Chuan Xiong

CHUANXIONG RHIZOMA (川芎, Chuanxiong) Szechwan Lovage Rhizome The dried rhizome of Ligusticum chuanxiong Hort. (Fam. Umbelliferae). The drug is collected in summer when the stem nodes become obviously swollen and purplish, removed from the soil, dried in the sun and then gently baked to dryness, and the fibrous roots are removed. Description Irregularly nodular and fist-shaped, 2–7 cm in diameter. Externally greyish-brown or brown, rough and shrivelled, with numerous parallel, raised annulations. The apex bears depressed, subrounded stem scars. The lower part and the nodes bear numerous tuberculate rootlet scars. Texture compact and difficult to break. Fracture yellowish-white or greyish-yellow, scattered with yellowish-brown oil cavities. Cambium forming an undulate ring. Odour strongly aromatic. Taste bitter, pungent, slightly numbing, followed by a slightly sweet aftertaste. Identification (1) Transverse section Cork consisting of more than 10 layers of cells. Cortex narrow, scattered with root-trace vascular bundles. Cambium distinct. Phloem broad. Cambium undulate or irregularly polygonal. Xylem vessels polygonal or subrounded, mostly arranged in single radial rows or V-shaped groups. Wood fibre bundles occasionally present. Pith relatively large. Numerous oil cavities scattered throughout the parenchyma, subrounded, elliptic or irregular, pale yellowish-brown, small near the cambium and gradually becoming larger toward the periphery. Parenchymatous cells containing abundant starch granules. Some cells containing subrounded crystals or clusters of calcium oxalate. Powder Pale yellowish-brown or greyish-brown. Starch granules abundant. Simple granules ellipsoidal, oblong, subrounded, ovoid or reniform, 5–16 μm in diameter and up to 21 μm long. Hilum punctate, slit-shaped or V-shaped. Compound granules occasionally present, consisting of 2–4 components. Calcium oxalate crystals occurring in parenchymatous cells, subrounded or clustered, 10–25 μm in diameter. Cork cells dark yellowish-brown, polygonal in surface view, with slightly sinuous walls. Oil cavities mostly broken; fragments occasionally visible. Secretory cells thin-walled and containing numerous oil droplets. Vessels mainly spiral; reticulate and scalariform vessels also present, 14–50 μm in diameter. (2) Macerate 1 g of the powder with 5 mL of petroleum ether (60–90°C) for 10 hours, shaking occasionally. Allow to stand. Evaporate 1 mL of the supernatant to dryness. Dissolve the residue in 1 mL of methanol. Add 2–3 drops of 2% 3,5-dinitrobenzoic acid in methanol, followed by 2 drops of saturated potassium hydroxide solution in methanol. A purplish-red colour is produced. (3) To 1 g of the powder add 20 mL of ether. Heat under reflux for 1 hour. Filter. Evaporate the filtrate to dryness. Dissolve the residue in 2 mL of ethyl acetate as the test solution. Prepare a solution of 1 g of Chuanxiong Rhizoma Reference Drug in the same manner as the reference drug solution. Dissolve Levistolide A CRS in ethyl acetate (in an amber volumetric flask) to prepare a solution containing 0.1 mg/mL as the reference solution. Carry out the method for Thin-Layer Chromatography (0502) using silica gel GF254 as the coating substance and a mixture of n-hexane and ethyl acetate (3:1) as the mobile phase. Apply separately 10 μL of each of the three solutions to the plate. After development, remove the plate and dry in air. Examine under ultraviolet light (254 nm). The spots obtained with the test solution correspond in position and colour to those obtained with the reference drug solution and the reference solution. Water Not more than 12.0% (0832, Method 4). Total Ash Not more than 6.0% (2302). Acid-insoluble Ash Not more than 2.0% (2302). Extractives Carry out the method for determination of ethanol-soluble extractives (2201, Hot Extraction Method), using ethanol as the solvent. Not less than 12.0%. Assay Carry out the method for High-Performance Liquid Chromatography (0512). Chromatographic system and system suitability Use octadecylsilane-bonded silica gel as the stationary phase. Use a mixture of methanol and 1% acetic acid (30:70) as the mobile phase. Detection wavelength: 321 nm. The number of theoretical plates shall be not less than 4000, calculated with reference to the peak of ferulic acid. Reference solution Accurately weigh Ferulic Acid CRS. Dissolve in 70% methanol (in an amber volumetric flask) to prepare a solution containing 20 μg/mL. Test solution Accurately weigh 0.5 g of the powder (through No. 4 sieve) into a stoppered conical flask. Accurately add 50 mL of 70% methanol. Stopper tightly and weigh. Heat under reflux for 30 minutes. Cool. Weigh again. Replace any loss of solvent with 70% methanol. Mix well. Allow to stand. Filter. Use the subsequent filtrate as the test solution. Procedure Inject accurately 10 μL of the reference solution and the test solution, respectively. Determine and calculate the content. The drug contains not less than 0.10% of ferulic acid (C₁₀H₁₀O₄), calculated with reference to the dried drug. Prepared Slices Processing Remove foreign matter. Grade according to size. Soak briefly. Wash clean. Soften thoroughly. Cut into thick slices. Dry. Description Irregular thick slices. Outer bark greyish-brown or brown with wrinkles. Cut surface yellowish-white or greyish-yellow, showing a distinct undulate cambium ring or polygonal striations, scattered with yellowish-brown oil cavities. Texture compact. Odour strongly aromatic. Taste bitter, pungent, slightly numbing, followed by a slightly sweet aftertaste. Identification As required for the crude drug. Water, Total Ash, Acid-insoluble Ash, and Extractives As required for the crude drug. Assay As required for the crude drug. Property and Flavor Warm; pungent. Meridian Tropism Liver, Gallbladder, and Pericardium meridians. Actions To invigorate the blood, promote the movement of qi, dispel wind, and relieve pain. Indications Chest bi syndrome with cardiac pain, stabbing pain in the chest and hypochondrium, traumatic swelling and pain, menstrual irregularities, amenorrhea, dysmenorrhea, abdominal pain with masses, headache, and painful bi syndrome due to wind-dampness. Administration and Dosage 3–10 g. Storage Preserve in a cool and dry place, protected from insects.