[Simultaneous determination of multi-components in Chinese herbal medicine with UV spectrometry by virtual components-artificial neural network].

In the present paper, the simultaneous determination of multi-components in Chinese herbal medicine was performed by artificial neural network-UV spectrometry. The interference of other components was eliminated by self-revising and self-simulation of the virtual component. The double ANN including training and simulation network was established, and the capabilities of self-recognition and self-studying were improved. Therefore, the prediction accuracy of multicomponent content was improved greatly in the complicated Chinese herbal medicine system. The contents of aesculin and aesculetin, which were extracted from 21 Cortex Fraxinis, were predicted. Comparing the results with those of HPLC, the prediction accuracy was more than 90% within the relative errors less than 10%. The measurement precisions of aesculin and aesculetin were 0. 37% and 1. 5% respectively.

[Determination of 20 (S)-ginsengnoside Rh2 in the alkali-hydrolysis product of saponins from leaves of Panax qinquefolium by RP-HPLC].

OBJECTIVE: To determine 20(S)-ginsengnoside Rh2 in the hydrolysis product of saponins from leaves of Panax qinquefolium. METHOD: The separation was performed on ZORBAX EXEND C18 column (4.6 mm x 250 mm, 5 microm), eluted with methanol and water (85:15) as mobile phase with the rate of 1.2 mL x min(-1) at 25 degrees C, the wavelength for measurement was 203 nm. RESULT: The calibration curve was linear in the range of 0.5-25 microg for 20(S)-ginsengnoside Rh2(r = 0.9999, n = 7). The average recovery was 99.7% (RSD= 1.0%). CONCLUSION: This method is simple, accurate, reliable and reproducible. The result shows that the transform ratio of 20(S)-ginsengnoside Rh2 is high by this hydrolysis method.

Separation and identification of Aconitum alkaloids and their metabolites in human urine.

To study the safety of Aconitum medicinal herbs in clinic and identify Aconitum alkaloids poisoning in forensic medicine, Aconitum alkaloids and their metabolites were separated and identified in human urine by liquid chromatography-electrospray ionization-multi-stage mass spectrometry (LC-ESI-MS(n)) and chemical pathway of metabolism was investigated. The alkaloids and their metabolites in the urine sample were extracted with solid-phase cartridges and separated by HPLC with acetonitrile-water-formic acid (40:60:0.5) mobile phase. Structures of five metabolites and three parent Aconitum alkaloids were identified with multi-stage mass spectrometry data through comparison with authentic substances as aconitine (M(1)), mesaconitine (M(2)), hypaconitine (M(3)), benzoylaconine (M(4)), benzoylmesaconine (M(5)), benzoylhypaconine (M(6)), 16-O-demethylaconitine (M(7)) and 16-O-demethylhypaconitine (M(8)), respectively. Among them, M(8) was identified and reported for the first time. Metabolic pathways of Aconitum alkaloids in human body were proposed.