Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Separation and quantitation of molecular species from plant lipids by high-performance liquid chromatography
    Amsterdam : Elsevier
    Analytical Biochemistry 144 (1985), S. 319-328 
    Details
    ISSN: 0003-2697
    Keywords: double bonds ; glycolipids ; gradient elution ; p-anisoyl diacylglycerols ; phospholipids ; uv absorption coefficients
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1016/0003-2697(85)90124-1
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Seasonal differences in isoprene and light-dependent monoterpene emission by Amazonian tree species (2004)
    Oxford, UK : Blackwell Science Ltd
    Global change biology 10 (2004), S. 0 
    Details
    ISSN: 1365-2486
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering , Geography
    Notes: Whereas for extra-tropical regions model estimates of the emission of volatile organic compounds (VOC) predict strong responses to the strong annual cycles of foliar biomass, light intensity and temperature, the tropical regions stand out as a dominant source year round, with only little variability mainly due to the annual cycle of foliar biomass of drought-deciduous trees. As part of the Large Scale Biosphere Atmosphere Experiment in Amazônia (LBA-EUSTACH), a remote secondary tropical forest site was visited in the dry-to-wet season transition campaign, and the trace gas exchange of a strong isoprene emitter and a monoterpene emitter are compared to the wet-to-dry season transition investigations reported earlier. Strong seasonal differences of the emission capacity were observed. The standard emission factor for isoprene emission of young mature leaves of Hymenaea courbaril was about twofold in the end of the dry season (111.5 μgC g−1 h−1 or 41.2 nmol m−2 s−1) compared to old mature leaves investigated in the end of the wet season (45.4 μgC g−1 h−1 or 24.9 nmol m−2 s−1). Standardized monoterpene emission rate of Apeiba tibourbou were 2.1 and 3.6 μgC g−1 h−1 (or 0.3 and 0.8 nmol m−2 s-1), respectively. This change in species-specific VOC emission capacity was mirrored by a concurrent change in the ambient mixing ratios. The growth conditions vary less in tropical areas than in temperate regions of the world, and the seasonal differences in emission strength could not be reconciled solely with meteorological data of instantaneous light intensity and temperature. Hence the inadequacy of using a single standard emission factor to represent an entire seasonal cycle is apparent. Among a host of other potential factors, including the leaf developmental stage, water and nutrient status, and abiotic stresses like the oxidative capacity of the ambient air, predominantly the long-term growth temperature may be applied to predict the seasonal variability of the isoprene emission capacity. The dry season isoprene emission rates of H. courbaril measured at the canopy top were also compared to isoprene emissions of the shade-adapted species Sorocea guilleminiana growing in the understory. Despite the difference in VOC emission composition and canopy position, one common algorithm was able to predict the diel emission pattern of all three tree species.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1529-8817.2003.00771.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Coupling isoprene and monoterpene emissions from Amazonian tree species with physiological and environmental parameters using a neural network approach (2005)
    Oxford, UK : Blackwell Science Ltd
    Plant, cell & environment 28 (2005), S. 0 
    Details
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The ability to predict isoprene emissions from plants is important for predicting atmospheric chemistry. To improve the basis for prediction capability, data obtained from continuous field measurements of isoprene and monoterpene emissions from three Amazonian tree species were related to observed environmental and leaf physiological parameters using a new neural network approach. The environmental parameters included leaf temperature, light, relative humidity, water vapour pressure deficit, and the history of ambient temperature and ozone concentration, whereas the physiological parameters included stomatal conductance, assimilation and intercellular CO2 concentration. The neural approach with 24 different combinations of these parameters was applied to predict the emission variability observed during short time periods (2–3 d) with individual tree branches and, on a longer-term scale, in aggregated data sets from different seasons, leaf developmental stage, and light environment. The results were compared to the quasi standard emission algorithm for isoprene. On the short-term scale, good agreement (r2≈ 0.9) was obtained between observations and predictions of the standard algorithm as well as predictions of the neural network using the same input parameters (leaf temperature and light). When these predictors were used to model the long-term emission variability, r2 was reduced to 〈 0.5 for both approaches. Remarkably, for the neural technique, more than 50% of the unexplained variance could be explained by the mean temperature of the preceding 36 h. An even better network performance was obtained with physiological parameter combinations (r2 〉 0.9) suggesting a strong and applicable link between isoprenoid emission and leaf primary metabolism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-3040.2004.01278.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Strong correlation between isoprene emission and gross photosynthetic capacity during leaf phenology of the tropical tree species Hymenaea courbaril with fundamental changes in volatile organic compounds emission composition during early leaf development (2004)
    Oxford, UK : Blackwell Science Ltd
    Plant, cell & environment 27 (2004), S. 0 
    Details
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Changes of the volatile organic compounds (VOC) emission capacity and composition of different developmental stages of the tropical tree species Hymenaea courbaril were investigated under field conditions at a remote Amazonian rainforest site. The basal emission capacity of isoprene changed considerably over the course of leaf development, from young to mature and to senescent leaves, ultimately spanning a wide range of observed isoprene basal emission capacities from 0.7 to 111.5 µg C g−1 h−1 during the course of the year. By adjusting the standard emission factors for individual days, the diel courses of instantaneous isoprene emission rates could nevertheless adequately be modelled by a current isoprene algorithm. The results demonstrate the inadequacy of using one single standard emission factor to represent the VOC emission capacity of tropical vegetation for an entire seasonal cycle. A strong linear correlation between the isoprene emission capacity and the gross photosynthetic capacity (GPmax) covering all developmental stages and seasons was observed. The present results provide evidence that leaf photosynthetic properties may confer a valuable basis to model the seasonal variation of isoprenoid emission capacity; especially in tropical regions where the environmental conditions vary less than in temperate regions. In addition to induction and variability of isoprene emission during early leaf development, considerable amounts of monoterpenes were emitted in a light-dependent manner exclusively in the period between bud break and leaf maturity. The fundamental change in emission composition during this stage as a consequence of resource availability (supply side control) or as a plant's response to the higher defence demand of young emerging leaves (demand-side control) is discussed. The finding of a temporary emergence of monoterpene emission may be of general interest in understanding both the ecological functions of isoprenoid production and the regulatory processes involved.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-3040.2004.01252.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Biological activities of furostanol saponins from Nicotiana tabacum
    Amsterdam : Elsevier
    Phytochemistry 29 (1990), S. 2485-2490 
    Details
    ISSN: 0031-9422
    Keywords: Nicotiana tabacum ; Solanaceae ; biological activity ; furostanol saponins ; saponin accumulation ; saponin degradation. ; tobacco
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0031-9422(90)85171-B
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Characterization of a membrane bound β-glucosidase responsible for the activation of oat leaf saponins
    Amsterdam : Elsevier
    Phytochemistry 24 (1985), S. 1941-1943 
    Details
    ISSN: 0031-9422
    Keywords: Avena sativa ; Gramineae ; antifungal ; membrane bound ; oat ; saponins ; subcellular localization. ; β-glucosidase
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/S0031-9422(00)83096-4
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Prolamellar-body structure, composition of molecular species and amount of galactolipids in etiolated, greening and reetiolated primary leaves of oat, wheat and rye (1986)
    Springer
    Planta 168 (1986), S. 453-460 
    Details
    ISSN: 1432-2048
    Keywords: Avena (prolamellar body) ; Etioplast ; Galactolipid ; Greening ; Plastid development ; Prolamellar body ; Secale (prolamellar body) ; Triticum (prolamellar body)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The greening and reetiolation process of etiolated leaves of oat, wheat and rye, possessing different types of prolamellar bodies (PLBs), was observed by electron microscopy. Oat is known to possess unusual crystalline PLBs (so-called ‘narrow type’). Rye and what, which normally show PLBs with more loosely packed tubules (‘wide type’) during etiolation, exhibited PLBs of the narrow type after illumination and subsequent reincubation in the dark (=reetiolation). Thus the reetiolated PLBs of wheat and rye did not differ from etiolated or reetiolated oat PLBs. In parallel with the microscopic analysis, intact leaves of all developmental stages were analysed for their galactolipid content and composition of molecular species using a newly developed high-performance liquid chromatography procedure. When oat, wheat and rye were compared, differences in the molecular species and the molar ratio of the two galactolipids monogalactosyldiacylglyceride (MGDG) and digalactosyldiacylglyceride (DGDG) were found. However, no parameter showed a correlation with PLB construction, disintegration or reconstruction. The results presented in this paper are not consistent with the hypothesis that the molar ratio of MGDG/DGDG is responsible for the tubular structure of prolamellar bodies in etioplasts.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00392264
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Biogenic Volatile Organic Compounds (VOC): An Overview on Emission, Physiology and Ecology (1999)
    Springer
    Journal of atmospheric chemistry 33 (1999), S. 23-88 
    Details
    ISSN: 1573-0662
    Keywords: nonmethane hydrocarbons ; volatile organic compounds ; terpenes ; isoprene ; oxygenated compounds ; alkanes ; alkenes ; carbonyls ; acids ; esters ; emission ; physiology ; ecology ; emission inventories ; review
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract This overview compiles the actual knowledge of the biogenic emissions of some volatile organic compounds (VOCs), i.e., isoprene, terpenes, alkanes, alkenes, alcohols, esters, carbonyls, and acids. We discuss VOC biosynthesis, emission inventories, relations between emission and plant physiology as well as temperature and radiation, and ecophysiological functions. For isoprene and monoterpenes, an extended summary of standard emission factors, with data related to the plant genus and species, is included. The data compilation shows that we have quite a substantial knowledge of the emission of isoprene and monoterpenes, including emission rates, emission regulation, and biosynthesis. The situation is worse in the case of numerous other compounds (other VOCs or OVOCs) being emitted by the biosphere. This is reflected in the insufficient knowledge of emission rates and biological functions. Except for the terpenoids, only a limited number of studies of OVOCs are available; data are summarized for alkanes, alkenes, carbonyls, alcohols, acids, and esters. In addition to closing these gaps of knowledge, one of the major objectives for future VOC research is improving our knowledge of the fate of organic carbon in the atmosphere, ending up in oxidation products and/or as aerosol particles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006127516791
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Enzymatic consumption of carbonyl sulfide (COS) by marine algae (2000)
    Springer
    Biogeochemistry 48 (2000), S. 185-197 
    Details
    ISSN: 1573-515X
    Keywords: Amphidinium klebsii (Dinophyceae) ; atmosphere ; CA ; carbonic anhydrase ; carbonyl sulfide ; COS ; Mantoniella squamata (Prasinophyceae) ; marine algae ; Prymnesium parvum (Prymnesiophyceae) ; reduced sulfur compounds ; trace gases
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract We show that the marine algae Mantoniella squamata, Prymnesium parvum, and Amphidinium klebsii take up carbonyl sulfide (COS) from their surrounding medium. Inhibitor studies confirm that this COS uptake is catalyzed by the enzyme carbonic anhydrase, which was not detectable with conventional methods. As shown for M. squamata, the COS uptake can be dependent on the growth conditions. Furthermore, COS uptake shows a clear positive correlation with the COS concentration in the growth medium. The value of K1/2 for the COS uptake was estimated to be around 222 mol/m3. The COS consumption by the marine algae species investigated was estimated to be negligible compared to the photoproduction and hydrolysis of COS in seawater.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006134213995
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Exchange of reduced sulfur gases between lichens and the atmosphere (1994)
    Springer
    Biogeochemistry 26 (1994), S. 25-39 
    Details
    ISSN: 1573-515X
    Keywords: biogeochemical cycling ; carbonyl sulfide ; dimethyl sulfide ; hydrogen sulfide ; lichens ; trace sulfur gas exchange
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract Fourteen lichens, 10 green algal lichens and four cyanolichens, as well as a cyanobacterium emitted significant quantities of H2S (0.01–0.04 pmol g dw−1 s−1) and DMS (0.005–0.025 pmol g dw−1 s−1) but were sinks for COS (0.015–0.14 pmol g dw−1 s−1). In contrast, exchange of CH3SH and CS2 were sporatic and inconsistent. Although some interspecific variation occurred for the first three gases, exchange rates were relatively uniform and were not influenced by irradiance conditions. In contrast to DMS and H2S emission, COS uptake was strongly influenced by degree of thallus hydration. Because lichen dominated systems cover extensive terrestrial habitats, COS uptake is potentially important in the world's sulfur budget.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02180402
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...