Search results for "Isoplexis"
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LC-NMR applied to the characterisation of cardiac glycosides from three micropropagatedIsoplexisspecies
2002
Species of the genus Isoplexis are of particular interest with respect to the biochemical pathway leading to the cardenolides. It is important to determine whether or not 5β-configured compounds, typically produced by Digitalis species and used in medicine, are present together with their respective α-isomers in Isoplexis spp. Structure elucidation by LC-NMR of the products isolated from in vitro regenerated Isoplexis canariensis, I. chalcantha and I. isabelliana was carried out, and similarities were observed among the products of the three species, including the presence of digitoxigenin-type cardenolides in I. canariensis and xysmalogenin and canarigenin derivatives in I. chalcantha neve…
Ornithophily on the Canary Islands
1984
(1) On the Canary Islands and Madeira typical bird-flowers occur in at least twelve species of six genera, although true flower-birds are absent. This inconsistency is in part elucidated by field observations on exotic and wild plants of Tenerife. —(2) In the Botanical Garden of Orotava it could be observed that various ornithophilous plants, which were introduced there, were visited by indigenous birds for nectar and in one case (Orthostemon) for food tissue. Of the three bird species involved, an endemic race of Chiffchaff (Phylloscopus collybita) and resident Blackcaps (Sylvia atricapilla) exploit, and pollinate, flowers legitimously, while the Wild Canary (Serinus canaria) is predominan…