Chuan Xin Lian

ANDROGRAPHIS HERBA (穿心莲, Chuanxinlian) Common Andrographis Herb The dried aerial parts of Andrographis paniculata (Burm. f.) Nees (Fam. Acanthaceae). The drug is collected in early autumn when the stems and leaves are luxuriant, and dried in the sun. Description Stems quadrangular, frequently branched, 50–70 cm long; nodes slightly swollen. Texture brittle, easily broken. Leaves simple, opposite, shortly petiolate or nearly sessile. Leaf blades crumpled and easily broken; when intact, lanceolate or ovate-lanceolate, 3–12 cm long and 2–5 cm wide, apex acuminate, base cuneate-decurrent, margin entire or slightly undulate. Upper surface green; lower surface greyish-green. Both surfaces glabrous. Odour slight. Taste extremely bitter. Identification (1) Transverse section of leaf Upper epidermal cells subsquare or rectangular. Lower epidermal cells relatively small. Both epidermises contain crystal cells with rounded, elongated, or clavate cystoliths. Glandular scales and occasional non-glandular hairs present. Palisade tissue consisting of 1–2 layers of cells, extending across the upper side of the midrib. Spongy tissue loosely arranged. Midrib vascular bundles collateral and grooved. Crystal cells occur above the xylem. Surface view of leaf Large crystal cells present in both upper and lower epidermises. Each contains a large conchoidal cystolith, up to 36 μm in diameter and 180 μm long, with a hilum-like scar at the broader end and concentric wavy striations. Stomata more numerous on the lower epidermis. Stomata diacytic; subsidiary cells vary markedly in size; occasional anomocytic stomata also present. Glandular scales with oblate heads composed of 4, 6, or 8 cells, up to 40 μm in diameter. Stalks very short. Non-glandular hairs composed of 1–4 cells, up to 160 μm long and 40 μm in diameter, with cuticular striations on the surface. (2) Thin-layer chromatography Prepare the reference drug solution by adding 25 mL of 40% methanol to 0.5 g of Andrographis Herba Reference Drug, ultrasonicate for 30 minutes, filter, and use the filtrate. Carry out Thin-Layer Chromatography (0502) using silica gel G as the coating substance and a mixture of chloroform, toluene, and methanol (8:1:1) as the mobile phase. Apply separately 10 μL each of: the test solution obtained under Assay, the reference solution obtained under Assay, and the reference drug solution. After development, remove the plate and dry in air. Spray with 10% sulfuric acid in ethanol. Heat at 105°C until the spots become clearly visible. Examine under ultraviolet light (365 nm). The fluorescent spots in the chromatogram obtained with the test solution correspond in position and colour to those obtained with the reference drug solution. The principal fluorescent spot also corresponds in position and colour to that obtained with the reference solution. Leaves Not less than 30.0%. Extractives Carry out the method for determination of ethanol-soluble extractives (2201, Hot Extraction Method), using ethanol as the solvent. Not less than 8.0%. 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 acetonitrile as Mobile Phase A and water as Mobile Phase B. Elute according to the following gradient program: Time (min) Mobile Phase A (%) Mobile Phase B (%) 0–15 20 → 25 80 → 75 15–30 25 → 28 75 → 72 30–60 28 → 40 72 → 60 60–65 40 → 85 60 → 15 Detection wavelength: 205 nm. The number of theoretical plates shall be not less than 8000, calculated with reference to the peak of andrographolide. Reference solution Accurately weigh Andrographolide CRS. Dissolve in methanol to prepare a solution containing 0.3 mg/mL. Test solution Accurately weigh about 0.5 g of the powder (through No. 4 sieve) into a stoppered conical flask. Accurately add 25 mL of 40% methanol. Stopper tightly and weigh. Ultrasonicate (power 250 W, frequency 40 kHz) for 30 minutes. Cool. Weigh again. Replace any loss of solvent with 40% methanol. Mix well. Filter. Use the subsequent filtrate as the test solution. Procedure Inject accurately 5 μL each of the reference solution and the test solution into the chromatograph. Using the andrographolide peak as the reference, determine the relative retention times of neoandrographolide, 14-deoxyandrographolide, and dehydroandrographolide. The relative retention times and correction factors are as follows: Compound Relative Retention Time Correction Factor Andrographolide 1.00 1.00 Neoandrographolide 1.95 1.12 14-Deoxyandrographolide 2.18 0.79 Dehydroandrographolide 2.25 0.63 The relative retention times of the test peaks shall remain within ±5% of the above values. If the deviation exceeds ±5%, confirmation shall be made using the corresponding reference standard. Using the peak area of andrographolide as the external standard, calculate the contents of neoandrographolide, 14-deoxyandrographolide, and dehydroandrographolide with their respective correction factors. It contains not less than 1.5% of the total amount of: Andrographolide (C₂₀H₃₀O₅) Neoandrographolide (C₂₆H₄₀O₈) 14-Deoxyandrographolide (C₂₀H₃₀O₄) Dehydroandrographolide (C₂₀H₂₈O₄) calculated with reference to the dried drug. Prepared Slices Processing Remove foreign matter. Wash clean. Cut into sections. Dry. Description Irregular sections. Stems quadrangular, with slightly swollen nodes. Fracture uneven; pith whitish. Leaves mostly crumpled or broken; when intact, lanceolate or ovate-lanceolate, with an acuminate apex and cuneate-decurrent base; margins entire or slightly undulate. Upper surface green; lower surface greyish-green. Both surfaces glabrous. Odour slight. Taste extremely bitter. Identification As required for the crude drug, except for the transverse section of the leaf. Leaves Not less than 25.0%. Assay Following the method for the crude drug, it contains not less than 1.2% of the total amount of: Andrographolide (C₂₀H₃₀O₅) Neoandrographolide (C₂₆H₄₀O₈) 14-Deoxyandrographolide (C₂₀H₃₀O₄) Dehydroandrographolide (C₂₀H₂₈O₄) calculated with reference to the dried drug. Property and Flavor Cold; bitter. Meridian Tropism Heart, Lung, Large Intestine, and Bladder meridians. Actions To clear heat, remove toxin, cool the blood, and reduce swelling. Indications Common cold with fever, swollen and painful throat, sores of the mouth and tongue, pertussis, cough due to lung consumption, diarrhea, dysentery, heat strangury with difficult and painful urination, carbuncles, sores, ulcers, and bites from insects, worms, or snakes. Administration and Dosage 6–9 g. For external use, apply an appropriate amount. Storage Preserve in a dry place.