Quality Assessment of Ojeok-San, a Traditional Herbal Formula, Using High-Performance Liquid Chromatography Combined with Chemometric Analysis

Figure 4

Biplot of the principal components (PC1 versus PC2) of the variables (the contents of the 19 marker compounds) with the objectives (OJS samples). The effect of the marker compounds on the distribution of OJS samples is shown by the red-colored arrows. PC1 and PC2 contributed to 43% and 14% of total variance, respectively. OJS01, Ojeok-san water extract from the laboratory; OJS02–OJS10, Ojeok-san granules from Korean manufacturers.