Go toArchive
Browse byFacets
Bookbag ( 0 )
Facet   Publication Year 1996  [X]
Facet   section ZfN Section C:Volume 051  [X]
Results  129 Items
Sorted by   
Publication Year
1996[X]
61Author    MarkusD. Urm Abc, Michael Hausm, Klaus Aldinger3, Horst Ludwigbc, Christoph CremRequires cookie*
 Title    Painting of Human Chromosome 8 in Fifteen Minutes  
 Abstract    The technique of chromosome-m-s/ta suppression (ClSS)-hybridization (chrom osome painting) has now been well established. However, all standard protocols so far require long renaturation times (typically 12 hours and more). Here, we describe a new, extremely fast pro­ tocol for chromosome painting using a commercially available, directly fluorescence labelled probe for chro­ mosome 8. The hybridization conditions used omit sepa­ rate preannealing procedures and denaturing chemical agents. The renaturation time required for chromosome painting was reduced to 15 minutes. In addition, most washing steps were eliminated. A s a consequence, the entire painting procedure was feasible in less than half an hour. 
  Reference    Z. Naturforsch. 51c, 435 (1996); received January 29/March 1 1996 
  Published    1996 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0435_n.pdf 
 Identifier    ZNC-1996-51c-0435_n 
 Volume    51 
62Author    P. He, A. Radunz, K. P. Bader, G. H. SchmidRequires cookie*
 Title    Influence of C 0 2 and S 0 2 on Growth and Structure of Photosystem II of the Chinese Tung-Oil Tree Aleurites montana  
 Abstract    Three months old plants of the Chinese tung-oil tree Aleurites montana were cultivated for 4 months in air containing an increased amount o f 700 ppm C 0 2. During the exposure to 700 ppm C 0 2 the plants exhibited a considerably stronger growth (3 0 -4 0 %) in compari­ son to the control plants (grown in normal air). In these C02-plants during the entire analyz­ ing period the amount of soluble proteins, of soluble sugars and the chlorophyll content were lower than in control plants. The protein content, referred to leaf area, increased during this time in both plant types by approx. 50% but with a different time course. The increase is faster in C02-plants compared to control plants, and ends up with similar values in both plants after 4 months. No difference is seen between sun and shade leaves. The chlorophyll content in both sun and shade leaves is 20% lower in C02-plants. Whereas the chlorophyll content in sun leaves stays constant during developm ent, it has increased in shade leaves by 20% at the end of the 4 months period. The content of soluble sugars is lower in C 0 2-plants compared to control plants. The difference is bigger in sun leaves than in shade leaves. The ribulose 1.5-bisphosphate carboxylase/oxygenase content almost doubles within the experimentation period, but seem s to be subject to large variations. C02-plants contain in general less ribulose 1.5-bisphosphate carboxylase/oxygenase than control plants. The content of coupling factor of photophosphorylation is 20% lower in C02-plants when compared to control plants and remains during developm ent more constant in C02-plants. The molecular structure of the photosystem II-complex undergoes under the influence o f the increased C 0 2-content a quantitative modification. The light harvesting com plex (LHCP) and the ex­ trinsic peptide with the molecular mass of 33 kDa increase in C02-plants. Gassing with S 0 2 (0.3 ppm in air) leads to a strong damage of the plants. The damaging influence is already seen after 6 days and leads to a partial leaf-shedding o f the tree. In the visually still intact remaining leaves the chlorophyll content referred to unit leaf area decreases by 63%, that of soluble sugars by 65%, the content of soluble proteins and that of Rubisco decrease by 26% and 36% respectively. The light harvesting complex and the chloro-phyll-binding peptides (43 and 47 kD a) increase whereas the extrinsic peptides decrease. It looks as if the simultaneous application of S 0 2 (0.3 ppm) and increased C 0 2 (700 ppm) releaves the damaging effect of S 0 2. Plant growth does not exhibit a difference in comparison to control plants. Soluble proteins and chlorophyll increase by 27% and 33% and the ribulose 1.5-bisphosphate carboxylase/oxygenase content as well as that o f soluble sugars increases by 18 respectively 14%. The peptide composition o f photosystem II shows a quantitative modification. The LHCP increases and the chlorophyll-binding peptides and the peptides with a molecular mass smaller than 24 kDa are reduced. The quantity of extrinsic peptides appears unchanged. Ribulose 1,5-bisphosphate carboxylase/oxygenase and the CFj-complex o f Aleurites are immunochemically only partially identical to the corresponding enzymes of Nicotiana taba­ cum as demonstrated by tandem-cross-immune electrophoresis. 
  Reference    Z. Naturforsch. 51c, 441 (1996); received May 7/May 16 1996 
  Published    1996 
  Keywords    Aleurites montana, CO2, SO2, S02-D am age, LHCP-Complex, Photosystem II-Complex, C F r Complex 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0441.pdf 
 Identifier    ZNC-1996-51c-0441 
 Volume    51 
63Author    Grzegorz JackowskiRequires cookie*
 Title    The Subcomplex Organization of the Major Chlorophyll «/6-Protein Light- Harvesting Complex of Photosystem II (LHCII) in Barley Thylakoid Membrane  
 Abstract    The major chlorophyll «/b-protein light-harvesting complex o f photosystem II (LHCII) isolated form barley photosynthetic membrane was shown to contain five major polypeptides only two o f which (26.7 and 25.6 kDa) were found to be its true constituents as judged by the ability to migrate as oligomers in various analytical systems. When analyzed by a vertical-bed non-denaturing isoelectric focusing the LHCII was resolved into five trimeric subcom­ plexes (designated 1 -5 in order of decreasing p i) containing either only 26.7 kDa polypep­ tide (subcom plexes 1 and 2) or 26.7 and 25.6 kDa ones associated at 2:1 ratio (subcom plexes 3 -5) . The polypeptide of 26.7 kDa could be split by denaturing isoelectric focusing into fifteen molecular forms while nine molecular species were found to be constituents of 25.6 kDa polypeptide. The subcom plexes 1 -5 contained molecular forms of one or both polypep­ tides associated in sets of 7 -9 . Our findings favour the view that the apoproteins of LHCII are much more heterogenous than thought before. 
  Reference    Z. Naturforsch. 51c, 454 (1996); received November 23 1995/March 4 1996 
  Published    1996 
  Keywords    Barley, Isoelectric Focusing Light Harvesting Complex Polypeptide Subcomplex, Trimer 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0454.pdf 
 Identifier    ZNC-1996-51c-0454 
 Volume    51 
64Author    Grzegorz JackowskiRequires cookie*
 Title    Senescence-Related Changes in the Subcomplex Arrangement of the Major Light-Harvesting Chlorophyll a/b-Protein Complex of Photosystem II (LHCII) as Influenced by Cytokinin  
 Abstract    The major light-harvesting chlorophyll a /b -protein complex of photosystem II (LHCII) from fresh barley leaves could be resolved by non-denaturing IEF into five trimeric subcom­ plexes designated 1 -5 in order of decrasing pi value. IEF-based analysis of PSII particles isolated from leaves in which the processes of senescence were induced by detachement and dark-incubation in the presence of water for 0 -8 days let us reveal that substantial rearrangements of LHCII organization took place throughout the course of senescence com ­ prising a step-wise decline in relative abundance of subcom plexes 1 -3 (down to 0-58% of the initial abundance during 8 days of aging) and an increase in the relative abundance of the subcom plexes 4 and 5. Using SDS-PAGE and immunoblot analysis it was shown that the rearrangements were linked to the changes in the relative levels of LHCII apoproteins i.e. 26.7 and 25.6 kDa ones. The changes comprised the preferential disappearance of the 26.7 kDa polypeptide and an enrichment of 25.6 kD a one and most probably reflect the hetero­ geneity among LHCII apoproteins concerning their stability under the conditions of chi loss. Kinetin was able to repress the senescence-related rearrangements in LHCII subcomplex organization at late stages of aging (5 -8 days) by preventing over this time period the disap­ pearance of 26.7 kD a polypeptide and the enrichement of 25.6 kDa one. 
  Reference    Z. Naturforsch. 51c, 464 (1996); received Novem ber 23 1995/ 
  Published    1996 
  Keywords    Aging, Barley, Isoelectric Focusing, Polypeptide, Rearrangement 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0464.pdf 
 Identifier    ZNC-1996-51c-0464 
 Volume    51 
65Author    Hans Rausch, GeorgG. GrossRequires cookie*
 Title    Preparation of [14C]-LabeIled l,2,3,4,6-Penta-0-Gal!oyl-/?-D-Glucose and Related Gallotannins  
 Abstract    [U -14C]-Labelled 1,2,3,4,6-penta-O-galloyl-ß-D-glucose was prepared by photoassimilation of 14C 0 2 with leaves from staghorn sumac (Rhus typhina) in the presence of the herbicide glyphosate. Extracts of the plant material were partitioned against ethyl acetate and chro­ matographed on Sephadex LH-20, yielding a series o f crude tri-to decagalloylglucoses. The pentagalloylglucose fraction among these was further purified by HPLC to >99% purity and a specific radioactivity of 130 kBq (3.5 fiCi) per fimol. The ratio of the radioactivities in the glucose and galloyl moieties, respectively, suggested a uniform labelling pattern of the product. 
  Reference    Z. Naturforsch. 51c, 473 (1996); received February 8/March 8 1996 
  Published    1996 
  Keywords    [I4C]l, 2, 3, 4, 6-Penta-0-galloyl-ß-D-glucopyranose, Gallotannins, Photosynthesis, Rhus typhina, Staghorn Sumac 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0473.pdf 
 Identifier    ZNC-1996-51c-0473 
 Volume    51 
66Author    Kirstin Feussnera, Andrzej Guranowskib, Susanne Kostkac, ClausW. Asternack3Requires cookie*
 Title    Diadenosine 5',5"'-P1,P4-tetraphosphate (Ap4A ) Hydrolase from Tomato {Lycopersicon esculentum cv. Lukullus) -Purification, Biochemical Properties and Behaviour during Stress  
 Abstract    Peptide Sequence, Phosphonate Analogues of A p4A, Nucleotide Binding Site, Stress D inucleoside 5',5'"-P',P4-tetraphosphate hydrolase (EC 3.6.1.17) has been purified to hom ogeneity from tom ato (Lycopersicon esculentum) cells grown in suspension. The purifica­ tion procedure comprised ammonium sulphate fractionation following five standard chroma­ tography steps and a final chromatography on A p4A-Sepharose. The hom ogeneous hydrolase has a molecular mass of 20 kD a and an isoelectric point of 4.5. The enzyme hydrolyses diadenosine tetraphosphate (A p 4A) asymmetrically to A M P and ATP. A m ong other naturally occurring dinucleoside oligophosphates, A p5A and A p 6A are substrates whereas A p 3A is not. Of various phosphonate analogues tested, the A p ?A ana­ logue, A ppC H 2pCH2ppA, was not cleaved and the A p 3A analogue, A pC H 2C H 2ppA. was a very poor substrate. Enzyme activity is stimulated by 5 mM M g-+ and inhibited by fluoride anion; I50 = 6.25 [.i m . The K m value for A p4A is 0.8 [.i m . The enzyme exhibits a broad pH optimum from pH 6.5 to 9.0. In order to analyze the protein at the molecular level an internal peptide sequence from the hom ogeneous enzyme was identified. Within the sequence of 17 amino acids a kinase II motif as a general part of a conserved sequence of nucleotide binding sites was found. Against the internal peptide sequence a polyclonal antiserum was raised. By investigating the intracellular level o f A p4A hydrolase under different kinds of environmental stress, no changes occurred in response to heat shock. But, heavy metal stress and phosphate depriva­ tion lead to a decrease in A p4A hydrolase. 
  Reference    Z. Naturforsch. 51c, 477 (1996); received January 29/March 4 1996 
  Published    1996 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0477.pdf 
 Identifier    ZNC-1996-51c-0477 
 Volume    51 
67Author    SylviaZ. Apf3, A. Nnette Wunder3, TimmA. Nke3, Dörte Klosterm, Wolfgang Steglichb, Rudong Shanc, Olov Sterner0, W. Erner ScheuerdRequires cookie*
 Title    (+)-10a-Hydroxy-4-muurolen-3-one, a New Inhibitor of Leukotriene Biosynthesis from a Favolaschia Species. Comparison with Other Sesquiterpenes  
 Abstract    Favolaschia Species, Basidiomycetes, Leukotriene Biosynthesis-Inhibitors, (+)-10a-H ydroxy-4-m uurolen-3-one A new inhibitor of leukotriene biosynthesis, (+)-10a-hydroxy-4-muurolen-3-one (1), was isolated from fermentations of Favolaschia sp. 87129. Its structure was established by spectro­ scopic methods. The compound exhibited no antifungal or antibacterial activities. The effects of 1 on leukotriene biosynthesis were compared with (+)-T-cadinol, (-)-3-oxo-T-cadinol, and (+)-3a-hydroxy-T-cadinol, three related sesquiterpenes. 
  Reference    Z. Naturforsch. 51c, 487—4 (1996); received February 14/March 25 1996 
  Published    1996 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0487.pdf 
 Identifier    ZNC-1996-51c-0487 
 Volume    51 
68Author    A. Nnette, W. Under1, TimmA. Nke3, D. Örte Klostermeyerb, Wolfgang SteglichbRequires cookie*
 Title    Lactarane Type Sesquiterpenoids as Inhibitors of Leukotriene Biosynthesis and Other, New Metabolites from Submerged Cultures of Lentinellus cochleatus (Pers. ex Fr.) Karst  
 Abstract    Three known sesquiterpenoids of the lactarane and secolactarane type, deoxylactarorufin A (1), blennin A (2) and blennin C (3), have been obtained from cultures of Lentinellus cochleatus (Basidiom ycetes) together with the new metabolites (Z)-2-chloro-3-(4-m e-thoxyphenyl)-2-propen-l-ol (4) and lentinellone (5), a protoilludane derivative. The struc­ tures were determined by spectroscopic investigations. 1, 2 and 3 are potent inhibitors of leukotriene biosynthesis in rat basophilic leukemia (RBL-1) cells and human peripheral blood leukocytes (PBL). 
  Reference    Z. Naturforsch. 51c, 493—4 (1996); received March 3 March 13 1996 
  Published    1996 
  Keywords    Basidiomycetes, Lentinellus cochleatus, Inhibitors of Leukotriene Biosynthesis, Lactaranes, Protoilludanes 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0493.pdf 
 Identifier    ZNC-1996-51c-0493 
 Volume    51 
69Author    Martin Semara, HeidrunA. Nke3, Wolf-Rüdiger Arendholzb, Robert Veiten0, Wolfgang Steglich0Requires cookie*
 Title    Lachnellins A, B, C, D, and Naphthalene-l,3,8-triol, Biologically Active Compounds from a Lachnellula Species (Ascomycetes)  
 Abstract    In the course of our search for new biologically active metabolites, lachnellin A (1), a metabolite with high cytotoxic and antimicrobial activities, the structurally related lachnellins B. C and D (3, 4, 7), and naphthalene-l,3,8-triol (8), an inhibitor of malate synthase (EC 4.1.3.2), were isolated from submerged cultures o f the ascomycete Lachnellula sp. A 3 2 -8 9 . The antimicrobial, cytotoxic and phytotoxic activities of lachnellin A depended on its reactiv­ ity and could be abolished by the addition of cysteine. The enzyme inhibiting activity of (8) was due to reactive intermediates during melanization and was no longer observed in the presence of serum albumin. In addition, rac-scytalone (9), (+)-fra/7s-3,4-dihydro-3,4,8-trihy-droxy-l(2//)-naphtha!enone (10). 2,5-dihydroxytoluene (11), and (/?)-(-)-5-methylmellein (12) were obtained from the same source and biologically characterized. 
  Reference    Z. Naturforsch. 51c, 500 (1996); received March 1/April 29 1996 
  Published    1996 
  Keywords    Lachnellin A, B, C D Glyoxylate Cycle, N aphthalene-1, 3, 8-triol, Malate Synthase, Melanization, Lachnellula sp 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0500.pdf 
 Identifier    ZNC-1996-51c-0500 
 Volume    51 
70Author    C. Scheick, G. SpitellerRequires cookie*
 Title    Direct Release of Ethylene from Methionine and Methionine Containing Peptides by Action of 13-Hydroperoxy-(9c/.s, ll/r«ws)-octadecadienoic Acid  
 Abstract    Ethylene, M ethionine, Lipid Peroxidation. Lipoxigenase, M ethionylpeptides 13-Hydroperoxy-9m,12/'ran5-octadecadienoic acid (13-LO OH) reacts with methionine and m ethionine-containing peptides in absence of any other reagent by slow release of ethylene. Ethylene was identified by mass spectrometry and quantified by gas chromatography. The amount of ethylene released in a certain time interval depends on the position of the m ethio­ nine residue in the peptide chain. Highest rates of ethylene release were measured with peptides carrying m ethionine at the N-terminus. 13-Hydroperoxy-9c/s,12rra/7.s'-octadecadie-noic acid can be substituted by linoleic acid, lipoxigenase and oxygen. We assume that the instant formation of lipid peroxides after plant injury and the instant release of 'wound ethylene' are related. Since the initiator tR NA in eucaryontic cells always carries a m ethio­ nine, all newly produced proteins contain methionine at the N-terminal position and are therefore sensitive to oxidative damage by hydroperoxides of fatty acids. 
  Reference    Z. Naturforsch. 51c, 513 (1996); received February 12/March 1 1996 
  Published    1996 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0513.pdf 
 Identifier    ZNC-1996-51c-0513 
 Volume    51 
71Author    Satoshi Senoo3, Tetsuji Iida3, Kou Shouda3, Yukiharu Sato3, Nicolausb Beate, Peter Bögerb, Ko Wakabayashi3Requires cookie*
 Title    Enzyme-Modified Phytotoxic Structure of Thiadiazolidine Compounds  
 Abstract    Plant esterase. Glutathione S-Transferase, Thiadiazolidines / Triazolidines, Esters and Free Acids, Isomerization A simple model thiadiazolidine, 5-(4-m ethoxycarbonylmethylthio-phenylimino)-3,4-tetra-methylene-l,3.4-thiadiazolidin-2-one, was synthesized and its structural modification investi­ gated using glutathione S-transferase (GST) and an esterase preparation isolated from Echi-nochloa utilis. The objective is a better understanding of the metabolic activation of peroxidizing thiadiazolidine compounds. The model thiadiazolidine with an ester group (thia­ diazolidine ester) was isomerized by GST to a more phytotoxic triazolidine structure (triazol-idine ester). Both the thiadiazolidine and the more active triazolidine ester were hydrolyzed by Echinochloa esterase to less active free acid compounds. 5-(4-carboxymethylthiophenyli-m ino)-3,4-tetramethylene-l,3,4-thiadiazolidin-2-one (thiadiazolidine acid) and 4-(4-carboxy-methylthiophenyl)-L2-tetram ethylene-1.2.4-triazolidin-3-one-5-thione (triazolidine acid), respectively. The thiadiazolidine acid, however, was only slightly converted into the triazoli­ dine acid in the presence of GST. It is concluded that the thiadiazolidine ester was isomerized in Echinochloa to give the triazolidine acid through the triazolidine ester. Since the triazoli­ dine ester exhibited the highest phytotoxic peroxidizing activity GST is considered as an activating enzyme for phytotoxicity and esterase as a detoxifying enzyme to reduce phyto­ toxic activity. Accordingly, phytotoxic thiadiazolidine-ester type herbicides may be produced by an interplay of isomerizing GST and esterase activity contributing to herbicide selectivity among plant species. 
  Reference    Z. Naturforsch. 51c, 518 (1996); received March 19. 1996 
  Published    1996 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0518.pdf 
 Identifier    ZNC-1996-51c-0518 
 Volume    51 
72Author    A. Kio Kobayashi1, JoK. Myong, Im, Kazuyoshi Kawazu0Requires cookie*
 Title    Uptake and Exudation of Phenolic Compounds by Wheat and Antimicrobial Components of the Root Exudate  
 Abstract    In the course of our study, it was found that phenyl propenoic acid derivatives were readily taken up by wheat. Leaf leachate components were chosen for the feeding experiments and /j-coumaric acid, ferulic acid and caffeic acid were found to be quickly taken up into the plants via the roots. The analytical study revealed that the exudate contained potent antim i­ crobial compounds together with amino acids and sugars. Besides the primary metabolites, 4-hydroxystyrene, 3-methoxy-4-hydroxystyrene and 3-methoxy-4-acetoxystyrene were identified as exudate components from wheat roots in sterile hydroponic culture. This indicates that these antimicrobial components may play a significant role in the defense system as allelochemicals for the rhizosphere. 
  Reference    Z. Naturforsch. 51c, 527—533 (1996); received January 31/ 
  Published    1996 
  Keywords    Decarboxylation, p-Coumaric Acid Ferulic Acid, Caffeic Acid, Uptake, Exudate, Antimicrobial Styrenes 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0527.pdf 
 Identifier    ZNC-1996-51c-0527 
 Volume    51 
73Author    Gerhard Sandmann3, Christian Schneiderb, Peter BögerbRequires cookie*
 Title    A New Non-Radioactive Assay of Phytoene Desaturase to Evaluate Bleaching Herbicides  
 Abstract    A non-radioactive cell-free assay was developed to quantitatively determine inhibition of plant-type phytoene desaturase by bleaching herbicides. A n active desaturase was prepared from an appropriately cloned E. coli transformant. Another E. coli transformant was used to produce the required phytoene. Phytofluene and t-carotene, the products of the desaturase reaction, were either determined by H PL C or optical absorption spectra. Enzyme kinetics and inhibition data for the bleaching tetrazole herbicide W L 1 10547 are presented as an example. 
  Reference    Z. Naturforsch. 51c, 534—538 (1996); received April 26/May 3 1996 
  Published    1996 
  Keywords    Phytoene, Phvtofluene, u-Carotene, Phvtoene Desaturase, in-vitro Assay, /50 Value, W L 110547 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0534.pdf 
 Identifier    ZNC-1996-51c-0534 
 Volume    51 
74Author    L. Kovács3, U. Hegdeb, S. Padhyeb, G. Bernät3, S. Demeter3Requires cookie*
 Title    Effects of Potassium-(picrate)-(18-crown-6) on the Photosynthetic Electron Transport  
 Abstract    The effects of potassium-(picrate)-(18-crown-6) on the electron transport of photosystem II was investigated in isolated pea thylakoids. Low concentrations of the compound inhibited the fast decay of fluorescence yield associated with electron transfer between the primary (Q a) and secondary (Q b) quinone electron acceptor and increased the intermediary level of fluorescence to the Fmax level. The decay half-time of fluorescence yield measured in the presence of D C M U (S2Q A' charge recombination) decreased from about 1.8 s to about 0.3 s in thylakoids treated with potassium-(picrate)-(18-crown-6). W hile the inhibition of electron transport by D C M U gave rise to the appearance of a thermoluminescence band at about + 10°C (S2Q A~charge recombination) addition of potassium-(picrate)-(18-crown-6) resulted in a thermoluminescence band at about -10°C. Increasing concentrations of potassium-(picrate)-(18-crown-6) diminished the fluorescence yield and the -10°C TL band and abolished the Signal II S and Signal I I f E P R signals of the tyrosine-D and tyrosine-Z electron donors, respec­ tively. The phenolic-type inhibitor, potassium picrate had the same effect on thermolumines­ cence and on the tyrosine E P R signals. It is concluded that potassium-(picrate)-(18-crown-6) is a phenolic type inhibitor owing to its picrate constituent. A t low concentrations picrate and potassium-(picrate)-18-crown) not only block the electron transport between Q A and O b but they probably decrease the midpoint redox potential of Q A, as well. A t high concen­ trations they also inhibit the light-induced oxidation of the tyrosine-D and tyrosine-Z donors. 
  Reference    Z. Naturforsch. 51c, 539—547 (1996); received December 22 1995/ 
  Published    1996 
  Keywords    Phenolic Inhibitors, Photosynthesis, Photosystem II, Thermoluminescence, Electron Paramagnetic Resonance 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0539.pdf 
 Identifier    ZNC-1996-51c-0539 
 Volume    51 
75Author    Joachim Wtibert, Ulrike Oster, Wolfhart RüdigerRequires cookie*
 Title    Inhibitors of Chlorophyll Biosynthesis from Bulbs of Gladiolus spp  
 Abstract    Gladiolus spec., Lepidium sativum L., 3-Hydroxybenzoic Acid Methylester, 5-Hydroxymethylfurfural, Gas Chromatography/mass Spectrometry Com pounds extracted with methanol from the bulbs of Gladiolus spp. were tested for inhibition of Chi accumulation in greening cress (Lepidium sativum L.) seedlings. For the biotest, cress seeds were imbibed with water for 8 h and then incubated in the dark with the test solution for 40 h. Chlorophyll accumulation was determined at the end of the subsequent irradiation period of 8 h. Compounds active in this biotest were purified by several chromato­ graphic steps and identified by thin-layer chromatography with staining reactions and by gas chromatography/mass spectrometry. The following compounds were identified and their concentration for 50% inhibition of Chi accumulation determined: sucrose (75 m M) plus glucose (30 m M) , 3-hydroxybenzoic acid methylester (0.49 m M) and 5-hydroxymethylfurfural (6.7 m M) . The inhibitory action was compared with several substituted derivatives of the natural compounds. 
  Reference    Z. Naturforsch. 51c, 548—557 (1996); received April 19/May 2 1996 
  Published    1996 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0548.pdf 
 Identifier    ZNC-1996-51c-0548 
 Volume    51 
76Author    AngelS. Galabova, Tanya Iosifovab, Elka Vassilevab, Ivanka KostovabRequires cookie*
 Title    Antiviral Activity of Some Hydroxycoumarin Derivatives  
 Abstract    Hydroxycoumarin, Esculetin. Antiviral, in vitro Screening Esculetin (6,7-dihydroxycoumarin) and its diacetate exhibited a marked inhibitory effect on Newcastle disease virus replication in cell cultures at concentrations of 36 jam and 62 jam, respectively. These compounds were selected from ten hydroxycoumarin derivatives through an in vitro antiviral screen involving viruses of the picorna-, orthomyxo-, paramyxo-, and herpes virus families. 
  Reference    Z. Naturforsch. 51c, 558—562 (1996); received August 29 1995/April 25. 1996 
  Published    1996 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0558.pdf 
 Identifier    ZNC-1996-51c-0558 
 Volume    51 
77Author    Cabezudo-RiveraM. Reyesa, C. M. Artín3, C. Alarcó, J. De La Lastra3, M. V. Trujillob, M. J. Toro3, Ayuso3Requires cookie*
 Title    Antiulcerogenicity of the Flavonoid Fraction from Erica andevalensis  
 Abstract    Investigations were carried out to determine the antiulcerogenicity of the flavonoid frac­ tion (ethyl acetate extract) of Erica andevalensis Cabezudo-Rivera on gastric ulceration in­ duced by different experimental models. Oral treatment with the ethyl acetate extract and the major flavonoid (myricetin 3-O-D-galactoside) were found to be effective to prevent gastric ulceration induced by cold-restraint stress in rats . Statistically significant ulcer index values with respect to the control group were observed. Mucus content was not increased although it was accompanied by an increase in proteins and hexosamines. In pyloric-ligated animals flavonoids showed a significant reduction in the number and severity of the ulcers. Under the same conditions acidity did not decrease with the flavonic extract and myricetin 3-O-D-galactoside significantly as compared to control. Gastric ulcers induced by oral adm in­ istration of absolute ethanol were reduced by pretreatment with the flavonoid extract of doses from 125 to 250 mg/kg and the isolated flavonoid of 25 mg/kg p.o. However neither the flavonic extract nor the isolated flavonoid induced changes in the amount and glycopro­ tein content of gastric mucus. is considered to be a physiological barrier which plays an important role in protecting gastric mucosa. Material and Methods General procedure Melting point was determined using a micro­ scopy Thermovar HT 1 B l l and is incorrected. U l­ traviolet absorption (U V) and infrared (IR) spectra were measured on a Perkin Elmer Lambda 3 spectrophotometer and a Perkin-Elmer 681 spectrophotometer, respectively. 'H-RM N spectrum was recorded with a Bruker ACTF spec­ trometer at 200 M Hz. El-mass and FAB-mass spectra were obtained with a Kratos MS-80-RFA mass spectrometer at 70 eV. Analytical G C was carried out with a Hewlett Packard 5710A chro­ matograph equipped with a flame ionization de­ tector, using a BP-1 fused silica glass capillary col­ umn (25 m x 0.53 mm) (temperature programmed from 100 to 240°C at 2°C m i n 1). The temperatures of the injector and the detector were kept at 250°C and 300°C, respectively. Carrier gas was Helio and 
  Reference    Z. Naturforsch. 51c, 563—569 (1996); received January 29/March 6 1996 
  Published    1996 
  Keywords    Erica andevalensis, Flavonoids Gastric mucus Gastric Ulceration, Antiulcerogenicity 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0563.pdf 
 Identifier    ZNC-1996-51c-0563 
 Volume    51 
78Author    M.J M Artín Calero, C.La Casa, V. Motilva, A. L. Ópez, C. Alarcó, La De, LastraRequires cookie*
 Title    Healing Process Induced by a Flavonic Fraction of Bidens aurea on Chronic Gastric Lesion in Rat. Role of Angiogenesis and Neutrophil Inhibition  
 Abstract    The aim of this study was to elucidate the mechanism of the healing process mediated by the flavonic fraction of Bidens aurea on chronic gastric ulceration induced by 5% acetic acid in rats. The diethyl ether extract (125 and 62.5 mg kg-1 body weight) was administered in a single doses, 7 and 14 days after provocation of lesions. O ur results demonstrated that both doses significantly decreased the macro and microscopic ulcer index. Usually after 14-days treatment the lesions were found completely covered with regenerative epithelium and also an important proliferation of blood vessels was observed. Myeloperoxidase (M P O) activity was assayed and used as an index of leucocyte infiltration. Application of acetic acid pro­ duced a significant increase of this activity 7 days after induction of chronic injury. A d m in ­ istration of 125 mg kg 1 of the ether extract provoked a sharp reduction on the enzymatic activity at the same period. After 14 days, this decrease was higher with both doses (p<0.001). In addition, the macroscopic examination showed a drastic reduction of leucocyte infiltration in treated groups. These results suggest that the recovery of vascularization of the ulcerated area and the decrease of neutrophil infiltration are involved in the antiulcerogenic effect of the flavonoid fraction of Bidens aurea. 
  Reference    Z. Naturforsch. 51c, 570—577 (1996); received March 11/May 21 1996 
  Published    1996 
  Keywords    Bidens aurea, Flavonoids Chronic Gastric Ulcer, Neutrophils, Myeloperoxidase Activity 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0570.pdf 
 Identifier    ZNC-1996-51c-0570 
 Volume    51 
79Author    IouriE. Borissevitcha+, ChristianeP F Borgesa++, GalinaP. Borissevitcha+++, VictorE. Yushmanova+, SoniaR W Louroh, Marcel TabakaRequires cookie*
 Title    Binding and Location of Dipyridamole Derivatives in Micelles: the Role of Drug Molecular Structure and Charge  
 Abstract    Binding and localization of the vasodilator and antitumor drug coactivator dipyridamole (D IP) and of its three derivatives, RA14. RA47 and RA25 (D IP D), to cationic (cetyltrimeth-ylammonium chloride), anionic (sodium dodecylsulfate), zwitterionic (N-hexadecyl-N.N-di-methyl-3-ammonio-l-propanesulfonate). and neutral (r-octylphenoxypolyethoxyethanol) m i­ celles was studied using fluorescence, optical absorption and 'H N M R spectroscopy. The analysis of N M R . optical absorption and fluorescence data indicates that the depth of local­ ization of the drugs in the micelles from the surface decreased in the order D IP > RA 14 > RA47 > RA25. The binding constants for the neutral drug forms change in the same order in the range of 1400-3100 m _1 for D IP to 80-300 m _1 for RA25. This order is identical with the reported biological activity of D IP D . For the protonated drugs in zwitterionic or neutral micelles the binding constants are reduced by a factor of 20-75. 
  Reference    Z. Naturforsch. 51c, 578—590 (1996); received March 28/May 31 1996 
  Published    1996 
  Keywords    Dipyridamole and Derivatives, Micelle, Drug Location, Absorption, Fluorescence, N M R 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0578.pdf 
 Identifier    ZNC-1996-51c-0578 
 Volume    51 
80Author    M. Nogues, A. Cuenda, F. H. Enao, C. Gutierrez-M, ErinoRequires cookie*
 Title    Ca2+ Uptake Coupled to Glycogen Phosphorolysis in the Glycogenolytic-Sarcoplasmic Reticulum Complex from Rat Skeletal Muscle  
 Abstract    The glycogenolytic-sarcoplasmic reticulum complex from rat skeletal muscle accumulates C a2+ upon stimulation of glycogen phosphorolysis in the absence of added ATP. It is shown that an efficient C a2+ uptake involves the sequential action of glycogen phosphorylase, phos-phoglucomutase and hexokinase, which generate low concentrations of A TP (approximately 1 -2 ^m) compartm entalized in the immediate vicinity of the sarcoplasmic reticulum C a2+, Mg2+-ATPase (the C a2+ pump). The C a2+ uptake supported by glycogenolysis in this subcel-lular structure is strongly stimulated by micromolar concentrations of AMP, showing that the glycogen phosphorylase associated with this complex is in the dephosphorylated b form. The results point out that the flux through this compartmentalized metabolic pathway should be enhanced in physiological conditions leading to increased A M P concentrations in the sarcoplasm, such as long-lasting contractions and in ischemic muscle. 
  Reference    Z. Naturforsch. 51c, 591 (1996); received January 9/February 28 1996 
  Published    1996 
  Keywords    C a2 +-U ptake, Glycogenolysis, Sarcoplasmic Reticulum, Rat, Skeletal Muscle 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0591.pdf 
 Identifier    ZNC-1996-51c-0591 
 Volume    51 
Prev
1
2
3
4
5
...
Next