Chemical fingerprint and quantitative analysis of Salvia plebeia R.Br. by high-performance liquid chromatography.

To control the quality of Salvia plebeia R.Br., a simple and reliable method of high-performance liquid chromatography coupled with photodiode array detector (HPLC-DAD) was developed both for fingerprint analysis and quantitative determination of seven bioactive compounds, namely caffeic acid, luteolin-7-glucoside, nepetin-7-glucoside, homoplantaginin, luteolin, nepetin and hispidulin. In fingerprint analysis, twelve peaks were selected as characteristic peaks. In quantitative analysis, seven compounds showed good regression (R2>0.9995) within test ranges and the recovery of the method was in the range of 91.7-103.2%. The content ranges (mg/g) of seven compounds in the collected samples of S. plebeia were 0.80-1.67 (hispidulin), 2.18-5.75 (homoplantaginin), 0.52-1.22 (nepetin), 1.56-3.48 (nepetin-7-glucoside), 0.12-0.24 (luteolin), 0.97-2.22 (luteolin-7-glucoside) and 0.21-0.44 (caffeic acid), respectively. From the results obtained, the content of homoplantaginin was the highest. In addition, luteolin and luteolin-7-glucoside were isolated for the first time from S. plebeia.