Simultaneous determination of ten characteristic antioxidant compounds for inhibiting cancer cell proliferation in Prunella vulgaris L. from different regions using HPLC-UV coupled with MS identification

A sensitive and reliable HPLC-UV method coupled with MS identification was developed for the first time to simultaneously determine the ability of 10 compounds, including caffeic acid, hesperidin, rosmarinic acid, quercetin, luteolin, oleanolic acid 3-O-monoglucuronide, rhein, corosolic acid, oleanolic acid and ursolic acid, to inhibit cancer cell proliferation and their antioxidant activities in the spikes of Prunella vulgaris L. (PV). HPLC analysis of these compounds was performed using a reversed-phase Alltima C-18 column (150 mm x 4.6 mm, 5 mu m). The mobile phase consisted of acetonitrile (A) and 0.1% glacial acetic acid solution (B) with gradient elution; the column temperature was maintained at 30 degrees C and the detection wavelength was set to 215 nm. The flow rate was 1.0 ml min(-1) for 0-60 min and was then changed to 0.4 ml min(-1) between 60 min and 105 min. The enhanced method has good linear regression (R-2 > 0.9994), good precision and accuracy (RSD < 3%). The recoveries of the ten compounds ranged from 95.6-103.8% (RSD < 5%). This HPLC-UV method coupled with MS identification was successfully applied to quantify these anti-tumor and antioxidant compounds in 14 batches of PV, collected from different cultivation regions. Based on the content of these compounds, these PV samples were classified using hierarchical clustering analysis (HCA). Our results demonstrated that established HPLC-UV coupled with MS identification was a useful and reliable tool for quality control of PV.