The Experts below are selected from a list of 1449 Experts worldwide ranked by ideXlab platform
Zhihong Jiang - One of the best experts on this subject based on the ideXlab platform.
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high performance liquid chromatography coupled with tandem mass spectrometry applied for metabolic study of Ginsenoside Rb1 on rat
Analytical Biochemistry, 2006Co-Authors: Tianxiu Qian, Zhihong JiangAbstract:Abstract Liquid chromatography coupled with mass spectrometry and tandem mass spectrometry has been applied to investigate the in vivo metabolism of Ginsenoside Rb 1 in rat. Both positive electrospray ionization mass spectrometry and negative electrospray ionization mass spectrometry were used to identify the Rb 1 and its metabolites in rat plasma, urine, and feces samples. Oxygenation and deglycosylation were found to be the major metabolic pathways of Rb 1 in rat. A total of nine metabolites were detected in urine and feces samples collected after intravenous and oral administration. Deglycosylated metabolism of Rb 1 generated other Ginsenosides as the major metabolites, such as Rd, Rg 3 or F 2 , Rh 2 , or C-K. This result indicates that the Ginsenoside Rb 1 has many pharmacological activities and could be used as a prodrug.
Deokchun Yang - One of the best experts on this subject based on the ideXlab platform.
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bioconversion of Ginsenoside Rb1 to compound k using leuconostoc lactis dc201
Korean Journal of Plant Resources, 2011Co-Authors: Jin-ying Piao, Lin-hu Quan, Jin-woo Min, Dong-uk Yang, Yeonju Kim, Seonheui Son, Sangmok Kim, Deokchun YangAbstract:Ginseng (Panax ginseng) is frequently used in Asian countries as a traditional medicine. The major components of ginseng are Ginsenosides. Among these, Ginsenoside compound K has been reported to prevent the formation of malignancy and metastasis of cancer by blocking the formation of tumor and suppressing the invasion of cancer cells. In this study, Ginsenoside Rb1 was converted into compound K, via secreted β-glucosidase enzyme from the Leuconostoc lactis DC201 isolated, which was extracted from Kimchi. The strain DC201 was suspended and cultured in MRS broth at 37℃. Subsequently, the residue from the cultured broth supernatant was precipitated with EtOH and then dissolved in 20 mM sodium phosphate buffer (pH 6.0) to obtain an enzyme liquid. Meanwhile, the crude enzyme solution was mixed with Ginsenoside Rb 1 at a ratio of 1:4 (v/v).The reaction was carried out at 30℃ and 190 rpm for 72 hours, and then analyzed by TLC and HPLC. The result showed that Ginsenoside Rb 1 was transformed into compound K after 72 hours post reaction.
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Biotransformation of Ginsenoside Rb 1 to Prosapogenins, Gypenoside XVII, Ginsenoside Rd, Ginsenoside F 2 , and Compound K by Leuconostoc mesenteroides DC102
Journal of Ginseng Research, 2011Co-Authors: Lin-hu Quan, Jin-woo Min, Dong-uk Yang, Jin-ying Piao, Ho-bin Kim, Sang-rae Kim, Deokchun YangAbstract:Ginsenoside Rb 1 is the main component in Ginsenosides. It is a protopanaxadiol-type Ginsenoside that has a dammarane-type triterpenoid as an aglycone. In this study, Ginsenoside Rb 1 was transformed into gypenoside XVII, Ginsenoside Rd, Ginsenoside F 2 and compound K by glycosidase from Leuconostoc mesenteroides DC102. The optimum time for the conversion was about 72 h at a constant pH of 6.0 to 8.0 and the optimum temperature was about 30℃. Under optimal conditions, Ginsenoside Rb 1 was decomposed and converted into compound K by 72 h post-reaction (99%). The enzymatic reaction was analyzed by high-performance liquid chromatography, suggesting the transformation pathway: Ginsenoside Rb 1 →gypenoside XVII and Ginsenoside Rd→Ginsenoside F 2 →compound K.
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microbial conversion of Ginsenoside Rb1 to minor Ginsenoside f2 and gypenoside xvii by intrasporangium sp gs603 isolated from soil
Journal of Microbiology and Biotechnology, 2007Co-Authors: Leqin Cheng, Juryun Na, Myunho Bang, Deokchun YangAbstract:: A new strain, GS603, having beta-glucosidase activity was isolated from soil of a ginseng field, and its ability to convert major Ginsenoside Rb(1) to minor Ginsenoside or gypenoside was studied. Strain GS603 was identified as an Intrasporangium species by phylogenetic analysis and showed high Ginsenoside-converting activity in LB and TSA broth but not in nutrient broth. The culture broth of the strain GS603 could convert Ginsenoside Rb(1 )into two metabolites, which were analyzed by TLC and HPLC and shown to be the minor Ginsenoside F(2) and gypenoside XVII by NMR.
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Microbial conversion of major Ginsenoside Rb(1) to pharmaceutically active minor Ginsenoside rd.
Journal of microbiology (Seoul Korea), 2005Co-Authors: Myung Kyum Kim, Jun-won Lee, Ki-young Lee, Deokchun YangAbstract:More than seventy strains of aerobic bacteria showing beta-glucosidase activity were isolated from a ginseng field, using a newly designed Esculin-R2A agar, and identified by their 16S rRNA gene sequences. Of these microorganisms, twelve strains could convert the major Ginsenoside, Rb(1), to the pharmaceutically active minor Ginsenoside Rd. Three strains, Burkholderia pyrrocinia GP16, Bacillus megaterium GP27 and Sphingomonas echinoides GP50, were phylogenetically studied, and observed to be most potent at converting Ginsenoside Rb(1) almost completely within 48 h, as shown by TLC and HPLC analyses.
Dong Hwan Sohn - One of the best experts on this subject based on the ideXlab platform.
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simultaneous determination of Ginsenoside Rb1 and rg1 in human plasma by liquid chromatography mass spectrometry
Journal of Pharmaceutical and Biomedical Analysis, 2004Co-Authors: Hye Young Ji, Seung Goo Chang, Dong Hwan SohnAbstract:Abstract A liquid chromatographic–mass spectrometric (LC/MS) method for the simultaneous determination of Ginsenoside Rb 1 and Rg 1 in human plasma was developed. The method involved the protein precipitation followed by analysis of Ginsenoside Rb 1 and Rg 1 in an Atlantis C 18 column with the gradient elution of acetonitrile and ammonium formate (10 mM, pH 3.0) at a flow rate of 0.2 ml/min. The analytes were determined using electrospray negative ionization mass spectrometry in the selected ion monitoring mode. The standard curves for Ginsenoside Rb 1 and Rg 1 were linear over the concentration range of 10.0–1000 ng/ml. The lower limit of quantification was 10.0 ng/ml using 100 μl plasma sample. The coefficient of variation of intra- and inter-day assays for Ginsenoside Rb 1 and Rg 1 at three quality control levels ranged from 1.0 to 6.8% and 5.4 to 9.8%, respectively. Ginsenoside Rb 1 and Rg 1 were stable in blank human plasma at room temperature for 24 h and following three freeze–thaw cycles.
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Simultaneous determination of Ginsenoside Rb1 and Rg1 in human plasma by liquid chromatography–mass spectrometry
Journal of pharmaceutical and biomedical analysis, 2004Co-Authors: Hye Won Lee, Seung Goo Chang, Dong Hwan Sohn, Hae Kyoung Kim, Hui Hyun Kim, Jaebaek Kim, Hye Suk LeeAbstract:Abstract A liquid chromatographic–mass spectrometric (LC/MS) method for the simultaneous determination of Ginsenoside Rb 1 and Rg 1 in human plasma was developed. The method involved the protein precipitation followed by analysis of Ginsenoside Rb 1 and Rg 1 in an Atlantis C 18 column with the gradient elution of acetonitrile and ammonium formate (10 mM, pH 3.0) at a flow rate of 0.2 ml/min. The analytes were determined using electrospray negative ionization mass spectrometry in the selected ion monitoring mode. The standard curves for Ginsenoside Rb 1 and Rg 1 were linear over the concentration range of 10.0–1000 ng/ml. The lower limit of quantification was 10.0 ng/ml using 100 μl plasma sample. The coefficient of variation of intra- and inter-day assays for Ginsenoside Rb 1 and Rg 1 at three quality control levels ranged from 1.0 to 6.8% and 5.4 to 9.8%, respectively. Ginsenoside Rb 1 and Rg 1 were stable in blank human plasma at room temperature for 24 h and following three freeze–thaw cycles.
Xiao Ling Fang - One of the best experts on this subject based on the ideXlab platform.
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oral absorption of Ginsenoside Rb1 using in vitro and in vivo models
Planta Medica, 2006Co-Authors: Yunjuan Wu, Xiao Ling FangAbstract:This research attempts to clarify the cause for poor oral absorption of Ginsenoside Rb 1 (Rb 1 ), one main ingredient of the well known Panax notoginseng saponins (PNS) for curing hemorrhage. Caco-2 cell monolayers were used as an in vitro model to reveal the transport mechanism of Rb 1 across the intestinal mucosa. Moreover, the serum concentration-time profiles of Rb 1 after tail venous (IV), portal venous (PV), intraduodenal (ID) and peroral (PO) administration to rats were compared to evaluate the first-pass effects of stomach, intestine and liver. In vitro experiments showed that uptake by Caco-2 cell monolayers was temperature dependent, but was not influenced by cyclosporine A and ketoconazole. The change in the apical pH showed no obvious effects on the uptake of Rb 1 . The uptake and transport were non-saturable, and flux from the apical compartment to the basolateral compartment (A-B) increased linearly with increasing concentration, which indicated a passive transport. Meanwhile, an apparent permeability coefficient of (5.90 ± 1.02)×10 -8 cm/s (C 0 = 1 mg/mL) predicted an incomplete absorption. The investigation on the pharmacokinetic behavior of Rb 1 after different routes of administration to rats showed a significant difference between PO (F PO was 0.64%), ID (F ID was 2.46%) and PV (F PV was 59.49%) administration, and the first-pass effect of the intestine is more significant than that of the stomach and liver in the absorption process. In summary, elimination in the stomach, large intestine and liver contributed to the poor absorption of Rb 1 , but the low membrane permeability might be a more important factor dominating the extent of absorption.
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Pharmacokinetics and bioavailability of Ginsenoside Rb1 and Rg1 from Panax notoginseng in rats.
Journal of ethnopharmacology, 2003Co-Authors: Xiao Ling Fang, Dao Feng ChenAbstract:Panax notoginseng is used as a therapeutic agent to stop haemorrhages and a tonic to promote health in Chinese medicine. Currently saponins of P. notoginseng (PNS) are especially given attentions for their hemorheological properties. The pharmacokinetic profiles of the main PNS are still not accurately investigated. Therefore, our preliminary aim is to elucidate the pharmacokinetic features of Ginsenoside Rb(1) (Rb(1)) and Ginsenoside Rg(1) (Rg(1)), two of the main PNS in rats. Firstly, quantitive analysis of Rb(1) and Rg(1) in saponins of P. notoginseng was studied and the most suitable assay method by HPLC for blood sample were established. Then Rb(1) and Rg(1) in the same serum were determined after administering PNS to rats. The decline of Rb(1) in serum could be described by a two-compartment model. The half-life of alpha phase was 23.40 min and that of beta phase was 17.96 h. Rb(1) was absoRbed from the digestive tract and the bioavailability via P.O. was 4.35%. The pharmacokinetics of Rg(1) in rats also could be described by a two-compartment model. The half-lives of Rg(1) were 24.23 min for alpha phase and 14.13 h for beta phase. Rg(1) could be absoRbed in the digestive tract and the oral bioavailability was 18.40%. Both of the low oral bioavailability of Rb(1) and rapid reduction of Rg(1) in blood indicated that formula modification is necessary.
Tianxiu Qian - One of the best experts on this subject based on the ideXlab platform.
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high performance liquid chromatography coupled with tandem mass spectrometry applied for metabolic study of Ginsenoside Rb1 on rat
Analytical Biochemistry, 2006Co-Authors: Tianxiu Qian, Zhihong JiangAbstract:Abstract Liquid chromatography coupled with mass spectrometry and tandem mass spectrometry has been applied to investigate the in vivo metabolism of Ginsenoside Rb 1 in rat. Both positive electrospray ionization mass spectrometry and negative electrospray ionization mass spectrometry were used to identify the Rb 1 and its metabolites in rat plasma, urine, and feces samples. Oxygenation and deglycosylation were found to be the major metabolic pathways of Rb 1 in rat. A total of nine metabolites were detected in urine and feces samples collected after intravenous and oral administration. Deglycosylated metabolism of Rb 1 generated other Ginsenosides as the major metabolites, such as Rd, Rg 3 or F 2 , Rh 2 , or C-K. This result indicates that the Ginsenoside Rb 1 has many pharmacological activities and could be used as a prodrug.