Figure 2

Principal component analysis (PCA) and hierarchical cluster analysis (HCA) of E. longifolia commercial preparations NMR dataset. (A) Score plot of PC1 vs. PC2, complete segregation of the authentic samples from the commercial products. (B) Loading plot for PC1 and PC2 showing signals of fatty acids (δ 0.88, 1.28 ppm) and 13,21-dihydroeurycomanone (δ 1.24 ppm) as the major signals contributing to samples discrimination. (C) HCA of NMR dataset shows two main cluster: cluster (a) for the authentic samples and cluster (b) for the commercial product specimens.