Chemical profiling approach to evaluate the influence of traditional and simplified decoction methods on the holistic quality of Da-Huang-Xiao-Shi decoction using high-performance liquid chromatography coupled with diode-array detection and time-of-flight mass spectrometry.

Da-Huang-Xiao-Shi decoction, consisting of Rheum officinale Baill, Mirabilitum, Phellodendron amurense Rupr. and Gardenia jasminoides Ellis, is a traditional Chinese medicine used for the treatment of jaundice. As described in "Jin Kui Yao Lue", a traditional multistep decoction of Da-Huang-Xiao-Shi decoction was required while simplified one-step decoction was used in recent repsorts. To investigate the chemical difference between the decoctions obtained by the traditional and simplified preparations, a sensitive and reliable approach of high-performance liquid chromatography coupled with diode-array detection and electrospray ionization time-of-flight mass spectrometry was established. As a result, a total of 105 compounds were detected and identified. Analysis of the chromatogram profiles of the two decoctions showed that many compounds in the decoction of simplified preparation had changed obviously compared with those in traditional preparation. The changes of constituents would be bound to cause the differences in the therapeutic effects of the two decoctions. The present study demonstrated that certain preparation methods significantly affect the holistic quality of traditional Chinese medicines and the use of a suitable preparation method is crucial for these medicines to produce special clinical curative effect. This research results elucidated the scientific basis of traditional preparation methods in Chinese medicines.