated with anthocyanin contents. The color visual assessment of vegetative organs of buckwheat plants can be marker for selection buckwheat cultivars with high anthocyanin’s and rutin contents.  相似文献   
5.
Soil salinity is one of the major environmental constraints to crop productivity worldwide. Therefore, the development of cost-effective and environment-friendly techniques allowing increased crop productivity and soil fertility under saline conditions is rather urgent today. The objective of this investigation was to study the effects of mixtures containing natural silicates (analcite, bergmeal, and potassium silicate) and organic fertilizers (sapropel, peat) in corn (Zea mays L.). We specifically evaluated tolerance of corn to salinity stress and certain characteristics of saline soil (viz., redox potential, conductivity, and phytotoxicity) using a factorial pot experiment, modeling NaCl salinity levels of 0, 50, 100, 150, and 200 mM under greenhouse conditions. Growth, water balance, photosynthesis, catalase activity, and accumulation of nonenzymatic antioxidants (flavonoids and anthocyanins) were measured and evaluated. Salinity stress reduced shoot and root biomass by 8–49%, photosynthetic pigment content in leaves by 15–30%, deteriorated water balance, and activated nonspecific adaptive reactions (i.e., accumulation of enzymatic and nonenzymatic antioxidants) in the corn seedlings. All the tested silicon-containing mixtures stimulated corn seedling resistance to salt stress and reduced soil phytotoxicity. This was reflected in the stimulation of growth of the corn seedlings (accumulation of shoot biomass, and formation and growth of lateral roots). The content of photosynthetic pigments, flavonoids, anthocyanins, catalase activity increased 1.3–2 times compared with plants that received NaCl only. The difference between treatments and control was most pronounced at moderate levels of salinity (100–150 mM). The mixture containing silicon minerals and sapropel (9:1 proportion) showed the highest protective effect against salinity stress.  相似文献   
6.
This article investigates the role of universities in the economic development of American metropolitan regions during the Great Recession (2007–2009) and the growth period prior to it (2001–2007). It develops a supply‐side conceptual framework on the role of universities in technology‐led regional economic development. Specifically, this framework highlights three “university products” that can be explicitly defined and measured: educational services, business services, and new knowledge or technology. The empirical test of this conceptual framework finds that the presence of universities is positively associated with regional economic performance during the Great Recession, mainly via the educational services product. Findings indicate that regions with a higher level of university science, technology, engineering, and mathematics graduates are more resilient to the economic recession.  相似文献   
7.
In declining broadleaf forests in western Ukraine, several Phytophthora species including P. plurivora, P. bilorbang, P. polonica, P. gonapodyides and P. cactorum were recovered using soil baiting assays and identified using morphological and molecular methods. Pathogenicity tests of selected isolates were performed on black alder (Alnus glutinosa (L.) Gaerth.) and silver birch (Betula pendula Roth.) to assess susceptibility of these two tree species to the newly detected Phytophthora species. Phytophthora plurivora, P. bilorbang and P. polonica showed higher pathogenicity in both alder and birch compared to the other tested Phytophthora species.  相似文献   
8.
Elicitation studies with salicylic acid (SA) and methyl jasmonate (MJ) inducing a targeted rhizosecretion of high levels of anticarcinogenic glucosinolates in Brassica rapa ssp. rapa plants were conducted. Elicitor applications not only led to an accumulation of individual indole glucosinolates and the aromatic 2-phenylethyl glucosinolate in the turnip organs but also in turnip root exudates. This indicates an extended systemic response, which comprises the phyllosphere with all aboveground plant organs and the rhizosphere including the belowground root system and also root exudates. Both elicitor applications induced a doubling in 2-phenylethyl glucosinolate in root exudates, whereas application of MJ enhanced rhizosecreted indole glucosinolates up to 4-fold. In addition, the time course study revealed that maximal elicitation was observed on the 10th day of SA and MJ treatment. This study may provide an essential contribution using these glucosinolates as bioactive additives in functional foods and nutraceuticals.  相似文献   
9.
One of the most important tasks in precision farming is the site-specific application of fertilisers and pesticides in heterogeneous large-area fields. For such site-specific crop management, effective remote sensing methods for the detection of crop diseases and nutrient deficiencies are required. The aim of the present work was to compare laser-induced fluorescence (LIF) parameters from nitrogen-deficient and pathogen (rust and mildew)-infected winter wheat (Triticum aestivum L.) plants and to assess the potential of LIF to detect and discriminate between these types of stress. Both long term nitrogen deficiency and pathogen infection resulted in an increase of the ratio of fluorescence at 686 and 740 nm (F686/F740) accompanied by a reduction of leaf chlorophyll content to approximately 35 μg cm−2. A linear negative correlation between chlorophyll content and F686/F740 ratio (r= 0.78) was found for leaves with chlorophyll content ranging between 17 and 52 μg cm−2. Since chlorophyll breakdown appeared an unspecific symptom to both nitrogen deficiency and pathogen infection, it was not possible to discriminate between these types of stress only by means of the F686/F740 ratio. Specific for the pathogen-infected leaves was a large heterogeneity in the records of their spectral parameters caused by inhomogeneous, discrete lesions of fungi infection. Nitrogen-deficient plants with homogeneous reduction in chlorophyll content showed, in contrast, more uniform readings of the spectral parameters. Thus, mildew- and rust-infected plants, grown under sufficient nitrogen fertilisation could be distinguished from those grown under reduced nitrogen supply by the higher variance of their spectral readings. The simultaneous scanning multipoint mode measurements of LIF and laser light reflection characteristics with parallel estimation of their heterogeneity is proposed for the discrimination between nitrogen deficiency and pathogen infection under field conditions.  相似文献   
10.
Drosophila suzukii, commonly known as the spotted-wing Drosophila, is an invasive polyphagous fruit pest, which has emerged as a global threat to agriculture in the Americas and in Europe. Due to the rapid spread, great economic losses and its pest behavior, D. suzukii represents a powerful model for invasion biology and pest management studies. However, its current European distribution, invasion routes and levels of genetic diversity in populations of D. suzukii are poorly understood. We present the first report of D. suzukii from Ukraine, with the invasion likely occurring close to 2014. The pattern of genetic variation at cytochrome oxidase I among D. suzukii populations from Europe, USA and Asia reveals comparatively high genetic diversity in the Ukrainian population of this pest species, suggesting a complex invasion scenario from multiple sources. Further monitoring patterns of genetic variation across space and time, to better understand the invasion routes of this invasive insect pest, will be an essential part for developing successful pest management strategies.  相似文献   
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