Abstract:

HPLC fingerprinting and quantification of gentiopicroside (GPS) and loganic acid (LA) in Gentianae Macrophyllae Radix (GMR) crude drugs were developed in this study. The samples were separated on Zorbax SB-C18 column (250 mm×4.6 mm, 5 μm) with a linear gradient of acetonitrile and 0.04% phosphoric acid. The HPLC flow rate was 1.0 mL/min and a UV absorption was measured at 230 nm. An orthogonal L9 (3⁴) test was applied for the optimization of sample extraction conditions, and an aliquot of GMR sample (g) was extracted with 15-fold of 50% ethanol (mL) for 30 min by sonication. Quantitative analysis showed that the content of GPS (14.05 mg/g-74.61 mg/g) in all samples was obviously higher than that of LA (1.13 mg/g-40.46 mg/g). Based on the content ratio of GPS over LA (1.8-11.4), samples originated from Gentiana macrophylla (with content ratio of GPS over LA ≤4.3) could be distinguished from those from G. dahurica and G. dahurica var. gracilipes (with content ratio of GPS over LA ≥4.8). The principle components analysis of the HPLC fingerprints showed that samples originated from G. macrophylla and G. dahurica (including G. dahurica var. gracilipes) could be divided into two groups. This established HPLC-DAD method could be efficiently used for the species identification and quality control of GMR crude drugs.

Key words: Gentianae Macrophyllae Radix, HPLC fingerprint, Gentiopicroside, Loganic acid, Principle components analysis