RESUMO
Euphorbia lathyris (Caper spurge) is a toxic and potent Chinese materia medica (T/PCMM).This study sought a method for identifying five diterpenoids (Euphorbia factors L1-L3,L7a and L8) with the spectra of UV and mass,quantifying three diterpenoids L1,L2,and L8 in crude extracts of unprocessed and processed E.lathyris seeds by liquid chromatography/electrospray ionization mass spectrometry (LC-ESI-MS).The analysis was achieved on an Agilent Eclipse XDB-C18 column (4.6 mm × 150 mm i.d.,5 μm) with an isocratic elution with a mobile phase consisting of water and acetonitrile at a flow rate of 0.25 mL/min at column temperature of 30 ℃ and UV detection was set at 272 nm.An ESI source was used with a positive ionization mode.The calibration curve was linear in the ranges of 9.9-79 μg/mL for Euphorbia factor L1,3.8-30.5 μg/mL for Euphorbia factor L2,and 1.0-20.6 μg/mL for Euphorbia factor L8.The average recoveries (n=6) of three diterpenoids were 98.39％,91.10％ and 96.94％,respectively,with RSD of 2.5％,2.4％ and 2.1％,respectively.The contents of the three diterpenoids in processed E.lathyris seeds were 3.435,1.367 and 0.286 mg/g,respectively,which decreased more sharply than those in unprocessed E.lathyris seeds which were 4.915,1.944 and 0.425 mg/g,respectively.The method is simple,accurate,reliable and reproducible,and it can be applied to control the quality of unprocessed and processed E.lathyris seeds.
RESUMO
A method was established for identifying the chemical components of a traditional Chinese medicinal formula Baihe Zhimu Tang and its single herbs by combining high performance liquid chromatography and electrospray ionization mass spectrometry(HPLC-ESI-MS). The molecular ions of compounds in both negative and positive modes were observed for molecule mass information, and the potential structures were identified by attentive studying on the mass spectra of compounds and comparing with Reference data and some of standards. The results show that in MS detection, saponins in Baihe Zhimu Tang and its single herbs are easily to become positive ions in the electrospray ionization procedure, and they have strong responses, but the mass spectrometric signals of flavonoids and phenolic glucosides are week. 38 compounds in Baihe Zhimu Tang including 3 flavonoids, 4 phenolic glucosides and 31 saponins were identified through analyzing and comparing the total ion chromatograms(TIC) and mass spectra of Baihe Zhimu Tang and its single herbs. This method has the advantages of simple operation, rapid measurement and it is a powerful tool for identification of chemical components in Baihe Zhimu Tang.