Identification of Angelica oil as a suppressor for the biological properties of Danggui Buxue tang: a Chinese herbal decoction composes of Astragali Radix and Angelica Sinensis Radix

Ethnopharmacological relevance: Danggui Buxue Tang (DBT), a Chinese herbal decoction commonly used in treating women's ailments, contains two herbs: Angelica Sinensis Radix (ASR) and Astragali Radix (AR). Traditionally, ASR had to be pre-treated with yellow wine before the herbal preparation, which reduced the amount of volatile oil in water extract of ASR and DBT, and meanwhile the volatile oil-reduced DBT processed better bioactivities in cell cultures. The present study aimed to investigate the effect of volatile oil from ASR (Angelica oil) on the solubility of AR-derived ingredients and the biological properties of DBT. Materials and methods: To standardize Angelica oil, four marker chemicals in ASR were determined by GC-QQQ-MS/MS. Subsequently, fifteen gram of AR was boiled with different amounts of Angelica oil. The amounts of astragaloside IV, calycosin, formononetin, total polysaccharides, total saponins and total flavonoids, all derived from AR, were extracted and determined by HPLC-UV/ELSD. To reveal the effect of Angelica oil on DBT functions, several cell assays related to the traditional functions of DBT were selected, including anti-platelet aggregation, induction of NO production, hematopoetic, estrogenic and osteogenic properties. Results: The inclusion of Angelica oil in AR during preparation significantly decreased the amount of AR-derived astragaloside IV, calycosin, formononetin, total saponins and total flavonoids in the final water extract. In parallel, an inclusion of Angelica oil caused a decrease of DBT's estrogenic and hematopoetic activities in cultured cells. Moreover, the Angelica oil decreased DBT-induced cell proliferation of cultured MG-63 and endothelial cells. Conclusions: The results indicated that Angelica oil was a negative regulator for DBT chemically and biologically, which supported the traditional practice of preparing DST by using the wine-treated ASR. (C) 2014 Elsevier Ireland Ltd. All rights reserved.