Cassia Twig is the dried young branch of Cinnamomum cassia Presl (Fam. Lauraceae). The drug is collected in spring and summer, removed from leaf, dried in the sun, or dried in the sun after sliced.
Description: Long cylindrical, much-branched, 30-75 cm long, thick end 0.3-1 cm in diameter. Externally brown to reddish-brown, with longitudinal ridges, fine wrinkles, dotted leaf-scars, branch-scars and bud-scars, lenticels dotted. Texture hard and fragile, easily broken. Slices 2-4 mm thick, cut surface showing reddish-brown in bark, yellowish-white to pale yellowish-brown in wood, pith subsquare. Odour, characteristically aromatic; taste, sweet and slightly pungent, relatively strong for bark.
Identification: (1) Transverse section: Epidermis consisting of 1 layer of cells, non-glandular hairs unicellular, visible in young branches. Cork consisting of 3-5 layers of cells, the inmost cells with thickened outer walls. Oil cells and stone cells scattered in cortex. Groups of stone cells in pericycle interruptedly arranged in a ring, accompanied by fibre bundles. Secretory cells and fibres scattered in phloem. Cambium distinct. Xylem rays 1-2 cells wide, containing brown contents; vessels scattered singly or 2 to several aggregated; xylary fibres with relatively thin walls, and differentiated uneasily from xylary parenchymatous cells. In pith, the walls of cells slightly thickened and lignified. Cells of rays containing fine needle crystals of calcium oxalate.
(2) To 0.5 g of the powder add 10 ml of ethanol, stoppered tightly, macerate for 20 minutes with frequent shaking, filter, use the filtrate as the test solution. Dissolve cinnamic aldehyde CRS in ethanol to produce a solution containing 1 ml 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 a mixture of petroleum ether (60-90oC)-ethyl acetate (85:15) as the mobile phase. Apply separately to the plate 10-15 ml of the test solution and 2 ml of the reference solution. After developing and removal of the plate, dry it in air, and spray with a 0.1% solution of 2, 4-dinitrophenyl-hydrazine in ethanol. The orange-red spot in the chromatogram obtained with the test solution corresponds in position and colour to the spot in the chromatogram obtained with the reference solution.
Processing: Eliminate foreign matter, soak briefly, wash clean, soften thoroughly, cut into thin slices, and dry in air.
Slices subrounded, elliptic, or sections irregular, possessing dotted lenticels and longitudinal ridges, bark reddish brown, wood yellowish-white or pale yellowish-brown, pith subrounded or slightly square.
Action: To induce perspiration, to warm the channels and stimulate menstrual discharge, to reinforce yang, to relieve palpitation, and to promote the descending of qi.
Indications: Common cold; epigastric pain with cold feeling; amenorrhea due to cold in blood; arthralgia; edema; cardiac palpitation; gastro-intestinal neurosis with a feeling of masses of gas rushing up through the chest to the throat from the lower abdomen.
Usage and dosage: 3-9 g.
Storage: Preserve in a cool and dry place.