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Dae-kyun Ro - One of the best experts on this subject based on the ideXlab platform.
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molecular cloning and characterization of drimenol synthase from valerian plant Valeriana officinalis
FEBS Letters, 2014Co-Authors: Moonhyuk Kwon, Stephen A. Cochrane, John C. Vederas, Dae-kyun RoAbstract:Drimenol, a sesquiterpene alcohol, and its derivatives display diverse bio-activities in nature. However, a drimenol synthase gene has yet to be identified. We identified a new sesquiterpene synthase cDNA (VoTPS3) in valerian plant (Valeriana officinalis). Purification and NMR analyses of the VoTPS3-produced terpene, and characterization of the VoTPS3 enzyme confirmed that VoTPS3 synthesizes (−)-drimenol. In feeding assays, possible reaction intermediates, farnesol and drimenyl diphosphate, could not be converted to drimenol, suggesting that the intermediate remains tightly bound to VoTPS3 during catalysis. A mechanistic consideration of (−)-drimenol synthesis suggests that drimenol synthase is likely to use a protonation-initiated cyclization, which is rare for sesquiterpene synthases. VoTPS3 can be used to produce (−)-drimenol, from which useful drimane-type terpenes can be synthesized.
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enzymatic synthesis of valerena 4 7 11 diene by a unique sesquiterpene synthase from the valerian plant Valeriana officinalis
FEBS Journal, 2012Co-Authors: Bryan W Pyle, John C. Vederas, Hue T Tran, Benjamin Pickel, Tegan M Haslam, Gillian Macnevin, Dae-kyun RoAbstract:Valerian (Valeriana officinalis) is a popular medicinal plant in North America and Europe. Its root extract is commonly used as a mild sedative and anxiolytic. Among dozens of chemical constituents (e.g. alkaloids, iridoids, flavonoids, and terpenoids) found in valerian root, valerena-4,7(11)-diene and valerenic acid (C15 sesquiterpenoid) have been suggested as the active ingredients responsible for the sedative effect. However, the biosynthesis of the valerena-4,7(11)-diene hydrocarbon skeleton in valerian remains unknown to date. To identify the responsible terpene synthase, next-generation sequencing (Roche 454 pyrosequencing) was used to generate ∼ 1 million transcript reads from valerian root. From the assembled transcripts, two sesquiterpene synthases were identified (VoTPS1 and VoTPS2), both of which showed predominant expression patterns in root. Transgenic yeast expressing VoTPS1 and VoTPS2 produced germacrene C/germacrene D and valerena-4,7(11)-diene, respectively, as major terpene products. Purified VoTPS1 and VoTPS2 recombinant enzymes confirmed these activities in vitro, with competent kinetic properties (Km of ∼ 10 μm and kcat of 0.01 s−1 for both enzymes). The structure of the valerena-4,7(11)-diene produced from the yeast expressing VoTPS2 was further substantiated by 13C-NMR and GC-MS in comparison with the synthetic standard. This study demonstrates an integrative approach involving next-generation sequencing and metabolically engineered microbes to expand our knowledge of terpenoid diversity in medicinal plants. Database The sequences of cDNAs described in this work are available in the GenBank database under the following accession numbers: VoTPS1, JQ437839; VoTPS2, JQ437840
Ilkwon Park - One of the best experts on this subject based on the ideXlab platform.
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nematicidal activity of plant essential oils and components from coriander coriandrum sativum oriental sweetgum liquidambar orientalis and valerian Valeriana wallichii essential oils against pine wood nematode bursaphelenchus xylophilus
Journal of Agricultural and Food Chemistry, 2008Co-Authors: Sangchul Shin, Ilkwon ParkAbstract:Commercial essential oils from 28 plant species were tested for their nematicidal activities against the pine wood nematode, Bursaphelenchus xylophilus. Good nematicidal activity against B. xylophilus was achieved with essential oils of coriander (Coriandrum sativum), Oriental sweetgum (Liquidambar orientalis), and valerian (Valeriana wallichii). Analysis by gas chromatography−mass spectrometry led to the identification of 26, 11, and 4 major compounds from coriander (Coriandrum sativum), Oriental sweetgum (Liquidambar orientalis), and valerian (Valeriana wallichii) oils, respectively. Compounds from each plant essential oil were tested individually for their nematicidal activities against the pine wood nematode. Among the compounds, benzaldehyde, trans-cinnamyl alcohol, cis-asarone, octanal, nonanal, decanal, trans-2-decenal, undecanal, dodecanal, decanol, and trans-2-decen-1-ol showed strong nematicidal activity. The essential oils described herein merit further study as potential nematicides against th...
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nematicidal activity of plant essential oils and components from coriander coriandrum sativum oriental sweetgum liquidambar orientalis and valerian Valeriana wallichii essential oils against pine wood nematode bursaphelenchus xylophilus
Journal of Agricultural and Food Chemistry, 2008Co-Authors: Junheon Kim, Sangchul Shin, Sunmi Seo, Sang Gil Lee, Ilkwon ParkAbstract:Commercial essential oils from 28 plant species were tested for their nematicidal activities against the pine wood nematode, Bursaphelenchus xylophilus. Good nematicidal activity against B. xylophilus was achieved with essential oils of coriander (Coriandrum sativum), Oriental sweetgum (Liquidambar orientalis), and valerian (Valeriana wallichii). Analysis by gas chromatography-mass spectrometry led to the identification of 26, 11, and 4 major compounds from coriander (Coriandrum sativum), Oriental sweetgum (Liquidambar orientalis), and valerian (Valeriana wallichii) oils, respectively. Compounds from each plant essential oil were tested individually for their nematicidal activities against the pine wood nematode. Among the compounds, benzaldehyde, trans-cinnamyl alcohol, cis-asarone, octanal, nonanal, decanal, trans-2-decenal, undecanal, dodecanal, decanol, and trans-2-decen-1-ol showed strong nematicidal activity. The essential oils described herein merit further study as potential nematicides against the pine wood nematode.
John C. Vederas - One of the best experts on this subject based on the ideXlab platform.
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molecular cloning and characterization of drimenol synthase from valerian plant Valeriana officinalis
FEBS Letters, 2014Co-Authors: Moonhyuk Kwon, Stephen A. Cochrane, John C. Vederas, Dae-kyun RoAbstract:Drimenol, a sesquiterpene alcohol, and its derivatives display diverse bio-activities in nature. However, a drimenol synthase gene has yet to be identified. We identified a new sesquiterpene synthase cDNA (VoTPS3) in valerian plant (Valeriana officinalis). Purification and NMR analyses of the VoTPS3-produced terpene, and characterization of the VoTPS3 enzyme confirmed that VoTPS3 synthesizes (−)-drimenol. In feeding assays, possible reaction intermediates, farnesol and drimenyl diphosphate, could not be converted to drimenol, suggesting that the intermediate remains tightly bound to VoTPS3 during catalysis. A mechanistic consideration of (−)-drimenol synthesis suggests that drimenol synthase is likely to use a protonation-initiated cyclization, which is rare for sesquiterpene synthases. VoTPS3 can be used to produce (−)-drimenol, from which useful drimane-type terpenes can be synthesized.
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enzymatic synthesis of valerena 4 7 11 diene by a unique sesquiterpene synthase from the valerian plant Valeriana officinalis
FEBS Journal, 2012Co-Authors: Bryan W Pyle, John C. Vederas, Hue T Tran, Benjamin Pickel, Tegan M Haslam, Zhizeng Gao, Gillian Macnevin, Sooun KimAbstract:Valerian (Valeriana officinalis) is a popular medicinal plant in North America and Europe. Its root extract is commonly used as a mild sedative and anxiolytic. Among dozens of chemical constituents (e.g. alkaloids, iridoids, flavonoids, and terpenoids) found in valerian root, valerena-4,7(11)-diene and valerenic acid (C15 sesquiterpenoid) have been suggested as the active ingredients responsible for the sedative effect. However, the biosynthesis of the valerena-4,7(11)-diene hydrocarbon skeleton in valerian remains unknown to date. To identify the responsible terpene synthase, next-generation sequencing (Roche 454 pyrosequencing) was used to generate ∼ 1 million transcript reads from valerian root. From the assembled transcripts, two sesquiterpene synthases were identified (VoTPS1 and VoTPS2), both of which showed predominant expression patterns in root. Transgenic yeast expressing VoTPS1 and VoTPS2 produced germacrene C/germacrene D and valerena-4,7(11)-diene, respectively, as major terpene products. Purified VoTPS1 and VoTPS2 recombinant enzymes confirmed these activities in vitro, with competent kinetic properties (K(m) of ∼ 10 μm and k(cat) of 0.01 s(-1) for both enzymes). The structure of the valerena-4,7(11)-diene produced from the yeast expressing VoTPS2 was further substantiated by (13) C-NMR and GC-MS in comparison with the synthetic standard. This study demonstrates an integrative approach involving next-generation sequencing and metabolically engineered microbes to expand our knowledge of terpenoid diversity in medicinal plants.
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enzymatic synthesis of valerena 4 7 11 diene by a unique sesquiterpene synthase from the valerian plant Valeriana officinalis
FEBS Journal, 2012Co-Authors: Bryan W Pyle, John C. Vederas, Hue T Tran, Benjamin Pickel, Tegan M Haslam, Gillian Macnevin, Dae-kyun RoAbstract:Valerian (Valeriana officinalis) is a popular medicinal plant in North America and Europe. Its root extract is commonly used as a mild sedative and anxiolytic. Among dozens of chemical constituents (e.g. alkaloids, iridoids, flavonoids, and terpenoids) found in valerian root, valerena-4,7(11)-diene and valerenic acid (C15 sesquiterpenoid) have been suggested as the active ingredients responsible for the sedative effect. However, the biosynthesis of the valerena-4,7(11)-diene hydrocarbon skeleton in valerian remains unknown to date. To identify the responsible terpene synthase, next-generation sequencing (Roche 454 pyrosequencing) was used to generate ∼ 1 million transcript reads from valerian root. From the assembled transcripts, two sesquiterpene synthases were identified (VoTPS1 and VoTPS2), both of which showed predominant expression patterns in root. Transgenic yeast expressing VoTPS1 and VoTPS2 produced germacrene C/germacrene D and valerena-4,7(11)-diene, respectively, as major terpene products. Purified VoTPS1 and VoTPS2 recombinant enzymes confirmed these activities in vitro, with competent kinetic properties (Km of ∼ 10 μm and kcat of 0.01 s−1 for both enzymes). The structure of the valerena-4,7(11)-diene produced from the yeast expressing VoTPS2 was further substantiated by 13C-NMR and GC-MS in comparison with the synthetic standard. This study demonstrates an integrative approach involving next-generation sequencing and metabolically engineered microbes to expand our knowledge of terpenoid diversity in medicinal plants. Database The sequences of cDNAs described in this work are available in the GenBank database under the following accession numbers: VoTPS1, JQ437839; VoTPS2, JQ437840
Bryan W Pyle - One of the best experts on this subject based on the ideXlab platform.
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enzymatic synthesis of valerena 4 7 11 diene by a unique sesquiterpene synthase from the valerian plant Valeriana officinalis
FEBS Journal, 2012Co-Authors: Bryan W Pyle, John C. Vederas, Hue T Tran, Benjamin Pickel, Tegan M Haslam, Zhizeng Gao, Gillian Macnevin, Sooun KimAbstract:Valerian (Valeriana officinalis) is a popular medicinal plant in North America and Europe. Its root extract is commonly used as a mild sedative and anxiolytic. Among dozens of chemical constituents (e.g. alkaloids, iridoids, flavonoids, and terpenoids) found in valerian root, valerena-4,7(11)-diene and valerenic acid (C15 sesquiterpenoid) have been suggested as the active ingredients responsible for the sedative effect. However, the biosynthesis of the valerena-4,7(11)-diene hydrocarbon skeleton in valerian remains unknown to date. To identify the responsible terpene synthase, next-generation sequencing (Roche 454 pyrosequencing) was used to generate ∼ 1 million transcript reads from valerian root. From the assembled transcripts, two sesquiterpene synthases were identified (VoTPS1 and VoTPS2), both of which showed predominant expression patterns in root. Transgenic yeast expressing VoTPS1 and VoTPS2 produced germacrene C/germacrene D and valerena-4,7(11)-diene, respectively, as major terpene products. Purified VoTPS1 and VoTPS2 recombinant enzymes confirmed these activities in vitro, with competent kinetic properties (K(m) of ∼ 10 μm and k(cat) of 0.01 s(-1) for both enzymes). The structure of the valerena-4,7(11)-diene produced from the yeast expressing VoTPS2 was further substantiated by (13) C-NMR and GC-MS in comparison with the synthetic standard. This study demonstrates an integrative approach involving next-generation sequencing and metabolically engineered microbes to expand our knowledge of terpenoid diversity in medicinal plants.
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enzymatic synthesis of valerena 4 7 11 diene by a unique sesquiterpene synthase from the valerian plant Valeriana officinalis
FEBS Journal, 2012Co-Authors: Bryan W Pyle, John C. Vederas, Hue T Tran, Benjamin Pickel, Tegan M Haslam, Gillian Macnevin, Dae-kyun RoAbstract:Valerian (Valeriana officinalis) is a popular medicinal plant in North America and Europe. Its root extract is commonly used as a mild sedative and anxiolytic. Among dozens of chemical constituents (e.g. alkaloids, iridoids, flavonoids, and terpenoids) found in valerian root, valerena-4,7(11)-diene and valerenic acid (C15 sesquiterpenoid) have been suggested as the active ingredients responsible for the sedative effect. However, the biosynthesis of the valerena-4,7(11)-diene hydrocarbon skeleton in valerian remains unknown to date. To identify the responsible terpene synthase, next-generation sequencing (Roche 454 pyrosequencing) was used to generate ∼ 1 million transcript reads from valerian root. From the assembled transcripts, two sesquiterpene synthases were identified (VoTPS1 and VoTPS2), both of which showed predominant expression patterns in root. Transgenic yeast expressing VoTPS1 and VoTPS2 produced germacrene C/germacrene D and valerena-4,7(11)-diene, respectively, as major terpene products. Purified VoTPS1 and VoTPS2 recombinant enzymes confirmed these activities in vitro, with competent kinetic properties (Km of ∼ 10 μm and kcat of 0.01 s−1 for both enzymes). The structure of the valerena-4,7(11)-diene produced from the yeast expressing VoTPS2 was further substantiated by 13C-NMR and GC-MS in comparison with the synthetic standard. This study demonstrates an integrative approach involving next-generation sequencing and metabolically engineered microbes to expand our knowledge of terpenoid diversity in medicinal plants. Database The sequences of cDNAs described in this work are available in the GenBank database under the following accession numbers: VoTPS1, JQ437839; VoTPS2, JQ437840
Andrés Navarrete - One of the best experts on this subject based on the ideXlab platform.
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Chemical fingerprinting of Valeriana species: simultaneous determination of valerenic acids, flavonoids, and phenylpropanoids using liquid chromatography with ultraviolet detection.
Journal of AOAC International, 2006Co-Authors: Andrés Navarrete, Bharathi Avula, Young-whan Choi, Ikhlas A. KhanAbstract:The roots and rhizomes of various Valeriana species are currently used as a sleeping aid or mild sedative. A liquid chromatography method has been developed that permits the analysis of chlorogenic acid, lignans, flavonoids, valerenic acids, and valpotrates in various valerian samples. The best results were obtained with a Phenomenex Luna C18(2) column using gradient elution with a mobile phase consisting of water and 0.05% phosphoric acid and 2-100% acetonitrile-methanol (1 + 1) with 0.05% phosphoric acid. The flow rate was 0.8 mL/min and ultraviolet detection was at 207, 225, 254, 280, and 325 nm. Different valerian species and commercial products showed remarkable quantitative variations. Chlorogenic acid (0.2-1.2%), 3 lignans, linarin (0.002-0.24%), and valepotriates were detected in all the Valeriana species analyzed. Highest amounts of valerenic acids were detected in V. officinalis L., trace amounts in V. sitchensis, and none in the other species analyzed.
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Authentication of Valeriana procera Kunth and comparative account of five Valeriana species.
Journal of AOAC International, 2005Co-Authors: Vaishali C. Joshi, Andrés Navarrete, Ikhlas A. KhanAbstract:Valeriana procera Kunth (Mexican Valerian) is a commercially important species, sometimes used as a substitute for Valeriana officinalis L., an important sedative in herbal medicine. A detailed macroscopic and microscopic account was provided for V. procera Kunth and a comparison was made between the wild and cultivated samples of V. procera Kunth. Macro- and microscopic comparative analyses were performed to differentiate V. procera Kunth from V. officinalis L. and other commercially important Valerian species such as V. jatamansi Jones, Valeriana edulis Nutt, and V. sitchensis Bong.
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isobolographic analysis of the sedative interaction between six central nervous system depressant drugs and Valeriana edulis hydroalcoholic extract in mice
Journal of Pharmacy and Pharmacology, 2005Co-Authors: Martha Ugalde, Ikhlas A. Khan, Ma Eva Gonzaleztrujano, Bharathi Avula, Victoria Reza, Andrés NavarreteAbstract:It has been declared frequently that valerian may potentiate the effect of other central nervous system (CNS) depressant drugs, however there has been a lack of experimental data. We have evaluated the profile of the interactions between the ethanol extract of Valeriana edulis spp procera and six CNS depressant drugs using an exploratory model to test the sedative effect in mice. All the compounds tested showed a dose-dependent sedative effect with the following ED50 values: valerian 181.62, diazepam 1.21, ethanol 1938, pentobarbital 11.86, buspirone 1.04, haloperidol 0.41 and diphenhydramine 17.06 mg kg - 1 . An isobolographic analysis was used to evaluate the sedative interaction of the intraperitoneal co-administration of 1:1 fixed-ratio combination of equi-effective doses of valerian extract with each CNS depressant drug. The ED50 theoretical (Zadd) and experimental (Zexp) for each combination were: valerian + diazepam, Zadd=91.41 mg kg - 1 , Zexp=81.64 mg kg-1; valerian + ethanol, Zadd= 1060.22 mg kg - 1 , Zexp = 687.89 mg kg - 1 ; valerian+pentobarbital, Zadd= 96.74 mg kg - 1 , Zexp= 151.83 mg kg - 1 ; valerian + buspirone, Zadd = 91.33 mg kg - 1 , Zexp = 112.73 mg kg - 1 ; valerian + haloperidol, Zadd= 91.01 mg kg - 1 , Zexp= 91.52mg kg - 1 ; valerian+ diphenhydramine, Zadd= 99.34 mg kg - 1 , Zexp = 123.52 mg kg - 1 . Neither synergistic nor attenuate effects were found in any of the combinations evaluated. We concluded that the valerian extract did not potentiate the sedative effect of commonly prescribed CNS depressant drugs as was expected. The additive effect found through the isobolographic analysis suggested that the sedative effect of V. edulis resulted from the activation of common mechanisms of haloperidol, diazepam, buspirone, pentobarbital, diphenhydramine and ethanol.
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neuropharmacological profile of hydroalcohol extract of Valeriana edulis ssp procera roots in mice
Phytotherapy Research, 2004Co-Authors: Ivan Oliva, Ma Eva Gonzaleztrujano, Jesus Arrieta, Roberto Encisorodriguez, Andrés NavarreteAbstract:Valerian is the common name given to the crude drug consisting of the underground organs of the species Valeriana. Valeriana edulis ssp. procera Meyer is the Mexican valerian. The aim of the present work was to elucidate the neuropharmacological profile of a hydroalcohol extract of Valeriana edulis roots at doses of 100, 300 and 1000 mg/kg in several experimental models. A dose-dependent anticonvulsant and anxiolytic-like effect of V. edulis was demonstrated. In addition, the extract decreased rotarod performance and traction force and prolonged the pentobarbital-induced sleeping time at high doses. Concomitant administration of valerian extract and pentobarbital showed a synergistic effect on motor coordination and traction force in mice. The anxiolytic-like effect of V. edulis was compared with diazepam and with diphenhydramine and doxylamine, the latter in order to consider the H(1)-antihistamine effect as another possibility to explain, at least in part, the central nervous system depressant effect of valerian. These results also underlie the medical and industrial use of this species and allowed the conclusion that the extract of V. edulis has central nervous depressant properties similar to, but with some differences to V. of ficinalis, a very well known species.
