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Ikhlas A. Khan - One of the best experts on this subject based on the ideXlab platform.
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14β hydroxypregnanes from succulent plants belonging to Hoodia gordonii and caralluma genus extraction biological activities and synthesis
Studies in natural products chemistry, 2013Co-Authors: Yatin J Shukla, Philippe Geoffroy, Ikhlas A. Khan, Michel MieschAbstract:Abstract Caralluma and Hoodia are genera of succulent plants belonging to the subfamily of Asclepiadoideae in the family of Apocynaceae. Caralluma is distributed in dry regions of tropical Asia and Africa, majority of species being indigenous to the Indian subcontinent and the Arabian Peninsula. The genus Hoodia is mainly found in the Kalahari desert regions in Southern Africa. We focus on Caralluma adscendens var. fimbriata and Hoodia gordonii due to their popularity and growing commercial interest during the past 20 years. Indeed, it was claimed that these succulent plants contain bioactive compounds, especially 14β-hydroxypregnane derivatives, which showed appetite-suppressant activity and weight loss properties. This chapter describes the isolation, biological properties, and synthesis of 14β-hydroxypregnane derivatives found in C. adscendens var. fimbriata and H. gordonii .
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bioavailability pharmacokinetics and tissue distribution of the oxypregnane steroidal glycoside p57as3 p57 from Hoodia gordonii in mouse model
Planta Medica, 2010Co-Authors: Vamsi L. M. Madgula, Mohammad K. Ashfaq, Bharathi Avula, Yan-hong Wang, Ikhlas A. Khan, Larry A. Walker, Shabana I. KhanAbstract:: P57AS3 (P57), an oxypregnane steroidal glycoside, is known to be responsible for the appetite suppressing activity of Hoodia GORDONII, a dietary supplement used for weight loss. In this study, bioavailability, pharmacokinetics, and tissue distribution of P57 were determined in CD1 female mice after administration of a single dose of enriched methanolic extract of Hoodia GORDONII (equivalent to a dose of 25 mg of P57/kg) by oral gavage or a single dose of purified P57 (25 mg/kg) intravenously. The level of P57 in plasma and tissues (brain, liver, kidney, and intestine) was determined by UPLC-MS. After oral administration of Hoodia extract, the peak plasma level of P57 was achieved in 0.6 h. Upon intravenous administration, the plasma clearance rate of P57 was 1.09 L/h/kg. P57 was rapidly distributed and eliminated from the tissues within 4 hours. The level of tissue distribution was highest in the kidney followed by liver and brain. Upon oral administration, P57 was not detected in the brain and a very low concentration was seen in the intestine, kidney, and liver. Tissue/plasma ratio was 0.33 for brain, 0.57 for liver, and 0.75 for kidney with IV route and 0.11 for intestine, 0.02 for liver, and 0.04 for kidney with oral route. The half-life of the elimination phase was similar with both routes. The oral bioavailability was 47.5 % and the half-life of the absorption phase was 0.13 h. In conclusion, P57 showed moderate bioavailability and was eliminated rapidly.
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characterization of in vitro pharmacokinetic properties of hoodigogenin a from Hoodia gordonii
Planta Medica, 2010Co-Authors: Vamsi L. M. Madgula, Yatin J Shukla, Rahul S. Pawar, Bharathi Avula, Ikhlas A. Khan, Larry A. Walker, Shabana I. KhanAbstract:: This study was aimed to predict the pharmacokinetic properties of hoodigogenin A, which is the aglycone of the oxypregnane steroidal glycoside P57AS3 (P57) isolated from Hoodia gordonii. A series of in vitro assays was used to predict its gastric, intestinal and metabolic stability, intestinal and blood brain barrier (BBB) transport, protein binding and interaction with major drug metabolising enzymes. In the simulated gastric fluid, hoodigogenin A was stable (2 % degradation in 60 minutes) whereas P57 was unstable (45 % degradation in 30 minutes). In simulated intestinal fluid, P57 was degraded to an extent of 8 % in 180 minutes, while hoodigogenin A was stable. Hoodigogenin A was efficiently transported by passive diffusion across Caco-2 and MDR1-MDCK monolayers with P(app) values in the range of 32 x 10(-6) cm/sec and 22 x 10(-6) cm/sec, respectively. The compound was metabolically unstable in human liver microsomes and S9 fractions with a CL' (int) of 71 and 120 mL/min/kg, respectively and was bound to the plasma proteins to an extent of 92 %. The compound strongly inhibited CYP3A4 activity (IC(50) 3 microM), indicating a possibility of drug-herb/botanical interactions when products containing H. gordonii are used simultaneously with other botanicals/herbs/drugs.
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identification and differentiation between Hoodia gordonii masson sweet ex decne opuntia ficus indica l p miller and related Hoodia species using microscopy and pcr
Journal of Herbs Spices & Medicinal Plants, 2009Co-Authors: Vaishali C. Joshi, Natascha Techen, Brian E Scheffler, Ikhlas A. KhanAbstract:Hoodia gordonii, an appetite suppressant, is used extensively as a botanical dietary supplement. Microscopy and molecular genetic procedures are provided for identification and differentiation between H. gordonii, Opuntia ficus indica, and other related Hoodia species.
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pregnane glycosides from Hoodia gordonii
Phytochemistry, 2009Co-Authors: Yatin J Shukla, Yuanqing Ding, Rahul S. Pawar, Xingcong Li, Daneel Ferreira, Ikhlas A. KhanAbstract:Abstract Hoodia gordonii is a ‘weight loss’ herb, which has gained popularity in the western countries as an appetite suppressant dietary supplement. Phytochemical study of its aerial parts led to isolation of seven pregnane glycosides (hoodigosides W–Z, hoodistanalosides A–B). Their structures were elucidated by chemical degradation studies and spectroscopic methods, including 1D and 2D NMR and CD spectroscopic methods.
Bharathi Avula - One of the best experts on this subject based on the ideXlab platform.
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bioavailability pharmacokinetics and tissue distribution of the oxypregnane steroidal glycoside p57as3 p57 from Hoodia gordonii in mouse model
Planta Medica, 2010Co-Authors: Vamsi L. M. Madgula, Mohammad K. Ashfaq, Bharathi Avula, Yan-hong Wang, Ikhlas A. Khan, Larry A. Walker, Shabana I. KhanAbstract:: P57AS3 (P57), an oxypregnane steroidal glycoside, is known to be responsible for the appetite suppressing activity of Hoodia GORDONII, a dietary supplement used for weight loss. In this study, bioavailability, pharmacokinetics, and tissue distribution of P57 were determined in CD1 female mice after administration of a single dose of enriched methanolic extract of Hoodia GORDONII (equivalent to a dose of 25 mg of P57/kg) by oral gavage or a single dose of purified P57 (25 mg/kg) intravenously. The level of P57 in plasma and tissues (brain, liver, kidney, and intestine) was determined by UPLC-MS. After oral administration of Hoodia extract, the peak plasma level of P57 was achieved in 0.6 h. Upon intravenous administration, the plasma clearance rate of P57 was 1.09 L/h/kg. P57 was rapidly distributed and eliminated from the tissues within 4 hours. The level of tissue distribution was highest in the kidney followed by liver and brain. Upon oral administration, P57 was not detected in the brain and a very low concentration was seen in the intestine, kidney, and liver. Tissue/plasma ratio was 0.33 for brain, 0.57 for liver, and 0.75 for kidney with IV route and 0.11 for intestine, 0.02 for liver, and 0.04 for kidney with oral route. The half-life of the elimination phase was similar with both routes. The oral bioavailability was 47.5 % and the half-life of the absorption phase was 0.13 h. In conclusion, P57 showed moderate bioavailability and was eliminated rapidly.
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characterization of in vitro pharmacokinetic properties of hoodigogenin a from Hoodia gordonii
Planta Medica, 2010Co-Authors: Vamsi L. M. Madgula, Yatin J Shukla, Rahul S. Pawar, Bharathi Avula, Ikhlas A. Khan, Larry A. Walker, Shabana I. KhanAbstract:: This study was aimed to predict the pharmacokinetic properties of hoodigogenin A, which is the aglycone of the oxypregnane steroidal glycoside P57AS3 (P57) isolated from Hoodia gordonii. A series of in vitro assays was used to predict its gastric, intestinal and metabolic stability, intestinal and blood brain barrier (BBB) transport, protein binding and interaction with major drug metabolising enzymes. In the simulated gastric fluid, hoodigogenin A was stable (2 % degradation in 60 minutes) whereas P57 was unstable (45 % degradation in 30 minutes). In simulated intestinal fluid, P57 was degraded to an extent of 8 % in 180 minutes, while hoodigogenin A was stable. Hoodigogenin A was efficiently transported by passive diffusion across Caco-2 and MDR1-MDCK monolayers with P(app) values in the range of 32 x 10(-6) cm/sec and 22 x 10(-6) cm/sec, respectively. The compound was metabolically unstable in human liver microsomes and S9 fractions with a CL' (int) of 71 and 120 mL/min/kg, respectively and was bound to the plasma proteins to an extent of 92 %. The compound strongly inhibited CYP3A4 activity (IC(50) 3 microM), indicating a possibility of drug-herb/botanical interactions when products containing H. gordonii are used simultaneously with other botanicals/herbs/drugs.
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a rapid method for chemical fingerprint analysis of Hoodia species related genera and dietary supplements using uplc uv ms
Journal of Pharmaceutical and Biomedical Analysis, 2008Co-Authors: Bharathi Avula, Yatin J Shukla, Rahul S. Pawar, Troy J. Smillie, Yan-hong Wang, Ikhlas A. KhanAbstract:Abstract Recently, ultra-performance liquid chromatography (UPLC) has proven to be one of the most promising developments in the area of high-speed chromatographic separations with increased sensitivity and resolution. In this work, a reverse phase chromatographic method was developed using UPLC for the chemical fingerprint analysis of 12 hoodigosides, related genera and dietary supplements. The method is also used for the quantification of P57 in Hoodia species and dietary supplements that claim to contain Hoodia . The analysis was performed on a Waters Acquity UPLC system with an Acquity UPLC BEH C18 column (100 mm × 2.1 mm I.D., 1.7 μm) and a gradient elution of water and acetonitrile, both containing 0.05% formic acid with a run time of 15 min. The calibration curve of P57 showed good linearity ( r 2 > 0.999) within the established range (1–100 μg/mL). The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.3 and 0.9 μg/mL, respectively. The RSD for intra- and inter-day were less than 3.0%, and the recovery efficiency as 97–103%. LC–mass spectrometry coupled with electrospray ionization (ESI) interface method is described for the identification of P57. The developed method was successfully applied to the identification of 12 oxypregnane glycosides in four different species of Hoodia , 23 related genera and 35 dietary supplements that claim to contain H . gordonii . The UPLC profiles of various plant samples were compared for the presence of oxypregnane glycosides. Different sample matrices were successfully analyzed, providing the wide range of applicability of this method, including gels, capsules, tablets, sprays, tea bags, snack bars, powders and juices.
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identification and structural characterization of steroidal glycosides in Hoodia gordonii by ion trap tandem mass spectrometry and liquid chromatography coupled with electrospray ionization time of flight mass spectrometry
Rapid Communications in Mass Spectrometry, 2008Co-Authors: Bharathi Avula, Yatin J Shukla, Rahul S. Pawar, Troy J. Smillie, Yan-hong Wang, Ikhlas A. KhanAbstract:Electrospray ion-trap tandem mass spectrometry (ESI-MS/MS) and high-performance liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry (LC/ESI-TOFMS) were used to identify and characterize eight C-21 steroidal glycosides in Hoodia gordonii. A generalized fragmentation pathway was proposed by comparing the spectra acquired for eight C-21 steroidal glycosides. The steroidal glycosides in Hoodia gordonii have been classified into two major core groups: hoodigenin A and calogenin. Using the ESI-TOF method, the major core peak ions generated by hoodigenin A glycosides are m/z 313 and 295 and by calogenin glycosides are m/z 479, 461, 299 and 281, respectively. In the MS/MS spectra, fragmentation reactions of the [M+Na]+ ion were recorded to provide structural information about the glycosyl and aglycone moieties. The data illustrates the ability of positive mode ESI for the identification of hoodigenin A and calogenin glycosides, including the nature of the hoodigenin A and calogenin core, the number of sugar residues and the type of saccharide moiety. Copyright © 2008 John Wiley & Sons, Ltd.
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in vitro metabolic stability and intestinal transport of p57as3 p57 from Hoodia gordonii and its interaction with drug metabolizing enzymes
Planta Medica, 2008Co-Authors: Vamsi L. M. Madgula, Yatin J Shukla, Rahul S. Pawar, Bharathi Avula, Ikhlas A. Khan, Larry A. Walker, Shabana I. KhanAbstract:Hoodia GORDONII, a succulent cactus-like plant growing in South Africa, has been used in traditional medicine for its appetite suppressant properties. Its use as a dietary supplement to promote weight loss has recently gained popularity. An oxypregnane steroidal glycoside P57AS3 (P57) is reported to be the active constituent of the sap extract responsible for anorexigenic activity. No information is available about its metabolic stability, intestinal transport and interaction with drug metabolizing enzymes. In the present investigation, the metabolic stability of P57 in human liver microsomes and its interaction with drug metabolizing enzymes (CYP1A2, 2C9, 3A4 and 2D6) were determined. Intestinal transport of P57 was studied in the Caco-2 cell model of intestinal transport and absorption. P57 was metabolically stable in the presence of human liver microsomes. The compound inhibited CYP3A4 activity with an IC 50 value of 45 μM, whereas the activity of CYP 1A2, 2C9 and 2D6 was not inhibited. In the Caco-2 model, P57 exhibited a higher transport in the secretory direction than in the absorptive direction with efflux ratios of 3.1 and 3.8 at 100 and 200 μM, respectively. The efflux was inhibited by selective inhibitors of multidrug resistance associated proteins MRP1/MRP2 (MK-571) and P-gp (verapamil). In conclusion, intestinal transport of P57 was mediated by P-gp and MRP transporters. The compound was metabolically stable and showed weak inhibition of CYP 3A4. Caco-2:human colonic adenocarcinoma CYP:cytochrome P450 H. GORDONII: Hoodia GORDONIILy:Lucifer yellow MRP:multidrug resistance-associated protein P57AS3:P57 Papp:apparent permeability P-gp:P-glycoprotein TEER:transepithelial electrical resistance
Rahul S. Pawar - One of the best experts on this subject based on the ideXlab platform.
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characterization of in vitro pharmacokinetic properties of hoodigogenin a from Hoodia gordonii
Planta Medica, 2010Co-Authors: Vamsi L. M. Madgula, Yatin J Shukla, Rahul S. Pawar, Bharathi Avula, Ikhlas A. Khan, Larry A. Walker, Shabana I. KhanAbstract:: This study was aimed to predict the pharmacokinetic properties of hoodigogenin A, which is the aglycone of the oxypregnane steroidal glycoside P57AS3 (P57) isolated from Hoodia gordonii. A series of in vitro assays was used to predict its gastric, intestinal and metabolic stability, intestinal and blood brain barrier (BBB) transport, protein binding and interaction with major drug metabolising enzymes. In the simulated gastric fluid, hoodigogenin A was stable (2 % degradation in 60 minutes) whereas P57 was unstable (45 % degradation in 30 minutes). In simulated intestinal fluid, P57 was degraded to an extent of 8 % in 180 minutes, while hoodigogenin A was stable. Hoodigogenin A was efficiently transported by passive diffusion across Caco-2 and MDR1-MDCK monolayers with P(app) values in the range of 32 x 10(-6) cm/sec and 22 x 10(-6) cm/sec, respectively. The compound was metabolically unstable in human liver microsomes and S9 fractions with a CL' (int) of 71 and 120 mL/min/kg, respectively and was bound to the plasma proteins to an extent of 92 %. The compound strongly inhibited CYP3A4 activity (IC(50) 3 microM), indicating a possibility of drug-herb/botanical interactions when products containing H. gordonii are used simultaneously with other botanicals/herbs/drugs.
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pregnane glycosides from Hoodia gordonii
Phytochemistry, 2009Co-Authors: Yatin J Shukla, Yuanqing Ding, Rahul S. Pawar, Xingcong Li, Daneel Ferreira, Ikhlas A. KhanAbstract:Abstract Hoodia gordonii is a ‘weight loss’ herb, which has gained popularity in the western countries as an appetite suppressant dietary supplement. Phytochemical study of its aerial parts led to isolation of seven pregnane glycosides (hoodigosides W–Z, hoodistanalosides A–B). Their structures were elucidated by chemical degradation studies and spectroscopic methods, including 1D and 2D NMR and CD spectroscopic methods.
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a rapid method for chemical fingerprint analysis of Hoodia species related genera and dietary supplements using uplc uv ms
Journal of Pharmaceutical and Biomedical Analysis, 2008Co-Authors: Bharathi Avula, Yatin J Shukla, Rahul S. Pawar, Troy J. Smillie, Yan-hong Wang, Ikhlas A. KhanAbstract:Abstract Recently, ultra-performance liquid chromatography (UPLC) has proven to be one of the most promising developments in the area of high-speed chromatographic separations with increased sensitivity and resolution. In this work, a reverse phase chromatographic method was developed using UPLC for the chemical fingerprint analysis of 12 hoodigosides, related genera and dietary supplements. The method is also used for the quantification of P57 in Hoodia species and dietary supplements that claim to contain Hoodia . The analysis was performed on a Waters Acquity UPLC system with an Acquity UPLC BEH C18 column (100 mm × 2.1 mm I.D., 1.7 μm) and a gradient elution of water and acetonitrile, both containing 0.05% formic acid with a run time of 15 min. The calibration curve of P57 showed good linearity ( r 2 > 0.999) within the established range (1–100 μg/mL). The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.3 and 0.9 μg/mL, respectively. The RSD for intra- and inter-day were less than 3.0%, and the recovery efficiency as 97–103%. LC–mass spectrometry coupled with electrospray ionization (ESI) interface method is described for the identification of P57. The developed method was successfully applied to the identification of 12 oxypregnane glycosides in four different species of Hoodia , 23 related genera and 35 dietary supplements that claim to contain H . gordonii . The UPLC profiles of various plant samples were compared for the presence of oxypregnane glycosides. Different sample matrices were successfully analyzed, providing the wide range of applicability of this method, including gels, capsules, tablets, sprays, tea bags, snack bars, powders and juices.
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identification and structural characterization of steroidal glycosides in Hoodia gordonii by ion trap tandem mass spectrometry and liquid chromatography coupled with electrospray ionization time of flight mass spectrometry
Rapid Communications in Mass Spectrometry, 2008Co-Authors: Bharathi Avula, Yatin J Shukla, Rahul S. Pawar, Troy J. Smillie, Yan-hong Wang, Ikhlas A. KhanAbstract:Electrospray ion-trap tandem mass spectrometry (ESI-MS/MS) and high-performance liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry (LC/ESI-TOFMS) were used to identify and characterize eight C-21 steroidal glycosides in Hoodia gordonii. A generalized fragmentation pathway was proposed by comparing the spectra acquired for eight C-21 steroidal glycosides. The steroidal glycosides in Hoodia gordonii have been classified into two major core groups: hoodigenin A and calogenin. Using the ESI-TOF method, the major core peak ions generated by hoodigenin A glycosides are m/z 313 and 295 and by calogenin glycosides are m/z 479, 461, 299 and 281, respectively. In the MS/MS spectra, fragmentation reactions of the [M+Na]+ ion were recorded to provide structural information about the glycosyl and aglycone moieties. The data illustrates the ability of positive mode ESI for the identification of hoodigenin A and calogenin glycosides, including the nature of the hoodigenin A and calogenin core, the number of sugar residues and the type of saccharide moiety. Copyright © 2008 John Wiley & Sons, Ltd.
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hoodigogenin a from Hoodia gordonii
Acta Crystallographica Section E-structure Reports Online, 2008Co-Authors: Yatin J Shukla, Rahul S. Pawar, Frank R. Fronczek, Ikhlas A. KhanAbstract:The title molecule (systematic name: 12-O-β-tigloyl-3β,14β-dihydroxypregn-5-en-20-one), C26H38O5, isolated from aerial parts of Hoodia gordonii, has its steroid A and C rings in chair conformations, its B ring in a half-chair conformation, and its five-membered ring in an envelope conformation. The OH group at the C/D ring junction forms an intramolecular hydrogen bond with the keto substituent. The OH group on the A ring forms an intermolecular hydrogen bond with the tiglate C=O group, propagating [010] chains in the crystal structure.
Yatin J Shukla - One of the best experts on this subject based on the ideXlab platform.
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14β hydroxypregnanes from succulent plants belonging to Hoodia gordonii and caralluma genus extraction biological activities and synthesis
Studies in natural products chemistry, 2013Co-Authors: Yatin J Shukla, Philippe Geoffroy, Ikhlas A. Khan, Michel MieschAbstract:Abstract Caralluma and Hoodia are genera of succulent plants belonging to the subfamily of Asclepiadoideae in the family of Apocynaceae. Caralluma is distributed in dry regions of tropical Asia and Africa, majority of species being indigenous to the Indian subcontinent and the Arabian Peninsula. The genus Hoodia is mainly found in the Kalahari desert regions in Southern Africa. We focus on Caralluma adscendens var. fimbriata and Hoodia gordonii due to their popularity and growing commercial interest during the past 20 years. Indeed, it was claimed that these succulent plants contain bioactive compounds, especially 14β-hydroxypregnane derivatives, which showed appetite-suppressant activity and weight loss properties. This chapter describes the isolation, biological properties, and synthesis of 14β-hydroxypregnane derivatives found in C. adscendens var. fimbriata and H. gordonii .
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characterization of in vitro pharmacokinetic properties of hoodigogenin a from Hoodia gordonii
Planta Medica, 2010Co-Authors: Vamsi L. M. Madgula, Yatin J Shukla, Rahul S. Pawar, Bharathi Avula, Ikhlas A. Khan, Larry A. Walker, Shabana I. KhanAbstract:: This study was aimed to predict the pharmacokinetic properties of hoodigogenin A, which is the aglycone of the oxypregnane steroidal glycoside P57AS3 (P57) isolated from Hoodia gordonii. A series of in vitro assays was used to predict its gastric, intestinal and metabolic stability, intestinal and blood brain barrier (BBB) transport, protein binding and interaction with major drug metabolising enzymes. In the simulated gastric fluid, hoodigogenin A was stable (2 % degradation in 60 minutes) whereas P57 was unstable (45 % degradation in 30 minutes). In simulated intestinal fluid, P57 was degraded to an extent of 8 % in 180 minutes, while hoodigogenin A was stable. Hoodigogenin A was efficiently transported by passive diffusion across Caco-2 and MDR1-MDCK monolayers with P(app) values in the range of 32 x 10(-6) cm/sec and 22 x 10(-6) cm/sec, respectively. The compound was metabolically unstable in human liver microsomes and S9 fractions with a CL' (int) of 71 and 120 mL/min/kg, respectively and was bound to the plasma proteins to an extent of 92 %. The compound strongly inhibited CYP3A4 activity (IC(50) 3 microM), indicating a possibility of drug-herb/botanical interactions when products containing H. gordonii are used simultaneously with other botanicals/herbs/drugs.
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pregnane glycosides from Hoodia gordonii
Phytochemistry, 2009Co-Authors: Yatin J Shukla, Yuanqing Ding, Rahul S. Pawar, Xingcong Li, Daneel Ferreira, Ikhlas A. KhanAbstract:Abstract Hoodia gordonii is a ‘weight loss’ herb, which has gained popularity in the western countries as an appetite suppressant dietary supplement. Phytochemical study of its aerial parts led to isolation of seven pregnane glycosides (hoodigosides W–Z, hoodistanalosides A–B). Their structures were elucidated by chemical degradation studies and spectroscopic methods, including 1D and 2D NMR and CD spectroscopic methods.
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a rapid method for chemical fingerprint analysis of Hoodia species related genera and dietary supplements using uplc uv ms
Journal of Pharmaceutical and Biomedical Analysis, 2008Co-Authors: Bharathi Avula, Yatin J Shukla, Rahul S. Pawar, Troy J. Smillie, Yan-hong Wang, Ikhlas A. KhanAbstract:Abstract Recently, ultra-performance liquid chromatography (UPLC) has proven to be one of the most promising developments in the area of high-speed chromatographic separations with increased sensitivity and resolution. In this work, a reverse phase chromatographic method was developed using UPLC for the chemical fingerprint analysis of 12 hoodigosides, related genera and dietary supplements. The method is also used for the quantification of P57 in Hoodia species and dietary supplements that claim to contain Hoodia . The analysis was performed on a Waters Acquity UPLC system with an Acquity UPLC BEH C18 column (100 mm × 2.1 mm I.D., 1.7 μm) and a gradient elution of water and acetonitrile, both containing 0.05% formic acid with a run time of 15 min. The calibration curve of P57 showed good linearity ( r 2 > 0.999) within the established range (1–100 μg/mL). The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.3 and 0.9 μg/mL, respectively. The RSD for intra- and inter-day were less than 3.0%, and the recovery efficiency as 97–103%. LC–mass spectrometry coupled with electrospray ionization (ESI) interface method is described for the identification of P57. The developed method was successfully applied to the identification of 12 oxypregnane glycosides in four different species of Hoodia , 23 related genera and 35 dietary supplements that claim to contain H . gordonii . The UPLC profiles of various plant samples were compared for the presence of oxypregnane glycosides. Different sample matrices were successfully analyzed, providing the wide range of applicability of this method, including gels, capsules, tablets, sprays, tea bags, snack bars, powders and juices.
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identification and structural characterization of steroidal glycosides in Hoodia gordonii by ion trap tandem mass spectrometry and liquid chromatography coupled with electrospray ionization time of flight mass spectrometry
Rapid Communications in Mass Spectrometry, 2008Co-Authors: Bharathi Avula, Yatin J Shukla, Rahul S. Pawar, Troy J. Smillie, Yan-hong Wang, Ikhlas A. KhanAbstract:Electrospray ion-trap tandem mass spectrometry (ESI-MS/MS) and high-performance liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry (LC/ESI-TOFMS) were used to identify and characterize eight C-21 steroidal glycosides in Hoodia gordonii. A generalized fragmentation pathway was proposed by comparing the spectra acquired for eight C-21 steroidal glycosides. The steroidal glycosides in Hoodia gordonii have been classified into two major core groups: hoodigenin A and calogenin. Using the ESI-TOF method, the major core peak ions generated by hoodigenin A glycosides are m/z 313 and 295 and by calogenin glycosides are m/z 479, 461, 299 and 281, respectively. In the MS/MS spectra, fragmentation reactions of the [M+Na]+ ion were recorded to provide structural information about the glycosyl and aglycone moieties. The data illustrates the ability of positive mode ESI for the identification of hoodigenin A and calogenin glycosides, including the nature of the hoodigenin A and calogenin core, the number of sugar residues and the type of saccharide moiety. Copyright © 2008 John Wiley & Sons, Ltd.
Johan Haverkamp - One of the best experts on this subject based on the ideXlab platform.
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quantification of steroid glycosides from Hoodia gordonii in porcine plasma using high performance liquid chromatography mass spectrometry
Journal of Chromatography A, 2011Co-Authors: Chris J Van Platerink, Leo Abrahamse, Hansgerd Janssen, Brigitte A. Graf, Johan HaverkampAbstract:An HPLC–ESI–MS/MS method using collision induced dissociation – multiple reaction monitoring was developed for the quantification of eight Hoodia gordonii steroid glycosides and their metabolites in porcine plasma samples. The method was validated for the three most important glycosides and was successfully applied also for the related glycosides and metabolites. The limits of quantification were 0.04ngml⁻¹ for the two main steroid glycosides and 0.1ngml⁻¹ for the detiglated metabolites. These limits are sufficiently low to allow monitoring the concentration–time profiles in plasma after feeding H. gordonii. The standard deviations of the intra-day measurements were better than 20% for concentrations below 5ngml⁻¹ and better than 10% for concentrations above 5ngml⁻¹. The method was successfully applied to plasma samples collected from a porcine pharmacokinetics study.
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quantification of steroid glycosides from Hoodia gordonii in porcine plasma using high performance liquid chromatography mass spectrometry
Journal of Chromatography A, 2011Co-Authors: Chris J Van Platerink, Leo Abrahamse, Hansgerd Janssen, Brigitte A. Graf, Johan HaverkampAbstract:An HPLC–ESI–MS/MS method using collision induced dissociation – multiple reaction monitoring was developed for the quantification of eight Hoodia gordonii steroid glycosides and their metabolites in porcine plasma samples. The method was validated for the three most important glycosides and was successfully applied also for the related glycosides and metabolites. The limits of quantification were 0.04ngml⁻¹ for the two main steroid glycosides and 0.1ngml⁻¹ for the detiglated metabolites. These limits are sufficiently low to allow monitoring the concentration–time profiles in plasma after feeding H. gordonii. The standard deviations of the intra-day measurements were better than 20% for concentrations below 5ngml⁻¹ and better than 10% for concentrations above 5ngml⁻¹. The method was successfully applied to plasma samples collected from a porcine pharmacokinetics study.