Essential oil yield,composition, bioactivity and leaf morphology of Juniperus oxycedrus L. from Bulgaria and Serbia

Juniperus oxycedrus L. (Cupressaceae Bartlett) is widely distributed in countries with a Mediterranean climate. All plant parts contain highly aromatic essential oil (EO) and recently there have been efforts to introduce it as a cultivated crop. The species is known for its large morphological and chemical variation and its debatable taxonomic status. This study aimed to (1) compare content, composition, and antimicrobial activity of J. oxycedrus EO samples from plants growing in Bulgaria and Serbia, and (2) quantify morphological variations of leaves. Тhe EO content (yield) in dried juniper leaves varied from 0.06% (Кopaonik, Serbia) to 0.24% (Markovo, Bulgaria). We identified 51 EO constituents, belonging to monoterpenes, sesquiterpenes, and diterpenes. The class monoterpenes (monoterpene hydrocarbons and oxygenated monoterpenes) were the predominant compounds, representing 38.6–65.4% of the total EO, consisting primarily of α-pinene, limonene, sabinene, β-pinene, and β-myrcene. In addition, α-pinene was the major oil constituent in plants from all locations. Sesquiterpenes (sesquiterpene hydrocarbons and oxygenated sesquiterpenes) were the second largest class of constituents, which represented 19.3% tо 33.6% of the total EO. γ-Elemene was found only in the EO of J. oxycedrus from Bulgaria, while a high concentration of α-curcumene was found only in samples from Serbia (7.5–7.8%). Significant differences in antimicrobial activity of the EO were found in bacterial strains Bacillus cereus and Streptococcus pneumoniae. There was no significant difference among the mean leaf width of the six combinations location x sex, and the overall leaf mean width was 1.24 mm. However, there was a significant difference between the mean leaf lengths. In this study, none of the studied populations had a higher concentration of limonene than of α-pinene, indicating that the flora of the two countries include J. oxycedrus and not the previously reported J. deltoides. The results revealed significant variation in EO profile that may contribute to the development of new cultivars of J. oxycedrus.     

Pseudotsuga menziesii (Pinaceae): Volatile Profiles,Antimicrobial Activity and Toxicological Evaluation of Its Essential Oil

The present article investigates the chemical composition of volatiles of essential oil (EO) and headspace (HS) fraction, as well as biological activities of EO obtained from needles with twigs of Pseudotsuga menziesii var. menziesii cultivated in Serbia. The major class of compounds was monoterpene hydrocarbons with α-terpinolene, sabinene and β-pinene (EO), and sabinene, α-terpinolene and β-pinene (HS) as the dominant volatiles. Tested EO exhibited mostly low antimicrobial potential against investigated strains (ATCC and respiratory isolates), where MICs ranged 1.25–20.00 mg/mL. Nevertheless, based on presented results, where antimicrobial testing was done for the first time on human respiratory system isolates, there is a potential of this EO to be used as an adjuvant in the treatment of human respiratory infections, especially those caused by Pseudomonas aeruginosa or Candida albicans strains. Regarding toxicological evaluation, EO showed moderate toxicity in Artemia salina toxicity bioassay (LC₅₀=347.41, after 24 h) as well as week toxicity against Drosophila melanogaster with the ability only to moderately delay larval and pupal development.     

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.     

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.     

The leaf oil terpene composition of Juniperus occidentalis

The chemical composition of the volatile oil of 10 trees each of two Oregon populations of the western juniper was determined by a computerized GC-MS method. The identity of the major components, sabinene, α-pinene, α- and γ-terpinene, p-cymene, limonene, terpinen-4-ol and bornyl acetate was confirmed. In addition, tricyclene, α-thujene, camphene, β-pinene, α- and β-phellandrene, car-3-ene, trans-ocimene, linalool oxide, terpinolene, trans-sabinene hydrate, camphor, camphene hydrate, borneol, α-terpineol, p-cymenol, methyl citronellate, citronellyl acetate, carvacrol, cuminic aldehyde, β-bourbonene, several cadinene and cadinol isomers, elemol, γ-, β- and α-eudesmol, and manoyl oxide were identified. Santene, citronellol, and aromatic ethers of the safrole-eugenol type were not found. Tree-to-tree variability of the relative percentages of these terpenes was fairly large and chemosystematic implications are discussed briefly.     

Essential Oil of Azorella cryptantha Collected in Two Different Locations from San Juan Province, Argentina: Chemical Variability and Anti-Insect and Antimicrobial Activities

The essential oils (EOs) of two populations of Azorella cryptantha (Clos) Reiche, a native species from San Juan Province, were obtained by hydrodistillation in a Clevenger-type apparatus and characterized by GC-FID and GC/MS analyses. The compounds identified amounted to 92.3 and 88.7% of the total oil composition for A. cryptantha from Bauchaceta (Ac-BAU) and Agua Negra (Ac-AN), respectively. The EO composition for the two populations was similar, although with differences in the identity and content of the main compounds and also in the identity of minor components. The main compounds of the Ac-BAU EO were α-pinene, α-thujene, sabinene, δ-cadinene, δ-cadinol, trans-β-guaiene, and τ-muurolol, while α-pinene, α-thujene, β-pinene, γ-cadinene, τ-cadinol, δ-cadinene, τ-muurolol, and a not identified compound were the main constituents of the Ac-AN EO, which also contained 3.0% of oxygenated monoterpenes. The repellent activity on Triatoma infestans nymphs was 100 and 92% for the Ac-AN and Ac-BAU EOs, respectively. Regarding the toxic effects on Ceratitis capitata, the EOs were very active with LD(50) values lower than 11?μg/fly. The dermatophytes Microsporum gypseum, Trichophyton rubrum, and T. mentagrophytes and the bacterial strains Escherichia coli LM(1) , E. coli LM(2) , and Yersinia enterocolitica PI were more sensitive toward the Ac-AN EO (MIC 125?μg/ml) than toward the Ac-BAU EO. This is the first report on the composition of A. cryptantha EO and its anti-insect and antimicrobial properties.     

Application of methyl jasmonate to grey willow (<Emphasis Type="Italic">Salix cinerea</Emphasis>) attracts insectivorous birds in nature

It has been suggested that insectivorous birds may be guided by herbivore-induced plant volatiles (HIPVs) to herbivore-rich trees with herbivorous damage. The HIPV production in plants is partly mediated by jasmonic acid signalling pathway. Methyl jasmonate (MeJA) was proved to be a suitable agent for induction of HIPVs similar to those induced by herbivorous insects in many plant species. We studied the effects of methyl jasmonate on volatile emission and natural enemy attraction using mature grey willow (Salix cinerea) under natural conditions in Czech Republic. We treated 12 experimental shrubs with 30 mM MeJA and completed the experiment with 12 control shrubs. We monitored attacks by natural predators with artificial plasticine caterpillars which were checked daily. Birds most often pecked the caterpillars exposed on MeJA-treated shrubs and this attractiveness differed significantly from control. Attractiveness of MeJA-treated shrubs did not differ significantly from control shrubs for arthropod predators. Spraying MeJA on grey willows resulted in significantly higher production of α-pinene, β-pinene, 3-carene, limonene and β-ocimene. There was a marginally significant positive correlation between the predation rate by birds and relative change in α-pinene emissions.     

Testing what we know about coffee volatiles affecting behaviour of Hypothenemus hampei

Coffee berry borer (CBB), Hypothenemus hampei (Ferrari) (Coleoptera: Scolytinae), is a major pest of coffee worldwide. CBB females use berry volatiles while searching for hosts. Coffee volatiles can be used for monitoring CBB populations. The main objective of this study was to test under laboratory and field conditions bioactive compounds for H. hampei. In the laboratory, CBB females were attracted to the methanol-ethanol blend (MEB), but not to methylcyclohexane, ethylbenzene, nonane, methyl salicylate, verbenone, α-pinene, farnesene, and frontalin compared to clean air. In contrast, CBB females preferred clean air over linalool. Females were attracted to most of the tested compounds combined with the MEB over clean air, except farnesene, α-pinene, and linalool. Females preferred clean air to α-pinene or linalool, and they showed no preference for clean air or farnesene. Females also preferred the MEB over linalool, verbenone, α-pinene, or farnesene when combined with MEB. The combination of tested compounds and the MEB did not increase the capture of CBB in the field. Interestingly, α-pinene and linalool alone, or combined, inhibited the capture of CBB females and non-target insects by trapping bait with the MEB. Thus, α-pinene or linalool can be used in a push-pull strategy considering the low impact over non-target insects.     

Chemical Composition,Antibacterial Screening and Cytotoxic Activity of Chiliadenus antiatlanticus (Asteraceae) Essential Oil

The chemical composition and in vitro antibacterial and cytotoxic activities of the essential oil (EO) of Chiliadenus antiatlanticus (Emb. & Maire) Gómiz, an asteraceous species endemic to the southwest of Morocco, were investigated. The EO yield was 1.07±0.28 %, twenty-seven metabolites were identified representing more than 96.4 % of the total composition. Camphor (35.7 %) and derivatives, borneol (4.9 %) and camphene (4.2 %) together with intermedeol (19.9 %), α-pinene (15.5 %) and (E)-pinocarveol (4.1 %) were the major constituents. An antibacterial activity was noticed against 24 strains (all Gram-positive) out of 71 at MICs values=100 μg/mL. The EO also showed significant toxicity towards liver HepG2 (55.8 % of cell viability) and melanoma B16 4A5 (41.6 % of cell viability) tumor cell lines at 100 μg/mL.     

Dr. Alfred Jeske 75 jahre

The chemical composition, phytotoxic and antifungal activities of the essential oils isolated by hydrodistillation from the needles of Tunisian Aleppo pine harvested from different provenances were evaluated. The chemical composition analysed by gas chromatography/mass spectrometry (GC/MS) revealed variability among provenances displaying interesting chemotypes, (Z)-caryophyllene (16.16–28.9%), β-myrcene (8.5–22.9%), α-pinene (11.7–13.14%), β-pinene (3.13–11.8%), bicyclogermacrene (5.2–12.37%), α-terpinolene (8.11–11.01%) and α-humulene (2.85–5.2%), which were the main components in the oil. Antifungal ability of Aleppo pine oils was tested by disc agar diffusion against 10 phytopathogenic fungi. Weak antifungal activity was observed for the essential oils isolated. Furthermore, in contrast, the herbicidal activity investigated for three common weeds in Tunisian cereal crops was very strong and seed germination was inhibited at a low concentration and their herbicidal effects were higher than those of a commercial herbicide.     

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.     

Studies on Leaf Oils of Citrus Species

Leaf oil samples of four Japanese citrus species were analysed by gas chromatography to determine the detailed composition of each leaf oil. The following components were identified: α-pinene, α-thujene, camphene, β-pinene, sabinene, β-myrcene, α-terpinene, limonene, β-phellandrene, trans-2-hexen-1-al, γ-terpinene, p-cymene, terpinolene, cis-2-penten-1-ol, n-hexyl alcohol, cis-3-hexen-1-ol, trans-2-hexen-1-ol, p-α-dimethylstyrene linalool, linalyl acetate, β-elemene, terpinen-4-ol, caryophyllene, humulene, α-terpineol, neryl acetate, geranyl acetate, β-selinene, geraniol and thymol. Most components were contained in common in leaf oils of the four citrus species, but relative contents of some of the components; such as γ-terpinene, linalyl acetate, and thymol differed from species to species. For example, γ-terpinene was the major component (33.8%) of Hassaku, whereas it was only a minor component in Daidai. Daidai is characterized by a very high content of linalyl acetate (35%) which is only a trace in the other three species. Kishu-mikan is characterized by a high content of thymol (15%).     

Bactericidal and antioxidant effects of essential oils from Satureja montana L., Myristica fragrans H. and Cymbopogon flexuosus

The extraction and characterization of the essential oils (EO) from Satureja montana L., Myristica fragrans H. and Cymbopogon flexuosus and the determination of their antibacterial and antioxidant activities were achieved. The EO were identified by gas chromatography/mass spectrometry and quantified by gas chromatography using a flame ionization detector. The antibacterial potential against Escherichia coli and Staphylococcus aureus was evaluated by cell susceptibility assays and by scanning electron microscopy. The antioxidant activity was evaluated by the 2,2-diphenyl-1-picrylhydrazyl assay, by β-carotene bleaching and by determining the reducing power. Borneol (36·18%), γ-terpineol (12·66%) and carvacrol (11·07%) were the principal components in the EO from S. montana, and sabinene (49·23%) and α-pinene (13·81%) were found in the EO from M. fragrans. Geranial (59·66%) and neral (38·98%) isomers were the only major components in the EO from C. flexuosus. The EO from S. montana was effective against E. coli, with minimum inhibitory and bactericidal concentrations (MIC and MBC) of 6·25 µl ml⁻¹, whereas bactericidal potential against both was observed for the EO from M. fragrans; MIC = 6·25 µl ml⁻¹ for S. aureus and MBC = 12·5 µl ml⁻¹ for E. coli. A significant protective role on lipid substrates in the β-carotene bleaching assay was seen for the EO from S. montana and M. fragrans. Overall, such EO can be promising agents against pathogenic bacteria and for protecting biomolecules during oxidative stress.     

Chemodiversity and α-Glucosidase Activity of Eucalyptus Species from Northwestern Himalaya,India

The aim of current work was to determine essential oils (EOs) composition from three Eucalyptus species, including E. citriodora, E. camaldulensis and E. globulus and assess their α-glucosidase inhibitory activity. The EOs were collected using the hydrodistillation technique and characterized by GC/MS, GC-FID and NMR. The isolated EOs from leaves parts of Eucalyptus species varied from 0.56 to 1.0 % on fresh weight basis. The content of the EOs was distinct according to the species. The most abundant metabolites were identified as citronellal (0–83.0 %), 1,8-cineole (0.2–44.8 %), spathulenol (0.4–16.1 %) α-pinene (0.4–15.9 %), p-cymene (3.7–11.9 %), citronellol (0–8.6 %), β-eudesmol (5.3–8.6 %) and β-pinene (0–7.1 %). The EOs obtained from targeted samples exhibited strong α-glucosidase inhibitory activity. These results are encouraging and underline that the EOs of Eucalyptus species may be a promising alternative source of natural antidiabetic.     

Chemical profile and biological activities of Cedrelopsis grevei H. Baillon bark essential oil

Cedrelopsis grevei H. Baillon bark, endemic plant from Madagascar, is used in folk medicine for the treatment of rheumatism, muscular pain, and for its antifungal and antibiotic activities. In this paper, the phytochemical composition, antioxidant, antimicrobial, and cytotoxic activities of C. grevei bark essential oil (EO), its non-polar (I and II) and polar (III) fractions and its main compounds (ishwarane, β-elemene and α-copaene) were investigated.

The GC–MS analysis pointed out the presence of 36 components, representing about 80% as semi-quantitative characterization of the total. The presence of ishwarane, β-elemene and α-copaene as the main constituents highlighted its peculiar composition as a sesquiterpene-rich phytocomplex. Moreover, the quantification was performed for the first time by means of the experimental and predicted response factors (ERFs and PRFs, respectively).

As regards the biological activity, C. grevei EO and its fractions showed weak antioxidant activity against Trolox. The whole EO demonstrated instead considerable antimicrobial activity against Staphylococcus aureus and Staphylococcus epidermidis, while its polar-fraction evidenced an interesting bioactivity against Pseudomonas aeruginosa and Candida albicans. Finally, C. grevei EO and its fractions exhibited an interesting cytotoxic activity on human lung cancer cells (A549) and human colorectal cancer cells (CaCo-2).     

Anisakis simplex s.l.: Larvicidal activity of various monoterpenic derivatives of natural origin against L3 larvae in vitro and in vivo

This paper describes the activity against Anisakis simplex s.l. L₃ larvae of six monoterpenic derivatives obtained from different essential oils, (α-pinene, β-pinene, ocimene, myrcene, geranyl acetate, and cineole). In in vitro assays, α-pinene, ocimene and cineole showed high activity at a concentration of 125 μg/mL (48 h) but only α-pinene and ocimene were active at 62.5 μg/mL. In in vivo assays, L₃ larvae and study compounds were simultaneously administered per os to Wistar rats. The most active compound was α-pinene, finding lesions in only 20% of treated rats versus 98% of controls. Further in vivo studies are required to investigate whether addition of these compounds to food could have a prophylactic effect, reducing the pathogenicity of A. simplex s.l. L₃ in humans, and to explore any possible synergy among compounds.     

Consequence of salinity and excess boron on growth, evapotranspiration and ion uptake in date palm (Phoenix dactylifera L., cv. Medjool)

Patches of common juniper (Juniperus communis L.) shrubs potentially facilitate the formation of fertile islands in heath tundra ecosystems thereby influencing the long-term resilience of these ecosystems. Although the role of juniper in the formation of such ‘islands of fertility’ has been studied in semiarid landscapes, there has been little attention paid to the importance of juniper in other ecosystems. In this study we contrast the soil fertility and rates of N fixation under juniper shrubs with that in open heath tundra in northern Sweden. Plots were established at several individual sites in alpine heath tundra in Northern Sweden and mineral soils to a depth of 10 cm were characterized for available N and P and total C, N, P, Ca, Mg, K, Fe, Mn, Zn, and Cu. Nitrogen fixation rates were measured by acetylene reduction in feather mosses under juniper canopies and contrasted with N fixation in both feather mosses and surface soils in the open heath. Soils under juniper had concentrations of total P greatly in excess of P in open heath, furthermore, juniper islands had the highest concentrations of bioavailable P. Nitrogen fixation rates in the feather moss Pleurozium schreberi (Bird.) Mitt were approximately 150 μmol acetylene reduced m⁻² d⁻¹ under the juniper canopy compared to less than 10 μmol acetylene reduced m⁻² d⁻¹ in the open heath. Feather mosses under the juniper canopy also fixed N at a significantly higher rate (on an aerial basis) than that of surface cores from the open heath that included lichen, mosses, and soil crusts. Juniper facilitates the formation of islands of soil fertility that may in turn facilitate the growth of other plants and positively influence the long term recovery of heath tundra ecosystems following disturbance.     

Light-dependent monoterpene synthesis in Pinus radiata cultures

Callus cultures of Pinus radiata that synthesized monoterpenes de novo and which were stable for at least 1 year have been established. The products differed from those of parent plants in that α-pinene (87–100%) rather than β-pinene was the main component. The best lines accumulated monoterpenes (ca 2 × 10^?3% wt/wet wt)in yields 40–20% of that in the parent stem and needles. The composition of the extractable oil depended on the light regime. After culture in total darkness toluene and acetone accumulated. These compounds also occurred (at low levels) in dark-grown seedlings and in seeds of P. radiata and a route for their formation from α-pinene is suggested. Cell-free extracts of the culture lines converted [¹⁴C] IPP into geraniol, nerol and α- and β-pinenes in up to 46% total yield. These are the most active crude extracts for monoterpene biosynthesis that have been reported from either tissue cultures or higher plants.     

Composition and variability of essential oils of Platycladus orientalis growing in China

Essential oils were isolated from the leaves of Platycladus orientalis growing in 16 areas of China. The essential oils were analyzed by gas chromatography and gas chromatography-mass spectrometry. In total, 98 volatile compounds were identified. Chemical variability in essential oil composition was evaluated using cluster analysis and principal component analysis. The two analyses led to the identification of four chemotypes: α-pinene, α-pinene/3-carene, cedrol, and cedrol/terpinyl acetate. Geographically, the populations growing in close proximity had similar essential oil composition. The chemical variability could possibly be attributed to genetic and environmental factors.     

不同危害状态下寄主萜烯挥发物含量的变化及松墨天牛对其组分的触角电位反应

用气相色谱-质谱（GC-MS）联用法对5种生理状态（健康、人为物理损伤、饵木、取食和产卵）的马尾松Pinus massoniana和取食危害状态的雪松Cedrus deodara的萜烯进行分析。研究结果显示,5种生理状态下,α-蒎烯在萜烯组分中均占有最高比例。健康状态下马尾松树干和树枝中的萜烯组分不同且含量有显著差异。随着饵木的衰弱进程,α-蒎烯的相对含量显著减少,β-蒎烯的含量显著增加,我们推测,α-蒎烯与β-蒎烯的相对比例越小则寄主树势衰弱的程度越深,其两者比例的变化是马尾松寄主树势衰弱程度变化的一个重要信号。人为物理损伤的马尾松树干与树枝的α-蒎烯、β-蒎烯和β-水芹烯含量差异显著。不同产卵危害程度的马尾松树干萜烯类组分不同,同一产卵危害程度的马尾松树干上部和下部的多数萜烯组分相对含量差异显著,但变化无明显规律。取食危害状态下马尾松和雪松萜烯种类不同且含量差异显著。重度产卵危害马尾松树干与取食危害树枝萜烯中,α-蒎烯、β-蒎烯、柠檬烯和β-水芹烯相对含量差异显著。第13天的饵木与人为物理损伤的马尾松树干的萜烯中,饵木的β-蒎烯和柠檬烯相对百分含量均比人为物理损伤状态的高,而α-蒎烯则相反。α-蒎烯和β-蒎烯在取食危害树枝中的含量显著高于健康树枝,而β-月桂烯、β水芹烯和反式石竹烯在健康状态树枝中的含量显著高于取食危害树枝。除了α-蒎烯和β蒎烯,健康状态与产卵危害状态的马尾松树干萜烯相对含量大都差异显著。α-蒎烯,β-蒎烯和β-水芹烯在人为物理损伤与虫害状态的马尾松树干及树枝中含量差异较大。总之,α-蒎烯、β-蒎烯和β-水芹烯很可能是影响和调节松墨天牛取食和产卵行为最为重要的信号物质。松墨天牛Monochamus alternatus Hope对寄主萜烯的触角电位（EAG）表明,该天牛对β-蒎烯的EAG活性高于其他萜烯,乙醇也能引起较高的EAG反应活性,但总体上对单一萜烯的EAG反应活性不强,且存在雌雄差异。