Search results for " asteraceae"
showing 10 items of 27 documents
Ptilostemon greuteri Raimondo et Domina in: Schede per una Lista Rossa della Flora vascolare e crittogamica Italiana
2012
Phytochemical analysis ofAchillea ligusticaAll. from Lipari Island (Aeolian Islands)
2016
A complete chemical investigation of Achillea ligustica All. growing at Lipari (Aeolian Island, Sicily) has been carried out. Seventeen metabolites have been isolated and characterised from dichloromethane and methanol extracts of flowers and aerial parts, and GC/MS analyses of petroleum ether extracts was carried out, revealing a composition in sesquiterpenoids similar to those reported for populations from Greece, Sicily and Algeria, showing the presence of (3RS,6RS)-2,6-dimethyl-1,7-octadiene-3,6-diol (1), 2,6-dimethyl-octa-3(E),7-diene-2,6-diol (2), iso-seco-tanapartholide (3) from DCM fraction. In addition from the methanolic extract of the aerial parts, peculiar flavonoid glucuronides…
Cytotoxic activity of some natural and synthetic guaianolides
2005
Several natural guaianolides and synthetic derivatives of repin (1) were tested and found to be active against tumor cell replication. Repin (1) and both mono- and di-halohydrin analogues (2, 7-9, 11, 12) showed significant antitumor potency. A more effective compound (17) was obtained by esterificating repin with the paclitaxel side chain.
Volatile components of aerial parts of Centaurea nigrescens an C. stenolepis growing wild in the Balkans
2010
The volatile constituents of the aerial parts of Centaurea nigrescens Willd, collected in Romania and of two samples of C. stenolepis A. Kerner from Bulgaria and Romania were obtained by hydrodistillation and analyzed. The main components of C. stenolepis were caryophyllene oxide (6.9-15.6%), hexahydrofarnesyl acetone (6.5-4.4%), heptacosane (6.0-4.9%) and p-vinyl guiacol (4.3-5.0%). The main components of C. nigrescens were caryophyllene oxide (9.9%), β-eudesmol (9.5%), spathulenol (7.6%), heptacosane (6.1%) and p-vinyl guiacol (5.5%). The chemotaxonomic significance with respect to their co-location in Sections Lepteranthus and Nigrescentes, respectively, is discussed.
LA VALORIZZAZIONE DELLA FLORA SPONTANEA ATTRAVERSO LO STUDIO DI NUOVI BIOPESTICIDI: ARTEMISIA ARBORESCENS L.
2012
Il termine “biopesticidi” identifica un vasto insieme di molecole, sintetizzate naturalmente da piante od altri organismi vegetali, in grado di manifestare un’attività biologica nei confronti di agenti fitopatogeni di diversa origine, quali virus, batteri, funghi, artropodi ed altri. Tale attività può spaziare dalla semplice repressione di un particolare stadio di sviluppo del patogeno (sporulazione, crescita vegetativa, riproduzione) fino alla induzione di reazioni e processi metabolici che ne determinano la morte. Negli ultimi anni sono stati proposti molti nuovi formulati con queste caratteristiche, la cui diffusione, pur se ancora contenuta, si presenta in continua espansione. Verso que…
Morfologia, cariologia e anatomia fogliare nel genere Dittrichia Greuter (Asteraceae)
2004
All five species of the genus Dittrichia were examined as regards their morphology, karyology and anatomy particularly referred to the leaf istology and micromorphology. Two different analytical keys were elaborated basing on morphological features and leaf anatomy and micromorphology characters.
BIOTECHNOLOGICAL APPROACHES TO THE GENETIC IMPROVEMENT OF CHRYSANTHEMUM CINERARIAEFOLIUM L.
2011
The interest in sustainable agriculture has increased the demand of plant-derived compounds which can be less toxic both to mammals and to the environment than the synthetic agrochemicals. Chrysanthemum cinerariaefolium L. (Asteraceae), commonly termed pyrethrum, is an economically important crop from highlands of tropical and subtropical regions of the world. It is grown for the extraction of pyrethrins, natural insect repellents of plant origin. Pyrethrins are a mixture of six compounds produced by esterification of two acids (chrysanthemic and pyrethric acid) with three mono-terpene-alcohols (pyrethrolone-5, jasmolone-3 and cinerolone-4). The principale source of pyrethrins are the dried…
Chemical composition of the essential oil of Jacobaea maritima (L.) PelserMeijden and Jacobaea maritima subsp. bicolor (Willd.) B. Nord.Greuter (Aste…
2015
In this study, the chemical compositions of the essential oils from aerial parts (JmA) and radices (JmR) of Jacobaea maritima (L.) Pelser & Meijden, collected in Croatia, and of Jacobaea maritima subsp. bicolor (Willd.) B. Nord. & Greuter, collected in Sicily, were evaluated by using gas chromatography and gas chromatography–mass spectrometry. The main components of the essential oil from J. maritima, both in JmA and JmR, were pentacosane (15.7%), heptacosane (13.1%) and nonacosane (8.1%) whereas the essential oil from J. maritima subsp. bicolor was characterised by the presence of hexadecanoic acid (14.6%), caryophyllene oxide (9.3%) and hexahydrofarnesylacetone (6.5%). The comparison of t…
Strategie di gestione delle popolazioni di Calendula maritima Guss. (Asteraceae)
2011
Dopo avere brevemente esaminato la situazione in cui si trovano le popolazioni naturali di C. maritima, specie rara ed endemica della provincia di Trapani (Sicilia), si discute delle più opportune strategie di gestione al fine di assicurarne la conservazione. Vengono infine identificate le principali minacce e proposte le conseguenti necessarie azioni di tutela.
Volatile components from flowers of Centaurea nicaeensis All., C. parlatoris Helder, C. solstitialis L., ssp. schouwii (DC.) Dostàl wild growing in S…
2008
The volatile constituents of the flowerheads of Centaurea nicaeensis All., C. parlatoris Helder and C. solstitialis L. ssp. schouwii (DC.) Dostal were extracted by hydrodistillation and analysed by GC and GC-MS. Altogether 113 components were identified. Fatty acids and hydrocarbons were the most abundant components in the oils. Caryophyllene and caryophyllene oxide were the main compounds of the sesquiterpene fraction. The study on the biological activity of the oils shows no significant activity.