Rhizoma et Radix Baphicacanthis Cusiae
Baphicacanthus Root is the dried rhizome and root of Baphicacanthus cusia (Nees) Bremek. (Fam. Acanthaceae). The drug is collected in summer and autumn, deprived from the aerial part, washed clean, and dried in the sun.
Description: Rhizome subrounded, mostly tortuous, branched, 10-30 cm long, 0.1-1.0 cm in diameter. Externally greyish-brown, fine wrinkled longitudinally; nodes swollen, bearing rootlets and remained with stem scars; outer bark easily exfoliated, bluish-grey. Texture hard and fragile, easily broken, fracture uneven, bark bluish-grey, wood greyish-blue to pale yellowish-brown, pith in the centre. Root varying in thickness, curved and branched, rootlets slender and flexible. Odour, slightly; taste, week.
Identification: (1) Transverse section: Cork consisting of several rows of cells, containing brown contents. Cortex broad, having serveral rows of collechyma outside; endodermis distinct; stone cells visible. Phloem relatively narrow, phloem fibres more frequent. Xylem broad, all the cells in it lignified; vessels single or 2-4-grouped, arranged radially; xylem rays broad. In pith cells subrounded or polygonal, stone cells found occasionally. Some parenchymatous cells containing elliptical cystoliths.
(2) To 2 g of the powder add 20 ml of ethanol, heat under reflux for 1 hour, filter, apply several drops of filtrate to a filter paper, dry in air, examine under ultraviolet light (365 nm), a purplish-red fluorescence appears. Evaporate the remaining filtrate to dryness, dissolve the residue in 1 ml of glacial acetic acid, add 1 ml of acetic anhydride and 1 drop of sulfuric acid, the colour of the solution turns gradually from yellow to red, purple, blue then to dark green.
(3) To 2 g of the powder add 20 ml of chloroform, heat under reflux for 1 hour, filter, concentrate the filtrate to 2 ml as the test solution. Dissolve indigotine CRS and indirubin CRS in chloroform to produce a mixture containing 1 mg of indigotine and 0.5 mg of indirubin per ml as the reference solution. Carry out the method for thin layer chromatography (Appendix VI B), using silica gel G as the coating substance and benzene-chloroform-acetone (5:4:1) as the mobile phase. Apply separately 10 ml of each of the above two solutions to the plate. After developing and removal of the plate, dry it in air, examine immediately under daylight. A blue spot and a purplish-red spot in the chromatogram obtained with the test solution correspond in position and colour to the spots in the chromatogram obtained with the reference solution respectively.
Water: Not more than 12% (Appendix IX H, method 1).
Total ash: Not more than 10% (Appendix IX K).
Processing: Eliminate foreign matter, wash clean, soften thoroughly, cut into thick slices, and dry.
Action: To remove heat and counteract toxicity, reduce heat from blood.
Indications: Eruptive epidemic diseases, erysipelas, influenza, epidemic meningitis.
Usage and dosage: 9-15 g.
Storage: Preserve in a dry place, protected from mould and moth.