Chemical variability ofJuniperus oxycedrus ssp.oxycedrus berry and leaf oils from Corsica, analysed by combination of GC, GC–MS and13C-NMR

The Leaf Essential Oil of Gynoxys buxifolia (Kunth) Cass. (Asteraceae): A Good Source of Furanoeremophilane and Bakkenolide A

The present study describes the chemical and enantiomeric composition of a new essential oil, distilled from the dry leaves of Gynoxys buxifolia (Kunth) Cass. The chemical analysis was conducted by GC-MS and GC-FID, on two orthogonal capillary columns. A total of 72 compounds were detected and quantified with at least one column, corresponding to about 85% by weight of the whole oil mass. Of the 72 components, 70 were identified by comparing the respective linear retention indices and mass spectra with data from the literature, whereas the two main constituents were identified by preparative purification and NMR experiments. The quantitative analysis was carried out calculating the relative response factor of each compound according to their combustion enthalpy. The major constituents of the EO (≥3%) were: furanoeremophilane (31.3-28.3%), bakkenolide A (17.6-16.3%), caryophyllene oxide (6.0-5.8%), and (E)-β-caryophyllene (4.4%). Additionally, the hydrolate was also analyzed with respect to the dissolved organic phase. About 40.7-43.4 mg/100 mL of organic compounds was detected in solution, of which p-vinylguaiacol was the main component (25.4-29.9 mg/100 mL). Finally, the enantioselective analysis of some chiral terpenes was carried out, with a capillary column based on β-cyclodextrin chiral stationary phase. In this analysis, (1S,5S)-(-)-α-pinene, (1S,5S)-(-)-β-pinene, (S)-(+)-α-phellandrene, (S)-(+)-β-phellandrene, and (S)-(-)-terpinen-4-ol were detected as enantiomerically pure, whereas (S)-(-)-sabinene showed an enantiomeric excess of 69.2%. The essential oil described in the present study is a good source of two uncommon volatile compounds: furanoeremophilane and bakkenolide A. The former lacks bioactivity information and deserves further investigation, whereas the latter is a promising selective anticancer product.

Data handling and data analysis in metabolomic studies of essential oils using GC-MS

Gas chromatography electron impact ionization mass spectrometry (GC-EI-MS) has been, and remains, the most widely applied analytical technique for metabolomic studies of essential oils. GC-EI-MS analysis of complex samples, such as essential oils, creates a large volume of data. Creating predictive models for such samples and observing patterns within complex data sets presents a significant challenge and requires application of robust data handling and data analysis methods. Accordingly, a wide variety of software and algorithms has been investigated and developed for this purpose over the years. This review provides an overview and summary of that research effort, and attempts to classify and compare different data handling and data analysis procedures that have been reported to-date in the metabolomic study of essential oils using GC-EI-MS.

Isolation of eudesmane type sesquiterpene ketone from Prangos heyniae H.Duman & M.F.Watson essential oil and mosquitocidal activity of the essential oils

In the present work, an endemic species Prangos heyniae collected in four locations from Turkey was subjected to hydrodistillation in Clevenger type apparatus to obtain the essential oils (EO1-4). The gas-chromatography/mass spectrometry (GC/MS) and gas-chromatography-flame ionization detector (GC/FID) analyses showed that the EOs were rich in sesquiterpenes, germacrene D (10.3-12.1%), β-bisabolene (14.4%), kessane (26.9%), germacrene B (8.2%), elemol (3.4-46.9%), β-bisabolenal (1.4-70.7%), β-bisabolenol (8.4%) and an eudesmane type sesquiterpene (1) (16.1%) with [M+218]. This unidentified compound (1) was isolated in a rapid one-step manner with >95.0% purity using Preparative Capillary Gas Chromatography (PCGC) with an HP Innowax column connected to a Preparative Fraction Collector (PFC) system. Structure determination was accomplished from 1D- and 2D-NMR spectroscopic data which determined a new eudesmane type sesquiterpene, 3,7(11)-eudesmadien-2-one (1). Using a biting deterrent bioassay, the mean proportion not biting (PNB) values of the P. heyniae EO1-4 were 0.88 for EO1 and 0.80 for EO2 which were similar to the positive control DEET (N,N-diethyl-3-methylbenzamide). The EO3 and EO4 had lower PNB values of 0.64 and 0.44, respectively. P. heyniae EO1-4 showed good larvicidal activity at 125 and 62.5 ppm whereas EO1-3 were slightly less effective at the dose of 31.25 ppm and EO4 was not active at 31.25 ppm against 1st instar Aedes aegypti.

In vitro susceptibility of Trypanosoma brucei brucei to selected essential oils and their major components

Aiming for discovering effective and harmless antitrypanosomal agents, 17 essential oils and nine major components were screened for their effects on T. b. brucei. The essential oils were obtained by hydrodistillation from fresh plant material and analyzed by GC and GC-MS. The trypanocidal activity was assessed using blood stream trypomastigotes cultures of T. b. brucei and the colorimetric resazurin method. The MTT test was used to assess the cytotoxicity of essential oils on macrophage cells and Selectivity Indexes were calculated. Of the 17 essential oils screened three showed high trypanocidal activity (IC₅₀ < 10 μg/mL): Juniperus oxycedrus (IC₅₀ of 0.9 μg/mL), Cymbopogon citratus (IC₅₀ of 3.2 μg/mL) and Lavandula luisieri (IC₅₀ of 5.7 μg/mL). These oils had no cytotoxic effects on macrophage cells showing the highest values of Selectivity Index (63.4, 9.0 and 11.8, respectively). The oils of Distichoselinum tenuifolium, Lavandula viridis, Origanum virens, Seseli tortuosom, Syzygium aromaticum, and Thymbra capitata also exhibited activity (IC₅₀ of 10-25 μg/mL) but showed cytotoxicity on macrophages. Of the nine compounds tested, α-pinene (IC₅₀ of 2.9 μg/mL) and citral (IC₅₀ of 18.9 μg/mL) exhibited the highest anti-trypanosomal activities. Citral is likely the active component of C. citratus and α-pinene is responsible for the antitrypanosomal effects of J. oxycedrus. The present work leads us to propose the J. oxycedrus, C. citratus and L. luisieri oils as valuable sources of new molecules for African Sleeping Sickness treatment.

Chemical Composition and Variability of Leaf and Berry oils from Corsican Juniperus macrocarpa

The chemical composition of five leaf oil samples and eighteen berry oil samples from Corsican Juniperus macrocarpa have been investigated by GC(RI), GC-MS and 13C NMR. The composition of berry oils was dominated by monoterpene hydrocarbons with α-pinene (56.4-78.9%) as main component followed by myrcene (2.2-11.9%). Germacrene D (4.5-103%) was the major sesquiterpene. The contents of the main components of leaf oils varied drastically from sample to sample: α-pinene (28.7-76.4%), δ3-carene (up to 17.3%), β-phellandrene (up to 12.3%), manoyl oxide (up to 8.1%). The occurrence of the unusual ( Z)-pentadec-6-en-2-one (0.1-1.2%) should be pointed out. Statistical analysis (Principal Component Analysis and k- means partition) suggested a unique group with atypical samples.

Toxicity of Juniperus oxycedrus oil constituents and related compounds and the efficacy of oil spray formulations to Dermatophagoides farinae (Acari: Pyroglyphidae)

The American house dust mite (AHDM), Dermatophagoides farinae Hughes (Acari: Pyroglyphidae), is recognized as an important source of allergens in the domestic environment. This study was conducted to determine whether 19 constituents from essential oil of cade, Juniperus oxycedrus L. (Cupressaceae), eight structurally related compounds, and another 16 previously known cade oil constituents were toxic for adult AHDMs and to determine the route of acaricidal action of the test compounds, as well as to assess the control efficacy of four experimental spray formulations containing the oil (10-40 mg/L sprays). In a fabric-circle contact mortality bioassay, methyleugenol (LD₅₀, 5.82 µg/cm²) and guaiacol (8.24 µg/cm²) were the most toxic compounds against the mites, and the toxicity of these compounds and benzyl benzoate did not significantly differ. High toxicity was also observed with eugenol, m-cresol, and nerolidol (LD₅₀, 12.52-19.52 µg/cm²), and these compounds were significantly more toxic than N,N-diethyl-3-methylbenzamide (DEET) (LD₅₀, 37.67 µg/cm²). Cade applied as 30 or 40 mg/L experimental sprays provided 96 and 100% mortality against the mites, respectively, whereas permethrin (cis:trans, 25:75) 2.5 g/L spray treatment resulted in 17% mortality. In vapor-phase mortality tests, the compounds described were consistently more toxic in closed versus open containers, indicating that toxicity was achieved mainly through the action of vapor. Reasonable mite control in indoor environments can be achieved by spray formulation containing the 40 mg/L cade oil as potential contact-action fumigants.

Chemical composition and antimicrobial activity of berry essential oil of Juniperus oxycedrus L. (Cupressaceae) grown wild in Republic of Macedonia

Chemical composition and antimicrobial activity of essential oil isolated from berries from 2 different samples of Juniperus oxycedrus L. (Cupressaceae), growing wild in Republic of Macedonia was investigated. Performing GC/FID/MS analysis, one hundred components were identified, representing 96.0-98.95% of the oil. The major components were α-pinene (22.54- 27.12%), myrcene (11.26- 15.13%) and limonene (2.78-18.06%). Antimicrobial screening of the J. oxycedrus essential oils was made by disc diffusion and broth dilution method against 16 bacterial isolates of Gram positive and Gram negative bacteria and one strain of Candida albicans. The most sensitive bacteria was Haemophilus influenzae (MIC = 125 ml/ml). The essential oils showed moderate antimicrobial activity against Streptococcus pneumoniae, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyogenes, Corynebacterium spp., Escherichia coli and Campilobacter jejuni (MIC > 500 ml/ml) and no activity against Candida albicans, Staphylococcus epidermidis, Acinetobacter spp., Salmonella enteritidis, Shigella flexnery, Klebsiella pneumonia, Pseudomonas aeruginosa, Enterococcus and Proteus mirabilis.

Chemical and Antibacterial Polymorphism ofJuniperus oxycedrusssp.oxycedrusandJuniperus oxycedrusssp.macrocarpa(Cupressaceae) Leaf Essential Oils from Tunisia

Essential oils fromJuniperus oxycedrusL. have been used since antiquity for fragrance, flavoring, medicinal, antimicrobial, insecticidal, and cosmetic purposes. Several works studied the chemical composition of the essential oils ofJuniperus oxycedrusleaves. The aim of this study is to investigate the chemotaxonomic relationships and antibacterial activity of two Tunisian subspecies:Juniperus oxycedrusssp.oxycedrus(L. K.) Deb. andJuniperus oxycedrusssp.macrocarpa(S. & m.) Ball. In addition, and for the first time, we reported the antibacterial activities of TunisianJ. oxycedrusssp.macrocarpaandJ. oxycedrusssp.oxycedrusagainst four bacteria. Essential oils obtained by hydrodistillation were analysed by GC and GC/MS. Fifty-five constituents were identified. Thirty four major compounds were retained for the study of the chemical variability, andα-pinene, sylvestrene,p-cymene, and 13-epi-manoyl oxide were the main ones. The chemical principal components analysis (PCA) identified three chemotypes. The study of the antibacterial activity showed thatEscherichia coliwas found to be extremely resistant (zone diameter 0 mm) to all the oils tested, whileStaphylococcus aureuswas the most sensitive strain (zone diameter 13.5 mm and MIC ranged from 600 to 650 μg/mL).

Fatty Acid Composition of Juniperus Species (Juniperus Section) Native to Turkey

Fatty acid compositions of seeds of five taxa of the Juniperus section of the genus Juniperus L. (Cupressaceae), i. e. J. drupacea Lab., J. communis L. var. communis, J. communis var. saxatilis Pall., J. oxycedrus L. subsp. oxycedrus, and J. oxycedrus subsp. macrocarpa (Sibth. & Sm.) Ball, were investigated. Methyl ester derivatized fatty acids of the lipophylic extracts of the five species were comparatively analyzed by capillary gas chromatography-mass spectrometry (GC-MS). Juniperus taxa showed uniform fatty acid patterns, among which linoleic (25.8–32.5%), pinolenic (11.9–24.1%) and oleic acids (12.4–17.2%) were determined to be the main fractions in the seed oils. Juniperonic acid was found to be remarkably high in J. communis var. saxatilis (11.4 %), J. oxycedrus subsp. oxycedrus (10.4 %), and J. communis var. communis (10.1 %). To the best of our knowledge, the present work discloses the first report on the fatty acid compositions of seeds of this Juniperus section grown in Turkey.

Leaf essential oil of Juniperus oxycedrus L. (Cupressaceae) harvested in northern Tunisia: composition and intra-specific variability

The essential oil composition of leaves of 60 individual trees of Juniperus oxycedrus L. growing in four locations in Tunisia harvested in three different seasons were investigated by GC and GC/MS. Seventy compounds were identified in the oils, and a relatively high variation in their contents were found. All the oils were dominated by terpenic hydrocarbons, with alpha-pinene (27.35-58.03%) as the main component, followed by geranyl acetone (13; 1.96-7.14%), 13-epimanoyl oxide (16; 1.35-6.95%), and eudesma-4(15),7-dien-1-ol (11; 1.39-4.18%). The 18 major oil components were processed by hierarchical clustering and principal component analysis (PCA) allowing to establish four groups, one divided into two subgroups, of populations according to the location and season of harvest. Their oils were differentiated by one compound or more, showing a clear seasonal and geographical polymorphism in their chemical composition allowing the identification of specific chemotypes. The pattern of geographic variation in the essential oil composition indicated that the oils of the populations from the continental site (Makthar) were clearly distinguished from those of the littoral localities (Tabarka, Hawaria, and Rimel).

A comparative study on the antinociceptive and anti-inflammatory activities of five Juniperus taxa

ETHNOPHARMACOLOGICAL RELEVANCE

Juniperus L. (Cupressaceae) species have been used to various inflammatory and infectious diseases such as bronchitis, colds, cough, fungal infections, hemorrhoids, gynecological diseases, and wounds in Turkish folk medicine.

AIM OF THE STUDY

To evaluate this traditional information, anti-inflammatory and antinociceptive activities of the methanolic and aqueous extracts prepared from different parts (stem, fruit and leaves) of the five Turkish taxa under Juniperus section of the gender; J. drupacea, J. communis var. communis, J. communis var. saxatilis, J. oxycedrus subsp. oxycedrus, and J. oxycedrus subsp. macrocarpa growing were investigated.

METHODS

For the anti-inflammatory activity, carrageenan-induced and PGE(2)-induced hind paw edema models, and for the antinociceptive activity p-benzoquinone-induced writhing and hot plate tests in mice were employed.

RESULTS

The methanolic extracts of fruit and leaves from J. oxycedrus subsp. oxycedrus and J. communis var. saxatilis exhibited notable inhibition in carrageenan-induced edema model at a dose of 100mg/kg. The same extracts also displayed significant activity against PGE(2)-induced edema model. While, the remaining extracts were found inactive against these edema models. A similar activity pattern was observed against p-benzoquinone-induced abdominal constriction test without inducing any gastric damage or apparent acute toxicity, whereas all extracts were inactive in hot plate test.

CONCLUSION

The experimental data demonstrated that J. oxycedrus subsp. oxycedrus and J. communis var. saxatilis displayed remarkable anti-inflammatory and antinociceptive activities; however, further studies are warranted to define and isolate the active anti-inflammatory and antinociceptive components from these active species which may yield safe and effective agents to be used in the treatment of inflammatory disorders.