Evidence for the existence and spatial distribution of a chemical variability in Helleborus multifidus vis. subsp. istriacus (Schiffner) Merxm. & Pod. in the North-Adriatic Karst region

Helleborus multifidus subsp. istriacus is an endemic Illyric Dalmatian species, that in the North-Adriatic area occurs at the border between Italy and Jugoslavia. The entity produces two bufadienolides (hellebrin and glucohellebrin) in the hypogeal organs. Three types of population are identified on the basis of their quantitative variations and their distributive ratio between roots and rhizomes. Their ranges have been estabilished on a 140 Km 2 area near Trieste (Friuli-Venezia Giulia). This distribution patterns seem to be related with a gradient in water availability. The correlation between phytochemical variability and variation of climatic factors, suggest that the investigated substances could have an adaptative value in respect with the ecology of the Helleborus entity

Phytosterols in some species of Euphorbia L.

In five species of Euphorbia of the Friuli-Venezia Giulia region (NE Italy) (E. amygdaloides, E. cyparissias, E. helioscopia, E. fragifera and E. fl.avicoma subsp. verrucosa) ten phytosterols were isolated and identified, by means of HPLC and spectroscopic tecniques, as β-sitosterol, stigmasterol, campesterol, colestan -3, 5, 6-triol, cycloartenol, squalene, stigmastanol, stigmasterol acetale, cholesterol and lanosterol. The ratio β-sitosterol/stigmasterol can be used to distinguish some of the species

Terpenes of Salvia species leaf oils: chemosystematic implications

Wild specimens of Salvia L. were collected in three different moments of anthesis and their volatile leaf oils were analyzed by GC/GCMS. The quantitative terpene composition is very variable with the anthesis. S. bertolonii is the richest species in a-thujone. S. officinalis is characterized by high percentages of 1,8 cineole, 4-terpineol, isorboneol and a -bisabolol. In S. verticillata high percentages of borneol and {3-cariophyllene are present. In the three species a-thujone was always more abundant than ß-thujone. The three taxa are characterized by peculiar combinations of terpenoids. The multivariate analysis of the chemical data indicates the degree of affinity between the three taxa and their chemotaxonomical status. Some components of Salvia essential oil have pharmaceutical activities

Taxonomical studies on Seseli elatum l. And allied species. - i. Systematic implications of some morpho-anatomical characters

In the Friuli-Venezia Giulia Region (NE-Italy) three populations of Seseli elatum agg. occur, which have different altitude ranges and different ecology. It is generally difficult to distinguish these three taxa by classical taxonomical characters. This paper presents a first contribution to the solution of the problem. We have examined the classical morphological characters, plus microcharacters of the fruit surface (SEM), and the secretory structures (canals, ampullae, vittae). We propose some new discriminant characters. The morpho-anatomical variation seems to be correlated with a gradient of decreasing temperature and aridity, and increasing elevation. The anatomical variation corresponds with variation in the biochemical production. The numerical classification of ali characters indicates a rather isolated position of the population which occurs in xerophytic plant associations at low altitude

Chemosystematic value of aristolochic acids in the genus aristolochia l. in Friuli-Venezia Giulia (NE Italy)

The composition of aristolochic acids from different populations of four Aristolochia species was analysed by HPLC; quantitative data were submitted to discriminant and statistical analyses. The interspecific variability was confirmed, and significant differences were detected by canonical discriminant functions. The aristolochic acid II and the ratio AAII/AAI are significant in the discrimination of the examined species

Analisi morfologiche e citotassonomiche su alcune entità di Helleborus l. sect. Helleborus nel Friuli-Venezia Giulia

MORPHOLOGIC AND CYTOTAXONOMIC INVESTIGATIONS ON SOME TAXA OF HELLEBORUS SECT. HELLEBORUS IN THE FRIULI-VENEZIA GIULIA REGION (NORTHEASTERN ITALY) AND ISTRIA On the basis of morphometric, histoanatomic and cytotaxonomic analyses, the populations of Helleborus of the Trieste Karst region (North-Eastern Italy) and Istria with smaller floral diameter (4.4-4.8 cm), currently treated as H. multifidus subsp. istriacus, are here included into the H. odorus complex

Indagine sul contenuto di colchicina in Colchicum autumnale L. dell'Italia settentrionale

The colchicine content in Colchicum autumnale L. of North Italy. The colchicine content of different parts (bulb, flower, leaves, seeds, capsules) of C. autumnale L. has been identified. The specimens were collected in North Italy, in stations with different altitudinal, climatic and vegetational conditions. Colchicine is present in all the studied parts, with a concentration gradient going from a maximum in the seeds to a minimum in the bulbs. The colchicine content in the bulbs varies according to the principal phases of the life-cycle (flowering, fruiting, hudding), whereas in the seeds it depends from the degree of ripeness, being higher in the first stages. On the basis of results, it is suggested to take into consideration also leaves and flowers for the extraction of the alkaloid