Showing papers on "Terpene published in 2007"
TL;DR: Dehydroisomerization of Limonene and Terpenes To Produce Cymene 2481 4.2.1.
Abstract: 3.2.3. Hydroformylation 2467 3.2.4. Dimerization 2468 3.2.5. Oxidative Cleavage and Ozonolysis 2469 3.2.6. Metathesis 2470 4. Terpenes 2472 4.1. Pinene 2472 4.1.1. Isomerization: R-Pinene 2472 4.1.2. Epoxidation of R-Pinene 2475 4.1.3. Isomerization of R-Pinene Oxide 2477 4.1.4. Hydration of R-Pinene: R-Terpineol 2478 4.1.5. Dehydroisomerization 2479 4.2. Limonene 2480 4.2.1. Isomerization 2480 4.2.2. Epoxidation: Limonene Oxide 2480 4.2.3. Isomerization of Limonene Oxide 2481 4.2.4. Dehydroisomerization of Limonene and Terpenes To Produce Cymene 2481
5,127 citations
TL;DR: This review mainly summarizes the recent research progress in elucidating the ecological role of terpenoids and characterization of the enzymes involved in the terpenoid biosynthesis.
Abstract: Among plant secondary metabolites terpenoids are a structurally most diverse group; they function as phytoalex- ins in plant direct defense, or as signals in indirect defense responses which involves herbivores and their natural enemies. In recent years, more and more attention has been paid to the investigation of the ecological role of plant terpenoids. The biosynthesis pathways of monoterpenes, sesquiterpenes, and diterpenes include the synthesis of C5 precursor isopentenyl diphosphate (IPP) and its allylic isomer dimethylallyl diphosphate (DMAPP), the synthe- sis of the immediate diphosphate precursors, and the formation of the diverse terpenoids. Terpene synthases (TPSs) play a key role in volatile terpene synthesis. By expression of the TPS genes, significant achievements have been made on metabolic engineering to increase terpenoid production. This review mainly summarizes the recent research progress in elucidating the ecological role of terpenoids and characterization of the enzymes involved in the terpenoid biosynthesis. Spatial and temporal regulations of terpenoids metabolism are also discussed.
375 citations
TL;DR: The major conclusion is that larger-scale use of terpenoids in modern medicine should be taken into consideration.
Abstract: Terpenes are naturally occurring substances produced by a wide variety of plants and animals. A broad range of the biological properties of terpenoids is described, including cancer chemopreventive effects, antimicrobial, antifungal, antiviral, antihyperglycemic, anti-inflammatory, and antiparasitic activities. Terpenes are also presented as skin penetration enhancers and agents involved in the prevention and therapy of several inflammatory diseases. Moreover, a potential mechanism of their action against pathogens and their influence on skin permeability are discussed. The major conclusion is that larger-scale use of terpenoids in modern medicine should be taken into consideration.
332 citations
TL;DR: In this article, the authors proposed a dehydroisomerization of R-Pinene and terpenes to produce Cymene, which was shown to be more efficient than the traditional dehydration.
Abstract: 3.2.3. Hydroformylation 2467 3.2.4. Dimerization 2468 3.2.5. Oxidative Cleavage and Ozonolysis 2469 3.2.6. Metathesis 2470 4. Terpenes 2472 4.1. Pinene 2472 4.1.1. Isomerization: R-Pinene 2472 4.1.2. Epoxidation of R-Pinene 2475 4.1.3. Isomerization of R-Pinene Oxide 2477 4.1.4. Hydration of R-Pinene: R-Terpineol 2478 4.1.5. Dehydroisomerization 2479 4.2. Limonene 2480 4.2.1. Isomerization 2480 4.2.2. Epoxidation: Limonene Oxide 2480 4.2.3. Isomerization of Limonene Oxide 2481 4.2.4. Dehydroisomerization of Limonene and Terpenes To Produce Cymene 2481
264 citations
TL;DR: The results underline the importance of trichomes in JA-induced terpene emission in tomato and propose that LeMTS1 is a genuine linalool synthase.
Abstract: Tomato (Lycopersicon esculentum) plants emit a blend of volatile organic compounds, which mainly consists of terpenes. Upon herbivory or wounding, the emission of several terpenes increases. We have identified and characterized the first two tomato monoterpene synthases, LeMTS1 and LeMTS2. Although these proteins were highly homologous, recombinant LeMTS1 protein produced (R)-linalool from geranyl diphosphate (GPP) and (E)-nerolidol from farnesyl diphosphate (FPP), while recombinant LeMTS2 produced β-phellandrene, β-myrcene, and sabinene from GPP. In addition, these genes were expressed in different tissues: LeMTS1 was expressed in flowers, young leaves, stems, and petioles, while LeMTS2 was strongest expressed in stems and roots. LeMTS1 expression in leaves was induced by spider mite-infestation, wounding and jasmonic acid (JA)-treatment, while LeMTS2 did not respond to these stimuli. The expression of LeMTS1 in stems and petioles was predominantly detected in trichomes and could be induced by JA. Because JA treatment strongly induced emission of linalool and overexpression of LeMTS1 in tomato resulted in increased production of linalool, we propose that LeMTS1 is a genuine linalool synthase. Our results underline the importance of trichomes in JA-induced terpene emission in tomato.
226 citations
TL;DR: Elucidation of the structure of 1,8-cineole synthase from Salvia fruticosa (Sf-CinS1) combined with analysis of functional and phylogenetic relationships of enzymes within Salvia species identified active-site residues responsible for product specificity.
Abstract: Terpene synthases are responsible for the biosynthesis of the complex chemical defense arsenal of plants and microorganisms. How do these enzymes, which all appear to share a common terpene synthase fold, specify the many different products made almost entirely from one of only three substrates? Elucidation of the structure of 1,8-cineole synthase from Salvia fruticosa (Sf-CinS1) combined with analysis of functional and phylogenetic relationships of enzymes within Salvia species identified active-site residues responsible for product specificity. Thus, Sf-CinS1 was successfully converted to a sabinene synthase with a minimum number of rationally predicted substitutions, while identification of the Asn side chain essential for water activation introduced 1,8-cineole and α-terpineol activity to Salvia pomifera sabinene synthase. A major contribution to product specificity in Sf-CinS1 appears to come from a local deformation within one of the helices forming the active site. This deformation is observed in all other mono- or sesquiterpene structures available, pointing to a conserved mechanism. Moreover, a single amino acid substitution enlarged the active-site cavity enough to accommodate the larger farnesyl pyrophosphate substrate and led to the efficient synthesis of sesquiterpenes, while alternate single substitutions of this critical amino acid yielded five additional terpene synthases.
215 citations
TL;DR: It is demonstrated that OsTPS3, an enzyme catalyzing the formation of volatile sesquiterpenes, plays a role in indirect defense of rice plants.
195 citations
TL;DR: These yeast now provide a convenient format for investigating catalytic coupling between terpene synthases and hydroxylases, as well as a platform for the industrial production of high value, single‐entity and stereochemically unique terpenes.
Abstract: Terpenes are structurally diverse compounds that are of interest because of their biological activities and industrial value. These compounds consist of chirally rich hydrocarbon backbones derived from terpene synthases, which are subsequently decorated with hydroxyl substituents catalyzed by terpene hydroxylases. Availability of these compounds is, however, limited by intractable synthetic means and because they are produced in low amounts and as complex mixtures by natural sources. We engineered yeast for sesquiterpene accumulation by introducing genetic modifications that enable the yeast to accumulate high levels of the key intermediate farnesyl diphosphate (FPP). Co-expression of terpene synthase genes diverted the enlarged FPP pool to greater than 80 mg/L of sesquiterpene. Efficient coupling of terpene production with hydroxylation was also demonstrated by coordinate expression of terpene hydroxylase activity, yielding 50 mg/L each of hydrocarbon and hydroxylated products. These yeast now provide a convenient format for investigating catalytic coupling between terpene synthases and hydroxylases, as well as a platform for the industrial production of high value, single-entity and stereochemically unique terpenes.
143 citations
TL;DR: Proton transfer reaction-mass spectrometry (PTR-MS) was applied to the analysis of a series of volatile organic compounds (VOCs) that emit from various plants.
129 citations
TL;DR: Despite the negligible effect of terpenes on the drug solubility, there was a profound skin penetration enhancement effect, although the terpene enhancers varied in their ability to enhance the flux of diclofenac sodium.
98 citations
TL;DR: Terpene recoveries were decreased with increasing water temperature due to poorer stability of terpenes, and the concentration of carvacrol in the oregano-water extract at 150 degrees C was found to be as high as 4270 microg carVacrol/g oregana.
TL;DR: It is suggested that an ideal terpene enhancer should possess at least one or combinations of the following properties: hydrophobic, in liquid form at room temperature, with an ester or aldehyde but not acid functional group, and is neither a triterpene nor tetraterpene.
TL;DR: The results indicate that the electrophilic oxidation products of linalool which may cause sensitization and irritational skin reactions are not only produced by auto-oxidation reactions in the presence of air-oxygen as published in the past, but also by P450-mediated oxidative biological transformation.
Abstract: The cytochrome P450-mediated oxidative metabolism of the terpene alcohol linalool was studied in vitro by enzymatic assays using recombinant human cytochrome P450 enzymes. Three different enzymatic products of allylic hydroxylation and epoxidation were identified by gas chromatography-mass spectrometry. Identified enzymatic products were 8-hydroxylinalool ((R/S)-3,7-dimethyl-1,6-octadiene-3,8-diol) and the cyclic ethers pyranoid-linalool oxide ((R/S)-2,2,6-trimethyl-6-vinyltetrahydro-2H-pyran-3-ol) and furanoid-linalool oxide (R/S)-2-(1,1-dimethylethyl)-5-methyl-5-vinyltetrahydrofuran. The cyclic ethers result most likely from the epoxidation of the 6,7-carbon double carbon bond of (R/S)-linalool, followed by the intramolecular rearrangement of the 6,7-epoxy-linalool. Allylic-hydroxylation of the 8-methyl group of linalool was catalyzed by CYP2C19 and CYP2D6 while the enzymatic epoxidation of linalool was only observed with CYP2D6. The results indicate that the electrophilic oxidation products of linalool such as 6,7-epoxy-linalool which may cause sensitization and irritational skin reactions are not only produced by auto-oxidation reactions in the presence of air-oxygen as published in the past, but also by P450-mediated oxidative biological transformation.
TL;DR: The preliminary exposure of rumen micro-organisms to a specific blend of essential oils compounds, containing mainly thymol, guajacol and limonene, increased the extent of disappearance of γ-terpinene only, while a third group of one sesquiterpene (α-copaene) and four monoterpenes was extensively degraded by rumenmicro-organisms.
Abstract: The extent of disappearance of 10 mono- and sesquiterpenes in presence of mixed rumen micro-organisms has been measured in 24-h batch cultures. The molecules that were tested are frequently found in the plants consumed by ruminants in highland pastures (limonene, β-myrcene, β-ocimene, α-pinene, sabinene, γ-terpinene and thymol) or are potential markers of the diet (camphene, β-caryophyllene and α-copaene). All terpenes were tested at 2 µL mL−1, except α-copaene and thymol, which were tested at 0.9 µL mL−1 and 2 mg mL−1, respectively. Camphene and thymol were not degraded to a significant extent. The disappearance of part of β-caryophyllene, (−)-limonene and γ-terpinene could not be attributed to the direct action of rumen micro-organisms but rather than to an effect of the extracellular medium. In contrast, a third group of one sesquiterpene (α-copaene) and four monoterpenes (myrcene, β-ocimene, α-pinene and sabinene) was extensively degraded by rumen micro-organisms, at rates of 1.6, 4.5, 3.5, 4.8 and 5.4 µmol mL−1 inoculum day−1, respectively. The preliminary exposure of rumen micro-organisms to a specific blend of essential oils compounds, containing mainly thymol, guajacol and limonene, increased the extent of disappearance of γ-terpinene only. Copyright © 2007 Society of Chemical Industry
TL;DR: A synthetic scheme of the general regulatory network emerging from experimental data is proposed, and the related hypothesis and prospect in elucidating other key events involved in the regulation of TIA terpene moiety biosynthesis are discussed.
Abstract: Precursor feeding experiments have shown that the terpene moiety biosynthesis is the most rate-limiting step of terpenoid indole alkaloids (TIA) produced by Catharanthus roseus suspension cells. The biosynthesis of TIA terpene moiety is strictly regulated by hormones: auxin inhibits, jasmonate stimulates and cytokinin and ethylene enhance their biosynthesis. Biochemical analyses coupled to molecular approaches have outlined a regulatory cross-talk between two metabolite pathways leading to the biosynthesis of terpene precursors. Terpenes derivatives produced through the mevalonic acid (MVA) pathway regulate the activity of the 2-C-methyl-d-erythritol 4-phosphate (MEP) non-mevalonate pathway producing the precursor of the TIA terpene moiety. This cross-talk involves regulatory prenylated proteins and acts on the regulation of the expression of early steps of monoterpenoid biosynthesis (ESMB) genes. The expression of the genes involved in the TIA terpene moiety biosynthesis is regulated in part by a general TIA transcription factor, ORCA3, and other unidentified transcription factors. This review sums up the essential information obtained at the metabolic, physiological, biochemical and molecular levels of regulation of TIA terpene moiety biosynthesis in C. roseus. We propose a synthetic scheme of the general regulatory network emerging from these experimental data, and discuss the related hypothesis and prospect in elucidating other key events involved in the regulation of TIA terpene moiety biosynthesis.
TL;DR: In this article, the authors developed a theoretical equilibrium model of the main synthesis reactions that have been described in the literature plus postulated decomposition reactions, and investigated the decomposition of myrcene experimentally.
TL;DR: Using in vitro and in vivo techniques, terpenes were evaluated as enhancers to improve the skin permeation of therapeutically active agents derived from tea, including tea catechins and theophylline, with alpha-Terpineol found to be the best enhancer.
Abstract: Using in vitro and in vivo techniques, terpenes were evaluated as enhancers to improve the skin permeation of therapeutically active agents derived from tea, including tea catechins and theophylline. The in vitro permeation was determined by Franz cells. The skin deposition and subcutaneous amounts of drugs sampled by microdialysis were evaluated in vivo. Terpenes varied in their activities of enhancing drug permeation. The oxygen-containing terpenes were effective enhancers of drug permeation, whereas the hydrocarbon terpenes were much less efficient. Oxygen-containing terpenes with a bicyclic structure had reduced enhancing activity. Terpenes enhanced tea catechin permeation to a much greater degree than they did theophylline. The isomers of (+)-catechin and (−)-epicatechin showed different permeation behaviors when incorporated with terpenes. In the in vivo status, terpenes promoted the skin uptake but not the subsequent subcutaneous concentration of (−)-epigallocatechin gallate (EGCG). Both increased skin/vehicle partitioning and lipid bilayer disruption of the stratum corneum (SC) contributed the enhancing mechanisms of terpenes for topically applied tea catechins and theophylline based on the experimental results from the partition coefficient and transepidermal water loss (TEWL). α-Terpineol was found to be the best enhancer for catechins and theophylline. The high enhancement by α-terpineol was due to macroscopic perturbation of the SC and the biological reaction in viable skin as evaluated by TEWL and colorimetry.
TL;DR: In the presence of 250 μmol of terpene, the volume of biofilm was reduced by one third in comparison with biofilms in the absence of terpenes, and the extent of cell aggregation decreased from 90% to 10% when carvone concentration reached ca.
TL;DR: The identification and in silico characterization of 49 putative members of the terpene synthase family in diverse Citrus species are identified and the expression patterns and the possible physiological roles of the identified sequences are discussed.
Abstract: Terpenes are a very large and structurally diverse group of secondary metabolites which are abundant in many essential oils, resins and floral scents. Additionally, some terpenes have roles as phytoalexins in plant-pathogen relationships, allelopathic inhibitors in plant-plant interactions, or as airborne molecules of plant-herbivore multitrophic signaling. Thus the elucidation of the biochemistry and molecular genetics of terpenoid biosynthesis has paramount importance in any crop species. With this aim, we searched the CitEST database for clusters of expressed sequence tags (ESTs) coding for terpene synthases. Herein is a report on the identification and in silico characterization of 49 putative members of the terpene synthase family in diverse Citrus species. The expression patterns and the possible physiological roles of the identified sequences are also discussed.
TL;DR: Analysis of monoterpenecomposition of P. abies and A. alba trees showed that the response in terms of the relative proportions of the monoterpene compounds in theresin differed between tree species.
Abstract: Summary ThemonoterpenecompositionofPiceaabiesandAbiesalbaresinwasanalysedinrelationtogrowthbyHeterobasidion spp. Fifteen-year-old P. abies and A. alba trees were inoculated on branches with threespecies of Heterobasidion annosum s.l. After 4 months of incubation, each host was colonized to asignificantlygreaterdegreebythepathogenspecifictothathost(H.parviporumonP.abies,H.abietinumonA.alba)thanbytheotherfungi.Analysisoftheenantiomericmonoterpeneprofilesinthespruceandfir showed that the response in terms of the relative proportions of the monoterpene compounds in theresin differed between tree species. Following challenge with Heterobasidion spp., A. alba trees did notshow changes in monoterpene composition in addition to those in the wounding response (increase in())-a-pineneand())-camphene,and decreasein b-phellandrene). InP.abies,())-a-pinene,(+)-a-pineneand d-3-carene increased following Heterobasidion attack but not after wounding alone. 1 Introduction Plant resin is a mixture of terpenoids, which are complex compounds with varyingchemical properties. Many terpenoids are considered secondary metabolites because theyappear to lack a direct function in basic growth. They are important because they have arole in the chemical defence of plants owing to their antimicrobial, fungistatic andinsecticidal properties, and they are also antifeedant deterrents to insects and mammalianherbivores (Cates 1996; Croteau et al. 2000). Terpenes also have a role in wound healing:Phillips and Croteau (1999) reported that when plant tissue is wounded, the volatileterpene portion of the resin evaporates, leaving a semi-hardened mass resulting from theoxidation and polymerization of diterpenes (Croteau and Johnson 1995).Of the terpenoids, the monoterpenes have the simplest structure (10 carbon atoms) andare an important component of the volatile fraction of oleoresin in plant tissues. Mixturesof terpenes can be constitutive (primary resin) or induced (secondary resin). Constitutiveterpenes are produced by the secretory epithelial cells and accumulate in resin cells. Inaddition to producing primary resin, conifers also possess an inducible terpene defencesystem that is produced by the parenchyma cells when injury occurs. This defence systemleads to the formation of new traumatic resin ducts and increased resin flow in the areasurrounding the injury (Trapp and Croteau 2001; Theis and Lerdau 2003). Theproportion of terpenoids in the primary resin differs from that in secondary resin.Generally the response to aseptic wounds has only minor effects on terpene contentcompared with that caused by infection with a pathogenic fungus (Cheniclet 1987; Raffaand Smalley 1995; Sadof and Grant 1997).The total amount of monoterpenes in tree resin is affected by biotic and abioticstress factors such as drought and fire; however, genetic studies have shown that theFor. Path. 37 (2007) 243–250 2007 The AuthorsJournal compilation 2007 Blackwell Verlag, Berlin
Patent•
13 Feb 2007
TL;DR: In this article, a microorganism capable of producing a terpene of choice is described, which expresses a heterologous pathway for the formation of isoprene units and, preferably, a heter-ologous TERPENE synthase.
Abstract: The present invention relates to a microorganism capable of producing a terpene of choice. The microorganism expresses a heterologous pathway for the formation of isoprene units and, preferably, a heterologous terpene synthase. In this way, high amounts of terpene can be isolated from the medium of the microorganism.
TL;DR: Two eudesmanes, two abietanes, two podocarpanes and other known compounds were isolated from the dried fruits of Juniperus polycarpus var. seravschanica as discussed by the authors.
Abstract: Two eudesmanes, two abietanes, two podocarpanes and other nine known compounds were isolated from the dried fruits of Juniperus polycarpus var. seravschanica. Their structures were established on the basis of analysis of spectroscopic evidence. Some of the isolated terpenoids showed antimalarial activity.
DOI•
07 Nov 2007TL;DR: Using software tools from Genevestigator, a powerful microarray analyzer, multiple tool sets are used to better understand terpene synthase expression in Arabidopsis, which will hopefully open the genetic door to further wet laboratory investigations and can be used to predict roles of terpenes synthase genes in plant cell division and growth.
Abstract: Terpenes are defense chemicals found in wide groups of plants. Terpenoids play a large role in plant development and stress response. The terpene synthase family comprises a diverse set of genes, all which contribute to production of terpenoids. We have used tools of bioinformatics and performed an in silico analysis of developmental and tissue specific terpene synthase gene expression in Arabidopsis thaliana, as well as those expressed due to biotic and abiotic environmental stimuli. Using software tools from Genevestigator, a powerful microarray analyzer, we used multiple tool sets to better understand terpene synthase expression in Arabidopsis, which will hopefully open the genetic door to further wet laboratory investigations. The data can be used to predict roles of terpene synthase genes in plant cell division and growth. The data presented here can be used to model for terpene synthesis expression in other plant species and can also be used to integrate basic plant physiology, and ‘omics’ disciplines.
Journal Article•
TL;DR: The experiments described in this paper propose the evaluation of the plant terpene profile in the culture’s headspace as an early indicator of plant stress through the characterization of plant terPene production.
Abstract: Tissue cultured plants’ vessel headspace is subject to changes during subculture, and the analysis of its variation offers a non-destructive approach for monitoring plant physiology. Among the volatile organic compounds (VOCs) that can be released by plants and be potentially recovered in the airspace of plant tissue cultures, terpenes are very important since they can offer a snapshot of the physiological status of the plant under in vitro cultivation. Terpenes are synthesized from carbon directly shunted from the photosynthetic carbon fixation cycle and their emission is under genetic and environmental control. The experiments described in this paper propose the evaluation of the plant terpene profile in the culture’s headspace as an early indicator of plant stress through the characterization of plant terpene production. Monitoring of terpene emission as a plant response to mechanical stress such as plant wounding showed an increased isoprene and monoterpene emission rates in the first hour after cutting. The comparison of headspace composition of cultures of two fruit rootstocks, Colt and GF677, showed the former having higher emissions of isoprene, α-pinene and limonene than the latter. A decreasing emission trend was observed during subculture, apparently as a result of culture aging. The in vitro headspace analysis of different myrtle (Myrtus communis L.) clones showed a specific and distinctive terpene emission profile. VOC monitoring of in vitro culture headspace is discussed as a non-destructive approach useful for its relation with major physiological activities of culture and for the determination of the potential production of terpenes.
TL;DR: The results show that all the pathways for isopentenyl diphosphate are present in citrus and a high expression of terpene synthases seems to have an important role in the constitution of the essential oils of citrus.
Abstract: Terpenoids constitute the largest and most diverse class of natural products. They are important factors for aroma and flavor, and their synthesis is basically done from two compounds: isopentenyl diphosphate and dimethylallyl diphosphate. Isopentenyl diphosphate is synthesized through two different pathways, one that occurs in the cytoplasm and one in the plastid. With the sequencing of ESTs from citrus, we were able to perform in silico analyses on the pathways that lead to the synthesis of terpenes as well as on the terpene synthases present in sweet orange. Moreover, expression analysis using real-time qPCR was performed to verify the expression pattern of a terpene synthase in plants. The results show that all the pathways for isopentenyl diphosphate are present in citrus and a high expression of terpene synthases seems to have an important role in the constitution of the essential oils of citrus.
Journal Article•
TL;DR: The chemical composition characteristics of Pinus latteri Mason rosin and turpentine from the south of Cambodia was studied using GC and GC-MS in this paper, where nine components were identified from the rosin fraction including 8(14),15-pimaradiene,sandaracopimaric acid,isopimarIC acid,8(9)-isopamide acid,dehydroabietic acid and mercusic acid.
Abstract: The chemical composition characteristics of Pinus latteri Mason rosin and turpentine from the South of Cambodia was studied using GC and GC-MSThe Pinus latteri Mason oleoresin was first separated into two fractions of rosin and turpentine oil,and they were analyzed qualitatively and quantitativelyNine components were identified from the rosin fraction including 8(14),15-pimaradiene,sandaracopimaric acid,isopimaric acid,8(9)-isopimaric acid,dehydroabietic acid,8,12-abietadienoic acid,abietic acid,neoabietic acid and mercusic acidThe proportions of pimarane-type,abietane-type,and dibasic resin acids were 4959 %,3718 % and 124 %,respectivelyThe main resin acids were isopimaric acid,8(9)-isopimaric acid,abietic acid and mercusic acid,and their contents based on rosin weight were 209 %,2114 %,2345 % and 1240 %,respectivelySixteen components in turpentine oil were determined including 13 monoterpenes,2 sesquiterpenes,and one diterpeneMonoterpene was the main component and accounted for 9949 % of turpentine oilThe main monoterpenes were m-mentha-4,8-diene,fenchene and alloocimene,and their contents in turpentine oil were 2401 %,2921 % and 2371 %,respectively
Patent•
19 Nov 2007
TL;DR: In this article, a process for making terpene esters is described, which is based on the reaction of a terpinene alcohol with acetic anhydride in the presence of a high-boiling amine.
Abstract: A process for making terpene esters is disclosed. Reaction of a terpene alcohol with acetic anhydride in the presence of a high-boiling amine provides a terpene ester. Acetic acid, which is distilled from the reaction mixture as it forms, can be recovered. The terpene ester is distilled from the high-boiling amine to provide a product that is substantially free of nitrogen-containing impurities. The reaction mixture can be reused for subsequent acylations. The simple, economical process gives high-quality terpene esters while avoiding waste-disposal issues of other common acylation procedures.
TL;DR: The essential oil of Nothopanax simplex consists largely of myrcene, with smaller amounts of α-pinene, β-pinenes, dipentene, aromadendrene, α- and γ-camphorenes, paraffin wax and other unidentified terpenes and sesquiterpenes as discussed by the authors.
Abstract: The essential oil of Nothopanax simplex consists largely of myrcene, with smaller amounts of α-pinene, β-pinene, dipentene, aromadendrene, α- and γ-camphorenes, paraffin wax and other unidentified terpenes and sesquiterpenes.