Canton Love-pea Vine is the dried herb of Abrus cantoniensis Hance(Fam.Leguminosae). The drug is collected all the year round, removed from soil, and dried.
Description: Roots mostly conical, the upper part thick and the lower part thin, branched, varying in length, 0.5-1.5 cm in diameter. Externally greyish-brown, rough, with fine, longitudinal striations, rootlets extremely slender, some fallen off or with remainings; texture hard. Stems caespitose, 50-100 cm long, about 0.2 cm in diameter; greyish-brown to purplish-brown, branchlets slender, sparsely pubescent. Leaves pinnately compound, alternate, leaflets in 8-11 pairs, mostly fallen off, oblong, 0.8-1.2 cm long, apex truncate, mucronulate, the lower surface with pronated hairs. Odour, slightly aromatic; taste, slightly bitter.
Identification:(1) Powder: Greyish-green. Non-glandular hairs unicellular, acute or acuminate at the apex, 60-970 mm long, 12-22 mm in diameter, walls 3-6 mm thick, with distinct striations and warty prominences. Stomata paracytic. Fibre bundles surrounded by cells containing prisms of calcium oxalate, forming crystal fibres, walls of crystal cells irregularly thickened. Stone cells subrounded, subsquare or oblong, 16-40 mm in diameter, some with slightly thickened walls. Cork cells yellowish-brown. Prisms of calcium oxalate 5-11 mm in diameter.
(2) To 10 g of the coarse powder add 100 ml of 70% ethanol, heat under reflux on a water bath for 30 minutes and filter. Divide the filtrate into two portions, and evaporate to dryness. Dissolve one portion of the residue in 10 ml of water, filter, to 2 ml of the filtrate add 2 ml of 0.1% solution of ferric chloride in glacial acetic acid, shake well, add 2 ml of sufuric acid slowly along the wall, a reddish-brown colour is produced immediately at the junction of the two layers.
(3) To another portion of the residue obtained under Identification test(2), add 10 ml of 1% hydrochloric acid solution to dissolve, filter. To the residue add 10 ml of 10% sodium hydroxide solution, heat under reflux on a water bath for 30 minutes and allow to cool, transfer the mixture to a separator, extract with 20 ml of ether, separate the ether layer and evaporate to dryness, dissolve the residue in 1 ml of glacial acetic acid, add 1 ml of a mixture containing 19 portions of acetic anhydride and 1 portion of sulfuric acid, a yellow colour is produced and changes gradually to a dull green colour.
Processing: Eliminate foreign matter and legumes, and cut into sections.
Action: To remove toxic heat, and to relieve the depressed liver and alleviate pain.
Indications: Jaundice with hypochondriac distress and epigastric distension and pain; acute and chronic hepatitis; mastitis.
Usage and dosage: 15-30 g.
Storage: Preserve in a dry place.