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Tianwei Tan - One of the best experts on this subject based on the ideXlab platform.
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investigation of the inclusions of puerarin and daidzin with β cyclodextrin by molecular dynamics simulation
Journal of Physical Chemistry B, 2010Co-Authors: Haiyang Zhang, Wei Feng, Tianwei TanAbstract:Puerarin and daidzin, two major isoflavonoids of Radix Puerariae, are widely adopted in traditional Chinese medicine. Foundational aspects related to separating the two compounds are essential to d...
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Purification of the isoflavonoid puerarin by adsorption chromatography on cross-linked 12% agarose.
Journal of chromatography. A, 2004Co-Authors: Tianwei Tan, Jan-christer JansonAbstract:The isoflavonoid puerarin in extracts of the well-known traditional Chinese drug Radix Puerariae (root of the plant Pueraria lobata) can be separated from other isoflavonoids by adsorption chromatography on the cross-linked 12% agarose gel Superose 12 equilibrated in distilled water. The adsorption is totally quenched by the addition of 50% acetic acid. The separation of the isoflavonoids is tentatively ascribed to interaction with the residues of the cross-linking reagents used in the manufacturing process of Superose 12. Thus, no useful separation can be achieved with non-cross-linked 12% agarose gel media. Symmetric elution profiles at high sample loadings (16 mg on a 24 ml column) suggest linear adsorption isotherms for the isoflavonoids.
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purification of the isoflavonoid puerarin by adsorption chromatography on cross linked 12 agarose
Journal of Chromatography A, 2004Co-Authors: Tianwei Tan, Jan-christer JansonAbstract:The isoflavonoid puerarin in extracts of the well-known traditional Chinese drug Radix Puerariae (root of the plant Pueraria lobata) can be separated from other isoflavonoids by adsorption chromatography on the cross-linked 12% agarose gel Superose 12 equilibrated in distilled water. The adsorption is totally quenched by the addition of 50% acetic acid. The separation of the isoflavonoids is tentatively ascribed to interaction with the residues of the cross-linking reagents used in the manufacturing process of Superose 12. Thus, no useful separation can be achieved with non-cross-linked 12% agarose gel media. Symmetric elution profiles at high sample loadings (16 mg on a 24 ml column) suggest linear adsorption isotherms for the isoflavonoids.
Jan-christer Janson - One of the best experts on this subject based on the ideXlab platform.
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Purification of the isoflavonoid puerarin by adsorption chromatography on cross-linked 12% agarose.
Journal of chromatography. A, 2004Co-Authors: Tianwei Tan, Jan-christer JansonAbstract:The isoflavonoid puerarin in extracts of the well-known traditional Chinese drug Radix Puerariae (root of the plant Pueraria lobata) can be separated from other isoflavonoids by adsorption chromatography on the cross-linked 12% agarose gel Superose 12 equilibrated in distilled water. The adsorption is totally quenched by the addition of 50% acetic acid. The separation of the isoflavonoids is tentatively ascribed to interaction with the residues of the cross-linking reagents used in the manufacturing process of Superose 12. Thus, no useful separation can be achieved with non-cross-linked 12% agarose gel media. Symmetric elution profiles at high sample loadings (16 mg on a 24 ml column) suggest linear adsorption isotherms for the isoflavonoids.
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purification of the isoflavonoid puerarin by adsorption chromatography on cross linked 12 agarose
Journal of Chromatography A, 2004Co-Authors: Tianwei Tan, Jan-christer JansonAbstract:The isoflavonoid puerarin in extracts of the well-known traditional Chinese drug Radix Puerariae (root of the plant Pueraria lobata) can be separated from other isoflavonoids by adsorption chromatography on the cross-linked 12% agarose gel Superose 12 equilibrated in distilled water. The adsorption is totally quenched by the addition of 50% acetic acid. The separation of the isoflavonoids is tentatively ascribed to interaction with the residues of the cross-linking reagents used in the manufacturing process of Superose 12. Thus, no useful separation can be achieved with non-cross-linked 12% agarose gel media. Symmetric elution profiles at high sample loadings (16 mg on a 24 ml column) suggest linear adsorption isotherms for the isoflavonoids.
Albert S. C. Chan - One of the best experts on this subject based on the ideXlab platform.
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Seasonal variations in the isoflavonoids of Radix Puerariae
Phytochemical analysis : PCA, 2007Co-Authors: Chen Sibao, Yang Da-jian, Chen Shilin, Xu Hongxi, Albert S. C. ChanAbstract:The variations in isoflavonoid content in Radix Puerariae, the root of Pueraria lobata (Wild) Ohwi, have been examined in order to determine the optimum time to harvest the herb. Total isoflavonoid contents have been analysed by a UV spectrophotometric method whilst HPLC with photodiode array detection has been used to monitor the contents of seven major individual isoflavonoids, namely, 3'-hydroxypuerarin, puerarin, 3'-methoxypuerarin, daidzin, genistin, formononetin-7-glucoside and daidzein. Ninety-six samples of Radix Puerariae of different ages and harvested in different months were collected and analysed. The results clearly showed that 3-year-old roots harvested in January have the highest yields of isoflavonoid compounds. Moreover, the results obtained by both methods have a strong correlation. This suggested that the simple and fast UV spectrophotometric method could be used for monitoring the phytochemical quality of Radix Puerariae.
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Seasonal variations in the isoflavonoids of Radix Puerariae
Phytochemical analysis : PCA, 2007Co-Authors: Chen Sibao, Yang Da-jian, Chen Shilin, Xu Hongxi, Albert S. C. ChanAbstract:The variations in isoflavonoid content in Radix Puerariae, the root of Pueraria lobata (Wild) Ohwi, have been examined in order to determine the optimum time to harvest the herb. Total isoflavonoid contents have been analysed by a UV spectrophotometric method whilst HPLC with photodiode array detection has been used to monitor the contents of seven major individual isoflavonoids, namely, 3′-hydroxypuerarin, puerarin, 3′-methoxypuerarin, daidzin, genistin, formononetin-7-glucoside and daidzein. Ninety-six samples of Radix Puerariae of different ages and harvested in different months were collected and analysed. The results clearly showed that 3-year-old roots harvested in January have the highest yields of isoflavonoid compounds. Moreover, the results obtained by both methods have a strong correlation. This suggested that the simple and fast UV spectrophotometric method could be used for monitoring the phytochemical quality of Radix Puerariae. Copyright © 2007 John Wiley & Sons, Ltd.
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high performance thin layer chromatographic fingerprints of isoflavonoids for distinguishing between radix Puerariae lobate and radix Puerariae thomsonii
Journal of Chromatography A, 2006Co-Authors: Sibao Chen, Albert S. C. Chan, Heping Liu, Runtao Tian, Dajian Yang, Shilin Chen, Peishan XieAbstract:The roots of Pueraria lobata (Wild.) Ohwi and Pueraria thomsonii Benth have been officially recorded in all editions of Chinese Pharmacopoeia under the same monograph 'Gegen' (Radix Puerariae, RP). However, in its 2005 edition, the two species were separated into both individual monographs, namely 'Gegen' (Radix Puerariae Lobatae, RPL) and 'Fenge' (Radix Puerariae Thomsonii, RPT), respectively, due to their obvious content discrepancy of puerarin, the major active constituent. In present paper, the fingerprint of high-performance thin-layer chromatography (HPTLC) combining digital scanning profiling was developed to identify and distinguish the both species in detail. The unique properties of the HPTLC fingerprints were validated by analyzing ten batches of Pueraria lobata and P. thomsonii samples, respectively. The common pattern of the HPTLC images of the roots of Pueraria spp. and the respective different ratios of the chemical distribution can directly discern the two species. The corresponding digital scanning profiles provided an easy way for quantifiable comparison among the samples. Obvious difference in ingredient content and HPTLC patterns of the two species questioned their bio-equivalence and explained that recording both species separately in the current edition of Chinese Pharmacopoeia (2005 edition) is reasonable due to not only the content of major constituent, puerarin, but also the peak-to-peak distribution in the fingerprint and integration value of the total components. Furthermore, the HPTLC fingerprint is also suitable for rapid and simple authentication and comparison of the subtle difference among samples with identical plant resource but different geographic locations.
Yuping Duan - One of the best experts on this subject based on the ideXlab platform.
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microwave assisted extraction of effective constituents from a chinese herbal medicine radix Puerariae
Analytica Chimica Acta, 2001Co-Authors: Yuping DuanAbstract:Microwave-assisted extraction of the puerarin from the Chinese herbal medicine Radix Puerariae can be completed in 1 min. The yield of puerarin extracted from Radix Puerariae under different microwave processing conditions are compared in this paper. It was shown that the microwave irradiation did not destroy the structure or molecule of the puerarin. Solvent, microwave processing time and the temperature and pressure in the sample vessel are the main factors that affect microwave-assisted extraction of effective constituents from Radix Puerariae.
Jialin Tao - One of the best experts on this subject based on the ideXlab platform.
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hplc method for the determination and pharmacokinetic studies on puerarin in cerebral ischemia reperfusion rat plasma after intravenous administration of Puerariae radix isoflavone
Journal of Pharmaceutical and Biomedical Analysis, 2005Co-Authors: Bin Yan, Dongming Xing, Yi Ding, Jialin TaoAbstract:Abstract A new HPLC method for the determination of puerarin in cerebral ischemia reperfusion rat plasma is introduced. Puerarin, the principal bioactive component of Puerariae radix isoflavone, was extracted from plasma by methanol. The HPLC separation was then performed on a reversed-phase C18 column using water–acetonitrile (89:11, v/v) as eluting solvent system, and UV detection at 252 nm to measure the analyte with a limit of quantitation about 9.44 ng ml −1 . The calibration curve for puerarin was linear ( r = 0.9998) in the concentration range of 9.44–1208.00 ng ml −1 , both intra- and inter-day precision of the puerarin were determined and their coefficient of variation did not exceed 10%. The validated method has been successfully applied for pharmacokinetic studies of puerarin from rat plasma after intravenous administration of Puerariae radix isoflavone. Another novel finding of this study was that the elimination rate of puerarin was significantly slower in the cerebral ischemia reperfusion rat than in the normal rat, judging by the pharmacokinetic parameters obtained. Since Puerariae radix isoflavone was mainly administrated to the patients suffering from cerebralvascular diseases, the pharmacokinetic studies performed on the pathological animal models were suitable references for clinical application.