Screening of the essential oil of Thapsia garganica subsp. messanensis (Guss.) Brullo & al., an endemic plant of Sicily (Italy).

The genus Thapsia L., belonging to the Scandiceae tribe of the Apiaceae family, is mainly distributed in the Mediterranean area, North Africa, and the Iberian Peninsula. The use of plants of this genus in popular medicine dates back to the age of ancient Greeks. In the present study the chemical composition of the essential oil from aerial parts of Thapsia garganica subsp. messanensis (Guss.) Brullo & al., an endemic plant of Sicily, never previously investigated, was evaluated by GC-MS. The main components of its essential oil (Tgm) were 1,4-dimethylazulene (17.0%), chamazulene (10.1%), 3-methyl nonane (7.0%), and butyl heptanoate (4.6%). The comparison with all the other studied essential oils of the genus Thapsia is discussed.

Paeonia mascula subsp. russoi (biv.) Cullen & Heywood: the chemical composition of the aerial parts essential oils of two different populations collected in Sicily (Italy).

In the present study, the chemical composition of the essential oil from aerial parts of two populations of Paeonia mascula subsp. russoi, collected in Sicily, was evaluated by GC-MS. No previously phytochemical investigation has been reported for this subspecies. The main components of the essential oil of the population with pink flowers were salicylaldehyde (34.31%), nonanal (16.95%) and 2-hexenal (10.17%), whereas essential oil of the population with white flowers, was shown to be rich of myrtanal (14.14%), eugenol (14.02%) and salicylaldehyde (12.21%). Furthermore, a complete literature review, not present in literature, on the composition of the essential oils of all the other taxa of Paeonia, studied so far, was performed. PCA and HCA analyses of the composition of essential oils obtained from the aerial parts were also carried out.

The chemical composition of the aerial parts essential oils of Centaurea erycina (Asteraceae), an endemic species of Sicily (Italy).

In the present study, the chemical composition of the essential oil from aerial parts of a very rare Centaurea species, not previously investigated, Centaurea erycina Raimondo and Bancheva, collected in Sicily, was evaluated by GC-MS. The new species, classified just twenty years ago, belongs to Centaurea cineraria group (sect. Pannophyllum Hayek, Asteraceae) and grows in an extremely limited area in the NW part of Sicily. The oil was shown to be rich of aldehydes (41.4%) and sesquiterpenes (33.4%). The main components of the essential oil were ß-caryophyllene (13.4%), caryophyllene oxide (12.6%), hexanal (11.9%), and trans-2-hexenal (10.0%). Furthermore, a complete literature review on the composition of the essential oils of all the other taxa of Centaurea, belonging to sections Pannophyllum, studied so far, was carried out.

The chemical composition of the aerial parts essential oil of Pulicaria odora (L.) Rchb. growing in Sicily (Italy).

The genus Pulicaria Gaertn. (Asteraceae) comprises more than ninety-two species as annual or perennial herbs or small shrubs, distributed in Africa, Europe, and Asia, and concentrated mainly in the Mediterranean region. Several species have been used in the traditional medicine of many countries. In the present study the chemical composition of the essential oil from aerial parts of Pulicaria odora (L.) Rchb., present in the Mediterranean region and collected in Sicily, was analysed by GC-MS. No papers have been previously published on the essential oil of the aerial part of this species. The result showed the presence of large quantity of carbonyl compounds (25.29%), oxygenated sesquiterpenes (23.28%) and thymol derivatives (16.76%). Chemical considerations with respect of other oils of Pulicaria taxa were carried out.

Chemical composition of the essential oils of three taxa of Cytisus growing wild in Sicily, Italy.

The genus Cytisus is native Canary Islands, Europe to Mediterranean, Morocco, Algeria and Tunisia and several species of the genus are used in folk medicine of different countries. In this work the chemical composition of the essential oils from the aerial parts of three taxa of this genus growing wild in Sicily, Cytisus scoparius (L.) Link, C. villosus Pourr. and C. aeolicus Guss., has been investigated. No one report has been published on the Sicilian accession of the former two species, and, at the best of our knowledge, C. aeolicus is devoid of any chemical investigation. Cytisus scoparius and C. aeolicus essential oils have similar composition characterised by the occurrence of almost the same amount of compounds belonging to "other" class (59.5-52.0%) and carbonyl compounds (22.2-19.6%). Cytisus villosus showed a different composition with hydrocarbons as the main class (52.0%), totally absent in the other two species.

The chemical composition of the aerial parts essential oil of Jacobaea delphiniifolia (Asteraceae) growing in Sicily (Italy).

Jacobaea is a small genus of plants belonging to Asteraceae family, formerly joint to Senecio genus, that includes more than 60 species and sub-species. Several taxa of this genus have been extensively studied both for their non-volatile and volatile metabolites. In the present study the chemical composition of the essential oil (EO) from aerial parts of Jacobaea delphiniifolia (Vahl) Pelser & Veldkamp, collected in Sicily, was analyzed by GC-MS. No one report has been previously published on the EO of this species. The result showed the presence of a large quantity of two metabolites, namely 1-undecene (63.57%) and thymol methyl ether (13.65%). Chemotaxonomic considerations were carried out by comparing the other oils of Jacobaea taxa studied so far.

Sicilian Populations of Capparis spinosa L. and Capparis orientalis Duhamel as Source of the Bioactive Flavonol Quercetin.

The genus Capparis is a taxon of difficult delimitation that has several species and ecotypes due to its wide heterogeneity, its extreme phenotypic diversity, and the presence of intermediate forms linked to hybridization phenomena. The Sicilian territory hosts numerous wild and cultivated populations of two spp. Capparis spinosa L. and Capparis orientalis Duhamel, which are ecologically and morphologically distinct. The caper has considerable interest and economic value for its medicinal properties, culinary uses, and cultivation characteristics. It is one of the foods with the highest quercetin content. Quercetin is a flavonol with antioxidant, anti-inflammatory, and immunostimulant properties. Recently, patents and clinical studies have highlighted the inhibitory effect of this compound against several SARS-CoV-2 enzymes (MPro, PLPro, and RdRp). Therefore, the aim of this study was to quantify the amount of quercetin in C. spinosa and C. orientalis by LC-ESI/QTrap/MS/MS and to correlate it with the pedoclimatic features. The results obtained showed that quercetin is more abundant in C. orientalis than in C. spinosa. The highest values of quercetin were recorded in C. orientalis flowers, leaves, and flower buttons of volcanic islands with southwest and east warm exposures. In conclusion, the data acquired can provide a good basis for further scientific investigations to support the identification of possible ecotypes as a source of quercetin for food or pharmaceutical purposes.

The essential oil compositions of three Sicilian accessions of Viscum album L. growing on three different host trees.

Viscum album L., (Common Mistletoe), is a hemiparasitic shrub that lives on a wide range of woody plant species, known since Neolithic period for its ritual and for pharmacological properties. Up to now, no investigation has been reported on the chemical composition of the essential oils of V. album aerial parts in relation with the diverse host trees. Consequently, the essential oils compositions of three Sicilian accession of V. album, growing on Quercus suber L., Crataegus monogyna Jacq. and Olea europaea L. var. europaea cv. 'Santagatese', respectively, were evaluated by GC-MS. The three populations showed quite different profiles indicating that the nature of the host considerably influences the chemical composition of the guest plant, V. album.