caryophyllene and linalool

Dental medicine is one of the fields of medicine where the most common pathologies are of bacterial and fungal origins. This review is mainly focused on the antimicrobial effects of cinnamon essential oil (EO), cinnamon extracts, and pure compounds against different oral pathogens and the oral biofilm and the possible effects on soft mouth tissue. Basic information is provided about cinnamon, as is a review of its antimicrobial properties against the most common microorganisms causing dental caries, endodontic and periodontal lesions, and candidiasis. Cinnamon EO, cinnamon extracts, and pure compounds show significant antimicrobial activities against oral pathogens and could be beneficial in caries and periodontal disease prevention, endodontics, and candidiasis treatment.

Topics: Acrolein; Acyclic Monoterpenes; Anti-Bacterial Agents; Anti-Infective Agents; Bacteria; Biofilms; Candida; Cinnamomum zeylanicum; Clinical Trials as Topic; Dental Caries; Eugenol; Humans; Microbial Sensitivity Tests; Oils, Volatile; Plant Bark; Plant Leaves; Polycyclic Sesquiterpenes

It is well known that duration of pre-drying storage impacts on hop quality. However, little knowledge exists regarding its actual effects on valuable hop components. To investigate these effects, fresh hop cones were stored for 5 or 24 h and dried for 210 min at 65 °C thereafter. Furthermore, to understand the effect of freezing hop cones on the essential oil content, both fresh and stored samples were frozen before and after drying.. The results from gas chromatography analysis show an increase in linalool, β-caryophyllene, humulene, geraniol content and decrease in myrcene content dependent on the period of storage. Total colour difference ΔE values of 4.61 and 5.27 were obtained for fresh and stored hops respectively, indicating discoloration of hops during storage. Modelling of moisture curves revealed the Wang and Singh model to be suitable, with. The results from this study provide an in-depth understanding on the changes occurring within the hop cones both during storage and drying and will further help hop processors optimize their storage times.

Topics: Acyclic Monoterpenes; Alkenes; Chromatography, Gas; Desiccation; Food Handling; Hot Temperature; Humulus; Monocyclic Sesquiterpenes; Oils, Volatile; Polycyclic Sesquiterpenes; Time Factors

Topics: Acyclic Monoterpenes; Anti-Bacterial Agents; Antineoplastic Agents, Phytogenic; Antioxidants; Asteraceae; Bacillus subtilis; Cell Line, Tumor; Cytotoxins; Gas Chromatography-Mass Spectrometry; Humans; Microbial Sensitivity Tests; Monoterpenes; Oils, Volatile; Plant Extracts; Polycyclic Sesquiterpenes; Sesquiterpenes; Staphylococcus aureus

Foods and beverage aroma results from multicomponent mixtures of volatile compounds present in the food that interact with olfactory receptors and produce a perceptual response in the brain. However, the perceptual interactions that occur when complex odor mixtures are combined are not well understood. Here we used Gas chromatography-Recomposition-Olfactometry (GC-R) to better understand the role that individual compounds have on the perceived sensory aroma of bitters. Bitters are the concentrated alcoholic extract of flavorful plant materials with a wide range of complex sensory and chemical aroma profiles that have not been extensively studied. Previously, we demonstrated that Angostura bitters are characterized by complex aroma attributes described as cola, ginger, orange peel, and black pepper and that the volatile composition of Angostura bitters is predominantly composed of terpenoids. Using GC-R to create in-instrument mixtures of the Angostura headspace extracts, the sensory attributes of Angostura extracts with linalool, α-terpinyl-acetate and caryophyllene omitted were evaluated. The omission experiments demonstrated direct and indirect effects of the individual compounds on the aroma attributes of Angostura bitters, through masking, additive, and synergistic interactions. Caryophyllene in particular, which was present in the headspace extracts at concentration only slightly above sensory threshold levels, had a large and unexpected impact on the sensory properties of the mixtures and may be most responsible for the aromas associated with the whole sample. The GC-R and statistical approaches used here provided valuable tools to reveal relationships among individual compounds and aroma attributes of foods that have not been currently theorized using existing analytical approaches.

Topics: Acyclic Monoterpenes; Adult; Chromatography, Gas; Citrus; Female; Flavoring Agents; Garcinia kola; Humans; Male; Odorants; Olfactometry; Piper nigrum; Plant Extracts; Polycyclic Sesquiterpenes; Terpenes; Zingiber officinale

Terpenoids are a large group of important secondary metabolites that are involved in a variety of physiological mechanisms, and many are used commercially in the cosmetics and pharmaceutical industries. During the past decade, the topic of seasonal variation in terpenoid biosynthesis has garnered increasing attention. Formosan sweet gum ( Liquidambar formosana Hance) is a deciduous tree species. The expression of terpene synthase and accumulation of terpenoids in leaves may vary in different seasons. Here, four sesquiterpene synthases (i.e., LfTPS01, LfTPS02, LfTPS03, and LfTPS04) and a bifunctional mono/sesquiterpene synthase ( LfTPS05) were identified from Formosan sweet gum. The gene expression of LfTPS01, LfTPS02, and LfTPS03 showed seasonal diversification, and, in addition, expression of LfTPS04 and LfTPS05 was induced by methyl jasmonate treatment. The major products LfTPS01, LfTPS02, LfTPS04, and LfTPS05 are hedycaryol, α-selinene, trans-β-caryophyllene, α-copaene/δ-cadinene, and nerolidol/linalool, respectively. The data indicated that the sesquiterpenoid content in the essential oil of Formosan sweet gum leaves shows seasonal differences that were correlated to the sesquiterpene synthase gene expression.

Topics: Acyclic Monoterpenes; Alkyl and Aryl Transferases; Gene Expression; Liquidambar; Monoterpenes; Plant Leaves; Plant Proteins; Polycyclic Sesquiterpenes; Seasons; Sesquiterpenes

The profile and bioactivity of hops (Humulus lupulus L.) essential oil, a complex natural product extracted from cones via steam distillation, depends on genetic and environmental factors, and may also depend on extraction process. We hypothesized that compound mixtures eluted sequentially and captured at different timeframes during the steam distillation process of whole hop cones would have differential chemical and bioactivity profiles. The essential oil was collected sequentially at 8 distillation time (DT) intervals: 0-2, 2-5, 5-10, 10-30, 30-60, 60-120, 120-180, and 180-240 min. The control was a 4-h non-interrupted distillation. Nonlinear regression models described the DT and essential oil compounds relationship. Fractions yielded 0.035 to 0.313% essential oil, while control yielded 1.47%. The oil eluted during the first hour was 83.2%, 9.6% during the second hour, and only 7.2% during the second half of the distillation. Essential oil (EO) fractions had different chemical profile. Monoterpenes were eluted early, while sequiterpenes were eluted late. Myrcene and linalool were the highest in 0-2 min fraction, β-caryophyllene, β-copaene, β-farnesene, and α-humulene were highest in fractions from middle of distillation, whereas α- bergamotene, γ-muurolene, β- and α-selinene, γ- and δ-cadinene, caryophyllene oxide, humulne epoxide II, τ-cadinol, and 6-pentadecen-2-one were highest in 120-180 or 180-240 min fractions. The Gram-negative Escherichia coli was strongly inhibited by essential oil fractions from 2-5 min and 10-30 min, followed by oil fraction from 0-2 min. The strongest inhibition activity against Gram-negative Yersinia enterocolitica, and Gram-positive Clostridium perfringens, Enterococcus faecalis, and Staphylococcus aureus subs. aureus was observed with the control essential oil. This is the first study to describe significant activity of hops essential oils against Trypanosoma brucei, a parasitic protozoan that causes African trypanosomiasis (sleeping sickness in humans and nagana in other animals). Hops essential oil fractions or whole oil may be used as antimicrobial agents or for the development of new drugs.

Topics: Acyclic Monoterpenes; Alkenes; Antiprotozoal Agents; Bridged Bicyclo Compounds; Clostridium perfringens; Distillation; Drug Resistance, Bacterial; Enterococcus faecalis; Escherichia coli; Humulus; Monocyclic Sesquiterpenes; Monoterpenes; Oils, Volatile; Plant Extracts; Polycyclic Sesquiterpenes; Sesquiterpenes; Staphylococcus aureus; Steam; Trypanosoma brucei brucei; Yersinia enterocolitica

Emerald ash borer (EAB; Agrilus planipennis) is a devastating pest of ash (Fraxinus spp.) in its invaded range in North America. Its coevolved Asian hosts are more resistant and less preferred for oviposition than susceptible North American species. We compared EAB oviposition preferences and bark and canopy volatile organic compound (VOC) emissions of resistant Manchurian ash and susceptible black ash, and examined relationships between VOC profiles and oviposition. In the field, black ash was highly preferred for oviposition while no eggs were laid on Manchurian ash, and we found clear differences in the VOC profiles of Manchurian and black ash. We detected 78 compounds emitted from these species, including 16 compounds that elicited EAB antennal activity in prior studies. Four compounds were unique to black and 11 to Manchurian ash. Emission rates of 14 canopy and 19 bark volatiles varied among the two species, including four previously reported as antennally active. Specifically, 7-epi-sesquithujene (bark) emissions were greater from black ash, while β-caryophyllene (canopy), linalool (bark), and α-cubebene (bark) were emitted at higher rates by Manchurian ash. No relationships were found between the emission rate of any single compound or group of compounds (e.g. monoterpenes) suggesting that preference may be based on complex profile combinations. This is the first study to directly compare VOCs of black and Manchurian ash as well as the first to examine bark- and canopy-specific VOCs. The unique bark and canopy VOC profiles of these two species implicates potentially important variation in VOCs between a closely related resistant and susceptible species that provides a foundation for future studies of host preferences of EAB.

Topics: Acyclic Monoterpenes; Animals; Coleoptera; Female; Fraxinus; Gas Chromatography-Mass Spectrometry; Monocyclic Sesquiterpenes; Monoterpenes; Oviposition; Plant Bark; Plant Leaves; Polycyclic Sesquiterpenes; Sesquiterpenes; Volatile Organic Compounds

Topics: Acyclic Monoterpenes; Antioxidants; Benzothiazoles; Biphenyl Compounds; Gas Chromatography-Mass Spectrometry; Monoterpenes; Oils, Volatile; Picrates; Plant Extracts; Polycyclic Sesquiterpenes; Scutellaria; Sesquiterpenes; Sesquiterpenes, Germacrane; Sulfonic Acids; Uzbekistan

Melicope belahe (Baill.) T.G. Hartley (Rutaceae) is an endemic species to Madagascar. The chemical composition of leaf essential oil is reported for the first time. A sample was extracted by hydrodistillation and analysis was carried out by combination of chromatographic (GC), spectroscopic and spectrometric (MS,

Topics: Acyclic Monoterpenes; Bicyclic Monoterpenes; Madagascar; Magnetic Resonance Spectroscopy; Monoterpenes; Oils, Volatile; Plant Leaves; Polycyclic Sesquiterpenes; Rutaceae; Sesquiterpenes

African rice gall midge, Orseolia oryzivora Harris and Gagné, is a major pest of rice in Africa. Depsite its economic importance, its chemical ecology is not well understood. Here, we assessed behavioral and electrophysiological responses of O. oryzivora to host plant volatiles. In olfactometer bioassays, mated female O. oryzivora were attracted to volatiles emitted from intact rice plants but were repelled by volatiles collected from plants infested by conspecifics. In a choice test, there was a preference for volatiles from uninfested plants over those from infested plants. Coupled gas chromatography-electroantennography analyses of panicle volatiles isolated four electrophysiologically active components: (S)-linalool, 4,8-dimethyl-1,3,7-nonatriene, (E)-caryophyllene, and (R/S)-(E)-nerolidol. A synthetic blend of volatiles at the same concentration and ratio as that from an intact plant was attractive to mated females, whereas a blend based on the ratio of volatiles from an infested plant was repellent. This suggests that O. oryzivora uses olfaction for host plant recognition. The identification of blends of volatiles emitted by plants that can both attract and repel O. oryzivora may aid the development of sustainable control measures.

Topics: Acyclic Monoterpenes; Animals; Behavior, Animal; Diptera; Electrophysiological Phenomena; Female; Gas Chromatography-Mass Spectrometry; Host-Parasite Interactions; Monoterpenes; Odorants; Olfactometry; Oryza; Polycyclic Sesquiterpenes; Seedlings; Sesquiterpenes; Terpenes; Volatilization

SPME-GC-MS analysis of the scent of Platanthera bifolia subsp. osca collected during the night showed as main components lilac alcohols B, C and D and lilac aldehydes A, B and C. Other significant chemical components were linalool and caryophyllene. Some differences were found in comparison with previously reported analyses of the scent of P. bifolia and Platanthera chlorantha. The most important difference found was in the composition of the ester fraction.

Topics: Acyclic Monoterpenes; Alcohols; Aldehydes; Gas Chromatography-Mass Spectrometry; Monoterpenes; Odorants; Orchidaceae; Polycyclic Sesquiterpenes; Sesquiterpenes; Solid Phase Microextraction; Syringa

The essential oil constituents of the leaves of Jasminum subtriplinerve (Oleaceae) and Vitex quinata (Verbanaceae) cultivated in Vietnam were analysed by gas chromatography--flame ionisation detector (GC-FID) and gas chromatography--mass spectrometry (GC-MS) techniques. The main constituents identified in J. subtriplinerve were mainly oxygenated monoterpenes represented by linalool (44.2%), α-terpineol (15.5%), geraniol (19.4%) and cis-linalool oxide (8.8%). The quantitative significant components of V. quinata were terpene hydrocarbons comprising of β-pinene (30.1%), β-caryophyllene (26.9%) and β-elemene (7.4%). The chemical compositions of the essential oils are being reported for the first time.

Topics: Acyclic Monoterpenes; Bicyclic Monoterpenes; Bridged Bicyclo Compounds; Cyclohexane Monoterpenes; Cyclohexenes; Flame Ionization; Gas Chromatography-Mass Spectrometry; Jasminum; Monoterpenes; Oils, Volatile; Plant Leaves; Plant Oils; Polycyclic Sesquiterpenes; Sesquiterpenes; Terpenes; Vietnam; Vitex

Absorption of hop volatiles by crown cork liner polymers and can coatings was investigated in beer during storage. All hop volatiles measured were prone to migrate into the closures, and the absorption kinetics was demonstrated to fit Fick's second law of diffusion well for a plane sheet. The extent and rate of diffusion were significantly dissimilar and were greatly dependent upon the nature of the volatile. Diffusion coefficients ranged from 1.32 × 10(-5) cm(2)/day (limonene) to 0.26 × 10(-5) cm(2)/day (α-humulene). The maximum amounts absorbed into the material at equilibrium were in the following order: limonene > α-humulene > trans-caryophyllene > myrcene ≫ linalool > α-terpineol > geraniol. With the application of low-density polyethylene (LDPE) liners with oxygen-scavenging functionality, oxygen-barrier liners made up from high-density polyethylene (HDPE) or liner polymers from a different manufacturer had no significant effect on the composition of hop volatiles in beers after prolonged storage of 55 days; however, significantly higher amounts of myrcene and limonene were found in the oxygen-barrier-type crown cork, while all other closures behaved similarly. Can coatings were demonstrated to absorb hop volatiles in a similar pattern as crown corks but to a lesser extent. Consequently, significantly higher percentages of myrcene were found in the beers.

Topics: Acyclic Monoterpenes; Alkenes; Beer; Cyclohexane Monoterpenes; Cyclohexenes; Gas Chromatography-Mass Spectrometry; Humulus; Limonene; Monocyclic Sesquiterpenes; Monoterpenes; Polycyclic Sesquiterpenes; Polyethylene; Polymers; Sesquiterpenes; Terpenes

In natural habitats plants can be exposed to brief and light contact with neighbouring plants. This mechanical stimulus may represent a cue that induces responses to nearby plants. However, little is known about the effect of touching on plant growth and interaction with insect herbivores. To simulate contact between plants, a soft brush was used to apply light and brief mechanical stimuli to terminal leaves of potato Solanum tuberosum L. The number of non-glandular trichomes on the leaf surface was counted on images made by light microscope while glandular trichomes and pavement cells were counted on images made under scanning electronic microscope. Volatile compounds were identified and quantified using coupled gas chromatography-mass spectrometry (GC-MS). Treated plants changed their pattern of biomass distribution; they had lower stem mass fraction and higher branch and leaf mass fraction than untouched plants. Size, weight and number of tubers were not significantly affected. Touching did not cause trichome damage nor change their total number on touched terminal leaves. However, on primary leaves the number of glandular trichomes and pavement cells was significantly increased. Touching altered the volatile emission of treated plants; they released higher quantities of the sesquiterpenes (E)-β-caryophyllene, germacrene D-4-ol and (E)-nerolidol, and lower quantities of the terpenes (E)-ocimene and linalool, indicating a systemic effect of the treatment. The odour of touched plants was significantly less preferred by the aphids Macrosiphum euphorbiae and Myzus persicae compared to odour of untouched plants. The results suggest that light contact may have a potential role in the detection of neighbouring plants and may affect plant-insect interactions.

Topics: Acyclic Monoterpenes; Alkenes; Animals; Aphids; Herbivory; Mechanotransduction, Cellular; Monoterpenes; Plant Leaves; Plant Stems; Polycyclic Sesquiterpenes; Sesquiterpenes; Sesquiterpenes, Germacrane; Solanum tuberosum; Touch; Trichomes

Plant essential oils (EOs) can potentially replace synthetic fungicides in the management of postharvest fruit and vegetable diseases. The aim of this study was to evaluate in vitro and in vivo effectiveness of thymol, carvacrol, linalool, and trans-caryophyllene, single constituents of the EO of Origanum vulgare L. ssp. hirtum against Monilinia laxa, M. fructigena, and M. fructicola, which are important phytopathogens and causal agents of brown rot of pome and stone fruits in pre- and postharvest. Moreover, the possible phytotoxic activity of these constituents was assessed and their minimum inhibitory concentration (MIC) was determined. In vitro experiment indicated that thymol and carvacrol possess the highest antifungal activity. Results of in vivo trials confirmed the strong efficacy of thymol and carvacrol against brown rot of peach fruits. The thymol MIC resulted to be 0.16 μg/μL against M. laxa and M. fructigena and 0.12 μg/μL against M. fructicola, whereas for carvacrol they were 0.02 μg/μL against the first two Monilinia species and 0.03 μg/μL against the third. Results of this study indicated that thymol and carvacrol could be used after suitable formulation for controlling postharvest fruit diseases caused by the three studied Monilinia species.

Topics: Acyclic Monoterpenes; Antifungal Agents; Ascomycota; Cymenes; Fruit; Microbial Sensitivity Tests; Monoterpenes; Oils, Volatile; Origanum; Plant Diseases; Polycyclic Sesquiterpenes; Prunus persica; Sesquiterpenes; Thymol

This investigation focused on the qualitative and quantitative composition of essential oil compounds of European Origanum vulgare. Extracts of 502 individual O. vulgare plants from 17 countries and 51 populations were analyzed via GC. Extracts of 49 plants of 5 populations of Israeli Origanum syriacum and 30 plants from 3 populations of Turkish Origanum onites were included to exemplify essential oil characteristics of 'high-quality' oregano. The content of essential oil compounds of European O. vulgare ranged between 0.03% and 4.6%. The monoterpenes were primarily made up of sabinene, myrcene, p-cymene, 1,8-cineole, β-ocimene, γ-terpinene, sabinene hydrate, linalool, α-terpineol, carvacrol methyl ether, linalyl acetate, thymol and carvacrol. Among the sesquiterpenes β-caryophyllene, germacrene D, germacrene D-4-ol, spathulenol, caryophyllene oxide and oplopanone were often present in higher amounts. According to the proportions of cymyl-compounds, sabinyl-compounds and the acyclic linalool/linalyl acetate three different main monoterpene chemotypes were defined. The cymyl- and the acyclic pathway were usually active in plants from the Mediterranean climate whereas an active sabinyl-pathway was a characteristic of plants from the Continental climate.

Topics: Acyclic Monoterpenes; Alkenes; Bicyclic Monoterpenes; Cyclohexane Monoterpenes; Cyclohexanols; Cyclohexenes; Cymenes; Eucalyptol; Europe; Monoterpenes; Oils, Volatile; Origanum; Polycyclic Sesquiterpenes; Sesquiterpenes; Sesquiterpenes, Germacrane; Thymol

The rapid emergence of multi- and extensively drug-resistant tuberculosis (MDR/XDR-TB) has created a pressing public health problem, which mostly affects regions with HIV/AIDS prevalence and represents a new constraint in the already challenging disease management of tuberculosis (TB). The present work responds to the need to reduce the number of contagious MDR/XRD-TB patients, protect their immediate environment, and interrupt the rapid spread by laying the groundwork for an inhalation therapy based on anti-TB-active constituents of the essential oil (EO) of Eucalyptus citriodora. In order to address the metabolomic complexity of EO constituents and active principles in botanicals, this study applied biochemometrics, a 3-D analytical approach that involves high-resolution CCC fractionation, GC-MS analysis, bioactivity measurements, and chemometric analysis. Thus, 32 airborne anti-TB-active compounds were identified in E. citriodora EO: the monoterpenes citronellol (1), linalool (3), isopulegol (5), and α-terpineol (7) and the sesquiterpenoids spathulenol (11), β-eudesmol (23), and τ-cadinol (25). The impact of the interaction of multiple components in EOs was studied using various artificial mixtures (AMxs) of the active monoterpenes 1, 2, and 5 and the inactive eucalyptol (33). Both neat 1 and the AMx containing 1, 2, and 33 showed airborne TB inhibition of >90%, while the major E. citriodora EO component, 2, was only weakly active, at 18% inhibition.

Topics: Acyclic Monoterpenes; Antitubercular Agents; Cyclohexane Monoterpenes; Cyclohexanols; Cyclohexenes; Databases, Factual; Eucalyptol; Eucalyptus; Female; Gas Chromatography-Mass Spectrometry; Humans; Male; Molecular Structure; Monoterpenes; Oils, Volatile; Plant Leaves; Sesquiterpenes, Eudesmane; Tuberculosis; Tuberculosis, Multidrug-Resistant

As a peculiar folk medicinal plant, Acanthopanax brachypus was widely used to treat various diseases in China. At present, however, there is not a good quality standard for its quality evaluation. In this study, on the basis of the validation tests of precision, stability and repeatability, the chromatographic fingerprint of A. brachypus was established by using gas chromatography (GC)-flame ionization detector (FID) and GC-MS techniques, as well as computer aided similarity evaluation system. Thirty-two different batches of samples collected from the different producing regions and the different parts of A. brachypus were studied. The results showed that the dominant constituents of all oils were monoterpenes and sesquiterpenes, as well as oxygenated monoterpenes and sesquiterpenes. The fingerprinting profiles were found to be consistent for the fresh stem bark acquired from various production areas, 48 common peaks were determined, but the relative abundance of peaks was varied. β-Pinene, linalool, p-cymene, spathulenol, camphene, endo-borneol, verbenone, β-caryophyllene, γ-terpinene, germacrene-D, camphor, β-thujone and β-cadinene were the main constituents of the fresh stem bark oil. Except for the leaf, the chemical components among different medicinal parts of fresh plant were inconsistent with the stem bark. Besides, the varieties and relative levels of chemical components in the fresh stem bark were more abundant than in the dry counterpart. The GC-MS fingerprint can be successfully applied to distinguish the substitute or adulterant, and further assess the differences of A. brachypus grown in various areas of China.

Topics: Acyclic Monoterpenes; Bicyclic Monoterpenes; Bridged Bicyclo Compounds; Cyclohexane Monoterpenes; Cymenes; Eleutherococcus; Gas Chromatography-Mass Spectrometry; Monoterpenes; Polycyclic Sesquiterpenes; Sesquiterpenes; Sesquiterpenes, Germacrane; Terpenes

Solid-phase microextraction technique coupled with gas chromatography-flame ionisation detector and gas chromatography-mass spectrometry was used to investigate the inter- and intra-population chemical polymorphism in volatile constituents of three populations of Thymus pannonicus growing in Slovakia. To have an idea on what really the plant emits under different environmental and physiological conditions, a total of 86 individuals were separately analysed using low extraction temperatures (30°C). Data were analysed using a chemometric approach such as the principal component analysis which revealed a significant intra-population variability with the existence of up to four chemotypes: the most abundant is the p-cymene/γ-terpinene chemotype, followed by the geraniol and linalool chemotypes, and, only in one population, by the γ-muurolene/(E)-caryophyllene chemotype. This differentiation of individual plants inside the populations allows better adaptation to ecological conditions of localities and is probably connected with intrinsic genetic diversity of the species.

Topics: Acyclic Monoterpenes; Cyclohexane Monoterpenes; Cymenes; Gas Chromatography-Mass Spectrometry; Monoterpenes; Oils, Volatile; Polycyclic Sesquiterpenes; Principal Component Analysis; Sesquiterpenes; Slovakia; Solid Phase Microextraction; Terpenes; Thymus Plant

Entomopathogenic nematodes (EPNs) respond to a variety of stimuli when foraging. In a laboratory investigation, we tested the chemotactic responses of 8 EPN strains (Steinernema and Heterorhabditis) to three mechanically damaged maize root compounds (linalool, α-caryophyllene and β-caryophyllene). We hypothesized that the EPN directional response to the tested volatile compounds would vary among the species and volatile compound and may be related to foraging strategies. The nematodes with an intermediate foraging strategy (Steinernema feltiae) proved to be less active in their movement toward volatile compounds in a comparison with the ambushers (Steinernema carpocapsae) and cruisers (Steinernema kraussei and Heterorhabditis bacteriophora); β-caryophyllene was found to be the most attractive substance in our experiment. The results of our investigation showed that the cruisers were more attracted to β-caryophyllene than the ambushers and intermediates. The foraging strategy did not affect the movement of the IJs toward the other tested volatile compounds or the control. Our results suggest that the response to different volatile cues is more a strain-specific characteristic than a different host-searching strategy. Only S. carpocapsae strain B49 displayed an attraction to linalool, whereas S. kraussei showed a retarded reaction to β-caryophyllene and α-caryophyllene in our experiment. The EPN strains showed only a weak attraction to α-caryophyllene, suggesting that this volatile compound could not have an important role in the orientation of IJs to the damaged roots of maize plants. These results expand our knowledge of volatile compounds as the cues that may be used by EPNs for finding hosts or other aspects of navigation in the soil.

Topics: Acyclic Monoterpenes; Analysis of Variance; Animals; Chemotaxis; Monocyclic Sesquiterpenes; Monoterpenes; Movement; Plant Roots; Polycyclic Sesquiterpenes; Rhabditida; Rhabditoidea; Sesquiterpenes; Soil; Time Factors; Volatilization; Zea mays

Terpenes are specialized plant metabolites that act as attractants to pollinators and as defensive compounds against pathogens and herbivores, but they also play an important role in determining the quality of horticultural food products. We show that the genome of cultivated apple (Malus domestica) contains 55 putative terpene synthase (TPS) genes, of which only 10 are predicted to be functional. This low number of predicted functional TPS genes compared with other plant species was supported by the identification of only eight potentially functional TPS enzymes in apple 'Royal Gala' expressed sequence tag databases, including the previously characterized apple (E,E)-α-farnesene synthase. In planta functional characterization of these TPS enzymes showed that they could account for the majority of terpene volatiles produced in cv Royal Gala, including the sesquiterpenes germacrene-D and (E)-β-caryophyllene, the monoterpenes linalool and α-pinene, and the homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene. Relative expression analysis of the TPS genes indicated that floral and vegetative tissues were the primary sites of terpene production in cv Royal Gala. However, production of cv Royal Gala floral-specific terpenes and TPS genes was observed in the fruit of some heritage apple cultivars. Our results suggest that the apple TPS gene family has been shaped by a combination of ancestral and more recent genome-wide duplication events. The relatively small number of functional enzymes suggests that the remaining terpenes produced in floral and vegetative and fruit tissues are maintained under a positive selective pressure, while the small number of terpenes found in the fruit of modern cultivars may be related to commercial breeding strategies.

Topics: Acyclic Monoterpenes; Alkyl and Aryl Transferases; Base Sequence; Bicyclic Monoterpenes; Flowers; Fruit; Gas Chromatography-Mass Spectrometry; Gene Expression Profiling; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Plant; Genomics; Malus; Molecular Sequence Data; Monoterpenes; Multigene Family; Phylogeny; Plant Proteins; Polycyclic Sesquiterpenes; Reverse Transcriptase Polymerase Chain Reaction; Sequence Homology, Nucleic Acid; Sesquiterpenes; Species Specificity; Terpenes; Volatile Organic Compounds; Volatilization

The essential oils of four wild growing Origanum vulgare L. (family Lamiaceae) collected from different locations in Kumaon region (Uttarakhand, India) were analysed by capillary GC and GC/MS. The comparative results of O. vulgare L. collected from four different regions showed differences in the chemical constituents of the essential oils. The oil of O. vulgare L. collected from Dhoulchina and Champawat (chemotype I) shows p-cymene (6.7-9.8%), γ-terpinene (12.4-14.0%), thymol (29.7-35.1%) and carvacrol (12.4-20.9%) as major constituents while the oil from Kilbury and Rushi village (chemotype II) shows linalool (6.7-9.7%), bornyl acetate (12.6-16.8%), β-caryophyllene (10.5-13.8%) and germacrene D (6.3-11.3%) as the major constituents. These features highlight the chemosystematics of this genus.

Topics: Acyclic Monoterpenes; Biomarkers; Camphanes; Chromatography, Gas; Cyclohexane Monoterpenes; Cymenes; Gas Chromatography-Mass Spectrometry; Geography; India; Monoterpenes; Oils, Volatile; Origanum; Polycyclic Sesquiterpenes; Sesquiterpenes; Sesquiterpenes, Germacrane; Species Specificity; Thymol

The chemical composition of essential oil from pine needles (Cedrus deodara) was determined, and its antioxidant and antimicrobial activities were evaluated. Twenty-three components, representing 95.79% of the oil, were identified by gas chromatography mass spectrometry. The main components include α-terpineol (30.2%), linalool (24.47%), limonene (17.01%), anethole (14.57%), caryophyllene (3.14%), and eugenol (2.14%). Pine needle essential oil showed remarkable antioxidant activity in scavenging free radicals, in lipid peroxidation, and in reducing power assays. Moreover, the essential oil revealed strong antimicrobial activity against typical food-borne microorganisms, with minimum inhibitory concentration and minimum bactericidal concentration values of 0.2 to 1.56 and 0.39 to 6.25 μg/mL, respectively. Transmission electron microscope observation ascertained that the bactericidal mechanism of pine needle essential oil may be the induction of cytoplasmic outflow and plasmolysis. These results suggest that the essential oil from pine needles has potential to be used as a natural antioxidant and antimicrobial agent in food processing.. The present study provides a theoretical basis for the potential application of essential oil from pine needles (C. deodara) to be used as a natural resource of antioxidant and antimicrobial agents in food industry.

Topics: Acyclic Monoterpenes; Allylbenzene Derivatives; Anisoles; Anti-Infective Agents; Antioxidants; Bacteria; Cedrus; Cyclohexane Monoterpenes; Cyclohexenes; Fungi; Limonene; Lipid Peroxidation; Microbial Sensitivity Tests; Monoterpenes; Oils, Volatile; Plant Oils; Polycyclic Sesquiterpenes; Sesquiterpenes; Terpenes

In response to insect attack, plants release complex blends of volatile compounds. These volatiles serve as foraging cues for herbivores, predators and parasitoids, leading to plant-mediated interactions within and between trophic levels. Hence, plant volatiles may be important determinants of insect community composition. To test this, we created rice lines that are impaired in the emission of two major signals, S-linalool and (E)-β-caryophyllene. We found that inducible S-linalool attracted predators and parasitoids as well as chewing herbivores, but repelled the rice brown planthopper Nilaparvata lugens, a major pest. The constitutively produced (E)-β-caryophyllene on the other hand attracted both parasitoids and planthoppers, resulting in an increased herbivore load. Thus, silencing either signal resulted in specific insect assemblages in the field, highlighting the importance of plant volatiles in determining insect community structures. Moreover, the results imply that the manipulation of volatile emissions in crops has great potential for the control of pest populations.

Topics: Acyclic Monoterpenes; Animals; Hemiptera; Herbivory; Monoterpenes; Oryza; Parasites; Pest Control; Polycyclic Sesquiterpenes; Population Dynamics; Sesquiterpenes; Volatilization

The aroma-active compounds in Chinese bayberry were identified using gas chromatography-olfactometry (GC-O) and GC-mass spectrometry techniques. The volatile compounds were extracted using Liquid-liquid extraction, solvent-assisted flavor evaporation and headspace solid-phase microextraction (HS-SPME), respectively. On the basis of odor intensity, the most important aroma compounds in Chinese bayberry samples were caryophyllene, menthol, 4-terpineol, linalool oxide, linalool, benzyl alcohol, α-methylbenzyl alcohol, β-phenylethanol, 3-methylbutanoic acid and acetic acid, and so on. Moreover, HS-SPME technique was employed to investigate the aroma compounds among immature and mature waxberry fruits. The results showed that terpenes (for example, β-caryophyllene) was predominant and its concentration represented over 89.9% of the overall compounds, and alcohols, aldehydes, ketones, esters, acids, and others were typically present in lesser amounts. Finally, principal component analysis revealed that there was also significant difference between immature and mature waxberry fruits.

Topics: Acyclic Monoterpenes; Benzyl Alcohol; Benzyl Alcohols; Chromatography, Gas; Fruit; Gas Chromatography-Mass Spectrometry; Liquid-Liquid Extraction; Monoterpenes; Myrica; Odorants; Phenylethyl Alcohol; Polycyclic Sesquiterpenes; Sesquiterpenes; Solid Phase Microextraction; Solvents; Taste; Volatile Organic Compounds

Herbivory, mechanical injury or pathogen infestation to vegetative tissues can induce volatile organic compounds (VOCs) production, which can provide defensive functions to injured and uninjured plants. In our studies with 'McNeal' wheat, 'Otana' oat, and 'Harrington' barley, plants that were mechanically injured, attacked by either of two Oulema spp. (melanopus or cyanella) beetles, or infected by one of the three Fusarium spp. (graminearum, avenaceum, or culmorum), had significant VOC induction compared to undamaged plants. Mechanical injury to the main stem or one leaf caused the induction of one green leaf volatile (GLV) - (Z)-3-hexenol, and three terpenes (β-linalool, β-caryophyllene, and α-pinene) with all three grasses; wheat and barley also showed β-linalool oxide induction. The blend of induced VOCs after Fusarium spp. infestation or Oulema spp. herbivory was dominated by GLVs ((Z)-3-hexenal, (E)-2-hexenal, (E)-2-hexenol, (Z)-3-hexenyl acetate, and 1-hexenyl acetate) and β-linalool and β-caryophyllene; beetle herbivory also induced (E)-β-farnesene. Different ratios of individual VOCs were induced between the two Oulema spp. for each cereal grass and different ratios across the three cereals for each beetle species. Also, different ratios of individual VOCs were induced between the three Fusarium spp. for each cereal grass and different ratios across the three cereals for each fungal pathogen species. Our results are preliminary since we could not simultaneously measure VOC induction from controls with each of the ten different injury treatments for each of the three cereals. However, the comparison of mechanical injury, insect herbivory, and fungal infection has not been previously examined with VOC responses from three different plant species within the same family. Also, our work suggests large qualitative and quantitative overlap of VOC induction from plants of all three cereals having beetle herbivory injury when compared to infection injury from necrotrophic fungal pathogens.

Topics: Acyclic Monoterpenes; Animals; Bicyclic Monoterpenes; Coleoptera; Fusarium; Hexanols; Monoterpenes; Plant Diseases; Plant Leaves; Poaceae; Polycyclic Sesquiterpenes; Sesquiterpenes; Volatile Organic Compounds

The essential oils yield and composition of the aerial parts of A. annua var. CIM-Arogya grown in Uttarakhand, India were analyzed and compared by capillary GC and GC-MS at different stages of development. The analysis led to the identification of 81 constituents forming 91.0%-97.1% of the essential oils compositions. The essential oil content of the aerial parts was found to vary from 0.3% to 0.7% at different stages of growth. A. annua crop harvested at full flowering and seed setting stage gave higher yield of essential oil (0.6%, 0.7%) than that harvested at pre flowering (0.5%), late vegetative (0.4%, 0.5%), mid vegetative (0.4%, 0.4%) and early vegetative stages (0.3%, 0.3%). The essential oils at different stages of growth showed monoterpenoids (38.5%-72.0%) and sesquiterpenoids (22.2%-48.2%) as major grouped constituents. The major constituents identified were camphor (22.8%-42.6%), 1,8-cineole (3.7%-8.4%), linalool (<0.1%-11.9%), beta-caryophyllene (2.0%-9.2%), (E)-beta-farnesene (1.3%-8.5%), germacrene D (0.5%-7.3%) and 1-epi-cubenol (0.7%-5.2%) in essential oil samples collected at different crop stages.

Topics: Acyclic Monoterpenes; Artemisia annua; Camphor; Cyclohexanols; Eucalyptol; Gas Chromatography-Mass Spectrometry; Monoterpenes; Oils, Volatile; Polycyclic Sesquiterpenes; Sesquiterpenes; Sesquiterpenes, Germacrane

The leaves of Alchornea floribunda and Alchornea cordifolia are used traditionally as topical anti-inflammatory agents. In this study, two highly lipophilic fractions AFLF and ACLF isolated from A. floribunda and A. cordifolia leaves respectively were investigated for topical anti-inflammatory effects using xylene-induced mice ear oedema as a model of inflammation. AFLF and ACLF at 5 mg per ear showed significant (p < 0.01) topical anti-inflammatory effect with oedema inhibitions of 64.0% and 79.0% at 2 h, respectively. When compared to indomethacin (5 mg per ear), these fractions showed significantly (p < 0.05) higher topical anti-inflammatory effect. Gas chromatography-mass spectrometry analysis revealed that AFLF is composed mainly of long chain saturated and unsaturated hydrocarbons (18.78%) and their oxygenated derivatives (1.89%); while ACLF is rich in volatile oils eugenol (21.26%) and cadinol (4.76%), and other constituents like, nanocosaine (36.86%) and steroid derivatives, ethyl iso-allocholate (4.59%) and 3-acetoxy-7,8-epoxylanostan-1-ol (15.86%). Analysis of the volatile oil (ACV) extracted from the fresh leaves of A. cordifolia revealed the presence of high concentrations of eugenol (41.7%), cadinol (2.46%), Caryophylene (1.04%), Linalool (30.59%) and (E)-α-bergamotene (4.54%). These compounds could be contributing to the topical anti-inflammatory effects of A. floribunda and A. cordifolia leaf extracts.

Topics: Acyclic Monoterpenes; Administration, Topical; Animals; Anti-Inflammatory Agents; Bridged Bicyclo Compounds; Edema; Eugenol; Euphorbiaceae; Gas Chromatography-Mass Spectrometry; Hydrocarbons; Mice; Monoterpenes; Oils, Volatile; Plant Extracts; Plant Leaves; Polycyclic Sesquiterpenes; Sesquiterpenes; Skin; Species Specificity

The essential oil composition of Feronia elephantum Correa (family: Rutaceae) was examined by capillary gas chromatography (GC) and gas chromatography-mass spectroscopy (GC-MS). The analysis revealed the presence of 24 constituents, of which 18 constituents were identified. Trans-anethole (57.73%) and methyl chavicol (37.48%) were the major compounds, while cis-anethole, p-anisaldehyde, (E)-jasmone, methyl eugenol, β-caryophyllene, linalool and (E)-methyl isoeugenol were also present as the minor constituents.

Topics: Acyclic Monoterpenes; Allylbenzene Derivatives; Anisoles; Benzaldehydes; Chromatography, Gas; Cyclopentanes; Eugenol; Gas Chromatography-Mass Spectrometry; Monoterpenes; Oils, Volatile; Oxylipins; Polycyclic Sesquiterpenes; Rutaceae; Sesquiterpenes

In laboratory experiments, we identified and quantified volatiles emitted by inflorescences and berries of two grape varieties (Trebbiano and Sangiovese) and examined the effects of the volatiles on oviposition by the grapevine moth Lobesia botrana. Compared to Trebbiano, Sangiovese is relatively more susceptible to L. botrana infestations under natural conditions. Chemical and electrophysiological analysis indicated only quantitative differences between the volatiles released by the two varieties. In a dual-choice oviposition bioassay based only on volatile cues, females did not show any preference between the two varieties. The six major components of the odor profiles that were GC-EAD-active to female antennae included: limonene, 4,8-dimethyl-1,(E)-3,7-nonatriene, (+/-)-linalool, (E)-caryophyllene, (E,E)-alpha-farnesene, and methyl salicylate. At the beginning of the berry touch phenological stage, their proportions were about 10:0.6:0.4:0.5:0.9:0.6 in Trebbiano and 10:1:0.4:1.5:0.4:0.3 in Sangiovese. A six-component synthetic lure (with the proportion 10:1:1:1:1:1, which approximated the ratio of components released by both varieties) was used in further laboratory oviposition bioassays. Depending on its dosage, the synthetic lure either attracted or repelled oviposition. L. botrana females laid significantly more eggs in the presence of either the grape bunches or the synthetic lure at the attractive dosage. In a release-capture experiment conducted in a field cage that covered two grapevine rows, the synthetic lure was more attractive than a grape cluster or a blank control, and it stimulated oviposition on the vegetation near the lure. The results indicate that L. botrana uses olfactory cues to select oviposition sites and that an artificial lure, containing the major volatiles released by two grape varieties, may be useful in monitoring female activity in the field.

Topics: Acyclic Monoterpenes; Animals; Behavior, Animal; Biological Assay; Cyclohexenes; Female; Larva; Limonene; Monoterpenes; Moths; Odorants; Oviposition; Polycyclic Sesquiterpenes; Sesquiterpenes; Terpenes; Vitis; Volatile Organic Compounds

This study is aimed to evaluate the in vitro cytotoxicity of Senecio stabianus Lacaita (Asteraceae) against renal adenocarcinoma ACHN, hormone-dependent prostate carcinoma LNCaP, amelanotic melanoma C32 and human breast adenocarcinoma MCF-7 cell lines. The n-hexane extract showed an interesting activity with IC(50) values of 62.7 and 71.1 microg mL(-1) against C32 and LNCaP, respectively. Two compounds identified in the n-hexane extract, linalool and beta-caryophyllene, were found to be active against C32 cells (IC(50) values of 23.2 and 20.1 microg mL(-1), respectively). Among tested constituents, the highest activity was found when alpha-humulene was applied to LNCaP cells (IC(50) of 11.2 microg mL(-1)). In order to complete the phytochemical study on S. stabianus, which has not been investigated previously, the most characteristic secondary metabolites of Senecio genus, pyrrolizidine alkaloids (PAs), were analysed. Here we report the isolation, structural elucidation and identification of nine PAs.

Topics: Acyclic Monoterpenes; Cell Line, Tumor; Cell Proliferation; Cell Survival; Gas Chromatography-Mass Spectrometry; Hexanes; Humans; Monocyclic Sesquiterpenes; Monoterpenes; Plant Extracts; Polycyclic Sesquiterpenes; Pyrrolizidine Alkaloids; Senecio; Sesquiterpenes

The essential oil in Michelia leaves was extracted by steam distillation. The oil obtained was dried with anhydrous magnesium sulfate. The chemical constituents were analyzed by GC-MS. Thirty three peaks were separated by GC, and 27 of them were identified by MS with NBS mass spectral data and Wiley/NBS registry of mass spectral data. The structure of linalool was further verified by GC/FTIR. The identified constituents represent 97% of the peak area of the essential oil on FID. The major chemical constituent of them are linalool, trans-caryophyllene and diethyl-o-phthalate.

Topics: Acyclic Monoterpenes; Gas Chromatography-Mass Spectrometry; Magnoliaceae; Monoterpenes; Oils, Volatile; Plant Leaves; Polycyclic Sesquiterpenes; Sesquiterpenes

The chemical constituents of the essential oils obtained from the leaves of Vitex negundo var. cannabifolia, V. negundo var. heterophylla, V. negundo and V. trifolia were analysed by GC-MS. Forty compounds including alpha-pinene, linalool, terpinyl acetate, beta-caryophyllene and caryophyllene oxide, etc. were identified. Their percentages in oils were given.

Topics: Acyclic Monoterpenes; Bicyclic Monoterpenes; Drugs, Chinese Herbal; Gas Chromatography-Mass Spectrometry; Monoterpenes; Oils, Volatile; Polycyclic Sesquiterpenes; Sesquiterpenes; Terpenes