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'F luorescence' in keywords
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1986 (1)
1984 (3)
1Author    O. Tto, O. Lfb, Onowara Begum2, Hans GeigerbRequires cookie*
 Title    Fluorescence Properties of Hydroxy-and Methoxyflavones and the Effect of Shift Reagents  
 Abstract    The fluorescence spectra o f 42 hydroxy-and m ethoxyflavones in m ethanol solution have been investigated. The follow ing findings are considered to be useful in structure elucidation and identification o f flavonoids: (a) The maxima of the absorption and fluorescence bands give, in m ost cases, a unique combination; (b) flavones exhibit exceptionally large Stok es' shifts (6,800 to 
  Reference    Z. Naturforsch. 39b, 231 (1984); received Septem ber 23 1983 
  Published    1984 
  Keywords    Flavonoids, F luorescence, Structure Elucidation, Shift Reagents 
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 TEI-XML for    default:Reihe_B/39/ZNB-1984-39b-0231.pdf 
 Identifier    ZNB-1984-39b-0231 
 Volume    39 
2Author    O. Tto, S. W. Olfbeis, Eva Fiirlinger3, HemC. Handra Jhab, Fritz ZillikenbRequires cookie*
 Title    The Absorption and Fluorescence of Isoflavones and the Effect of Shift Reagents  
 Abstract    The absorption and fluorescence maxima o f 20 isoflavones have been determ ined in methanol solution and the effect o f addition o f w ater, 50% sulfuric acid, aluminium trichloride, borax, sodium acetate, ammonia and sodium hydroxide has been studied. The following findings may be useful in the structure elucidation o f naturally occurring isoflavones: (a) 5-Hydroxyisoflavones have band I absorption maxima around 335 nm. 6-hydroxyisoflavones betw een 310 and 330 nm, 
  Reference    Z. Naturforsch. 39b, 238 (1984); received Septem ber 23 1983 
  Published    1984 
  Keywords    Isoflavonoids, F luorescence, A bsorption, Shift Reagents 
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 TEI-XML for    default:Reihe_B/39/ZNB-1984-39b-0238.pdf 
 Identifier    ZNB-1984-39b-0238 
 Volume    39 
3Author    K. H. GrumbachRequires cookie*
 Title    Herbicides which Interfere with the Biosynthesis of Carotenoids and Their Effect on Pigment Excitation, Chlorophyll Fluorescence and Pigment Composition of the Thylakoid Membrane  
 Abstract    Plants grown in the presence o f the herbicides assayed synthesized chlorophylls during growth at low fluence rates. Subsequent irradiation with higher fluence rates o f red light induced a strong chlorosis with SAN 6706 being a much stronger herbicide than J 852 or am ino-triazole. All herbicides assayed also changed the content and com position o f chlorophylls, carotenoids and pigment-protein-complexes o f the thylakoid m em brane and therefore the pigm ent excitation and chlorophyll fluorescence em ission spectra o f the plastid. W ith increasing herbicide toxicity the main characteristic em ission bands at 690 and 730 nm disappeared and new em ission bands at 715 (J 852) and 700 nm (SA N 6706) appeared. Such "artificial" m em branes with a changed pigment composition were very susceptible to light. Presented data m ay be taken as evidence, that the lack o f photoprotective cyclic carotenoids caused by the specific action o f a bleaching herbicide is the primary event that m ay lead to a disturbed form ation o f the thylakoid membrane and its destruction by light and oxygen. 
  Reference    Z. Naturforsch. 39c, 455—458 (1984); received N ovem ber 29 1983 
  Published    1984 
  Keywords    Bleaching Herbicides, Carotenoids, Chlorophylls, F luorescence, Pigm ent Excitation 
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 TEI-XML for    default:Reihe_C/39/ZNC-1984-39c-0455.pdf 
 Identifier    ZNC-1984-39c-0455 
 Volume    39 
4Author    R. Steiner, A. A. Ngerhofer+, H. ScheerRequires cookie*
 Title    The Photosynthetic Apparatus of Ectothiorhodospira halochloris 2. Accessibility of the Membrane Polypeptides to Partial Proteolysis and Antenna Polypeptide Assignments to Specific Chromophores  
 Abstract    E. halochloris thylakoids and spheroplasts were treated with trypsin, thermolysin or proteinase K to determ ine which proteins are exposed at the different m embrane surfaces. B ased on SD S polyacrylamide analysis, all 9 polypeptides are exposed on the cytoplasm ic side. O nly one (28 k D a) is accessible from the periplasmic side. This polypeptide is generally isolated as the H-subunit o f the reaction centers of photosynthetic bacteria, but is in the case o f E. halochloris rather isolated with the antenna (B 800/1020) (Steiner and Scheer, Biochim . Biophys. A cta 807, 278, 1983). Proteolysis is accom panied by a shift of the absorption band at longest w avelengths from 1020 to 960 nm (B 800/960), which upon standing is shifted further to 680 nm ("B " 800/680). The spectral changes are similar to the ones reported earlier for treatm ent with acid, and are also inducible with urea. The correlation o f SD S-P A G E and absorption spectroscopy show s, that the chrom ophores absorbing at 1020 nm are transformed sim ultaneously with the degradation o f the 6.5 kD a (— a) polypeptide. 
  Reference    Z. Naturforsch. 41c, 571 (1986); received January 9 1986 
  Published    1986 
  Keywords    Bacterial Photosynthesis, Ectothiorhodospira, M embrane T opology, A ntenna Polypeptides, F luorescence, Circular D ichroism, Energy Transfer 
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 TEI-XML for    default:Reihe_C/41/ZNC-1986-41c-0571.pdf 
 Identifier    ZNC-1986-41c-0571 
 Volume    41