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Bałczewski P Bachowska B Białas T Biczak R Wieczorek WM Balińska A 《Journal of agricultural and food chemistry》2007,55(5):1881-1892
The aim of this work was to synthesize chiral ionic liquids as chiral solvents for organic synthesis and to evaluate the phyto(eco)toxicity of the new products and starting N-alkylimidazoles and their potential environmental influence on soil and plants. Chiral ionic liquids containing anions such as Cl-, Br-, TsO-, PF6(-), NO3(-), CF3SO3(-), and (+)- and (-)-C6H5CH(OH)C(O)O- were synthesized using (-)-(1R)-6,6-dimethylbicyclo[3.1.1]hept-2-ene-2-ethyl [(-)-(1R)-nopyl] halides (X = Cl, Br) and tosylate in 62-100% yields. The chloride 7 and the nitrate 13 ionic liquids possessed a toxicity dependent on the applied concentration. The lowest concentration causing a distinct reduction in plant germination/growth was 100 mg/kg. Spring barley better tolerated the ionic liquids (200 mg/kg) than common radish (100 mg/kg). The nitrate liquid did not exhibit an inhibiting effect on the germination ability of seeds. The starting N-methylimidazole used in lower concentrations (1 and 10 mg/kg of soil dry weight) was not phytotoxic, in contrast to higher doses (>1000 mg/kg). 相似文献
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Pim Lindhout Wanda Korta Jeanne Dijkstra 《European journal of plant pathology / European Foundation for Plant Pathology》1988,94(6):307-310
Samenvatting Een methode werd ontwikkeld om de resistentie van in de kas geteelde tomateplanten tegen tomatemozaïek virus (ToMV) te bepalen. Bladeren van een vatbare en een resistente cultivar werden afgesneden en geïnoculeerd met ToMV. Na 6, 10 en 17 dagen werden de geïnoculeerde bladeren getoetst op de aanwezigheid van virus met ELISA en door inoculatie van bladeren vanNicotiana glutinosa. Met beide toetsmethoden kon de virustoename in de vatbare cultivar al vroeg na inoculatie duidelijk worden aangetoond. In de bladeren van de resistente cultivar was een zeer kleine hoeveelheid virus pas laat na de inoculatie aantoonbaar. Met deze methode is het mogelijk om de resistentie tegen ToMV te bepalen, tevens zaad te winnen en landbouwkundige eigenschappen te evalueren, zonder de plant te infecteren. 相似文献
4.
From roots of Taraxacum udum, two new and four known sesquiterpene lactones were isolated, together with five known phenolic compounds. The new compounds were characterized as 11β, 13-dihydrotaraxinic acid and taraxinic acid 6-O-acetyl-β-glucopyranosyl ester by spectroscopic methods, especially 1D and 2D NMR, and by comparison with structurally related compounds. The plant material was shown to be a good source of taraxinic acid derivatives. 相似文献
5.
Teresa Ostaszewska Konrad Dabrowski Katarzyna Czumiska Wanda Olech & Marta Olejniczak 《Aquaculture Research》2005,36(12):1167-1176
The present study evaluated the performance of two commercial diets: AgloNorse (AN) and BioKyowa (BK), and two experimental, formulated diets based on casein (C) or casein plus casein hydrolysates (CH) in rearing of pike‐perch larvae (Sander lucioperca L.). All fish were 5 day old and control group was fed live Artemia nauplii. Fish were sampled periodically for histological comparison of morphological changes in the digestive tracts. Survival of fish fed Artemia nauplii, BK and AN was similar: 54.4%, 50.8% and 52.4%, respectively, while the fish fed formulated diets C and CH showed considerably lower survival: 28.4% and 21.6% respectively. After 5 weeks of rearing, the average body mass of fish ranged from 212±32 mg in Artemia fed group to 53.8±6.8 mg in C diet fed group. A considerable vacuolization of supranuclear zone in enterocytes of posterior intestine was observed in the larvae fed commercial diets. No anomalies in liver development were found. Hepatocytes of fish fed BK diet showed larger glycogen storage areas, compared with those occupied by lipids. The highest zymogen accumulation of pancreatic cytoplasm was observed in fish fed Artemia. In fish fed C and CH diets, anomalies in digestive system development were indicated by lower and less numerous intestinal folds, smaller hepatocytes, retarded development of gastric glands, and in CH group – also local fatty degeneration of liver. 相似文献
6.
Mieczys?aw?Kowalski Wanda?Ma?ekEmail author Jadwiga?Czopska-Dolecka Ma?gorzata?Szlachetka 《Biology and Fertility of Soils》2004,39(4):292-294
Using Tn5 mutagenesis of lysogenic Sinorhizobium meliloti strain L5–30 (L54), three neomycin-resistant transconjugants differing in phage-resistance profiles were isolated. Two of them increased the dry weight of plants and were capable of establishing root nodules, whereas the third one was ineffective. The bacterium-phage interaction did not have observable consequences in the Medicago sativa - S. meliloti symbiosis because it did not affect the number of nodules on M. sativa or plant dry weight. 相似文献
7.
Hong D Gupta R Ancliff P Atzberger A Brown J Soneji S Green J Colman S Piacibello W Buckle V Tsuzuki S Greaves M Enver T 《Science (New York, N.Y.)》2008,319(5861):336-339
Understanding cancer pathogenesis requires knowledge of not only the specific contributory genetic mutations but also the cellular framework in which they arise and function. Here we explore the clonal evolution of a form of childhood precursor-B cell acute lymphoblastic leukemia that is characterized by a chromosomal translocation generating a TEL-AML1 fusion gene. We identify a cell compartment in leukemic children that can propagate leukemia when transplanted in mice. By studying a monochorionic twin pair, one preleukemic and one with frank leukemia, we establish the lineal relationship between these "cancer-propagating" cells and the preleukemic cell in which the TEL-AML1 fusion first arises or has functional impact. Analysis of TEL-AML1-transduced cord blood cells suggests that TEL-AML1 functions as a first-hit mutation by endowing this preleukemic cell with altered self-renewal and survival properties. 相似文献
8.
The structural and electronic properties of the La@C(82) fullerene have been investigated by means of the Car-Parrinello method, which is based on the local density approximation of the density functional theory. The topological arrangement of the C(82) cage was assumed to be a C(3v) symmetry isomer. Three configurations were considered, one with the lanthanum atom at the center of the cluster, one with it along the threefold axis, and one with it at a low-symmetry, highly coordinated site. The structure was fully relaxed and it was found that the last of these configurations is energetically preferred. In this position, the lanthanum atom is nearly in a La(3+) state and the unpaired electron is somewhat delocalized on the cage, in agreement with available experimental data. This arrangement suggests that the chemical shifts of the 5s and 5p lanthanum states can be used as a structural probe and as a way of further validating this picture. It is argued that this conclusion is not affected by the assumed fullerene structure. 相似文献
9.
Munro LJ Curioni A Andreoni W Yeretzian C Watzke H 《Journal of agricultural and food chemistry》2003,51(10):3092-3096
Aroma is central to a pleasurable eating/drinking experience but is one of the most labile components of food. Coffee is an outstanding example. Attempts to avoid or control aroma degradation are often frustrated by ignorance of the microscopic mechanisms that are responsible for it. One of the processes most frequently invoked is radical formation, yet the identity of the radicals and their involvement in aroma degradation are poorly understood at the molecular level. Here a step forward in the fundamental understanding of this complex problem is taken by identifying the most relevant radicals and their products using first-principles calculations. Over 100 radicals originating from key aroma compounds found in coffee and other foods have been studied and classified according to an unambiguous criterion: their thermodynamic stability relative to common radical sources. This classification scheme predicts that most aroma molecules are resistant to both peroxidation and attack from phenolic antioxidants but are unstable with respect to radicals such as .OH. Dimers--generated from radical reactions--were also considered, and the most volatile species, which may further contribute to coffee aroma degradation, were focused on. Those--which are very few indeed--that have this potential have been identified. 相似文献
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