Monoterpenes: Compounds with a core of 10 carbons generally formed via the mevalonate pathway from the combination of 3,3-dimethylallyl pyrophosphate and isopentenyl pyrophosphate. They are cyclized and oxidized in a variety of ways. Due to the low molecular weight many of them exist in the form of essential oils (OILS, VOLATILE).Terpenes: A class of compounds composed of repeating 5-carbon units of HEMITERPENES.Cyclohexenes: Six-carbon alicyclic hydrocarbons which contain one or more double bonds in the ring. The cyclohexadienes are not aromatic, in contrast to BENZOQUINONES which are sometimes called 2,5-cyclohexadiene-1,4-diones.Oils, Volatile: Oils which evaporate readily. The volatile oils occur in aromatic plants, to which they give odor and other characteristics. Most volatile oils consist of a mixture of two or more TERPENES or of a mixture of an eleoptene (the more volatile constituent of a volatile oil) with a stearopten (the more solid constituent). The synonym essential oils refers to the essence of a plant, as its perfume or scent, and not to its indispensability.Intramolecular Lyases: Enzymes of the isomerase class that catalyze reactions in which a group can be regarded as eliminated from one part of a molecule, leaving a double bond, while remaining covalently attached to the molecule. (From Enzyme Nomenclature, 1992) EC 5.5.Lavandula: A plant genus of the LAMIACEAE family.Thuja: A plant genus of the family CUPRESSACEAE.Polyisoprenyl Phosphates: Phosphoric or pyrophosphoric acid esters of polyisoprenoids.Hemiterpenes: The five-carbon building blocks of TERPENES that derive from MEVALONIC ACID or deoxyxylulose phosphate.Bicyclo CompoundsPentanes: Five-carbon saturated hydrocarbon group of the methane series. Include isomers and derivatives.Sesquiterpenes, Germacrane: SESQUITERPENES cyclized to one 10-carbon ring.Volatilization: A phase transition from liquid state to gas state, which is affected by Raoult's law. It can be accomplished by fractional distillation.Clarkia: A plant genus, of the family ONAGRACEAE, which is the subject of genetic studies. The floral aroma is attributed to benzenoid esters and benzyl acetate.Lamiaceae: The mint plant family. They are characteristically aromatic, and many of them are cultivated for their oils. Most have square stems, opposite leaves, and two-lipped, open-mouthed, tubular corollas (united petals), with five-lobed, bell-like calyxes (united sepals).Alkyl and Aryl Transferases: A somewhat heterogeneous class of enzymes that catalyze the transfer of alkyl or related groups (excluding methyl groups). EC 2.5.Mentha piperita: A plant genus of the family LAMIACEAE that is the source of peppermint oil.Thymol: A phenol obtained from thyme oil or other volatile oils used as a stabilizer in pharmaceutical preparations, and as an antiseptic (antibacterial or antifungal) agent. It was formerly used as a vermifuge.NorbornanesSesquiterpenesResins, Plant: Flammable, amorphous, vegetable products of secretion or disintegration, usually formed in special cavities of plants. They are generally insoluble in water and soluble in alcohol, carbon tetrachloride, ether, or volatile oils. They are fusible and have a conchoidal fracture. They are the oxidation or polymerization products of the terpenes, and are mixtures of aromatic acids and esters. Most are soft and sticky, but harden after exposure to cold. (From Grant & Hackh's Chemical Dictionary, 5th ed & Dorland, 28th ed)Wood: A product of hard secondary xylem composed of CELLULOSE, hemicellulose, and LIGNANS, that is under the bark of trees and shrubs. It is used in construction and as a source of CHARCOAL and many other products.Menthol: An alcohol produced from mint oils or prepared synthetically.Pinus sylvestris: A plant species of the genus PINUS which is the source of pinosylvin. It is sometimes called Scotch pine or Scots pine, which is also a common name for other species of this genus.Nitric Acid: Nitric acid (HNO3). A colorless liquid that is used in the manufacture of inorganic and organic nitrates and nitro compounds for fertilizers, dye intermediates, explosives, and many different organic chemicals. Continued exposure to vapor may cause chronic bronchitis; chemical pneumonitis may occur. (From Merck Index, 11th ed)Acaridae: Family of MITES, in the superfamily Acaroidea, order Astigmata. They are frequently found in cereal-based foodstuffs including GRAIN and FLOUR.Myrtus: A plant genus of the family MYRTACEAE. Members contain PHYTOHEMAGGLUTININS.Pinus: A plant genus in the family PINACEAE, order Pinales, class Pinopsida, division Coniferophyta. They are evergreen trees mainly in temperate climates.Illicium: A plant genus of the family Illiciaceae, order Illiciales, subclass Magnoliidae, class Magnoliopsida. They have evergreen, aromatic leaves and bisexual flowers. The female portion of the flower consists of 7 to 15 carpels.Gas Chromatography-Mass Spectrometry: A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.Camphor: A bicyclic monoterpene ketone found widely in plants, especially CINNAMOMUM CAMPHORA. It is used topically as a skin antipruritic and as an anti-infective agent.Dimethylallyltranstransferase: An enzyme that, in the pathway of cholesterol biosynthesis, catalyzes the condensation of isopentenyl pyrophosphate and dimethylallylpyrophosphate to yield pyrophosphate and geranylpyrophosphate. The enzyme then catalyzes the condensation of the latter compound with another molecule of isopentenyl pyrophosphate to yield pyrophosphate and farnesylpyrophosphate. EC 2.5.1.1.Beetles: INSECTS of the order Coleoptera, containing over 350,000 species in 150 families. They possess hard bodies and their mouthparts are adapted for chewing.Isomerases: A class of enzymes that catalyze geometric or structural changes within a molecule to form a single product. The reactions do not involve a net change in the concentrations of compounds other than the substrate and the product.(from Dorland, 28th ed) EC 5.Mevalonic AcidPlant Oils: Oils derived from plants or plant products.Diphosphates: Inorganic salts of phosphoric acid that contain two phosphate groups.Asteraceae: A large plant family of the order Asterales, subclass Asteridae, class Magnoliopsida. The family is also known as Compositae. Flower petals are joined near the base and stamens alternate with the corolla lobes. The common name of "daisy" refers to several genera of this family including Aster; CHRYSANTHEMUM; RUDBECKIA; TANACETUM.Plant Leaves: Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)Diterpenes: Twenty-carbon compounds derived from MEVALONIC ACID or deoxyxylulose phosphate.Stereoisomerism: The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Lovastatin: A fungal metabolite isolated from cultures of Aspergillus terreus. The compound is a potent anticholesteremic agent. It inhibits 3-hydroxy-3-methylglutaryl coenzyme A reductase (HYDROXYMETHYLGLUTARYL COA REDUCTASES), which is the rate-limiting enzyme in cholesterol biosynthesis. It also stimulates the production of low-density lipoprotein receptors in the liver.Plant Extracts: Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.Chromatography, Gas: Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Carbon-Carbon Double Bond Isomerases: Enzymes that catalyze the shifting of a carbon-carbon double bond from one position to another within the same molecule. EC 5.3.3.L-Iditol 2-Dehydrogenase: An alcohol oxidoreductase which catalyzes the oxidation of L-iditol to L-sorbose in the presence of NAD. It also acts on D-glucitol to form D-fructose. It also acts on other closely related sugar alcohols to form the corresponding sugar. EC 1.1.1.14Bronchitis: Inflammation of the large airways in the lung including any part of the BRONCHI, from the PRIMARY BRONCHI to the TERTIARY BRONCHI.TaiwanRetrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.Narcissus: A plant genus of the family LILIACEAE. Members contain ungiminorine and LECTINS.Galanthus: A plant genus in the family LILIACEAE (sometimes classified as Amaryllidaceae). Galanthus nivalis L. is the source of GALANTHAMINE.Amaranthaceae: A family of flowering plants in the order Caryophyllales, with about 60 genera and more than 800 species of plants, with a few shrubs, trees, and vines. The leaves usually have nonindented edges.Hydrocarbons

Prevention and therapy of cancer by dietary monoterpenes. (1/702)

Monoterpenes are nonnutritive dietary components found in the essential oils of citrus fruits and other plants. A number of these dietary monoterpenes have antitumor activity. For example, d-limonene, which comprises >90% of orange peel oil, has chemopreventive activity against rodent mammary, skin, liver, lung and forestomach cancers. Similarly, other dietary monoterpenes have chemopreventive activity against rat mammary, lung and forestomach cancers when fed during the initiation phase. In addition, perillyl alcohol has promotion phase chemopreventive activity against rat liver cancer, and geraniol has in vivo antitumor activity against murine leukemia cells. Perillyl alcohol and d-limonene also have chemotherapeutic activity against rodent mammary and pancreatic tumors. As a result, their cancer chemotherapeutic activities are under evaluation in Phase I clinical trials. Several mechanisms of action may account for the antitumor activities of monoterpenes. The blocking chemopreventive effects of limonene and other monoterpenes during the initiation phase of mammary carcinogenesis are likely due to the induction of Phase II carcinogen-metabolizing enzymes, resulting in carcinogen detoxification. The post-initiation phase, tumor suppressive chemopreventive activity of monoterpenes may be due to the induction of apoptosis and/or to inhibition of the post-translational isoprenylation of cell growth-regulating proteins. Chemotherapy of chemically induced mammary tumors with monoterpenes results in tumor redifferentiation concomitant with increased expression of the mannose-6-phosphate/insulin-like growth factor II receptor and transforming growth factor beta1. Thus, monoterpenes would appear to act through multiple mechanisms in the chemoprevention and chemotherapy of cancer.  (+info)

Activation of the transforming growth factor beta signaling pathway and induction of cytostasis and apoptosis in mammary carcinomas treated with the anticancer agent perillyl alcohol. (2/702)

The mechanisms of action of the anticancer agent perillyl alcohol (POH), presently in Phase II clinical trials, were investigated in advanced rat mammary carcinomas. Gross and ultrastructural morphology of POH-mediated tumor regression indicated that apoptosis accounted for the marked reduction in the epithelial compartment. Characterization of cell growth and death indices revealed that apoptosis was induced within 48 h of chemotherapy, before the induction of cytostasis. RNA expression studies, based on a multiplexed-nuclease protection assay, demonstrated that cell cycle- and apoptosis-related genes were differentially expressed within 48 h of POH treatment; p21(Cip1/WAF1), bax, bad, and annexin I were induced; cyclin E and cyclin-dependent kinase 2 were repressed; and bcl-2 and p53 were unchanged. Next, a potential role for transforming growth factor beta (TGF-beta) signaling in POH-mediated carcinoma regression was explored. RNA expression studies, again based on a multiplexed-nuclease protection assay, showed that TGF-beta-related genes were induced and temporally regulated during POH treatment: (a) c-jun and c-fos were transiently induced within 12 h of chemotherapy; (b) TGF-beta1 was induced within 24 h of chemotherapy; (c) the mannose 6-phosphate/insulin-like growth factor II receptor and the TGF-beta type I and II receptors were induced within 48 h of chemotherapy; and (d) smad3 was induced during active carcinoma regression. In situ protein expression studies, based on fluorescence-immunohistochemistry in concert with confocal microscopy, confirmed up-regulation and demonstrated colocalization of TGF-beta1, the mannose 6-phosphate/insulin-like growth factor II receptor, the TGF-beta type I and II receptors, and Smad2/Smad3 in epithelial cells. Nuclear localization of Smad2/Smad3 indicated that the TGF-beta signaling pathway was activated in regressing carcinomas. Subpopulations of Smad2/Smad3-positive and apoptotic nuclei colocalized, indicating a role for Smads in apoptosis. Thus, Smads may serve as a potential biomarker for anticancer activity. Importantly, none of the POH-mediated anticancer activities were observed in normal mammary gland.  (+info)

Metabolism of (R)-(+)-pulegone and (R)-(+)-menthofuran by human liver cytochrome P-450s: evidence for formation of a furan epoxide. (3/702)

(R)-(+)-Pulegone, a monoterpene constituent of pennyroyal oil, is a hepatotoxin that has been used in folklore medicine as an abortifacient despite its potential lethal effects. Pulegone is metabolized by human liver cytochrome P-450s to menthofuran, a proximate hepatotoxic metabolite of pulegone. Expressed human liver cytochrome (CYP) P-450s (1A2, 2A6, 2C9, 2C19, 2D6, 2E1, and 3A4) were tested for their ability to catalyze the oxidations of pulegone and menthofuran. Expressed CYP2E1, CYP1A2, and CYP2C19 oxidized pulegone to menthofuran, with respective Km and Vmax values of 29 microM and 8.4 nmol/min/nmol P-450 for CYP2E1, 94 microM and 2.4 nmol/min/nmol P-450 for CYP1A2, and 31 microM and 1.5 nmol/min/nmol P-450 for CYP2C19. The human liver P-450s involved in the metabolism of menthofuran are the same as pulegone except for the addition of CYP2A6. These P-450s were found to oxidize menthofuran to a newly identified metabolite, 2-hydroxymenthofuran, which is an intermediate in the formation of the known metabolites mintlactone and isomintlactone. Based on studies with 18O2 and H218O, 2-hydroxymenthofuran arises predominantly from a dihydrodiol formed from a furan epoxide. CYP2E1, CYP1A2, and CYP2C19 oxidized menthofuran with respective Km and Vmax values of 33 microM and 0.43 nmol/min/nmol P-450 for CYP2E1, 57 microM and 0.29 nmol/min/nmol P-450 for CYP1A2, and 62 microM and 0.26 nmol/min/nmol P-450 for CYP2C19.  (+info)

Olfactory discrimination ability of human subjects for ten pairs of enantiomers. (4/702)

We tested the ability of human subjects to distinguish between enantiomers, i.e. odorants which are identical except for chirality. In a forced-choice triangular test procedure 20 subjects were repeatedly presented with 10 enantiomeric odor pairs and asked to identify the bottle containing the odd stimulus. We found (i) that as a group, the subjects were only able to significantly discriminate the optical isomers of alpha-pinene, carvone and limonene, whereas they failed to distinguish between the (+)- and (-)-forms of menthol, fenchone, rose oxide, camphor, alpha-terpineol, beta-citronellol and 2-butanol; (ii) marked individual differences in discrimination performance, ranging from subjects who were able to significantly discriminate between 6 of the 10 odor pairs to subjects who failed to do so with 9 of the 10 tasks; (iii) that with none of the 10 odor pairs were the antipodes reported to differ significantly in subjective intensity when presented at equal concentrations; and (iv) that error rates were quite stable and did not differ significantly between sessions, and thus, we observed a lack of learning or training effects. Additional tests of the degree of trigeminality and threshold measurements of the optical isomers of alpha-pinene, carvone and limonene suggest that the discriminability of these three enantiomeric odor pairs is indeed due to differences in odor quality. These findings support the assumption that enantioselective molecular odor receptors may only exist for some but not all volatile enantiomers and thus that chiral recognition of odorants may not be a general phenomenon but is restricted to some substances.  (+info)

Identification and sequencing of beta-myrcene catabolism genes from Pseudomonas sp. strain M1. (5/702)

The M1 strain, able to grow on beta-myrcene as the sole carbon and energy source, was isolated by an enrichment culture and identified as a Pseudomonas sp. One beta-myrcene-negative mutant, called N22, obtained by transposon mutagenesis, accumulated (E)-2-methyl-6-methylen-2,7-octadien-1-ol (or myrcen-8-ol) as a unique beta-myrcene biotransformation product. This compound was identified by gas chromatography-mass spectrometry. We cloned and sequenced the DNA regions flanking the transposon and used these fragments to identify the M1 genomic library clones containing the wild-type copy of the interrupted gene. One of the selected cosmids, containing a 22-kb genomic insert, was able to complement the N22 mutant for growth on beta-myrcene. A 5,370-bp-long sequence spanning the region interrupted by the transposon in the mutant was determined. We identified four open reading frames, named myrA, myrB, myrC, and myrD, which can potentially code for an aldehyde dehydrogenase, an alcohol dehydrogenase, an acyl-coenzyme A (CoA) synthetase, and an enoyl-CoA hydratase, respectively. myrA, myrB, and myrC are likely organized in an operon, since they are separated by only 19 and 36 nucleotides (nt), respectively, and no promoter-like sequences have been found in these regions. The myrD gene starts 224 nt upstream of myrA and is divergently transcribed. The myrB sequence was found to be completely identical to the one flanking the transposon in the mutant. Therefore, we could ascertain that the transposon had been inserted inside the myrB gene, in complete agreement with the accumulation of (E)-2-methyl-6-methylen-2,7-octadien-1-ol by the mutant. Based on sequence and biotransformation data, we propose a pathway for beta-myrcene catabolism in Pseudomonas sp. strain M1.  (+info)

Mechanism of inhibition of aldehyde dehydrogenase by citral, a retinoid antagonist. (6/702)

Low concentrations of citral (3,7-dimethyl-2,6-octadienal), an inhibitor of retinoic acid biosynthesis, inhibited E1, E2 and E3 isozymes of human aldehyde dehydrogenase (EC1.2.1.3). The inhibition was reversible on dilution and upon long incubation in the presence of NAD+; it occurred with simultaneous formation of NADH and of geranic acid. Thus, citral is an inhibitor and also a substrate. Km values for citral were 4 microM for E1, 1 microM for E2 and 0.1 microM for E3; Vmax values were highest for E1 (73 nmol x min-1 x mg-1), intermediate for E2 (17 nmol x min-1 x mg-1) and lowest (0.07 nmol x min-1 x mg-1) for the E3 isozyme. Citral is a 1 : 2 mixture of isomers: cis isomer neral and trans isomer, geranial; the latter structurally resembles physiologically important retinoids. Both were utilized by all three isozymes; a preference for the trans isomer, geranial, was observed by HPLC and by enzyme kinetics. With the E1 isozyme, both geranial and neral, and with the E2 isozyme, only neral obeyed Michaelis-Menten kinetics. With the E2 isozyme and geranial sigmoidal saturation curves were observed with S0.5 of approximately 50 nM; the n-values of 2-2.5 indicated positive cooperativity. Geranial was a better substrate and a better inhibitor than neral. The low Vmax, which appeared to be controlled by either the slow formation, or decomposition via the hydride transfer, of the thiohemiacetal reaction intermediate, makes citral an excellent inhibitor whose selectivity is enhanced by low Km values. The Vmax for citral with the E1 isozyme was higher than those of the E2 and E3 isozymes which explains its fast recovery following inhibition by citral and suggests that E1 may be the enzyme involved in vivo citral metabolism.  (+info)

The branched-chain dodecylbenzene sulfonate degradation pathway of Pseudomonas aeruginosa W51D involves a novel route for degradation of the surfactant lateral alkyl chain. (7/702)

Pseudomonas aeruginosa W51D is able to grow by using branched-chain dodecylbenzene sulfonates (B-DBS) or the terpenic alcohol citronellol as a sole source of carbon. A mutant derived from this strain (W51M1) is unable to degrade citronellol but still grows on B-DBS, showing that the citronellol degradation route is not the main pathway involved in the degradation of the surfactant alkyl moiety. The structures of the main B-DBS isomers and of some intermediates were identified by gas chromatography-mass spectrometric analysis, and a possible catabolic route is proposed.  (+info)

p53 induction as a genotoxic test for twenty-five chemicals undergoing in vivo carcinogenicity testing. (8/702)

In vivo carcinogenicity testing is an expensive and time-consuming process, and as a result, only a relatively small fraction of new and existing chemicals has been tested in this manner. Therefore, the development and validation of alternative approaches is desirable. We previously developed a mammalian in vitro assay for genotoxicity based on the ability of cells to increase their level of the tumor-suppressor protein p53 in response to DNA damage. Cultured cells are treated with various amounts of the test substances, and at defined times following treatment, they are harvested and lysed. The lysates are analyzed for p53 by Western blot and/or enzyme-linked immunosorbent assay analysis. An increase in cellular p53 following treatment is interpreted as evidence for DNA damage. To determine the ability of this p53-induction assay to predict carcinogenicity in rodents and to compare such results with those obtained using alternate approaches, we subjected 25 chemicals from the predictive toxicology evaluation 2 list to analysis with this method. Five substances (citral, cobalt sulfate heptahydrate, D&C Yellow No. 11, oxymetholone, and t-butylhydroquinone) tested positive in this assay, and three substances (emodin, phenolphthalein, and sodium xylenesulfonate) tested as possibly positive. Comparisons between the results obtained with this assay and those obtained with the in vivo protocol, the Salmonella assay, and the Syrian hamster embryo (SHE) cell assay indicate that the p53-induction assay is an excellent predictor of the limited number of genotoxic carcinogens in this set, and that its accuracy is roughly equivalent to or better than the Salmonella and SHE assays for the complete set of chemicals.  (+info)

  • The ability of secondary organic aerosol (SOA) produced from the ozonolysis of α-pinene and monoterpene mixtures (α-pinene, β-pinene, limonene and 3-carene) to become cloud droplets was investigated. (atmos-chem-phys.net)
  • Monoterpenes are a class of terpenes that consist of two isoprene units and have the molecular formula C10H16. (wikipedia.org)
  • Formation of organic nitrates (RONO2) during oxidation of biogenic volatile organic compounds (BVOCs: isoprene, monoterpenes) is a significant loss pathway for atmospheric nitrogen oxide radicals (NOx), but the chemistry of RONO2 formation and degradation remains uncertain. (nasa.gov)
  • Here we implement a new BVOC oxidation mechanism (including updated isoprene chemistry, new monoterpene chemistry, and particle uptake of RONO2) in the GEOS-Chem global chemical transport model with ∼ 25 × 25 km2 resolution over North America. (nasa.gov)
  • Gas-phase isoprene nitrates account for 25-50 % of observed RONO2 in surface air, and we find that another 10 % is contributed by gas-phase monoterpene nitrates. (nasa.gov)
  • Monoterpenes are formed by the condensation of two isoprene molecules. (aacrjournals.org)
  • They can be classified on the basis of value of n or number of carbon atoms present in the structure into hemiterpene (C5), monoterpenes (C10), sesquiterpene (C15), diterpenes (C20), sesterpens (C25), triterpenes (C30), tetraterpens (C40), polyterpenes (>40C). (nsk.hr)
  • Geranyl pyrophosphate can also undergo two sequential cyclization reactions to form bicyclic monoterpenes, such as pinene which is the primary constituent of pine resin. (wikipedia.org)
  • Na temelju broja n u općoj formuli (C5H8)n ili broja C atoma terpeni se dijele na hemiterpene (C5), monoterpene (C10), sesquiterpene (C15), diterpene (C20), sesterpeni (C25), triterpeni (C30), tetraterpeni (C40), politerpeni (>C 40). (nsk.hr)
  • Monoterpenes are emitted by forests and form aerosols that can serve as cloud condensation nuclei (CCN). (wikipedia.org)
  • The interaction between the monoterpenes and lipid bilayers is considered important to the understanding of the biological functions of monoterpenes. (lu.se)
  • The investigation included personal air sampling of monoterpenes, biological monitoring of metabolites of I-pinene in the workers' urine, interviews following a standardized questionnaire, and dynamic spirometry. (sjweh.fi)
  • Conclusions Personal exposure to the monoterpenes I-pinene, J-pinene, and q3-carene in joinery shops may exceed the present Swedish occupational exposure limit of 150 mg/m3 during the winter season when workroom air is commonly recirculated. (sjweh.fi)
  • The CCN activation diameter of α-pinene and mixed monoterpene SOA can be modelled to within 10-15% of experiments by a simple implementation of Köhler theory, assuming complete dissolution of the particles, no dissociation into ions, a molecular weight of 180 g mol −1 , a density of 1.5 g cm −3 , and the surface tension of water. (atmos-chem-phys.net)
  • Cyclic and linear monoterpenes in phospholipid membranes: Phase behavior, bilayer structure, and molecular dynamics. (lu.se)
  • Oxidation of 1,8-cineole, the monoterpene cyclic ether originated from eucalyptus polybractea, by cytochrome P450 3A enzymes in rat and human liver microsomes. (uniprot.org)
  • Selected monoterpenes inhibited methane oxidation by methanotrophs ( Methylosinus trichosporium OB3b, Methylobacter luteus ), denitrification by environmental isolates, and aerobic metabolism by several heterotrophic pure cultures. (asm.org)
  • Oxidation of monoterpenes catalysed b. (ugent.be)
  • Monoterpene synthases of loblolly pine (Pinus taeda) produce pinene isomers and enantiomers. (nih.gov)
  • Cell-free extracts from xylem tissue yielded three monoterpene synthases which together account for the monoterpene isomer and enantiomer content of the turpentine of this tissue. (nih.gov)
  • In most properties (molecular mass of approximately 60 kDa, K(m) for geranyl diphosphate of 3 microM, requirement for monovalent and divalent cations), these enzymes resemble other monoterpene synthases from conifer species. (nih.gov)
  • A proposed universal monoterpene synthases (cyclases) cyclization mechanism topologically requires an isomerization step of the substrate geranyl diphosphate (GPP) to the formation of the proposed universal intermediate linalyl diphosphate (LPP), which has never been directly observed. (brandeis.edu)
  • The oil contains predominantly monoterpenes and related alcohols, and its composition is regulated by the international standard ISO 4730:2004 ( 20 ). (asm.org)
  • Here, we developed and applied membrane inlet mass spectrometry (MIMS) with a simple sampling probe for an on-site determination of the most common monoterpenes and monoterpene alcohols in the forest soil atmosphere. (vtt.fi)
  • Geranyl pyrophosphate can also undergo two sequential cyclization reactions to form bicyclic monoterpenes, such as pinene which is the primary constituent of pine resin. (wikipedia.org)
  • The major products of these enzymes, produced from the universal precursor of monoterpenes, geranyl diphosphate, were shown to be (+)-alpha-pinene, (-)-alpha-pinene, and (-)-beta-pinene, respectively. (nih.gov)
  • Headspace exposure of Arabidopsis thaliana to a mixture of the bicyclic monoterpenes α-pinene and β-pinene induced defense, accumulation of reactive oxygen species, and expression of SA - and SAR-related genes, including the SAR regulatory AZELAIC ACID INDUCED1 ( AZI1 ) gene and three of its paralogs. (plantcell.org)
  • The CCN activation diameter of α-pinene and mixed monoterpene SOA can be modelled to within 10-15% of experiments by a simple implementation of Köhler theory, assuming complete dissolution of the particles, no dissociation into ions, a molecular weight of 180 g mol −1 , a density of 1.5 g cm −3 , and the surface tension of water. (atmos-chem-phys.net)
  • Pinene is a very useful monoterpene that is found in pine resins, and various resins from other plants, trees and herbs. (apollyon.nl)
  • The Vanderwal group at the University of California Irvine aims to develop the first synthesis of members of the Plocamium polyhalogenated monoterpenes, The proposed synthesis is concise and modular, allowing for multiple members of the class to be synthesized, as well as a host of unnatural analogues, with only minor modifications to the procedure. (grantome.com)
  • Initial results on the synthesis of simplified model systems are promising, and once completed, the Plocamium polyhalogenated monoterpene natural products will be synthesized. (grantome.com)
  • Total monoterpene concentration was negatively related to foliar nitrogen concentration, suggesting that C/N balance may affect monoterpene synthesis in needles. (elsevier.com)
  • Deciphering the route to cyclic monoterpenes in Chrysomelina leaf beetles: source of new biocatalysts for industrial application? (degruyter.com)
  • 1,8-Cineole, the monoterpene cyclic ether known as eucalyptol, is one of the components in essential oils from Eucalyptus polybractea. (uniprot.org)
  • Cyclic and linear monoterpenes in phospholipid membranes: Phase behavior, bilayer structure, and molecular dynamics. (lu.se)
  • Home Research Outputs Cyclic and linear monoterpenes in phospholipid membranes: Ph. (lu.se)
  • In this study we investigate the effect of cyclic and linear monoterpenes on the structure and dynamics of lipids in model membrane. (lu.se)
  • The normalised monoterpene emission rates (leaf temperature 30°C) of these Eucalyptus species ranged from zero for E. forrestiana to 5.4±2.2 μg g−1 h−1 (or 871±33 μg m−2 h−1) for E. globulus. (edu.au)
  • Here, we investigated emissions of monoterpenes, isoprene and DMS as well as seasonal carbon assimilation from four big-leaf mahogany trees in their natural outdoor environment using a dynamic branch cuvette system, high-sensitivity proton transfer reaction mass spectrometer and cavity ring-down spectrometer. (atmos-chem-phys.net)
  • We show that the importance of considering the enhanced monoterpene emission potential of new Scots pine foliage decreases as a function of season, tree age and latitude, and that new foliage is responsible for the majority of the whole tree's foliage emissions of monoterpenes during spring time, independently of tree age and location. (copernicus.org)
  • Likewise, simulated growth rates of 2-3 nm particles would increase by ~ 65-175 % in northern Finland and by ~ 110-520 % in southern Finland if the enhanced emissions of monoterpenes from new Scots pine foliage were explicitly considered. (copernicus.org)
  • One as yet largely unexplored process is the effect of nutrient availability on monoterpene emission. (open.ac.uk)
  • In this study we treated young Scots pine seedlings with fertilizer (NPK and urea) largely and observed a large increase in monoterpene emission compared with unfertilized controls. (open.ac.uk)
  • These results are important for understanding future trends in monoterpene emission, since nitrogen deposition, as consequence of industrial emissions and agricultural sources, is increasing in the soils of boreal and high altitude temperate forests. (open.ac.uk)
  • Using the measured seasonal emission fluxes, we provide the first estimates for the global emissions from mahogany trees which amount to circa 210-320 Gg yr −1 for monoterpenes, 370-550 Mg yr −1 for DMS and 1700-2600 Mg yr −1 for isoprene. (atmos-chem-phys.net)
  • Detailed regional measurements and model estimates are needed to study emission potential and the monoterpene budget on a global scale. (biogeosciences.net)
  • For the first time, the emission models included seasonal and diurnal variations in both quantity and chemical species of emitted monoterpenes, based on parameterizations obtained from field measurements. (biogeosciences.net)
  • Monoterpene and isoprene emission rates of 15 Eucalyptus species were measured using an air exchange chamber technique and GC-FID analysis. (edu.au)
  • Based on monoterpene emission rate data from four Eucalyptus species (E. globulus, E. robusta, E. rudis, and E. sargentii), there were clear exponential relationships between leaf temperature and monoterpene emission rate for these Eucalyptus species. (edu.au)
  • Our results suggest that annual monoterpene emission estimates from Finland would increase with up to ~ 25 % if the emissions from new Scots pine foliage were explicitly considered, with the majority being emitted during spring time where also new particle formation has been observed to occur most frequently. (copernicus.org)
  • In addition, monoterpenes are not water-soluble and should not be used in the bath unless well-diluted with a carrier oil or base. (aromahut.com)
  • The fumigant effect was evaluated by exposing larvae to vapour from 100 µl of pure monoterpene in a sealed container. (eje.cz)
  • For those applications, oils with high monoterpene percentages (but a low alpha-humulene or caryophyllene oxide concentration) are desirable. (wikipedia.org)
  • Fractional composition of different monoterpenes was similar between different years and between clones and mature trees, indicating genetic control of this trait. (elsevier.com)
  • In particular, because blends of two or more monoterpenes will act as better synergists for attractive mountain pine beetle pheromones than any monoterpene used alone, more beetles will be attracted to the composition, and management of infestations will be improved. (freepatentsonline.com)
  • Over 400 trees of Abies lasiocarpa from fifty localities covering its entire range have been examined for composition of the cortical monoterpenes. (eurekamag.com)
  • The monoterpene, and particularly the sesquiterpene composition of olive oil may be used to distinguish samples from different cultivar and geographical areas. (csic.es)
  • We also found that monoterpene profiles of wines derived from mixed fermentations were found to be determined by the composition of the initial yeast inocula suggesting the feasibility of producing 'à la carte' wines having predetermined monoterpene contents. (biomedcentral.com)
  • Monoterpenes may be linear (acyclic) or contain rings. (wikipedia.org)
  • Elimination of the pyrophosphate group leads to the formation of acyclic monoterpenes such as ocimene and the myrcenes. (wikipedia.org)
  • Apoptosis-Inducing costunolide and a novel acyclic monoterpene from the stem bark of Magnolia sieboldii. (semanticscholar.org)
  • In a course of obtaining more amount of bioactive costunolide and successive phytochemical isolation from Magnolia sieboldii (Magnoliaceae), a novel acyclic monoterpene 1 named deoxygeraniol [2,6(E)-dimethyl-2,6-octadiene] was isolated along with beta-sitosterol 3-O-linoleate (2), trilinolein (3) and high amount of costunolide (4) in the pure state. (semanticscholar.org)
  • Besides creating a pungent odor, monoterpenes also play a key role in protecting the plant from fungal infections, certain strains of bacteria, and insects. (maximumyield.com)
  • Recently, it has been suggested that monoterpenes play an important role in altering nitrogen (N) and carbon (C) cycling in forest soils ( 36 ). (asm.org)
  • Monoterpenes, naturally-occurring hydrocarbon molecules that are low in toxicity, may help fill this gap. (prweb.com)
  • Although this correlates closely with a decrease in monoterpene accumulation, the latter may also be the result of competition with other pathways for substrate. (plantphysiol.org)
  • The turpentine fraction of conifer oleoresin is a complex mixture of monoterpene olefins and plays important roles in defense and in the mediation of chemical communication between conifer hosts and insect predators. (nih.gov)
  • Monoterpenes (C 10 H 16 ) are the products of metabolism found in many plants and are most notably emitted by conifers. (open.ac.uk)
  • Monoterpenes have been shown to contribute to aerosol and cloud formation, which have a net cooling effect on Earth's radiative balance. (open.ac.uk)
  • Thus, we build on these discoveries and investigate the impact of previously neglecting enhanced emissions from new Scots pine foliage on estimates of monoterpene emissions and new atmospheric aerosol particle formation and their subsequent growth. (copernicus.org)
  • Considering that monoterpenes are common in many plant species and are used in cosmetic and pharmaceutical preparations, as well as the food industry, it is important to review the pharmacological potential of monoterpenes with anticancer activity. (hindawi.com)
  • The degree of inhibition was monoterpene and species dependent. (asm.org)
  • Monoterpenes affected the attraction of three sympatric species of bark beetles (Coleoptera: Scolytidae) to pheromone-baited multiple-funnel traps in stands of lodgepole pine. (usda.gov)
  • In recent years, scientists have become increasingly interested in monoterpenes because they are capable of scavenging 'reactive oxygen species' (ROS) in the body. (prweb.com)
  • Plocamium polyhalogenated monoterpenes are metabolites first isolated from the red algae Plocamium cartilagineum, featuring several units of unsaturation, as well as multiple halogens, including two contiguous stereogenic chlorine-bearing carbons. (grantome.com)
  • Cytotoxic halogenated monoterpenes from Plocamium cartilagineum" by Omar MM Sabry, Douglas E. Goeger et al. (henryford.com)
  • The monoterpene spray also significantly inhibited ABA accumulation under severe stress, possibly by interfering with the methylerythritol (MEP) pathway and thereby reducing production of ABA precursors. (lancs.ac.uk)
  • We concluded that expression of differences in budworm resistance among Douglas fir genotypes might be caused by interactions among multiple resistance mechanisms such as needle monoterpenes and tree budburst phenology. (elsevier.com)
  • Certain monoterpenes produced by aromatic plants are known to have lethal and sublethal effects on insects. (eje.cz)
Α-Curcumene Profile | Monoterpenes | Eybna Technologies
Α-Curcumene Profile | Monoterpenes | Eybna Technologies (eybna.com)
Molecules  | Free Full-Text | Medically Useful Plant Terpenoids: Biosynthesis, Occurrence, and Mechanism of Action | HTML
Molecules | Free Full-Text | Medically Useful Plant Terpenoids: Biosynthesis, Occurrence, and Mechanism of Action | HTML (mdpi.com)
Antitumor Activity of Monoterpenes Found in Essential Oils
Antitumor Activity of Monoterpenes Found in Essential Oils (hindawi.com)
Phytochemicals | MindMeister Mind Map
Phytochemicals | MindMeister Mind Map (mindmeister.com)
Joseph T. Hodges | NIST
Joseph T. Hodges | NIST (nist.gov)
Cannabis flower essential oil - Wikipedia
Cannabis flower essential oil - Wikipedia (en.wikipedia.org)
Journal of Experimental Biology
Journal of Experimental Biology (jeb.biologists.org)
COPD Remedies Can Be Effective With Natural Cures - Natural Home Remedies
COPD Remedies Can Be Effective With Natural Cures - Natural Home Remedies (natural-homeremedies.com)
What are Monoterpenes? - Definition from Maxyield
What are Monoterpenes? - Definition from Maxyield (maximumyield.com)
Pseudoionone | chemical compound | Britannica
Pseudoionone | chemical compound | Britannica (britannica.com)
Citral | chemical compound | Britannica.com
Citral | chemical compound | Britannica.com (britannica.com)
Molecules | Free Full-Text | Germacrene D, A Common Sesquiterpene in the Genus Bursera (Burseraceae)
Molecules | Free Full-Text | Germacrene D, A Common Sesquiterpene in the Genus Bursera (Burseraceae) (mdpi.com)
Molecules  | Free Full-Text | GC-MS and HS-SPME-GC×GC-TOFMS Determination of the Volatile Composition of Essential Oils and...
Molecules | Free Full-Text | GC-MS and HS-SPME-GC×GC-TOFMS Determination of the Volatile Composition of Essential Oils and... (mdpi.com)
Airborne Monoterpenes Emitted from a Cupressus lusitanica Cell Culture Induce a Signaling Cascade that Produces β-Thujaplicin |...
Airborne Monoterpenes Emitted from a Cupressus lusitanica Cell Culture Induce a Signaling Cascade that Produces β-Thujaplicin |... (link.springer.com)
Molecules  | Free Full-Text | Antifungal Activity of Thapsia villosa Essential Oil against Candida, Cryptococcus, Malassezia,...
Molecules | Free Full-Text | Antifungal Activity of Thapsia villosa Essential Oil against Candida, Cryptococcus, Malassezia,... (mdpi.com)
Toxicity of Monoterpene Structure, Diversity and Concentration to Mountain Pine Beetles, Dendroctonus ponderosae : Beetle...
Toxicity of Monoterpene Structure, Diversity and Concentration to Mountain Pine Beetles, Dendroctonus ponderosae : Beetle... (link.springer.com)
Dietary Phytochemicals in Cancer Prevention and Treatment | SpringerLink
Dietary Phytochemicals in Cancer Prevention and Treatment | SpringerLink (link.springer.com)
Some Common Spices and Plants with Antimicrobial and Therapeutic
Properties
Some Common Spices and Plants with Antimicrobial and Therapeutic Properties (www2.hawaii.edu/~johnb/)
Supercritical fluid extraction as a tool for isolation of monoterpenes from coniferous needles and walnut-tree leaves |...
Supercritical fluid extraction as a tool for isolation of monoterpenes from coniferous needles and walnut-tree leaves |... (link.springer.com)
Antinociceptive Activity and Redox Profile of the Monoterpenes (+)-Camphene, p-Cymene, and Geranyl Acetate in Experimental...
Antinociceptive Activity and Redox Profile of the Monoterpenes (+)-Camphene, p-Cymene, and Geranyl Acetate in Experimental... (hindawi.com)
Herbs, Spices, and Medicinal Plants: Recent Advances in Botany, Horticulture ... - Google Books
Herbs, Spices, and Medicinal Plants: Recent Advances in Botany, Horticulture ... - Google Books (books.google.com)
Frontiers | Natural Carbon Isotope Composition Distinguishes Compound Groups of Biogenic Volatile Organic Compounds (BVOC) in...
Frontiers | Natural Carbon Isotope Composition Distinguishes Compound Groups of Biogenic Volatile Organic Compounds (BVOC) in... (frontiersin.org)
Reproductive Toxicants and Induced Abortions Flashcards by Lindsay Patterson | Brainscape
Reproductive Toxicants and Induced Abortions Flashcards by Lindsay Patterson | Brainscape (brainscape.com)
Argan oil components
Argan oil components (botanical-online.com)
Palmarosa Essential Oil - Pure Organic Palmarosa Oil
Palmarosa Essential Oil - Pure Organic Palmarosa Oil (anandaapothecary.com)
Where Antioxidants Are Found - Foods With Antioxidants | HowStuffWorks
Where Antioxidants Are Found - Foods With Antioxidants | HowStuffWorks (health.howstuffworks.com)
Pure Carrot Seed Oil - Organic Carrot Seed Essential Oil
Pure Carrot Seed Oil - Organic Carrot Seed Essential Oil (anandaapothecary.com)
Gum of Cistus ladaniferus (Cistaceae) obtained... - Registration Dossier - ECHA
Gum of Cistus ladaniferus (Cistaceae) obtained... - Registration Dossier - ECHA (echa.europa.eu)
Dolichoderinae
Dolichoderinae (tolweb.org)