Fig. 1From: A LC–ESI–MS/MS analysis procedure coupled with solid phase extraction and MeOH extraction method for determination of pyrrolizidine alkaloids in Tussilago farfara and Lithospermi erythrorhzionChemical structures of 8 pyrrolizidine alkaloids contained with high content in Farfarae Flos and Lithospermi Radix used in the present studyBack to article page