A Simplified and Solvent-Reduced HPLC-UV/Vis Method for the Simultaneous Determination of Major Marker Compounds in Rhodiola rosea L.

Rhodiola rosea L. is traditionally used to relieve stress-related symptoms and has been investigated for its potential effects on depression and anxiety. The present study developed and validated a solvent-reduced HPLC-UV/Vis method for the determination of characteristic secondary metabolites in R. rosea. To minimize solvent consumption and eliminate methanol from sample preparation, extraction with 40% (v/v) ethanol was combined with a simplified chromatographic protocol. Extracts were analyzed by HPLC-UV/Vis for the target analytes salidroside, tyrosol, rosarin, rosavin, and rosin. Chromatographic separation was achieved within 35 min using a water–acetonitrile gradient at a flow rate of 0.8 mL min−1. Compared with the reference method described by Ganzera et al., the optimized protocol reduced the total analysis time from 44 to 35 min and eliminated the post-run methanol washing step. Method validation yielded analyte-specific recoveries ranging from 102 ± 3% to 114 ± 4% and relative standard deviations from 0.5% to 8.0%. The limits of quantification were 0.497, 0.302, 0.477, 0.148, and 0.189 µg mL−1 for salidroside, tyrosol, rosarin, rosavin, and rosin, respectively. Quantification was performed by external standard calibration. The developed method offers a simplified, solvent-reduced approach for the quantitative determination of major R. rosea marker compounds, thereby reducing both analysis time and solvent consumption.