RESUMO
Objective: To identify the main active compounds in the aqueous extract from the aerial parts of Lycopus lucidus by high performance liquid chromatography (HPLC)-electrospray (ESI)-time of flight tandem mass spectrometry (TOF-MS/MS). Methods: The aqueous extract from the aerial parts of L. lucidus was prepared using ultrasonic method; Chromatographic separation of the main active compounds was performed on a TC-C18 (250 mm × 4.6 mm, 5 μm) reverse phase column through gradient elution; All the compounds eluted from the column were detected under both positive and negative ionization modes. Each chromatographic peak was analyzed by quadrupole tandem mass spectrometry coupled with TOF. Results: Twenty two compounds were identified through the analysis of tandem mass spectrum and the information from reference substances, including amino acids, phenolic acids, terpenoids, flavonoids and flavonoid glycosides, sterols, and fatty acid. Conclusion: HPLC-ESI-TOF-MS/MS is capable of analyzing the main compounds in the aerial parts of L. lucidus using retention time, ultraviolet spectrum, current molecular weight, formula, and fragmenting information of daughter ions. It will probably become a reliable alternative for the rapid analyzing substantial foundation of Chinese materia medica.