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Alvaro Viljoen - One of the best experts on this subject based on the ideXlab platform.
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mid infrared spectroscopy and short wave infrared hyperspectral imaging a novel approach in the qualitative assessment of Harpagophytum procumbens and h zeyheri devil s claw
Phytochemistry Letters, 2014Co-Authors: Nontobeko Mncwangi, Ilze Vermaak, Alvaro ViljoenAbstract:Abstract Harpagophytum procumbens (Burch.) DC. ex Meisn. subsp. procumbens (Pedaliaceae) is an important African medicinal plant growing in the Kalahari region of southern Africa. This species, together with its close taxonomic ally Harpagophytum zeyheri are collectively referred to as Devil's Claw and are used interchangeably for the treatment of inflammation-related disorders. Although the two taxa are botanically and chemically similar, H. zeyheri contains lower levels of harpagoside and these two species have not been proven to exhibit equipotent pharmacological activity. Due to these taxonomic similarities, effective quality control methods are required to distinguish between the two species. Differentiation between the two species was achieved using single point mid-infrared spectroscopy in combination with chemometric data analysis. The orthogonal projections to latent structures discriminant analysis (OPLS-DA) model had good predictive ability, as illustrated by the model statistics: R2X (cum predictive + orthogonal) = 0.86 and Q2 (cum) = 0.63. Short wave infrared (SWIR) hyperspectral imaging could distinguish between the two species with acceptable model statistics: R2X and R2Y of 0.99 and 0.78, respectively. This study demonstrated that both MIR single point spectroscopy and SWIR hyperspectral imaging coupled with chemometric modelling are reliable and rapid methods to determine the authenticity of Harpagophytum spp.
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Mid-infrared spectroscopy and short wave infrared hyperspectral imaging—A novel approach in the qualitative assessment of Harpagophytum procumbens and H. zeyheri (Devil's Claw)
Phytochemistry Letters, 2014Co-Authors: Nontobeko Mncwangi, Ilze Vermaak, Alvaro ViljoenAbstract:Abstract Harpagophytum procumbens (Burch.) DC. ex Meisn. subsp. procumbens (Pedaliaceae) is an important African medicinal plant growing in the Kalahari region of southern Africa. This species, together with its close taxonomic ally Harpagophytum zeyheri are collectively referred to as Devil's Claw and are used interchangeably for the treatment of inflammation-related disorders. Although the two taxa are botanically and chemically similar, H. zeyheri contains lower levels of harpagoside and these two species have not been proven to exhibit equipotent pharmacological activity. Due to these taxonomic similarities, effective quality control methods are required to distinguish between the two species. Differentiation between the two species was achieved using single point mid-infrared spectroscopy in combination with chemometric data analysis. The orthogonal projections to latent structures discriminant analysis (OPLS-DA) model had good predictive ability, as illustrated by the model statistics: R2X (cum predictive + orthogonal) = 0.86 and Q2 (cum) = 0.63. Short wave infrared (SWIR) hyperspectral imaging could distinguish between the two species with acceptable model statistics: R2X and R2Y of 0.99 and 0.78, respectively. This study demonstrated that both MIR single point spectroscopy and SWIR hyperspectral imaging coupled with chemometric modelling are reliable and rapid methods to determine the authenticity of Harpagophytum spp.
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What the devil is in your phytomedicine? Exploring species substitution in Harpagophytum through chemometric modeling of 1H-NMR and UHPLC-MS datasets.
Phytochemistry, 2014Co-Authors: Nontobeko Mncwangi, Ilze Vermaak, Alvaro Viljoen, Jianping Zhao, Wei Chen, Ikhlas A. KhanAbstract:Harpagophytum procumbens (Pedaliaceae) and its close taxonomical ally Harpagophytum zeyheri, indige- nous to southern Africa, are being harvested for exportation to Europe where phytomedicines are devel- oped to treat inflammation-related disorders. The phytochemical variation within and between natural populations of H. procumbens (n = 241) and H. zeyheri (n = 107) was explored using proton nuclear mag- netic resonance ( 1 H-NMR) and ultra-high performance liquid chromatography coupled to mass spec- trometry (UHPLC-MS) in combination with multivariate data analysis methods. The UHPLC-MS results revealed significant variation in the harpagoside content: H. procumbens (0.17-4.37%); H. zeyheri (0.00-3.07%). Only 41% of the H. procumbens samples and 17% of the H. zeyheri samples met the pharma- copoeial specification of P1.2%. Both principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA) indicated separation based on species (UHPLC-MS data OPLS-DA model statistics: R 2
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devil s claw a review of the ethnobotany phytochemistry and biological activity of Harpagophytum procumbens
Journal of Ethnopharmacology, 2012Co-Authors: Nontobeko Mncwangi, Weiyang Chen, Ilze Vermaak, Alvaro Viljoen, Nigel GerickeAbstract:ETHNOPHARMACOLOGICAL RELEVANCE: Harpagophytum procumbens subps. procumbens (Burch.) DC. ex Meisn. (Pedaliaceae) is an important traditional medicine growing in the Kalahari region of southern Africa where it is consumed as a general health tonic and for treating diverse ailments including arthritis, pain, fever, ulcers and boils. AIM OF THE REVIEW: To provide a comprehensive overview of the ethnobotany, phytochemistry and biological activity of H. procumbens and possibly make recommendations for further research. MATERIALS AND METHODS: Peer-reviewed articles on H. procumbens were acquired on Scopus, ScienceDirect and SciFinder, there was no specific timeline set for the search. A focus group discussion was held with different communities in Botswana to further understand ethnobotanical uses of the plant. RESULTS: Harpogophytum procumbens is used for a wide variety of health conditions in the form of infusions, decoctions, tinctures, powders and extracts. In addition to the common local use for arthritis and pain, other ethnomedicinal uses include dyspepsia, fever, blood diseases, urinary tract infections, postpartum pain, sprains, sores, ulcers and boils. Scientific studies revealed that H. procumbens exhibits analgesic, anti-oxidant, anti-diabetic, anti-epileptic, antimicrobial and antimalarial activities amongst others. Iridoid glycosides and phenylpropanoid glycosides have been the focus of phytochemical investigations as the biological activity has been ascribed to the iridoid glycosides (such as harpagoside and harpagide), which are common in nature and are known to possess anti-inflammatory activity. In addition, it has been shown that the hydrolysed products of harpagoside and harpagide have more pronounced anti-inflammatory activity when compared to the unhydrolysed compounds. Harpagophytum zeyheri is a close taxonomic ally of H. procumbens but H. procumbens is the favoured species of commerce, and contains higher levels of the pharmacologically active constituents. The two are used interchangeably and H. procumbens raw material is often intentionally adulterated with H. zeyheri and this may impact on the efficacy of inadequately controlled health products. The main exporter of this highly commercialised plant is Namibia. In 2009 alone, Harpagophytum exports were worth approximately €1.06 million. The high demand for health products based on this plant has led to over-harvesting, raising concerns about sustainability. Although only the secondary tubers are utilised commercially, the whole plant is often destroyed during harvesting. CONCLUSIONS: Harpagophytum procumbens is used to treat a wide range of ailments. Some of the ethnobotanical claims have been confirmed through in vitro studies, however, when the constituents deemed to be the biologically active compounds were isolated the efficacy was lower than that of the whole extract. This necessitates the use of a different approach where all the metabolites are considered using a robust method such as spectroscopy; the phytochemical data can then be superimposed on the biological activity. Furthermore, there is a need to develop rapid and efficient quality control methods for both raw materials and products because the orthodox methods in current use are time-consuming and labour intensive.
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Devil's Claw—A review of the ethnobotany, phytochemistry and biological activity of Harpagophytum procumbens
Journal of Ethnopharmacology, 2012Co-Authors: Nontobeko Mncwangi, Weiyang Chen, Ilze Vermaak, Alvaro Viljoen, Nigel GerickeAbstract:ETHNOPHARMACOLOGICAL RELEVANCE: Harpagophytum procumbens subps. procumbens (Burch.) DC. ex Meisn. (Pedaliaceae) is an important traditional medicine growing in the Kalahari region of southern Africa where it is consumed as a general health tonic and for treating diverse ailments including arthritis, pain, fever, ulcers and boils. AIM OF THE REVIEW: To provide a comprehensive overview of the ethnobotany, phytochemistry and biological activity of H. procumbens and possibly make recommendations for further research. MATERIALS AND METHODS: Peer-reviewed articles on H. procumbens were acquired on Scopus, ScienceDirect and SciFinder, there was no specific timeline set for the search. A focus group discussion was held with different communities in Botswana to further understand ethnobotanical uses of the plant. RESULTS: Harpogophytum procumbens is used for a wide variety of health conditions in the form of infusions, decoctions, tinctures, powders and extracts. In addition to the common local use for arthritis and pain, other ethnomedicinal uses include dyspepsia, fever, blood diseases, urinary tract infections, postpartum pain, sprains, sores, ulcers and boils. Scientific studies revealed that H. procumbens exhibits analgesic, anti-oxidant, anti-diabetic, anti-epileptic, antimicrobial and antimalarial activities amongst others. Iridoid glycosides and phenylpropanoid glycosides have been the focus of phytochemical investigations as the biological activity has been ascribed to the iridoid glycosides (such as harpagoside and harpagide), which are common in nature and are known to possess anti-inflammatory activity. In addition, it has been shown that the hydrolysed products of harpagoside and harpagide have more pronounced anti-inflammatory activity when compared to the unhydrolysed compounds. Harpagophytum zeyheri is a close taxonomic ally of H. procumbens but H. procumbens is the favoured species of commerce, and contains higher levels of the pharmacologically active constituents. The two are used interchangeably and H. procumbens raw material is often intentionally adulterated with H. zeyheri and this may impact on the efficacy of inadequately controlled health products. The main exporter of this highly commercialised plant is Namibia. In 2009 alone, Harpagophytum exports were worth approximately €1.06 million. The high demand for health products based on this plant has led to over-harvesting, raising concerns about sustainability. Although only the secondary tubers are utilised commercially, the whole plant is often destroyed during harvesting. CONCLUSIONS: Harpagophytum procumbens is used to treat a wide range of ailments. Some of the ethnobotanical claims have been confirmed through in vitro studies, however, when the constituents deemed to be the biologically active compounds were isolated the efficacy was lower than that of the whole extract. This necessitates the use of a different approach where all the metabolites are considered using a robust method such as spectroscopy; the phytochemical data can then be superimposed on the biological activity. Furthermore, there is a need to develop rapid and efficient quality control methods for both raw materials and products because the orthodox methods in current use are time-consuming and labour intensive.
Nontobeko Mncwangi - One of the best experts on this subject based on the ideXlab platform.
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mid infrared spectroscopy and short wave infrared hyperspectral imaging a novel approach in the qualitative assessment of Harpagophytum procumbens and h zeyheri devil s claw
Phytochemistry Letters, 2014Co-Authors: Nontobeko Mncwangi, Ilze Vermaak, Alvaro ViljoenAbstract:Abstract Harpagophytum procumbens (Burch.) DC. ex Meisn. subsp. procumbens (Pedaliaceae) is an important African medicinal plant growing in the Kalahari region of southern Africa. This species, together with its close taxonomic ally Harpagophytum zeyheri are collectively referred to as Devil's Claw and are used interchangeably for the treatment of inflammation-related disorders. Although the two taxa are botanically and chemically similar, H. zeyheri contains lower levels of harpagoside and these two species have not been proven to exhibit equipotent pharmacological activity. Due to these taxonomic similarities, effective quality control methods are required to distinguish between the two species. Differentiation between the two species was achieved using single point mid-infrared spectroscopy in combination with chemometric data analysis. The orthogonal projections to latent structures discriminant analysis (OPLS-DA) model had good predictive ability, as illustrated by the model statistics: R2X (cum predictive + orthogonal) = 0.86 and Q2 (cum) = 0.63. Short wave infrared (SWIR) hyperspectral imaging could distinguish between the two species with acceptable model statistics: R2X and R2Y of 0.99 and 0.78, respectively. This study demonstrated that both MIR single point spectroscopy and SWIR hyperspectral imaging coupled with chemometric modelling are reliable and rapid methods to determine the authenticity of Harpagophytum spp.
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Mid-infrared spectroscopy and short wave infrared hyperspectral imaging—A novel approach in the qualitative assessment of Harpagophytum procumbens and H. zeyheri (Devil's Claw)
Phytochemistry Letters, 2014Co-Authors: Nontobeko Mncwangi, Ilze Vermaak, Alvaro ViljoenAbstract:Abstract Harpagophytum procumbens (Burch.) DC. ex Meisn. subsp. procumbens (Pedaliaceae) is an important African medicinal plant growing in the Kalahari region of southern Africa. This species, together with its close taxonomic ally Harpagophytum zeyheri are collectively referred to as Devil's Claw and are used interchangeably for the treatment of inflammation-related disorders. Although the two taxa are botanically and chemically similar, H. zeyheri contains lower levels of harpagoside and these two species have not been proven to exhibit equipotent pharmacological activity. Due to these taxonomic similarities, effective quality control methods are required to distinguish between the two species. Differentiation between the two species was achieved using single point mid-infrared spectroscopy in combination with chemometric data analysis. The orthogonal projections to latent structures discriminant analysis (OPLS-DA) model had good predictive ability, as illustrated by the model statistics: R2X (cum predictive + orthogonal) = 0.86 and Q2 (cum) = 0.63. Short wave infrared (SWIR) hyperspectral imaging could distinguish between the two species with acceptable model statistics: R2X and R2Y of 0.99 and 0.78, respectively. This study demonstrated that both MIR single point spectroscopy and SWIR hyperspectral imaging coupled with chemometric modelling are reliable and rapid methods to determine the authenticity of Harpagophytum spp.
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What the devil is in your phytomedicine? Exploring species substitution in Harpagophytum through chemometric modeling of 1H-NMR and UHPLC-MS datasets.
Phytochemistry, 2014Co-Authors: Nontobeko Mncwangi, Ilze Vermaak, Alvaro Viljoen, Jianping Zhao, Wei Chen, Ikhlas A. KhanAbstract:Harpagophytum procumbens (Pedaliaceae) and its close taxonomical ally Harpagophytum zeyheri, indige- nous to southern Africa, are being harvested for exportation to Europe where phytomedicines are devel- oped to treat inflammation-related disorders. The phytochemical variation within and between natural populations of H. procumbens (n = 241) and H. zeyheri (n = 107) was explored using proton nuclear mag- netic resonance ( 1 H-NMR) and ultra-high performance liquid chromatography coupled to mass spec- trometry (UHPLC-MS) in combination with multivariate data analysis methods. The UHPLC-MS results revealed significant variation in the harpagoside content: H. procumbens (0.17-4.37%); H. zeyheri (0.00-3.07%). Only 41% of the H. procumbens samples and 17% of the H. zeyheri samples met the pharma- copoeial specification of P1.2%. Both principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA) indicated separation based on species (UHPLC-MS data OPLS-DA model statistics: R 2
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devil s claw a review of the ethnobotany phytochemistry and biological activity of Harpagophytum procumbens
Journal of Ethnopharmacology, 2012Co-Authors: Nontobeko Mncwangi, Weiyang Chen, Ilze Vermaak, Alvaro Viljoen, Nigel GerickeAbstract:ETHNOPHARMACOLOGICAL RELEVANCE: Harpagophytum procumbens subps. procumbens (Burch.) DC. ex Meisn. (Pedaliaceae) is an important traditional medicine growing in the Kalahari region of southern Africa where it is consumed as a general health tonic and for treating diverse ailments including arthritis, pain, fever, ulcers and boils. AIM OF THE REVIEW: To provide a comprehensive overview of the ethnobotany, phytochemistry and biological activity of H. procumbens and possibly make recommendations for further research. MATERIALS AND METHODS: Peer-reviewed articles on H. procumbens were acquired on Scopus, ScienceDirect and SciFinder, there was no specific timeline set for the search. A focus group discussion was held with different communities in Botswana to further understand ethnobotanical uses of the plant. RESULTS: Harpogophytum procumbens is used for a wide variety of health conditions in the form of infusions, decoctions, tinctures, powders and extracts. In addition to the common local use for arthritis and pain, other ethnomedicinal uses include dyspepsia, fever, blood diseases, urinary tract infections, postpartum pain, sprains, sores, ulcers and boils. Scientific studies revealed that H. procumbens exhibits analgesic, anti-oxidant, anti-diabetic, anti-epileptic, antimicrobial and antimalarial activities amongst others. Iridoid glycosides and phenylpropanoid glycosides have been the focus of phytochemical investigations as the biological activity has been ascribed to the iridoid glycosides (such as harpagoside and harpagide), which are common in nature and are known to possess anti-inflammatory activity. In addition, it has been shown that the hydrolysed products of harpagoside and harpagide have more pronounced anti-inflammatory activity when compared to the unhydrolysed compounds. Harpagophytum zeyheri is a close taxonomic ally of H. procumbens but H. procumbens is the favoured species of commerce, and contains higher levels of the pharmacologically active constituents. The two are used interchangeably and H. procumbens raw material is often intentionally adulterated with H. zeyheri and this may impact on the efficacy of inadequately controlled health products. The main exporter of this highly commercialised plant is Namibia. In 2009 alone, Harpagophytum exports were worth approximately €1.06 million. The high demand for health products based on this plant has led to over-harvesting, raising concerns about sustainability. Although only the secondary tubers are utilised commercially, the whole plant is often destroyed during harvesting. CONCLUSIONS: Harpagophytum procumbens is used to treat a wide range of ailments. Some of the ethnobotanical claims have been confirmed through in vitro studies, however, when the constituents deemed to be the biologically active compounds were isolated the efficacy was lower than that of the whole extract. This necessitates the use of a different approach where all the metabolites are considered using a robust method such as spectroscopy; the phytochemical data can then be superimposed on the biological activity. Furthermore, there is a need to develop rapid and efficient quality control methods for both raw materials and products because the orthodox methods in current use are time-consuming and labour intensive.
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Devil's Claw—A review of the ethnobotany, phytochemistry and biological activity of Harpagophytum procumbens
Journal of Ethnopharmacology, 2012Co-Authors: Nontobeko Mncwangi, Weiyang Chen, Ilze Vermaak, Alvaro Viljoen, Nigel GerickeAbstract:ETHNOPHARMACOLOGICAL RELEVANCE: Harpagophytum procumbens subps. procumbens (Burch.) DC. ex Meisn. (Pedaliaceae) is an important traditional medicine growing in the Kalahari region of southern Africa where it is consumed as a general health tonic and for treating diverse ailments including arthritis, pain, fever, ulcers and boils. AIM OF THE REVIEW: To provide a comprehensive overview of the ethnobotany, phytochemistry and biological activity of H. procumbens and possibly make recommendations for further research. MATERIALS AND METHODS: Peer-reviewed articles on H. procumbens were acquired on Scopus, ScienceDirect and SciFinder, there was no specific timeline set for the search. A focus group discussion was held with different communities in Botswana to further understand ethnobotanical uses of the plant. RESULTS: Harpogophytum procumbens is used for a wide variety of health conditions in the form of infusions, decoctions, tinctures, powders and extracts. In addition to the common local use for arthritis and pain, other ethnomedicinal uses include dyspepsia, fever, blood diseases, urinary tract infections, postpartum pain, sprains, sores, ulcers and boils. Scientific studies revealed that H. procumbens exhibits analgesic, anti-oxidant, anti-diabetic, anti-epileptic, antimicrobial and antimalarial activities amongst others. Iridoid glycosides and phenylpropanoid glycosides have been the focus of phytochemical investigations as the biological activity has been ascribed to the iridoid glycosides (such as harpagoside and harpagide), which are common in nature and are known to possess anti-inflammatory activity. In addition, it has been shown that the hydrolysed products of harpagoside and harpagide have more pronounced anti-inflammatory activity when compared to the unhydrolysed compounds. Harpagophytum zeyheri is a close taxonomic ally of H. procumbens but H. procumbens is the favoured species of commerce, and contains higher levels of the pharmacologically active constituents. The two are used interchangeably and H. procumbens raw material is often intentionally adulterated with H. zeyheri and this may impact on the efficacy of inadequately controlled health products. The main exporter of this highly commercialised plant is Namibia. In 2009 alone, Harpagophytum exports were worth approximately €1.06 million. The high demand for health products based on this plant has led to over-harvesting, raising concerns about sustainability. Although only the secondary tubers are utilised commercially, the whole plant is often destroyed during harvesting. CONCLUSIONS: Harpagophytum procumbens is used to treat a wide range of ailments. Some of the ethnobotanical claims have been confirmed through in vitro studies, however, when the constituents deemed to be the biologically active compounds were isolated the efficacy was lower than that of the whole extract. This necessitates the use of a different approach where all the metabolites are considered using a robust method such as spectroscopy; the phytochemical data can then be superimposed on the biological activity. Furthermore, there is a need to develop rapid and efficient quality control methods for both raw materials and products because the orthodox methods in current use are time-consuming and labour intensive.
Ilze Vermaak - One of the best experts on this subject based on the ideXlab platform.
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mid infrared spectroscopy and short wave infrared hyperspectral imaging a novel approach in the qualitative assessment of Harpagophytum procumbens and h zeyheri devil s claw
Phytochemistry Letters, 2014Co-Authors: Nontobeko Mncwangi, Ilze Vermaak, Alvaro ViljoenAbstract:Abstract Harpagophytum procumbens (Burch.) DC. ex Meisn. subsp. procumbens (Pedaliaceae) is an important African medicinal plant growing in the Kalahari region of southern Africa. This species, together with its close taxonomic ally Harpagophytum zeyheri are collectively referred to as Devil's Claw and are used interchangeably for the treatment of inflammation-related disorders. Although the two taxa are botanically and chemically similar, H. zeyheri contains lower levels of harpagoside and these two species have not been proven to exhibit equipotent pharmacological activity. Due to these taxonomic similarities, effective quality control methods are required to distinguish between the two species. Differentiation between the two species was achieved using single point mid-infrared spectroscopy in combination with chemometric data analysis. The orthogonal projections to latent structures discriminant analysis (OPLS-DA) model had good predictive ability, as illustrated by the model statistics: R2X (cum predictive + orthogonal) = 0.86 and Q2 (cum) = 0.63. Short wave infrared (SWIR) hyperspectral imaging could distinguish between the two species with acceptable model statistics: R2X and R2Y of 0.99 and 0.78, respectively. This study demonstrated that both MIR single point spectroscopy and SWIR hyperspectral imaging coupled with chemometric modelling are reliable and rapid methods to determine the authenticity of Harpagophytum spp.
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Mid-infrared spectroscopy and short wave infrared hyperspectral imaging—A novel approach in the qualitative assessment of Harpagophytum procumbens and H. zeyheri (Devil's Claw)
Phytochemistry Letters, 2014Co-Authors: Nontobeko Mncwangi, Ilze Vermaak, Alvaro ViljoenAbstract:Abstract Harpagophytum procumbens (Burch.) DC. ex Meisn. subsp. procumbens (Pedaliaceae) is an important African medicinal plant growing in the Kalahari region of southern Africa. This species, together with its close taxonomic ally Harpagophytum zeyheri are collectively referred to as Devil's Claw and are used interchangeably for the treatment of inflammation-related disorders. Although the two taxa are botanically and chemically similar, H. zeyheri contains lower levels of harpagoside and these two species have not been proven to exhibit equipotent pharmacological activity. Due to these taxonomic similarities, effective quality control methods are required to distinguish between the two species. Differentiation between the two species was achieved using single point mid-infrared spectroscopy in combination with chemometric data analysis. The orthogonal projections to latent structures discriminant analysis (OPLS-DA) model had good predictive ability, as illustrated by the model statistics: R2X (cum predictive + orthogonal) = 0.86 and Q2 (cum) = 0.63. Short wave infrared (SWIR) hyperspectral imaging could distinguish between the two species with acceptable model statistics: R2X and R2Y of 0.99 and 0.78, respectively. This study demonstrated that both MIR single point spectroscopy and SWIR hyperspectral imaging coupled with chemometric modelling are reliable and rapid methods to determine the authenticity of Harpagophytum spp.
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What the devil is in your phytomedicine? Exploring species substitution in Harpagophytum through chemometric modeling of 1H-NMR and UHPLC-MS datasets.
Phytochemistry, 2014Co-Authors: Nontobeko Mncwangi, Ilze Vermaak, Alvaro Viljoen, Jianping Zhao, Wei Chen, Ikhlas A. KhanAbstract:Harpagophytum procumbens (Pedaliaceae) and its close taxonomical ally Harpagophytum zeyheri, indige- nous to southern Africa, are being harvested for exportation to Europe where phytomedicines are devel- oped to treat inflammation-related disorders. The phytochemical variation within and between natural populations of H. procumbens (n = 241) and H. zeyheri (n = 107) was explored using proton nuclear mag- netic resonance ( 1 H-NMR) and ultra-high performance liquid chromatography coupled to mass spec- trometry (UHPLC-MS) in combination with multivariate data analysis methods. The UHPLC-MS results revealed significant variation in the harpagoside content: H. procumbens (0.17-4.37%); H. zeyheri (0.00-3.07%). Only 41% of the H. procumbens samples and 17% of the H. zeyheri samples met the pharma- copoeial specification of P1.2%. Both principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA) indicated separation based on species (UHPLC-MS data OPLS-DA model statistics: R 2
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devil s claw a review of the ethnobotany phytochemistry and biological activity of Harpagophytum procumbens
Journal of Ethnopharmacology, 2012Co-Authors: Nontobeko Mncwangi, Weiyang Chen, Ilze Vermaak, Alvaro Viljoen, Nigel GerickeAbstract:ETHNOPHARMACOLOGICAL RELEVANCE: Harpagophytum procumbens subps. procumbens (Burch.) DC. ex Meisn. (Pedaliaceae) is an important traditional medicine growing in the Kalahari region of southern Africa where it is consumed as a general health tonic and for treating diverse ailments including arthritis, pain, fever, ulcers and boils. AIM OF THE REVIEW: To provide a comprehensive overview of the ethnobotany, phytochemistry and biological activity of H. procumbens and possibly make recommendations for further research. MATERIALS AND METHODS: Peer-reviewed articles on H. procumbens were acquired on Scopus, ScienceDirect and SciFinder, there was no specific timeline set for the search. A focus group discussion was held with different communities in Botswana to further understand ethnobotanical uses of the plant. RESULTS: Harpogophytum procumbens is used for a wide variety of health conditions in the form of infusions, decoctions, tinctures, powders and extracts. In addition to the common local use for arthritis and pain, other ethnomedicinal uses include dyspepsia, fever, blood diseases, urinary tract infections, postpartum pain, sprains, sores, ulcers and boils. Scientific studies revealed that H. procumbens exhibits analgesic, anti-oxidant, anti-diabetic, anti-epileptic, antimicrobial and antimalarial activities amongst others. Iridoid glycosides and phenylpropanoid glycosides have been the focus of phytochemical investigations as the biological activity has been ascribed to the iridoid glycosides (such as harpagoside and harpagide), which are common in nature and are known to possess anti-inflammatory activity. In addition, it has been shown that the hydrolysed products of harpagoside and harpagide have more pronounced anti-inflammatory activity when compared to the unhydrolysed compounds. Harpagophytum zeyheri is a close taxonomic ally of H. procumbens but H. procumbens is the favoured species of commerce, and contains higher levels of the pharmacologically active constituents. The two are used interchangeably and H. procumbens raw material is often intentionally adulterated with H. zeyheri and this may impact on the efficacy of inadequately controlled health products. The main exporter of this highly commercialised plant is Namibia. In 2009 alone, Harpagophytum exports were worth approximately €1.06 million. The high demand for health products based on this plant has led to over-harvesting, raising concerns about sustainability. Although only the secondary tubers are utilised commercially, the whole plant is often destroyed during harvesting. CONCLUSIONS: Harpagophytum procumbens is used to treat a wide range of ailments. Some of the ethnobotanical claims have been confirmed through in vitro studies, however, when the constituents deemed to be the biologically active compounds were isolated the efficacy was lower than that of the whole extract. This necessitates the use of a different approach where all the metabolites are considered using a robust method such as spectroscopy; the phytochemical data can then be superimposed on the biological activity. Furthermore, there is a need to develop rapid and efficient quality control methods for both raw materials and products because the orthodox methods in current use are time-consuming and labour intensive.
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Devil's Claw—A review of the ethnobotany, phytochemistry and biological activity of Harpagophytum procumbens
Journal of Ethnopharmacology, 2012Co-Authors: Nontobeko Mncwangi, Weiyang Chen, Ilze Vermaak, Alvaro Viljoen, Nigel GerickeAbstract:ETHNOPHARMACOLOGICAL RELEVANCE: Harpagophytum procumbens subps. procumbens (Burch.) DC. ex Meisn. (Pedaliaceae) is an important traditional medicine growing in the Kalahari region of southern Africa where it is consumed as a general health tonic and for treating diverse ailments including arthritis, pain, fever, ulcers and boils. AIM OF THE REVIEW: To provide a comprehensive overview of the ethnobotany, phytochemistry and biological activity of H. procumbens and possibly make recommendations for further research. MATERIALS AND METHODS: Peer-reviewed articles on H. procumbens were acquired on Scopus, ScienceDirect and SciFinder, there was no specific timeline set for the search. A focus group discussion was held with different communities in Botswana to further understand ethnobotanical uses of the plant. RESULTS: Harpogophytum procumbens is used for a wide variety of health conditions in the form of infusions, decoctions, tinctures, powders and extracts. In addition to the common local use for arthritis and pain, other ethnomedicinal uses include dyspepsia, fever, blood diseases, urinary tract infections, postpartum pain, sprains, sores, ulcers and boils. Scientific studies revealed that H. procumbens exhibits analgesic, anti-oxidant, anti-diabetic, anti-epileptic, antimicrobial and antimalarial activities amongst others. Iridoid glycosides and phenylpropanoid glycosides have been the focus of phytochemical investigations as the biological activity has been ascribed to the iridoid glycosides (such as harpagoside and harpagide), which are common in nature and are known to possess anti-inflammatory activity. In addition, it has been shown that the hydrolysed products of harpagoside and harpagide have more pronounced anti-inflammatory activity when compared to the unhydrolysed compounds. Harpagophytum zeyheri is a close taxonomic ally of H. procumbens but H. procumbens is the favoured species of commerce, and contains higher levels of the pharmacologically active constituents. The two are used interchangeably and H. procumbens raw material is often intentionally adulterated with H. zeyheri and this may impact on the efficacy of inadequately controlled health products. The main exporter of this highly commercialised plant is Namibia. In 2009 alone, Harpagophytum exports were worth approximately €1.06 million. The high demand for health products based on this plant has led to over-harvesting, raising concerns about sustainability. Although only the secondary tubers are utilised commercially, the whole plant is often destroyed during harvesting. CONCLUSIONS: Harpagophytum procumbens is used to treat a wide range of ailments. Some of the ethnobotanical claims have been confirmed through in vitro studies, however, when the constituents deemed to be the biologically active compounds were isolated the efficacy was lower than that of the whole extract. This necessitates the use of a different approach where all the metabolites are considered using a robust method such as spectroscopy; the phytochemical data can then be superimposed on the biological activity. Furthermore, there is a need to develop rapid and efficient quality control methods for both raw materials and products because the orthodox methods in current use are time-consuming and labour intensive.
Alexander H Schmidt - One of the best experts on this subject based on the ideXlab platform.
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fast hplc for quality control of Harpagophytum procumbens by using a monolithic silica column method transfer from conventional particle based silica column
Journal of Chromatography A, 2005Co-Authors: Alexander H SchmidtAbstract:Abstract The applicability of a monolithic C18-bonded silica column for the rapid HPLC separation of ingredients in medicinal plants and their phytopharmaceutical preparations has been evaluated in the author's laboratory. In this presentation, an existing method for the determination of the iridoid glycoside harpagoside in Harpagophytum procumbens (Devil's Claw) was successfully transferred from a conventional particle-based C18 silica column to a monolithic silica column. The very high porosity of the stationary phase allows chromatography with a much lower backpressure than on conventional columns. Therefore, the flow rate could be easily increased from 0.8 mL/min (particle-based column) to 5 mL/min (monolithic column) and the run-time reduced from 30 to 5 min (that is a reduction about 85%!), without losing any chromatographic resolution of the compound of interest. The amount of harpagoside was measured with the original method on a conventional particle-based silica column and on the adapted method on a monolithic silica column. The statistical mean t-test showed no significant differences of the variances and the means indicating that the fast HPLC method is an acceptable alternative. The shorter analysis time makes the method very valuable for commercial quality control of Harpagophytum extracts and its pharmaceutical preparations.
Sigrun Chrubasik - One of the best experts on this subject based on the ideXlab platform.
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Micro-Morphometrical Assessment of the Effect of Harpagophytum procumbens Extract on Articular Cartilage in Rabbits with Experimental Osteoarthritis using Magnetic Resonance Imaging
Phytotherapy Research, 2011Co-Authors: L. Wachsmuth, E. Lindhorst, S. Wrubel, H. Hadzhiyski, Martin Hudelmaier, Felix Eckstein, Sigrun ChrubasikAbstract:In vitro effects indicate a putative beneficial effect of Harpagophytum procumbens on cartilage turnover, however, in vivo protective effects on cartilage have yet to be demonstrated. A 7.1T MRI scanner was used to derive measurements of thickness, surface area and volume of the tibial condylar cartilage and to assess their precision (in the case of volume also accuracy) against the volumes of dissected cartilage measured by water displacement. Quantitative measurements were made in 16 rabbits, 6 months after unilateral medial meniscectomy and transection of the anterior cruciate ligament, after which eight of these were given a proprietary extract of Harpagophytum procumbens (HP). A semiquantitative MRI-based grading of the tibial cartilage was also compared with a ‘macroscopic’ grading based on direct visual inspection of dissected joints. The test–retest precision for MRI-based measurement was ≤6.4%. MRI-based measurements correlated well with volumes of surgically resected cartilage (r = 0.97, pair-wise random difference 4.2%). The medial tibial cartilage thickness and volume were about 35% smaller in the operated knees than in the non-operated contralateral knees (p
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Systematic Review on the Safety of Harpagophytum Preparations for Osteoarthritic and Low Back Pain
Phytotherapy Research, 2008Co-Authors: Julia Vlachojannis, Basil D. Roufogalis, Sigrun ChrubasikAbstract:Harpagophytum products are a treatment option for osteoarthritic and low back pain. The aim of this study was to review the safety of treatment with Harpagophytum procumbens. The databases OVID(MEDLINE), PUBMED and COCHRANE COLLABORATION LIBRARY were searched back to 1985 for studies with Harpagophytum procumbens. Twenty-eight clinical trials were identified of which 20 stated adverse events. In none of the double-blind studies was the incidence of adverse events during treatment with Harpagophytum procumbens higher than during placebo treatment. Minor adverse events occurred in around 3% of the patients, mainly gastrointestinal adverse events. A few reports of acute toxicity were found but there were no reports on chronic toxicity. Since the dosage used in most of the studies is at the lower limit and since long-term treatment with Harpagophytum products is advisable, more safety data are urgently needed.
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Effectiveness of Harpagophytum Extracts and Clinical Efficacy
Phytotherapy Research, 2004Co-Authors: Sigrun Chrubasik, Christian Conradt, Basil D. RoufogalisAbstract:Various preparations from Harpagophytum procumbens are used for the treatment of pain in the joints and lower back. Studies published in peer reviewed journals were examined for their clinical evidence. The studies offering preparations with 50-60 mg harpagoside in the daily dosage are of better quality and provide more reliable evidence on efficacy than a proprietary ethanol extract with half the amount of harpagoside per day. However, confirmatory studies are required for all extracts before they can gain a place in treatment guidelines.
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The quality of clinical trials with Harpagophytum procumbens.
Phytomedicine, 2003Co-Authors: Sigrun Chrubasik, Christian Conradt, A. BlackAbstract:Summary Objective: To examine systematically the quality of the clinical trials investigating the effectiveness of Harpagophytum products. Methods: Literature searches and enquiries to experts identified 20 studies of treatment with various Harpagophytum products (powder, aqueous and ethanolic extracts) for exacerbations of chronic musculoskeletal pain. Eight were open uncontrolled observational studies, one comparing progress under treatment for pain in back, knee and hip pain. Two were open comparisons with conventional treatment, only one of which was randomised. Ten were double-blinded, randomised controlled comparisons, 8 with placebo and 2 with NSAID comparator treatments. Indices of the internal and external validities were examined by reference to a checklist to see how well the studies answered the questions: do Harpagophytum products work and do they work as well as more conventional comparator treatments? Results: The uncontrolled trials, though providing useful preliminary estimates of the possible effect of treating various conditions, could not separate the effects of the Harpagophytum product from whatever placebo effect might have been exerted in the circumstances of the study. The 2 open comparisons were open to performance, detection and/or selection bias. Of the 8 randomised double blinded controlled comparisons with placebo, 6 were marred by lack of transparency, one could not provide definitive evidence from its pre-selected principal outcome measure, and one provided qood quality evidence of a dose dependent superiority of effect over placebo, though this was with a product that is not generally available for clinical practice. One of the randomised controlled comparisons with comparator (Doloteffin® versus rofecoxib) was intended only as a pilot and studied too few patients for definitive conclusions whereas the other did provide good evidence that the powder, Harpadol® is not importantly less effective than the weak NSAID diacerhein. Conclusions: Evidence of effectiveness of Harpagophytum products is not transferrable from product to product. The results of some studies suggest some effectiveness for some products, but for none of the clinically available products is the quality of evidence totally satisfactory. It is better so far with products that contain at least 50 mg of harpagoside in the daily dosage than with products (which happen to be of ethanolic extraction) that contain less.
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Physicochemical properties of harpagoside and its in vitro release from Harpagophytum procumbens extract tablets.
Phytomedicine, 2000Co-Authors: Sigrun Chrubasik, Frank Sporer, R. Dillmann-marschner, A. Friedmann, Michael WinkAbstract:Summary The objective of this investigation was to characterize the active-component harpagoside of Harpagophytum extract from a physico-chemical perspective and to determine its in-vitro release from tablets according to DAB 1996. It was found that both pure harpagoside and harpagoside in Harpagophytum extract have an octanol-water distribution coefficient of approximately 4 which is neither dependent on temperature nor on pH. The mean harpagoside content in Harpagophytum tablets of Batch 9102 was 16.4 mg (S.D. 0.2; S.E. 0.03). Related to a tablet weight of 365 mg (100%), this corresponds to a haragoside content of 4.5% (S.D. 0.049; S.E. 0.006). On average the tablets disintegrate after 18 ± 3 minutes (mean ± SD). The tablets taken from Batch 9102 released the active component harpagoside well, with a t50 of 13.5 min, a t90 of 23 min and a t95 of 25 min in relation to 16.5 mg of harpagoside per dose. Harpagoside content decreased by about 10% in artificial gastric fluid within a period of 3 hours and remained stable in artificial intestinal fluid for a period of 6 hours.
