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Christopher A Gray - One of the best experts on this subject based on the ideXlab platform.
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Isolation of Phomopsolide A and 6(E)-Phomopsolide A as Antimycobacterial Natural Products from an Unidentified Endophyte of the Canadian Medicinal Plant Heracleum Maximum.
Natural product communications, 2015Co-Authors: Trevor N. Clark, Duncan Webster, John A Johnson, K Ellsworth, Stéphanie Jean, Gilles A. Robichaud, Christopher A GrayAbstract:An extract of an unidentified endophyte from the Canadian medicinal plant Heracleum Maximum exhibited a unique metabolomic profile and significant antimycobacterial activity against Mycobacterium tuberculosis H37Ra. Bioassay guided fractionation of the extract led to the isolation of phomopsolide A (1) and 6(E)-phomopsolide A (2). This is the first report of antimycobacterial activity for 1 and 2.
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The Canadian medicinal plant Heracleum Maximum contains antimycobacterial diynes and furanocoumarins.
Journal of ethnopharmacology, 2013Co-Authors: Taryn O׳neill, Duncan Webster, John A Johnson, Christopher A GrayAbstract:Abstract Ethnopharmacological relevance Heracleum Maximum is amongst the most commonly used plants by the indigenous peoples of North America. The First Nations of the eastern Canada use infusions of Heracleum Maximum roots for the treatment of respiratory ailments including tuberculosis. Previous investigations of extracts derived from the roots of Heracleum Maximum have shown it to possess antimycobacterial activity. Aim of the study: To isolate and identify antimycobacterial constituents from the roots of Heracleum Maximum. Materials and methods A methanolic extract of Heracleum Maximum roots was subjected to bioassay guided fractionation using the microplate resazurin assay (MRA) to assess inhibitory activity against Mycobacterium tuberculosis strain H37Ra. The antimycobacterial constituents were identified by NMR, MS and polarimetry. Results The polyacetylene (3R,8S)-falcarindiol and the furanocoumarins bergapten, isobergapten, angelicin, sphondin, pimpinellin, isopimpinellin and 6-isopentenyloxyisobergapten were isolated from the Heracleum Maximum root extract. (3R,8S)-Falcarindiol and 6-isopentenyloxyisobergapten exhibited MICs of 24 μM and 167 μM and IC50s of 6 μM and 27 μM against Mycobacterium tuberculosis H37Ra respectively. The remaining furanocoumarins bergapten, isobergapten, angelicin, sphondin, pimpinellin, and isopimpinellin were less active, with MICs of 925, 1850, 2149, 1859, 812 and 1625 μM and IC50s of 125, 344, 350, 351, 389 and 406 μM. Conclusions (3R,8S)-Falcarindiol, bergapten, isobergapten, angelicin, sphondin, pimpinellin, isopimpinellin and 6-isopentenyloxyisobergapten were identified as the principal constituents responsible for the antimycobacterial activity of the roots of Heracleum Maximum. This work supports the ethnopharmacological use of Heracleum Maximum by Canadian First Nations and Native American communities as a treatment for infectious diseases, specifically tuberculosis.
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antimycobacterial screening of traditional medicinal plants using the microplate resazurin assay
Canadian Journal of Microbiology, 2010Co-Authors: Duncan Webster, Jill Moorej Moore, Tracy Manningt Manning, Dennis Kunimotod Kunimoto, Darren Leblancd Leblanc, John A Johnson, Christopher A GrayAbstract:Multidrug-resistant Mycobacterium tuberculosis strains have rapidly become a global health concern. North American First Nations communities have used traditional medicines for generations to treat many pulmonary infections. In this study, we evaluated the antimycobacterial activity of 5 medicinal plants traditionally used as general therapeutics for pulmonary illnesses and specifically as treatments for tuberculosis. Aqueous extracts of Aralia nudicaulis, Symplocarpus foetidus, Heracleum Maximum, Juniperus communis, and Acorus calamus were screened for antimycobacterial activity against Bacillus Calmette–Guerin, Mycobacterium avium, and M. tuberculosis H37Ra using the colorimetric microplate resazurin assay. Extracts of Acorus calamus and H. Maximum root demonstrated significant antimycobacterial activity comparable to that of the rifampin control (2 µg/mL). Evaluation of the cytotoxicity of these 2 extracts using the MTT assay also showed that the extracts were less toxic to 3 human cell lines than was ...
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Antimycobacterial screening of traditional medicinal plants using the microplate resazurin assay
Canadian journal of microbiology, 2010Co-Authors: Duncan Webster, Jill Moorej Moore, Tracy Manningt Manning, Dennis Kunimotod Kunimoto, Darren Leblancd Leblanc, John A Johnson, Timothy D.g. Lee, Christopher A GrayAbstract:Multidrug-resistant Mycobacterium tuberculosis strains have rapidly become a global health concern. North American First Nations communities have used traditional medicines for generations to treat many pulmonary infections. In this study, we evaluated the antimycobacterial activity of 5 medicinal plants traditionally used as general therapeutics for pulmonary illnesses and specifically as treatments for tuberculosis. Aqueous extracts of Aralia nudicaulis, Symplocarpus foetidus, Heracleum Maximum, Juniperus communis, and Acorus calamus were screened for antimycobacterial activity against Bacillus Calmette-Guerin, Mycobacterium avium, and M. tuberculosis H37Ra using the colorimetric microplate resazurin assay. Extracts of Acorus calamus and H. Maximum root demonstrated significant antimycobacterial activity comparable to that of the rifampin control (2 microg/mL). Evaluation of the cytotoxicity of these 2 extracts using the MTT assay also showed that the extracts were less toxic to 3 human cell lines than was the DMSO positive control. This study demonstrates that aqueous extracts of the roots of H. Maximum and Acorus calamus possess strong in vitro antimycobacterial activity, validates traditional knowledge, and provides potential for the development of urgently needed novel antituberculous therapeutics.
Duncan Webster - One of the best experts on this subject based on the ideXlab platform.
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Isolation of Phomopsolide A and 6(E)-Phomopsolide A as Antimycobacterial Natural Products from an Unidentified Endophyte of the Canadian Medicinal Plant Heracleum Maximum.
Natural product communications, 2015Co-Authors: Trevor N. Clark, Duncan Webster, John A Johnson, K Ellsworth, Stéphanie Jean, Gilles A. Robichaud, Christopher A GrayAbstract:An extract of an unidentified endophyte from the Canadian medicinal plant Heracleum Maximum exhibited a unique metabolomic profile and significant antimycobacterial activity against Mycobacterium tuberculosis H37Ra. Bioassay guided fractionation of the extract led to the isolation of phomopsolide A (1) and 6(E)-phomopsolide A (2). This is the first report of antimycobacterial activity for 1 and 2.
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The Canadian medicinal plant Heracleum Maximum contains antimycobacterial diynes and furanocoumarins.
Journal of ethnopharmacology, 2013Co-Authors: Taryn O׳neill, Duncan Webster, John A Johnson, Christopher A GrayAbstract:Abstract Ethnopharmacological relevance Heracleum Maximum is amongst the most commonly used plants by the indigenous peoples of North America. The First Nations of the eastern Canada use infusions of Heracleum Maximum roots for the treatment of respiratory ailments including tuberculosis. Previous investigations of extracts derived from the roots of Heracleum Maximum have shown it to possess antimycobacterial activity. Aim of the study: To isolate and identify antimycobacterial constituents from the roots of Heracleum Maximum. Materials and methods A methanolic extract of Heracleum Maximum roots was subjected to bioassay guided fractionation using the microplate resazurin assay (MRA) to assess inhibitory activity against Mycobacterium tuberculosis strain H37Ra. The antimycobacterial constituents were identified by NMR, MS and polarimetry. Results The polyacetylene (3R,8S)-falcarindiol and the furanocoumarins bergapten, isobergapten, angelicin, sphondin, pimpinellin, isopimpinellin and 6-isopentenyloxyisobergapten were isolated from the Heracleum Maximum root extract. (3R,8S)-Falcarindiol and 6-isopentenyloxyisobergapten exhibited MICs of 24 μM and 167 μM and IC50s of 6 μM and 27 μM against Mycobacterium tuberculosis H37Ra respectively. The remaining furanocoumarins bergapten, isobergapten, angelicin, sphondin, pimpinellin, and isopimpinellin were less active, with MICs of 925, 1850, 2149, 1859, 812 and 1625 μM and IC50s of 125, 344, 350, 351, 389 and 406 μM. Conclusions (3R,8S)-Falcarindiol, bergapten, isobergapten, angelicin, sphondin, pimpinellin, isopimpinellin and 6-isopentenyloxyisobergapten were identified as the principal constituents responsible for the antimycobacterial activity of the roots of Heracleum Maximum. This work supports the ethnopharmacological use of Heracleum Maximum by Canadian First Nations and Native American communities as a treatment for infectious diseases, specifically tuberculosis.
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antimycobacterial screening of traditional medicinal plants using the microplate resazurin assay
Canadian Journal of Microbiology, 2010Co-Authors: Duncan Webster, Jill Moorej Moore, Tracy Manningt Manning, Dennis Kunimotod Kunimoto, Darren Leblancd Leblanc, John A Johnson, Christopher A GrayAbstract:Multidrug-resistant Mycobacterium tuberculosis strains have rapidly become a global health concern. North American First Nations communities have used traditional medicines for generations to treat many pulmonary infections. In this study, we evaluated the antimycobacterial activity of 5 medicinal plants traditionally used as general therapeutics for pulmonary illnesses and specifically as treatments for tuberculosis. Aqueous extracts of Aralia nudicaulis, Symplocarpus foetidus, Heracleum Maximum, Juniperus communis, and Acorus calamus were screened for antimycobacterial activity against Bacillus Calmette–Guerin, Mycobacterium avium, and M. tuberculosis H37Ra using the colorimetric microplate resazurin assay. Extracts of Acorus calamus and H. Maximum root demonstrated significant antimycobacterial activity comparable to that of the rifampin control (2 µg/mL). Evaluation of the cytotoxicity of these 2 extracts using the MTT assay also showed that the extracts were less toxic to 3 human cell lines than was ...
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Antimycobacterial screening of traditional medicinal plants using the microplate resazurin assay
Canadian journal of microbiology, 2010Co-Authors: Duncan Webster, Jill Moorej Moore, Tracy Manningt Manning, Dennis Kunimotod Kunimoto, Darren Leblancd Leblanc, John A Johnson, Timothy D.g. Lee, Christopher A GrayAbstract:Multidrug-resistant Mycobacterium tuberculosis strains have rapidly become a global health concern. North American First Nations communities have used traditional medicines for generations to treat many pulmonary infections. In this study, we evaluated the antimycobacterial activity of 5 medicinal plants traditionally used as general therapeutics for pulmonary illnesses and specifically as treatments for tuberculosis. Aqueous extracts of Aralia nudicaulis, Symplocarpus foetidus, Heracleum Maximum, Juniperus communis, and Acorus calamus were screened for antimycobacterial activity against Bacillus Calmette-Guerin, Mycobacterium avium, and M. tuberculosis H37Ra using the colorimetric microplate resazurin assay. Extracts of Acorus calamus and H. Maximum root demonstrated significant antimycobacterial activity comparable to that of the rifampin control (2 microg/mL). Evaluation of the cytotoxicity of these 2 extracts using the MTT assay also showed that the extracts were less toxic to 3 human cell lines than was the DMSO positive control. This study demonstrates that aqueous extracts of the roots of H. Maximum and Acorus calamus possess strong in vitro antimycobacterial activity, validates traditional knowledge, and provides potential for the development of urgently needed novel antituberculous therapeutics.
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Immunostimulant properties of Heracleum Maximum Bartr.
Journal of ethnopharmacology, 2006Co-Authors: Duncan Webster, Timothy D.g. Lee, Pierre Taschereau, Tannis JurgensAbstract:The root of Heracleum Maximum Bartr. (Umbelliferae), known to possess direct antifungal and anti-mycobacterial properties, has been reported anecdotally to possess antiviral properties. It was therefore hypothesized that the plant may have immunostimulant properties. This hypothesis was tested using a macrophage activation assay to evaluate the ability of aqueous extracts of the root of Heracleum Maximum to stimulate IL-6 production. All Heracleum Maximum extracts were found to stimulate IL-6 and produced a steep dose-response curve. With the assay performed twice in the absence of the macrophage primer, IFN-gamma, the mean IL-6 production in the setting of the strongest extract was 3648pg/ml (95% CI 3361-3935) and 5430pg/ml (95% CI 4976-5885) as compared to 2722pg/ml (95% CI 2620-2824) and 6772pg/ml (95% CI 6282-7262) produced by the LPS positive control, respectively. In the presence of IFN-gamma, the strongest extract produced a mean concentration of IL-6 of 21804pg/ml (95% CI 19755-23854) surpassing the 14893pg/ml (13159-16628) produced by the LPS+IFN-gamma positive control. These positive results confirm the hypothesis of immunostimulation and thus support the anecdotal reports of antiviral activity.
John A Johnson - One of the best experts on this subject based on the ideXlab platform.
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Isolation of Phomopsolide A and 6(E)-Phomopsolide A as Antimycobacterial Natural Products from an Unidentified Endophyte of the Canadian Medicinal Plant Heracleum Maximum.
Natural product communications, 2015Co-Authors: Trevor N. Clark, Duncan Webster, John A Johnson, K Ellsworth, Stéphanie Jean, Gilles A. Robichaud, Christopher A GrayAbstract:An extract of an unidentified endophyte from the Canadian medicinal plant Heracleum Maximum exhibited a unique metabolomic profile and significant antimycobacterial activity against Mycobacterium tuberculosis H37Ra. Bioassay guided fractionation of the extract led to the isolation of phomopsolide A (1) and 6(E)-phomopsolide A (2). This is the first report of antimycobacterial activity for 1 and 2.
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The Canadian medicinal plant Heracleum Maximum contains antimycobacterial diynes and furanocoumarins.
Journal of ethnopharmacology, 2013Co-Authors: Taryn O׳neill, Duncan Webster, John A Johnson, Christopher A GrayAbstract:Abstract Ethnopharmacological relevance Heracleum Maximum is amongst the most commonly used plants by the indigenous peoples of North America. The First Nations of the eastern Canada use infusions of Heracleum Maximum roots for the treatment of respiratory ailments including tuberculosis. Previous investigations of extracts derived from the roots of Heracleum Maximum have shown it to possess antimycobacterial activity. Aim of the study: To isolate and identify antimycobacterial constituents from the roots of Heracleum Maximum. Materials and methods A methanolic extract of Heracleum Maximum roots was subjected to bioassay guided fractionation using the microplate resazurin assay (MRA) to assess inhibitory activity against Mycobacterium tuberculosis strain H37Ra. The antimycobacterial constituents were identified by NMR, MS and polarimetry. Results The polyacetylene (3R,8S)-falcarindiol and the furanocoumarins bergapten, isobergapten, angelicin, sphondin, pimpinellin, isopimpinellin and 6-isopentenyloxyisobergapten were isolated from the Heracleum Maximum root extract. (3R,8S)-Falcarindiol and 6-isopentenyloxyisobergapten exhibited MICs of 24 μM and 167 μM and IC50s of 6 μM and 27 μM against Mycobacterium tuberculosis H37Ra respectively. The remaining furanocoumarins bergapten, isobergapten, angelicin, sphondin, pimpinellin, and isopimpinellin were less active, with MICs of 925, 1850, 2149, 1859, 812 and 1625 μM and IC50s of 125, 344, 350, 351, 389 and 406 μM. Conclusions (3R,8S)-Falcarindiol, bergapten, isobergapten, angelicin, sphondin, pimpinellin, isopimpinellin and 6-isopentenyloxyisobergapten were identified as the principal constituents responsible for the antimycobacterial activity of the roots of Heracleum Maximum. This work supports the ethnopharmacological use of Heracleum Maximum by Canadian First Nations and Native American communities as a treatment for infectious diseases, specifically tuberculosis.
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antimycobacterial screening of traditional medicinal plants using the microplate resazurin assay
Canadian Journal of Microbiology, 2010Co-Authors: Duncan Webster, Jill Moorej Moore, Tracy Manningt Manning, Dennis Kunimotod Kunimoto, Darren Leblancd Leblanc, John A Johnson, Christopher A GrayAbstract:Multidrug-resistant Mycobacterium tuberculosis strains have rapidly become a global health concern. North American First Nations communities have used traditional medicines for generations to treat many pulmonary infections. In this study, we evaluated the antimycobacterial activity of 5 medicinal plants traditionally used as general therapeutics for pulmonary illnesses and specifically as treatments for tuberculosis. Aqueous extracts of Aralia nudicaulis, Symplocarpus foetidus, Heracleum Maximum, Juniperus communis, and Acorus calamus were screened for antimycobacterial activity against Bacillus Calmette–Guerin, Mycobacterium avium, and M. tuberculosis H37Ra using the colorimetric microplate resazurin assay. Extracts of Acorus calamus and H. Maximum root demonstrated significant antimycobacterial activity comparable to that of the rifampin control (2 µg/mL). Evaluation of the cytotoxicity of these 2 extracts using the MTT assay also showed that the extracts were less toxic to 3 human cell lines than was ...
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Antimycobacterial screening of traditional medicinal plants using the microplate resazurin assay
Canadian journal of microbiology, 2010Co-Authors: Duncan Webster, Jill Moorej Moore, Tracy Manningt Manning, Dennis Kunimotod Kunimoto, Darren Leblancd Leblanc, John A Johnson, Timothy D.g. Lee, Christopher A GrayAbstract:Multidrug-resistant Mycobacterium tuberculosis strains have rapidly become a global health concern. North American First Nations communities have used traditional medicines for generations to treat many pulmonary infections. In this study, we evaluated the antimycobacterial activity of 5 medicinal plants traditionally used as general therapeutics for pulmonary illnesses and specifically as treatments for tuberculosis. Aqueous extracts of Aralia nudicaulis, Symplocarpus foetidus, Heracleum Maximum, Juniperus communis, and Acorus calamus were screened for antimycobacterial activity against Bacillus Calmette-Guerin, Mycobacterium avium, and M. tuberculosis H37Ra using the colorimetric microplate resazurin assay. Extracts of Acorus calamus and H. Maximum root demonstrated significant antimycobacterial activity comparable to that of the rifampin control (2 microg/mL). Evaluation of the cytotoxicity of these 2 extracts using the MTT assay also showed that the extracts were less toxic to 3 human cell lines than was the DMSO positive control. This study demonstrates that aqueous extracts of the roots of H. Maximum and Acorus calamus possess strong in vitro antimycobacterial activity, validates traditional knowledge, and provides potential for the development of urgently needed novel antituberculous therapeutics.
J Santos - One of the best experts on this subject based on the ideXlab platform.
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Phytochemical analysis and extraction/isolation and characterization of a new furanocoumarin from Heracleum Maximum
Planta Medica, 2014Co-Authors: P Dhar, I Heckler, A Garcia, J SantosAbstract:Furanocoumarins are a class of naturally occurring compounds found in many plants and contain a furan ring fused with a coumarin (benzo-α-pyrone) either in a linear or angular fashion leading to Psoralen or Angelicin types of furanocoumarins. Heracleum Maximum, a plant native to North America is known to contain several furanocoumarins. This plant has been used in traditional medicine by Native Americans to prevent and treat several ailments like tuberculosis, influenza, cholera and small pox. Prior research from our lab has shown that Heracleum Maximum ethanolic seed extract is toxic to brine shrimp.The objective of this study was to do a phytochemical analysis of the Heracleum seed extract and identify the toxic compound(s).The powdered seeds were extracted with hexane and water separately, using continuous extraction and the aqueous extract was lyophilized to give a solid whereas the hexane extract was concentrated to yield a green liquid (with some solid separating out). The solid (hexane extract) was filtered and recrystallized with hexane/ether. Preparative TLC on the solid obtained from the hexane extract led to the isolation of a previously unreported furanocoumarin from this species called Heratomin, which was characterized by NMR. Phytochemical analysis of the aqueous and hexane extract and extraction/isolation and characterization of the new compound from this plant will be discussed.
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phytochemical analysis and extraction isolation and characterization of a new furanocoumarin from Heracleum Maximum
Planta Medica, 2014Co-Authors: P Dhar, I Heckler, A Garcia, J SantosAbstract:Furanocoumarins are a class of naturally occurring compounds found in many plants and contain a furan ring fused with a coumarin (benzo-α-pyrone) either in a linear or angular fashion leading to Psoralen or Angelicin types of furanocoumarins. Heracleum Maximum, a plant native to North America is known to contain several furanocoumarins. This plant has been used in traditional medicine by Native Americans to prevent and treat several ailments like tuberculosis, influenza, cholera and small pox. Prior research from our lab has shown that Heracleum Maximum ethanolic seed extract is toxic to brine shrimp.The objective of this study was to do a phytochemical analysis of the Heracleum seed extract and identify the toxic compound(s).The powdered seeds were extracted with hexane and water separately, using continuous extraction and the aqueous extract was lyophilized to give a solid whereas the hexane extract was concentrated to yield a green liquid (with some solid separating out). The solid (hexane extract) was filtered and recrystallized with hexane/ether. Preparative TLC on the solid obtained from the hexane extract led to the isolation of a previously unreported furanocoumarin from this species called Heratomin, which was characterized by NMR. Phytochemical analysis of the aqueous and hexane extract and extraction/isolation and characterization of the new compound from this plant will be discussed.
P Dhar - One of the best experts on this subject based on the ideXlab platform.
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Phytochemical analysis and extraction/isolation and characterization of a new furanocoumarin from Heracleum Maximum
Planta Medica, 2014Co-Authors: P Dhar, I Heckler, A Garcia, J SantosAbstract:Furanocoumarins are a class of naturally occurring compounds found in many plants and contain a furan ring fused with a coumarin (benzo-α-pyrone) either in a linear or angular fashion leading to Psoralen or Angelicin types of furanocoumarins. Heracleum Maximum, a plant native to North America is known to contain several furanocoumarins. This plant has been used in traditional medicine by Native Americans to prevent and treat several ailments like tuberculosis, influenza, cholera and small pox. Prior research from our lab has shown that Heracleum Maximum ethanolic seed extract is toxic to brine shrimp.The objective of this study was to do a phytochemical analysis of the Heracleum seed extract and identify the toxic compound(s).The powdered seeds were extracted with hexane and water separately, using continuous extraction and the aqueous extract was lyophilized to give a solid whereas the hexane extract was concentrated to yield a green liquid (with some solid separating out). The solid (hexane extract) was filtered and recrystallized with hexane/ether. Preparative TLC on the solid obtained from the hexane extract led to the isolation of a previously unreported furanocoumarin from this species called Heratomin, which was characterized by NMR. Phytochemical analysis of the aqueous and hexane extract and extraction/isolation and characterization of the new compound from this plant will be discussed.
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phytochemical analysis and extraction isolation and characterization of a new furanocoumarin from Heracleum Maximum
Planta Medica, 2014Co-Authors: P Dhar, I Heckler, A Garcia, J SantosAbstract:Furanocoumarins are a class of naturally occurring compounds found in many plants and contain a furan ring fused with a coumarin (benzo-α-pyrone) either in a linear or angular fashion leading to Psoralen or Angelicin types of furanocoumarins. Heracleum Maximum, a plant native to North America is known to contain several furanocoumarins. This plant has been used in traditional medicine by Native Americans to prevent and treat several ailments like tuberculosis, influenza, cholera and small pox. Prior research from our lab has shown that Heracleum Maximum ethanolic seed extract is toxic to brine shrimp.The objective of this study was to do a phytochemical analysis of the Heracleum seed extract and identify the toxic compound(s).The powdered seeds were extracted with hexane and water separately, using continuous extraction and the aqueous extract was lyophilized to give a solid whereas the hexane extract was concentrated to yield a green liquid (with some solid separating out). The solid (hexane extract) was filtered and recrystallized with hexane/ether. Preparative TLC on the solid obtained from the hexane extract led to the isolation of a previously unreported furanocoumarin from this species called Heratomin, which was characterized by NMR. Phytochemical analysis of the aqueous and hexane extract and extraction/isolation and characterization of the new compound from this plant will be discussed.