Fig. 6.

PC1 versus PC2 PCA scores plots calculated from the 1D proton spectra of a population of human urine samples with two subpopulations. Repeat of calculations presented in Fig. 5, but with spectral features from urea, ethanol, hippurate, and creatinine excluded. Yellow circles “low taurine” subpopulation (0–1 mM taurine). Blue diamonds “high taurine” subpopulation (4–5 mM taurine). a Calculation based on data matrix of bucket integrated 1D proton spectra. b Repeat of calculation from A, but with taurine 1D TOCSY read peak integrals substituted for taurine 1D proton bucket integrals