The Experts below are selected from a list of 3435 Experts worldwide ranked by ideXlab platform
Yoichiro Ito - One of the best experts on this subject based on the ideXlab platform.
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preparative isolation and purification of hydroxyanthraquinones from Rheum officinale baill by high speed counter current chromatography using ph modulated stepwise elution
Journal of Chromatography A, 1999Co-Authors: Fuquan Yang, Tianyou Zhang, Guilian Tian, Haifeng Cao, Qinhui Liu, Yoichiro ItoAbstract:Analytical and preparative high-speed counter-current chromatography was successfully used for the isolation and purification of hydroxyanthraquinones from Rheum officinale Baill (Dahuang) using pH-modulated stepwise elution. Four major components including chrysophanol, emodin, physcion and aloe-emodin were isolated each at over 98% purity.
Tao Chen - One of the best experts on this subject based on the ideXlab platform.
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separation of six compounds including two n butyrophenone isomers and two stibene isomers from Rheum tanguticum maxim by recycling high speed counter current chromatography and preparative high performance liquid chromatography
IEEE Journal of Solid-state Circuits, 2018Co-Authors: Tao Chen, Xue Yang, Nana Wang, Jingyang ZhaoAbstract:Six compounds including two n‐butyrophenone isomers and two stibene isomers were obtained from Rheum tanguticum Maxim. Two n‐butyrophenone isomers with a separation factor of 1.14 were successfully separated by recycling high‐speed counter‐current chromatography after ten cycles. Two stibene isomers were successfully separated by preparative high‐performance liquid chromatography. High‐performance liquid chromatography analysis showed that the purities of the compounds were all over 98%. These compounds were identified as lindleyin, isolindleyin, resveratrol‐4′‐O‐(2″‐O‐galloyl)‐glucopyranoside, resveratrol‐4′‐O‐(6′′‐O‐galloyl)‐glucopyranoside, emodin 1‐O‐β‐d‐glucoside, and 3,5‐dihydroxy‐4′‐methoxystilbene‐3‐O‐β‐d‐glucopyranoside. The results indicated that recycling high‐speed counter‐current chromatography and preparative high‐performance liquid chromatography could be effective combination for the preparation of bioactive compounds from Rheum tanguticum Maxim.
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separation of three anthraquinone glycosides including two isomers by preparative high performance liquid chromatography and high speed countercurrent chromatography from Rheum tanguticum maxim ex balf
IEEE Journal of Solid-state Circuits, 2016Co-Authors: Tao Chen, Chen Chen, Denglang Zou, Yongling Liu, Guoying ZhouAbstract:Anthraquinone glycosides, such as chrysophanol 1-O-β-d-glucoside, chrysophanol 8-O-β-d-glucoside and physion 8-O-β-d-glucoside, are the accepted important active components of Rheum tanguticum Maxim. due to their pharmacological properties: antifungal, anti-microbial, cytotoxic and antioxidant activities. However, an effective method for the separation of the above anthraquinone glycosides from this herb is not currently available. Especially, greater difficulty existed in the separation of the two isomers chrysophanol 1-O-β-d-glucoside and chrysophanol 8-O-β-d-glucoside. This study demonstrated an efficient strategy based on preparative high-performance liquid chromatography and high-speed countercurrent chromatography for the separation of the above anthraquinone glycosides from Rheum tanguticum Maxim. This article is protected by copyright. All rights reserved
Huilan Yue - One of the best experts on this subject based on the ideXlab platform.
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preparative isolation and purification of three stilbene glycosides from the tibetan medicinal plant Rheum tanguticum maxim ex balf by high speed counter current chromatography
Phytochemical Analysis, 2013Co-Authors: Xiaohui Zhao, Fa Han, Huilan YueAbstract:Introduction - Stilbene glycosides are the primary constituents of Rheum tanguticum Maxim. ex Balf., to which different bioactivities has been attributed, including: anti-HIV, anti-oxidant, anti-tumour, anti-malarial, and anti-allergy activity. However, effective methods for the isolation and purification of stilbene glycosides, such as trans-rhapontin, cis-rhapontin and trans-desoxyrhaponticin, from this herb are not currently available. Objective - To develop an efficient method for the preparative isolation and purification of three stilbene glycosides from Rheum tanguticum Maxim. ex Balf. via high-speed counter-current chromatography (HSCCC). Methods - A solvent system composed of chloroform: n-butanol: methanol: water (4:1:3:2, v/v/v/v) was developed for the separation. The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. The flow rate was 1.8 mL/min. The apparatus was controlled at 800 rpm and 25 degrees C, and the effluent was monitored at 280 nm. Chemical constituents were analysed by high-performance liquid chromatography (HPLC), and their structures were identified by H-1- and C-13-NMR. Results - Under the optimised conditions, 25.5 mg trans-rhapontin, 16.0 mg cis-rhapontin and 20.5 mg trans-desoxyrhaponticin were separated from 80 mg crude sample; the isolates had purities of 99.6, 97.2 and 99.2%, respectively. Conclusion - A simple and efficient HSCCC method has been optimised for the preparative separation of stilbene glycosides from Rheum tanguticum Maxim. ex Balf. Copyright (C) 2012 John Wiley & Sons, Ltd.
Jingyang Zhao - One of the best experts on this subject based on the ideXlab platform.
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separation of six compounds including two n butyrophenone isomers and two stibene isomers from Rheum tanguticum maxim by recycling high speed counter current chromatography and preparative high performance liquid chromatography
IEEE Journal of Solid-state Circuits, 2018Co-Authors: Tao Chen, Xue Yang, Nana Wang, Jingyang ZhaoAbstract:Six compounds including two n‐butyrophenone isomers and two stibene isomers were obtained from Rheum tanguticum Maxim. Two n‐butyrophenone isomers with a separation factor of 1.14 were successfully separated by recycling high‐speed counter‐current chromatography after ten cycles. Two stibene isomers were successfully separated by preparative high‐performance liquid chromatography. High‐performance liquid chromatography analysis showed that the purities of the compounds were all over 98%. These compounds were identified as lindleyin, isolindleyin, resveratrol‐4′‐O‐(2″‐O‐galloyl)‐glucopyranoside, resveratrol‐4′‐O‐(6′′‐O‐galloyl)‐glucopyranoside, emodin 1‐O‐β‐d‐glucoside, and 3,5‐dihydroxy‐4′‐methoxystilbene‐3‐O‐β‐d‐glucopyranoside. The results indicated that recycling high‐speed counter‐current chromatography and preparative high‐performance liquid chromatography could be effective combination for the preparation of bioactive compounds from Rheum tanguticum Maxim.
Cheng Huang - One of the best experts on this subject based on the ideXlab platform.
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doi:10.1155/2012/374936 Research Article Rhein Reduces Fat Weight in db/db Mouse and Prevents Diet-Induced Obesity in C57Bl/6 Mouse through the Inhibition of PPARγ Signaling
2016Co-Authors: Cheng HuangAbstract:which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Rheum palmatum has been used most frequently in the weight-reducing formulae in traditional Chinese medicine. However, the components of Rheum palmatum that play the antiobesity role are still uncertain. Here, we tested the weight-reducing effect of two major Rheum palmatum compounds on db/db mouse. We found that rhein (100mg kg−1 day−1), but not emodin, reduced the fat weight in db/db mouse. Using diet-induced obese (DIO) C57BL/6 mice, we identified that rhein blocked high-fat diet-induced obesity, decreased fat mass and the size of white and brown adipocytes, and lowered serum cholesterol, LDL cholesterol, and fasting blood glucose levels in the mice. To elucidate the underlying mechanisms, we used reporter assay and gene expression analysis and found that rhein inhibited peroxisome proliferator-activated receptor γ (PPARγ) transactivity and the expression of its target genes, suggesting that rhein may act as a PPARγ antagonist. Our data indicate that rhein may be a promising choice for antiobesity therapy. 1
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rhein reduces fat weight in db db mouse and prevents diet induced obesity in c57bl 6 mouse through the inhibition of pparγ signaling
Ppar Research, 2012Co-Authors: Yu Zhang, Shengjie Fan, Chunxiao Chu, Cheng HuangAbstract:Rheum palmatum has been used most frequently in the weight-reducing formulae in traditional Chinese medicine. However, the components of Rheum palmatum that play the antiobesity role are still uncertain. Here, we tested the weight-reducing effect of two major Rheum palmatum compounds on db/db mouse. We found that rhein (100 mg kg(-1) day(-1)), but not emodin, reduced the fat weight in db/db mouse. Using diet-induced obese (DIO) C57BL/6 mice, we identified that rhein blocked high-fat diet-induced obesity, decreased fat mass and the size of white and brown adipocytes, and lowered serum cholesterol, LDL cholesterol, and fasting blood glucose levels in the mice. To elucidate the underlying mechanisms, we used reporter assay and gene expression analysis and found that rhein inhibited peroxisome proliferator-activated receptor γ (PPARγ) transactivity and the expression of its target genes, suggesting that rhein may act as a PPARγ antagonist. Our data indicate that rhein may be a promising choice for antiobesity therapy.
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Rhein Reduces Fat Weight in db/db Mouse and Prevents Diet-Induced Obesity in C57Bl/6 Mouse through the Inhibition of PPARγ Signaling
Hindawi Limited, 2012Co-Authors: Yu Zhang, Shengjie Fan, Chunxiao Chu, Cheng HuangAbstract:Rheum palmatum has been used most frequently in the weight-reducing formulae in traditional Chinese medicine. However, the components of Rheum palmatum that play the antiobesity role are still uncertain. Here, we tested the weight-reducing effect of two major Rheum palmatum compounds on db/db mouse. We found that rhein (100 mg kg−1 day−1), but not emodin, reduced the fat weight in db/db mouse. Using diet-induced obese (DIO) C57BL/6 mice, we identified that rhein blocked high-fat diet-induced obesity, decreased fat mass and the size of white and brown adipocytes, and lowered serum cholesterol, LDL cholesterol, and fasting blood glucose levels in the mice. To elucidate the underlying mechanisms, we used reporter assay and gene expression analysis and found that rhein inhibited peroxisome proliferator-activated receptor γ (PPARγ) transactivity and the expression of its target genes, suggesting that rhein may act as a PPARγ antagonist. Our data indicate that rhein may be a promising choice for antiobesity therapy
