Figure 2

Selected chromatograms showing the different peak types at well-defined masses obtained from the different data sets. Chromatograms derive from a) metabolite fingerprinting data set; b) lipidomics data set; c) central carbon metabolism data set. Peaks derived from default parameters are presented in the left chromatograms and peaks coming from optimized parameters are shown in the chromatograms on the right side, respectively. The peak area integrated by XCMS is colored red. The m/z range for the chromatogram was chosen from the respective minimum and maximum m/z values of the particular peak. Comparison of chromatograms a) clearly demonstrate that default peak width parameters were too small for the broad peaks, b) shows an example where the mass range used in the default settings was too wide and c) illustrate peaks where the default peak width parameters were too wide.