Fig. 2From: Comparative analysis of four terpenoids in root and cortex of Tripterygium wilfordii Radix by different drying methodsHPLC chromatograms of reference substance (a) and Tripterygium wilfordii Radix samples (b) (1. Triptolide; 2. Triptophenolide; 3. Demethylzeylasteral; 4. Celastrol)Back to article page