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121.
Farid Khallouki Roswitha Haubner Gerhard Erben Cornelia M. Ulrich Robert W. Owen 《Food chemistry》2012
Mirabelle plums represent a famous fruit from the Lorraine region, however little is known about their phytochemical composition. The oil of the fruit contained predominantly oleic acid (59%) and linoleic acid (29%). The total content of phenolic antioxidants in the whole fruits was 5.338 g/kg with 456 mg/kg (9%), 701 mg/kg (13%) and 4159 mg/kg (78%) detected in the peels, flesh and pits respectively. The peels contained solely 3,4-dihydroxybenzoic acid (270 mg/kg) and rutin (186 mg/kg), the flesh exclusively echinoids (723 mg/kg), whereas the pits contained a rich variety of phenolic compounds (4.2 g/kg) dominated by amygdalin (3.8 g/kg), but with significant contributions from vanillin (102 mg/kg), guajacyl-glycerin-coniferyl aldehyde isomers (87 mg/kg), dehydro-diconiferyl aldehyde (52 mg/kg), and vanillin diglucoside (48 mg/kg). Of the major phenolic compounds tested across a range of in vitro assays, rutin was the superior antioxidant. 相似文献
122.
Multifunctional iron-carbon nanocomposites through an aerosol-based process for the in situ remediation of chlorinated hydrocarbons 总被引:1,自引:0,他引:1
Zhan J Kolesnichenko I Sunkara B He J McPherson GL Piringer G John VT 《Environmental science & technology》2011,45(5):1949-1954
Spherical iron-carbon nanocomposites were developed through a facile aerosol-based process with sucrose and iron chloride as starting materials. These composites exhibit multiple functionalities relevant to the in situ remediation of chlorinated hydrocarbons such as trichloroethylene (TCE). The distribution and immobilization of iron nanoparticles on the surface of carbon spheres prevents zerovalent nanoiron aggregation with maintenance of reactivity. The aerosol-based carbon microspheres allow adsorption of TCE, thus removing dissolved TCE rapidly and facilitating reaction by increasing the local concentration of TCE in the vicinity of iron nanoparticles. The strongly adsorptive property of the composites may also prevent release of any toxic chlorinated intermediate products. The composite particles are in the optimal range for transport through groundwater saturated sediments. Furthermore, those iron-carbon composites can be designed at low cost, the process is amenable to scale-up for in situ application, and the materials are intrinsically benign to the environment. 相似文献
123.
Florian Stieglitz Ralf Gerhard Rabea Hnig Klaudia Giehl Andreas Pich 《International journal of molecular sciences》2022,23(8)
A Clostridioides difficile infection (CDI) is the most common nosocomial infection worldwide. The main virulence factors of pathogenic C. difficile are TcdA and TcdB, which inhibit small Rho-GTPases. The inhibition of small Rho-GTPases leads to the so-called cytopathic effect, a reorganization of the actin cytoskeleton, an impairment of the colon epithelium barrier function and inflammation. Additionally, TcdB induces a necrotic cell death termed pyknosis in vitro independently from its glucosyltransferases, which are characterized by chromatin condensation and ROS production. To understand the underlying mechanism of this pyknotic effect, we conducted a large-scale phosphoproteomic study. We included the analysis of alterations in the phosphoproteome after treatment with TcdA, which was investigated for the first time. TcdA exhibited no glucosyltransferase-independent necrotic effect and was, thus, a good control to elucidate the underlying mechanism of the glucosyltransferase-independent effect of TcdB. We found RAS to be a central upstream regulator of the glucosyltransferase-independent effect of TcdB. The inhibition of RAS led to a 68% reduction in necrosis. Further analysis revealed apolipoprotein C-III (APOC3) as a possible crucial factor of CDI-induced inflammation in vivo. 相似文献
124.
Reactivity characteristics of nanoscale zerovalent iron--silica composites for trichloroethylene remediation 总被引:1,自引:0,他引:1
Zheng T Zhan J He J Day C Lu Y McPherson GL Piringer G John VT 《Environmental science & technology》2008,42(12):4494-4499
Spherical silica particles containing nanoscale zerovalent iron were synthesized through an aerosol-assisted process. These particles are effective for groundwater remediation, with the environmentally benign silica particles serving as effective carriers for nanoiron transport. Incorporation of iron into porous sub-micrometer silica particles protects ferromagnetic iron nanoparticles from aggregation and may increase their subsurface mobility. Additionally, the presence of surface silanol groups on silica particles allows control of surface properties via silanol modification using organic functional groups. Aerosolized silica particles with functional alkyl moieties, such as ethyl groups on the surface, clearly adsorb solubilized trichloroethylene (TCE) in water. These materials may therefore act as adsorbents which have coupled reactivity characteristics. The nanoscale iron/silica composite particles with controlled surface properties have the potential to be efficiently applied for in situ source depletion and in the design of permeable reactive barriers. 相似文献
125.
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127.
Guhling O Kinzler C Dreyer M Bringmann G Jetter R 《Journal of chemical ecology》2005,31(10):2323-2341
Primary plant surfaces, covered with cuticles consisting of cutin and waxes, are important substrates for interaction with
insects. The composition of leaf surfaces of the myrmecophilic plant Macaranga tanarius was studied. The prenylated flavanone nymphaeol-C was identified in surface extracts and was localized exclusively in glandular
trichomes on the abaxial leaf side. The epidermal pavement cells surrounding these trichomes were covered with a smooth film
of epicuticular wax from which few small wax crystals protruded. The epicuticular wax amounted to approximately 8 μg cm−2, corresponding to 85% of the wax load on the adaxial as well as the abaxial leaf sides. The epicuticular wax mixtures from
both leaf surfaces contained more than 70% primary alcohols, 14% fatty acids, 2% aldehydes, and traces of alkyl acetates,
with chain lengths ranging from C20 to C38. In contrast, the intracuticular wax layer was largely dominated by triterpenoid alcohols α-amyrin, β-amyrin, and lupeol.
Consequently, these characteristic compounds are not available for direct contact with insects on the plant surface. 相似文献
128.
Michael Rozumek Peter Majewski Heike Schluckwerder Fritz Aldinger Klaus Künstler Gerhard Tomandl 《Journal of the American Ceramic Society》2004,87(9):1795-1798
Ceramics of the melilite-type compound La1+ x Sr1− x Ga3 O7−δ were prepared by conventional ceramic processing. Samples prepared represented the entire homogeneity region of the phase (i.e., x =−0.15 to 0.60). Electrochemical characterization under variable temperature and atmospheric conditions in the vicinity of air entailed four-point direct-current conductivity measurements and electromotive force measurements. La1+ x Sr1− x Ga3 O7−δ samples exhibited a p -type behavior with generally increased conductivity with increased substitution of lanthanum for strontium, which reached a saturation value of ∼10−1 S·cm−1 at 950°C. 相似文献
129.
Pyrylium Compounds. 38. About the Ring Transformation of 2,4,6-Triarylthiopyrylium Salts by Acetic Acid Anhydride to Arylbenzenes and Thiobenzophenones 2,4,6-Triarylthiopyrylium salts 5 react in the presence of an appropriate condensing agent (sodium acetate, carbonate, methoxide, tert-butoxide or potassium acetate) with acetic acid anhydride to yield arylbenzenes 3 and thiobenzophenones 6 . This ring transformation represents the first example of the conversion of the moiety into the thiocarbonyl group Under the same conditions 3,5-dimethyl-2,4,6-triphenylthiopyrylium perchlorate ( 13 ) forms via [1,5]-sigmatropic rearrangement the thiobenzophenone 15 . The structure of the new compounds 6 was proved by spectroscopic methods as well as by degradation reactions. Thus, hydrogen peroxide converts 6a to the known benzophenone 4 . Alkaline saponification gives the 2-hydroxy-benzophenone 8 , whereas heating with hydrochloric acid causes a selective cleavage of the acetoxy group to the 2-hydroxy-thiobenzophenone 7 . 相似文献
130.
Olefinreaktionen in Gegenwart wolfram- und molybdänhaltiger Katalysatorsysteme vom Ziegler-Natta-Typ
Jrg Beger Regina Sass Gerhard Zimmermann 《Advanced Synthesis \u0026amp; Catalysis》1978,320(2):283-290
Reactions of Alkenes in the Presence of Tungsten- and Molybdenum-containing Ziegler-Natta-Catalysts In connection with investigations of reactions of alkenes under the conditions of metathesis we studied the reactions of a mixture of 2-pentene/toluene in presence of the catalytic systems WCl6/EtAlCl2 and MoCl5/EtAlCl2 in homogeneous liquid phase. Alkylation of toluene, metathesis of 2-pentene and also indirect isomerisation of double bonds have been determined in dependence of the molar proportions of 2-pentene/MeClx, toluene/2-pentene, and MeClx/EtAlCl2, the addition order (“formation”) of reactants, the “building time” of catalytic system and the reaction time. Compositions of the reaction mixtures have been determined by GLC. 相似文献