Fig. 3

PCA biplot (loading and score plot) of Sanqi raw herb and granule extracts analysed by (a) TLC and (b) UPLC. a From the TLC biplot, R1 to R4 demonstrated a higher amount of the compounds (Cluster 1), especially R4 (highest amount of Rd and Rg2). R5 and R6 were closely distributed with the granules (Cluster 2). b For UPLC, Group 1 containing the raw herbs, G7 and G12 which possessed higher amounts of the five compounds, whilst Group 2 contained the rest of the granules