Essential oil composition of four Lomatium Raf. species and their chemotaxonomy

The composition of the essential oils of Lomatium dasycarpum ssp. dasycarpum, Lomatium lucidum, Lomatium macrocarpum var. macrocarpum and Lomatium utriculatum is described. Identification of components was determined from their GC, GC/MS data and many were confirmed by coinjections with authentic samples. Several components were isolated by liquid and gas chromatographic techniques and their structures confirmed from their ¹H and ¹³C NMR spectral data. 2-Methyl and 3-methylbutanoates were the major components of L. dasycarpum fruits as well as stems and leaves oils. β-Phellandrene/limonene, decanal, dodecanal, bornyl acetate, germacrene D, α-humulene and bicyclogermacrene were the major components of the corresponding L. lucidum oils. α-Pinene and β-pinene were the major components of the fruit oil of L. macrocarpum. Its stem and leaf oil was rich in peucenin 7-methyl ether, β-caryophyllene, (Z)-3-hexenol, palmitic acid, linoleic acid and (E)-2-hexenal. Sabinene, (Z)-ligustilide, terpinen-4-ol, β-phellandrene/limonene, β-caryophyllene, myrcene, α-pinene and β-pinene were the major compounds in L. utriculatum fruit oil, while its stem and leaf oil was rich in (Z)-ligustilide, palmitic acid, terpinen-4-ol, linoleic acid and germacrene D. (Z)-Falcarinol was a major component of all the four root oils.     

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.     

Essential oil of Stachys aleurites from Turkey

The essential oil obtained from the aerial parts of the Turkish endemism Stachys aleurites (Lamiaceae) has been studied. The main constituents were sesquiterpene hydrocarbons: β-caryophyllene (33.7%), bicyclogermacrene (14.5%) and germacrene D (9.6%). The main monoterpene was α-pinene (8.4%). Some chemotaxonomical considerations have been provided.     

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.     

GC-MS analysis of the essential oils of Juniperus communis L. berries growing wild in the Molise region: Seasonal variability and in vitro antifungal activity

Juniperus communis L., also known as the common juniper, is a dioecious aromatic evergreen shrub and has been traditionally used in many countries as a diuretic, antiseptic, and digestive and as a flavor to aromatize certain alcoholic beverages. We analyzed the chemical variability in the volatile profiles from berries of J. communis, harvested in one of the oldest European parks, the National Park of Abruzzo, Lazio, and Molise (PNALM, Central Italy). We examined the berries in different phases of the biological cycle for 1 year (at six ripening stages). Hydrodistilled essential oils from the fresh berries were analyzed by gas chromatography–flame ionization detection (GC-FID), gas chromatography–mass spectrometry (GC-MS) and principal component analysis (PCA). A total of 90 components were detected, and remarkable qualitative and quantitative differences were observed in the chemical components during the ripening stages, from the green unripe berries to the bluish-black berries harvested at full maturity. The essential oils were an α-pinene (13.43–32.34%) chemotype. The monoterpene hydrocarbons decreased during the ripening with a progressive increase in sesquiterpenes such as germacrene D (12.29–17.59%) and β-caryophyllene (7.71–8.51%), which are the major components in ripe berry essential oils. The sesquiterpene hydrocarbon fraction (65.3–47.9%) also contained α-humulene, germacrene B, δ-cadinene, bicyclogermacrene, and eudesma 4(14),11 diene. Germacrene D and β-caryophyllene in high concentrations may be considered as marker components of the genus Juniperus from the Molise region. This particular chemical composition has been reported for the first time. It is interesting to note the presence of β-caryophyllene (7–11%), whose inhalation has been reported to affect anxiety and depression in a rat model. An in vitro antifungal assay showed that the essential oil from green and ripe berries inhibits the growth of Sclerotium rolfsii, a phytopathogen fungus that causes post-harvest diseases in many fruits and vegetables.     

Volatile compounds from some wild growing aromatic herbs of the Lamiaceae from southern France

Abstract

The composition of the volatile fraction in selected aromatic plants of the Lamiaceae from garrigue sites in southern France is described. Calamintha nepeta appeared heterogeneous. The oil was dominated by piperitone oxide, and piperitenone oxide or by pulegone and menthone. In Nepeta nepetella, nepetalactone, almost exclusively the (4a-α, 7α, 7a-β)-isomer, made up more than 85% of the essential oil. Dichloromethane extracts from Teucrium polium contained germacrene D or sabinene as main components, α-pinene, β-pinene and β-caryophyllene in varying proportions as further important constituents, and various minor components depending on the origin.     

马尾松枝条挥发性组分的鉴定及松墨天牛对其触角电生理反应

为研究松墨天牛Monochamus alternatus Hope取食期引诱剂,利用气相色谱-质谱(GC-MS)联用技术并与标样核对分析了马尾松(Pinus massoniana Lamb.)枝条挥发性气味的化学组成。结果表明,马尾松1年生、2年生、3年生枝条气味均由8种萜烯类物质组成,但各组分相对含量不同。经方差分析,α-蒎烯、莰烯、β-蒎烯、柠檬烯、萜品油烯、β-石竹烯在3种枝条中的相对百分含量的差异均达到极显著水平。1年生枝条中α-蒎烯、莰烯和萜品油烯的相对含量最小,分别为20.81%、0.43%和4.74%,而β-蒎烯、月桂烯和柠檬烯的相对含量最高,分别为12.37%、4.33%和4.53%。鉴定的化合物对松墨天牛雌雄成虫的触角电生理反应的实验,结果表明,松墨天牛雌雄成虫对α-蒎烯的反应最强,对β-石竹烯的反应最弱。     

Composition of turpentine from Pinus edulis wood oleoresin

Monoterpenoids and sesquiterpenoid hydrocarbons of Pinus edulis wood oleoresin were analyzed by chromatographic and spectroscopic methods. Monoterpenoid hydrocarbons (20·3%) were composed mainly of α-pinene, with camphene, β-pinene, 3-carene, sabinene, myrcene, limonene, β-phellandrene, trans-ocimene and terpinolene in secondary to trace amounts. Oxygenated terpenoids (0.28%) contained bornyl acetate and verbenone as major constituents, and linalool, camphor, terpinene-4-ol, citronellyl acetate, borneol, neral, α-terpineol, citronellol, nerol, and geraniol in smaller amounts. Oleoresin contained 1·1% of acetogenins, composed mainly of ethyl caprylate. Sesquiterpenoid hydrocarbons were high (5·7%) in oleoresin) and were composed of germacrene D as a major constituent (36·6%), of γ-amorphene, α-copaene, and longifolene as secondary constituents (5–20%), and β-farnesene, α- and γ-murolenes, β₁-, γ-, δ-, and ε-cadinenes, α-amorphene, δ-guaiene, sibirene, α-cubebene, β-copaene, β-ylangene, sativene, cyclosativene, β-bourbonene, α- and γ-humulenes, caryophyllene, α-longipinene and longicyclene in smaller amounts. Composition of P. edulis and of P. monophylla turpentines was found to be similar, with percentage of ethyl caprylate being the best distinguishing criterion.     

Relationship between volatile compounds of Picea likiangensis var. linzhiensis cone and host selection of Dioryctria abietella

This study aimed to determine the relationship between volatile compounds of Picea likiangensis var. linzhiensis cone and host selection of Dioryctria abietella. During the infestation of P. likiangensis var. linzhiensis by D. abietella, their cones and branches emitted volatile compounds, which were extracted using CH₂Cl₂ extraction and XAD₂ adsorption methods, and were analyzed using gas chromatography–mass spectrometry. Before and after overwintering, D. abietella larva preferred annually infested cones and their extracts, and adult D. abietella preferred to lay eggs on annually infested cones and healthy cones of the year, and the oviposition rate of adult D. abietella was 72% on branches with healthy cones of the year, and no egg was laid on branches with annually healthy cones or branches without cones. The volatile compounds after infestation, α- and β-pinene, were significantly higher in cones than those in other tissues; however, myrcene in cones was significantly lower than those in other tissues. The annually infested cones produced β-caryophyllene and (1S)-(-)-β-pinene, while the annually healthy cones and branches produced myrcene and 3-carene. The annually infested cones and their extracts attracted D. abietella larvae, while that of healthy cones and annually infested cones attracted the adults, indicating that the terpene compounds: α-pinene, β-pinene, (1S)-(-)-β-pinene, limonene, and β-caryophyllene are attractive to D. abietella, and the terpene compounds—myrcene and 3-carene—from the branch tissues may be repulsive to D. abietella.     

Chemical classification of the essential oils of the Iranian Salvia species in comparison with their botanical taxonomy

The essential oils of eight Salvia species collected from different localities in Iran were analyzed by gas chromatography/mass spectrometry (GC/MS). The analytical results were compared with those previously published for related Iranian sage species in order to identify chemical markers for these species. Salvia eremophila, S. hypoleuca, and S. reuteriana are endemic, while S. atropatana, S. chloroleuca, S. santolinifolia, S. aegyptiaca, and S. macrosiphon also grow wild in neighboring countries. We categorized the Iranian Salvia species into four main chemotypes according to their essential-oil constituents: those which are dominated by 1) monoterpenes, 2) mono- and sesquiterpenes, or 3) sesquiterpenes as the major constituents, and 4) those containing low-molecular-weight acids, aldehydes, and esters, and green-leaf volatiles (GLVs). Likely due to the chemical diversity of different Salvia chemotypes, this categorization was supported by principal component analysis (PCA) for the group sampled here, but not for the values reported in the literature. We identified the following chemical markers: α-pinene, β-pinene, 1,8-cineol, linalool, and borneol in monoterpene-rich species, or β-caryophyllene, germacrene D, bicyclogermacrene, spathulenol, and caryophyllene oxide in sesquiterpene-rich species. Among these, α-pinene, β-caryophyllene, and germacrene D are the most common and abundant in the Salvia species investigated. In accordance with their close biological taxonomy, the chemical similarity of the essential oils of S. santolinifolia and S. eremophila is so high that we may consider them chemically identical.     

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 γ-terpinene (5.30%), myrcene (2.25%) and α-pinene (1.30%). Nineteen compounds which could not be identified in the original oil were identified in the oxygenated fraction. Myrcene, linalool, α-pinene, β-pinene, limonene, nonanal, γ-terpinene, germacrene D, and perillyl alcohol were the active aroma components (FD-factor > 3⁶), whereas β-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.     

Identification des constituants de l'essence des aiguilles de Pinus pinaster

The chromatographic analysis of the volatile leaf oil of Pinus pinaster Ait. showed 42% of monoterpene hydrocarbons (α-pinene, camphene, β-pinene, myrcene, 3-carene, limonene, cis-ocimene, terpinolene, para-cymene, 35% of sesquiterpene hydrocarbons (cubebene, copaene, caryophyllene, humulene, germacrene D, α- and γ-muurolenes, δ- and γ-cadinenes) and 23% of oxygenated compounds including esters (linalyl, bornyl, geranyl, neryl and farnesyl acetates), alcohols (cis-hexenol, linalool, α-fenchol, trans-pinocarveol, terpinen-4-ol, α-terpineol, dihydrocarveol, guaiol, junenol and α-cadinol), one aldehyde (hexenal) and one ketone (piperitone). Three non terpenoid phenylethyl esters were also identified: phenylethyl isovalerate, methyl-2 burtyate and 3-3 dimethylacrylate. Some alcohols and mainly α-terpineol and linalool seemed to be formed during the steam distillation process, they were absent when the leaf oil was obtained by maceration of small portions of leaves in the usual solvents of terpenes.     

The composition and antibacterial activity of essential oils in three Ocimum species growing in Romania

In this study the glandular hair morphology, chemical composition and antimicrobial activity of the essential oils from three Ocimum species have been investigated (Ocimum basilicum L. var. Genovese, O. gratissimum and O. tenuiflorum). The indumentum shows little variation among the investigated species with both glandular and non-glandular hairs presents. Glandular hairs on the three species are peltate and capitate (with various cell numbers in the stalk and gland). The samples of essential oils obtained from the plant aerial organs by hydrodistillation have been analyzed by GC-MS. Linalool (65.38%, 74.22%, 38.60%), eugenol (5.26%, 3.47%, 10.20%) and tau-cadinol (8.18%, 3.47%, 10.20%) appear as the main components in Ocimum basilicum L. var. Genovese, O. gratissimum and O. tenuiflorum. The oils also contain lower levels of α-bergamotene, 1,8-cineole, germacrene D, β-ocimene, α-caryophyllene, camphor, and α-guaiene. All essential oils showed antibacterial activity against Staphylococcus aureus and Escherichia coli depending on their concentration. Ocimum basilicum L. var. Genovese oil produced the strongest antibacterial effect on S. aureus and E. coli.     

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%).     

Chemical composition of the cortical essential oil from Abies balsamea

Monoterpenoids and sesquiterpene hydrocarbons of Abies balsamea cortical oleoresin (Canada balsam) were analyzed by a combination of chromatographic and spectroscopic methods. Monoterpene hydrocarbons (21%) were composed of β-pinene, α-pinene, β-phellandrene, limonene, 3-carene, myrcene and camphene (listed in order of decreasing percentages), and oxygenated monoterpenes (0·4%) contained 4,4-dimethyl-2-cyclohepten-1-one, linalool, bornyl acetate, methylthymol, citronellyl acetate, α-terpineol, piperitone, citronellal, borneol, citronellol, two unknowns, and geraniol. From the sesquiterpene hydrocarbon fraction (1·1%) were isolated: longifolene, β-bisabolene, longipinene, an unknown, sativene, cyclosativene, cis-α-bisabolene, β-himachalene, α-himachalene, β-caryophyllene, γ-humulene, farnesene, longicyclene, an unknown, and β-selinene. Both himachalenes have been identified for the first time in Pinaceae outside of Cedrus; their co-occurrence with γ-humulene, longifolene, longipinene and longicyclene supports the biosynthetic mechanism by which all of these compounds arise through initial 1/11 cyclization of tran-cis-farnesylphosphate.     

Influence of environmental factors on content and composition of essential oil from common juniper ripe berry cones (Juniperus communis L.)

Abstract

The present study evaluated the influence of some environmental factors on the quantity and composition of essential oil (EO) in ripe berry cones of Juniperus communis L. The berry cones were collected from juniper shrubs growing wild at five localities of north-east Slovakia during the years 2012–2014. The EO yield ranged from 0.4 to 1.9%, depending on the locality and year. In the EO, eight monoterpenes (α-pinene, β-pinene, β-myrcene, sabinene, limonene, terpinene-4-ol, borneol, bornylacetate) and one sesquiterpene (β-caryophyllene) were identified. The dominant component was the monoterpene α-pinene, ranging from 31.0 to 49.0%. The amount and composition of the EO was affected by soil composition (content of humus and pH) and topographic environmental factors, including air temperature and precipitation. According to the composition of the EO, the studied juniper shrubs belong to the α-pinene chemotype.     

Chemical composition and antimicrobial activity of the essential oil of endemic Dalmatian black pine (Pinus nigra ssp. dalmatica)

The chemical composition and the antimicrobial activity of the essential oil isolated from the needles of endemic Dalmatian black pine (Pinus nigra ssp. dalmatica) from Croatia were investigated. The chemical composition of the essential oil was determined by GC and GC/MS analyses, and the main compounds identified were α-pinene, β-pinene, germacrene D, and β-caryophyllene. Disc-diffusion and broth-microdilution assays were used for the in vitro antimicrobial screening. The Dalmatian black pine essential oil exhibited a great potential of antibacterial activity against Gram-positive bacteria (MIC=0.03-0.50% (v/v)) and a less pronounced activity against Gram-negative bacteria (MIC=0.12-3.2% (v/v)). The volatile compounds also inhibited the growth of all fungi tested, including yeast.     

Volatiles from Marina neglecta: Biocide effect on insect vectors of tropical diseases in Southern Mexico

Preventive measures based in the control of insect vectors are considered as the best choice to decrease the incidence of insect-borne diseases. Herein we report on the volatile content of the leaf essential oils from Marina neglecta, a medicinal plant distributed in the tropical regions of southern Mexico. In order to investigate the chemical variation of the essential oils, a volatile screening was performed during the four seasons of the years 2016–2019. Simultaneously, their biological activity was tested on distinct life stages of Meccus pallidipennis, M. bassolsae, Aedes aegypti and A. albopictus. Essential oils were mainly constituted of β-pinene (>30%) β-caryophyllene (>25%) and germacrene D (>13%). Dorsal-abdomen application of essential oils on triatomines, revealed an efficient LC₅₀ for nymphs of the stages I to III (4 µg/insect), nymphs of the stages IV to V (5–6 µg/insect), and adults (7–8 µg/insect). The LT₅₀ for the stages I to III was between 6 and 8 h, whereas that for the stages IV to V and adults oscillated between 12 and 16 h and 22 to 26 h, respectively. Fumigation experiments performed on nymph V, demonstrated that 300 µg L^?1 air produced 100% mortality after 72 h post-treatment. Among tested volatiles, β-pinene and β-caryophyllene produced a comparable mortality rate (p < 0.01) than that of essential oils in the stages assayed. Essential oils showed strong larvicidal (LC₅₀, 24–36 µg mL^?1) and adulticidal (35–48 µg mL^?1) activities in mosquito species with an LT₅₀ of 4.5 h and 25–35 min, respectively. The evaluation of β-pinene produced a significant mortality rate (p < 0.01) in larvae whereas germacrene D was the most effective volatile (p < 0.01) against adults of both mosquito species. According to our results, β-pinene was the most effective volatile against the four insect species evaluated and its effect was comparable to that of the essential oil.     

Composition and antimicrobial activity of the essential oil of six Hypericum species from Serbia

The volatile composition of six Hypericum species has been studied. The essential oils were obtained by steam distillation in 500 mL H₂O for 2 h in a modified Clevenger apparatus with a water-cooled oil receiver to reduce hydrodistillation over-heating artifacts, and their analyses were performed by GC and GC–MS. Identification of the substances was made by comparison of mass spectra and retention indices with literature records. A total of 100 different compounds were identified. The main constituents of the investigated populations of each taxon have been revealed as follows: Hypericum alpinum: (−)-β-pinene, γ-terpinene, (−)-(E)-caryophyllene; Hypericum barbatum: (−)-α-pinene, (−)-β-pinene, (−)-limonene, (−)-(E)-caryophyllene, (−)-caryophyllene oxide; Hypericum rumeliacum: (−)-α-pinene, (−)-β-pinene, (−)-limonene, Hypericum hirsutum: nonane, undecane, (−)-(E)-caryophyllene, (−)-caryophyllene oxide; Hypericum maculatum: spathulenol, globulol; Hypericum perforatum: (−)-α-pinene, (Z)-β-farnesene, germacrene D; Monoterpene hydrocarbons were shown to be the main group of the taxa belonging to the section Drosocarpium, while the taxa of section Hypericum were more rich in sesquiterpene hydrocarbons.     

Phenological variations of secondary metabolites from Hypericum triquetrifolium Turra

The essential oils and phenolic constituents from the aerial parts of Hypericum triquetrifolium Turra, were analyzed at three developmental stages (vegetative, flowering and fruiting stages). The highest content of oil (0.12% w/w) was obtained at full flowering. Whatever the analyzed stage, n-octane, α-pinene, β-caryophyllene, 2-methyloctane, n-nonane, α-longipinene, caryophyllene oxide and β-pinene were found to be the main compounds. However, their percentages varied with the phenological cycle. Analysis by RP-HPLC-DAD of the methanolic extracts enabled us to identify 14 phenolic components and rutin, hyperoside, quercitrin and quercetin were reported as the main components. With the exception of chlorogenic acid, kaempferol and amentoflavone, the content of the remaining identified phenolic components varied with the phonological cycle.