||The profiling data files recorded in the MassLynx format (raw) were converted to the NetCDF format using the DataBridge function of MassLynx 4.1. From the set of NetCDF data files, the data matrix was generated using the MetAlign software(De Vos et al., 2007). By using this procedure, the data matrixes with unit mass data were generated. The data matrices were processed using in-house software written in Perl/Tk. The original peak intensity values were divided with that of the internal standards (lidocaine at m/z 235 [M + H]+ and (-)-camphor-10-sulfonic acid at m/z 231 [M - H]- for the positive and negative ion modes, respectively) determined in the same samples to normalize the peak intensity values among the metabolic profile data.