Quality control over different processed products of Polygalae Radix based on plant metabolomics Quality control over different processed products of Polygalae Radix based on plant metabolomics Study on quality assessment of Polygalae Radix based on HPLC-DAD fingerprint Research progress on Polygalae Radix Correlation between environmental factors and liposoluble and hydrophilic constituents of Polygalae Radix Simultaneous analysis on index compounds and fingerprint analysis on Polygalae Radix by ultra performance liquid chromatography