The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Marc-andré Fliniaux - One of the best experts on this subject based on the ideXlab platform.
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immobilization of nicotiana tabacum plant cell suspensions within calcium alginate gel beads for the production of enhanced amounts of Scopolin
Enzyme and Microbial Technology, 2000Co-Authors: F Gilleta, Marc-andré Fliniaux, C Roisin, Jacquin A Dubreuil, Jeannoel Barbotin, J Nava E SaucedoAbstract:Scopolin-producing cells of Nicotiana tabacum were immobilized within Ca-alginate gel beads. Free cell suspensions accumulated Scopolin within cytoplasmic compartments and cell disruption was necessary to recover Scopolin. On the contrary, immobilized plant cells excreted considerable amounts of Scopolin. Scopolin diffused throughout the gel matrix and reached the culture media. A large fraction of produced Scopolin could then be recovered from the culture medium without disrupting cells. Immobilized N. tabacum cells produced more Scopolin than free cell suspensions did (3.8 mg/g fresh weight biomass [into the culture media] versus 0.2 mg/g fresh weight biomass [intracellular]). Variation of the immobilization conditions revealed a marked influence on the behavior of N. tabacum plant cells: production of Scopolin and enhanced excretion, cell growth, and morphological aspect of plant cell colonies. This excretion phenomenon could be used advantageously at an industrial production level.
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Evaluation of the relation between the endogenous scopoletin and Scopolin level of some solanaceous and papaver cell suspensions and their ability to bioconvert scopoletin to Scopolin
Plant Science, 1997Co-Authors: Marc-andré Fliniaux, Françoise Gillet-manceau, Danielle Marty, Jean-pierre Monti, Thomas Macek, Annie Jacquin-dubreuilAbstract:Abstract Endogenous Scopolin and its aglycon scopoletin were tested in various plant cell suspensions by HPLC. The results indicate that the levels of these compounds varied greatly from one plant cell suspension to another (10 −3 –5 mg/g dry mass). Both scopoletin and Scopolin were detected in the Nicotiana tabacum L. cell suspensions while only Scopolin was detected in the Duboisia myoporoides R.Br., Solanum aviculare Forst. and Papaver somniferum L. cells. The identity of this Scopolin was confirmed by NMR and MS data. Neither of these compounds was accumulated in the Nicotiana plumbaginifolia Viv. cell suspensions. Moreover, all the cell suspensions, except N. tabacum could bioconvert exogenous scopoletin to Scopolin. The yield of the bioconversion varied from one cell suspension to another (21–92%). No correlation could be established between the capacity of the cells to bioconvert scopoletin to Scopolin and the endogenous Scopolin level.
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enhanced production of Scopolin bysolanum aviculare cells immobilised within ca alginate gel beads
Plant Cell Reports, 1997Co-Authors: C Roisin, Marc-andré Fliniaux, J Nava E Saucedo, Francois Gilletmanceau, Annie Jacquindubreuil, J N BarbotinAbstract:Different matrices, obtained by varying calcium (0.1 to 1.5M) and alginate (1 to 1.5%) concentrations, were used to study the influence of immobilisation parameters on the behaviour ofS. aviculare. A significant modulation of cell growth, cell release, and Scopolin production and excretion has been observed. Physiological and morphological characteristics ofSolanum aviculare cells immobilised within Ca-alginate beads were notably different from those of suspended cells. ImmobilisedS. aviculare have accumulated Scopolin (up to 120 μg·g-1 FWB) within beads and excreted it into the culture medium (up to 8 μg·g-1 FWB). Contrary to suspended cells which have accumulated only traces of this metabolite within intracellular compartments (1 μg·g-1 FWB), no Scopolin has been found into the culture medium.
Yufeng Xia - One of the best experts on this subject based on the ideXlab platform.
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Scopolin isolated from erycibe obtusifolia benth stems suppresses adjuvant induced rat arthritis by inhibiting inflammation and angiogenesis
International Immunopharmacology, 2009Co-Authors: Rong Pan, Yue Dai, Xinghua Gao, Yufeng XiaAbstract:Despite Scopolin is a main coumarin constituent in the stems of Erycibe obtusifolia Benth, a herb drug that has long been utilized in traditional Chinese medicine for the treatment of rheumatoid arthritis, little information is available about the pharmacological activities of this compound. The present study was performed to investigate the anti-rheumatic effects of Scopolin in adjuvant-induced arthritis (AIA) in rats, and explore the underlying mechanisms of action in views of anti-inflammatory and anti-angiogenic properties in the synovial tissues. Scopolin (50, 100 mg/kg), injected intraperitoneally for 10 days from the onset of secondary response, significantly inhibited both inoculated and non-inoculated paw swelling as well as articular index scores in AIA. Meanwhile, the mean body weight of rats treated with Scopolin was higher than that of model group. Rats treated with high dose of Scopolin (100 mg/kg) preserved a nearly normal histological architecture of the joints and showed a significant reduction of the new blood vessels in the synovial tissues. Additionally, Scopolin could reduce IL-6, VEGF and FGF-2 expressions in rat synovial tissues. In conclusion, Scopolin can reduce the clinical symptoms of rat AIA by inhibiting inflammation and angiogenesis, and this compound may be a potent agent for angiogenesis related diseases and can serve as a structural base for screening more potent synthetic analogs.
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a high performance liquid chromatographic method for determination of Scopolin in rat plasma application to pharmacokinetic studies
Biomedical Chromatography, 2008Co-Authors: Yufeng Xia, Yue Dai, Qiang Wang, Fei CaiAbstract:An analytical method based on high-performance liquid chromatographic (HPLC) with ultraviolet (UV) detection was developed for determination of Scopolin in rat plasma using aesculin as internal standard (IS). After protein precipitation of plasma sample with methanol, the supernatant was directly injected and analyzed. Chromatographic separation was achieved on a C18 column using methanol and distilled water (22:78, v/v) containing 0.2% (v/v) glacial acetic acid as mobile phase with a column temperature of 30 degrees C. The UV detector was set at 338 nm. The calibration curve was linear over the range of 0.105-13.125 microg/mL with a correlation coefficient of 0.9998. The retention times of aesculin and Scopolin were 10.4 and 12.8 min, respectively. The recoveries for plasma samples of 0.105, 4.725 and 13.125 microg/mL were 91.08, 95.30 and 96.10%, respectively. The RSD of intra- and inter-day assay variations was less than 7.35%. The lower limit of detection was 0.03 microg/mL .This HPLC assay is a simple, sensitive and accurate and was successfully applied to the pharmacokinetic study of Scopolin in rats.
Mitsuo Okazaki - One of the best experts on this subject based on the ideXlab platform.
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scopoletin uptake from culture medium and accumulation in the vacuoles after conversion to Scopolin in 2 4 d treated tobacco cells
Plant Science, 2000Co-Authors: Goro Taguchi, Shinobu Fujikawa, Teruyoshi Yazawa, Ritsuko Kodaira, Nobuaki Hayashida, Makoto Shimosaka, Mitsuo OkazakiAbstract:Abstract Tobacco ( Nicotiana tabacum L. Bright Yellow) T-13 cell line has the ability to produce scopoletin endogenously and release some of it into the culture medium. We investigated the mechanism of scopoletin uptake following treatment of a tobacco culture with 2,4-dichlorophenoxyacetic acid (2,4-D). Addition of [ 14 C]-labeled scopoletin showed that scopoletin was taken up by 2,4-D-treated cells and converted to Scopolin, a 7- O -glucoside of scopoletin. This uptake of scopoletin began 6 h after 2,4-D addition to the cells. Experiments using several inhibitors showed that this uptake was energy-dependent. The phenomenon of 2,4-D-stimulated uptake was observed only for 7-hydroxycoumarins, such as scopoletin, umbelliferone and esculetin. To further investigate the site for scopoletin accumulation, we separated the vacuoles from T-13 cells and quantified the coumarin contents in this fraction. Most of the scopoletin in the vacuoles was present as glucoconjugate, Scopolin. Moreover, glucosylation activity was absent from isolated vacuoles and, therefore, is likely to be located in the cytosol. Therefore, we can state that 2,4-D treatment of tobacco cells stimulated scopoletin uptake. The scopoletin was converted into Scopolin in the cytoplasm, and then transferred into the vacuoles.
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effects of methyl jasmonate and elicitor on the activation of phenylalanine ammonia lyase and the accumulation of scopoletin and Scopolin in tobacco cell cultures
Plant Science, 1998Co-Authors: Manisha Sharan, Goro Taguchi, Nobuaki Hayashida, Keiichi Gonda, Takashi Jouke, Makoto Shimosaka, Mitsuo OkazakiAbstract:Abstract The effects of methyl jasmonate (MJ) and elicitor on the phenylpropanoid metabolism in tobacco was studied. It was found that suspended cells of tobacco, responded to MJ and elicitor from the plant pathogenic fungus Fusarium solani with differential formation of phenolic compounds. Both MJ and elicitor induced phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) activity to comparable levels. Northern hybridization showed that the increase in PAL activity was preceded by PAL mRNA accumulation. PAL was induced transcriptionally and enzymatically faster in elicitor-treated cells as compared to MJ-treated cells. HPLC of extracts from tobacco cells and their culture filtrate treated with MJ, showed an induction of the syntheses of coumarin-scopoletin and Scopolin. This effect was not seen in elicitor-treated or control cell cultures. Scopolin was mainly found within the cell (99%), whereas scopoletin accumulated in the culture filtrate (90%). We conclude that though MJ mimics stress, indicating its possible role in the plant defense metabolism, responses of tobacco cells to MJ and elicitor are distinct.
J Nava E Saucedo - One of the best experts on this subject based on the ideXlab platform.
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immobilization of nicotiana tabacum plant cell suspensions within calcium alginate gel beads for the production of enhanced amounts of Scopolin
Enzyme and Microbial Technology, 2000Co-Authors: F Gilleta, Marc-andré Fliniaux, C Roisin, Jacquin A Dubreuil, Jeannoel Barbotin, J Nava E SaucedoAbstract:Scopolin-producing cells of Nicotiana tabacum were immobilized within Ca-alginate gel beads. Free cell suspensions accumulated Scopolin within cytoplasmic compartments and cell disruption was necessary to recover Scopolin. On the contrary, immobilized plant cells excreted considerable amounts of Scopolin. Scopolin diffused throughout the gel matrix and reached the culture media. A large fraction of produced Scopolin could then be recovered from the culture medium without disrupting cells. Immobilized N. tabacum cells produced more Scopolin than free cell suspensions did (3.8 mg/g fresh weight biomass [into the culture media] versus 0.2 mg/g fresh weight biomass [intracellular]). Variation of the immobilization conditions revealed a marked influence on the behavior of N. tabacum plant cells: production of Scopolin and enhanced excretion, cell growth, and morphological aspect of plant cell colonies. This excretion phenomenon could be used advantageously at an industrial production level.
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enhanced production of Scopolin bysolanum aviculare cells immobilised within ca alginate gel beads
Plant Cell Reports, 1997Co-Authors: C Roisin, Marc-andré Fliniaux, J Nava E Saucedo, Francois Gilletmanceau, Annie Jacquindubreuil, J N BarbotinAbstract:Different matrices, obtained by varying calcium (0.1 to 1.5M) and alginate (1 to 1.5%) concentrations, were used to study the influence of immobilisation parameters on the behaviour ofS. aviculare. A significant modulation of cell growth, cell release, and Scopolin production and excretion has been observed. Physiological and morphological characteristics ofSolanum aviculare cells immobilised within Ca-alginate beads were notably different from those of suspended cells. ImmobilisedS. aviculare have accumulated Scopolin (up to 120 μg·g-1 FWB) within beads and excreted it into the culture medium (up to 8 μg·g-1 FWB). Contrary to suspended cells which have accumulated only traces of this metabolite within intracellular compartments (1 μg·g-1 FWB), no Scopolin has been found into the culture medium.
Yue Dai - One of the best experts on this subject based on the ideXlab platform.
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Scopolin isolated from erycibe obtusifolia benth stems suppresses adjuvant induced rat arthritis by inhibiting inflammation and angiogenesis
International Immunopharmacology, 2009Co-Authors: Rong Pan, Yue Dai, Xinghua Gao, Yufeng XiaAbstract:Despite Scopolin is a main coumarin constituent in the stems of Erycibe obtusifolia Benth, a herb drug that has long been utilized in traditional Chinese medicine for the treatment of rheumatoid arthritis, little information is available about the pharmacological activities of this compound. The present study was performed to investigate the anti-rheumatic effects of Scopolin in adjuvant-induced arthritis (AIA) in rats, and explore the underlying mechanisms of action in views of anti-inflammatory and anti-angiogenic properties in the synovial tissues. Scopolin (50, 100 mg/kg), injected intraperitoneally for 10 days from the onset of secondary response, significantly inhibited both inoculated and non-inoculated paw swelling as well as articular index scores in AIA. Meanwhile, the mean body weight of rats treated with Scopolin was higher than that of model group. Rats treated with high dose of Scopolin (100 mg/kg) preserved a nearly normal histological architecture of the joints and showed a significant reduction of the new blood vessels in the synovial tissues. Additionally, Scopolin could reduce IL-6, VEGF and FGF-2 expressions in rat synovial tissues. In conclusion, Scopolin can reduce the clinical symptoms of rat AIA by inhibiting inflammation and angiogenesis, and this compound may be a potent agent for angiogenesis related diseases and can serve as a structural base for screening more potent synthetic analogs.
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a high performance liquid chromatographic method for determination of Scopolin in rat plasma application to pharmacokinetic studies
Biomedical Chromatography, 2008Co-Authors: Yufeng Xia, Yue Dai, Qiang Wang, Fei CaiAbstract:An analytical method based on high-performance liquid chromatographic (HPLC) with ultraviolet (UV) detection was developed for determination of Scopolin in rat plasma using aesculin as internal standard (IS). After protein precipitation of plasma sample with methanol, the supernatant was directly injected and analyzed. Chromatographic separation was achieved on a C18 column using methanol and distilled water (22:78, v/v) containing 0.2% (v/v) glacial acetic acid as mobile phase with a column temperature of 30 degrees C. The UV detector was set at 338 nm. The calibration curve was linear over the range of 0.105-13.125 microg/mL with a correlation coefficient of 0.9998. The retention times of aesculin and Scopolin were 10.4 and 12.8 min, respectively. The recoveries for plasma samples of 0.105, 4.725 and 13.125 microg/mL were 91.08, 95.30 and 96.10%, respectively. The RSD of intra- and inter-day assay variations was less than 7.35%. The lower limit of detection was 0.03 microg/mL .This HPLC assay is a simple, sensitive and accurate and was successfully applied to the pharmacokinetic study of Scopolin in rats.