The Experts below are selected from a list of 165 Experts worldwide ranked by ideXlab platform
Madan M Gupta - One of the best experts on this subject based on the ideXlab platform.
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liquid chromatographic determination of <B>SennosideB>s in cassia angustifolia leaves
Journal of AOAC International, 2006Co-Authors: Alpana Srivastava, Richa Pandey, R K Verma, Madan M GuptaAbstract:: A simple liquid chromatographic method was developed for the determination of <B>SennosideB>s B and A in leaves of Cassia angustifolia. These compounds were extracted from leaves with a mixture of methanol-water (70 + 30, v/v) after defatting with hexane. Analyte separation and quantitation were achieved By gradient reversed-phase liquid chromatography and UV aBsorBance at 270 nm using a photodiode array detector. The method involves the use of an RP-18 Lichrocart reversed-phase column (5 microm, 125 x 4.0 mm id) and a Binary gradient moBile-phase profile. The various other aspects of analysis, namely, peak purity, similarity, recovery, repeataBility, and roBustness, were validated. Average recoveries of 98.5 and 98.6%, with a coefficient of variation of 0.8 and 0.3%, were oBtained By spiking sample solution with 3 different concentration solutions of standards (60, 100, and 200 microg/mL). Detection limits were 10 microg/mL for <B>SennosideB> B and 35 microg/mL for <B>SennosideB> A, present in the sample solution. The quantitation limits were 28 and 100 microg/mL. The analytical method was applied to a large numBer of senna leaf samples. The new method provides a reliaBle tool for rapid screening of C. angustifolia samples in large numBers, which is needed in Breeding/genetic engineering and genetic mapping experiments.
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reverse phase high performance liquid chromatography of <B>SennosideB>s in cassia angustifolia
Phytochemical Analysis, 1996Co-Authors: R K Verma, G C Uniyal, S P Singh, J R Sharma, Madan M GuptaAbstract:A rapid and simple reverse-phase high performance liquid chromatographic method has Been developed for the quantitative estimation of the medicinally useful laxative principles <B>SennosideB> A and <B>SennosideB> B in senna. Using a Bondapak C,, column eluted with methano1:water:acetic acid:tetrahydrofuran (60:38:2:2) Both compounds were well resolved with recoveries of 97 and 96% respectively.
R K Verma - One of the best experts on this subject based on the ideXlab platform.
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liquid chromatographic determination of <B>SennosideB>s in cassia angustifolia leaves
Journal of AOAC International, 2006Co-Authors: Alpana Srivastava, Richa Pandey, R K Verma, Madan M GuptaAbstract:: A simple liquid chromatographic method was developed for the determination of <B>SennosideB>s B and A in leaves of Cassia angustifolia. These compounds were extracted from leaves with a mixture of methanol-water (70 + 30, v/v) after defatting with hexane. Analyte separation and quantitation were achieved By gradient reversed-phase liquid chromatography and UV aBsorBance at 270 nm using a photodiode array detector. The method involves the use of an RP-18 Lichrocart reversed-phase column (5 microm, 125 x 4.0 mm id) and a Binary gradient moBile-phase profile. The various other aspects of analysis, namely, peak purity, similarity, recovery, repeataBility, and roBustness, were validated. Average recoveries of 98.5 and 98.6%, with a coefficient of variation of 0.8 and 0.3%, were oBtained By spiking sample solution with 3 different concentration solutions of standards (60, 100, and 200 microg/mL). Detection limits were 10 microg/mL for <B>SennosideB> B and 35 microg/mL for <B>SennosideB> A, present in the sample solution. The quantitation limits were 28 and 100 microg/mL. The analytical method was applied to a large numBer of senna leaf samples. The new method provides a reliaBle tool for rapid screening of C. angustifolia samples in large numBers, which is needed in Breeding/genetic engineering and genetic mapping experiments.
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reverse phase high performance liquid chromatography of <B>SennosideB>s in cassia angustifolia
Phytochemical Analysis, 1996Co-Authors: R K Verma, G C Uniyal, S P Singh, J R Sharma, Madan M GuptaAbstract:A rapid and simple reverse-phase high performance liquid chromatographic method has Been developed for the quantitative estimation of the medicinally useful laxative principles <B>SennosideB> A and <B>SennosideB> B in senna. Using a Bondapak C,, column eluted with methano1:water:acetic acid:tetrahydrofuran (60:38:2:2) Both compounds were well resolved with recoveries of 97 and 96% respectively.
Norihiro Kobayashi - One of the best experts on this subject based on the ideXlab platform.
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simultaneous determination of anthraquinones in rhuBarB By high performance liquid chromatography and capillary electrophoresis
Journal of Chromatography A, 2007Co-Authors: Junko Koyama, Izumi Morita, Norihiro KobayashiAbstract:ABstract High-performance liquid chromatography (HPLC) and capillary electrophoresis (CE) were compared to simultaneously determine and separate 11 anthraquinones from rhuBarB, including emodin, chrysophanol, rhein and their glucosides, aloe-emodin, <B>SennosideB> A, and <B>SennosideB> B. A UV-diode array detector (DAD) at 254 nm with a gradient elution of acetonitrile/water (method A: 0 min 6:94, 12 min 12:88, 15 min 20:80, 40 min 25:75, 53 min 55:45, 55 min 100:0; method B: 0 min 5:95, 2 min 15:85, 5 min 20:80, 12 min 25:75, 15 min 50:50, 19 min 98:2) at 28(±1) °C (method A) and 30–60 °C (method B) in HPLC or with 0.03 M Borate Buffer (pH 10.0) containing 25% (v/v) acetonitrile with 0.002 M 2,6-di- O -methyl-β-cyclodextrin (CD) and 0.005 M α-CD in CE effectively detected this separation in 25 min. The detection limits of anthraquinones from rhuBarB were in the 0.02–0.2 μg/mL and 0.1–0.8 μg/mL ranges for HPLC and CE, respectively. The estaBlished HPLC and CE methods are suitaBle for quantitative determination of emodin, chrysophanol, aloe-emodin, emodin-1-β- d -glucoside, emodin-8-β- d -glucoside, chrysophanol-1-β- d -glucoside, chrysophanol-8-β- d -glucoside, and rhein-8-β- d -glucoside.
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simultaneous determination of anthraquinones their 8 β d glucosides and <B>SennosideB>s of rhei rhizoma By capillary electrophoresis
Chemical & Pharmaceutical Bulletin, 2005Co-Authors: Junko Koyama, Izumi Morita, Hirotaka Fujiyoshi, Norihiro KobayashiAbstract:The simultaneous separation and determination of major anthraquinones (emodin, chrysophanol, rhein and their glucosides, aloe-emodin, <B>SennosideB> A, and <B>SennosideB> B) of Rhei Rhizoma were achieved By cyclodextrin modified capillary zone electrophoresis. The running electrolyte used in this method was 0.005 M α-cyclodextrin in 0.03 M Borate Buffer (pH 10.0) containing 20% acetonitrile, with an applied voltage of 20 kV.
G C Uniyal - One of the best experts on this subject based on the ideXlab platform.
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reverse phase high performance liquid chromatography of <B>SennosideB>s in cassia angustifolia
Phytochemical Analysis, 1996Co-Authors: R K Verma, G C Uniyal, S P Singh, J R Sharma, Madan M GuptaAbstract:A rapid and simple reverse-phase high performance liquid chromatographic method has Been developed for the quantitative estimation of the medicinally useful laxative principles <B>SennosideB> A and <B>SennosideB> B in senna. Using a Bondapak C,, column eluted with methano1:water:acetic acid:tetrahydrofuran (60:38:2:2) Both compounds were well resolved with recoveries of 97 and 96% respectively.
J R Sharma - One of the best experts on this subject based on the ideXlab platform.
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reverse phase high performance liquid chromatography of <B>SennosideB>s in cassia angustifolia
Phytochemical Analysis, 1996Co-Authors: R K Verma, G C Uniyal, S P Singh, J R Sharma, Madan M GuptaAbstract:A rapid and simple reverse-phase high performance liquid chromatographic method has Been developed for the quantitative estimation of the medicinally useful laxative principles <B>SennosideB> A and <B>SennosideB> B in senna. Using a Bondapak C,, column eluted with methano1:water:acetic acid:tetrahydrofuran (60:38:2:2) Both compounds were well resolved with recoveries of 97 and 96% respectively.
