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Robert Anton - One of the best experts on this subject based on the ideXlab platform.
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Effects of two monoterpene esters, Valtrate and didroValtrate, isolated from Valeriana wallichii, on the ultrastructure of hepatoma cells in culture
Phytotherapy Research, 1993Co-Authors: C. Keochanthala-bounthanh, M. Haag-berrurier, Jean-paul Beck, Robert AntonAbstract:The action of two monoterpene esters isolated from Valeriana wallichii D.C., Valtrate and didroValtrate, has been studied on the ultrastructure of HTC hepatoma cells in culture. These two compounds are cytoxic and inhibit the synthesis of DNA and protein in tumour cells. The study using scanning and transmission electron microscopy showed that, prior to cell death, the two compounds cause the disappearance of membrane microvilli, a large distension of the endoplasmic reticulum and a marked condensation of the mitochondria. Furthermore, Valtrate rapidly leads to the rounding and detachment of cells cultivated in layers whereas, in the presence of didroValtrate, the cells remain spread out and tightly attached to the support, even after treatment with trypsin.
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Effects of Thiol Compounds versus the Cytotoxicity of Valepotriates on Cultured Hepatoma Cells
Planta Medica, 1990Co-Authors: C. Keochanthala-bounthanh, M. Haag-berrurier, J.p. Beck, Robert AntonAbstract:The antagonistic activity of various thiol compounds versus the cytotoxic effects of Valtrate and didroValtrate has been evaluated on cultured hepatoma cells. Compounds with free SH groups like cysteine, mercaptoethanol, dithioerythritol, and glutathione were able to suppress the cytotoxicity of the valepotriates in a dose-dependent way, whereas compounds with blocked SH groups did not antagonize these toxic effects. The possible interactions between the valepotriates and thiol compounds are discussed.
Gilsane Lino Von Poser - One of the best experts on this subject based on the ideXlab platform.
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In Vitro Effect of Valepotriates Isolated from Valeriana glechomifolia on Rat P-Type ATPases
Planta medica, 2011Co-Authors: Gustavo M. Bettero, Luisa De Andrade Salles, Renata M. Rosário Figueira, Gilsane Lino Von Poser, Stela Maris Kuze Rates, François Noël, Luis Eduardo M. QuintasAbstract:Valepotriates are iridoids found in variable amounts in Valerianaceae and might be among the bioactive compounds which confer anxiolytic properties to the Valeriana species. On the other hand, unspecific cytotoxicity has also been described. Presently, however, no particular molecular target has been defined for these compounds. Here we studied the effect of Valtrate, aceValtrate, and 1- β-aceValtrate isolated from Valeriana glechomifolia on the enzymatic activity of rat P-type ATPases. Valepotriates did not affect rat skeletal muscle sarco/endoplasmic reticulum Ca²⁺-ATPase (SERCA) activity at the highest concentration used (100 µM). In contrast, the same concentration inhibited roughly half of the total H⁺/K⁺-ATPase activity from rat gastric epithelium (Valtrate 54.6 ± 3.2 %, aceValtrate 60.7 ± 7.3 %, 1- β-aceValtrate 50.2 ± 3.1 %; mean ± SEM, n = 3-5). Finally, these substances showed the highest inhibitory potency toward Na⁺/K⁺-ATPase, and the inhibition curves obtained provided a similar IC₅₀ (in µM) for rat kidney α1 isoform (Valtrate 21.2, aceValtrate 22.8, 1- β-aceValtrate 24.4) and brain hemispheres α2/ α3 isoforms (Valtrate 19.4, aceValtrate 42.3, 1- β-aceValtrate 38.3). Our results suggest that P-type ATPases are differentially inhibited by valepotriates and that Na⁺/K⁺-ATPase might be one of their molecular targets in vivo.
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Quantitative determination of valepotriates from Valeriana native to South Brazil.
Planta medica, 2002Co-Authors: Andreia Loviane Silva, Sandra Beatriz Rech, Gilsane Lino Von PoserAbstract:Valtrate, DIA-Valtrate, aceValtrate, 1-beta-aceValtrate and didroValtrate have been quantitatively estimated by reversed-phase HPLC in the leaves, flowers, stems and roots of Valeriana glechomifolia Meyer, V. catharinensis Graebn., V. chamaedryfolia Cham. & Schltdl., V. eichleriana (C.A.Mull.) Graebn., V. polysthachya Smith, V. scandens L., V. eupatoria Sobral, V. salicariifolia Vahl and V. tajuvensis Sobral. All plants presented valepotriates being V. glechomifolia the richest one, followed by V. eupatoria, V. eichleriana and V. tajuvensis.
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Valeriana glechomifolia: in vitro propagation and production of valepotriates
Plant Science, 2002Co-Authors: Luisa De Andrade Salles, Gilsane Lino Von Poser, Andréa Loviane Silva, Arthur Germano Fett-neto, Sandra Beatriz RechAbstract:A practical method for the multiplication of Valeriana glechomifolia Meyer was developed and valepotriates synthesis in the plantlets was studied. Axillary buds and shoot tips were cultured in 0.3/ Murashige and Skoog basal medium supplemented with either 0.4 mg l 1 of BAP or without plant growth regulators. The cultured segments grew on both media and produced roots after 3/4 weeks. The dienic valepotriates Valtrate, DIA-Valtrate, aceValtrate and 1-b-aceValtrate and the monoenic valepotriate didroValtrate have each been quantitated in the leaves, stems and roots of the micropropagated plantlets and compared with the field-grown plants by reversed-phase HPLC. Plantlets grown on growth regulator-free medium displayed higher valepotriate contents (ranging from 3.54% in stems to 0.98% in leaves) than with the addition of BAP (from 1.22% in leaves to 0.36% in stems) and field-grown plants (from 0.89% in stems to 0.10% in inflorescences). In most cases, aceValtrate was the most abundant compound. # 2002 Elsevier Science Ireland Ltd. All rights reserved.
C. Keochanthala-bounthanh - One of the best experts on this subject based on the ideXlab platform.
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Effects of two monoterpene esters, Valtrate and didroValtrate, isolated from Valeriana wallichii, on the ultrastructure of hepatoma cells in culture
Phytotherapy Research, 1993Co-Authors: C. Keochanthala-bounthanh, M. Haag-berrurier, Jean-paul Beck, Robert AntonAbstract:The action of two monoterpene esters isolated from Valeriana wallichii D.C., Valtrate and didroValtrate, has been studied on the ultrastructure of HTC hepatoma cells in culture. These two compounds are cytoxic and inhibit the synthesis of DNA and protein in tumour cells. The study using scanning and transmission electron microscopy showed that, prior to cell death, the two compounds cause the disappearance of membrane microvilli, a large distension of the endoplasmic reticulum and a marked condensation of the mitochondria. Furthermore, Valtrate rapidly leads to the rounding and detachment of cells cultivated in layers whereas, in the presence of didroValtrate, the cells remain spread out and tightly attached to the support, even after treatment with trypsin.
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Effects of Thiol Compounds versus the Cytotoxicity of Valepotriates on Cultured Hepatoma Cells
Planta Medica, 1990Co-Authors: C. Keochanthala-bounthanh, M. Haag-berrurier, J.p. Beck, Robert AntonAbstract:The antagonistic activity of various thiol compounds versus the cytotoxic effects of Valtrate and didroValtrate has been evaluated on cultured hepatoma cells. Compounds with free SH groups like cysteine, mercaptoethanol, dithioerythritol, and glutathione were able to suppress the cytotoxicity of the valepotriates in a dose-dependent way, whereas compounds with blocked SH groups did not antagonize these toxic effects. The possible interactions between the valepotriates and thiol compounds are discussed.
Sandra Beatriz Rech - One of the best experts on this subject based on the ideXlab platform.
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Improved nutrient medium for biomass and valepotriate production in extended period stock cultures of Valeriana glechomifolia
In Vitro Cellular & Developmental Biology - Plant, 2008Co-Authors: Natasha Maurmann, Sandra Beatriz Rech, Arthur Germano Fett-netoAbstract:Valeriana glechomifolia , a southern Brazilian endemic species commonly known as Valerian, accumulates the bioactive terpene derivatives valepotriates in all of its organs. In vitro growth of V. glechomifolia on solid Murashige and Skoog (MS) without phytohormones at full, 75% (MS 75), or on a modified formulation (M Δ) was compared in stock cultures kept for up to 9 mo. without subculture. Changes in biomass accumulation, development of roots and shoots, and the production of the valepotriates aceValtrate, didroValtrate, and Valtrate were monthly evaluated. The highest biomass accumulation and root development was observed in plants grown on M Δ, whereas better leaf development was detected in M-Δ- and MS-medium-grown plants after 8 and 9 mo. of culture, respectively. Maximal didroValtrate and Valtrate yields were observed in M-Δ-grown plants harvested after 5 and 6 mo. of culture, respectively, whereas aceValtrate concentration was highest on M-Δ- and MS-75-grown plants after 7 mo. of culture. Plants grown for 6 mo. without subculture in M Δ were successfully propagated, showing stable growth and valepotriate yields three- to sixfold higher that those observed in field-grown plants. The results showed a positive effect of combined moderate reduction in salt concentration and increases in selected micronutrients and myo-inositol amounts on both growth and valepotriate yields of extended period stock cultures of V. glechomifolia .
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Quantitative determination of valepotriates from Valeriana native to South Brazil.
Planta medica, 2002Co-Authors: Andreia Loviane Silva, Sandra Beatriz Rech, Gilsane Lino Von PoserAbstract:Valtrate, DIA-Valtrate, aceValtrate, 1-beta-aceValtrate and didroValtrate have been quantitatively estimated by reversed-phase HPLC in the leaves, flowers, stems and roots of Valeriana glechomifolia Meyer, V. catharinensis Graebn., V. chamaedryfolia Cham. & Schltdl., V. eichleriana (C.A.Mull.) Graebn., V. polysthachya Smith, V. scandens L., V. eupatoria Sobral, V. salicariifolia Vahl and V. tajuvensis Sobral. All plants presented valepotriates being V. glechomifolia the richest one, followed by V. eupatoria, V. eichleriana and V. tajuvensis.
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Valeriana glechomifolia: in vitro propagation and production of valepotriates
Plant Science, 2002Co-Authors: Luisa De Andrade Salles, Gilsane Lino Von Poser, Andréa Loviane Silva, Arthur Germano Fett-neto, Sandra Beatriz RechAbstract:A practical method for the multiplication of Valeriana glechomifolia Meyer was developed and valepotriates synthesis in the plantlets was studied. Axillary buds and shoot tips were cultured in 0.3/ Murashige and Skoog basal medium supplemented with either 0.4 mg l 1 of BAP or without plant growth regulators. The cultured segments grew on both media and produced roots after 3/4 weeks. The dienic valepotriates Valtrate, DIA-Valtrate, aceValtrate and 1-b-aceValtrate and the monoenic valepotriate didroValtrate have each been quantitated in the leaves, stems and roots of the micropropagated plantlets and compared with the field-grown plants by reversed-phase HPLC. Plantlets grown on growth regulator-free medium displayed higher valepotriate contents (ranging from 3.54% in stems to 0.98% in leaves) than with the addition of BAP (from 1.22% in leaves to 0.36% in stems) and field-grown plants (from 0.89% in stems to 0.10% in inflorescences). In most cases, aceValtrate was the most abundant compound. # 2002 Elsevier Science Ireland Ltd. All rights reserved.
Hui Wang - One of the best experts on this subject based on the ideXlab platform.
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overall process of using a valerate dominant sludge hydrolysate to produce high quality polyhydroxyalkanoates pha in a mixed culture
Scientific Reports, 2017Co-Authors: Jiuxiao Hao, Xiujin Wang, Hui WangAbstract:The overall process of polyhydroxyalkanoates (PHA) production in a mixed culture fed by thermophilic fermented valerate-dominant sludge hydrolysate with high-level soluble organics (proteins and carbohydrates) and nutrients (nitrogen and phosphorus) was investigated in this study. The valerate-dominant hydrolysate was fed to enrich a PHA culture with an increasing concentration, and the enriched culture displayed a strong PHA-producing capacity under feast-famine conditions. Valerate in the feedstock was preferentially utilized over acetate and butyrate, and its uptake correlated with the production of 3-hydroxyvalerate (3HV) and 3-hydroxy-2-methylvalerate (3H2MV). The maximum PHA content (42.31%) was highest to date in a mixed culture with complex feedstock, and the PHA consisted of 3-hydroxybutyrate (3HB), 3HV, 3H2MV at 68.4, 23.7, 7.9 mmol C%. PHA production was inhibited when the nutrients exceeded a certain limit. Microbial analysis revealed that valerate-dominant feedstock caused Delftia (53%) to become the prevailing group over other PHA-producing bacteria. For long-term operation, 75% of the biomass at the end of feast phase was collected for PHA recovery, and the entire process exhibited a potential to produce 5 g PHA from 1 kg sludge. These findings indicate that the complex valerate-dominant sludge hydrolysate can be used to stably produce PHA containing high 3HV and 3H2MV.
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investigation of polyhydroxyalkanoates phas biosynthesis from mixed culture enriched by valerate dominant hydrolysate
Frontiers of Environmental Science & Engineering in China, 2017Co-Authors: Jiuxiao Hao, Xiujin Wang, Hui WangAbstract:The production of polyhydroxyalkanoates (PHAs) with a high fraction of 3-hydroxyvalerate (3HV) and 3-hydroxy-2-methylvalerate (3H2MV) from mixed culture enriched by valerate-dominant hydrolysate was evaluated in this study. After long-term enrichment, the culture showed strong ability to synthesize 3HV and 3H2MV, even with acetate-dominant substrate. The ultilization of single or mixed iso-/n-valerate by the enriched culture showed that the mixture of iso-valerate and n-valerate was more efficient substrate than any single in terms of balancing microbial growth and PHAs synthesis. Besides, through comparing the kinetics and stoichiometry of the tests supplying valerate and propionate, the enriched culture with equivalent valerate and propionate (1:1 molar ratio) exhibited superior PHAs production performances to pure valerate or propionate, attaining more than 70 mol% of 3HVand 3H2MV. The above findings reveal that valerate-dominant hydrolysate is a kind of suitable substrate to enrich PHAs producing culture with great capability to synthesize 3HV and 3H2MV monomers, thus improving product properties than pure poly(3-hydroxybutyrate) (P3HB); also 3HV and 3H2MV production behaviors can be regulated by the type of odd-carbon VFAs in the substrate.
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valeriana jatamansi constituent ivhd Valtrate as a novel therapeutic agent to human ovarian cancer in vitro and in vivo activities and mechanisms
Current Cancer Drug Targets, 2013Co-Authors: Tao Chen, Sheng Lin, Jing Zhao, Peizhan Chen, He Guo, Yanling Liu, Ruiai Chu, Lei Shan, Weidong Zhang, Hui WangAbstract:Identification of novel chemotherapeutic agents from traditional medicines and elucidation of the molecular basis of their anticancer effects are critical and urgently needed for modern pharmacotherapy. We previously found that analogs of the compounds present in Valeriana jatamansi, a traditional medicine used to treat mental disorders, possess notable antitumor properties; however, the underlying molecular mechanisms have not been fully demonstrated. In this study, we evaluated the anticancer effects of IVHD-Valtrate, one of the most active Valeriana jatamansi derivatives, against human ovarian cancer cells in vitro and in vivo. IVHD-Valtrate inhibited the growth and proliferation of the A2780 and OVCAR-3 ovarian cancer cell lines in a concentration-dependent manner, while relatively low cytotoxicity to immortalized non-tumorigenic human ovarian surface epithelial cells (IOSE-144) was observed. Treatment with IVHDValtrate arrested the ovarian cancer cells in the G2/M phase and induced apoptosis, and significantly suppressed the growth of A2780 and OVCAR3 xenograft tumors in a dose-dependent manner. The detailed in vitro and in vivo study on the molecular mechanisms of this compound demonstrated that IVHD-Valtrate exposure modulated the expression of numerous molecules involved in cell cycle progression and apoptosis regardless of p53 status, leading to increase the level of p53, Rb, p21, p27 and decrease Mdm2, E2F1, Cyclin B1, Cdc25C and Cdc2. It also down-regulated Bcl-2/Bax and Bcl-2/Bad ratio and enhanced the cleavage of PARP and Caspases. Our preclinical results indicated IVHD-Valtrate is a potential therapeutic agent for ovarian cancer, providing a basis for development of the compound as a novel chemotherapeutic agent.
