Maria Cecilia Loi

Medical ethnobotany of the Tabarkins, a Northern Italian (Ligurian) minority in south-western Sardinia

A medico-ethnobotanical study was conducted among the Tabarkin communities living in Calasetta and Carloforte, in south-western Sardinia. These communities represent a Ligurian minority who have resided in Sardinia since their forebears migrated from Tabarka in Tunisia in the second half of the 18th Century, having previously migrated to Tabarka from Genoa in 1544. In this study, we conducted more than 200 interviews and recorded 53 botanical taxa and 72 folk pharmaceutical preparations, which represent the folk medicine of the Tabarkins. The folk phytotherapy of the Tabarkins living in Calasetta and Carloforte is quite restricted compared with other folk phytotherapy recorded in similar recent ethnobotanical studies conducted in Sardinia. This could indicate that there has been a remarkable erosion of Traditional Knowledge (TK) within these two communities. Of particular interest are a few local medical uses we recorded that have never or only very rarely been documented in Italy; namely the use of Dittrichia graveolens (L.) Greuter as an anti-haemorrhoidal, of Centaurea calcitrapa L. as a remedy for malaria, of Glycyrrhiza glabra L. in ophthalmic treatments, and of Urtica dioica L. as an antiviral in cases of German measles. Most of the botanical species quoted in this research are referred to in the two centres using a local Ligurian idiom. Most of the medico-botanical uses we recorded are very similar to those collected in other ethnobotanical surveys carried out in Liguria and south-western Sardinia. Because there was no evidence in this research of any substantial ethnobotanical traces related to the communities’ North-African experience, it would appear that the Tabarkins have readily adopted their host culture’s use of medicinal plants and have retained their own traditional cognitive concepts and knowledge of the natural plant world through the language only.

Analysis of pharmaceutically relevant taxoids in wild yew trees from Sardinia.

Needles from a series of wild yews (Taxus baccata L.) from Sardinia were investigated for their contents of 10-deacetyl baccatin III (DAB-III, 1), paclitaxel (Taxol) (2) and taxine (3). Despite a common geographical origin, ample variation of the taxoid profile was discovered, and several samples were surprisingly devoid of all terpenoid markers above. This finding is unprecedented within the European yew, while the general lack of taxine might rationalize the observation that most plants investigated are actively and impunently browsed by goats.

Antidepressant activity of Ceratonia siliqua L. fruit extract, a source of polyphenols

A previous study from our laboratory has shown the facilitatory effect of Ceratonia siliqua L. (Fabaceae) on the dopaminergic function. This study investigates the involvement of monoamines in the antidepressant activity of the total polyphenol content of Ceratonia siliqua extract (CS) in mice using a tail suspension test (TST) and forced swim test (FST). The immobility time in the TST and FST were significantly reduced by CS (25 and 50 mg kg−1, i.p.). The extract considerably attenuated the duration of immobility induced by prazosin (62.5 µg kg−1, i.p., an α-adrenoceptor antagonist) and eticlopride (0.1 µg kg−1, i.p., a classical D2-like dopamine receptor antagonist) in both TST and FST, whereas the extract could not modify the immobility in mice treated with p-chlorophenylalanine (100 mg kg−1, i.p., ×3 days; an inhibitor of serotonin synthesis) and baclofen (10 mg kg−1, i.p., GABAB agonist). This suggests that the antidepressant effect of CS is mediated by dopamine and noradrenaline.

Phytochemical investigation on Atriplex halimus L. from Sardinia

In this study, we reported the phytochemical composition of the aerial parts of Atriplex halimus L. collected from Sardinia. This species is a halophytic shrub, typical of the Mediterranean Basin. Four new glycosylated flavonoids were isolated and their structures were elucidated on the basis of 1D, 2D NMR and MS spectra as 3′,5′-dimethoxymyricetin-3-O-β-d-xylopyranosyl-7-O-fucopyranosyl-(1 → 3)-β-d-glucopyranoside (1), 3′-methoxyquercetin-7-O-β-d-fucopyranosyl-(1 → 3)-β-d-glucopyranosyl-3-O-β-xylopyranosyl-(1 → 4)-β-xylopyranoside (2), 3′-methoxyquercetin-7-O-α-l-rhamnopyranosyl-3-O-α-arabinofuranosyl-(1 → 6)-β-d-glucopyranoside (3) and 3′,5′-dimethoxymyricetin-7-O-fucopyranosyl-(1 → 3)-β-d-glucopyranoside (4). LC-MSn analysis on the extract revealed the presence of other myricetin, quercetin, isorhamnetin glycosides, simple phenolic acids and esters.