Fig. 3

Results of PCA on the quantitative parameters from the power–time curves of drug-resistant E. coli growth affected by six samples from the leaves of D. dao. a 3D PCA score plot counted from the supervised PLS-DA where each point corresponds to a single concentration level of the samples, showing clear purple sphere clustering of the concentration points from the S6 sample. b Loadings plot indicated the contribution of the original variables (parameters) to the strength of the first two principal components PC1 and PC2, so that the main parameter(s) of the effect evaluation can be found and marked with a circle