Similarity and difference in chemical profile and antioxidant activity between Chinese materia medica decoction pieces and their aqueous granules : Danggui, Danshen and Sanqi

In recent years, Chinese materia medica (CMM) granules have become a convenient way of dispensing Chinese medicinal materials; however methodology for their quality control is lacking to support their increasing use in TCM practice. At the Braga AGM in July 2011, the GPTCM Consortium1 members raised these issues, which were further discussed at the Joint Workshop of the Working Packages (WP1, WP3 and WP7) in Strasbourg in September. In a systematic review, WP6 members recommended that more rigorous research comparing granules with CMM decoction pieces is required. To address this concern, our research team applied chromatography (TLC, UPLC-PDA), chemometric analysis and antioxidant assays (ABTS, FRAP and DPPH) to compare the chemical profiles and anti-oxidant activity of the three popular CMM decoction pieces and their granules: Angelicae Sinensis Radix (Danggui), Salviae Miltiorrhizae Radix et Rhizoma (Danshen) and Notoginseng Radix et Rhizoma (Sanqi). Decoction pieces were extracted in water, freeze-dried and then extracted with methanol. The granules were extracted in methanol to remove the excipients. Similarity between samples was performed by hierarchical agglomerative clustering analysis (HCA) and principle component analysis (PCA). Aqueous extraction revealed polar compounds in the decoction pieces. Non-polar components were detected with more variation in the granule extracts, which raised questions regarding production processes among manufacturers. No significant difference was detected between the antioxidant activities of similar clusters, although higher values were observed from decoction pieces. Thus, practitioners should be aware of the differences among the products in order to support their dosage regimes.