Elsa Mariella Cappelletti

Melatonin in plants.

A widespread occurrence of melatonin in plant kingdom has been reported. The circadian rhythm in the level of melatonin observed in both unicellular algae and higher plants, suggests a role in regulation of photoperiodic and rhythmic phenomena, i.e. a similar function for melatonin in both plants and animals. Evidence has been obtained for a role of melatonin in plant morphogenesis, but more research is needed to ascertain other suggested physiological roles in higher plants (seed dormancy regulation, radical scavenger activity, interaction with calmodulin) as well the ecological significance of the high melatonin levels recorded in alpine plants. Setting-up more reliable analytical methods for melatonin detection and quantification is a basic requirement to get more insight into melatonin roles in plant physiology and ecology.

Localization of the cytotoxic hydroperoxyeudesmanolides in Artemisia umbelliformis

Abstract The localization of the cytotoxic hydroperoxyeudesmanolides in Artemisia umbelliformis Lam. (Compositae) was investigated utilizing the histochemical techniques of the colour reactions with acids and with ferrous (II) thiocyanate on samples pre-treated or not with chloroform. All the organs known by chemical analysis to contain sesquiterpene lactones were studied (leaves, twigs, flowers, achenes). A deep red staining with conc. sulphuric acid and a brownish staining with ferrous (II) thiocyanate were observed in the subcuticular space and in the head cells of the biseriate glandular trichomes, and it was shown that for the plant specimens studied these colour reactions are to be considered specific for the sesquiterpenoid hydroperoxides. Based on the results of their localization in the plant as well as on the available experimental evidence on related compounds, a possible ecological significance of the compounds as feeding deterrents and/or allelopathic substances, is suggested.

External antirheumatic and antineuralgic herbal remedies in the traditional medicine of north-eastern italy

The utilization of more than 90 plant species as folk external remedies to treat rheumatic and arthritic diseases is reported, and their possible effectiveness is discussed according to present phytochemical and pharmacological knowledge. Some of the plant species used exhibit skin-irritant properties (protoanemonin, isothiocyanate or allicine yielding plants and species containing capsaicin, oleoresins, volatile oils, resinous principles, alkaloids). The effectiveness of other herbal remedies depends on their content of salicyl derivatives. A considerable number of the plant species utilized contain chemical products (triterpenoid or steroid compounds, alkaloids) for which anti-inflammatory properties have been demonstrated.

Unilateral mydriasis due to Angel's Trumpet

Introduction. There are many causes of bilateral and unilateral mydriasis. Common garden plants, such as Brugmansia (Angels trumpet), contain tropane alkaloids. Case Report. An 11–year-old girl was brought to the Emergency Department because of discomfort and difficulty with near vision in the left eye, accompanied by unilateral mydriasis (pupil approximately 8 mm, unresponsive to both papillary light reflex and accommodation reflex). The consensual papillary light reflex of the right eye, the anterior chambers, the fundi, and the extraocular movements were intact. The history revealed that she had been playing in the garden and had just touched “a nice pink flower, similar to a trumpet.” Treatment was symptomatic and supportive, and the anisocoria resolved 48 hours after exposure. Morphological and chemical investigations showed high amounts of parasympatholytic tropane alkaloids in a corolla area rich in Dargendorff-positive glandular hairs. Discussion. Simple topical exposure to the flowers of Angels trumpet, without instillation of plant sap into the eye, can produce self-limited unilateral mydriasis. Conclusions. This case adds to the differential diagnosis of acute anisocoria in otherwise healthy children. An accurate and detailed history will avoid unnecessary and expensive diagnostic tests. It is important for parents and garden suppliers have information about the potential adverse effects after handling Angels trumpet plants.

Determination of pyrrolizidine alkaloids in Senecio inaequidens D.C. by capillary gas chromatography.

A study of the toxic pyrrolizidine alkaloids contained in Senecio inaequidens D.C., an infestant species of the Senecio genus, widespread in the North East of Italy, is reported. Five of these compounds, senecivernine, senecionine, integerrimine, retrorsine and an analogue of retrorsine, were identified by means of capillary gas chromatography and capillary gas chromatography-mass spectrometry.

Furocoumarin Contents in the Vegetative Organs of Cultivated Psoralea Species

AbstractFurocoumarin content was investigated in the different vegetative organs of several cultivated Psoralea species (P. macrostachya DC, P. onobrychis Nutt., P. glandulosa L. and P. bituminosa L.). The linear furocoumarin psoralen and its angular isomer angelicin are ubiquitously present, although their concentrations vary greatly in different species and plant organs. The vegetative organs of some Psoralea species can be regarded as interesting natural furocoumarin sources, considering their great biomass production. The importance of the co-occurrence of both isomers as chemical markers for the genus Psoralea and of their ratio as a specific character, is confirmed.

Chemical diversity of the contents from the secretory structures of Heracleum sphondylium subsp. Sphondylium

Abstract The lipophilic constituents of ‘companion canals’ and vittae co-occurring in fruits of Heracleum sphondylium L. subsp. sphondylium were investigated by microdissection and subsequent analysis by capillary gas chromatography and capillary gas chromatography-mass spectrometry. The chemical composition of the two different types of secretory structures present in the fruits is different The canals, present in all of the aerial vegetative plant parts and in the fruits, are characterized by mono- and sesquiterpenoids, while the vittae, peculiar to the fruits, contain fatty acid aliphatic esters and furocoumarins.

Somatic embryogenesis and indole alkaloid production in Catharanthus roseus

ABSTRACT A new protocol to obtain an embryogenic cell line from cultured seedling explants of Catharanthus roseus is described. In order to assess the relationship between tissue differentiation and secondary metabolite biosynthesis, the biosynthetic capabilities (alkaloid production) of an embryogenic cell line and two non-embryogenic C. roseus strains were comparatively examined. Faster cell growth rate was associated with higher alkaloid production in the embryogenic cell line. The kinetics of ajmalicine and serpentine production by the three cell lines is also reported.

Production of coumarin compounds by Haplophyllum patavinum in vivo and in vitro

Abstract Native plants, calli and suspension cultures of Haplophyllum patavinum were found to produce several coumarin compounds, eight of which were identified as umbelliferone, scopoletin, 7-isoprenyloxycoumarin, umbelliprenin, osthenol, columbianetin, angelicin and psoralen. Umbelliferone, angelicin and psoralen were found both in plant organs and in tissue cultures, scopoletin and umbelliprenin only in vivo , osthenol, 7-isoprenyloxycoumarin and columbianetin only in vitro conditions. The coumarin production in vitro was strongly affected by the cell strain. The co-occurrence of the linear and the angular furanocoumarins, psoralen and angelicin, had never been previously reported in the genus Haplophyllum .

Production of lignans by Haplophyllum Patavinum in vivo and in vitro

Three known arylnaphthalene lignans (justicidin B, diphyllin and tuberculatin), and one dibenzylbutyrolactone (arctigenin) were isolated from native plants, callus and suspension cultures of Haplophyllum patavinum. The present paper represents the first report on arylnaphthalene lignan production by in vitro cultures; in vitro, the biogenetic potential is strictly dependent on the cell strain.