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2000[X]
101Author    A. Ntonio, F. M. Oliveira, Antonio SalatinoRequires cookie*
 Title    Major Constituents of the Foliar Epicuticular Waxes of Species from the Caatinga and Cerrado  
 Abstract    The epicuticular waxes of leaves of four species (Aspidospermci pyrifolium, Capparis yco, Maytenus rigida and Ziziphus joazeiro) from the Caatinga, (a semi-arid ecosystem of N orth­ east Brazil) and four species (Aristolochia esperanzae, Didymopanax vinosum , Strychnos pseudoquina and Tocoyena formosa) from the Cerrado, (a savanna ecosystem covering one third of the Brazilian territory), were analyzed. Six species contained a high content (above 60 (.ig.cm-2) of wax, four of them from the Caatinga. Triterpenoids and rc-alkanes were the most frequent and abundant constituents found in the species from both habitats. The distri­ bution of «-alkanes predom inated by homologues with 27, 29, 31 and 33 carbon atoms, dis­ played no consistent differences between species from the two habitats. Lupeol, ß-amyrin, epifriedelinol and ursolic acid were the triterpenoids found. Triterpenoids clearly predomi­ nate over alkanes in the waxes from the Cerrado species. The waxes of two evergreen species from the Caatinga yielded «-alkanes as predominant constituents. A comparison of foliar epicuticular waxes of native plants from ecosystems with different hydric constraints is dis­ cussed. 
  Reference    Z. Naturforsch. 55c, 688—692 (2000); received March 16/May 8. 2000 
  Published    2000 
  Keywords    Caatinga, Cerrado, Epicuticular Wax 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0688.pdf 
 Identifier    ZNC-2000-55c-0688 
 Volume    55 
102Author    Raquel Sánchez-M, Lucinda Artínez3, Manuel Villaescusa-Castillo3, Ana Bernabéb, Marí, D. Íaz-Lanza3Requires cookie*
 Title    Two New Eudesmane Alcohols from Jasonia glutinosa  
 Abstract    Asteraceae, Eudesmane Alcohols, Jasonia glutinosa Two new sesquiterpene alcohols have been isolated from the aerial parts of Jasonia glu­ tinosa D. C. The structure of these sesquiterpenes were characterized by ID and 2D NMR techniques (DQCOSY, TOCSY, NOESY, HM QC and HM BC) as (llfi)-eudesm -4-en-ll,12-diol and (ll/?)-eudesm ane-5a,ll,12-triol. 
  Reference    Z. Naturforsch. 55c, 693—696 (2000); received April 3/May 15 2000 
  Published    2000 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0693.pdf 
 Identifier    ZNC-2000-55c-0693 
 Volume    55 
103Author    M. Aría, A. González-Romero, Lucinda Villaescusa-Castillo, A. Na, M. D Íaz-LanzaRequires cookie*
 Title    Sesquiterpene Lactones from Inula montana L  
 Abstract    Asteraceae, Inula montana L., Sesquiterpene Lactones Aerial parts of Inula montana were investigated for its sesquiterpenoid composition. Five sesquiterpene lactones, isoinuviscolide, gaillardin, lß-hydroxy-3ß-acetoxy-eudesm-4(15), ll(13)-dien-12-8ß-olide, pulchellin-C and pulchellin-E were identified for the first time in this plant. One of them, lß-hydroxy-3ß-acetoxy-eudesm-4(15),ll(13)-dien-12-8ß-olide, is a novel natural product. The structures of this compounds were established by ID and 2D-NM R spectroscopy. 
  Reference    Z. Naturforsch. 55c, 697—700 (2000); received April 10/May 29 2000 
  Published    2000 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0697.pdf 
 Identifier    ZNC-2000-55c-0697 
 Volume    55 
104Author    Masayuki Sue, Atsushi Ishihara, Hajime IwamuraRequires cookie*
 Title    Occurrence and Characterization of a UDP-glucose:hydroxamic Acid Glucosyltransferase Isolated from Wheat (Triticum aestivum) Seedlings  
 Abstract    Cyclic Hydroxamic Acid. Glucosyltransferase, W heat (Triticum aestivum) Cyclic hydroxamic acid glucosides are present at high concentrations immediately after germination in wheat (Triticum aestivum L.). Changes in the activity of UDP-Glucose:cyclic hydroxamic acid glucosyltransferase (EC 2.4.1.-) in wheat were investigated using the cyclic hydroxamic acids 2,4-dihydroxy-l,4-benzoxazin-3-one (DIBO A) and its 7-methoxy derivative (DIM BOA) as sugar acceptors. Glucosyltransferase activity on both substrates was detected in dry seeds, with activity increasing after imbibition, peaking in shoots and roots 36-48 hours after imbibition and decreasing thereafter. The transience of glucosyltransferase activ­ ity was concurrent with the transient occurrence of the hydroxamic acid glucosides [Naka-gawa E., Amano T., Hirai N , and Iwamura H. (1995) Phytochemistry 38. 1349-1354], sug­ gesting that glucosyltransferases regulate the accumulation of hydroxamic acid glucosides in wheat seedlings. Two peaks in activity of UDP-Glucose:DIM BOA glucosyltransferase were detected using a Mono Q column, indicating the presence of at least two isozymes of this glucosyltransferase. The enzyme in the major peak was purified about 1500-fold and shown to be in a monomeric form with a molecular mass of 47 or 49 kDa. The enzyme reacted strongly with DIMBOA, less so with DIBOA. The enzyme of the minor peak on the Mono Q chromatogram, which was also a monomeric enzyme with a molecular mass of 47 kDa, showed similar substrate specificity to that of the major peak enzyme. 
  Reference    Z. Naturforsch. 55c, 701—707 (2000); received May 6 2000 
  Published    2000 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0701.pdf 
 Identifier    ZNC-2000-55c-0701 
 Volume    55 
105Author    Kolishka Tsekova3, Danka Galabovab, Kristina Todorova3Requires cookie*
 Title    Copper Accumulation and Phosphatase Activities of Aspergillus and Rhizopus  
 Abstract    Copper accumulation and phosphatase activities of three Aspergillus species resistant to copper were compared to three copper-sensitive Rhizopus species. High level of acid phos­ phatases and decreased Cu2+-uptake were found with resistant in contrast to sensitive strains. The presence of copper(II) ions in the medium increased the production of acid phosphatases in the resistant A. niger and decreased their activity in the sensitive R. delemar. Copper ions inhibited the activity of A. niger cellular acid phosphatase with a Kj of 8.9xl0"4 m and slightly activated the R. delemar enzyme. 
  Reference    Z. Naturforsch. 55c, 708—712 (2000); received February 8/June 13. 2000 
  Published    2000 
  Keywords    Aspergillus, Rhizopus, Copper Uptake, Phosphatase Activity 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0708.pdf 
 Identifier    ZNC-2000-55c-0708 
 Volume    55 
106Author    Afgan Farooq3, Satoshi TaharaabRequires cookie*
 Title    Biotransformation of Two Cytotoxic Terpenes, a-Santonin and Sclareol by Botrytis cinerea  
 Abstract    Two cytotoxic terpenes, a-santonin (1) and sclareol (3) were biotransformed by a plant pathogenic fungus Botrytis cinerea to produce oxidized metabolites in high yields. a-Santonin (1) on fermentation with the fungus for ten days afforded a hydroxylated metabolite iden­ tified as llß-hydroxy-a-santonin (2) in a high yield (83%), while sclareol (3) was metabolized to epoxysclareol (4) (64%) and a new compound 8-deoxy-14,15-dihydro-15-chloro-14-hy-droxy-8,9-dehydrosclareol (5) (7%), representing a rare example of microbial halogenation. 
  Reference    Z. Naturforsch. 55c, 713—717 (2000); received May 15/June 14 2000 
  Published    2000 
  Keywords    Biotransformation, a-Santonin, Sclareol, Botrytis cinerea 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0713.pdf 
 Identifier    ZNC-2000-55c-0713 
 Volume    55 
107Author    Karin Groten, Wolfgang BarzRequires cookie*
 Title    Elicitor-Induced Defence Reactions in Cell Suspension Cultures of Soybean Cultivars  
 Abstract    Suspension cultured soybean (Glycine max [L.] Merr.) cells of four cultivars (Wilis, Lumut, Kalmit, Doko RC) were compared for their response to different fungal and bacterial elici­ tors. Cells were treated either with crude cell wall extracts of the fungal pathogens Phytophth­ ora sojae (Pmg-elicitor) and Rhizoctonia solani (Riso-elicitor) or with two isolates of the bacterial pathogen Pseudomonas syringae pv. glycinea (Psg01/02) and a broad spectrum of antimicrobial defence reactions was measured. Cells of all four cultivars showed the same elicitor-induced rapid (H20 2 accumulation, alkalinization of the culture medium, peroxida-tive cross-linking of cell wall proteins) and slow (activation of phenylpropanoid metabolism, accumulation of phenolic compounds, induction of PR-proteins) defence responses. How­ ever, the reactivity of the cultivars was not identical in terms of time courses and intensities. Furthermore, the ability of the various elicitors to induce defence responses varied markedly. These differences indicate that (1) cells of the same species but of different cultivars are equipped with the same array of perception systems to recognise various stimuli but (2) the sensitivity of these perception systems or later steps in the signal transduction seem to be stimulated to a different extent in the analysed cultivars. 
  Reference    Z. Naturforsch. 55c, 718—730 (2000); received April 25/June 15 2000 
  Published    2000 
  Keywords    Oxidative Burst, PR-Proteins, Phenylpropanoid Metabolism 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0718.pdf 
 Identifier    ZNC-2000-55c-0718 
 Volume    55 
108Author    Katarzyna Woźniak, Zofia WalterRequires cookie*
 Title    Induction of DNA-Protein Cross-Links by Platinum Compounds  
 Abstract    The differences between cis-and mws-diamminedichloroplatinum II (DDP) in forming DNA-protein cross-links in isolated human lymphocytes were investigated. Both cis-and rra/75-DDP can induce DNA-protein cross-links. We show that cis-DDP forms complexes between D N A and proteins faster than trans-DDP. This results from an increase in the quan­ tity of D NA and platinum together with an increase in drug concentration. Under the same conditions trans-DDP causes a decrease in DNA-forming complexes with proteins. After a 12 h incubation of lymphocytes we observe a similar level of DNA in DNA-protein cross­ links induced by D D P isomers, but more platinum appears in complexes induced by trans-DDP. The results obtained demonstrate that the antitumor drug -ds-DDP and the clinically ineffective trans-DDP induce links between D N A and proteins in a different manner. We suggest that the therapeutic activity of ds-DDP can in part arise from rapidly forming DNA-protein complexes which can destroy the most important cellular processes, such as replica­ tion and transcription. 
  Reference    Z. Naturforsch. 55c, 731—736 (2000); received March 30/June 26 2000 
  Published    2000 
  Keywords    Lymphocytes, DNA-Protein, Cross-Links 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0731.pdf 
 Identifier    ZNC-2000-55c-0731 
 Volume    55 
109Author    Joachim Rauchs, Dietmar Wolf, Michael Hausmann#, Christoph CremerRequires cookie*
 Title    The Influence of Formamide on Thermal Denaturation Profiles of DNA and Metaphase Chromosomes in Suspension  
 Abstract    Thermal Denaturation, Formamide Treatment, Hyperchromicity Systematic photometric studies are presented to analyze the thermal denaturation behavi­ our with and without formamide of metaphase chromosome suspensions in comparison to D N A solutions. Temperature dependent hyperchromicity measurements at 256 nm and 313 nm were performed using an appropriately designed computer-controlled photometer device. Due to an upright optical axis, this allowed absorbance measurements with negligible sedimentation effects not only for solutions of pure DNA, but also for particle suspensions of isolated metaphase chromosomes. This device has a temperature resolution of ± 0.5 °C and an optical sensitivity of 10~3 to 10-4 optical density. For calf thymus D N A the reduction of the melting point with the increase of formamide in the solution was measured at pH 7.0 and pH 3.2. The good correlation of the theoretical approximation to experimental data indicated the suitability of the apparatus to quantitatively describe D N A conformation changes induced by thermal denaturation. For metaphase chromosome preparations of Chi­ nese hamster culture cells, absorbance changes were measured between 20 °C and 95 °C with a temperature gradient of 1 °C/min. These measurements were performed at pH 7.0 and at pH 3.2. The denaturation profiles (= first derivative of the absorbance curve) resulted in a highly variable peak pattern at 256 nm and 313 nm indicating complex conformation changes. A statistical evaluation of the temperature values of the peak maxima resulted in temper­ ature ranges typical for chromosomal conformation changes during thermal treatment. Espe­ cially the range of highest temperature values was independent from pH modifications. For pH 3.2 the influence of formamide on the denaturation behaviour of metaphase chromosome preparations was analyzed. In contrast to pure DNA solutions, a reduction of the "melting point" (i.e. the maximum temperature at which a conformation change takes place) was not found. However, the denaturation behaviour depended on the duration of formamide treat­ ment before the measurement. 
  Reference    Z. Naturforsch. 55c, 737—746 (2000); received March 12/May 22 2000 
  Published    2000 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0737.pdf 
 Identifier    ZNC-2000-55c-0737 
 Volume    55 
110Author    Dieter Müller-Enoch3, Hans GrulerbRequires cookie*
 Title    Complexation of Membrane-Bound Enzyme Systems  
 Abstract    The effect of changes in the N-terminal membrane-binding domain of cytochrome P450 forms and NADPH-cytochrome P450 reductase types on the cytochrome P450-dependent monooxygenase activities, has been examined. The nifedipine oxidase activity of two human P450 forms (CYP3A4, CYP3A4NF14) which differ only in their primary structure by ten amino acid residues in the N-terminal membrane-binding domain, yields nearly the same catalytic cycle time x =2.65 ± 0.15 s, due to their identical cytosolic catalytic protein structure. In contrast, the complex formation process ([P450]+[reductase] [complex]) described by the dissociation constant K D at high substrate concentration ([5]»/C5) and low product con­ centration ([ P ] « /^) is determined to be /CD/[P450]o = 0.3 and 2.0, respectively. These values reflect large differences in the affinity of both P450 forms for the same type of reductase which is only due to their modified membrane-binding domains. In the present work, it has been shown for the first time, that the membrane-binding domain of cytochrome P450 en­ zymes determines the complexation process of the binary P450:reductase system. Further­ more, the nifedipine oxidase activity of the human CYP3A4 form reconstituted with two different types of reductase from human and rabbit also has the same catalytic cycle time x = 2.65 ± 0.15 s. This result is based on the similarity of the primary structure of the cytosolic catalytic domain of both reductase types. However, the complex was formed with different dissociation constants of A T D/[P450]o = 0.3 and 4.7, respectively. This different affinity of both reductase types to the same P450 form is interpreted as a consequence of the substantial alteration of the amino acids in the N-terminal primary structure of their membrane-binding domains. 7-Ethoxycoumarin O-deethylase activity of two rat P450 forms (CYP2B1 and CYP1A1) were reconstituted with the same rat reductase. The catalytic cycle time for each P450 form is x = 1.8 and 0.6 s, respectively. Correspondingly, the complex formation process controlled by the dissociation constant K n has changed from /CD/[P450]o = 2.3 to 1.7, respec­ tively. This is because both forms differ in their cytosolic as well as in their membrane-binding domains. 
  Reference    Z. Naturforsch. 55c, 747—752 (2000); received April 13/May 20 2000 
  Published    2000 
  Keywords    Cytochrome P450, NADPH-Cytochrome P450 Reductase, Membrane-Binding Domains 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0747.pdf 
 Identifier    ZNC-2000-55c-0747 
 Volume    55 
111Author    BożennaR. Óżycka-Roszak, Hanna PruchnikRequires cookie*
 Title    Influence of Dodecyltrimethylammonium Halides on Thermotropic Phase Behaviour of Phosphatidylcholine/Cholesterol Bilayers  
 Abstract    Effects of dodecyltrimethylammonium chloride (DTAC), dodecyltrimethylammonium bro­ mide (DTAB) and dodecyltrimethylammonium iodide (DTAI) on thermotropic phase behav­ iour of phosphatidylcholine bilayers containing cholesterol as well as on 'H N M R spectra were studied. Two series of experiments were performed. In the first one the surfactants were added to the water phase while in the other directly to the lipid phase (a mixed film from cholesterol, surfactant and phosphatidylcholine was formed). The effects of particular surfactants on the main phase transition temperature, Tm, were more pronounced when added to the lipid phase (2 nd method) than to the water phase (1 st method); the opposite happened when cholesterol was absent (Rözycka-Roszak and Pruchnik 2000, Z. Naturforsch. 55c, 240-244). Furthermore, in the case of the first method the transitions were asymmetrical while in the second method nearly symmetrical. It is suggested that surfactant poor and surfactant rich domains are formed when surfactants are added to the water phase. 
  Reference    Z. Naturforsch. 55c, 753—757 (2000); received March 27/May 11 2000 
  Published    2000 
  Keywords    Counterions, Phosphatidylcholine Bilayers, Cholesterol 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0753.pdf 
 Identifier    ZNC-2000-55c-0753 
 Volume    55 
112Author    Janina Gabrielska3, Teresa Kral3, Marek Langnerb, Stanislaw Przestalski3Requires cookie*
 Title    Different Effects of Di-and Triphenyltin Compounds on Lipid Bilayer Dithionite Permeabilization  
 Abstract    Phenyltins, Lipid Bilayer, Membrane Permeability Phenyltins are chemicals widely used in industry, hence their occurrence in the human environment is frequent and widespread. Such compounds include hydrophobic phenyl rings bonded to positively charged tin. Tliis molecular structure makes them capable of adsorbing onto and penetrating through biological membranes, hence they are potentially hazardous. Two such compounds, diphenyltin and triphenyltin, show different steric constraints when interacting with the lipid bilayer. It has been demonstrated that these compounds are posi­ tioned at different locations within model lipid bilayers, causing dissimilarity in their ability to affect membrane properties. In this paper we present a study regarding the ability of these two phenyltins to facilitate the transport of S20 4-2 ions across the lipid bilayer, evaluated by a fluorescence quenching assay. In concentration range of up-to 60 [.i m those compounds do not affect lipid bilayer topology, when evaluated by vesicle size distribution. Both phenyltins facilitate the transfer of S20 4-2 across the model lipid bilayer, but the dependence of dithio­ nite transport on phenyltin concentration is different for both. In principle, above 20 triphenyltin is more efficient in transfering ions across the lipid bilayer than diphenyltin. 
  Reference    Z. Naturforsch. 55c, 758—763 (2000); received May 9/June 8 2000 
  Published    2000 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0758.pdf 
 Identifier    ZNC-2000-55c-0758 
 Volume    55 
113Author    Halina Kleszczyriska3, Krzysztof Bieleckib, Janusz Sarapuka, Anna Dziamska3, Stanislaw Przestalski3Requires cookie*
 Title    Influence of Triphenyllead Chloride on Biological and Model Membranes  
 Abstract    Triphenyllead Chloride. Toxicity. Lipid Membrane Destabilization The physiological and hemolytic toxicities of triphenyllead chloride (TPhL) as well as its modyfying influence on model lipid membranes were studied. The experiments allowed the determination of TPhL concentrations causing 50% inhibition of growth of Spirodela oligorr-hiza, Lemna minor and Solvinia natans (EC50), 100% hemolysis of pig erythrocytes (C 10o) and destabilization of planar lipid membranes (CC). Also, fluidity of erythrocyte ghosts was measured by fluorescence technique and osmotic sensitivity of erythrocytes to the presence of TPhL. All parameters studied were found to be dependent on pH, of experimental solu­ tions and the concentration of TPhL. Acidic conditions increased EC50, C i0o and CC concen­ trations of TPhL. Fluorescence and osmotic measurements showed that osmotic stability and fluidity decreased with increasing trimethyllead concentration. A possible mechanism of TPhL toxicity is discussed. It is assumed that TPhL is interacting with the lipid phase of the models used. It is also assumed that there may exist various, ionic and nonionic, forms of TPhL as a result of its speciation under different experimental conditions. These species, due to their differentiated lipophilicity, may exert different effects on the model membranes studied. 
  Reference    Z. Naturforsch. 55c, 764—769 (2000); received May 16/June 21 2000 
  Published    2000 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0764.pdf 
 Identifier    ZNC-2000-55c-0764 
 Volume    55 
114Author    HetalG. Patel3, RadhaV. Aras3, KunjanR. Daveb, SurendraS. Katyare3Requires cookie*
 Title    Kinetic Attributes of Na+ , K+ ATPase and Lipid / Phospholipid Profiles of Rat and Human Erythrocyte Membrane  
 Abstract    Erythrocyte Membrane, Na+ , K + ATPase, Temperature and Substrate Kinetics Kinetic properties of Na+ , K + ATPase of membranes from rat and human erythrocytes were examined. The enzyme stability decreased with incubation time. The Vmax of the human enzyme was about 4 times lower than the values of the rat enzyme. However the energies of activation were higher. Phase transition temperature for the rat and the human enzyme was 24 °C and 17 °C, respectively. The human erythrocyte membranes were characterized by lower total phospholipid and cholesterol contents and were relatively more fluid. The human membranes contained lower proportions of acidic phospholipids which correlated well with the lower Vmax of the enzyme; the proportion of lysophosphoglyceride and sphingomyelin was higher in the human membrane. 
  Reference    Z. Naturforsch. 55c, 770—777 (2000); received May 8/June 21 2000 
  Published    2000 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0770.pdf 
 Identifier    ZNC-2000-55c-0770 
 Volume    55 
115Author    Josep Serra Bonvehí, FrancescVentura CollRequires cookie*
 Title    Study on Propolis Quality from China and Uruguay  
 Abstract    The composition, bacteriostatic and R O O »-scavenging potential activities of fifteen propo­ lis samples from various botanic and geographic origins were determined to obtain objective information related to propolis quality. Variance analysis showed significant differences (p < 0.05) in the contents of polyphenols, flavonoids and active components between fresh and aged propolis. The state of the product (fresh or aged) could be differentiate by using flavo-noid pattern and biological activities. A minimum propolis concentration of 80 [.ig/ml was required inhibit Bacillus subtilis and Staphylococcus aureus while 800 |J.g/ml was required to inhibit Escherichia coli using fresh propolis. Aged propolis inhibit B. subtilis and S. aureus at concentration of 100 [ig/ml and E. coli at 1000 [j.g/ml. A minimum flavonoids percentage of 18 g/100 g and a maximum R O O • -scavenging potential activity of 4.3 |^g/ml were determined in fresh propolis. Flavonoids levels in aged propolis were approximately 20% lower than in fresh propolis. A maximum flavonoids percentage of 19.8 g/100 g and a ROO*-scavenging potential activity between 5.7 to 6.4 [ig/ml in aged propolis were quantified. Another objec­ tive was to assess the use of ROO*-scavenging potential activity in propolis quality. 
  Reference    Z. Naturforsch. 55c, 778—784 (2000); received March 20/May 8 2000 
  Published    2000 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0778.pdf 
 Identifier    ZNC-2000-55c-0778 
 Volume    55 
116Author    Milena Velikova3, Vassya Bankova3, MariaC. Marcuccib, Iva Tsvetkova0, Atanas KujumgievcRequires cookie*
 Title    Chemical Composition and Biological Activity of Propolis from Brazilian Meliponinae  
 Abstract    Propolis, Meliponinae, Antimicrobial Activity Twenty-one propolis samples produced by 12 different Meliponinae species were analyzed by GC-MS. Several chemical types of stingless bees' propolis could be grouped, according to the prevailing type of compounds like: "gallic acid", "diterpenic" and "triterpenic" types. The results confirm that neither the bee species nor the geographical location determine the chemical composition of Meliponinae propolis and the choice of its plant source, respectively. This could be explained by the fact that Meliponinae forage over short distances (maximum 500 m) and thus use as propolis source the first plant exudate they encounter during their flights. The antibacterial, antifungal and cytotoxic activities of the samples were also investi­ gated. Most samples had weak or no activity against E. coli, weak action against Candida albicans. Some of them showed significant activity against St. aureus., presumably connected to the high concentration of diterpenic acids. Samples rich in diterpenic acids possessed also high cytotoxic activity (Artemia salina test). 
  Reference    Z. Naturforsch. 55c, 785—789 (2000); received May 2/June 23 2000 
  Published    2000 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0785.pdf 
 Identifier    ZNC-2000-55c-0785 
 Volume    55 
117Author    Milena Velikova3, Vassya Bankova, Kadriye Sorkunb, Saadi Houcinec, Iva Tsvetkovad, A. KujumgievdRequires cookie*
 Title    Propolis from the Mediterranean Region: Chemical Composition and Antimicrobial Activity  
 Abstract    The chemical composition of propolis from Bulgaria, Turkey, Greece and Algeria was investigated by GC-MS. All of them contained mainly flavonoids and esters of caffeic and ferulic acids, which indicated that their main source are buds of poplars of the taxonomic section Aegieros. Some Turkish samples contained a low percent of diterpenic acids, while in Algerian samples significant amounts of a hydroxyditerpenic acid (M=322, its structure not determined by its MS) were found. All samples showed significant antibacterial and weak to moderate antifungal activity. 
  Reference    Z. Naturforsch. 55c, 790—793 (2000); received May 10/June 19 2000 
  Published    2000 
  Keywords    Propolis, Populus, Antimicrobial Activity 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0790.pdf 
 Identifier    ZNC-2000-55c-0790 
 Volume    55 
118Author    Krasimir Slantchev3, Kamen Stefanov3, Katya Seizova3, Simeon Popov3, Stoitse AndreevbRequires cookie*
 Title    Botryllus schlossen  
 Abstract    Botryllus schlossen, Phospholipids, Sterols Eighteen sterols were identified in Botryllus schlossen, stanols being the main sterols. The sterol composition is in agreement with our recent paper on taxonomic separation of tuni-cates into three groups. Again we found in invertebrates of the Black Sea sterols with a (22Z)-double bond. This confirms the presence of such sterols in nature. The composition of the phospholipids appeared to be complex, and twelve groups of them were identified in Botryllus schlossen. The main representatives of phospholipids appeared to be phosphati­ dylcholine and phosphatidylethanolamine. Only four volatile compounds were identified, which is unusual for marine invertebrates. 
  Reference    Z. Naturforsch. 55c, 794—798 (2000); received March 14/May 11 2000 
  Published    2000 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0794.pdf 
 Identifier    ZNC-2000-55c-0794 
 Volume    55 
119Author    PetiaA. Dimitrova3, RenetaA. Toshkovab, EmiliaH. Ivanova3, ZvetankaH. Stefanova3, MariaB. Angelova3, PavlinaA. Dolashkac, W. VoelterdRequires cookie*
 Title    Superoxide Production by Phagocytes in Myeloid Graffi Tumor-Bearing Hamsters  
 Abstract    A progressive suppression of the phagocytic ability of peritoneal macrophages and poly-morphonuclears (PMNs) in hamsters with transplanted myeloid tumors was previously estab­ lished. The i.p. application of Cu/Zn SOD, isolated from the fungal strain Humicola lutea (H LSO D) (2 injections before and 5 injections after tumor transplantation) induced the mean survival time of the animals as well as a temporally stimulating action on the macro­ phage and PMNs phagocyting indices. In the present work, the superoxide production of peritoneal macrophages and PMNs during 30 days of tumor progression was followed. Effects of the application of H LSO D in an optimal protective dose on the superoxide production in peritoneal macrophages and blood PMNs were examined. The spontaneous and phorbol-myristate acetate (PMA)-inducible 0 2~ production in both types of phagocytes was 4-5-fold increased in tumor-bearing hamsters (TBH), as compared to the controls, at day 14 after tumor transplantation (the day of tumor appearance in transplanted animals). Furthermore, 0 2~ production was also similar to the control values for the following days of observation. H LSO D treatment of TBH induced a normalization of superoxide production in macro­ phages and PMNs. Therefore, the established decrease of superoxide anions in phagocyting cells of TBH indicates possible effects of HLSOD on the host antioxidant defense. 
  Reference    Z. Naturforsch. 55c, 799—805 (2000); received April 19/May 19 2000 
  Published    2000 
  Keywords    Superoxide Dismutase, Macrophages, Tumors 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0799.pdf 
 Identifier    ZNC-2000-55c-0799 
 Volume    55 
120Author    Anne-Mari Mustonen, Petteri Nieminen, Heikki Hyvärinen, Juha AsikainenRequires cookie*
 Title    Exogenous Melatonin Elevates the Plasma Leptin and Thyroxine Concentrations of the Mink (M us tela vison)  
 Abstract    Eight male and eight female minks were given exogenous melatonin as subcutaneous im­ plants. The plasma leptin and thyroxine concentrations were measured. The leptin concentra­ tions showed clear seasonal variations and differences between the experimental groups. In September most of the control females had undetectable plasma leptin concentrations, but the melatonin-treated females had detectable concentrations significantly higher than the leptin levels of the controls. Most of the males had undetectable leptin concentrations, too. In October the plasma leptin levels had increased significantly in all the groups except the control males. The melatonin-treated minks had significantly higher leptin levels than the controls. There was a significant rise in the thyroxine levels from September to October and the melatonin-treated groups had significantly higher thyroxine levels than the controls. The effects of exogenous melatonin are very pronounced in the mink. Melatonin elevates the plasma leptin and thyroxine levels possibly by direct and indirect mechanisms. 
  Reference    Z. Naturforsch. 55c, 806—813 (2000); received April 18/May 12. 2000 
  Published    2000 
  Keywords    Melatonin, Leptin, Mustela vison 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0806.pdf 
 Identifier    ZNC-2000-55c-0806 
 Volume    55 
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