The Experts below are selected from a list of 249 Experts worldwide ranked by ideXlab platform
Xinmiao Liang - One of the best experts on this subject based on the ideXlab platform.
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characterization of tropane and cinnamamide alkaloids from Scopolia tangutica by high performance liquid chromatography with quadrupole time of flight tandem mass spectrometry
IEEE Journal of Solid-state Circuits, 2019Co-Authors: Nana Du, Weijia Zhou, Han Zhou, Xinmiao LiangAbstract:: Scopolia tangutica is a traditional Chinese medicine used for antispasmodic, anesthesia, analgesia, and sedation. Its medicinal activity is associated to alkaloid constituents, including tropane and cinnamamide types. Low content of alkaloids in plant makes them difficult to be isolated and identified. The present work developed an effective method to quickly characterize alkaloids from Scopolia tangutica by high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry. Thirteen reference compounds were studied for their fragmentation pathways, including five tropane alkaloids and eight cinnamamide ones. Alkaloid constituent was analyzed by an optimized high-performance liquid chromatography method and mass spectrometry analysis to achieve systematic characterization of alkaloids from Scopolia tangutica. As a result, 53 compounds were identified, including 21 tropane alkaloids (eight new ones), 18 caffeoyl ones (ten new ones) and 14 dicaffeoyl ones (seven new ones). It was important to provide rich information in phytochemical study and structure-guided isolation of important compounds from this plant.
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discovery of new muscarinic acetylcholine receptor antagonists from Scopolia tangutica
Scientific Reports, 2017Co-Authors: Nana Du, Han Zhou, Xinmiao Liang, Xiuli Zhang, Jixia Wang, Jianqiang Zhao, Jian HeAbstract:Scopolia tangutica (S. tangutica) is a traditional Chinese medicinal plant used for antispasmodics, anesthesia, analgesia and sedation. Its pharmacological activities are mostly associated with the antagonistic activity at muscarinic acetylcholine receptors (mAchRs) of several known alkaloids such as atropine and scopolamine. With our recent identification of four hydroxycinnamic acid amides from S. tangutica, we hypothesized that this plant may contain previously unidentified alkaloids that may also contribute to its in vivo effect. Herein, we used a bioassay-guided multi-dimension separation strategy to discover novel mAchR antagonists from S. tangutica. The core of this approach is to use label-free cell phenotypic assay to first identify active fractions, and then to guide purification of active ligands. Besides four tropanes and six cinnamic acid amides that have been previously isolated from S. tangutica, we recently identified two new tropanes, one new cinnamic acid amide, and nine other compounds. Six tropane compounds purified from S. tangutica for the first time were confirmed to be competitive antagonists of muscarinic receptor 3 (M3), including the two new ones 8 and 12 with IC50 values of 1.97 μM and 4.47 μM, respectively. Furthermore, the cinnamic acid amide 17 displayed 15-fold selectivity for M1 over M3 receptors. These findings will be useful in designing lead compounds for mAchRs and elucidating mechanisms of action of S. tangutica.
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amide alkaloids from Scopolia tangutica
Planta Medica, 2014Co-Authors: Zhen Long, Yan Zhang, Lien Wang, Xiuli Zhang, Shisheng Wang, Zhiwei Wang, Olivier Civelli, Xinmiao LiangAbstract:Four new hydroxycinnamic acid amides, scotanamines A–D (1–4), and seven known alkaloids, including N 1,N 10-di-dihydrocaffeoylspermidine (5), scopolamine (6), anisodamine (7), hyoscyamine (8), anisodine (9), caffeoylputrescine (10), and N 1-caffeoyl-N 3-dihydrocaffeoylspermidine (11), were obtained from the roots of Scopolia tangutica. The present study represents the first recognition of hydroxycinnamic acid amides containing putrescine or spermidine in S. tangutica. Compound 1, in particular, contains a moiety resulting from the condensation of nortropinone and putrescine. Compound 2 exhibited moderate agonist activity at the µ-opioid receptor (EC50 = 7.3 µM). Compound 2 was tested in vivo and induced analgesia in mice. The analgesic effect was recorded using the tail-flick assay and was reversed by naloxone.
Nana Du - One of the best experts on this subject based on the ideXlab platform.
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characterization of tropane and cinnamamide alkaloids from Scopolia tangutica by high performance liquid chromatography with quadrupole time of flight tandem mass spectrometry
IEEE Journal of Solid-state Circuits, 2019Co-Authors: Nana Du, Weijia Zhou, Han Zhou, Xinmiao LiangAbstract:: Scopolia tangutica is a traditional Chinese medicine used for antispasmodic, anesthesia, analgesia, and sedation. Its medicinal activity is associated to alkaloid constituents, including tropane and cinnamamide types. Low content of alkaloids in plant makes them difficult to be isolated and identified. The present work developed an effective method to quickly characterize alkaloids from Scopolia tangutica by high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry. Thirteen reference compounds were studied for their fragmentation pathways, including five tropane alkaloids and eight cinnamamide ones. Alkaloid constituent was analyzed by an optimized high-performance liquid chromatography method and mass spectrometry analysis to achieve systematic characterization of alkaloids from Scopolia tangutica. As a result, 53 compounds were identified, including 21 tropane alkaloids (eight new ones), 18 caffeoyl ones (ten new ones) and 14 dicaffeoyl ones (seven new ones). It was important to provide rich information in phytochemical study and structure-guided isolation of important compounds from this plant.
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discovery of new muscarinic acetylcholine receptor antagonists from Scopolia tangutica
Scientific Reports, 2017Co-Authors: Nana Du, Han Zhou, Xinmiao Liang, Xiuli Zhang, Jixia Wang, Jianqiang Zhao, Jian HeAbstract:Scopolia tangutica (S. tangutica) is a traditional Chinese medicinal plant used for antispasmodics, anesthesia, analgesia and sedation. Its pharmacological activities are mostly associated with the antagonistic activity at muscarinic acetylcholine receptors (mAchRs) of several known alkaloids such as atropine and scopolamine. With our recent identification of four hydroxycinnamic acid amides from S. tangutica, we hypothesized that this plant may contain previously unidentified alkaloids that may also contribute to its in vivo effect. Herein, we used a bioassay-guided multi-dimension separation strategy to discover novel mAchR antagonists from S. tangutica. The core of this approach is to use label-free cell phenotypic assay to first identify active fractions, and then to guide purification of active ligands. Besides four tropanes and six cinnamic acid amides that have been previously isolated from S. tangutica, we recently identified two new tropanes, one new cinnamic acid amide, and nine other compounds. Six tropane compounds purified from S. tangutica for the first time were confirmed to be competitive antagonists of muscarinic receptor 3 (M3), including the two new ones 8 and 12 with IC50 values of 1.97 μM and 4.47 μM, respectively. Furthermore, the cinnamic acid amide 17 displayed 15-fold selectivity for M1 over M3 receptors. These findings will be useful in designing lead compounds for mAchRs and elucidating mechanisms of action of S. tangutica.
Myungsuk Choi - One of the best experts on this subject based on the ideXlab platform.
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production of tropane alkaloids during de differentiation of Scopolia parviflora calli
Journal of Natural Products, 2010Co-Authors: Seung Mi Kang, Won Kyun Choi, Mi Jin Jeong, Chandrakant S Karigar, Myungsuk ChoiAbstract:The production of tropane alkaloids during differentiation and de-differentiation of Scopolia parviflora calli was studied. Tropane alkaloid production drastically decreased during calli de-differentiation. Scopolamine (1) production decreased after 10 days of culture, whereas that of hyoscyamine (2) decreased during de-differentiation of root to calli. The production of 1 was enhanced in calli undergoing differentiation to shoot after 60 days of culture, reaching a maximum by 80 days. However, production of hyoscyamine in regenerated plants was lower. The expression level of hyoscyamine 6β-hydroxylase (H6H), a key biosynthetic enzyme for tropane alkaloids, was significantly increased in 4-week-old calli. This study suggests that the biosynthesis of tropane alkaloids is regulated inversely in de-differentiating Scopolia parviflora calli.
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High frequency plant regeneration and accumulation of tropane alkaloids in regenerated plants of Scopolia parviflora
In Vitro Cellular & Developmental Biology - Plant, 2008Co-Authors: Youngmin Kang, Hyun Shik Moon, D. Theertha Prasad, Myungsuk ChoiAbstract:An efficient in vitro plant regeneration system was established from callus culture of Scopolia parviflora . Callus was induced from adventitious roots on B5 medium with 0.45–9.04 μM 2,4-dichlorophenoxyacetic acid (2,4-D). In vitro plantlet regeneration was achieved on B5 medium supplemented with 44.38 μM benzyladenine (BA), 3% sucrose, and 0.38% gelrite. Plantlets were transplanted to artificial soil and grown to maturity successfully in a greenhouse. The tropane alkaloid contents in regenerated plants were analyzed using high-performance liquid chromatography (HPLC), and were found to be higher than those of adventitious roots, native growing plants, and acclimated plants. Regenerated plants from organogenic callus cultures produced a greater amount of tropane alkaloids.
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production of monoclonal antibody about specific key enzyme of hyoscyamine 6 beta hydroxylase h6h in Scopolia parviflora
The Korean Journal of Medicinal Crop Science, 2004Co-Authors: Youngmin Kang, Seung Mi Kang, Heeyoung Jung, Myungsuk ChoiAbstract:Total RNAs were isolated from cultured roots of Scopolia parviflora, RNA was obtained through the mRNA purification, cDNA library of Hnh6h was constructed. Recombinant baculoviruses in Spodoptera frugiperda (Sf) cells were constructed by use of the transfer vector pBacPAK, which has the AcNPV sequence under the polyhedrin promoter. The expression vector carrying Hnh6h gene was transferred to S. parviflora and obtained transgenic hairy root lines. Our results confirmed the over expression of the H6H protein was used by anti-pBacPAK about cDNAs of S. parviflora. This study will served for production of tropane alkaloids by metabolic engineering.
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enhanced production of scopolamine by bacterial elicitors in adventitious hairy root cultures of Scopolia parviflora
Enzyme and Microbial Technology, 2003Co-Authors: Heeyoung Jung, Seung Mi Kang, Youngmin Kang, Minjung Kang, Jungdong Bahk, Jaekyung Yang, Myungsuk ChoiAbstract:In an attempt to increase productivity, the effect of elicitation on tropane alkaloids (TA) biosynthesis was studied in adventitious hairy root cultures of Scopolia parviflora. Two Gram-positive strains and one Gram-negative strain of bacteria were used as biotic elicitors. The raw bacterial elicitors affected the tropane alkaloid profile by increasing the scopolamine concentration, while the autoclaved bacterial elicitors produced similar effects on the control. The conversion ratio of hyoscyamine to scopolamine was increased following elicitation using raw bacterial elicitors. The bacterial elicitor inhibited the expression of H6H (hyoscyamine 6β-hydoxylase) whereas the expression of PMT (putrescine N-methyltransferase) was raised by elicitation. These results have important implications for the large-scale production of tropane alkaloids.
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selection of optimal biotic elicitor on tropane alkaloid production of hairy roots in Scopolia parviflora nakai
The Korean Journal of Medicinal Crop Science, 2003Co-Authors: Heeyoung Jung, Seung Mi Kang, Youngmin Kang, Jaekyung Yang, Younggwan Chung, Myungsuk ChoiAbstract:ScopoIamine and hyoscyamine which belong to tropane alkaloids are the pharmaceutically valuable anticholinergic drugs. In order to increase the productivities, the effects of elicitation were investigated during hairy root cultures of Scopolia. parviflora. Biotic elicitors originated from 3 fungi and 1 yeast were prepared as homogenate and supernatant and added to 3-week-old cultures. Both of homogenate and supernatant of Candida albicans elicitors increased the scopolamine production. The production of hyoscyamine was enhanced by homogenate of Fusarium solani and supernatant of C. albicans. Most of the other fungal elicitors were also improved on the tropane alkaloid production compared to non-treatment. Among the elicitors tested, C. albicans was proved the optimal biotic elicitor on tropane alkaloids production. These results will be served mass production of tropane alkaloids by large-scale production.
Patrick Saindrenan - One of the best experts on this subject based on the ideXlab platform.
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over expression of a scopoletin glucosyltransferase in nicotiana tabacum leads to precocious lesion formation during the hypersensitive response to tobacco mosaic virus but does not affect virus resistance
Plant Molecular Biology, 2004Co-Authors: Patrick Saindrenan, Claire M M Gachon, Rachel BaltzAbstract:Nicotiana tabacum Togt encodes a scopoletin glucosyltransferase (UDPglucose:scopoletin O-β-D-glucosyltransferase, EC 2.4.1.128) known to act in vitro on many different substrates including the 6-methoxy-7-hydroxy- coumarin scopoletin. This phenolic compound accumulates in vast amounts, essentially in its glucosylated form scopolin, in tobacco during the hypersensitive response (HR) to tobacco mosaic virus (TMV). To identify the physiological role of this pathogen-inducible UDP-Glc glucosyltransferase (UGT), we generated TOGT over-expressing transgenic plants. Although no endogenous scopoletin or scopolin could be detected before infection, the accumulation of both the aglycone and the glucoside was found to be 2-fold higher in transgenic plants after inoculation with TMV than in wild-type plants. Scopoletin UGT activity in plants over-expressing Togt was significantly higher during the HR than in control plants. This up-regulated activity was associated with a strong increase of the bright blue fluorescence surrounding the HR-necrotic lesions under UV light, which is known to correlate with scopoletin and scopolin abundance. Necrosis appeared sooner in transgenic plants and lesions developed faster, suggesting an accelerated HR. Unexpectedly, the viral content in each lesion was not significantly different in transgenic and in wild-type plants. These results are discussed in relation to the role of TOGT as the major UDP-Glc: scopoletin glucosyltransferase and to the importance of scopoletin accumulation during the HR.
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downregulation of a pathogen responsive tobacco udp glc phenylpropanoid glucosyltransferase reduces scopoletin glucoside accumulation enhances oxidative stress and weakens virus resistance
The Plant Cell, 2002Co-Authors: Julie Chong, Bernard Fritig, Rachel Baltz, Roland Beffa, Corinne Schmitt, Patrick SaindrenanAbstract:Plant UDP-Glc:phenylpropanoid glucosyltransferases (UGTs) catalyze the transfer of Glc from UDP-Glc to numerous substrates and regulate the activity of compounds that play important roles in plant defense against pathogens. We previously characterized two tobacco salicylic acid– and pathogen-inducible UGTs (TOGTs) that act very efficiently on the hydroxycoumarin scopoletin and on hydroxycinnamic acids. To identify the physiological roles of these UGTs in plant defense, we generated TOGT-depleted tobacco plants by antisense expression. After inoculation with Tobacco mosaic virus (TMV), TOGT-inhibited plants exhibited a significant decrease in the glucoside form of scopoletin (scopolin) and a decrease in scopoletin UGT activity. Unexpectedly, free scopoletin levels also were reduced in TOGT antisense lines. Scopolin and scopoletin reduction in TOGT-depleted lines resulted in a strong decrease of the blue fluorescence in cells surrounding TMV lesions and was associated with weakened resistance to infection with TMV. Consistent with the proposed role of scopoletin as a reactive oxygen intermediate (ROI) scavenger, TMV also triggered a more sustained ROI accumulation in TOGT-downregulated lines. Our results demonstrate the involvement of TOGT in scopoletin glucosylation in planta and provide evidence of the crucial role of a UGT in plant defense responses. We propose that TOGT-mediated glucosylation is required for scopoletin accumulation in cells surrounding TMV lesions, where this compound could both exert a direct antiviral effect and participate in ROI buffering.
Weijia Zhou - One of the best experts on this subject based on the ideXlab platform.
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characterization of tropane and cinnamamide alkaloids from Scopolia tangutica by high performance liquid chromatography with quadrupole time of flight tandem mass spectrometry
IEEE Journal of Solid-state Circuits, 2019Co-Authors: Nana Du, Weijia Zhou, Han Zhou, Xinmiao LiangAbstract:: Scopolia tangutica is a traditional Chinese medicine used for antispasmodic, anesthesia, analgesia, and sedation. Its medicinal activity is associated to alkaloid constituents, including tropane and cinnamamide types. Low content of alkaloids in plant makes them difficult to be isolated and identified. The present work developed an effective method to quickly characterize alkaloids from Scopolia tangutica by high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry. Thirteen reference compounds were studied for their fragmentation pathways, including five tropane alkaloids and eight cinnamamide ones. Alkaloid constituent was analyzed by an optimized high-performance liquid chromatography method and mass spectrometry analysis to achieve systematic characterization of alkaloids from Scopolia tangutica. As a result, 53 compounds were identified, including 21 tropane alkaloids (eight new ones), 18 caffeoyl ones (ten new ones) and 14 dicaffeoyl ones (seven new ones). It was important to provide rich information in phytochemical study and structure-guided isolation of important compounds from this plant.
