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1994[X]
81Author    Ursula Beate Hacker-KlomRequires cookie*
 Title    Diurnal Changes in Murine Spermatogenesis  
 Abstract    We analysed testicular samples of NMRI mice every 2 h of a day in order to determine whether there is a circadian rhythm in spermatogenetic activity. We used flow cytometry after staining the D N A with DAPI. The highest proportion of D N A synthesizing cells (mainly spermatogonia and preleptotene spermatocytes) was seen at 8 p.m. and especially at 1 0 p.m.; the lowest proportion was observed at 2 p.m. At 6 a.m., the percentage of round spermatids increased significantly, whereas the fraction of 4c-cells decreased at that time. Our results of a diurnal rhythm of spermatogenic D N A synthesis rate are in contrast to another publication of other authors (Oakberg and Crosswait, 1983). 
  Reference    Z. Naturforsch. 49c, 522 (1994); received February 28/April 19 1994 
  Published    1994 
  Keywords    Mouse Spermatogenesis, Photoperiod Dependency Flow Cytometry S-Phase Cells, Physical and Chemical Noxae 
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 TEI-XML for    default:Reihe_C/49/ZNC-1994-49c-0522.pdf 
 Identifier    ZNC-1994-49c-0522 
 Volume    49 
82Author    Alka Agarwal3, ShivK. Agarwal3, SomNath Singhb, Nigar Fatmab, R.K C HatterjeebRequires cookie*
 Title    Structure-Antifilarial Activity Relationship of 5/6/7/8-Mono-or Disubstituted lH/l-Phenyl-9H-pyrido[3,4-b]indoles -A New Class of Potential Filaricides  
 Abstract    Antifilarial Activity, ß-Carbolines, Substituted 9H-Pyrido[3,4-b]indoles Antifilarial activity of 5/6/7/8-mono-or disubstituted 1 H /l-phenyl-9H -pyrido[3,4-b]indoles (I) has been described. The 1,6-and 8 -substituted 9H-pyrido[3,4-b]indoles (I) elicited inter­ esting filaricidal activity against L itom osoides carinii and Acanthocheilonem a viteae in rodent hosts. 
  Reference    Z. Naturforsch. 49c, 526 (1994); received D ecem ber 30 1993/April 20 1994 
  Published    1994 
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 Identifier    ZNC-1994-49c-0526 
 Volume    49 
83Author    JensD. SchwennRequires cookie*
 Title    Photosynthetic Sulphate Reduction Comparative Biochemistry, Photosynthetic Sulphate Reduction, Cysteine Biosynthesis, Structural G ene(s), Enzyme Mechanism, ATP Sulphurylase/APS Kinase Cysteine Biosynthesis: Two Pathways for One Product?  
  Reference    Z. Naturforsch. 49c, 531 (1994); received March 24/May 20 1994 
  Published    1994 
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 TEI-XML for    default:Reihe_C/49/ZNC-1994-49c-0531.pdf 
 Identifier    ZNC-1994-49c-0531 
 Volume    49 
84Author    St Blech, H. Budzikiewicz, D. DillRequires cookie*
 Title    /?-Carboline Alkaloids from R ibes nigrum L  
 Abstract    From Ribes nigrum L. two ß-carboline alkaloids (deshydroxymethyl flazin (1) and flazin methyl ether (2)) could be isolated in minute amounts. The structure elucidation is described. The two compounds are present in the freshly pressed juice, but they are also formed during storage of the juice by condensation of tryptophane with ascorbic acid or its degradation products. This could be shown by adding 14C-labelled ascorbic acid to the juice. A fter four weeks' incubation radioactive 1 and 2 could be isolated. 
  Reference    Z. Naturforsch. 49c, 540 (1994); received May 20 1994 
  Published    1994 
  Keywords    Ribes nigrum L, ß-Carboline Alkaloids, Flazin Derivatives, Biogenesis 
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 TEI-XML for    default:Reihe_C/49/ZNC-1994-49c-0540.pdf 
 Identifier    ZNC-1994-49c-0540 
 Volume    49 
85Author    Dagmar Busmann, RalfG. Ünter BergerRequires cookie*
 Title    Oxyfunctionalization o f a-and ß-Pinene by Selected Basidiomycetes  
 Abstract    Several strains of basidiom ycetes were examined for their ability to transform a-and ß-pinene in agitated submerged cultures. Four major metabolites of a-pinene (verbenol, ver-benone, myrtenol, and rrorcs-pinocarveol) and three main metabolites of ß-pinene (1,4-cineol, myrtenol, and rrarcs-pinocarveol) were isolated from the fermentation broth. The metabolic pathways included allylic oxidation, oxidative cleavage and further regioselective oxidation. G anoderm a applanatum was found to carry out the stereoselective allylic hydroxylation of a-pinene to verbenol, and o f ß-pinene to trans-pinocarveol in trans position to the C -C bridge. The optimal conditions of the bioreaction were established with respect to substrate concentration, incubation time and conversion time. D ue to growth inhibition caused by elevated substrate concentration, the bioconversion of ß-pinene required pre-grown cultures. Generally, mycelial pellet cultures were supplemented with the terpene substrate when a residual glucose content of 50% was reached. Depending on strain this point was reached after about 48 h. A n incubation period of two to three days gave best yields. The transient accumulation of oxygenated products apparently reflected different reaction velocities of the successive catabolic steps. 
  Reference    Z. Naturforsch. 49c, 545 (1994); received May 26/June 20 1994 
  Published    1994 
  Keywords    Pinene, Cineol, Basidiomycetes, Bioconversion, Transformation 
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 TEI-XML for    default:Reihe_C/49/ZNC-1994-49c-0545.pdf 
 Identifier    ZNC-1994-49c-0545 
 Volume    49 
86Author    Gbf-Gesellschaft Für, Biotechnologische Forschung, MbhAbteilung Mikrobiologie, M. Ascheroder WegRequires cookie*
 Title    W olf-R ainer A b rah am  
 Abstract    D edicated to Professor Fritz Wagner on the occasion o f his 65th birthday Biotransform ation, Phylogeny, Isopinocampheol, Enantioselectivity, Microbial Hydroxylation Biotransform ation of isopinocampheol with 100 bacterial and fungal strains yielded 1-, 2-, 4-, 5-, 7-, 8 -and 9-hydroxy-isopinocampheol besides three rearranged monoterpenes, one of them bearing the novel isocarane skeleton. A pronounced enantioselectivity between (+)-and (-)-isopinocam pheol was observed. The phylogenetic position of the individual strains could be seen in their ability to form the products from (+)-isopinocampheol. The formation of 1,3-dihydroxypinane is a domain of bacteria, while 3,5-or 3,7-dihydroxypinane was mainly formed by fungi, especially those of the phylum Zygomycotina. The activity of Basidiomycotina towards oxidation of isopinocampheol was rather low. Such informations can be used in a more effective selection of strains for screening. 
  Reference    Z. Naturforsch. 49c, 553—560 (1994); received March 11 1994 
  Published    1994 
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 Identifier    ZNC-1994-49c-0553 
 Volume    49 
87Author    G. Erh, RdE. Rk El, TimmA. NkeRequires cookie*
 Title    Hyphodontal, a New Antifungal Inhibitor of Reverse Transcriptases from Hyphodontia sp. (Corticiaceae, Basidiomycetes)  
 Abstract    R o b e rt V elten, A lb erto G im enez and W olfgang Steglich In a search for inhibitors of RNA-directed DNA polymerases a new isolactarane sesquiter-penoid, hyphodontal (1), was isolated from fermentations of a Canadian Hyphodontia species. Its structure was elucidated by spectroscopic methods. Hyphodontal strongly inhibits the growth of several yeasts and is a non-competitive inhibitor of avian myeloblastosis virus (Kj 346 ^ m) and Moloney murine leukemia virus (K 112 (i m) reverse transcriptases. In addition, cytotoxic and antifungal activities were observed. 
  Reference    Z. Naturforsch. 49c, 561—570 (1994); received May 5/ 
  Published    1994 
  Keywords    Hyphodontia sp, Basidiomycetes, Sesquiterpenes, Isolactaranes, Reverse Transcriptases 
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 TEI-XML for    default:Reihe_C/49/ZNC-1994-49c-0561.pdf 
 Identifier    ZNC-1994-49c-0561 
 Volume    49 
88Author    J. Sivý, V. K. Ettm Ann, J. K. Rätsm Ár-Šm, Ogrovič, M. B. RezaRequires cookie*
 Title    On the Mechanism of Metabolic Reactions of Amino Acids Catalyzed by Vitamin B6 and Related Aldehydes  
 Abstract    [(N-salicylidene-D,L-glutamato)(pyridine)]copper(II), Crystal Structure, INDO/2 Charges, Metabolic Reactions of Amino Acids, Vitamin B6 Catalysis, Reaction Mechanism The crystal structure of [(N-salicylidene-D,L-glutamato)(pyridine)]copper(II), a model for vitamin B6-amino acid-related metal complexes, has been determ ined by an X-ray analysis. A close examination of the structural data on this and other related complexes combined with quantum-chemical (INDO/2) calculations enabled us to make a clear distinction be­ tween two mechanisms proposed earlier for metabolic reactions of amino acids catalyzed by the vitamin BA (or salicylaldehyde)-metal system. The results are consistent with a transient formation of a carbinolamine species resulting from the addition of a solvent water or alcohol molecule to the Schiff base double bond, thus supporting the mechanism of the catalysis as proposed by Gillard and Wootton. In tro d u ctio n 
  Reference    Z. Naturforsch. 49c, 571—578 (1994); received April 25 1994 
  Published    1994 
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 Identifier    ZNC-1994-49c-0571 
 Volume    49 
89Author    Requires cookie*
 Title    Light-Harvesting Complexes of Aerobic Bacteriochlorophyll-Containing Bacteria Roseococcus thiosulfatophilus, RB3 and Erythromicrobium ramosum, E5 and the Transfer of Excitation Energy from Carotenoids to Bacteriochlorophyll  
  Reference    Z. Naturforsch. 49c, 579 (1994) 
  Published    1994 
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 TEI-XML for    default:Reihe_C/49/ZNC-1994-49c-0579.pdf 
 Identifier    ZNC-1994-49c-0579 
 Volume    49 
90Author    S.I A Llak H V Erd Iev, '. Bc, M. S. Karacan, G. S. Om Erb, N. K. Aracanb, H. An, S.Y R An Ec, S. Padhyec, V.V K Lim Ov3, G. R. EngerdRequires cookie*
 Title    Binuclear Manganese(III) Complexes as Electron Donors in Dl/D2/Cytochrome b 559 Preparations Isolated from Spinach Photosystem II Membrane Fragments  
 Abstract    The capability of different manganese complexes to act as PS II electron donors in D 1/D 2/ cytochrome b 559 complexes has been analyzed by measuring actinic light-induced absorption changes at 680 nm (650 nm) and 340 nm, reflecting the photoaccumulation of Pheophytin' (Pheo-) and the reduction of NADP+, respectively. The data obtained reveal: a) the donor capacity of synthetic binuclear Mn(III)2 complexes containing aromatic ligands significantly exceeds that for MnCl2 in both cases, i.e. Pheo-photoaccumulation and NADP+ reduction; b) manganese complexes can serve as suitable electron donors for light-induced NADP+ reduction catalyzed by D 1/D 2/cytochrome £>559 complexes and ferredoxin plus ferredoxin-NADP+ reductase under anaerobic conditions and c) the specific turnover rate of the system leading to NADP+ reduction is extremely small. The implications of these findings are briefly discussed. In tro d u ctio n The essential steps of photosynthetic w ater cleavage tak e place w ithin an integral m em brane com plex associated with extrinsic regulatory poly­ peptides. This o p eratio n al unit is referred to as photosystem II (PS II) complex. The prim ary reac­ tions of PS II com prise light absorption, excitation energy tran sfer to th e photoactive pigm ent (a spe­ cial chlorophyll a designated as P680) and elec­ tron tran sfer from its excited singlet state to p heo­ phytin a (P heo) acting as prim ary acceptor and subsequen t stabilization of the prim ary charge sep aration by rap id electron transfer from P h eo -to a special plasto q u in o n e m olecule Q A (R enger, 1992). B ased on sim ilarities of the functional and structural organization of the prim ary processes, com ponents P680, P heo and Q A w ere inferred to 
  Reference    Z. Naturforsch. 49c, 587—592 (1994); received June 24/ 
  Published    1994 
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 Identifier    ZNC-1994-49c-0587 
 Volume    49 
91Author    F. L. Figueroa, J. A. Guilera, F. X. NiellRequires cookie*
 Title    End-of-Day Light Control of Growth and Pigmentation in the Red Alga Porphyra umbilicalis (L.) Kiitzing  
 Abstract    Absorptance, Cell Area, Chlorophyll a, End-of-Day Light, Intracellular C and N The effects of end-of-day light pulses on thallus expansion, cell size, pigmentation and intracellular accumulation of C and N in the red alga Porphyra umbilicalis were analysed. Red (R) light pulses applied at the end of 12 h white light photoperiod for 14 d stimulated thallus expansion and produced an increase in cell size. Growth rate was higher after red (R) than after blue (B) light pulses. Red or blue light affect thallus expansion, but not the thallus weight, and was partially reversed by far-red (FR) light pulses. Red light pulses promoted chlorophyll a accumulation whereas B light pulses stimulated the accumulation of phycoerythrin, phycocyanin and soluble protein. The effects of R or B light pulses on pigmentation were partially reversed by FR light, except for phycocyanin. Intracellular C content was similar under both R and B light treatments and higher than after FR light pulses and non-irradiated control. However, intracellular N content was higher after end-of-day R than after end-of-day B light pulses. Total absorptance (400-760 nm) of the thalli was higher after B than R light pulses. However, the ratio of total absorptance and concentration of total pigments (chlorophyll and biliproteins), used as index of light absorp­ tion efficiency, was higher after R than after end-of-day B light pulses. The efficiency of light absorption decreased after the application of FR light pulses. These observations explain the higher growth rate, in terms of thallus expansion, after R than after B end-of-day light pulses and FR treatments. The possible action of phytochrome and a B light photoreceptor in the control of growth and pigmentation in Porphyra umbilicalis is suggested. 
  Reference    Z. Naturforsch. 49c, 593—600 (1994); received April 11 1994 
  Published    1994 
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 Identifier    ZNC-1994-49c-0593 
 Volume    49 
92Author    IngoM. Aier, D. Ieter, G. M. ÜllerRequires cookie*
 Title    Spermatozoid Chemotaxis in Laminaria digitata (Phaeophyceae). III. Pheromone Receptor Specificity and Threshold Concentrations  
  Reference    Z. Naturforsch. 49c, 601 (1994) 
  Published    1994 
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 Identifier    ZNC-1994-49c-0601 
 Volume    49 
93Author    Z. NaturforschRequires cookie*
 Title    Impact of UV-B Radiation on the Lipid and Fatty Acid Composition of Synchronized Ditylum brightwellii (West) Grunow  
 Abstract    Lipid and Fatty Acid Composition, UV-B Effects, Synchron Cultures, Marine Diatoms The marine diatom Ditylum brightwellii (West) Grunow isolated from the Baltic Sea could be synchronized by a light/dark rhythm of 6.5:17.5 h (white light intensity 8 W m 2) at 18 °C and 0.035 vol.% C 0 2. Content of protein, DNA and RNA increased linearly up to the end of the cell cycle. Pigments (chlorophyll a, chlorophyll C\ +c2, carotenoids) and galactolipids were synthesized in the light period only. A lag phase of 2 h was observed in the biosynthesis of sulphoquinovosyl diacylglycerol and phosphatidylglycerol. Formation of phosphatidyl­ glycerol and phosphatidylcholin continued in the dark period (30% and 28%, respectively). The pattern of major fatty acids (C14:0, C16:1, C16:o, C18:1 and C2():5) varied during the cell cycle of Ditylum. Biosynthesis of acyl lipids was reduced in dependence on the UV-B dose. The most sensi­ tive lipid was digalactosyl diacylglycerol (total inhibition at 585 J m -2), whereas phosphatidyl­ cholin was less affected (20% reduction). UV-B radiation during the dark period had no effect on the lipid and pigment content. Strongest inhibitory effect of UV-B on cell division, synthesis of protein, pigments, sulphoquinovosyl diacylglycerol and phosphatidylglycerol was found after UV-B radiation at the beginning of the cell cycle (0.-2. h). An exposure time at the end of the light period (4.-6. h) led to a marked damage on the synthesis of monogalacto-syl diacylglycerol and phosphatidylglycerol. These findings indicate a stage-dependent re­ sponse of Ditylum to UV-B irradiance. The impact of UV-B resulted in an increase of unsatu­ rated long chained fatty acids (C)8, C20) and in a diminution of short chained fatty acids (C14, C)6). Content of ATP was not affected by UV-B radiation under the used conditions. The inhibitory effect of UV-B on synthesis of DNA, RNA, protein and acyl lipids was mainly reversible. Results were discussed with reference to UV-B damage on the enzymes involved in the biosynthesis of acyl lipids and by a reduction of available metabolites. 
  Reference    Z. Naturforsch. 49c, 607—614 (1994); received April 25/ 
  Published    1994 
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 Identifier    ZNC-1994-49c-0607 
 Volume    49 
94Author    J. Benavente, A. M. Uñoz, A. HerediaRequires cookie*
 Title    Ionic Permeabilities of Different Isolated Fruit Cuticles Calculated by Conductivity and Membrane Potential Measurements  
 Abstract    Membrane potential and electrical resistance for two isolated fruit cuticular membranes (tomato and pepper cuticles) were measured for different NaCl solutions (10-3 m < C < 5 x l 0 ~ 2 m). From these experimental results some membrane characteristic parameters were obtained such as cation transport number, t+, which represents the fraction of the electric current transported by the cation, / + , with respect to the total current, / x (t+ = / + / / t) , and ionic permeabilities. P + and P_, for both membranes. Concentration dependence of these parameters was also considered. A comparative study between both types of fruit cuticles is also made. It was found that cation transport number, ionic permeabilities and electrical resistances are quite similar for both membranes. 
  Reference    Z. Naturforsch. 49c, 615—618 (1994); received May 9/June 8 1994 
  Published    1994 
  Keywords    Fruit Cuticles, Membrane Potential, Membrane Conductivity, Ionic Permeabilities 
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 TEI-XML for    default:Reihe_C/49/ZNC-1994-49c-0615.pdf 
 Identifier    ZNC-1994-49c-0615 
 Volume    49 
95Author    ChristineM. Richter, Aloysius WildRequires cookie*
 Title    Phenolic Compounds in Needles of Norway Spruce Trees in Relation to Novel Forest Decline. II. Studies on Trees from Two Sites in Middle Western Germany  
 Abstract    The content of several phenolic compounds in needles of 20-to 30-year-old Norway spruce trees (Picea abies) was measured using HPLC. The results of two forestry sites in middle western Germany are reported in this paper. They are part of a research programme on novel forest decline which was carried out in various regions of Germany. Distinct amounts of picein, catechin, piceatannol glucoside, and other phenolic compounds were detected in the studied spruce needles. Additionally, their contents changed in relation to damage. Some compounds, especially catechin, showed increased levels in the needles of the damaged trees compared to the undamaged ones. Here, the values for the undamaged trees of the different sites were similar. Concerning the changes in picein contents, however, there was a great difference between the sites. p-Hydroxyacetophenone was detected in very low amounts only and did not correlate with damage. These results are compared with earlier findings from another site that shows severe dam­ age. The role of phenolic compounds as indicators of tree damage is discussed. 
  Reference    Z. Naturforsch. 49c, 619—627 (1994); received January 31/June 16 1994 
  Published    1994 
  Keywords    Phenolic Compounds, Picea abies, Novel Forest Decline, Picein, Catechin 
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 Identifier    ZNC-1994-49c-0619 
 Volume    49 
96Author    Tetsuo Kokubun, JeffreyB. Harborne, Phytoalexins Constitutive Fungitoxins, Hydroquinone AucuparinRequires cookie*
 Title    A Survey of Phytoalexin Induction in Leaves of the Rosaceae by Copper Ions  
 Abstract    The leaves of 130 species of Rosaceae were surveyed for phytoalexin induction. Both biotic and abiotic induction was examined and antifungal compounds were detected in 47 species. However, these compounds appeared to be constitutive metabolites, released from bound phenolic materials already present in the leaf. In Pyrus, hydroquinone was produced from the hydrolysis of arbutin present in the vacuole before inoculation. In most other species, the fungitoxic agents were mainly catechin-like derivatives, apparently released from the tannins present within the leaf. By contrast, the synthesis in the leaf of the characteristic biphenyl or benzofuran phytoalexins which are produced in sapwood, was confined to a very few species. The biphenyl aucuparin was identified as a phytoalexin from the leaves of Sorbus aucuparia. 
  Reference    Z. Naturforsch. 49c, 628—634 (1994); received April 28/May 26 1994 
  Published    1994 
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 Identifier    ZNC-1994-49c-0628 
 Volume    49 
97Author    M. Artina Kaufmann, Michael WinkRequires cookie*
 Title    Molecular Systematics of the Nepetoideae (Family Labiatae): Phylogenetic Implications from rbcL Gene Sequences  
 Abstract    Total DNA was extracted from 41 species (20 genera) of the subfamily Nepetoideae (fam­ ily Labiatae). Using rbcL-specific primers, the rbcL gene was amplified by polymerase chain reaction (PCR) and sequenced directly. RbcL sequences were evaluated with character state (maximum parsimony; PAUP) and distance methods (neighbour-joining; MEGA). In agree­ ment with classical systematics all taxa studied cluster within the Nepetoideae and are clearly distinguished from members of the subfamily Lamioideae. A number of distinctive clades are apparent within the Nepetoideae:, and XIII -Perovskia. At least five main branches rep­ resenting the clades I, II, III to VII, VIII, and IX to XIII respectively, can be distinguished within the Nepetoideae studied. They might be considered representing the tribes (according to Cantino, 1992) Elsholtzieae (I), Lavanduleae (II), and Mentheae (III — XIII). The tribe Mentheae needs to be subdivided into at least three main groups (clades III-V II, VIII and IX -X II I). Major ana hortensis which is often classified as Origanum hortensis does not cluster with Origanum and deserves a generic status of its own. 
  Reference    Z. Naturforsch. 49c, 635—645 (1994); received April 18/May 31 1994 
  Published    1994 
  Keywords    rbcL, Phylogeny, Labiatae, Nepetoideae, Nucleotide Sequences I -Collinsonia, II -Lavandula, III -Agastache, Glechoma, IV -Satureja, Hyssopus, Dracocephalum, V -Nepeta, VI -Hormium, VII -Prunella, VIII -Melissa, Ocimum, IX -Monarda, Mentha, X -Origanum, Thymus, XI -Salvia, XII -Rosmarinus 
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 Identifier    ZNC-1994-49c-0635 
 Volume    49 
98Author    Ulrich SchreiberRequires cookie*
 Title    New Emitter-Detector-Cuvette Assembly for Measuring Modulated Chlorophyll Fluorescence of Highly Diluted Suspensions in Conjunction with the Standard PAM Fluorometer  
 Abstract    A new emitter-detector-cuvette assembly for the standard PAM fluorometer is described which leads to substantial improvement of signal/noise ratio and increased flexibility with respect to the choice of excitation and emission wavelengths. These features are particularly useful for work with very dilute suspensions of unicellular algae and isolated chloroplasts. Instead of fiber optics perspex rods are applied for guiding excitation light to a mirrored 10x10x45 mm cuvette and from there at 90° angle to the photodetector, similarly as recently reported for a PAM fluorometer based on Xe-flash measuring light (Schreiber et al. (1993), Photosynth. Res. 36, 65-72). While the detection limit of the new system does not reach that of the Xe-PAM fluorometer, it is approximately two orders of magnitude higher than that of the standard system. Rapid induction kinetics can be measured at low chlorophyll concen­ trations down to 0.1 (.ig-ml '. Satisfactory quenching analysis for detection of active chloro­ phyll concentration is still possible at 5 |ig chlorophyllT '. The various optical factors con­ tributing to the improved sensitivity are analyzed. An accessory device is described by which the frequency of the measuring light pulses generated by the PAM fluorometer is lowered in order to reduce the actinic effect of the measuring light. The performance of the new system using different excitation and emission wavelengths is demonstrated in measurements with green algae, cyanobacteria and leaves. Applying a newly available blue light-emitting diode with 450 nm peak emission, short wavelength fluorescence enriched in PS II emission can be measured, which is characterized by high values of variable fluorescence relative to maximal fluorescence. Using measuring light covering five different wavelength ranges the fluorescence contributions from cyanobacteria and green algae can be distinguished on the basis of distinct differences in their excitation spectra. This approach should become useful for an estimation of content and activity of different types of phytoplankton in natural surface waters. 
  Reference    Z. Naturforsch. 49c, 646—656 (1994); received May 18/July 7 1994 
  Published    1994 
  Keywords    Chlorophyll Fluorescence, Photosynthesis, PAM Fluorometer, Quenching Analysis, Unicellular Algae, Cyanobacteria, Phytoplankton 
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 Identifier    ZNC-1994-49c-0646 
 Volume    49 
99Author    J. Schole, Chr Schole, J. EikemeyerRequires cookie*
 Title    Diethyl Phosphate Binding to Mitochondrial Cardiolipin after Intraportal Infusion in Rats  
 Abstract    20 min after intraportal infusion of diethyl phosphate (DEP) in rats, the mitochondrial cardiolipin (CL; 1,3-bisphosphatidyl glycerol) fraction is labelled with DEP. The obtained mixture of CL and DEP-labelled CL, which up to now has not been separated, behaves chromatographically (fractogel; HPLC; TLC), in respect to release of DEP and also in respect of the 31P NMR spectrum as a mixture of CL and cardiolipin ketone diethylenol phosphate. The latter compound was also obtained by photochemical reaction of CL ketone with diethyl phosphoric acid. After cautious hydrogenation (palladium charcoal) of the total mitochondrial lipid fraction of rats treated with DEP and subsequent extraction with NaCl solution (0.005 mol/1), glycerol-2-DEP has been identified in the water phase. It is supposed that this phosphoric acid derivative is formed from CL-DEP by elimination of two molecules of phosphatidic acid. 
  Reference    Z. Naturforsch. 49c, 657—664 (1994); received May 16/ July 6 1994 
  Published    1994 
  Keywords    Mitochondria, Cardiolipin, Cardiolipin Ketone, High-Energy Phosphate, Diethyl Phosphate 
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 Identifier    ZNC-1994-49c-0657 
 Volume    49 
100Author    Meinrad Boll3, LutzW D W Eberb, A.Ndreas Stampflb, Burkhard Messner3Requires cookie*
 Title    Lipogenic Enzymes of Rat Liver and Adipose Tissue. Dietary Variations and Effect of Polychlorinated Biphenyls  
 Abstract    The lipogenic enzymes fatty acid synthase (FAS; EC 2.3.1.85), citrate cleavage enzyme (CCE; EC 4.1.3.8), malic enzyme (ME; EC 1.1.1.40), glucose-6-phosphate dehydrogenase (G6PDH; EC 1.1.1.49) and 6-phosphogluconate dehydrogenase (PGDH; EC 1.1.1.44) were investigated in liver and in brown adipose tissue (BAT) of Wistar rats under various dietary conditions and in the presence of 15 to 250 ppm (approximately 0.045-0.75 [.imol/kg chow) polychlorinated biphenyls (PCBs). In response to refeeding starved animals, enzyme activities in both tissues increased to above normal levels and thereafter exhibited pronounced oscillations of their activities. The extent of increase depended on the carbohydrate and fat content of the diet. The lipogenic enzymes could be grouped in two categories according to their sensitivity to dietary carbo­ hydrate: FAS and CCE responded faster to smaller changes in dietary composition, while ME, G6PDH and PGDH required larger changes and more time to respond. Diet-induced alterations of enzyme activities were of the same order of magnitude in liver and BAT. They were age-dependent, being more pronounced in young animals. Independent of the type of dietary manipulations, activities changed in a coordinate fashion, i.e., the changes of the activities of all 5 enzymes occurred at similar ratios to each other with an identical time course. Feeding PCB-containing diets resulted in a considerable increase of the activities of the lipogenic enzymes in liver, which was significantly greater with ME, G 6PD H and PGDH. The effect was dose-dependent but transient. In liver the response to PCB feeding was iden­ tical in male and female animals, whereas in BAT lipogenic activities increased in females, but decreased in males. Refeeding starved animals with a PCB-containing diet led to an additional stimulation of the normal refeeding-induced increase of the enzyme activities in liver and BAT. This PCB-induced increase was 2-fold for FAS and CCE, but up to 15-fold for the other enzymes. All PCB-induced effects were significantly less pronounced in old than in young animals. In primary hepatocytes activities increased in hormone-free medium in the presence of PCBs. While activity was induced in insuline-and triiodothyronine-containing medium, this increase was significantly greater with PCBs present. 
  Reference    Z. Naturforsch. 49c, 665—678 (1994); received May 5/July 14 1994 
  Published    1994 
  Keywords    Lipogenic Enzymes, Rat Liver, Brown Adipose Tissue, Hepatocytes, Polychlorinated Biphenyls 
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 TEI-XML for    default:Reihe_C/49/ZNC-1994-49c-0665.pdf 
 Identifier    ZNC-1994-49c-0665 
 Volume    49 
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