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Ziyin Yang - One of the best experts on this subject based on the ideXlab platform.

  • Uncovering reasons for differential accumulation of Linalool in tea cultivars with different leaf area.
    Food chemistry, 2020
    Co-Authors: Lanting Zeng, Yangyang Xiao, Xiaochen Zhou, Guotai Jian, Jiaming Chen, Jinchi Tang, Ziyin Yang
    Abstract:

    Abstract It is generally proposed that tea cultivars with larger leaves contain more Linalool, an important tea aroma contributor, than ones with smaller leaves. The objective of this study was to confirm the trait and explore the involved reason. Investigation on ten tea cultivars with different leaf areas demonstrated a significant positive correlation between Linalool content and leaf area (R2 = 0.739, p = 0.010). Analysis of metabolite and gene expression level showed that the transform ability of Linalool into Linalool oxides was the key factor. Feeding experiments that supplied tea leaves of different leaf areas with [2H3]Linalool under different light conditions revealed that the larger tea leaves receive more light and are less capable of transformation of Linalool to Linalool oxides, thus leading to Linalool accumulation. This information will advance understanding of the variation of Linalool content in tea varieties and will provide assistance in breeding and screening of high-Linalool tea cultivars.

  • Enzyme Catalytic Efficiencies and Relative Gene Expression Levels of (R)-Linalool Synthase and (S)-Linalool Synthase Determine the Proportion of Linalool Enantiomers in Camellia sinensis var. sinensis.
    Journal of agricultural and food chemistry, 2020
    Co-Authors: Ying Zhou, Rufang Deng, Ziyin Yang
    Abstract:

    Linalool is abundant in tea leaves and contributes greatly to tea aroma. The two isomers of Linalool, (R)-Linalool and (S)-Linalool, exist in tea leaves. Our study found that (R)-Linalool was the minor isomer in nine of Camellia sinensis var. sinensis cultivars. The (R)-Linalool synthase of tea plant CsRLIS was identified subsequently. It is a chloroplast-located protein and specifically catalyzes the formation of (R)-Linalool in vitro and in vivo. CsRLIS was observed to be a stress-responsive gene and caused the accumulation of internal (R)-Linalool during oolong tea manufacture, mechanical wounding, and insect attack. Further study demonstrated that the catalytic efficiency of CsRLIS was much lower than that of (S)-Linalool synthase CsSLIS, which might explain the lower (R)-Linalool proportion in C. sinensis var. sinensis cultivars. The relative expression levels of CsRLIS and CsSLIS may also affect the (R)-Linalool proportions among C. sinensis var. sinensis cultivars. This information will help us understand differential distributions of chiral aroma compounds in tea.

  • formation and emission of Linalool in tea camellia sinensis leaves infested by tea green leafhopper empoasca matsumurasca onukii matsuda
    Food Chemistry, 2017
    Co-Authors: Xin Mei, Ying Zhou, Lanting Zeng, Jinchi Tang, Xiaoyu Liu, Xiaoqin Wang, Fang Dong, Ziyin Yang
    Abstract:

    Famous oolong tea (Oriental Beauty), which is manufactured by tea leaves (Camellia sinensis) infected with tea green leafhoppers, contains characteristic volatile monoterpenes derived from Linalool. This study aimed to determine the formation mechanism of Linalool in tea exposed to tea green leafhopper attack. The tea green leafhopper responsible for inducing the production of characteristic volatiles was identified as Empoasca (Matsumurasca) onukii Matsuda. E. (M.) onukii attack significantly induced the emission of Linalool from tea leaves (p<0.05) as a result of the up-regulation of the Linalool synthases (CsLIS1 and CsLIS2) (p<0.05). Continuous mechanical damage significantly enhanced CsLIS1 and CsLIS2 expression levels and Linalool emission (p<0.05). Therefore, continuous wounding was a key factor causing the formation and emission of Linalool from tea leaves exposed to E. (M.) onukii attack. This information should prove helpful for the future use of stress responses of plant secondary metabolism to improve quality components of agricultural products.

Elaine Elisabetsky - One of the best experts on this subject based on the ideXlab platform.

  • Effects of inhaled Linalool in anxiety, social interaction and aggressive behavior in mice.
    Phytomedicine, 2009
    Co-Authors: Viviane De Moura Linck, A. L. Da Silva, Micheli Figueiró, Elina Bastos Caramão, Paulo Roberto Hrihorowitsch Moreno, Elaine Elisabetsky
    Abstract:

    Aromatherapy uses essential oils (EOs) for several medical purposes, including relaxation. The association between the use of aromas and a decrease in anxiety could be a valuable instrument in managing anxiety in an ever increasing anxiogenic daily life style. Linalool is a monoterpene commonly found as the major volatile component of EOs in several aromatic plant species. Adding to previously reported sedative effects of inhaled Linalool, the aim of this study was to investigate the effects of inhaled Linalool on anxiety, aggressiveness and social interaction in mice. Additionally, we investigated the effects of inhaled Linalool on the acquisition phase of a step-down memory task in mice. Inhaled Linalool showed anxiolytic properties in the light/dark test, increased social interaction and decreased aggressive behavior; impaired memory was only seen the higher dose of Linalool. These results strengthen the suggestion that inhaling Linalool rich essential oils can be useful as a mean to attain relaxation and counteract anxiety.

  • inhaled Linalool induced sedation in mice
    Phytomedicine, 2009
    Co-Authors: Viviane De Moura Linck, Micheli Figueiró, Elina Bastos Caramão, Paulo Roberto Hrihorowitsch Moreno, Adriana Lourenco Da Silva, Angelo L Piato, Ana P Herrmann, Franciele Dupont Birck, Domingos Savio Nunes, Elaine Elisabetsky
    Abstract:

    Linalool is a monoterpene often found as a major component of essential oils obtained from aromatic plant species, many of which are used in traditional medical systems as hypno-sedatives. Psychopharmacological evaluations of Linalool (i.p. and i.c.v.) revealed marked sedative and anticonvulsant central effects in various mouse models. Considering this profile and alleged effects of inhaled lavender essential oil, the purpose of this study was to examine the sedative effects of inhaled Linalool in mice. Mice were placed in an inhalation chamber during 60 min, in an atmosphere saturated with 1% or 3% Linalool. Immediately after inhalation, animals were evaluated regarding locomotion, barbiturate-induced sleeping time, body temperature and motor coordination (rota-rod test). The 1% and 3% Linalool increased (p<0.01) pentobarbital sleeping time and reduced (p<0.01) body temperature. The 3% Linalool decreased (p<0.01) locomotion. Motor coordination was not affected. Hence, Linalool inhaled for 1h seems to induce sedation without significant impairment in motor abilities, a side effect shared by most psycholeptic drugs.

  • Inhaled Linalool-induced sedation in mice.
    Phytomedicine : international journal of phytotherapy and phytopharmacology, 2008
    Co-Authors: Viviane De Moura Linck, Micheli Figueiró, Elina Bastos Caramão, Paulo Roberto Hrihorowitsch Moreno, Adriana Lourenco Da Silva, Angelo L Piato, Ana P Herrmann, Franciele Dupont Birck, Domingos Savio Nunes, Elaine Elisabetsky
    Abstract:

    Linalool is a monoterpene often found as a major component of essential oils obtained from aromatic plant species, many of which are used in traditional medical systems as hypno-sedatives. Psychopharmacological evaluations of Linalool (i.p. and i.c.v.) revealed marked sedative and anticonvulsant central effects in various mouse models. Considering this profile and alleged effects of inhaled lavender essential oil, the purpose of this study was to examine the sedative effects of inhaled Linalool in mice. Mice were placed in an inhalation chamber during 60 min, in an atmosphere saturated with 1% or 3% Linalool. Immediately after inhalation, animals were evaluated regarding locomotion, barbiturate-induced sleeping time, body temperature and motor coordination (rota-rod test). The 1% and 3% Linalool increased (p

  • effects of Linalool on 3h mk801 and 3h muscimol binding in mouse cortical membranes
    Phytotherapy Research, 2001
    Co-Authors: L Silva F Brum, Elaine Elisabetsky, Diogo Onofre Gomes De Souza
    Abstract:

    Linalool is a monoterpene compound reported to be a major component of essential oils of several aromatic species. Several Linalool-producing species are used in traditional medical systems for sedative purposes, including the interruption and prevention of seizures. Previous studies in mice revealed that Linalool modulates glutamatergic (competitive antagonism of L-[(3)H]glutamate binding, delayed intraperitoneal NMDA-induced convulsions and blockade of intracerebroventricular Quin-induced convulsions) and GABAergic transmission (protection against pentylenetetrazol and picrotoxin-induced convulsions). To further clarify the anticonvulsive mechanisms of Linalool, we studied the effects of Linalool on binding of [(3)H]MK801 (NMDA antagonist) and [(3)H]muscimol (GABA(A) agonist) to mouse cortical membranes. Linalool showed a dose dependent non-competitive inhibition of [(3)H]MK801 binding (IC(50) = 2.97 mM) but no effect on [(3)H]muscimol binding. The data suggest that the anticonvulsant mode of action of Linalool includes a direct interaction with the NMDA receptor complex. The data do not, however, support a direct interaction of Linalool with GABA(A) receptors, although changes in GABA-mediated neuronal inhibition or effects on GABA release and uptake cannot be ruled out.

  • Effects of Linalool on glutamate release and uptake in mouse cortical synaptosomes.
    Neurochemical research, 2001
    Co-Authors: L. F. Silva Brum, Diogo O. Souza, Tatiana Emanuelli, Elaine Elisabetsky
    Abstract:

    Linalool, a monoterpene compound prevalent in essential oil of plant species traditionally used as sedatives, has been characterized as anticonvulsant in several experimental models. Linalool inhibits the binding of [3H]glutamate and [3H]dizocilpine to brain cortical membranes, indicating a participation of the glutamatergic transmission its mechanism of action. In this study, we investigated the effects of Linalool on [3H]glutamate release (basal and potassium-stimulated) and [3H]glutamate uptake in mice cortical synaptosomes. Linalool significantly reduced potassium-stimulated glutamate release as well as glutamate uptake, not interfering with basal glutamate release. The data indicates that Linalool may interfere with several relevant elements of the glutamatergic transmission, including detriment of the K+-stimulated glutamate release.

Robert A Raguso - One of the best experts on this subject based on the ideXlab platform.

  • more lessons from Linalool insights gained from a ubiquitous floral volatile
    Current Opinion in Plant Biology, 2016
    Co-Authors: Robert A Raguso
    Abstract:

    Linalool (3,7-dimethyl-1,6-octadien-3-ol) is a common floral volatile with two distinct enantiomers and related metabolites involved in the full spectrum of plant–pollinator interactions. Recent studies reveal a complex interplay between pollinator attraction and plant defense mediated by Linalool and its derivatives, from the smallest (Arabidopsis, Mitella) to the largest (Datura) flowers studied. Accordingly, fig wasps, fungus gnats and moths of all sizes show remarkable electrophysiological, neural and behavioral sensitivity to different enantiomers and quantitative ratios of Linalool in floral bouquets. The diverse functions of Linalool, ranging from toxin to long distance pollinator attractant are discussed in the broader context of floral volatile ecology and evolution.

  • new perspectives in pollination biology floral fragrances a day in the life of a Linalool molecule chemical communication in a plant pollinator system part 1 Linalool biosynthesis in flowering plants
    Plant Species Biology, 1999
    Co-Authors: Robert A Raguso, Eran Pichersky
    Abstract:

    The monoterpene alcohol, Linalool, is present in the soral fragrance of diverse plant families and is attractive to a broad spectrum of pollinators, herbivores and parasitoids. Floral emission of Linalool has evolved de novo in the fragrant, moth-pollinated annual Clarkia breweri (Gray) Greene (Onagraceae) through a combination of up-regulation and ectopic expression of its biosynthetic enzyme, Linalool synthase (LIS), in conjunction with allometric size increases in all soral organs. Linalool synthase activity and Linalool emissions are 1000-fold lower in a sibling species, C. concinna (Fischer & Meyer) Greene, that is diurnally pollinated. Linalool synthase expression is spatially and temporally regulated during C. breweri sower development, immediately precedes free Linalool emission and is absent from nonsoral tissues. Its activity is highest in the style, but most of the Linalool product appears to be converted to the pyranoid and furanoid Linalool oxides. The LIS structural gene is a member of the terpene synthase gene family, sharing sequence identity with two discrete classes, represented by limonene synthase (LMS) and copalyl pyrophosphate synthase (CPS). Genetic crosses between C. breweri and C. concinna indicate that strong Linalool emission segregates as a dominant mendelian trait, whereas the inheritance of Linalool oxide formation is more complex, suggesting epistatic biosynthetic pathway interactions. We discuss areas for future research, including comparative studies of Linalool biosynthesis in different plant families, entrainment of Linalool emission to nocturnal circadian rhythms and the induction of vegetative Linalool as an indirect herbivore defense.

  • New Perspectives in Pollination Biology: Floral Fragrances. A day in the life of a Linalool molecule: Chemical communication in a plant‐pollinator system. Part 1: Linalool biosynthesis in flowering plants
    Plant Species Biology, 1999
    Co-Authors: Robert A Raguso, Eran Pichersky
    Abstract:

    The monoterpene alcohol, Linalool, is present in the soral fragrance of diverse plant families and is attractive to a broad spectrum of pollinators, herbivores and parasitoids. Floral emission of Linalool has evolved de novo in the fragrant, moth-pollinated annual Clarkia breweri (Gray) Greene (Onagraceae) through a combination of up-regulation and ectopic expression of its biosynthetic enzyme, Linalool synthase (LIS), in conjunction with allometric size increases in all soral organs. Linalool synthase activity and Linalool emissions are 1000-fold lower in a sibling species, C. concinna (Fischer & Meyer) Greene, that is diurnally pollinated. Linalool synthase expression is spatially and temporally regulated during C. breweri sower development, immediately precedes free Linalool emission and is absent from nonsoral tissues. Its activity is highest in the style, but most of the Linalool product appears to be converted to the pyranoid and furanoid Linalool oxides. The LIS structural gene is a member of the terpene synthase gene family, sharing sequence identity with two discrete classes, represented by limonene synthase (LMS) and copalyl pyrophosphate synthase (CPS). Genetic crosses between C. breweri and C. concinna indicate that strong Linalool emission segregates as a dominant mendelian trait, whereas the inheritance of Linalool oxide formation is more complex, suggesting epistatic biosynthetic pathway interactions. We discuss areas for future research, including comparative studies of Linalool biosynthesis in different plant families, entrainment of Linalool emission to nocturnal circadian rhythms and the induction of vegetative Linalool as an indirect herbivore defense.

  • floral scent production in clarkia onagraceae i localization and developmental modulation of monoterpene emission and Linalool synthase activity
    Plant Physiology, 1994
    Co-Authors: Eran Pichersky, Robert A Raguso, Efraim Lewinsohn, Rodney Croteau
    Abstract:

    The flowers of many plants emit volatile compounds as a means of attracting pollinators. We have previously shown that the strong, sweet fragrance of Clarkia breweri (Onagraceae), an annual plant native to California, consists of approximately 8 to 12 volatile compounds[mdash]three monoterpenes and nine benzoate derivatives (R.A. Raguso and E. Pichersky [1994] Plant Syst Evol [in press]). Here we report that the monoterpene alcohol Linalool is synthesized and emitted mostly by petals but to a lesser extent also by the pistil and stamens. Two Linalool oxides are produced and emitted almost exclusively by the pistil. These three monoterpenes are first discernible in mature unopened buds, and their tissue levels are highest during the first 2 to 3 d after anthesis. Levels of emission by the different floral parts throughout the life span of the flower were correlated with levels of these monoterpenes in the respective tissues, suggesting that these monoterpenes are emitted soon after their synthesis. Activity of Linalool synthase, an enzyme that converts the ubiquitous C10 isoprenoid intermediate geranyl pyrophosphate to Linalool, was highest in petals, the organ that emits most of the Linalool. However, Linalool synthase activity on a fresh weight basis was highest in stigma and style (i.e. the pistil). Most of the Linalool produced in the pistil is apparently converted into Linalool oxides. Lower levels (0.1%) of monoterpene emission and Linalool synthase activity are found in the stigma of Clarkia concinna, a nonscented relative of C. breweri, suggesting that monoterpenes may have other functions in the flower in addition to attracting pollinators.

Chunlei Yue - One of the best experts on this subject based on the ideXlab platform.

  • Combinatorial Modulation of Linalool Synthase and Farnesyl Diphosphate Synthase for Linalool Overproduction in Saccharomyces cerevisiae.
    Journal of agricultural and food chemistry, 2021
    Co-Authors: Pingping Zhou, Xin Fang, Chunlei Yue
    Abstract:

    Linalool, as a fragrant monoterpene, is an important feedstock for food, pharmaceuticals, and cosmetics industries. Although our previous study had significantly increased Linalool production by the directed evolution of Linalool synthase and overexpression of the whole mevalonate pathway genes, the engineered yeast strain suffered from dramatically reduced biomass. Herein, a stress-free Linalool-producing yeast cell factory was constructed by the combinational regulation of Linalool synthase and farnesyl diphosphate synthase instead of multienzyme overexpression. First, the expression level of Linalool synthase was successfully enhanced by introducing a N-terminal SKIK tag, which improved Linalool production by 3.3-fold. Subsequently, the modular assembly of Linalool synthase and dominant negative farnesyl diphosphate synthase via short peptide tags efficiently converted geranyl pyrophosphate to Linalool. Additional downregulation of the native farnesyl diphosphate synthase led to the highest reported Linalool production (80.9 mg/L) in yeast. This combinatorial modulation strategy may also be applied to the production of other high-value monoterpenes.

  • Improved Linalool production in Saccharomyces cerevisiae by combining directed evolution of Linalool synthase and overexpression of the complete mevalonate pathway
    Biochemical Engineering Journal, 2020
    Co-Authors: Pingping Zhou, Chunlei Yue
    Abstract:

    Abstract With special fragrance and various biological properties, Linalool has wide applications in food, pharmaceuticals and cosmetics industries. Microbial biosynthesis has become a promising approach to Linalool production, however its efficiency is limited by the limited precursor supply and poor efficiency of Linalool synthase. With the goal of enhancing heterologous Linalool production in Saccharomyces cerevisiae, protein engineering and metabolic engineering were simultaneously employed to solve these bottlenecks. Linalool-producing yeast was first constructed by introduction of t67OMcLIS selected out from a collection of Linalool synthases. The efficiency of Linalool biosynthesis was then improved by strengthening the supply of geranyl pyrophosphate (GPP) as precursor via overexpression of the complete mevalonate (MVA) pathway and a GPP synthase variant. To accelerate the conversion of the accumulated GPP to Linalool, t67OMcLIS was engineered by means of directed evolution after development of a competition-based color-indicated high-throughput screening method. Expression of the t67OMcLIS variant in the engineered S. cerevisiae with enhanced precursor supply yielded 53.14 mg/L of Linalool in biphasic shake-flask culture. This study delivered an efficient Linalool-producing yeast cell factory and meanwhile provided efficient strategies for biosynthesis of other valuable monoterpenes.

Jingwen Zhou - One of the best experts on this subject based on the ideXlab platform.

  • enhanced s Linalool production by fusion expression of farnesyl diphosphate synthase and Linalool synthase in saccharomyces cerevisiae
    Journal of Applied Microbiology, 2016
    Co-Authors: Yu Deng, Mingxue Sun, Jingwen Zhou
    Abstract:

    AIMS In order to improve the availability of geranyl diphosphate (GPP) in the mevalonate pathway for enhancing (S)-Linalool production in Saccharomyces cerevisiae. METHODS AND RESULTS A (S)-Linalool synthase (LIS): AaLS1 from Actinidia arguta was coexpressed with FPPS with different peptide linkers to redirect the flux from geranyl diphosphate (GPP) to (S)-Linalool production in S. cerevisiae. The strain with the best peptide linker ((GGGGS)3 ), produced 101·55 ± 2·97 μg l(-1) (S)-Linalool, a 69·7% increase compared to those with two independent LIS and FPPS expressed. In a 3-l fermenter, the (S)-Linalool titre was further improved to 240·64 ± 5·31 μg l(-1) . CONCLUSIONS The results demonstrate that the fusion proteins catalysing consecutive steps in a metabolic pathway significantly improved the (S)-Linalool production with GPP as precursor. SIGNIFICANCE AND IMPACT OF THE STUDY The fusion protein strategy co-expressing AaLS1 and FPPS, assembled with a long peptide linker made S. cerevisiae produced the highest reported (S)-Linalool titre to date.

  • Enhanced (S)‐Linalool production by fusion expression of farnesyl diphosphate synthase and Linalool synthase in Saccharomyces cerevisiae
    Journal of Applied Microbiology, 2016
    Co-Authors: Yu Deng, Sha Xu, Jingwen Zhou
    Abstract:

    AIMS: In order to improve the availability of geranyl diphosphate (GPP) in the mevalonate pathway for enhancing (S)-Linalool production in Saccharomyces cerevisiae. METHODS AND RESULTS: A (S)-Linalool synthase (LIS): AaLS1 from Actinidia arguta was coexpressed with FPPS with different peptide linkers to redirect the flux from geranyl diphosphate (GPP) to (S)-Linalool production in S. cerevisiae. The strain with the best peptide linker ((GGGGS)3 ), produced 101·55 ± 2·97 μg l(-1) (S)-Linalool, a 69·7% increase compared to those with two independent LIS and FPPS expressed. In a 3-l fermenter, the (S)-Linalool titre was further improved to 240·64 ± 5·31 μg l(-1) . CONCLUSIONS: The results demonstrate that the fusion proteins catalysing consecutive steps in a metabolic pathway significantly improved the (S)-Linalool production with GPP as precursor. SIGNIFICANCE AND IMPACT OF THE STUDY: The fusion protein strategy co-expressing AaLS1 and FPPS, assembled with a long peptide linker made S. cerevisiae produced the highest reported (S)-Linalool titre to date.