Essential oils composition of Eupatorium species growing wild in the Amazon

The essential oils of six Eupatorium species were obtained by hydrodistillation and analysed by GC-MS. The oil of E. macrophyllum was rich in sabinene (46.7%) and limonene (23.3%). The oil of E. laevigatum was mainly constituted by a mixture of aristolone+laevigatin (23.6%), globulol (16.2%) and germacrene D (8.6%). The principal constituents of the oils of the chemotypes A and B of E. squalidum, E. amygdalinum and E. conyzoides were caryophyllene oxide (17.4–30.1%), globulol (25.1%), germacrene D (10.4–21.6%), spathulenol (14.2%) and β-caryophyllene (7.1–12.3%). The oils of the chemotypes A and B of E. marginatum were dominated by α-zingiberene (57.5%), α-gurjunene (19.5%), germacrene D (14.8%), (E)-8-bisabolene (9.7%) and α-selinene (9.0%).     

The essential oil of Origanum vulgare L. ssp. vulgare growing wild in vilnius district (Lithuania)

The plants of wild Origanum vulgare L. ssp. vulgare were collected in 10 localities of Vilnius district (Lithuania) in 1995-1999. The main constituents of the essential oils from 8 localities were beta-ocimene (14.9-21.6%), germacrene D (10.0-16.2), beta-caryophyllene (10.8- 15.7%) and sabinene (6.6- 4.2%). The essential oils from two localities contained only three above compounds as major components: germacrene D, beta-ocimene and sabinene or beta-caryophyllene, beta-ocimene and germacrene D. Three chemotypes of essential oils were identified. The main chemotype was beta-ocimene germacrene D-beta-caryophyllene. The terpenic hydrocarbons made up 52.8-80.6% of the essential oils. The 42 identified components made up 85.6-98.0% of the essential oil.     

Volatile constituents of the leaves of Siparuna thecaphora (Siparunaceae) from Turrialba,Costa Rica

The composition of the essential oil from leaves of Siparuna thecaphora (Poepp. et Endl.) A. DC. collected in Turrialba, Costa Rica, was determined by capillary GC/MS. Seventy-six compounds were identified corresponding to ca. 95% of the oil. The major components were germacrene D (32.7%), alpha-pinene (16.3%), beta-pinene (13.8%) and beta-caryophyllene (4.1%). Thirty-one minor compounds were identified for the first time in this genus of plants.     

Essential oil composition of two endemic Centaurea species from Turkey, Centaurea mucronifera and Centaurea chrysantha, collected in the same habitat

The essential oils of two endemic Centaurea species from Turkey, C. mucronifera and C. chrysantha, collected in the same habitat, have been studied. The main compounds of the former were germacrene D (29.3%), β-eudesmol (17.4%) and β-caryophyllene (7.3%), while in the latter germacrene D (27.4%), caryophyllene oxide (9.5%) and bicyclogermacrene (5.4%) were detected among its major constituents. The two species produced many similar compounds in their essential oils that could be justified by the similar ecological conditions of their habitat, but also many differences were found that could confirm their taxonomic separation.     

Variability in essential oil composition of Piper dilatatum L.C. Rich

Twelve samples of air-dried aerial parts of Piper dilatatum L. C. Rich yielded essential oils and their volatile constituents were analyzed by GC and GC–MS. Sesquiterpenes, both hydrocarbons and oxygenated, were the most highly represented classes, the former ranging from 31.5% to 87.7% and the latter varying from 1.8% to 49.4%. Using hierarchical cluster analysis, the oils were divided into seven groups, whose main constituents were: (E)-caryophyllene, α-cadinol and germacrene D (group A); spathulenol, bicyclogermacrene and (Z)-β-ocimene, (group B); spathulenol, germacrene D and (E)-nerolidol, (group C); germacrene D, limonene, α-phellandrene and bicyclogermacrene (group D); β-elemene, germacrene D and β-pinene (group E); curzerene, p-cymene and α-eudesmol (group F); and (Z)-α-bisabolene, curzerene and germacrene D (group G). We have seen that Piper oils from the Amazon present as major constituents terpenoids and phenylpropanoids, always with the predominance of one over another. The essential oils of P. dilatatum presented in this paper, containing only mono- and sesquiterpenes as its major components, is further chemotaxonomic evidence of this dichotomy in the Piper genus.     

Evaluation of characteristic aroma compounds of Citrus natsudaidai Hayata (Natsudaidai) cold-pressed peel oil

The characteristic aroma compounds of Citrus natsudaidai Hayata essential oil were evaluated by a combination of instrumental and sensory methods. Sixty compounds were identified and quantified, accounting for 94.08% of the total peel oil constituents. Limonene was the most abundant compound (80.68%), followed by gamma-terpinene (5.30%), myrcene (2.25%) and alpha-pinene (1.30%). Nineteen compounds which could not be identified in the original oil were identified in the oxygenated fraction. Myrcene, linalool, alpha-pinene, beta-pinene, limonene, nonanal, gamma-terpinene, germacrene D, and perillyl alcohol were the active aroma components (FD-factor > 3(6)), whereas beta-copaene, cis-sabinene hydrate and 1-octanol were suggested as characteristic aroma compounds, having a Natsudaidai-like aroma in the GC effluent. Three other compounds, heptyl acetate, (E)-limonene oxide and 2,3-butanediol, which each showed a high RFA value (>35) were considered to be important in the reconstruction of the original Natsudaidai oil from pure odor chemicals. The results indicate that 1-octanol was the aroma impact compound of C. natsudaidai Hayata peel oil.     

Survival in different habitats: Extreme ultramafic and calcareous soils affect Stachys recta essential oils composition

Two populations of Stachys recta growing in Italy on ultramafic and calcareous soils have been studied for their essential oils. Although the yields were comparable, the composition of the essential oils differed significantly. Plants growing on ultramafic soil produced mainly non-terpene derivatives (55.7%), of which the most abundant ones were 1-octen-3-ol (38.2%) and (E)-3-hexen-1-ol (5.9%); the terpenes α-cadinol (6.1%) and δ-cadinene (5.6%) were also significantly represented. In contrast, the populations living on calcareous soil produced an essential oil dominated by terpenes (93.8%), with germacrene D (18.8%), β-caryophyllene (17.7%), 1,8-cineole (15.9%) and α-pinene (14.2%) among the main components.     

Variation of volatiles in Tunisian populations of Teucrium polium L. (Lamiaceae)

Volatiles from wild Tunisian diploid (2n=2x=26) and tetraploid (2n=4x=52) Teucrium polium L. populations from five bioclimatic zones were assessed by GC and GC/MS. Thirty-eight compounds were identified. Main volatiles at the species level were myrcene (6; 15.3%), germacrene D (27; 9.0%), alpha-pinene (6.6%), beta-pinene (3; 5.8%), and alpha-cadinol (38; 5.1%). A significant variation among populations was observed. The tetraploid populations belonging to the sub humid and lower semi arid bioclimates showed a high amount of myrcene (6; 24.2-43.8%), those from the upper arid contain high percentages of alpha-cadinol (38; 50.6%). The dominant compounds in diploid populations, mainly located in the semi arid zone, are alpha-pinene (1) and germacrene D (27). Population chemical structure, assessed by a principal component analysis (PCA) using all identified compounds, is concordant with bioclimate and ploidy level. In situ conservation of populations should be made appropriately according to these two factors.     

Composition of the volatile oils of two Anthemis L. taxa from Turkey

The essential oils of water-distilled aerial parts of Anthemis pseudocotula and Anthemis cretica subsp. pontica (Asteraceae) were analysed by GC-MS. As a result thirty-five and forty compounds were identified representing 93.1% and 89.0% of the oils, respectively. The main compounds of A. pseudocotula were 1,8-cineole (39.40%), camphor (9.36%), artemisiaketone (5.68%), filifolene (5.15%), and a-terpineol (4.69%), whereas beta-caryophyllene (20.26%), azulene (14.98%), spathulenol (6.03%), and germacrene D (5.82%) were the major constituents of A. cretica subsp. pontica.     

Insecticidal activity of essential oils from eleven Eucalyptus spp. and two hybrids: lethal and sublethal effects of their major components on Blattella germanica

The aim of the current study was to evaluate the fumigant activity of the essential oils from 11 species of the genus Eucalyptus and two of their hybrids on first instar of Blattella germanica L. The fumigant activity and repellence of the four major monoterpene components of these essential oils also were tested. Fumigant activity was evaluated by exposing nymphs to the vapors emitted by 50 microl of essential oil or monoterpene in a closed container. The lowest knockdown time 50% (KT50) values, expressed in minutes, were elicited by the essential oils of the Eucalyptus grandis X Eucalyptus tereticornis (57.9) hybrid, Eucalyptus sideroxylon A. Cunn (62.0), E. grandis X Eucalyptus camaldulensis (63.8) hybrid, Eucalyptus viminalis Labill (64.1), Eucalyptus dunnii Maiden (64.5), and Eucalyptus grandis (Hill) ex Maiden (68.7). The KT50 values for the remaining essential oils ranged between 74.5 (E. saligna Smith) and 161.4 min (E. tereticornis Smith). The essential oil from the hybrid E. grandis X E. tereticornis was 3.7 times less toxic than dichlorvos (positive control). The KT50 values of monoterpenes were 38.8 for alpha-pinene, 55.3 for 1,8-cineole, 175.6 for p-cymene, and 178.3 for gamma-terpinene. Alpha-pinene was 2.5 times less toxic than dichlorvos. There was a strong positive correlation between the fumigant activity of essential oils and their corresponding 1,8-cineole and alpha-pinene concentration. Repellency was quantified using a video tracking system. Two concentrations of monoterpenes were studied (7 and 70 microg/cm2). All compounds produced a light repellent effect but only when applied at 70 microg/cm2. In all cases, the repellent effect was less than that produced by the broad-spectrum insect repellent N,N-diethyl-3-methylbenzamide (positive control).     

Chemical variability in the essential oil of Hyptis suaveolens

The essential oils of Hyptis suaveolens plants collected from 11 localities of the Brazilian Cerrado region were investigated by GC-MS. Sabinene, limonene, biclyclogermacrene, beta-phellandrene and 1,8-cineole were the principal constituents. The results were submitted to principal component and chemometric cluster analysis which allowed three groups of essential oils to be distinguished with respect to the content of p-mentha-2,4(8)-diene, limonene/beta-phellandrene/gamma-terpinene and germacrene D/bicyclogermacrene. In patterns of geographic variation in essential oil composition indicated that the sesquiterpenes are mainly produced in the samples grown at lower latitudes.     

Volatile constituents of the fruit and leaf oils of Thuja orientalis L. grown in Iran

The composition of the hydrodistilled essential oils from the fruits and leaves of Thuja orientalis L. grown in Iran was analyzed by GC/MS. Nineteen and twenty-eight compounds have been identified in the volatile oils of the fruit and leaf, respectively. While the fruit oil contained alpha-pinene (52.4%), delta-3-carene (14.2%), alpha-cedrol (6.5%) and beta-phellandrene (5.1%), the leaf oil contained alpha-pinene (21.9%), alpha-cedrol (20.3%), delta-3-carene (10.5%) and limonen (7.2%) as the main components.     

Chemical composition and antimicrobial activity of the essential oils of the Amazon Guatteriopsis species

The essential oils of Guatteriopsis blepharophylla, Guatteriopsis friesiana and Guatteriopsis hispida were obtained by hydrodistillation and analysed by GC and GC/MS. The main compound found in the leaf oil of G. blepharophylla was caryophyllene oxide (1) (69.25%). The leaf oil of G. friesiana contained predominantly beta-eudesmol (2) (51.60%), gamma-eudesmol (3) (23.70%), and alpha-eudesmol (4) (14.56%). The major constituents identified in the leaf of G. hispida were beta-pinene (38.18%), alpha-pinene (30.77%) and (E)-caryophyllene (20.59%). The antimicrobial activity of the essential oils was evaluated against 11 species of microorganisms. The oil of G. friesiana exhibited significant antimicrobial activity for all microorganisms tested, whereas that of G. hispida and G. blepharophyla had potent activity against Rhodococcus equi with MIC of 50 microg mL(-1). The major constituents of each oil were also tested separately, and showed lower activity compared to the oils. Moreover, mixtures of the main constituents, in the same proportions found in G. friesiana and G. hispida oils, did not show the same activity as the original oils.     

Chemical Composition of the Essential Oil and Diethyl Ether Extract of Trinia glauca (L.) Dumort. (Apiaceae) and the Chemotaxonomic Significance of 5‐O‐Methylvisamminol

Analyses by GC, GC/MS, and NMR spectroscopy (1D‐ and 2D‐experiments) of the essential oil and Et₂O extract of Trinia glauca (L .) Dumort . (Apiaceae) aerial parts allowed a successful identification of 220 constituents, in total. The major identified compounds of the essential oil were (Z)‐falcarinol (10.6%), bicyclogermacrene (8.0%), germacrene D (7.4%), δ‐cadinene (4.3%), and β‐caryophyllene (3.2%), whereas (Z)‐falcarinol (47.2%), nonacosane (7.4%), and 5‐O‐methylvisamminol (4.0%) were the dominant constituents of the extract of T. glauca. One significant difference between the compositions of the herein and the previously analyzed T. glauca essential oils (only two reports) was noted. (Z)‐Falcarinol was the major constituent in our case, whereas germacrene D (14.4 and 19.6%) was the major component of the previously studied oils. Possible explanations for this discrepancy were discussed. 5‐O‐Methylvisamminol, a (furo)chromone identified in the extract of T. glauca, has a limited occurrence in the plant kingdom and is a possible excellent chemotaxonomic marker (family and/or subfamily level) for Apiaceae.     

Antimicrobial activity of six constituents of essential oil from Salvia

The antimicrobial activity of three Salvia species, i.e. S. santolinifolia, S. hydrangea and S. mirzayanii, essential oils were investigated. The essential oils were obtained from the aerial parts of plants and analyzed by GC-MS. The main constituents of aforementioned species were alpha-pinene (72.4%), beta-pinene (6.6%) and limonene (5.3%); beta-caryophyllene (25.1%), 1,8-cineol (15.2%) and caryophyllene oxide (11.5%); alpha-terpinenyl acetate (22.6%), 1,8-cineol (21.2%) and linalool (8.9%), respectively. Bioassays exhibited that the property of the oil of S. myrzayanii was superior to others. The antimicrobial activity of essential oil from Salvia species may well be due to the presence of synergy between six tested compounds (linalool, 1,8-cineol, alpha-pinene, beta-pinene, beta-caryophyllene and limonene) and other constituents of the oils with various degrees of antimicrobial activity. Among these, linalool and 1,8-cineol had the highest antimicrobial activity.     

Chemical composition and antimicrobial activity of volatile compounds of Tamarix boveana (Tamaricaceae)

The chemical composition of the Tamarix boveana volatile oils obtained from the whole aerial part, flowers, leaves and stems by steam distillation was analysed using gas chromatograph (GC)-flame ionization detectors (FID) and GC-MS. Sixty-two components were identified. Hexadecanoic acid (18.14%), docosane (13.34%), germacrene D (7.68%), fenchyl acetate (7.34%), Benzyl benzoate (4.11%) were found to be the major components in the whole aerial parts. This composition differed according to the tested part: 2.4 Nonadienal was the main compound in the flowers (12.13%) while germacrene D was the major component in leaves (31.43%) and hexadecanoic acid in the stems (13.94%). To evaluate in vitro antimicrobial activity, all volatile oils were tested against six Gram-positive and Gram-negative bacteria and four fungi. The T. boveana volatile oils exhibited an interesting antibacterial activity against all strains tested except Pseudomonas aeruginosa but no antifungal activity was detected.     

Antifungal activity of the essential oils from some species of the genus Pinus

The chemical composition of the essential oils from the needles of Pinus ponderosa (north american pine), P. resinosa (red pine) and P. strobus (eastern white pine) has been determined by GC/MS (FID). The essential oils from P. resinosa and P. ponderosa in comparison to P. strobus have been characterized by the higher content of beta-pinene (42.4%, 45.7% and 7.9% respectively). On the other hand, a-pinene (17.7%) and germacrene D (12.2%) were dominant compounds of P strobus. Moreover the essential oil from P. resinosa was more rich in myrcene-15.9%. Estragole and delta-3-carene, each one in amount ca 8% were identified only in P. ponderosa. The content of essential oils in the needles slightly varied--0.65%--P. resinosa, 0.4%--P strobus, 0.3%--P. ponderosa. The antifungal activity has been investigated towards Fusarium culmorum, F solani and F. poae. The strongest activity was observed for the essential oil from P. ponderosa, which fully inhibited the growth of fungi at the following concentrations--F. culmorum, F. solani at 2% and F. poae at 5%.     

Chemical Diversity among the Essential Oils of Wild Populations of Stachys lavandulifolia Vahl (Lamiaceae) from Iran

The variation of the essential‐oil composition among ten wild populations of Stachys lavandulifolia Vahl (Lamiaceae), collected from different geographical regions of Iran, was assessed by GC‐FID and GC/MS analyses, and their intraspecific chemical variability was determined. Altogether, 49 compounds were identified in the oils, and a relatively high variation in their contents was found. The major compounds of the essential oils were myrcene (0.0–26.2%), limonene (0.0–24.5%), germacrene D (4.2–19.3%), bicyclogermacrene (1.6–18.0%), δ‐cadinene (6.5–16.0%), pulegone (0.0–15.1%), (Z)‐hex‐3‐enyl tiglate (0.0–15.1%), (E)‐caryophyllene (0.0–12.9), α‐zingiberene (0.2–12.2%), and spathulenol (1.6–11.1%). For the determination of the chemotypes and the chemical variability, the essential‐oil components were subjected to cluster analysis (CA). The five different chemotypes characterized were Chemotype I (germacrene D/bicyclogermacrene), Chemotype II (germacrene D/spathulenol), Chemotype III (limonene/δ‐cadinene), Chemotype IV (pulegone), and Chemotype V (α‐zingiberene). The high chemical variation among the populations according to their geographical and bioclimatic distribution imposes that conservation strategies of populations should be made appropriately, taking into account these factors. The in situ and ex situ conservation strategies should concern all populations representing the different chemotypes.     

Chemical composition and fumigant toxicity of the essential oils from 16 species of Eucalyptus against Haematobia irritans (Diptera: Muscidae) adults

Oils extracted from various species of Eucalyptus (Eucalyptus badjensis Beuzev & Welch, Eucalyptus badjensis x Eucalyptus nitens, Eucalyptus benthamii variety dorrigoensis Maiden & Cambage, Eucalyptus botryoides Smith, Eucalyptus dalrympleana Maiden, Eucalyptus fastigata Deane & Maiden, Eucalyptus nobilis L.A.S. Johnson & K. D. Hill, Eucalyptus polybractea R. Baker, Eucalyptus radiata ssp. radiata Sieber ex Spreng, Eucalyptus resinifera Smith, Eucalyptus robertsonii Blakely, Eucalyptus rubida Deane & Maiden, Eucalyptus smithii R. Baker, Eucalyptus elata Dehnh, Eucalyptus fraxinoides Deane & Maiden, E. obliqua L'Hér) were obtained by hydrodistillation. The chemical composition of essential oils was determined by gas chromatography coupled to mass spectrometry. Essential oils were mainly composed of 1,8-cineole, alpha-pinene, alpha-terpineol, 4-terpineol, and p-cymene. Vapors from these essential oils and their major components were found to be toxic to Haematobia irritans (L.) (Diptera: Muscidae) adults. An aliquot of each oil was placed in a cylindrical test chamber, and the number of knocked down flies was recorded as a function of time. Knockdown time 50% was then calculated. Results showed that essential oil of E. polybractea had the highest knockdown activity of 3.44 min. A correlation was observed between the content of 1,8-cineole in the Eucalyptus essential oils and the corresponding toxic effect.     

Essential oils of Phlomis leucophracta,Phlomis chimerae and Phlomis grandiflora var. grandiflora from Turkey

The essential oils of three species of Phlomis from Turkey, Phlomis leucophracta, Phlomis chimerae and Phlomis grandiflora var. grandiflora have been studied. The main constituents of P. leucophracta essential oil were β-caryophyllene (20.2%), α-pinene (19.2%) and limonene (11.0%). This species also contained three diterpene derivatives, 15-isopimaradiene, manoyl oxide and epi-13-manoyl oxide that summed 1.4%. In P. chimerae the principal compounds were β-caryophyllene (31.6%), α-pinene (11.0%), germacrene D (6.1%), limonene (5.5%) and linalool (4.7%). In P. grandiflora var. grandiflora, germacrene D (45.4%), β-caryophyllene (22.8%) and bicyclogermacrene (4.9%) were among the principal derivatives.