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Michel Frederich - One of the best experts on this subject based on the ideXlab platform.
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dimeric bisindole alkaloids from the stem bark of strychnos Nux Vomica l
Phytochemistry, 2013Co-Authors: Mariecaroline Jonville, Joanne Bero, Monique Tits, Luc Angenot, Georges Dive, Evelyne Ollivier, Michel FrederichAbstract:Strychnos Nux-Vomica L. (Loganiaceae) is famous for its monomeric alkaloid content, such as strychnine, a convulsant poison. The stem bark of the tree is traditionally used to treat intermittent fever in South East Asia. In various studies, it appeared that dimeric indolo-monoterpenic alkaloids possess a promising activity on Plasmodium falciparum. Three bisindolomonoterpenic alkaloids together with strychnochrysine, previously identified in the root bark of S. Nux-Vomica, were isolated from the stem bark. The structures of these compounds were established using NMR spectroscopy and mass spectrometry. Stereochemistry of the compounds was confirmed by molecular modelling. This then allowed the structural determination of strychnoflavine, a coloured bisindole alkaloid previously isolated from the root bark of the tree. Moreover, the conformational inversion in alkaloids possessing an ether bond in the strychnane moiety could be easily predicted by specific δ 13 C NMR values. These longicaudatine-type alkaloids were found to display in vitro antiplasmodial activity against a chloroquine resistant strain and a chloroquine sensitive strain. The most interesting was strychnochrysine showing an IC 50 value at around 10 μM. © 2012 Elsevier Ltd. All rights reserved.
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metabolomic analysis of strychnos Nux Vomica strychnos icaja and strychnos ignatii extracts by 1h nuclear magnetic resonance spectrometry and multivariate analysis techniques
Phytochemistry, 2004Co-Authors: Alfons W.m. Lefeber, Goetz Harnischfeger, Michel Frederich, Luc Angenot, Young Hae Choi, Robert VerpoorteAbstract:Abstract 1 H Nuclear magnetic resonance spectrometry and multivariate analysis techniques were applied for the metabolic profiling of three Strychnos species: Strychnos Nux-Vomica (seeds, stem bark, root bark), Strychnos ignatii (seeds), and Strychnos icaja (leaves, stem bark, root bark, collar bark). The principal component analysis (PCA) of the 1 H NMR spectra showed a clear discrimination between all samples, using the three first components. The key compounds responsible for the discrimination were brucine, loganin, fatty acids, and Strychnos icaja alkaloids such as icajine and sungucine. The method was then applied to the classification of several “false angostura” samples. These samples were, as expected, identified as S. Nux-Vomica by PCA, but could not be clearly discriminated as root bark or stem bark samples after further statistical analysis.
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quantitative analysis of strychnine and brucine in strychnos Nux Vomica using 1h nmr
Planta Medica, 2003Co-Authors: Michel Frederich, Young Hae Choi, Robert VerpoorteAbstract:A quantitative analysis using 1 H-NMR (Q-NMR) has been developed for the determination of strychnine and brucine in Strychnos Nux-Vomica seeds and stems. The advantages of the method are that no reference alkaloids are needed for calibration curves, the quantification could be directly realized on a crude extract, strychnine and brucine could easily be distinguished, an overall profile of the preparation (including non alkaloid compounds) could be directly obtained, and a very significant time-gain could be achieved, in comparison to conventional HPLC methods, for instance.
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strychnochrysine a new bisindole alkaloid from the roots of strychnos Nux Vomica
Journal of Natural Products, 1998Co-Authors: Rose Gadi Biala, Viviane Brandt, Christelle Prosperi, Monique Tits, Gabriel Llabres, Michel Frederich, Jacques Penelle, Luc AngenotAbstract:The reinvestigation of Strychnos Nux-Vomica resulted in the isolation of a colored monoquaternary bisindole alkaloid from the roots. The structure of this new orange substance, strychnochrysine (1), was defined by detailed spectroscopic methods.
Luc Angenot - One of the best experts on this subject based on the ideXlab platform.
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dimeric bisindole alkaloids from the stem bark of strychnos Nux Vomica l
Phytochemistry, 2013Co-Authors: Mariecaroline Jonville, Joanne Bero, Monique Tits, Luc Angenot, Georges Dive, Evelyne Ollivier, Michel FrederichAbstract:Strychnos Nux-Vomica L. (Loganiaceae) is famous for its monomeric alkaloid content, such as strychnine, a convulsant poison. The stem bark of the tree is traditionally used to treat intermittent fever in South East Asia. In various studies, it appeared that dimeric indolo-monoterpenic alkaloids possess a promising activity on Plasmodium falciparum. Three bisindolomonoterpenic alkaloids together with strychnochrysine, previously identified in the root bark of S. Nux-Vomica, were isolated from the stem bark. The structures of these compounds were established using NMR spectroscopy and mass spectrometry. Stereochemistry of the compounds was confirmed by molecular modelling. This then allowed the structural determination of strychnoflavine, a coloured bisindole alkaloid previously isolated from the root bark of the tree. Moreover, the conformational inversion in alkaloids possessing an ether bond in the strychnane moiety could be easily predicted by specific δ 13 C NMR values. These longicaudatine-type alkaloids were found to display in vitro antiplasmodial activity against a chloroquine resistant strain and a chloroquine sensitive strain. The most interesting was strychnochrysine showing an IC 50 value at around 10 μM. © 2012 Elsevier Ltd. All rights reserved.
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metabolomic analysis of strychnos Nux Vomica strychnos icaja and strychnos ignatii extracts by 1h nuclear magnetic resonance spectrometry and multivariate analysis techniques
Phytochemistry, 2004Co-Authors: Alfons W.m. Lefeber, Goetz Harnischfeger, Michel Frederich, Luc Angenot, Young Hae Choi, Robert VerpoorteAbstract:Abstract 1 H Nuclear magnetic resonance spectrometry and multivariate analysis techniques were applied for the metabolic profiling of three Strychnos species: Strychnos Nux-Vomica (seeds, stem bark, root bark), Strychnos ignatii (seeds), and Strychnos icaja (leaves, stem bark, root bark, collar bark). The principal component analysis (PCA) of the 1 H NMR spectra showed a clear discrimination between all samples, using the three first components. The key compounds responsible for the discrimination were brucine, loganin, fatty acids, and Strychnos icaja alkaloids such as icajine and sungucine. The method was then applied to the classification of several “false angostura” samples. These samples were, as expected, identified as S. Nux-Vomica by PCA, but could not be clearly discriminated as root bark or stem bark samples after further statistical analysis.
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strychnochrysine a new bisindole alkaloid from the roots of strychnos Nux Vomica
Journal of Natural Products, 1998Co-Authors: Rose Gadi Biala, Viviane Brandt, Christelle Prosperi, Monique Tits, Gabriel Llabres, Michel Frederich, Jacques Penelle, Luc AngenotAbstract:The reinvestigation of Strychnos Nux-Vomica resulted in the isolation of a colored monoquaternary bisindole alkaloid from the roots. The structure of this new orange substance, strychnochrysine (1), was defined by detailed spectroscopic methods.
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a new hplc method for the assay of alkaloids in strychnos Nux Vomica and strychnos ignatii
Fitoterapia, 1996Co-Authors: Rose Gadi Biala, Monique Tits, Jeannoel Wauters, Luc AngenotAbstract:A reversed-phase high-performance liquid chromatographic procedure was developed for the qualitative and quantitative analysis of the alkaloids in S. Nux-Vomica and S. ignatii.
Robert Verpoorte - One of the best experts on this subject based on the ideXlab platform.
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metabolomic analysis of strychnos Nux Vomica strychnos icaja and strychnos ignatii extracts by 1h nuclear magnetic resonance spectrometry and multivariate analysis techniques
Phytochemistry, 2004Co-Authors: Alfons W.m. Lefeber, Goetz Harnischfeger, Michel Frederich, Luc Angenot, Young Hae Choi, Robert VerpoorteAbstract:Abstract 1 H Nuclear magnetic resonance spectrometry and multivariate analysis techniques were applied for the metabolic profiling of three Strychnos species: Strychnos Nux-Vomica (seeds, stem bark, root bark), Strychnos ignatii (seeds), and Strychnos icaja (leaves, stem bark, root bark, collar bark). The principal component analysis (PCA) of the 1 H NMR spectra showed a clear discrimination between all samples, using the three first components. The key compounds responsible for the discrimination were brucine, loganin, fatty acids, and Strychnos icaja alkaloids such as icajine and sungucine. The method was then applied to the classification of several “false angostura” samples. These samples were, as expected, identified as S. Nux-Vomica by PCA, but could not be clearly discriminated as root bark or stem bark samples after further statistical analysis.
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quantitative analysis of strychnine and brucine in strychnos Nux Vomica using 1h nmr
Planta Medica, 2003Co-Authors: Michel Frederich, Young Hae Choi, Robert VerpoorteAbstract:A quantitative analysis using 1 H-NMR (Q-NMR) has been developed for the determination of strychnine and brucine in Strychnos Nux-Vomica seeds and stems. The advantages of the method are that no reference alkaloids are needed for calibration curves, the quantification could be directly realized on a crude extract, strychnine and brucine could easily be distinguished, an overall profile of the preparation (including non alkaloid compounds) could be directly obtained, and a very significant time-gain could be achieved, in comparison to conventional HPLC methods, for instance.
Young Hae Choi - One of the best experts on this subject based on the ideXlab platform.
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analysis of strychnine from detoxified strychno Nux Vomica seeds using liquid chromatography electrospray mass spectrometry
Journal of Ethnopharmacology, 2004Co-Authors: Young Hae Choi, You-min Sohn, Chul Young Kim, Jinwoong KimAbstract:The content of strychnine from Strychnos Nux-Vomica [corrected] seeds was analyzed and compared to processed seeds by the HPLC-ESI/MS method. Using this technique, levels as low as 1 ng of strychnine were detected. In contrast to conventional UV detectors, this method also made it possible to discriminate brucine. This study resulted in finding the content of strychnine in detoxified seeds to be one tenth of unprocessed Strychnos Nux-Vomica [corrected] seeds.
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metabolomic analysis of strychnos Nux Vomica strychnos icaja and strychnos ignatii extracts by 1h nuclear magnetic resonance spectrometry and multivariate analysis techniques
Phytochemistry, 2004Co-Authors: Alfons W.m. Lefeber, Goetz Harnischfeger, Michel Frederich, Luc Angenot, Young Hae Choi, Robert VerpoorteAbstract:Abstract 1 H Nuclear magnetic resonance spectrometry and multivariate analysis techniques were applied for the metabolic profiling of three Strychnos species: Strychnos Nux-Vomica (seeds, stem bark, root bark), Strychnos ignatii (seeds), and Strychnos icaja (leaves, stem bark, root bark, collar bark). The principal component analysis (PCA) of the 1 H NMR spectra showed a clear discrimination between all samples, using the three first components. The key compounds responsible for the discrimination were brucine, loganin, fatty acids, and Strychnos icaja alkaloids such as icajine and sungucine. The method was then applied to the classification of several “false angostura” samples. These samples were, as expected, identified as S. Nux-Vomica by PCA, but could not be clearly discriminated as root bark or stem bark samples after further statistical analysis.
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quantitative analysis of strychnine and brucine in strychnos Nux Vomica using 1h nmr
Planta Medica, 2003Co-Authors: Michel Frederich, Young Hae Choi, Robert VerpoorteAbstract:A quantitative analysis using 1 H-NMR (Q-NMR) has been developed for the determination of strychnine and brucine in Strychnos Nux-Vomica seeds and stems. The advantages of the method are that no reference alkaloids are needed for calibration curves, the quantification could be directly realized on a crude extract, strychnine and brucine could easily be distinguished, an overall profile of the preparation (including non alkaloid compounds) could be directly obtained, and a very significant time-gain could be achieved, in comparison to conventional HPLC methods, for instance.
Majeti Narsimha Vara Prasad - One of the best experts on this subject based on the ideXlab platform.
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strychnos Nux Vomica root extract induces apoptosis in the human multiple myeloma cell line u266b1
Cell Biochemistry and Biophysics, 2013Co-Authors: Majeti Narsimha Vara PrasadAbstract:Multiple myeloma (MM) is an incurable B cell neoplasm causing significant morbidity and mortality. Despite recent advances in the MM-treatment, the disease still remains incurable; necessitating a search for new therapeutic agents. Therefore, Strychnos Nux-Vomica L. root extract (SN) was screened using the human MM-cell line, U266B1. SN-extract demonstrated anti-proliferative effect in a time- and dose-dependent manner. Morphological studies, cell cycle analysis by FACS indicate apoptosis. Furthermore, assessment of signaling molecules like IL-6 (interleukin-6) and CD-138 (Sydencan-1) confirmed apoptosis. The anti-proliferative activity of SN-extract is associated with apoptosis, which is likely due to the presence of alkaloids, strychnine and brucine, which have been identified by MALDI-TOF-MS and RP-HPLC analysis
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anti proliferative and cytotoxic effects of strychnos Nux Vomica root extract on human multiple myeloma cell line rpmi 8226
Food and Chemical Toxicology, 2009Co-Authors: Madduri Ramanadham, Majeti Narsimha Vara PrasadAbstract:Multiple myeloma (MM) is an incurable hematological malignancy with high incidence in the elderly. The currently used chemotherapeutic drugs show severe side effects, dose-limiting toxicity and development of resistance. In search of novel plant derived anti-cancer agents, Strychnos Nux-Vomica L. (SN) root extract was screened using the human MM-cell line, RPMI 8226. SN-extract exhibited anti-proliferative activity in a dose and time dependent manner. The morphological assessment of SN-extract treated cells showed significant features associated with apoptosis. Cell cycle analysis using flow cytometry of cells stained with propidium iodide revealed accumulation of cells at sub-G0/G1 phase. In addition, disruption of mitochondrial membrane potential and subsequent leakage of mitochondrial cytochrome c was observed in SN-extract treated myeloma cells. The anti-proliferative and cytotoxic activity could be due to the alkaloids strychnine and brucine, which have been identified by LC–mass spectral analysis of the SN-extract in comparison to the reference standards analyzed under identical conditions.