Sesquiterpene-rich volatile constituents of Ipomoea obscura (L.) Ker-Gawl.

The hydro-distilled essential oil from flowering aerial parts of Ipomoea obscura (L.) Ker-Gawl. (Convolvulaceae) was investigated by using gas chromatography equipped with a flame ionisation detector GC-FID and gas chromatography coupled with a mass spectrometry (GC/MS). Forty-two components, representing 97.1% of the total oil, were identified. The major constituents of the essential oil were α-bulnesene (23.8%), α-humulene (13.7%) and seychellene (11.2%). The other minor constituents were α-guaiene (8.3%), β-caryophyllene (7.1%), γ-terpinene (4.2%), hexadecanoic acid (3.0%) and β-elemene (2.7%). The oil was found to be rich in sesquiterpene hydrocarbon type constituents (78.4%).     

Chemical composition of the essential oil from Pulicaria vulgaris var. graeca (Sch.-Bip.) Fiori (Asteraceae) growing wild in Sicily and its antimicrobial activity

In this study the chemical composition of the essential oil from aerial parts of Pulicaria vulgaris var. graeca (Sch.-Bip.) Fiori collected in Sicily was evaluated by GC and GC–MS. The main components of P. vulgaris var. graeca oil were hexadecanoic acid (21.7%), β-caryophyllene (14.3%) and geranyl propionate (8.2%). The comparison with other studied oils of genus Pulicaria is discussed. Antibacterial activity against several bacteria, including some ones infesting historical art craft, was also determined.     

Identification of essential oil components of Marrubium thessalum Boiss. & Heldr., growing wild in Greece

The essential oil of the Greek endemic species Marrubium thessalum Boiss. & Heldr. (Lamiaceae) was obtained by the hydrodistillation of its aerial parts during the flowering stage. The composition of the oil was analysed by GC and GC-MS. Thirty compounds were identified. The oil was devoid of monoterpenes, while sesquiterpenes constituted the major fraction. The main components of the oil were caryophyllene oxide (21.7%), β-caryophyllene (17.6%), germacrene D (15.3%), β-bisabolene (12.6%) and trans-β-farnesene (8.1%).     

Analysis of essential oils from Scutellaria orientalis ssp. alpina and S. utriculata by GC and GC-MS

The chemical composition of the essential oils obtained from aerial parts of Scutellaria orientalis L. ssp. alpina (Boiss.) O. Schwarz and S. utriculata Labill. growing wild in Lebanon, were analyzed by GC and GC-MS. In S. orientalis ssp. alpina, strongly characterized by sesquiterpenes (41.2%) and particularly sesquiterpene hydrocarbons (31.7%), hexahydrofarnesylacetone (11.7%) was recognized as the main constituent, together with hexadecanoic acid (7.6%), caryophyllene (7.4%), caryophyllene oxide (6.8%), 4-vinylguaiacol (5.4%) and germacrene D (5.4%). S. utriculata oil was instead constituted above all by monoterpenes (42.2%), particularly oxygen containing monoterpenes (39.9%), and in this oil the main compounds were linalool (20.1%), 4-vinyl guaiacol (15.5%), alpha-terpineol (8.9%), (E)-nerolidol (8.9%) and geraniol (8.2%).     

Volatile oils from the plant and hairy root cultures of Ageratum conyzoides L

Two lines of hairy root culture of Ageratum conyzoides L. induced by Agrobacterium rhizogenes ATCC 15834 were established under either complete darkness or 16 h light/8 h dark photoperiod conditions. The volatile oil yields from aerial parts and roots of the parent plant, the hairy root culture photoperiod line and the hairy root culture dark line were 0.2%, 0.08%, 0.03% and 0.02%, (w/w), respectively. The compositions of the volatiles from the hairy roots, plant roots and aerial parts were analysed by GC and GC-MS. The main components of the volatiles from the hairy root cultures were β-farnesene, precocene I and β-caryophyllene, in different amounts, depending on light conditions and also on the age of cultures. Precocene I, β-farnesene, precocene II and β-caryophyllene were the main constituents of the volatile oils from the parent plant roots, whereas precocene I, germacrene D, β-caryophyllene and precocene II were the main constituents of the aerial parts of the parent plant. Growth and time-course studies of volatile constituents of the two hairy root lines were compared. Qualitative and quantitative differences were found between the volatile oils from the roots of the parent plant and those from the hairy roots.     

Variability of essential oils of Betonica officinalis (Lamiaceae) from different wild populations in Kosovo

The aerial parts and roots of Betonica officinalis were collected from three localities characterized by different ecological conditions to study the natural variability of the chemical composition of the essential oils in this plant. The leaves and inflorescences were collected during the flowering time, whereas the roots were collected at the end of the vegetative period. The plant material was dried at room temperature. The essential oils were obtained by micro-steam hydrodistillation and analyzed using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Overall, 69 constituents were identified in all localities and plant parts. The main compositions of the leaves in all localities were alpha-pinene, 1-octen-3-ol, beta-bourbonene, (E)-caryophyllene and germacrene D. The essential oil of the inflorescences was characterized by these main constituents: alpha-pinene, (E)-caryophyllene and trans-beta-farnesene. In all localities, the percentages of alpha-pinene and (E)-caryophyllene were higher in the inflorescences than in the leaves, whereas nonane was the main constituent in the roots.     

Chemical composition and insecticidal activity against Sitophilus zeamais of the essential oils derived from Artemisia giraldii and Artemisia subdigitata

The aim of this research was to determine the chemical composition and insecticidal activity of the essential oils derived from flowering aerial parts of Artemisia giraldii Pamp. and A. subdigitata Mattf. (Family: Asteraceae) against the maize weevil (Sitophilus zeamais Motsch.). Essential oils of aerial parts of A. giraldii and A. subdigitata were obtained from hydrodistillation and investigated by GC and GC-MS. A total of 48 and 33 components of the essential oils of A. giraldii and A. subdigitata were identified, respectively. The principal compounds in A. giraldii essential oil were β-pinene (13.18%), iso-elemicin (10.08%), germacrene D (5.68%), 4-terpineol (5.43%) and (Z)-β-ocimene (5.06%). 1,8-Cineole (12.26%) and α-curcumene (10.77%) were the two main components of the essential oil of A. subdigitata, followed by β-pinene (7.38%), borneol (6.23%) and eugenol (5.87%). The essential oils of A. giraldii and A. subdigitata possessed fumigant toxicity against the maize weevils with LC50 values of 6.29 and 17.01 mg/L air, respectively. The two essential oils of A. giraldii and A. subdigitata also exhibited contact toxicity against S. zeamais adults with LD50 values of 40.51 and 76.34 μg/adult, respectively. The results indicated that the two essential oils show potential in terms of fumigant and contact toxicity against grain storage insects.     

Chemical composition of the essential oil of Moluccella spinosa L. (Lamiaceae) collected wild in Sicily and its activity on microorganisms affecting historical textiles

In this study the chemical composition of the essential oil from aerial parts of Moluccella spinosa L. collected in Sicily was evaluated by GC and GC-MS. The main components of M. spinosa L. were α-pinene (26.6%), caryophyllene oxide (16.8%) and β-caryophyllene (8.6%). A comparison with other studied oils of genus Moluccella is made. Antibacterial and antifungal activities against some microorganisms infesting historical textiles were also determined.     

Chemical composition of the essential oils from the flower, leaf and stem of Lonicera japonica

The essential oils from different aerial parts of Lonicera japonica have been extracted by hydro-distillation and analyzed by gas chromatography and gas chromatography coupled with mass spectrometry. Quantitative and qualitative differences were found between the analyzed plant parts. A total of eighty-nine compounds were identified. The main constituents were (Z,Z)-farnesole (16.2%) and linalool (11.0%) for the flowers fraction, hexadecanoic acid (16.0%) and linalool (8.7%) for the leaves fraction, and hexadecanoic acid (31.4%) for the stems. Monoterpene hydrocarbons were absent from all the oils, and oxygenated sesquiterpenes were not identified in the essential oil of the stem.     

Comparative volatile oil composition of four Ocimum species from northern India

The hydrodistilled essential oils of Ocimum basilicum L. cvs. 'Vikarsudha' and 'CIM-Soumya', Ocimum sanctum L. cvs. 'Green' (CIM-Ayu) and 'Purple', Ocimum gratissimum L. and Ocimum kilimandscharicum Guerke have been studied by capillary gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Phenylpropanoids (65.2-77.6%) constituted the major proportion of the essential oil compositions of O. sanctum, O. basilicum and O. gratissimum, whilst oxygenated monoterpenes (72.7%) constituted the major proportion of the oil composition of O. kilimandscharicum. The essential oil compositions of cvs. 'Green' and 'Purple' of O. sanctum were almost the same, and both cultivars were dominated by eugenol (67.4% and 72.8%), β-elemene (11.0% and 10.9%), β-caryophyllene (7.3% and 8.4%) and germacrene D (2.4% and 2.2%), whilst the major components in O. basilicum cvs. 'Vikarsudha' and 'CIM-Soumya' were methyl chavicol (68.0% and 64.9%) and linalool (21.9% and 25.6%), along with bicyclogermacrene (2.0% and 0.7%) and α-terpineol (1.2% and 0.1%). Eugenol (77.2%), 1,8-cineole (7.6%), germacrene D (2.7%) and β-caryophyllene (1.7%) were identified as the major constituents of O. gratissimum. On the contrary, the essential oil from O. kilimandscharicum was mainly dominated by monoterpenoids (95.8%), represented by camphor (64.9%), limonene (8.7%), camphene (6.4%) and (E)-β-ocimene (3.0%).     

The essential oils of the aerial parts of two Hypericum taxa (Hypericum triquetrifolium and Hypericum aviculariifolium subsp. depilatum var. depilatum (Clusiaceae)) from Turkey

In this study, essential oil compositions of two Hypericum L. taxa (Hypericum triquetrifolium Turra. and Hypericum aviculariifolium Jaub. et Spach subsp. depilatum var. depilatum (Freyn et Bornm.) Robson) naturally grown in Turkey were determined using gas chromatography and gas chromatography-mass spectrometry systems. The essential oils were obtained by hydrodistillation from the aerial parts of plants. A total of 45 compounds were identified in the essential oils of H. triquetrifolium; 1-hexanal (18.8%), 3-methylnonane (12.5%) and α-pinene (12.3%). In this study, 41 components were identified in H. aviculariifolium subsp. depilatum var. depilatum oil; α-pinene (52.1%), germacrene D (8.5%) and β-pinene (3.6%) were the predominant constituents. The essential oil analysis showed that monoterpene concentrations were higher than that of the sesquiterpenes in both oils. The results were discussed in the meaning of the usefulness of these plants and their chemicals as natural products and potential usage in chemotaxonomy.     

A study on the seasonal variation of the essential oil composition from Plectranthus hadiensis and its antibacterial activity

The chemical composition and seasonal variation of the essential oil from the aerial parts of Plectranthus hadiensis grown during the rainy and summer seasons in the Western Ghats of India was analysed by GC–MS technique. The analysis of rainy season oil led to the identification of 31 compounds, representing 96.4% of the essential oil and the winter season oil led to 25 compounds, representing 95.1% of the oil. Most of the compounds were sesquiterpenes and oxygenated monoterpenes. The major components of the rainy season oil were L-fenchone (30.42%), β-farnesene (11.87%), copaene(11.10%), 2,3-dimethyl hydroquinone (10.78%), α-caryophyllene(8.41%) and piperitone oxide (3.94%) and of the summer season oil are L-fenchone (31.55%), copaene(11.93%), β-farnesene (10.45%), 1,8-naphthalenedione, 8a-ethylperhydro (10.06%), α-caryophyllene(6.36%), piperitone oxide (5.79%) and limonene(4.63%). Antibacterial activity of the essential oil of P. hadiensis was tested using zone of inhibition and minimum inhibition concentration methods. Both the oils inhibited the organisms and showed the zone of inhibition in the range of 20–35 mm with MIC values between 32 and 64 mg/dL.     

Chemical composition of the essential oil of Jacobaea maritima (L.) Pelser & Meijden and Jacobaea maritima subsp. bicolor (Willd.) B. Nord. & Greuter (Asteraceae) collected wild in Croatia and Sicily,respectively

In this study, the chemical compositions of the essential oils from aerial parts (JmA) and radices (JmR) of Jacobaea maritima (L.) Pelser & Meijden, collected in Croatia, and of Jacobaea maritima subsp. bicolor (Willd.) B. Nord. & Greuter, collected in Sicily, were evaluated by using gas chromatography and gas chromatography–mass spectrometry. The main components of the essential oil from J. maritima, both in JmA and JmR, were pentacosane (15.7%), heptacosane (13.1%) and nonacosane (8.1%) whereas the essential oil from J. maritima subsp. bicolor was characterised by the presence of hexadecanoic acid (14.6%), caryophyllene oxide (9.3%) and hexahydrofarnesylacetone (6.5%). The comparison of the essential oil with other studied oils of the genus Jacobaea is discussed.     

Volatile constituents of Amomum maximum Roxb and Amomum microcarpum C. F. Liang & D. Fang: two Zingiberaceae grown in Vietnam

The chemical composition of essential oils obtained from the hydrodistillation of different parts of Amomum maximum Roxb and Amomum muricarpum C. F. Liang & D. Fang (Zingiberaceae) grown in Vietnam are reported. The analysis was performed by means of gas chromatography–flame ionisation detectoorand gas chromatography coupled with mass spectrometry. The major compounds identified in the oils of A. maximum were β-pinene (20.4–40.8%), α-pinene (6.8–15.0%), β-elemene (2.5–12.8%) and β-caryophyllene (2.3–10.3%). Moreover, β-phellandrene (11.6%) was present in the root oil. The main compound identified in all the oil samples of A. muricarpum was α-pinene (24.1–54.7%) and β-pinene (9.2–25.9%). In addition, limonene (7.4%) and δ-3-carene (9.4%) were present in the leaves and stem oils, respectively. However, while β-phellandrene (8.3%) could be seen prominent in the root oil, the fruits contained significant amount of zingiberene (6.3%). The largest amount of τ-muurolol (13.0%) was found in the flower oil.     

Senna occidentalis (L.) Link and Senna hirsuta (L.) H. S. Irwin & Barneby: constituents of fruit essential oils and antimicrobial activity

Senna occidentalis and S. hirsuta are mostly gathered from the wild for medicinal use and have a disagreeable odour when crushed. The volatile oils isolated from fresh fruits of S. occidentalis and S. hirsuta were subjected to gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) and antimicrobial assays. GC and GC-MS analyses permitted the identification of 58 constituents. S. occidentalis oil was dominated by cyperene (10.8%), β-caryophyllene (10.4%), limonene (8.0%) and caryophyllene oxide (6.8%). The main components of S. hirsuta fruit oil were benzyl benzoate (24.7%), τ-cadinol (18.9%), 2,5-dimethoxy-p-cymene (14.6%) and β-caryophyllene (5.1%). S. occidentalis fruit oil exhibited better antimicrobial activity (MIC 78–312 μg/mL) against Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Aspergillus niger compared with S. hirsuta oil. The compositions and the activities of the fruit essential oils of S. occidentalis and S. hirsuta are reported for the first time.     

Chemical composition of the essential oil of Salvia microstegia Boiss. et Balansa growing wild in Lebanon

The essential oil of aerial parts of Salviamicrostegia Boiss. et Balansa (Lamiaceae) growing wild in Lebanon was obtained by hydrodistillation and was analysed by GC and GC-MS. 70 compounds, representing 94.0% of the oil, were identified. The major components were caryophyllene oxide (6.2%), pulegone (5.7%), 4-vinylguaiacole (5.3%), hexadecanoic acid (5.1%) and menthone (4.9%).     

Volatile components of Centaurea bracteata and C. pannonica subsp. pannonica growing wild in Croatia

This paper reports on the volatile components of oils from the aerial parts (CBA) and roots (CBR) of Centaurea bracteata Scop. and aerial parts of C. pannonica (Heuffel) Simonkai subsp. pannonica (CPA), two Asteraceae growing wild in Croatia. The volatile components, obtained by hydrodistillation, were determined by GC-MS analysis. The yields (w/w) of the dried oils were 0.10% (CBA), 0.22% (CBR) and 0.09% (CPA), respectively. A total of 91 compounds were identified accounting for 91.1%, 93.3% and 87.9% of the total oil for CBA, CBR and CPA, respectively. All the samples were characterized mainly by hydrocarbons (7.1-34.1%), fatty acids (9.7-45.9%), and oxygenated sesquiterpenes (15.2-16.6%). The major components of the samples were hexadecanoic acid (8.1-31.1%), nonacosane (0.6-13.4%) and caryophyllene oxide (4.5-11.9%). Monoterpenes, both hydrocarbons and oxygenated, were either absent or present in low amounts in all the oils. The similarity in the oil contents is consistent with the two species being placed in the same section, Jacea.     

Antiphytoviral activity of sesquiterpene-rich essential oils from four croatian teucrium species

The purpose of this study was to compare the essential oil profiles of four Croatian Teucrium species (Lamiaceae), as determined by GC and GC/MS, with their antiphytoviral efficiency. A phytochemical analysis showed that T. polium, T. flavum, T. montanum and T. chamaedrys are characterized by similar essential oil compositions. The investigated oils are characterized by a high proportion of the sesquiterpene hydrocarbons β-caryophyllene (7.1-52.0%) and germacrene D (8.7-17.0%). Other important components were β-pinene from T. montanum and α-pinene from T. flavum. The investigated essential oils were proved to reduce lesion number in the local host Chenopodium quinoa Willd. infected with Cucumber Mosaic Virus (CMV), with reductions of 41.4%, 22.9%, 44.3% and 25.7%, respectively.     

Determination of the chemical composition and antioxidant,anticancer, and antibacterial properties of essential oil of Pulicaria crispa from Saudi Arabia

Essential oils obtained from plants play critical roles in food and medicine. In this study, the phytochemical composition of Pulicaria crispa essential oil, and its antibacterial, antioxidant and anticancer properties were determined in vitro. The essential oil was extracted from the aerial parts of P. crispa through hydro-distillation using a Clevenger-type apparatus, and it was analyzed with GC-MS. The most dominant chemical constituents of the essential oil were sesquiterpenes (78.26%). The higher constituents were β-caryophyllene oxide (33.97%), modephene (23.34%), geranyl propionate (6.32%), geranyl isovalerate (6.74%), 4-cadinadiene (5%), humulene (4.05%), and β-caryophyllene (2.73%). The essential oil exhibited DPPH radical activity, and it exerted antibacterial effect against gram positive bacteria (Staphylococcus aureus and methicillin-resistant Staphylococcus aureus. However, it had no antibacterial effect on gram negative bacteria (Pseudomonas aeruginosa, Shigella sonnei, Klebsiella pneumoniae and Escherichia coli). The P. crispa essential oil produced significant cytotoxic effects against Hep-G2, MCF-7, Coca-2, and HT-29 ?cells. The oil was most toxic to Hep-G2 cells, based on its IC₂₀ and IC₅₀ values. These results indicate that the essential oil from P. crispa has potent biological properties which can be useful in the food and pharmaceutical industries.     

Chemical composition and antioxidant activity of essential oil from aerial parts of Teucrium flavum L. subsp. flavum growing spontaneously in Tunisia

The objectives of this study were to chemically characterise and evaluate the antioxidant potential of the essential oil from Teucrium flavum L. subsp. flavum growing spontaneously in Tunisia. The volatile oil was extracted by hydrodistillation of the aerial parts in a Clevenger type apparatus. Forty constituents were identified via GC and GC-MS analysis. β-caryophyllene (32.5%) and α-humulene (17.8%) were the most abundant components. The evaluation of free radical scavenging activity using stable DPPH free radical showed that the volatile oil exhibits a moderate antioxidant activity and reduces DPPH to 50% at EC₅₀ value of 1230 μg mL^? 1.