Dang gui Root. Macroscopic Characterization A H P NOMENCLATURE MACROSCOPIC IDENTIFICATION QUANTITATIVE STANDARDS. have a bumpy or gnarled surface.

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1 Dang gui Root NOMENCLATURE Common Name: Dang gui Botanical Nomenclature: Angelica sinensis (Oliv.) Diels Botanical Family: Part Used: Apiaceae Root MACROSCOPIC IDENTIFICATION Dang gui roots are harvested in late autumn or early winter from 2- to 3-year-old plants. They are sold dried in whole, sliced, or chopped form and may be found sulfured or unsulfured. The roots are divided into 3 portions: head, body, and tails (branch roots) (Figure 2). These may be sold separately and are considered to have different therapeutic properties. Sliced and pressed roots with tails (palm slices) are the form most commonly used by traditional Chinese medical practitioners; the whole bodies (scraped and sulfured) are the form most commonly sold in the American health food market and in Chinese grocery stores for use in soups; while the unprocessed roots (sometimes with tails removed) are most commonly sold to dietary supplement manufacturers. A. Whole root (quan dang gui) Surface view: Cylindrical, ~ cm long, branching at the lower end into 2-10 primary branch roots with the numerous finer roots typically removed; light golden brown to dark brown; longitudinally wrinkled with horizontal lenticels. Transverse section: Bark brown and thick, with some clefts and numerous secretory cavities appearing as brown dots; the wood is a light yellow-white, with a yellowish-brown cambial ring. B. Root head (dang gui tou) The root head consists of the uppermost cm of the root; cm in diameter, apex obtuse and rounded, annulate; may show purple or yellowish-green remnants of stems and leaf sheaths. C. Root body (dang gui shen) 3-5 cm long, 1-4 cm in diameter; typically sulfured, with the outer bark scraped off, revealing a white to light brown relatively smooth surface; unpeeled roots have a bumpy or gnarled surface. D. Root tails (dang gui wei) The main flexible branching roots are ~ cm long and 6-15 mm in diameter where they emerge from the root body; somewhat twisted and tapering, with few rootlet scars; finer branch roots from 1 mm in diameter at the apex. E. Sliced roots Longitudinal slices tapering in outline, ~ cm across at apex, cm long, ~ mm thick; upper portion straight to slightly tapering in outline, dividing below into several narrow, slightly tapering branches ~ cm wide; internal surface a light yellow to yellowbrown, the thick bark forming a dark brown to orangebrown outline around the edge. F. Sliced and pressed roots (palm slices) Molar-shaped, cm across at apex, up to 20 cm long, < 0.1 mm thick; branch roots typically 4-6 (the others having been removed); generally sulfured and of a light to medium yellow in color with brown edges when the bark is present; surface smooth, texture coriaceous and pliable if of good quality. Fracture: Whole roots: Short, uneven, to somewhat flexible depending on moisture and oil content. Palm slices: Flexible to short, depending on moisture and oil content. Aroma: Strongly aromatic (due to alkylphthalides), reminiscent of celery; slightly smoky (due to processing). Taste: Sweet, pungent, slightly bitter. Powder: Yellowish-brown. QUANTITATIVE STANDARDS Foreign Organic Matter: Not to exceed 3% leaf sheath and 1% other foreign matter. Total Ash: Not to exceed 7%. Acid-insoluble Ash: Not to exceed 2%. Ethanol-soluble Extractives: Not less than 45% using 70% ethanol as a solvent.

2 QUALITATIVE DIFFERENTIATION There are a variety of grades of dang gui sold commercially. Most of these are priced according to root size, with larger roots commanding higher prices. Premier quality dang gui is reportedly very aromatic and oily and soft and pliable, with a light golden brown to brown exterior and a yellowish-white interior. Roots that are woody, withered, lack oil, or have a greenishbrown interior, should not be used medicinally. POTENTIAL ADULTERANTS Lovage (Levisticum officinale Koch), also known as European dang gui (Ou dang gui), has been sold as a substitute for true dang gui (Angelica sinensis). Dang gui and L. officinale whole roots can be distinguished macroscopically (Figure 10-12). In contrast to dang gui, L. officinale root has a grayish brown exterior surface which is heavily furrowed longitudinally with no horizontal lenticels. The numerous flexible branch roots occurring in dang gui are missing in L. officinale. The xylem tissue in L. officinale is deep yellow, while in dang gui it is light yellow. For a discussion of the microscopic and chemical differentiation of dang gui and L. officinale, see the AHP Dang gui Root monograph (2003). Other botanicals that have been traded as dang gui include Angelica acutiloba (dong dang gui; grown in northeast China and Japan), Angelica megaphylla (da ye dang gui; used in Sichuan), Angelica valida (Jin Shan dang gui; used in Sichuan), Angelica tsinglingensis (Qinling dang gui; grown in the Qinling mountains in Shaanxi), and Ligusticum glaucescens (ye dang gui; grown in Yunnan). In Korea, Angelica gigas (Chaoxian dang gui or Cham-dang-gui; grown in northeast China) and Angelica uchiyamana (grown in Korea, possibly in China as well) may be found in trade. Figure 1 Pressed botanical specimen of dang gui. Institute of Medicinal Plant Development - Beijing (IMPLAD) 1. Root head (dang gui tou). 2. Root body (dang gui shen). 3. Root tails (dang gui wei) 2 cm Figure 2 Traditional separation of whole dang gui root (Angelica sinensis) into sections with differing therapeutic properties. Source: Zhao 1999.

3 Figure 3 Dried whole roots with finer branch roots intact. Figure 4 Dried whole roots with finer branch roots removed. Figure 5 Whole dang gui root (close-up). Figure 6 Whole roots sliced and unsulfured (left) and sliced, pressed, and sulfured (palm slice; right). The pressed slice is a composite of 3 different roots.

4 Figure 7 Palm sliced dang gui composite of 3 different roots (see Figure 8). Figure 8 A pressed slice (same as shown in Figure 7) soaked in water showing separation of the 3 roots. Figure 9 Dried root bodies, sliced and unsulfered (left) and peeled and sulfured (right). Figure 10 Comparison of whole dang gui (left) and Levisticum officinale (right) (European sample).

5 Figure 11 Comparative cross sections of dang gui (right) and Levisticum officinale (left) (European sample). Figure 12 Comparative longitudinal sections of dang gui (right) and Levisticum officinale (left) (European sample).