[Preliminary study on chemical changes in the decocting process of radix et rhizoma Rhei].

OBJECTIVE: To understand the chemical changes in the decocting process of Radix et Rhizoma Rhei. METHOD: Comparing the contents of many kinds of anthraquinones in the crude drug, decoction and drug sediments of Radix et Rhizoma Rhei by HPLC. RESULT: The contents of combined and free anthraquinones changed after the crude drug was decocted. CONCLUSION: These changes may be related to the hydrolysis of combined anthraquinones, the decomposition of free anthraquinones, and the inter-transition among anthraquinones.