[Effect of phenformin hydrochloride on pharmacokinetics of puerarin in rats].

OBJECTIVE: To study the effect of phenformin hydrochloride that may be illegally added in traditional Chinese medicine preparations on the pharmacokinetics of puerarin in rats. METHOD: Rats were randomly divided into the single pueraria group and the phenformin hydrochloride combined with pueraria group. After oral administration in the two groups, their bloods were sampled at different time points to determine the drug concentration of puerarin in rat blood and calculate pharmacokinetic parameters. RESULT: After oral administration with pueraria extracts and phenformin hydrochloride combined with pueraria extracts, the two groups showed main pharmacokinetic parameters as follows: Cmax were (2.39 +/- 1.01), (1.03 +/- 0.35) mg x L(-1), respectively; Tmax were (0.50 +/- 0.09), (1.5 +/- 0.5) h, respectively; Ke were (0.153 +/- 0.028), (0.172 +/- 0.042) h(-1), respectively; t(1/2) were (4.65 +/- 0.86), (4.20 +/- 0.81) h, respectively; AUC(0-t), were (5.73 +/- 2.60), (5.45 +/- 1.81) mg x h x L(-1), respectively; AUC(0-infinity) were (6.72 +/- 2.89), (6.26 +/- 1.88) mg x h x L(-1), respectively. Compared with the single puerarin group, the Cmax was significantly decreased (P < 0.05) and the Tmax was markedly longer (P < 0.01) than the hydrochloride combined with pueraria group. CONCLUSION: Phenformin hydrochloride can slow down the absorption process of puerarin and change the pharmacokinetic process of puerarin to some extent.

[Studies on chemical constituents of the extract of Lonicera japonica].

OBJECTIVE: To isolate and elucidate the structure of the constituents of the extract of Lonicera japonica. METHODS: The compounds were isolated and repeatedly purified on TLC, silica gel column chromatography, and gel column chromatography. The structures were elucidated by physico-chemical properties, MS and NMR. RESULTS: Seven compounds were obtained and elucidated as luteolin (I), luteoloside (II), quercetin (III), quercetin-3-0-beta-D-glucoside (IV), quercetin-7-0-beta-D-glucoside (V), rutin (VI), chlorogenic acid (VII). CONCLUSION: Compound V is isolated from this genus for the first time.

[Fingerprint analysis of composite Folii Isatidis injection by HPLC].

OBJECTIVE: To develop the chromatographic fingerprints of composite Folii Isatidis injection by HPLC. METHOD: The separation was performed on a Diamonsil C18 column with a mobile phase consisting of methanol-water-phosphoric acid as gradient eluent at the flow rate of 1.0 mL x min(-1). The UV detection was set at 254 nm. RESULT: A standard HPLC fingerprint procedure was developed for composite Folii Isatidis injection, with 20 common peaks and a similarity threshold of 9.0 established. CONCLUSION: This method was accurate, repeatable and useful for the quality control of composite Folii Isatidis injection.

[Chemical constituents from herb of Epimedium brevicornum].

OBJECTIVE: To investigate the chemical constituents of Epimedium brevicornum. METHOD: The chemical constituents were isolated by using silica gel column chromatography and preparative TLC. The structures were identified on the basis of physical-chemical constants and spectral data. RESULT: Five compounds were isolated and identified as hyperoside, icariin, epimedin B, epimedin C, inositol. CONCLUSION: Compound I and III - V were isolated from the plant for the first time.

[Determination of adenosine, rutin and quercetin in Carthamus tinctorius by HPCE].

AIM: To develop a method for determination of adenosine, rutin and quercetin in Carthamus tinctorius L. by high performance capillary electrophoresis(HPCE). METHODS: A fused silica capillary (66.5 cm x 50 microns ID, an effective length of 58 cm) was used. The running buffer composed of 50 mmol.L-1 borax (pH 9.7) containing 18% methanol. The applied voltage was 24 kV and the capillary temperature was 20 degrees C. The detection wavelength was 210 nm. Rifampicin was used as internal standard. RESULTS: A good linearity between peak area ratio of the common peak to the internal standard and the concentration was found in the range of 10-160 mg.L-1 for adenosine, 100-2,000 mg.L-1 for rutin and 100-1,600 mg.L-1 for quercetin (r > 0.998). The average recoveries were 98.5%-100.5%, 96.9%-99.5% and 99.1%-99.5% for adenosine, rutin and quercetin, respectively. The relative standard deviation was less than 6.5% (n = 5). CONCLUSION: The method is simple, rapid and with satisfactory recoveries and good reproducibilities. It can be used to control the quality of Carthamus tinctorius.

[Preparation and simultaneous determination of corynoline and acetylcorynoline in the herb of Corydalis bungeana].

OBJECTIVE: To isolate and purify corynoline and acetylcorynoline from Corydalis bungeana and develop a reversed-phase HPLC method of determining the two components in C. bungeana. METHOD: Alkaloids were isolated from the ethanolic extract with column gel chromatography, and identified on the basis of spectral analysis (UV, 1H-NMR, 13C-NMR) and physicochemical properties. For quantitative analysis of the two components, samples were separated on an ODS column with mobile phase of methanol-15 mmol.L-1 potassium dihydrogen phosphate/potassium phosphate dibasic (pH 6.70, 70:30). The flow rate was 0.8 mL.min-1, and the detection was set at 289 nm. RESULT: The purity was 99.5% and 99.1% for corynoline and acetylcorynoline respectively. The calibration curves were linear in the range of 6.9-110.4 mg.L-1 corynoline and 8.7-139.5 mg.L-1 acetylcorynoline. The RSD was 2.1% and 2.7%, and the average recovery was 97.3% and 97.2% respectively. CONCLUSION: The method of isolating and purifying corynoline and acetylcorynoline from Corydalis bungeana and the HPLC method of simultaneous determination of the two components have been developed. The HPLC method is simple, easy to perform and applicable to the content determination of corynoline and acetylcorynoline in C. bungeana of various origins.

[Determination of trigonelline in Trigonella foenum-graecum by HPLC].

OBJECTIVE: A HPLC method is established to determine the content of trigonelline in Trigonella foenum-graecum. METHOD: The medicinal material was extracted by petholeum ether-ethanol. Asahipak NH2P-50 column was used, mobilephase consisted of acetonitrile-water(75:25) and detection wavelength was set at UV 265 nm. RESULT: The standard curve was linear in the range of 3.68-73.60 micrograms.mL-1 with the correlation coefficient of 0.9999. The average recovery rate and RSD were 97.4% and 1.83% (n = 6) respectively. CONCLUSION: It provides scientific indexes for quality control of T. foenum-graecum.

[HPLC determination of two flavonoid compounds in Psoralea corylifolia].

OBJECTIVE: To determine two flavonoid compounds in Psoralea corylifolia L. (PC) simultaneously with HPLC method. METHOD: Bavachin and corylin isolated from PC and purified in our laboratory were used as the reference compounds. The HPLC separation was carried out on an Techsphere ODS column using mobile phase consisting of a mixture of methanol and 20 mmol.L-1 ammonium acetate buffer pH 4.0 (67:33), and the UV detection wavelength was 240 nm. RESULT: Simultaneous determination of bavachin and corylin was achieved. The linear range was 1.25-20 micrograms.mL-1 for both bavachin and corylin. The average recovery of bavachin and corylin was 94.9% and 96.2%, and RSD was 3.1% and 3.6% respectively. CONCLUSION: This is the first report on simultaneous determination of bavachin and corylin in PC with satisfactory accuracy and reproducibility.