SEARCH · Search PubMed

Results for “TERPENES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources

PubMed2000

Rapid analysis of terpene lactones in extract of Ginkgo biloba L. by high performance liquid chromatography.

A new rapid analytical method was developed for the quantification of terpene lactones (bilobalide(BB) and ginkgolide A, B, C, J) in extract of Ginkgo biloba L. (EGb) using a liquid-liquid solvent extraction procedure followed by high performance liquid chromatography. EGb was dissolved in 30% ethanol and extracted with ether. After evaporation, the residue was then determined by HPLC on a C18 column with methanol-water-orthophosphoric acid (25:75:0.1, V/V) as eluent and refractive index (RI) detection. Results showed that the excellent sample clean-up procedure is more simple and specific, and saves more time (less than 20 min) than any other methods that have been reported, and also leads to high recoveries (> 99.0%) and low RSDs (< 2.0%). The reproducible method is regarded to be very useful for evaluating the quality of extract of Ginkgo biloba L.

Chromatography, High Pressure Liquid↗

PubMed2004

Synthesis of 4-aryl substituted semicarbazones of some terpenes as novel anticonvulsants.

PURPOSE: A series of 4-aryl substituted semicarbazones of citral and R- (-) carvone were designed and synthesized to meet the structural requirements essential for anticonvulsant activity. METHODS: TLC evaluated purity of synthesized compounds and their structure confirmed by infrared spectroscopy, proton magnetic resonance spectroscopy and by nitrogen estimation. All the compounds were evaluated for anticonvulsant activity by maximal electroshock (MES) and subcutaneous metrazol (ScMet) induced seizure methods and minimal motor impairment was determined by rotorod test. RESULTS: All the synthesized compounds exhibited significant protection after intraperitoneal (i.p.) administration in MES. Seventy two percent of the compounds exhibited protection in ScMet test. Some of them also showed good activity after oral administration. The results showed that anticonvulsants with cyclic and acyclic terpenoid moiety retain activity in MES as well as ScMet test. The p-fluoro aryl substituted semicarbazones emerged as the most active analogue in both cyclic and acyclic terpenes. CONCLUSION: Semicarbazones with terpenoid as the lipophilic moiety resulted in compounds with broad spectrum of anticonvulsant activity and therefore, they may be utilized for the future development of novel anticonvulsants with broad spectrum of anticonvulsant activity. The results also validated pharmacophore model with four binding sites essential for anticonvulsant activity.

Acyclic Monoterpenes↗

PubMed2006

[Study on terpene of Dryopteris fragrans L].

OBJECTIVE: To study the terpene of Dryopteris fragrans. METHODS: Isolation and purification were carried out on repeated silica gel, Sephadex LH-20 column chromatography and prepare HPLC. The structures of the compounds were determined by physicochemical properties and spectral analysis. RESULTS: Four compounds were isolated and identified as 10-hydroxyl-15-oxo-alpha-cadinol (I), albicany acetate (II), alpha-cadinene (III), albicanol (IV). CONCLUSION: Compounds I is isolated from this plant for the first time.

Dryopteris↗

PubMed2005

Enantiomeric differentiation of acyclic terpenes by 13C NMR spectroscopy using a chiral lanthanide shift reagent.

The 13C NMR behaviour of ten acyclic terpene alcohols was examined in the presence of a chiral lanthanide shift reagent (CLSR). For each alcohol, we measured the lanthanide-induced shift (LIS) on the signals of the carbons and the splitting of some signals, which allowed the enantiomeric differentiation. As expected, the LIS decreased with the number of bonds between the binding function and the considered carbon. The enantiomeric splitting is observed for several signals in the spectrum of each compound. The influence of the hindrance of the binding function (primary, secondary or tertiary alcohol) and that of the stereochemistry of the double bonds is discussed.

Journal Article↗

PubMed2006

Cytotoxic terpenes and lignans from the roots of Ainsliaea acerifolia.

The chromatographic separation of the MeOH extract of the roots of Ainsliaea acerifolia (Compositae) led to the isolation of six known terpenes and two known lignans. Their structures were identified by spectroscopic methods as mokko lactone (1), betulonic acid (2), betulinic acid (3), zaluzanin C (4), 1beta-hydroperoxygermacra-4(15),5,10(14)-triene (5), pluviatilol (6), (+)-syringaresinol (7), and glucozaluzanin C (8). Compounds 1 approximately 4 and 8 showed non-specific significant cytotoxicity against five human tumor cell lines with ED50 values ranging from 0.36 approximately 5.54 microg/mL.

Antineoplastic Agents, Phytogenic↗

PubMed1992

Evidence for an essential histidine residue in 4S-limonene synthase and other terpene cyclases.

(4S)-Limonene synthase, isolated from glandular trichome secretory cell preparations of Mentha x piperita (peppermint) leaves, catalyzes the metal ion-dependent cyclization of geranyl pyrophosphate, via 3S-linalyl pyrophosphate, to (-)-(4S)-limonene as the principal product. Treatment of this terpene cyclase with the histidine-directed reagent diethyl pyrocarbonate at a concentration of 0.25 mM resulted in 50% loss of enzyme activity, and this activity could be completely restored by treatment of the preparation with 5 mM hydroxylamine. Inhibition with diethyl pyrocarbonate was distinguished from inhibition with thiol-directed reagents by protection studies with histidine and cysteine carried out at varying pH. Inactivation of the cyclase by dye-sensitized photooxidation in the presence of rose bengal gave further indication of the presence of a readily modified histidine residue. Protection of the enzyme against inhibition with diethyl pyrocarbonate was afforded by the substrate geranyl pyrophosphate in the presence of Mn2+, and by the sulfonium ion analog of the linalyl carbocation intermediate of the reaction in the presence of inorganic pyrophosphate plus Mn2+, suggesting that an essential histidine residue is located at or near the active site. Similar studies on the inhibition of other monoterpene and sesquiterpene cyclases with diethyl pyrocarbonate suggest that a histidine residue (or residues) may play an important role in catalysis by this class of enzymes.

Binding Sites↗

PubMedDate not supplied

Fluorescence enhancement of two terpenes commonly present in essential oils.

The fluorescence spectra of anethole and eugenol dissolved in methanol-aqueous binary systems with the addition of alpha- and beta-cyclodextrin were studied. Observed enhancement of the fluorescence intensity is possibly due to the higher quantum yield of the cyclodextrin-hydrocarbon inclusion complexes. The measured fluorescence intensities for eugenol and anethole in the presence of alpha- and beta-cyclodextrin were processed using principal component analysis. The results obtained suggest 1:1 and 2:1 complexation, as confirmed by a double reciprocal plot for terpenes complexed to cyclodextrins. In both cases (anethole and eugenol) detection limits were improved after addition of cyclodextrins. This phenomenon can be applied for improvement of direct fluorescence and HPLC-fluorescence assays.

Allylbenzene Derivatives↗

PubMed2004

Identification of Vitis vinifera (-)-alpha-terpineol synthase by in silico screening of full-length cDNA ESTs and functional characterization of recombinant terpene synthase.

The flavour and aroma of certain Vitis vinifera grape varieties is dominated by volatile terpenes and small volatile aldehydes. Monoterpenes contribute to the final grape and wine aroma and flavour in form of free volatiles and as glycoside conjugates of monoterpene alcohols. Typical monoterpenol components of the cultivar Gewürztraminer and other aroma-rich grape varieties are linalool, geraniol, nerol, citronellol, and alpha-terpineol. In a functional genomics effort to identify genes for the formation of monoterpene alcohols in V. vinifera, a database of full-length cDNA sequences was screened in silico and yielded two clones for putative monoterpene synthases. The gene products were functionally characterized by expression in Escherichia coli, in vitro enzyme assay and gas chromatography-mass spectrometry (GC-MS) product identification as multi-product (-)-alpha-terpineol synthases.

Alkyl and Aryl Transferases↗

PubMed2003

Probing sesquiterpene hydroxylase activities in a coupled assay with terpene synthases.

5-epi-Aristolochene dihydroxylase (EAH) catalyzes unique stereo- and regiospecific hydroxylations of a bicyclic sesquiterpene hydrocarbon to generate capsidiol. To define functional and mechanistic features of the EAH enzyme, the utility of a coupled assay using readily available sesquiterpene synthases and microsomes from yeast overexpressing the EAH enzyme was determined. Capsidiol and deoxycapsidiol biosyntheses were readily measured in coupled assays consisting of 5-epi-aristolochene synthase and EAH as determined by the incorporation of radiolabeled farnesyl diphosphate into thin-layer chromatography-isolated products and verified by gas chromatography-mass spectrometry analysis. The assays were dependent on the amounts of synthase and hydroxylase protein added, the incubation times, and the presence of nicotinamide adenine dinucleotide phosphate. The utility of this coupled assay was extended by examining the relative efficiency of the EAH enzyme to catalyze hydroxylations of different sesquiterpene skeletons generated by other terpene synthases.

Alkyl and Aryl Transferases↗

PubMed2002

The propolis of stingless bees: terpenes from the tibia of three Frieseomelitta species.

The posterior tibia of foraging workers of three species of Frieseomelitta (Hymenoptera: Meliponinae) stingless bees have been shown to carry complex mixtures of plant-derived mono-, sesqui-, di- and tri-terpenes. These subtances were not found on the fore- or mid-legs, nor on other parts of the hind legs. F. silvestrii and F. silvestrii languida, when collecting, appear to exploit different plants for their resin even when housed in the same area. F. varia were found to be not collecting resin at the time of the initial sampling and were therefore sampled later. Mature foragers carry the resin. In the samples studied here, particularly prominent were the monoterpene alpha-pinene, the sesquiterpenes beta-caryophyllene, alpha-cubebene, alpha- and gamma-muurolene, gamma-cadinene, germacrene-D, and elemol and the diterpenes manool and totarol The collected material is used for the resin placed around the entrance to their nests and is also mixed with wax, to produce the cerum used for the structures in the nest.

Journal Article↗

PubMed2001

Molecular-imprinted, polymer-coated quartz crystal microbalances for the detection of terpenes.

A piezoelectric sensor coated with an artificial biomimetic recognition element has been developed for the determination of L-menthol in the liquid phase. A highly specific noncovalently imprinted polymer (MIP) was cast in situ on to the surface of a gold-coated quartz crystal microbalance (QCM) electrode as a thin permeable film. Selective rebinding of the target analyte was observed as a frequency shift quantified by piezoelectric microgravimetry with the QCM. The detectability of L-menthol was 200 ppb with a response range of 0-1.0 ppm. The response of the MIP-QCM to a range of monoterpenes was investigated with the sensor binding menthol in favor of analogous compounds. The sensor was able to distinguish between the D- and L-enantiomers of menthol owing to the enantioselectivity of the imprinted sites. To our knowledge, this is the first report describing enantiomeric resolution within an MIP utilizing a single monomer-functional moiety interaction. It is envisaged that this technique could be employed to determine the concentration of terpenes in the atmosphere.

Journal Article↗

PubMed2002

X-ray crystal structures of D100E trichodiene synthase and its pyrophosphate complex reveal the basis for terpene product diversity.

The 2.4 A resolution X-ray crystal structure of D100E trichodiene synthase and the 2.6 A resolution structure of its complex with inorganic pyrophosphate are reported. The D100E amino acid substitution in the so-called "aspartate-rich" motif does not result in large changes to the overall structure of the enzyme. In the pyrophosphate complex, however, pyrophosphate coordinates two Mg(2+) ions at the mouth of the active site without causing large changes in the structure of the enzyme. This contrasts with pyrophosphate binding in the wild-type enzyme, where pyrophosphate coordinates three Mg(2+) ions and triggers a significant conformational change that closes the mouth of the active site and optimizes packing density in the enzyme-substrate complex. The attenuation of active site closure in D100E trichodiene synthase compromises enzyme-substrate packing density and confers additional spatial and conformational degrees of freedom on the substrate and carbocation intermediates, which in turn results in the formation of five alternate sesquiterpene products in addition to trichodiene. By extension, then, the diversity of terpene cyclases in biology may have evolved in part by amino acid substitutions that fine-tune structural changes dependent on metal-diphosphate complexation that govern the formation of the active site template and enzyme-substrate packing density.

Amino Acid Substitution↗

PubMed2003

Acid-catalyzed Grob fragmentation reactions of acetonides derived from terpenes.

[reaction: see text] Acetonides derived from different terpenes undergo Grob fragmentation by treatment with a catalytic amount of acid, triflic acid, or boron trifluoride, giving aldehydes containing a cyclopropane or cyclobutane ring with good yields and complete diastereoselectivity. The structure and the stereochemistry of the starting acetonide have a crucial influence on the reaction course.

Journal Article↗

PubMed2004

Antiviral and antiplasmodial spirodihydrobenzofuran terpenes from the fungus Stachybotrys nephrospora.

Two known spirodihydrobenzofuran terpenes (1 and 2) were isolated from a mycelium extract of the fungus Stachybotrys nephrospora BCC 3900. Compound 1 (Mer-NF5003F or stachybotrydial) exhibited potent antiviral activity (the IC50 value of 4.32 microg/mL) comparable to the standard drug, acyclovir, while compound 2 was inactive against the HSV-1 virus. Both 1 and 2 possessed antiplasmodial activity (IC50 values of 0.85 and 0.15 microg/mL for 1 and 2, respectively), and were not toxic towards the Vero cell line. A regiospecific conversion of the dialdehyde 1 to the lactone 2 proceeded simply under acidic conditions.

Animals↗

PubMed2004

Dermal exposure to terpenic resin acids in Swedish carpentry workshops and sawmills.

OBJECTIVES: The aim of this study was to evaluate dermal exposure to the resin acids abietic acid, dehydroabietic acid and 7-oxodehydroabietic acid during collecting in sawmills and during sawing in carpentry workshops, respectively. METHODS: Sampling was performed by fastening patches at 12 different areas on a sampling overall, one patch on the front of a cap, one patch on the chest inside the clothing and one patch on the inner lower right leg. Exposure of the hands was assessed by fastening patches on cotton gloves representing the dorsal sides and the palms of the left and right hands. Sampling was performed on 30 different occasions in the sawmills and in the carpentry workshops with mean sampling times of 120 and 59 min, respectively. The acids were solvent desorbed from the patches. Identification and quantification of the resin acids was performed by gas chromatography-mass spectrometry. RESULTS: The geometric means (GMs) of the potential body exposures to abietic acid, dehydroabietic acid and 7-oxodehydroabietic acid during sawing and collecting of wood from pine and spruce were 3346 and 17 247 micro g/h, respectively. The GM of the potential exposure on the hands was 3020 micro g/h in the carpentry workshops and 4365 micro g/h in the sawmills. Resin acids were detected on the inner chest and inner lower front right leg, respectively. CONCLUSIONS: There is a potential dermal exposure to terpenic resin acids in carpentry workshops as well as in sawmills. The hands have the highest exposure during sawing as well as during collecting. There is a spatial distribution of contaminants, with the outer chest, arms and legs showing the highest exposures. Resin acids also contaminated the inner chest and inner lower leg. It is necessary to take action to reduce dermal exposure to these allergenic substances.

Abietanes↗

PubMed2004

Functional characterization of nine Norway Spruce TPS genes and evolution of gymnosperm terpene synthases of the TPS-d subfamily.

Constitutive and induced terpenoids are important defense compounds for many plants against potential herbivores and pathogens. In Norway spruce (Picea abies L. Karst), treatment with methyl jasmonate induces complex chemical and biochemical terpenoid defense responses associated with traumatic resin duct development in stems and volatile terpenoid emissions in needles. The cloning of (+)-3-carene synthase was the first step in characterizing this system at the molecular genetic level. Here we report the isolation and functional characterization of nine additional terpene synthase (TPS) cDNAs from Norway spruce. These cDNAs encode four monoterpene synthases, myrcene synthase, (-)-limonene synthase, (-)-alpha/beta-pinene synthase, and (-)-linalool synthase; three sesquiterpene synthases, longifolene synthase, E,E-alpha-farnesene synthase, and E-alpha-bisabolene synthase; and two diterpene synthases, isopimara-7,15-diene synthase and levopimaradiene/abietadiene synthase, each with a unique product profile. To our knowledge, genes encoding isopimara-7,15-diene synthase and longifolene synthase have not been previously described, and this linalool synthase is the first described from a gymnosperm. These functionally diverse TPS account for much of the structural diversity of constitutive and methyl jasmonate-induced terpenoids in foliage, xylem, bark, and volatile emissions from needles of Norway spruce. Phylogenetic analyses based on the inclusion of these TPS into the TPS-d subfamily revealed that functional specialization of conifer TPS occurred before speciation of Pinaceae. Furthermore, based on TPS enclaves created by distinct branching patterns, the TPS-d subfamily is divided into three groups according to sequence similarities and functional assessment. Similarities of TPS evolution in angiosperms and modeling of TPS protein structures are discussed.

Alkyl and Aryl Transferases↗

PubMed2006

Wound-induced terpene synthase gene expression in Sitka spruce that exhibit resistance or susceptibility to attack by the white pine weevil.

We analyzed the expression pattern of various terpene synthase (TPS) genes in response to a wounding injury applied to the apical leader of Sitka spruce (Picea sitchensis Bong. Carr.) genotypes known to be resistant (R) or susceptible (S) to white pine weevil (Pissodes strobi Peck.) attack. The purpose was to test if differences in constitutive or wound-induced TPS expression can be associated with established weevil resistance. All wounding treatments were conducted on 9-year-old R and S trees growing under natural field conditions within the range of variation for weevil R and S genotypes. Representative cDNAs of the monoterpene synthase (mono-TPS), sesquiterpene synthase (sesqui-TPS), and diterpene synthase (di-TPS) classes were isolated from Sitka spruce to assess TPS transcript levels. Based on amino acid sequence similarity, the cDNAs resemble Norway spruce (Picea abies) (-)-linalool synthase (mono-TPS; PsTPS-Linl) and levopimaradiene/abietadiene synthase (di-TPS; PsTPS-LASl), and grand fir (Abies grandis) delta-selinene synthase (sesqui-TPS; PsTPS-Sell). One other mono-TPS was functionally identified as (-)-limonene synthase (PsTPS-Lim). No significant difference in constitutive expression levels for these TPSs was detected between R and S trees. However, over a postwounding period of 16 d, only R trees exhibited significant transcript accumulation for the mono- and sesqui-TPS tested. Both R and S trees exhibited a significant accumulation of PsTPS-LASl transcripts. An assessment of traumatic resin duct formation in wounded leaders showed that both R and S trees responded by forming traumatic resin ducts; however, the magnitude of this response was significantly greater in R trees. Collectively, our data imply that the induced resinosis response is an important aspect of defense in weevil R Sitka spruce trees growing under natural conditions.

Alkyl and Aryl Transferases↗

PubMed2025

Comparative genomic analysis of Artemisia argyi reveals asymmetric expansion of terpene synthases and conservation of artemisinin biosynthesis.

Artemisia argyi, a perennial herb of the Asteraceae family, possesses significant therapeutic and economic value. We present a 7.88 Gb chromosome-level haplotype-resolved genome assembly, revealing its unique evolutionary trajectory. The karyotype (2n = 34) of A. argyi is that of an autotetraploid, which underwent gametic chromosome fusion prior to species-specific whole-genome duplication (WGD-3). The genome exhibits pronounced multivalent chromosome pairing and frequent recombination among homologous groups. Asymmetrical evolution following WGD-3 is a hallmark feature, evidenced by imbalanced allelic gene loss and widespread neofunctionalization. The terpene synthase (TPS) gene family exemplifies this pattern, having expanded through four duplication events in A. argyi. Recent tandem duplications and allelic functional differentiation have generated substantial gene functional diversity. Notably, we identified a tandem-duplicated six-copy ADS homolog (AarADS)-a key TPS gene in the artemisinin biosynthetic pathway of Artemisia annua (AanADS)-localized exclusively to a single chromosome in A. argyi. Unlike AanADS, which converts farnesyl pyrophosphate (FPP) to amorpha-4,11-diene, AarADS catalyzes FPP to α-bisabolol. Evolutionary analysis suggested that AanADS acquired its specialized function via a derived mutation in the A. annua lineage. This study elucidates the genomic evolution underpinning A. argyi's distinctive medicinal properties.

Alkyl and Aryl Transferases↗