Multi-level fingerprint and immune activity evaluation of polysaccharides from Rhodiola rosea L

To establish the quality control method of Rhodiola rosea L., the multi-level fingerprinting profile was established. The quality evaluation of Rhodiola rosea L. was evaluated based on the following information: polysaccharide content in herbs (2.86-4.51 %), thirteen infrared absorption peaks (3391.25 cm^-1, 2934.03 cm^-1, 1747.47 cm^-1, 1618.67 cm^-1, 1445.12 cm^-1, 1374.16 cm^-1, 1357.16 cm^-1, 1237.94 cm^-1, 1102.37 cm^-1, 1017.50 cm^-1, 762.27 cm^-1, 631.88 cm^-1 and 528.77 cm^-1), seven monosaccharides (Mannose, Rhamnose, Glucuronic acid, Glucose, Galactose, Xylose, Arabinose), and two molecular weight segments Mw1 (7.12 × 10⁵-1.31 × 10⁶ Da) and Mw2 (6.04 × 10³-6.92 × 10³ Da). The results of chemometric analysis found that the infrared absorption peaks of 762.27 cm^-1, the monosaccharides of Man and Xyl, and the molecular weight of Mw1 were the key markers in differentiating the origin of Rhodiola rosea L. The spectrum-effect relationship showed that Rhodiola rosea L. polysaccharides (RRP) with a higher infrared absorption peak at 1618.67 cm^-1, higher Xyl, and higher Mw1 displayed higher immune activity. In conclusion, this study determined the RRP content in herbs, established a polysaccharide-based quality control method for Rhodiola rosea L., and investigated the connection between fingerprints and in vitro immune activity. All of this study can provide more theoretical support for the authentication and quality control of Rhodiola rosea L.