Principal component analysis (PCA): R. toruloides versus S. cerevisiae. PCA two-dimensional score plots of R. toruloides and S. cerevisiae intact cells, and of the selected fatty acid standards, performed between 3,050 and 2,800 cm-1. PC1-PC2 (A) and PC1-PC3 (B) are reported. PCA has been performed on the raw Fourier transform infrared (FTIR) spectra. For clarity, only the cluster centroid has been shown for the yeast strain data, which represents the data corresponding to three independent experiments, each one consisting of at least ten FTIR spectra.