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1993 (158)
1Author    H. Ans, W. Rauwald, Anette BeilRequires cookie*
 Title    5-Hydroxyaloin A in the Genus Aloe Thin Layer Chromatographic Screening and High Performance Liquid Chromatographic Determination  
 Abstract    Aloe, Asphodelaceae, 5-Hydroxyaloin A, Quinones, Chemotaxonomy By a comparative thin layer chrom atographic screening o f the methanol-soluble leaf exu­ dates from more than 400 Aloe plants (183 species), 5-hydroxyaloin A was identified in 20 species. Whilst 13 of the 20 species revealed interindividual variations concerning to the oc­ currence of 5-hydroxyaloin A, this anthrone-C-glucosyl was unam biguously detected in each individual of 6 Aloe species. In the leaf exudates from A. marlothii Berger 5-hydroxyaloin A was only traceable in the aloin-containing chemivars. The complete anthrone-C-glucosyl p at­ tern of these 7 clearly characterized species has been determined additionally by qualitative and quantitative high performance liquid chrom atography: The results obtained dem onstrate th at 5-hydroxyaloin only occurs in the more stable A -configuration (10 R, 1 'S), thus being till now the only anthrone-C-glycosyl which has not been found as diastereomeric pair genuinely in plants. As well, 5-hydroxyaloin A characterizes a quantitatively significant hydroxylating pathway in biosynthesis of anthranoids. It is discussed as a chemotaxonomic m arker of the genus Aloe, especially of the sections Pachydendron and Eualoe. 
  Reference    Z. Naturforsch. 48c, 1—4 (1993); received December 12 1992 
  Published    1993 
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 TEI-XML for    default:Reihe_C/48/ZNC-1993-48c-0001.pdf 
 Identifier    ZNC-1993-48c-0001 
 Volume    48 
2Author    M. Uham, M. Ad, Nazir, W. Aqar, Ahm Ad, NaeemA. Khtar, Rabi, Shafiq Ahm, K. HanRequires cookie*
 Title    Epicuticular Leaf Wax of Euphorbia helioscopia L. (Euphorbiaceae)  
 Abstract    The epicuticular wax of Euphorbia helioscopia was fractionated into fatty acids, hydrocar­ bons, wax esters, aldehydes, methyl esters, triterpenol acetates, alcohols, sterols, and polar components. The com position o f the fractions was determined by GC, GC-MS, HPLC. Main com ponents within these lipid classes are hentriacontane, wax esters C ^ and C4g, octacosanal, hexacosanol and octacosanol, hexadecanoic acid, and ß-sitosterol. Lupeol and its acetate were also confirmed. 
  Reference    Z. Naturforsch. 48c, 5 (1993); received September 23 1992 
  Published    1993 
  Keywords    helioscopia, Epicuticular Wax Composition, Fatty Acids, Hydrocarbons, Wax Esters 
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 TEI-XML for    default:Reihe_C/48/ZNC-1993-48c-0005.pdf 
 Identifier    ZNC-1993-48c-0005 
 Volume    48 
3Author    SabineG. Ubatz, R. Olf WiermannRequires cookie*
 Title    Studies on Sporopollenin Biosynthesis in Cucurbita maxima I: The Substantial Labeling of Sporopollenin from Cucurbita maxima after Application of [14C]Phenylalanine  
 Abstract    The results of tracer experiments performed with anthers of Tulipa cv. Apeldoorn have already shown that a high level of incorporation into the sporopollenin fraction was achieved, when [14C]phenylalanine was applicated as a precursor. In order to investigate whether the substantial incorporation of [14C]phenylalanine is a unique phenom enon restricted to Tulipa, tracer experiments were carried out on anthers of Cucurbita maxima. The sporopollenin fraction was isolated and purified by a gentle method including extrac­ tions with various solvents, incubations with hydrolysing enzymes and fractionated saponifi-cations. The remaining, as well as the released radioactivity, was determined after each purifi­ cation step. After the application of [U-14C]phenylalanine, a substantial incorporation into the sporopollenin fraction was determined. The values were clearly higher than those obtained with [ l-l4C]glucose or those from corresponding experiments on Tulipa anthers. After potash fusion o f sporopollenin fractions labeled via [U-14C]phenylalanine, /»-hydroxybenzoic acid was shown to be the main com ponent am ong the ether soluble acids; moreover it showed the highest level of radioactivity. N o radioactivity was detected in the degradation products oxalic acid, benzoic acid, phthal-ic acid and terephthalic acid or octanedioic acid-and decanedioic acid-dimethylester. 
  Reference    Z. Naturforsch. 48c, 10—15 (1993); received October 19 1992 
  Published    1993 
  Keywords    Cucurbitaceae, Cucurbita maxima, Tracer Experiments, Potash Fusion, Sporopollenin 
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 TEI-XML for    default:Reihe_C/48/ZNC-1993-48c-0010.pdf 
 Identifier    ZNC-1993-48c-0010 
 Volume    48 
4Author    Satoshi Tahara, Fum Ihiko Saitoh, Junya MizutaniRequires cookie*
 Title    7-O-Methyl-luteone Metabolism in Botrytis cinerea: Identification of the Epoxy-Intermediate and Absolute Configuration of the Pyrano-isoflavone Metabolite  
 Abstract    Fungal Metabolism, Botrytis cinerea, 7-O-methyl-luteone, Prenylisoflavone, Epoxy-Inter-mediate. Stereochemistry 7-O-Methyl-luteone was metabolized in a buffer solution by resting cells of Botrytis cinerea which is known as a fungus detoxifying prenylated isoflavones into further oxygenated m eta­ bolites, and we could isolate an unstable epoxy-intermediate. The epoxy-intermediate was easily cyclized under acidic conditions to yield the corresponding isoflavone with a hydroxy-chrom an part structure (= dihydropyrano-isoflavone). The optically active (dextrorotatory) dihydropyrano-isoflavone metabolite was derivatized into the [/?]-a-methoxy-a-trifluoro-methyl-phenylacetic acid ester and its absolute configuration [5] was unambiguously eluci­ dated by the modified M osher's method. 
  Reference    Z. Naturforsch. 48c, 16 (1993); received November 13 1992 
  Published    1993 
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 Identifier    ZNC-1993-48c-0016 
 Volume    48 
5Author    N. G. Rotjohann, G. Schneider, W. KowallikRequires cookie*
 Title    Different Forms of Fructose 1,6-Bisphosphatase in Chlorella  
 Abstract    In crude extracts of Chlorella kessleri two forms of fructosebisphosphatase can be separated by ion exchange chrom atography or by acid precipitation. FBPase I is eluted from DEAE cel­ lulose at 200 m M KC1 and precipitated at pH 4.5, FBPase II is correspondingly eluted at 310 m M KC1 and soluble at pH 4.5. Both enzymes differ in substrate affinity and degree of cooperativity. Based on literature data, FBPase I is assumed to be of cytosolic and FBPase II of chloroplastic origin. The mole mass of FBPase I is identical (51-65 kDa) at pH 6.5 and pH 8.5. T hat of FBPase II is however, about four times larger at pH 6.5 (257 kDa) than at pH 8.5 (67 kDa). Other pH values have only been tried with crude cell extracts in which still larger mole masses of FBPase resulted at more acidic pH (1349 kD a at pH 6.0). The lower mole mass form of FBPase II shows three times higher catalytic activity. Reducing agents, such as DTT, also increase the activity of FBPase II in vitro. In vivo, alkalization and production o f reducing power occurs in the chloroplast stroma du­ ring illumination. If the above alterations exist in vivo, they would be a means to activate FBPase in the light. Oligomerization of FBPase II to aggregates with altered catalytic activities and kinetic prop­ erties is discussed as result of the action of specific wavelengths and to be responsible for differ­ ences in carbohydrate metabolism of Chlorella exposed to red or blue light. 
  Reference    Z. Naturforsch. 48c, 22 (1993); received October 12/November 25 1992 
  Published    1993 
  Keywords    Chlorella kessleri, Fructosebisphosphatase, Superose-FPLC, DEAE-Chrom atography, Enzyme Oligomerization 
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 TEI-XML for    default:Reihe_C/48/ZNC-1993-48c-0022.pdf 
 Identifier    ZNC-1993-48c-0022 
 Volume    48 
6Author    M. Artin, W. Estermann, Wolfgang Reuter, Christine Schimek, W. Erner WehrmeyerRequires cookie*
 Title    Presence of Both Hemidiscoidal and Hemiellipsoidal Phycobilisomes in a Phormidium Species (Cyanobacteria)  
 Abstract    Cyanobacteria, Phycobilisomes, U ltrastructure, Chrom atic A daptation, Phormidium sp. C 8 6 Hemidiscoidal and hemiellipsoidal phycobilisomes have been determined in cells o f the complementary chromatically adapting cyanobacterium Phormidium sp. C 8 6 . They could be isolated from red and green light-adapted cells, respectively. Hemidiscoidal red light phyco­ bilisomes show molar pigment ratios o f allophycocyanin: phycocyanin of 1:4.5 with phyco-erythrin lacking. Hemiellipsoidal phycobilisomes induced by green light present allophyco­ cyanin: phycocyanin: phycoerythrin ratios of 1 :1 : 6 .8 . The differences between the two phy-cobilisome types could additionally be dem onstrated by their ultrastructure and sedimentation values. Isolated red light phycobilisomes have six rods, show dimensions of 70 x 30 x 15 nm and a sedimentation value o f 6 6 S whereas green light phycobilisomes are nearly twice larger. They contain ten rods and present dimensions o f 70 x 40 x 25 nm and a sedimentation value of 98 S. The number of phycobilisomes in red light cells is almost twice as large as in green light cells. There is evidence that cells grown under white light contain both types as well as "inter­ mediate" forms. 
  Reference    Z. Naturforsch. 48c, 28—3 (1993); received October 8 /December 14 1992 
  Published    1993 
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 Identifier    ZNC-1993-48c-0028 
 Volume    48 
7Author    Andreas Jacobi3, R. Olf Zettlb, Klaus Palmeb, DietrichW. Erner3Requires cookie*
 Title    An Auxin Binding Protein is Localized in the Symbiosome Membrane of Soybean Nodules  
 Abstract    Auxin Binding Protein, Symbiosome Membrane, Phytotropins Binding of tritiated indole-3-acetic acid ([3H]IAA) to symbiosome membranes o f soybean nodules occurred in a protein-dependent m anner and was competitively inhibited by unlabeled indole-3-acetic acid (IAA), 1-naphthaleneacetic acid (1-NAA) and dithiothreitol (DTT), but not by tryptophan and benzoic acid. The symbiosome membranes bound IAA with a ATD of 1 x 10~6 m. Photoaffinity labeling identified an auxin-binding protein (ABP) in the symbio­ some membrane with an apparent molecular mass of 23 kD a. This 23 kD a protein was labeled either with 5-azido-[7-3H]indole-3-acetic acid ([3H ]N3IAA) or with 5'-azido-[3,6-3H J-1-naphthylphthalamic acid ([3H JN 3N PA). Labeling o f the 23 kDa protein with [3H ]N3IAA was competitively inhibited by unlabeled IAA and 1-NAA. NPA and quercetin, inhibitors of polar auxin transport, as well as rutin, a glycosylated derivative of quercetin, competed with IAA for binding. Conversely, [3H 2]N 3N PA labeling was inhibited by unlabeled IAA and NPA. The 23 kD a symbiosome membrane protein was partially solubilized with Triton X-100 and nearly completely using Triton X-114. The observation that auxin transport inhibitors com ­ pete with IAA for binding suggests that the symbiosome membrane ABP could be part o f an auxin efflux carrier system required to control the auxin concentration in infected soybean nodule cells. 
  Reference    Z. Naturforsch. 48c, 35—40 (1993); received December 3 1992 
  Published    1993 
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 Identifier    ZNC-1993-48c-0035 
 Volume    48 
8Author    Thom As Urbig, Rüdiger Schulz, H. Orst SengerRequires cookie*
 Title    Inactivation and Reactivation of the Hydrogenases of the Green Algae Scenedesmus obliquus and Chlamydomonas reinhardtii  
 Abstract    The hydrogenases of the green algae Scenedesmus obliquus and Chlamydomonas reinhardtii were activated under anaerobic conditions. Exposure o f whole cells and cell-free homogenates to air lead to a complete inactivation of the hydrogenases. The inactivation in whole cells of Scenedesmus is faster than the inactivation of the cell-free homogenate. Inactivation o f the hy­ drogenases could be reversed by anaerobic readaptation in whole cells. The inactivation of the hydrogenase in homogenates seems to be irreversible. N either the removal o f oxygen nor the addition of ATP, N AD(P)H, sodium dithionite, dithiothreitol, ferredoxin and thioredoxin to homogenates facilitated the reactivation o f the hydrogenase. The occurrence of a hydrogenase regulating factor is discussed. 
  Reference    Z. Naturforsch. 48c, 41 (1993); received September 30/December 21 1992 
  Published    1993 
  Keywords    Scenedesmus obliquus, Chlamydomonas reinhardtii, Hydrogenase, Reactivation Process, Inactivation 
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 TEI-XML for    default:Reihe_C/48/ZNC-1993-48c-0041.pdf 
 Identifier    ZNC-1993-48c-0041 
 Volume    48 
9Author    WieslawI. Gruszecki, ZbigniewK. RupaRequires cookie*
 Title    Changes of Excitation Spectra of in vivo Chlorophyll Fluorescence during Induction of Photosynthesis  
 Abstract    Excitation spectra of chlorophyll fluorescence from intact rye leaves were registered at dif­ ferent steps of the induction of photosynthesis after dark adaptation. Analysis of these spectra indicates that at least two processes related to spectroscopic features are responsible for a flu­ orescence quenching. The first one, active during the first 100 s of illumination, was interpret­ ed to consists in an overall decrease of the fluorescence quantum yield of antenna pigments and chlorophylls, in particular close to the reaction centers. The second type of a fluorescence decrease (between 100 s and 300 s o f illumination) was found to be in large extent related to decrease of the rate of an excitation energy transfer between accessory xanthophyll pigments and chlorophylls emitting fluorescence. This latter molecular mechanism is discussed as being related to violaxanthin availability to de-epoxidation in the xanthophyll cycle. 
  Reference    Z. Naturforsch. 48c, 46—51 (1993); received September 21/December 31 1992 
  Published    1993 
  Keywords    Chlorophyll Fluorescence, Photosynthesis, Violaxanthin, Xanthophyll Cycle 
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 TEI-XML for    default:Reihe_C/48/ZNC-1993-48c-0046.pdf 
 Identifier    ZNC-1993-48c-0046 
 Volume    48 
10Author    Hans-Adolf Arfmann, W. A. Olf-Rainer, G. Braham, BfRequires cookie*
 Title    Microbial Reduction of Aromatic Carboxylic Acids  
 Abstract    Several benzoic, cinnamic and phenylacetic acid derivatives were screened with 20 micro­ organisms, mainly fungi, for the reduction o f their carboxylic function. For all organisms sev­ eral compounds were reduced in fairly good yields up to 80% to the corresponding alcohol. N o general rule could be established, concerning the substitution pattern, as to which com ­ pounds were transformed to the alcohol. Generally the reactions were accomplished within 4 8 -7 0 h. Only minor, if any, side products were detected. Dicarboxylic acids, such as phthalic or phenylglutaric acids and similar com pounds could not be reduced by the microorganisms tested. 
  Reference    Z. Naturforsch. 48c, 52 (1993); received October 19/November 11 1992 
  Published    1993 
  Keywords    Aromatic Carboxylic Acids, M icrobial Transformation, Reduction, A lcohol Formation 
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 Identifier    ZNC-1993-48c-0052 
 Volume    48 
11Author    G. Udrun Preibisch, Christina Kiiffner, ErichF. ElstnerRequires cookie*
 Title    Biochemical Model Reactions on the Prooxidative Activity of Homocysteine  
 Abstract    Hom ocysteine, Oxygen A ctivation, Atherogenesis The sulfur amino acid hom ocysteine has recently been addressed as marker for vessel dam­ aging and atherosclerotic dispositions. The atherogenic index has been correlated with the one o f cholesterol and is significantly higher in cholesterinemic as compared to normal lipidemic persons. In the present com m unication biochemical model reactions are presented indicating the prooxidative activity o f hom ocysteine where a cooperative effect with the transition-metals copper and iron is indicated. 
  Reference    Z. Naturforsch. 48c, 58 (1993); received December 1 1992 
  Published    1993 
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 Identifier    ZNC-1993-48c-0058 
 Volume    48 
12Author    M. Ałgorzata, M. M. Roczkowska, JarosławT K UśmierekRequires cookie*
 Title    The Effect of Neighboring Bases on Miscoding Properties of N2,3-Ethenoguanine  
 Abstract    The m iscoding potential o f N 2,3-ethenoguanine (G G), one o f the carcinogen vinyl chloride adducts to D N A bases, has been examined by copying o f poly (A, £ G) templates with D N A -dependent R N A polymerase and reverse transcriptase. In contrast to the results previously ob­ tained with poly (C, 6 G) templates where 6 G acts as G and A, in poly (A, 6 G) templates E G acts alm ost exclusively as A. These results suggest that mutagenic potential o f E G in vivo can depend on the nature o f neighboring bases. 
  Reference    Z. Naturforsch. 48c, 63—6 (1993); received June 26/Decem ber 
  Published    1993 
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 Identifier    ZNC-1993-48c-0063 
 Volume    48 
13Author    F. A. Tom Ás-Barberán, F. Ferreres, F. Tom Ás-Lorente, A. OrtizRequires cookie*
 Title    Flavonoids from Apis mellifera Beeswax  
 Abstract    The flavonoids present in beeswax produced in "La Alcarria" region were analyzed by HPLC. Pinocembrin, pinobanksin, pinobanksin 3-acetate, chrysin, galangin and techtochry-sin were detected as the main flavonoid constituents. This is the first detailed report on the flavonoids o f beeswax. These substances are already present when wax scales are secreted by bees. The same flavonoid com pounds were generally present in honey, propolis and Populus nigra bud exudates collected in the same geographical region. These results indicate that bees­ wax flavonoids originate from those o f honey and/or propolis, and suggest that analysis o f beeswax flavonoids could be used as an adjunct in the detection o f beeswax adulterations. 
  Reference    Z. Naturforsch. 48c, 68—7 (1993); received N ovem ber 19 1992/January 1 1993 
  Published    1993 
  Keywords    Beeswax, Apis mellifera, Flavonoids, H oney, Propolis, Botanical Origin, Characterization 
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 TEI-XML for    default:Reihe_C/48/ZNC-1993-48c-0068.pdf 
 Identifier    ZNC-1993-48c-0068 
 Volume    48 
14Author    J. R. Aldrich, H. N. Um Ata, E. N., F. Bin, G.K W Aite, W. R. LusbyRequires cookie*
 Title    Artifacts and Pheromone Blends from Nezara spp. and Other Stink Bugs (Heteroptera: Pentatomidae)  
 Abstract    Isomeric com pounds reportedly released by mature males o f N ezara viridula as attractants for conspecific females are evidently artifacts formed by dimerization o f (£)-4-oxo-2-hexenal. Additional analyses o f the male-specific volatiles from Italian, Australian, Brazilian, and Jap­ anese populations o f N. viridula verify that at least two distinctive pheromone strains exist, but an active synthetic pheromone has not yet been developed. Analyses o f volatiles from N. an-tennata and Acrosternum aseadum males are also reported showing that the native Japanese Nezara sp., and species in the sister genus Acrosternum, produce species-specific blends based on the same com pounds as N. viridula: (Z)-a-bisabolene (l-m eth yl-4-(l,5-d im eth yl-(Z)-l,4-hexadienyl)-cyclohexene), and trans-and cis-1,2-epoxides o f (Z)-a-bisabolene. The trans-/cis-I,2-epoxide ratio o f N. antennata is within the range found for m ost N. viridula populations, but the blend from Japanese N. viridula males deviates radically from those o f other conspe­ cific populations. 
  Reference    Z. Naturforsch. 48c, 73—7 (1993); received July 21 1992 
  Published    1993 
  Keywords    Hemiptera, Euschistus, Podisus, Attractant, Bisabolene 
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 Identifier    ZNC-1993-48c-0073 
 Volume    48 
15Author    Jürgen Jacob, Britt Ziemsen, Udo HoppeRequires cookie*
 Title    Cast Skin Lipids of the Indian Python (Python molurus bivittatus, Kühl, 1820)  
 Abstract    Cast skins o f various snakes and in addition one lizard were found to contain 3 .5 -8 .6 % extractable lipid material. Lipids obtained from a cast skin o f the Indian python were analyzed in detail indicating the presence o f hydrocarbons (squalene, cholestadiene and alkanes), monoester waxes, sterol esters, diester waxes, triglycerides, sterols, free fatty acids and even more polar lipids. A m ong the monoester wax constituents odd-numbered secondary alkanols were found. It is assumed that the above lipids originate from cells o f the past integumental generation and that they play an important facilitating role during the sloughing process. 
  Reference    Z. Naturforsch. 48c, 80—8 (1993); received September 28 1992 
  Published    1993 
  Keywords    Skin Lipids, Cast Skin, Snakes, Sterols, Secondary Alcohols 
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 Identifier    ZNC-1993-48c-0080 
 Volume    48 
16Author    H. SchimassekRequires cookie*
 Title    Glycogen Synthesis in Rat Liver from a Pool of Free Glucose  
 Abstract    Glycogen synthesis in isolated perfused livers or livers o f anesthetized rats (in situ), was studied using radioactively labelled fructose, lactate, and inositol as substrates. The specific radioactivity o f glucose and glycogen was measured at various times and compared with that o f some intermediates. The results suggest that liver glycogen is formed from the pool o f free glucose which in turn is fed by the so-called "direct and indirect pathway" o f glycogen synthesis. This points to an important role o f glucose-6-phosphatase, an enzyme complex subject to regulation by gluco­ corticoids, well known promoters o f hepatic glycogen synthesis. 
  Reference    Z. Naturforsch. 48c, 85—9 (1993); received September 14 1992 
  Published    1993 
  Keywords    Rat Liver, Glycogen Synthesis, Fructose, G lucocorticoids, Glucose-6-phosphatase 
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 Identifier    ZNC-1993-48c-0085 
 Volume    48 
17Author    Helmut Reuß, Hennig StieveRequires cookie*
 Title    Two Different Bump Types of the Ventral Photoreceptor of Limulus  
 Abstract    The elementary responses, the "bumps", o f the ventral photoreceptor o f Limulus polyphe-mus were measured under voltage clamp conditions. We observed a type o f bump which differs in size and time parameters from the "standard" bumps described previously. The average value o f the amplitude o f these "small, slow " bumps is about 20-fold smaller than that o f the standard bumps (about 1 nA) and the average latency is about 25% longer. The duration o f these bumps is 2 -5 -fo ld longer than that o f a standard bump with the same amplitude. The small, slow bumps are probably light-induced and arise with about the same frequency after a light flash as standard bumps. The different kinetics o f the two bump types can be explained by the assumption that the transduction chain branches into at least two pathways. 
  Reference    Z. Naturforsch. 48c, 92 (1993); received December 17 1992 
  Published    1993 
  Keywords    Limulus Ventral Nerve Photoreceptor, Light-Induced Bumps, Spontaneous Bumps, Small Slow Bumps 
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 Identifier    ZNC-1993-48c-0092 
 Volume    48 
18Author    Nikolaus TrojeRequires cookie*
 Title    Spectral Categories in the Learning Behaviour of Blowflies  
 Abstract    Wavelength discrimination in the flower visiting blowfly Lucilia spec, was investigated in an attempt to elucidate the mechanisms underlying colour vision in this insect. The flies were sub­ jected to a classical conditioning procedure in which they had to discriminate between a re­ warded and an unrewarded monochrom atic light stimulus. The results reveal large wavelength ranges within which no discrimination occurs, between which, however, a very distinct dis­ crimination is found. The first range consists o f the UV region up to 400 nm (U V). The second range comprises wavelengths between 400 nm and 515 nm (B L U E) and the third range all wavelengths longer than 515 nm (YELLOW). A simple model consisting o f two colour oppo­ nent subsystems (R 7 p /R 8 p and R 7 y /R 8 y) can explain these results. Each o f the two subsys­ tems is assumed to evaluate only whether the sign o f the difference between the excitations o f R 7 and R 8 is positive or negative. For the whole system there are thus four possible condi­ tions: p +y +, p +y", p~y+, p "y~. Three o f them correspond to the experim entally obtained wave­ length ranges. The fourth condition (p+y~) might represent a still hypothetical PU R PLE cate­ gory in which the stimulus is made up o f both short and long wavelengths. 
  Reference    Z. Naturforsch. 48c, 96—104 (1993); received January 7 1993 
  Published    1993 
  Keywords    Blowfly, W avelength Discrimination, Colour Categories, Learning, Photoreceptors 
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 TEI-XML for    default:Reihe_C/48/ZNC-1993-48c-0096.pdf 
 Identifier    ZNC-1993-48c-0096 
 Volume    48 
19Author    Heilmittel Helixor, C. O. GmbhRequires cookie*
 Title    Viscum album L. ssp. abietis, album und austriacum New Investigations on Flavonoids from Viscum album L. ssp. abietis, album and austriacum Elmar Lorch  
 Abstract    Viscum album, M istletoe, HPLC, Flavonoids, Sakuranetin Hydrolyzed alcoholic extracts o f Viscum album L. were analyzed by HPLC for their flavonoid content. Be­ sides the known flavonoid aglyca 4',5,7-trihydroxy-3'-methoxyflavanone (hom oeriodictyol), 5,7-dimethoxy-4'-hydroxyflavanone, 3'-methylquercetin (isorhamnetin) and 3',7-dimethylquercetin (rhamnazin) another flava-none derivate, 4',5-dihydroxy-7-m ethoxyflavanone (sakuranetin) was detected in mistletoe extracts for the first time. With the described method it is possible to dis­ tinguish the three mistletoe subspecies abietis, album and austriacum. 
  Reference    Z. Naturforsch. 48c, 105—107 (1993); received December 14 1992 
  Published    1993 
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 Identifier    ZNC-1993-48c-0105_n 
 Volume    48 
20Author    Shimizu, Yoshiko Tatsuki, N. Aokuni TakedaRequires cookie*
 Title    Toshiaki  
 Abstract    The venom gland o f the braconid parasitoid, Apan­ teles kariyai, was m orphologically observed with photo­ m icroscope and aromatic amino acids in its venom fluid were chemically analyzed with a three-dimension­ al HPLC svstem-coulometric ECD. Tyrosine (TYR-4) —> tyramine (T Y R A) — * ■ hydroxyphenylacetic acid (H PA C -4) and tryptophan (TRP) — * kynurenine (K Y N) were the detected metabolic pathways. This re­ port o f venom components o f a braconid wasp outlines qualitative differences between this and venom from so­ cial wasps. 
  Reference    Z. Naturforsch. 48c, 108—109 (1993); received October 30 1992 
  Published    1993 
  Keywords    Aromatic Am ino Acids, Venom, Braconid Parasitoid, Apanteles kariyai 
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 Identifier    ZNC-1993-48c-0108_n 
 Volume    48 
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