Biomedical subjects

Guorong Fan

Publications and source records attributed to Guorong Fan.

23 records · Page 2Linked to original sources

PubMed2005

Application of preparative high-speed counter-current chromatography for isolation and separation of schizandrin and gomisin A from Schisandra chinensis.

Following an initial cleaning-up step on the D101 macroporous resin, a preparative high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (1:0.9:0.9:1, v/v) was used to isolate and separate schizandrin and gomisin A from Schisandra chinensis. A total of 107 mg schizandrin and 36 mg gomisin A with purities of 99.5% and 99.1% were obtained from 400 mg crude extract in one-step elution and less than 3 h, and the structure identification was performed by UV, IR, MS, 1H NMR and 13C NMR.

Chromatography, High Pressure Liquid↗

PubMed2005

Stereoselective pharmacokinetics of tetrahydropalmatine after oral administration of (-)-enantiomer and the racemate.

Tetrahydropalmatine (THP) is a biologically active ingredient isolated from a traditional Chinese herb Rhizoma corydalis (yanhusuo). THP is a racemic mixture which contains 50% of the (+) and 50% of (-) enantiomer. The (-) enantiomer accounts for most of the analgesic effects. Plasma concentrations of THP enantiomers were analyzed by chiral high-performance liquid chromatography (HPLC) on a Chiralcel OJ column with quantification by UV at 230 nm. The method was used to determine the pharmacokinetics of THP enantiomers in rats and dogs after oral administration of rac-THP or (-)-THP. The pharmacokinetic profiles of the two enantiomers after dosing with rac-THP were significantly different both in rats and dogs. The mean C(max) and AUC(0-infinity) values in rats were 1.93 +/- 0.36 microg/ml and 6.65 +/- 2.34 microg x h/ml for the (-) enantiomer, and 1.11 +/- 0.25 microg/ml and 2.03 +/- 0.45 microg x h/ml for the (+) enantiomer. The mean C(max) and AUC(0-infinity) in dogs were 1.60 +/- 0.81 microg/ml and 9.88 +/- 2.58 microg x h/ml for the (-) enantiomer, while 0.36 +/- 0.21 microg/ml and 1.22 +/- 0.40 microg x h/ml for the (+) enantiomer. rac-THP at 40 mg/kg and (-)-THP at 20 mg/kg had very similar plasma concentration-time profiles, and C(max), AUC(0-infinity), and t(1/2) of the (-) enantiomer in both rats and dogs, indicating that the two treatments were equivalent with respect to the pharmacokinetic properties of the (-) enantiomer.

Administration, Oral↗

PubMed2005

Preparative separation of isovitexin and isoorientin from Patrinia villosa Juss by high-speed counter-current chromatography.

High-speed counter-current chromatography (HSCCC) with a solvent system composed of ethyl acetate-n-butanol-water (2:1:3, v/v/v) was used to isolate and separate two C-glycosylflavones from Patrinia villosa Juss, a traditional Chinese medicine. The separation produced 42.9 mg isovitexin and 20.1 mg isoorientin with purities of 99.3% and 98.5%, respectively as determined by high-performance liquid chromatography (HPLC) in one step elution from 250 mg crude extract, and identification was performed by MS, 1H NMR and 13C NMR. It is the first report of discovering isovitexin and isoorientin from the plant of Patrinia genus.

Apigenin↗

PubMed2005

[Studies on chemical constituents of Patrinia villosa Juss].

Nine compounds including n-dotriacontanoic acid (I), n-dotriacontanol (II), Palmic acid (III), oleanolic acid (IV) aurentiamide acetate (V), daucosterol (VI), beta-sitosterol (VII), 7beta-hydroxysitosterol (VIII) and stigmasterol (IX) were isolated from petroleum ether and chloroform extract of Patrinia villosa Juss. Among them, compounds I, II, V, VIII were obtained from the plant of Patrinia for the first time and compounds VI, VII ,IX were separated from Patrinia villosa Juss for the first time.

Acetates↗

PubMed2005

[Preparation of soybean isoflavone aglycones by reversed-phase high performance liquid chromatography from Semen Sojae Praeparatum].

OBJECTIVE: An efficient method for the isolation of isoflavone aglycones from Semen Sojae Praeparatum was developed. METHODS: The crude isoflavones were extracted by 75% aqueous ethanol and primarily purified by 1300 macroporous resin,and then the fractions containing daidzein, glycitein and genistein were obtained and subjected to preparative HPLC for the isolation of target components. RESULTS: Daidzein, glycitein and genistein were obtained with purities of over 99%, etermined by analytical HPLC. CONCLUSION: This technique is simple and suitable for the isolation of isoflavone aglycones from Semen Sojae Praeparatum.

Chromatography, High Pressure Liquid↗