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101.
102.
Investigations on Potato Pulp as a Dietary Fiber Source. Composition of Potato Pulp After Influence of Pectinases and Cellulases and Enzymatic Degradation of Starch. The composition of alcohol insoluble substances (AIS) of potato pulp have been investigated after succesive degradation with different pectolytic and cellulolytic enzymes followed by starch degrading enzymes. The pretreatment with pectinase/cellulase combinations has a significant influence on the amount and the properties of the residues after starch degradation. Furthermore the most important changes in the composition were found in the receiving residues after action of amylolytic enzymes. A correlation exists between the content of residual starch in the residues and the action of the cell wall degrading enzymes. The amount of residual starch correlates negatively with the intensity of cell wall degradation. The enzymatic susceptibility of starch depends on the damage of cell wall of potato pulp, especially on the degree of degradation of the cellulose. The water binding capacity decreases intensively after action of pectinase/cellulase combinations. The treatment with amylolytic enzymes causes only a negligible variation of the water binding capacity. 相似文献
103.
Jrg Hofmann Gerhard Just Wilhelm Pritzkow 《Advanced Synthesis \u0026amp; Catalysis》1991,333(1):67-71
The title compounds were prepared from 2,4-dioxohexahydro-triazine (DHT) and the corresponding acid chlorides in the presence of sulphuric acid. They are active acylating agents against piperidine in dioxane as the solvent. Only the diacyl derivatives of DHT with acyl chain lengths up to C6 react with aqueous solutions of sodium perborate forming the corresponding peroxy acids. 相似文献
104.
Flavins and Chinamoyl Derivatives in Relation to the Light-induced Leaf Opening in Albizia julibrissin In search of blue-light photoreceptors for light-induced leaf opening we isolated from the aqueous extract of Albizia julibrissin Durazz. two flavins by adsorption on XAD-4 and separation with HPLC. One sample was identified as riboflavin 1a. In the hydrolysate of the second flavin fraction we found another dimethylisoalloxazine with a C5-side chain. Furthermore we isolated the cinnamoyl derivatives 3-O-(4-hydroxy-trans-cinnamoyl) quinic acid 2 and 3-O-(3,4-dihydroxy-trans-cinnamoyl)-4-O-malonyl-quinic acid 3 which formed charge transfer complexes with the flavins in the XAD-fraction. As a model complex we examined the absorption behaviour of the complex between riboflavin and chlorogenic acid. Using the association constant, we calculated the absorption spectrum and could show that a complex between a flavin and a phenolic compound is a possible blue-light photoreceptor for the light-induced leaf opening in Albizia julibrissin. 相似文献
105.
Dr. Markella Konstantinidou Francesca Magari Fandi Sutanto Dr. Jörg Haupenthal Dr. Varsha R. Jumde Dr. M. Yagiz Ünver Prof. Dr. Andreas Heine Dr. Carlos Jamie Camacho Prof. Dr. Anna K. H. Hirsch Prof. Dr. Gerhard Klebe Prof. Dr. Alexander Dömling 《ChemMedChem》2020,15(8):680-684
Pharmacophore searches that include anchors, fragments contributing above average to receptor binding, combined with one-step syntheses are a powerful approach for the fast discovery of novel bioactive molecules. Here, we are presenting a pipeline for the rapid and efficient discovery of aspartyl protease inhibitors. First, we hypothesized that hydrazine could be a multi-valent warhead to interact with the active site Asp carboxylic acids. We incorporated the hydrazine anchor in a multicomponent reaction and created a large virtual library of hydrazine derivatives synthetically accessible in one-step. Next, we performed anchor-based pharmacophore screening of the libraries and resynthesized top-ranked compounds. The inhibitory potency of the molecules was finally assessed by an enzyme activity assay and the binding mode confirmed by several soaked crystal structures supporting the validity of the hypothesis and approach. The herein reported pipeline of tools will be of general value for the rapid generation of receptor binders beyond Asp proteases. 相似文献
106.
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
107.
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
108.
European Journal of Wood and Wood Products - Zur Beurteilung der Verteilung der Spandicke in Spänegemischen wurde das bekannte Verfahren der Häufigkeitsuntersuchung angewendet. Dabei... 相似文献
109.
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
110.
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