Atractylodes Rhizome is the dried rhizome of Atractylodes lancea (Thunb.) DC. or Atractylodes chinensis (DC.) Koidz. (Fam. Compositae). The drug is collected in spring and autumn, removed from soil, dried, and dashed to discard the fibrous roots.
Description: Rhizome of Atractylodes lancea Irregularly moniliform or nodular-cylindrical, somewhat curved, occasionally branched, 3-10 cm long, 1-2 cm diameter. Externally greyish-brown, wrinkled, transversly twisted-lined, with remains of rootles, and stem scars or remains of stems attached at apex. Texture compact, fracture yellowish-white or greyish-white, scattered with many orange-yellow or brownish-red oil cavities and crystallized out as white fine needle crystals after exposing for a long time. Odour, characteristic; taste, sweetish, pungent and bitter.
Rhizome of Atractylodes chinensis: Knotty-lumpy or nodular-cylindrical, 4-9 cm long, 1-4 cm in diameter. Externally blackish-brown, yellowish-brown when peeled. Texture lax, fracture scattered with yellow oil cavities. Odour weakly aromatic; taste, pungent and bitter.
Identification: (1) Powder: Brown. Needle crystals minute, 5-30 mm long, irreguarly filled in parenchymatous cells. Fibres mostly in bundles, long fusiform, up to 40 mm in diameter, with rather thickened lignified walls. Stone cells fairly abundant, sometimes linking up with cork cell, polygonal, subrounded or subrectangular, 20-80 mm in diameter, with heavily thickened walls. Inulin frequently visible, with radial striations on surface.
(2) To 0.5 g of the powder add 2 ml of n-hexane, ultrasonicate for 15 minutes, filter, and use the filtrate as the test solution. Prepare a solution of 0.5 g of Rhizoma Atractylodis reference drug in the same manner as the reference drug solution. Carry out the method for thin layer chromatography (Appendix VI B), using silica gel G as the coating substance and petroleum ether (60-90oC)-ethyl acetate (20:1) as the mobile phase. Apply separately to the plate 2-6 ml each of the above two freshly prepared solutions. After developing and removal of the plate, dry it in air, and spray with 5% solution of p-dimethylaminobenzaldehyde in ethanol containing 10% sulfuric acid, heat to the spots distinct. The spots in the chromatogram obtained with the test solution correspond in position and colour to the spots in the chromatogram obtained with the reference drug solution, and a same muddy green principal spot (atractydin) is shown in both chromatograms.
Total ash: Not more than 7.0% (Appendix IX K).
Processing: Rhizoma Atractylodis Eliminate foreign matter, wash clean, soften thoroughly, cut into thick slices, and dry.
Rhizoma Atractylodis (stir-baked with bran): Stir-bake the slices of Rhizoma Atractylodis as described under stir-baking with bran (Appendix II D) until its outer surface becomes deep yellow.
Subrounded or slat-shaped thick slice, scraps not more than 3% (Appendix IX B).
Action: To remove damp and invigorate the function of the spleen, to disple wind-cold, and to improve eyesight.
Indications: Epigastric distension and diasrrhea; edema, particularly edema of the legs with lameness; rheumatic arthralgia; common cold; night blindess.
Usage and dosage: 3-9 g.
Storage: Preserve in a cool and dry place.