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Clara Fredeline Rajemiarimoelisoa Cédric Boyère Léonie Pellissier Marine Peuchmaur Hanitra Ranjana Randrianarivo Danielle Aurore Doll Rakoto 《Natural product research》2016,30(13):1557-1560
In this study, we report for the first time the presence of alkaloids belonging to β-carboline type in the pods of the endemic Albizia polyphylla from Madagascar. Three major alkaloids were isolated and structurally identified as: 1-methyl-β-carboline, (+)-(R)-1-methyl-1,2,3,4-tetrahydro-β-carboline and (–)-(S)-1,2-dimethyl-1,2,3,4-tetrahydro-β-carboline. 相似文献
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Mika Hayashi Maximo Larry Lopez Caceres Yoshihiro Nobori Byambasuren Mijidsuren Jens Boy 《Isotopes in environmental and health studies》2013,49(6):608-621
ABSTRACTIn the last decades a drastic increase in air temperature but a stable precipitation regime in Mongolia has led to gradual drying conditions. Thus, we evaluated the effect of spatial and climatic characteristics on the soil–plant nitrogen dynamics in three representative larch stands (Larix sibirica) with different geographical and climatic conditions using stable nitrogen isotopes. The results showed significant differences in the soil inorganic N content among sites and consequently a different isotopic composition in the plant–soil system. Litter, bark and wood had the lowest δ15N values for all sites, slightly higher δ15N values for needles, while the highest δ15N values were observed for roots and soil. These differences could be the result of the larch stands age themselves, but were in agreement with the spatial and climatic characteristics of the sites. Based on the δ15N value a higher reliance on ectomycorrhizal fungi (ECMF) was observed in the warmest and driest site, while lower dependency was shown in the cooler northern site with higher soil inorganic N content. In both sites, the rate of air temperature increase has been similar in the last decades; however, their soil–plant N dynamics showed different characteristics. 相似文献
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