Compositional data analysis method based on NMR metabolomics: An application to evaluate Chinese materia medica / 中草药

ABSTRACT

The peak area normalization is often needed as the preprocessing of NMR metabolomic data and the relative ratio of normalized data is the same as that of peak area in original spectrum, so the normalized data can reflect the relative information of peak area. This research selects the normalized data of the peak area for each sample to analyze, compositional data is the nonnegative vector containing only the relative information. Therefore the normalized data can be considered as compositional data. This paper used compositional data analysis based on NMR metabolomics to study the homogeneity for each group's samples, identify the characteristic metabolites which contribute the classification of different groups, and make the discriminate analysis for the given new sample in the evaluation of Chinese materia medica. In the case the analysis of quality evaluation on Astragali Radix, it can be seen from the results that the proposed method is feasible.