C. Formisano

Chemical composition and antimicrobial activity of the essential oils from two species of Thymus growing wild in southern Italy.

The volatile constituents of the aerial parts of two samples of Thymus longicaulis C. Presl, collected in Campania and in Sicily, and two samples of Thymus pulegioides L. from the same regions, were extracted by hydrodistillation and analyzed. Considering the four oils together, seventy-eight different compounds were identified: 57 for Thymus longicaulis from Sicily (91.1% of the total oil), 40 for Thymus longicaulis from Campania (91.5% of the oil), 39 for Thymus pulegioides from Sicily (92.5% of the oil) and 29 for Thymus pulegioides from Campania (90.1% of the oil). The composition of the oils is different, although the most abundant components are identical in T. pulegioides. The essential oils showed antibacterial activity against eight selected microorganisms.

Headspace volatile composition of the flowers of Caralluma europaea N.E.Br. (Apocynaceae).

The volatile constituents of the flowers of Caralluma europaea (Guss.) N.E.Br (Apocynaceae) from Lampedusa Island were analyzed by a headspace GC method. The analyses allowed the identification and quantification of 41 compounds. The main components were, among the monoterpenoids, terpinolene (23.3%), α-terpinene (19.1%) and linalool (18.4%), whereas, among the carbonylic compounds the major constituents were heptanal (2.0%), octanoic acid (2.4%) and hexanoic acid (1.7%). The presence of a nitrogen containing compound, indole (0.8%) and of a sulphur containing compound, dimethylsulphide (t), noteworthy. The compounds found in the flowers of C. europaea have been compared with data available in the literature as regard to their odor, presence in other sapromyiophilous taxa, possible role as semiochemicals, and presence in decaying organic matter. 89.3% of total constituents have been described in other sapromyiophilous taxa. Some of the compounds are present in several types of decaying organic matter (excrements, decomposing bodies, and spoiled fish, etc). Several volatiles found in C. europaea flowers are used as semiochemicals by Hymenoptera, Coleoptera, Diptera, Lepidoptera and other insects. Sixteen volatiles, accounting for 32.4% of the total constituents, are described as attractants of some Diptera families, with a biology linked to decaying organic matter. Our data thus confirm that C. europaea floral bouquet falls within the sapromyiophilous pollination syndrome.

Changes in the composition of volatile compounds of Spartium junceum induced by the phytoplasmal disease, Spartium witches’‐broom

Abstract In southern Italy, Spartium junceum (Spanish broom) is severely affected by a phytoplasmal disease, Spartium witches’‐broom (SpaWB). The volatile fractions extracted from flowers of healthy and diseased plants, examined by gas chromatography and gas chromatography–mass spectrometry, appeared to be quantitatively and qualitatively different. In both the healthy and the diseased plants, the main components were n‐alkanes, which occurred at a rate of 55.2% and 38.8%, respectively. The level of aliphatic acids was considerably lower in flowers of the diseased plants than in those of the healthy plants (4.5% vs. 18.7%). Sesquiterpenes were detected only in the diseased plants. It is possible that the changes in the composition of secondary metabolites of diseased plants can be related to plant defense responses. Abbreviations: AP, apple proliferation; EY, elm yellows; SpaWB, Spartium witches’‐broom

Volatile constituents of aerial parts of Lasiopogon muscoides

Lasiopogon muscoides (Desf.) DC. (syn. Gnaphalium muscoides Desf.) is a member of the subtribe Gnaphaliinae, family Asteraceae. This plant is a rare annual herb, 1–5 cm high with thin prostate branching, densely gray and white woolly. Leaves are small, linear, or narrowly spathulate, obtuse, sessile, entire, dense woolly. Capitula terminal, glomerate, are surrounded by closely touching floral leaves, equalling capitula, white woolly [1]. Gnaphalium species are known in traditional medicine, above all in the Chinese tradition, for their different biological activities: antitussive, expectorant, antiasthmatic, anti-inflammatory, immunomodulating, antimicrobial, antidiabetic, and cytotoxic [2–6]. The genus is characterized by the presence of diterpenes [6, 7], some of which showed cytotoxicity against human epithelioid cervical carcinoma cells [6], flavonoids [8–12], and caffeoylquinic acid derivatives [10]. Phenolic compounds showed antifeedant [8, 9], anti-inflammatory [10], and anti-diabetic activities [12]. Also volatile oils characterize the genus Gnaphalium [13–16], but there are no exhaustive studies on their composition. A literature search revealed no references to previous work on the essential oil of L. muscoides. The hydrodistillation of the aerial parts of L. muscoides yielded 0.21% (w/w) of essential oil characterized by a pale yellow color [17]. GC and GC/MS analysis enabled the identification of a total of 51 constituents, representing 92.4% of the oil [18]. The relative concentrations of the volatile components identified are presented in Table 1 according to their elution order (LRI) on an HP-5 column. The components may be grouped in to five main classes: fatty acids (31.3%), sesquiterpenoids (29.7%), carbonylic compounds (22.7%), hydrocarbons (4.8%), and phenols (3.0%). Hexadecanoic acid (13.7%), (Z,Z,Z)-9,12,15-octadecatrienoic acid (7.8%), and tetradecanal (7.3%) were recognized as the main constituents. Fatty acids and esters (31.3%), in the main, were the most abundant components, together with sesquiterpenoids (29.7%). In the first fraction hexadecanoic acid (13.7%) and (Z,Z,Z)-9,12,15-octadecatrienoic acid (7.8%) clearly prevailed, but there was also a good quantity of (Z,Z)-9,12-octadecadienoic acid (4.3%). As regards sesquiterpenoids, sesquiterpene hydrocarbons (17.4%) and oxygen-containing sesquiterpenes (12.3%) were present in a quite similar percentage. γ-Cadinene (3.9%), caryophyllene (3.2%), and epi-bicyclosesquiphellandrene (2.3%) prevailed in the first fraction, while in the second caryophyllene oxide (4.9%) was the most abundant. Carbonylic compounds (22.7%) were also present in quite high amounts; tetradecanal (7.3%) and tridecanal (5.8%) were the main substances in this fraction. As regards essential oil from other Gnaphalium species, also the essential oil from G. citrinum (vira-vira) seems to be rich in palmitic acid [14]. The MIC and MBC values of the essential oils tested against ten selected microorganisms, both Gram+ and Gram–, showed no action against all the pathogens (MIC and MBC 100 μg/mL or >100 μg/mL). Only Staphylococcus epidermidis was a little affected by the oil (MIC 50 μg/mL, MBC 100 μg/mL). Plant Material. Aerial parts of Lasiopogon muscoides (Desf.) DC. were collected at Brac (Croatia), 450 ms/l, in August 2007 (a voucher specimen was deposited in the Herbarium of the Department of Botany, Palermo University, Palermo, Italy (PAL 06/185).

Essential oil from aerial parts of Vernonia colorata Drake and Vernonia nigritiana Oliver et Hiern. (Asteraceae) growing wild in Mali

Abstract The essential oils from the aerial parts of Vernonia colorata (Willd.) Drake and Vernonia nigritiana Oliver et Hiern. (Asteraceae) grown wild in Mali were obtained by hydrodistillation. 115 components have been identified in the oils that have shown a different composition, both qualitative and quantitative.