Da Huang (Zhi)

Rhei Radix et Rhizoma (Processed with Wine) Stir-bake the slices as described under the method for stir-baking with wine (0213) until dry. Description Similar to the slices of Rhei Radix et Rhizoma. Externally dark brownish-yellow, some with slight scorched patches. Odour slightly wine-like and aromatic. Identification As required for the crude drug. Rhaponticin As required for the crude drug. Water Not more than 13.0%. Total Ash As required for the crude drug. Extractives As required for the crude drug. Assay Total Anthraquinone As required for the crude drug. Free Anthraquinone Not less than 0.50%. Rhei Radix et Rhizoma (Prepared) Stew or steam the pieces as described under the method for stewing or steaming with wine (0213) until thoroughly darkened. Description Irregular pieces. Externally black. Radial striations indistinct on the fractured surface. Texture hard. Odour slightly aromatic. Identification As required for the crude drug. Rhaponticin As required for the crude drug. Water Not more than 13.0%. Total Ash As required for the crude drug. Extractives As required for the crude drug. Assay Total Anthraquinone As required for the crude drug. Free Anthraquinone Not less than 0.50%. Rhei Radix et Rhizoma (Carbonized) Stir-bake the slices as described under the method for carbonizing by stir-baking (0213) until the outer surface is charred and the interior becomes dark brown. Description Similar to the prepared slices. Externally charred black. Interior dark brown to charred brown. Odour charred and aromatic. Identification Identification (2) and (3): As required for the crude drug. Rhaponticin As required for the crude drug. Water As required for the crude drug. Total Ash As required for the crude drug. Extractives As required for the crude drug. Assay Total Anthraquinone Not less than 0.90%. Free Anthraquinone Not less than 0.50%.