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51.
Gonec T Bobal P Sujan J Pesko M Guo J Kralova K Pavlacka L Vesely L Kreckova E Kos J Coffey A Kollar P Imramovsky A Placek L Jampilek J 《Molecules (Basel, Switzerland)》2012,17(1):613-644
In this study, a series of thirty-five substituted quinoline-2-carboxamides and thirty-three substituted naphthalene-2-carboxamides were prepared and characterized. They were tested for their activity related to the inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. Primary in vitro screening of the synthesized compounds was also performed against four mycobacterial species. N-Cycloheptylquinoline-2-carboxamide, N-cyclohexylquinoline-2-carboxamide and N-(2-phenylethyl)quinoline-2-carboxamide showed higher activity against M. tuberculosis than the standards isoniazid or pyrazinamide and 2-(pyrrolidin-1-ylcarbonyl)quinoline and 1-(2-naphthoyl)pyrrolidine expressed higher activity against M. kansasii and M. avium paratuberculosis than the standards isoniazid or pyrazinamide. The most effective antimycobacterial compounds demonstrated insignificant toxicity against the human monocytic leukemia THP-1 cell line. The PET-inhibiting activity expressed by IC(50) value of the most active compound N-benzyl-2-naphthamide was 7.5 μmol/L. For all compounds, the structure-activity relationships are discussed. 相似文献
52.
Milo S. Jovanovi Nemanja Krgovi Katarina avikin Jelena
ivkovi 《Molecules (Basel, Switzerland)》2022,27(21)
The residue after sieving (“dust”) from the willow gentian underground parts is an unexploited herbal tea by-product, although it contains valuable bioactive compounds. Cyclodextrins as efficient green co-solvents, cage molecules, and multifunctional excipients could improve the extraction and contribute to the added value of the resulting extracts. The objective of this study was to determine the optimal conditions for the extraction of gentiopicroside, isogentisin, and total phenolics (TPC) from willow gentian “dust” using ultrasound-assisted water extraction coupled with hydroxypropyl-β-cyclodextrin (HPβCD). The influence of extraction temperature (X1: 20–80 °C), time (X2: 20–50 min), and HPβCD concentration (X3: 2–4% w/v) was analyzed employing the response surface methodology (RSM). The optimal extraction conditions for simultaneously maximizing the extraction yield of all monitored responses were X1: 74.89 °C, X2: 32.57 min, and X3: 3.01% w/v. The experimentally obtained response values under these conditions (46.96 mg/g DW for gentiopicroside, 0.51 mg/g DW for isogentisin, and 12.99 mg GAE/g DW for TPC) were in close agreement with those predicted, thus confirming the suitability and good predictive accuracy of the developed RSM models. Overall, the developed extraction system could be an applicable alternative strategy to improve the extraction of bioactive compounds from the underutilized “dust” of willow gentian underground parts. 相似文献
53.
Nepomuceno Thyago Celso Cavalcante Santiago Katarina Tatiana Marques Daraio Cinzia Costa Ana Paula Cabral Seixas 《Annals of Operations Research》2022,316(2):1349-1382
Annals of Operations Research - This work discusses the issue on how to include data about property and violent crimes in the production technology for the assessment of police technical... 相似文献
54.
Stefan Andersson-Engels Jaro Ankerst Jonas Johansson Katarina Svanberg Sune Svanberg 《Photochemistry and photobiology》1993,57(S1):978-983
Abstract— Laser-induced fluorescence was used to characterize the localization of intravenously administered ben-zoporphyrin derivative-monoacid (BPD-MA) 3 h postinjection in different rat tissue types, including an induced experimental malignant tumor. A comparison of the fluorescence properties and the demarcation potential between the newer sensitizer BPD-MA and four other substances, hematoporphyrin (HP), polyhematoporphyrin ester (PHE), tetrasulfonated phthalocyanine (TSPc) and the commercially available Photofrin earlier investigated, is included. The fluorescence light was induced with a nitrogen laser, emitting at 337 nm. The fluorescence spectrum in the region380–750 nm was analyzed by a polychromator equipped with a diode array detector. The demarcation potential between tumor and surrounding tissue in terms of fluorescence signal for the tumor model used was 2:1 for BPD-MA. In comparison with the other drugs, HP shows about the same demarcation potential, whereas Photofrin and PHE exhibit about 3 times better and TSPc about 1.5 times better demarcation. By also employing the endogenous tissue fluorescence signature the contrast was enhanced by a factor of about 2 for each of the five drugs. 相似文献
55.
Ernst Kupfer Katarina Neupert-Laves Max Dobler Walter Keller-Schierle 《Helvetica chimica acta》1982,65(1):3-12
The Avileurekanoses A and C and Further Degradation Products of the Avilamycins A and C Alkaline hydrolysis of the orthosomycin antibiotics, avilamycins A ad C products similar t those earlier described for flambamycin. Among these avileurekanose c ( 15 ) became of particular importance because its acetate prisms suitable for an X-ray structural determination. For the avilamycins A and C structural formulae 2 and 3 , respectively, can now be drawn, in which only the configuration at C (16), one out of 32 asymmetric C-atoms, is not yet determined. 相似文献
56.
Katarina PETKOVI? 《数学学报(英文版)》2015,31(8):1339-1347
The main goal of this paper is to establish necessary and sufficient conditions for a matrix A ∈((lp)T,l∞), where T is an arbitrary triangle, 1 ≤ p ≤∞, to be a compact operator. In the past,only sufficient conditions were established in almost all of those cases, by using the Hausdorff measure of noncompactness. We improve those results by applying another method for the characterizations of compact linear operators between BK spaces. 相似文献
57.
58.
Nataša Lilek Andreja Kandolf Borovšak Jasna Bertoncelj Katarina Vogel Mikuš Marijan Nečemer 《X射线光谱测定》2022,51(3):186-197
Bee pollen contains proteins, amino acids, carbohydrates, fats, fatty acids, vitamins, polyphenols, and mineral nutrients that make it useful as a good nutritional supplement in the human diet. It has the richest elemental composition among bee products which is not uniform and consequently varies greatly depending on botanical and geographical origin. In polyfloral and selected monofloral bee pollen samples: sweet chestnut, maple, dandelion, rapeseed, flowering ash, buckwheat, common ivy, and plantain, the concentrations of P, S, Cl, K, Ca, Mn, Fe, Zn, Br, Rb, and Sr were determined. A non-destructive energy dispersive X-ray fluorescence spectrometry was used for elemental fingerprinting. The most abundant elements in Slovenian bee pollen are K, P, S, Ca, and Cl followed by Fe, Mn, Zn, Rb, Br, and Sr. Several statistically significant differences in the content of analysed elements were found between studied groups according to the botanical and geographical origin which can be related to soil and plant elemental composition and plant metabolism. The obtained data extend our previous chemical profiling of Slovenian bee pollen and contribute to a more precise evaluation of some essential mineral nutrients in bee pollen to cover recommended dietary allowances in human nutrition. Additionally, this work contributes to a better understanding of mineral nutrient requirements in honey bee nutrition and of the environmental and agricultural impact of this product. 相似文献
59.
60.
Dragica M. Minić Maja T. Šumar-Ristović Đenana U. Miodragović Katarina K. Anđelković Dejan Poleti 《Journal of Thermal Analysis and Calorimetry》2012,107(3):1167-1176
The kinetics of multi-step thermal degradation of Co(II) complex with N-benzyloxycarbonyl glycinato ligand [Co(N-Boc-gly)2(H2O)4]·2H2O, in non-isothermal conditions was studied using isoconversional and non-isoconversional methods. The degradation of complex
occurs in three well-separated steps involving the loss of water molecules in first step followed by two degradation steps
of dehydrated complex. The dependence of Arrhenius parameters on conversion degree showed that all observed steps of thermal
degradation are very complex, involving more than one elementary step, as can be expected for most solid-state heterogeneous
reactions with solid reactants and solid and gaseous products. It was shown that step 1, corresponding to the dehydration,
involves a series of competitive dehydration steps of differently bound water molecules complicated by diffusion. Second step
involves two parallel reactions related to the loss of two identical C6H5CH2O– ligand fragments complicated by the presence of products in gaseous state. Further degradation in step 3 corresponds to
complex process with a change in the limiting stage, in this case from the kinetic to the diffusion regime, connected with
the presence of gaseous products diffusing through the solid product. 相似文献