| A new method was used for the rapid screening and identification of free radical scavengers in the extracts of Salvia miltiorrhiza Bunge and Salvia prattiiHemsl., and the determination of the content of the analytes in the samples based on HPLC-DAD-ESI/MSn-DPPH was developed.The three compounds were identified to be caffeic acid, salviaflaside and rosmarinic through comprehensive analysis of HPLC spectra, MS spectra and literature data.The extraction effects of the hot reflux,ultrasonic assisted extraction and accelerated solvent extraction(ASE) were compared and the chromatographic conditions were optimized.Under the optimized conditions,three compounds could be effectively separated.Good linear relationships were obtained for three compounds in the concentration range of 1.7-35.3 μg/mL,with correlation coefficients of 0.999 5-0.999 8.The detection limits were in the range of 0.05-1.85 μg/mL,and the quantitation limits were in the range of 0.18-6.16 μg/mL.The average recoveries of three compounds were between 96.6% and 97.2%,with relative standard deviations of 1.1%-1.3%.The method was applied in the determination of three compounds contents in Salvia miltiorrhiza Bunge and Salvia prattiiHemsl.,with caffeic acid:0.303,0.254 mg/g; salviaflaside:1.019,1.401 mg/g;rosmarinic:17.279,8.104 mg/g.The method is convenient,fast,accurate and reproducibile.Otherwise,it gives a powerful tool for the rapid screening and identification of free radical scavenging compounds in complex natural products. |