[Enrichment of saponins in Radix et Rhizoma Cynanchi Atrati with macroporous resin].

OBJECTIVE: To develop an approach to the determination of saponins in Radix Cynanchi Atrati, and to optimize the parameters for purified the preparation of total saponins by macroporous resin column chromatography. METHOD: Using cynanversicoside A as a reference, the determination of saponins was performed; according to the elution rate and the purity of the products, the preparation performance of total saponins by macroporous resin was investigated, and its parameters were optimized. RESULT: The saponins in Radix Cynanchi Atrati were successfully determined at 518 nm by vanillin-perchloric acid as spray reagent. The macroporous resin HP-20 showed static absorption ratio of 59. 3 mg x g(-1); the 70% ethanol extraction of Radix Cynanchi Atrati was eluted from column of macroporous resin HP-20 by water and 30% ethanol, and the saponins were concentrated in 90% ethanol solution. The content of saponin part eluted from HP-20 column was 77.62%. CONCLUSION: The proposed approach allows convenient and efficient preparation and purification of saponin in Radix Cynanchi Atrati.

Quantitative determination of the anticancer agent tubeimoside I in rat plasma by liquid chromatography coupled with mass spectrometry.

Tubeimoside I is an important component isolated from Bolbostemma paniculatum. Tubeimoside I has been demonstrated to possess many pharmacological activities, including anti-inflammatory, antitumor, and antitumor-promoting effects. The purpose of the present study was to examine in vivo pharmacokinetics and bioavailability of tubeimoside I in rats by using a liquid chromatography coupled with mass spectrometry quantitative detection method (LC/MS). The plasma samples were deproteinated, evaporated and reconstituted in 100 microl methanol prior to analysis. The separation was performed by Waters Symmetry C18 reversed-phase column (3.5 microm, 150 mm x 2.1mm, Waters Inc., USA) and a SB-C18 guard column (5 microm, 20 mm x 4.0mm). The mobile phase was a mixture of acetonitrile and water containing 5 microM NaAc (60:40, v/v). The method was validated within the concentration range 20-5000 ng/ml, and the calibration curves were linear with correlation coefficients >0.999. The lowest limit of quantitation (LLOQ) for tubeimoside I was 20 ng/ml in 0.1 ml rat plasma. The intra-assay accuracy and precision ranged from 92.4 to 104.9% and from 5.8 to 10.5%, respectively, while inter-assay accuracy and precision ranged from 94.2 to 95.0% and from 5.1 to 8.8%, respectively. The method was further applied to assess pharmacokinetics and oral bioavailability of tubeimoside I after intravenous and oral administration to rats. The oral bioavailability of tubeimoside I is only 0.23%, which indicates that tubeimoside I has poor absorption or undergoes acid-induced degradation. Practical utility of this new LC/MS method was confirmed in pilot pharmacokinetic studies in rats following both intravenous and oral administration.

Benzophenanthridine alkaloids from Zanthoxylum nitidum (Roxb.) DC, and their analgesic and anti-inflammatory activities.

Seven benzophenanthridine alkaloids, 1-7, were isolated from the roots of Zanthoxylum nitidum. Among them, two novel alkaloids, named (R)-8-[(R)-1-hydroxyethyl]dihydrochelerythrine (1) and 8-methoxynorchelerythrine (2), were structurally identified as new compounds on the basis of the spectroscopic analysis. Bioactivity evaluation showed that nitidine (3), dihydrochelerythrine (4), oxyavicine (5), 8-methoxychelerythrine (6), and 8-hydroxydihydrochelerythrine (7) exhibit comparable analgesic and anti-inflammatory effects as hydrocortisone.

Inhibitory effects of ligustilide and butylidenephthalide on bFGF-stimulated proliferation of rat smooth muscle cells.

AIM: To investigate the bio-affinities of ligustilide and butylidenephthalide to rat aortic smooth muscle cells and the inhibitory effects of them on bFGF-stimulated proliferation of rat vascular smooth muscle cell (VSMC). METHODS: VSMCs were cultured from rat aorta pectoralis and identified by an immunohistochemical method. The bio-affinities between solute (ligustilide or butylidenephthalide) and cell membrane were measured by rat aortic cell membrane chromatography (CMC). The inhibitory effects of ligustilide and butylidenephthalide on bFGF-stimulated VSMC proliferation were evaluated by MIT colorimetric method. RESULTS: Both ligustilide and butylidenephthalide had selective affinities to rat aortic smooth muscle cell as the same as verapamil, one of the calcium ion antagonists. They could potently inhibit the bFGF-stimulated VSMC proliferation at the concentrations of 5.5 and 11.1 micromol x L(-1), separately (P < 0.05), but had no effects on the normal VSMC growth. CONCLUSION: Both ligustilide and butylidenephthalide can inhibit the abnormal proliferation of VSMC induced by bFGF.

[Chemical constituents in root of Zanthoxylum nitidum].

OBJECTIVE: To study the chemical constituents of Zanthoxylum nitidum. METHOD: Column chromatography on Silica gel and Sephadex LH - 20, and recrystallization were applied for the isolation and purification of the constituents. The structures were elucidated on the basis of spectral analysis, chemical evidences and by comparison with the data reported in literature. RESULT: From the CHCl3 fraction and n-butanol fraction of the EtOH extract of the roots of Z. nitidum, 10 compounds were isolated and identified as 2, 4-dihydroxypyrimidine (1), syringic acid (2) , 2, 6-dimethoxy-1, 4-benzoquinone (3) , 4-hydroxybenzoic acid (4), ethylparaben (5), (Z)-3-(2, 3, 4-trimethoxyphenyl) acrylic acid (6), 5, 6, 7-trimethoxycoumarin (7), stigmast-9 (11) -en-3-ol (8), daucosterol (9), beta-sitosterol (10). CONCLUSION: Compounds 1-9 were isolated and identified from the roots of Z. nitidum for the first time. Furthermore, we note here the first isolation of compound 6 as a natural product.

Screening, analysis and in vitro vasodilatation of effective components from Ligusticum Chuanxiong.

Effective components, ligustilide and butylidenephthalide, from Ligusticum Chuanxiong (Ligusticum wallichii Franchat, Umbelliferae) were screened and identified by using a cell membrane chromatography (CMC) and a gas chromatography/mass spectrometry (GC/MS). The components showed the effects of inhibiting vasoconstriction in vitro on rat abdominal aorta segments. The screening procedure was performed in a rat artery CMC column (50 mm x 2.0 mm I.D.) with a sodium phosphate buffer (pH 7.4) as mobile phase at 37 degrees C. The identification was accomplished by a DB-5MS 30 m capillary column (0.25 mm I.D., 0.25 microm film thickness) with helium as carrier gas operating under program control temperature and electron impact ionization mass spectrometer in a scan mode. Results demonstrated that ligustilide and butylidenephthalide can act on rat artery cell membrane similar to verapamil in CMC system. They significantly inhibited the vasoconstrictions induced by norepinephrine bitartrate (NE) and calcium chloride (CaCl2). The relaxing effect of ligustilide on the NE- and CaCl2-induced constrictions is more potent than that of butylidenephthalide. Ligustilide and butylidenephthalide seem to be the two main effective components of Ligusticum Chuanxiong as a traditional Chinese medicine for treating blood vessel diseases.