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Robert Verpoorte - One of the best experts on this subject based on the ideXlab platform.
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antiplasmodial activity of sesquiterpene lactones and a sucrose ester from Vernonia guineensis benth asteraceae
Journal of Ethnopharmacology, 2013Co-Authors: Ngeh J Toyang, Pierre Tane, Joseph Bryant, Michael Krause, Rick M Fairhurst, Robert VerpoorteAbstract:Ethnopharmacological relevance Aqueous preparations of Vernonia guineensis Benth. (Asteraceae) are used in Cameroonian folk medicine as a general stimulant and to treat various illnesses and conditions including malaria, bacterial infections and helminthic infestations.
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a review of the medicinal potentials of plants of the genus Vernonia asteraceae
Journal of Ethnopharmacology, 2013Co-Authors: Ngeh J Toyang, Robert VerpoorteAbstract:Abstract Ethnopharmacological relevance The Vernonia genus has about one thousand species and members of the genus are widely used as food and medicine. The aim of this review is to analyze published data on the ethnomedicinal, ethnoveterinary and zoopharmacognostic uses of plants of the Vernonia genus. This will help to identify the state of ethnopharmacological knowledge in regard to this genus and to propose future research priorities. Materials and methods The major scientific databases including SciFinder, Sciencedirect, Medline and Google Scholar were queried for information on Vernonia genus using various keyword combinations. The International Plant Name Index was also used to verify the names of species and authors. Results A total of 109 Vernonia species were reported in the literature to have medicinal properties. One hundred and five (105) plants were linked to the treatment or management of 44 human diseases or health conditions. Plants of the genus also feature in ethnoveterinary and zoopharmacognostic practices. A total of 12 Vernonia species were identified to be used in ethnoveterinary medicine while 2 species are used in self medication practices by chimpanzees and gorillas. In vitro and in vivo research studies reporting the validation of the medicinal properties of some species were also reviewed. One hundred and three bioactive compounds isolated from various Vernonia species were also identified. Vernonia amygdalina was identified as the most frequently used member of the Vernonia genus. The Vernolides, a class of sesquiterpene lactone were identified as the most studied compounds from the genus and show interesting bioactivity in antiplasmodial, antileishmanial, antischistosomial, cytotoxicity, antimicrobial and anti-inflammatory assays. Conclusion On the basis of results from a combination of in vitro and in vivo efficacy and toxicity studies reported, Vernonia amygdalina holds the most promise for development into a nutraceutical against diabetes and malaria while Vernonia cinerea has potential against cancer and inflammatory conditions. Vernolide A is so far the most promising single agent from a Vernonia species that has potential for development into an anticancer agent. The other Vernonia species and isolated compounds require further studies to ascertain their medicinal potentials.
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cytotoxic sesquiterpene lactones from the leaves of Vernonia guineensis benth asteraceae
Journal of Ethnopharmacology, 2013Co-Authors: Ngeh J Toyang, Hippolyte K Wabo, Eugene N Ateh, Harry Davis, Pierre Tane, Luc B Sondengam, Joseph Bryant, Robert VerpoorteAbstract:Abstract Ethnopharmacological relevance Vernonia guineensis Benth. (Asteraceae) preparations are used in folk medicine in Cameroon to treat a number of ailments, including prostate cancer and malaria, and is used as an anthelmintic, adaptogen and antidote. The aim of this study was to continue the validation of the activity of Vernonia guineensis Benth. extracts and isolated molecules against cancer cell lines following the previous isolation of an anti-prostate cancer sugar ester from the root extract. Materials and methods Acetone extracts of Vernonia guineensis Benth. leaves were tested for activity against 10 cancer cell lines (Breast—MDA-MB-231, Breast—MCF-7, Colon—HCT-116, Leukemia—HL-60, Lung—A549, Melanoma—A375, Ovarian—OVCAR3, Pancreas—Mia-paca, Prostate—PC-3 and Prostate—DU-145). The acetone extract was subjected to bioactivity guided fractionation. Anti-proliferation and clonogenic activity of the isolated compounds were tested. The WST-1 assay was used for the anti-proliferation activity, while the standard clonogenic test was used to determine the clonogenic activity. Results The acetone extract of Vernonia guineensis Benth. demonstrated in vitro activity ranging from IC50 4–26 μg/mL against the 10 cell lines. Activity guided fractionation of this extract yielded two sesquiterpene lactones, isolated for the first time from the genus Vernonia. The compounds were characterized using spectroscopic experiments, including a combination of 1D and 2D NMR data. Vernopicrin (1) and Vernomelitensin (2) demonstrated in vitro activity against human cancer cell lines with IC50 ranging from 0.35–2.04 μM (P Conclusion The cytotoxicity demonstrated by the crude extract and isolated sesquiterpenes against cancer cell lines highlights the medicinal potential of V. guineensis. The selective anti-proliferation and dose dependent anticlonogenic activities suggest that the identified sesquiterpenes could be potential antitumor agents.
Ngeh J Toyang - One of the best experts on this subject based on the ideXlab platform.
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antiplasmodial activity of sesquiterpene lactones and a sucrose ester from Vernonia guineensis benth asteraceae
Journal of Ethnopharmacology, 2013Co-Authors: Ngeh J Toyang, Pierre Tane, Joseph Bryant, Michael Krause, Rick M Fairhurst, Robert VerpoorteAbstract:Ethnopharmacological relevance Aqueous preparations of Vernonia guineensis Benth. (Asteraceae) are used in Cameroonian folk medicine as a general stimulant and to treat various illnesses and conditions including malaria, bacterial infections and helminthic infestations.
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a review of the medicinal potentials of plants of the genus Vernonia asteraceae
Journal of Ethnopharmacology, 2013Co-Authors: Ngeh J Toyang, Robert VerpoorteAbstract:Abstract Ethnopharmacological relevance The Vernonia genus has about one thousand species and members of the genus are widely used as food and medicine. The aim of this review is to analyze published data on the ethnomedicinal, ethnoveterinary and zoopharmacognostic uses of plants of the Vernonia genus. This will help to identify the state of ethnopharmacological knowledge in regard to this genus and to propose future research priorities. Materials and methods The major scientific databases including SciFinder, Sciencedirect, Medline and Google Scholar were queried for information on Vernonia genus using various keyword combinations. The International Plant Name Index was also used to verify the names of species and authors. Results A total of 109 Vernonia species were reported in the literature to have medicinal properties. One hundred and five (105) plants were linked to the treatment or management of 44 human diseases or health conditions. Plants of the genus also feature in ethnoveterinary and zoopharmacognostic practices. A total of 12 Vernonia species were identified to be used in ethnoveterinary medicine while 2 species are used in self medication practices by chimpanzees and gorillas. In vitro and in vivo research studies reporting the validation of the medicinal properties of some species were also reviewed. One hundred and three bioactive compounds isolated from various Vernonia species were also identified. Vernonia amygdalina was identified as the most frequently used member of the Vernonia genus. The Vernolides, a class of sesquiterpene lactone were identified as the most studied compounds from the genus and show interesting bioactivity in antiplasmodial, antileishmanial, antischistosomial, cytotoxicity, antimicrobial and anti-inflammatory assays. Conclusion On the basis of results from a combination of in vitro and in vivo efficacy and toxicity studies reported, Vernonia amygdalina holds the most promise for development into a nutraceutical against diabetes and malaria while Vernonia cinerea has potential against cancer and inflammatory conditions. Vernolide A is so far the most promising single agent from a Vernonia species that has potential for development into an anticancer agent. The other Vernonia species and isolated compounds require further studies to ascertain their medicinal potentials.
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cytotoxic sesquiterpene lactones from the leaves of Vernonia guineensis benth asteraceae
Journal of Ethnopharmacology, 2013Co-Authors: Ngeh J Toyang, Hippolyte K Wabo, Eugene N Ateh, Harry Davis, Pierre Tane, Luc B Sondengam, Joseph Bryant, Robert VerpoorteAbstract:Abstract Ethnopharmacological relevance Vernonia guineensis Benth. (Asteraceae) preparations are used in folk medicine in Cameroon to treat a number of ailments, including prostate cancer and malaria, and is used as an anthelmintic, adaptogen and antidote. The aim of this study was to continue the validation of the activity of Vernonia guineensis Benth. extracts and isolated molecules against cancer cell lines following the previous isolation of an anti-prostate cancer sugar ester from the root extract. Materials and methods Acetone extracts of Vernonia guineensis Benth. leaves were tested for activity against 10 cancer cell lines (Breast—MDA-MB-231, Breast—MCF-7, Colon—HCT-116, Leukemia—HL-60, Lung—A549, Melanoma—A375, Ovarian—OVCAR3, Pancreas—Mia-paca, Prostate—PC-3 and Prostate—DU-145). The acetone extract was subjected to bioactivity guided fractionation. Anti-proliferation and clonogenic activity of the isolated compounds were tested. The WST-1 assay was used for the anti-proliferation activity, while the standard clonogenic test was used to determine the clonogenic activity. Results The acetone extract of Vernonia guineensis Benth. demonstrated in vitro activity ranging from IC50 4–26 μg/mL against the 10 cell lines. Activity guided fractionation of this extract yielded two sesquiterpene lactones, isolated for the first time from the genus Vernonia. The compounds were characterized using spectroscopic experiments, including a combination of 1D and 2D NMR data. Vernopicrin (1) and Vernomelitensin (2) demonstrated in vitro activity against human cancer cell lines with IC50 ranging from 0.35–2.04 μM (P Conclusion The cytotoxicity demonstrated by the crude extract and isolated sesquiterpenes against cancer cell lines highlights the medicinal potential of V. guineensis. The selective anti-proliferation and dose dependent anticlonogenic activities suggest that the identified sesquiterpenes could be potential antitumor agents.
Berit Smestad Paulsen - One of the best experts on this subject based on the ideXlab platform.
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chemical and biological characterization of polysaccharides from wild and cultivated roots of Vernonia kotschyana
Journal of Ethnopharmacology, 2012Co-Authors: Kari Tvete Inngjerdingen, Terje E Michaelsen, Drissa Diallo, S Meskini, Ingvild Austarheim, Ngolo Ballo, Marit Inngjerdingen, Berit Smestad PaulsenAbstract:Abstract Ethnopharmacological relevance In Malian traditional medicine the roots of Vernonia kotschyana are used for treating gastric ulcer and gastritis. In 2006, 9000 kg of roots from Vernonia kotschyana were used to produce Gastrosedal, an ameliorated traditional medicine in Mali. Harvesting from the wild, the main source of raw material, is causing a growing concern of diminishing populations of the plant, and Vernonia kotschyana is now being cultivated in several areas around Mali. In the current study the structures and bioactive properties of isolated polysaccharides from wild and cultivated Vernonia kotschyana were compared. Materials and methods Pectin- and inulin-type polysaccharides were isolated from the roots of cultivated and wild Vernonia kotschyana . The isolated polysaccharides were investigated regarding their chemical compositions, and for their abilities to fixate human complement and activate macrophages from a mouse macrophage cell line. Results No significant differences in the carbohydrate composition of the fractions isolated from the cultivated versus the wild roots were observed. A previously reported pectic arabinogalactan Vk2a was found in both the cultivated and the wild roots in this study, and exhibited potent complement fixation activity, and a moderate activation of macrophages. Conclusions The present study has shown that the cultivated roots of Vernonia kotschyana contain the same types of bioactive polysaccharides as the wild roots. It is therefore preliminarily feasible for the cultivated roots of Vernonia kotschyana to be used as a herbal medicine to replace the wild roots.
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isolation partial characterisation and immunomodulating activities of polysaccharides from Vernonia kotschyana sch bip ex walp
Journal of Ethnopharmacology, 2004Co-Authors: Cecilie Sogn Nergard, Hiroaki Kiyohara, Haruki Yamada, Terje E Michaelsen, Drissa Diallo, Tsukasa Matsumoto, Karl Egil Malterud, Berit Smestad PaulsenAbstract:Abstract The roots from Vernonia kotschyana Sch. Bip. ex Walp. (Baccharoides adoensis var. kotschyana (Sch. Bip. ex Walp.) M.A. Isawumi, G.El-Ghazaly & B. Nordenstam) (Asteraceae) are used in Malian folk medicine for the treatment of gastritis, gastro duodenal ulcers, as an aid to ameliorate digestion and as a wound healing remedy. Since a common feature among these conditions is related to immune responses, immunomodulating activities of fractions isolated from both the 50 °C and the 100 °C water extracts from Vernonia kotschyana were investigated in this study. The active principles were identified as acidic polysaccharide fractions, containing pectic arabinogalactan type II structures, which showed both complement fixing ability and T-cell independent induction of B-cell proliferation in vitro. Some activity was also observed on macrophages. The present study may provide additional support for the popular use of this plant to improve intestinal health.
Drissa Diallo - One of the best experts on this subject based on the ideXlab platform.
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chemical and biological characterization of polysaccharides from wild and cultivated roots of Vernonia kotschyana
Journal of Ethnopharmacology, 2012Co-Authors: Kari Tvete Inngjerdingen, Terje E Michaelsen, Drissa Diallo, S Meskini, Ingvild Austarheim, Ngolo Ballo, Marit Inngjerdingen, Berit Smestad PaulsenAbstract:Abstract Ethnopharmacological relevance In Malian traditional medicine the roots of Vernonia kotschyana are used for treating gastric ulcer and gastritis. In 2006, 9000 kg of roots from Vernonia kotschyana were used to produce Gastrosedal, an ameliorated traditional medicine in Mali. Harvesting from the wild, the main source of raw material, is causing a growing concern of diminishing populations of the plant, and Vernonia kotschyana is now being cultivated in several areas around Mali. In the current study the structures and bioactive properties of isolated polysaccharides from wild and cultivated Vernonia kotschyana were compared. Materials and methods Pectin- and inulin-type polysaccharides were isolated from the roots of cultivated and wild Vernonia kotschyana . The isolated polysaccharides were investigated regarding their chemical compositions, and for their abilities to fixate human complement and activate macrophages from a mouse macrophage cell line. Results No significant differences in the carbohydrate composition of the fractions isolated from the cultivated versus the wild roots were observed. A previously reported pectic arabinogalactan Vk2a was found in both the cultivated and the wild roots in this study, and exhibited potent complement fixation activity, and a moderate activation of macrophages. Conclusions The present study has shown that the cultivated roots of Vernonia kotschyana contain the same types of bioactive polysaccharides as the wild roots. It is therefore preliminarily feasible for the cultivated roots of Vernonia kotschyana to be used as a herbal medicine to replace the wild roots.
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structures and structure activity relationships of three mitogenic and complement fixing pectic arabinogalactans from the malian antiulcer plants cochlospermum tinctorium a rich and Vernonia kotschyana sch bip ex walp
Biomacromolecules, 2006Co-Authors: Cecilie Sogn Nergard, Hiroaki Kiyohara, Haruki Yamada, Terje E Michaelsen, James C Reynolds, Jane Thomasoates, Tsukasa Matsumoto, Trushar R Patel, Dirk Petersen, Drissa DialloAbstract:Structures of three pectic arabinogalactans, one from Vernonia kotschyana (Vk2a) and two from Cochlospermum tinctorium (Ct50A1 and Ct50A2), and their complement fixation and induction of B cell pro...
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isolation partial characterisation and immunomodulating activities of polysaccharides from Vernonia kotschyana sch bip ex walp
Journal of Ethnopharmacology, 2004Co-Authors: Cecilie Sogn Nergard, Hiroaki Kiyohara, Haruki Yamada, Terje E Michaelsen, Drissa Diallo, Tsukasa Matsumoto, Karl Egil Malterud, Berit Smestad PaulsenAbstract:Abstract The roots from Vernonia kotschyana Sch. Bip. ex Walp. (Baccharoides adoensis var. kotschyana (Sch. Bip. ex Walp.) M.A. Isawumi, G.El-Ghazaly & B. Nordenstam) (Asteraceae) are used in Malian folk medicine for the treatment of gastritis, gastro duodenal ulcers, as an aid to ameliorate digestion and as a wound healing remedy. Since a common feature among these conditions is related to immune responses, immunomodulating activities of fractions isolated from both the 50 °C and the 100 °C water extracts from Vernonia kotschyana were investigated in this study. The active principles were identified as acidic polysaccharide fractions, containing pectic arabinogalactan type II structures, which showed both complement fixing ability and T-cell independent induction of B-cell proliferation in vitro. Some activity was also observed on macrophages. The present study may provide additional support for the popular use of this plant to improve intestinal health.
Terje E Michaelsen - One of the best experts on this subject based on the ideXlab platform.
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chemical and biological characterization of polysaccharides from wild and cultivated roots of Vernonia kotschyana
Journal of Ethnopharmacology, 2012Co-Authors: Kari Tvete Inngjerdingen, Terje E Michaelsen, Drissa Diallo, S Meskini, Ingvild Austarheim, Ngolo Ballo, Marit Inngjerdingen, Berit Smestad PaulsenAbstract:Abstract Ethnopharmacological relevance In Malian traditional medicine the roots of Vernonia kotschyana are used for treating gastric ulcer and gastritis. In 2006, 9000 kg of roots from Vernonia kotschyana were used to produce Gastrosedal, an ameliorated traditional medicine in Mali. Harvesting from the wild, the main source of raw material, is causing a growing concern of diminishing populations of the plant, and Vernonia kotschyana is now being cultivated in several areas around Mali. In the current study the structures and bioactive properties of isolated polysaccharides from wild and cultivated Vernonia kotschyana were compared. Materials and methods Pectin- and inulin-type polysaccharides were isolated from the roots of cultivated and wild Vernonia kotschyana . The isolated polysaccharides were investigated regarding their chemical compositions, and for their abilities to fixate human complement and activate macrophages from a mouse macrophage cell line. Results No significant differences in the carbohydrate composition of the fractions isolated from the cultivated versus the wild roots were observed. A previously reported pectic arabinogalactan Vk2a was found in both the cultivated and the wild roots in this study, and exhibited potent complement fixation activity, and a moderate activation of macrophages. Conclusions The present study has shown that the cultivated roots of Vernonia kotschyana contain the same types of bioactive polysaccharides as the wild roots. It is therefore preliminarily feasible for the cultivated roots of Vernonia kotschyana to be used as a herbal medicine to replace the wild roots.
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structures and structure activity relationships of three mitogenic and complement fixing pectic arabinogalactans from the malian antiulcer plants cochlospermum tinctorium a rich and Vernonia kotschyana sch bip ex walp
Biomacromolecules, 2006Co-Authors: Cecilie Sogn Nergard, Hiroaki Kiyohara, Haruki Yamada, Terje E Michaelsen, James C Reynolds, Jane Thomasoates, Tsukasa Matsumoto, Trushar R Patel, Dirk Petersen, Drissa DialloAbstract:Structures of three pectic arabinogalactans, one from Vernonia kotschyana (Vk2a) and two from Cochlospermum tinctorium (Ct50A1 and Ct50A2), and their complement fixation and induction of B cell pro...
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isolation partial characterisation and immunomodulating activities of polysaccharides from Vernonia kotschyana sch bip ex walp
Journal of Ethnopharmacology, 2004Co-Authors: Cecilie Sogn Nergard, Hiroaki Kiyohara, Haruki Yamada, Terje E Michaelsen, Drissa Diallo, Tsukasa Matsumoto, Karl Egil Malterud, Berit Smestad PaulsenAbstract:Abstract The roots from Vernonia kotschyana Sch. Bip. ex Walp. (Baccharoides adoensis var. kotschyana (Sch. Bip. ex Walp.) M.A. Isawumi, G.El-Ghazaly & B. Nordenstam) (Asteraceae) are used in Malian folk medicine for the treatment of gastritis, gastro duodenal ulcers, as an aid to ameliorate digestion and as a wound healing remedy. Since a common feature among these conditions is related to immune responses, immunomodulating activities of fractions isolated from both the 50 °C and the 100 °C water extracts from Vernonia kotschyana were investigated in this study. The active principles were identified as acidic polysaccharide fractions, containing pectic arabinogalactan type II structures, which showed both complement fixing ability and T-cell independent induction of B-cell proliferation in vitro. Some activity was also observed on macrophages. The present study may provide additional support for the popular use of this plant to improve intestinal health.
