สารบัญ

       Cannabis Sativa Root is the dried root of Cannabis sativa L. [C. indica Lam., C. ruderalis Janisch., C. ruderalis (Janisch.) S. Z. Liou, C. sativa L. subsp. indica (Lam.) E. Small & Cronquist, C. sativa L. var. indica (Lam.) Wehmer] (Family Cannabaceae), Herbarium Specimen Number: DMSC 5268, Crude Drug Number: DMSc 1213.

Constituents Cannabis Sativa Root contains triterpenoids (e.g., epifriedelinol and friedelin). It also contains sterols, alkaloids, polyphenols, etc.

Description of the plant (Fig. 1) Herbaceous plant, dioecious, occasionally monoecious, 0.2 to 6 m tall; stem and branches angular, erect, covered with rather short stiff hairs. Leaves palmately compound, opposite near base, spirally arranged upwards; petiole up to 10 cm long, pubescent; stipule erect, linear or narrowly subulate, 4 to 6 mm long, persistent; leaflets (3–)5 to 11, narrowly lanceolate, linear to linear-lanceolate, 2 to 15 cm long, 0.2 to 2 cm wide, apex acuminate-caudate, base narrowly cuneate, margin coarsely serrate, upper surface dark green, scabrous, lower surface whitish green with scattered brownish resinous dots, densely pubescent with appressed hairs, nerves 8 to 20 pairs; sessile. Flowering top numerous inflorescences, terminal or axillary; male inflorescence diffused and paniculate, bracts small; female inflorescence crowded among foliaceous bracts, 1 to 5 cm long. Flower small; male flower yellowish green, tepals 5, free, elliptic or oblong, 3 to 5 mm long, 1.5 to 2 mm wide, apex acute, margin entire, finely pubescent; stamens 5, opposite tepals, filament slender, 0.5 to 1 mm long, anther basifixed, oblong, 2-celled, dehiscing by apical pore; female flower greenish, subsessile, enveloped by perigonal bract, membranous spathe-like, dark green, with glandular hairs; tepals fused into thin-textured tube adnate to ovary, in some cultivars, merely a ring at base of ovary; ovary superior, subglobose, 1 to 2 mm in diameter, 1-loculed, style short divided into 2 stigmatic slender arms, brown, pubescent, caducous. Fruit an achene, ovoid or ellipsoid, 2 to 5 mm long, 3 to 4 mm wide, somewhat compressed, minutely pilose to glabrous, shiny, yellowish brown to white or greenish, mottled with purple pericarp crustaceous, finely reticulate. Seed 1.

Description Odourless; taste, bland.

       Macroscopical (Fig. 1) Tap root cylindrical, up to 5 cm in diameter, whitish to pale brown, various lengths. Secondary roots numerous, varied in length, slender, whitish to pale brown, up to 1.5 mm in diameter.

       Microscopical (Figs. 2a, 2b) Transverse section of the root shows cork, cortex, vascular tissue, and pith. Cork: several layers of thin-walled rectangular cells. Cortex: polygonal and rectangular parenchyma cells. Vascular tissue: phloem, small thin-walled round parenchyma, phloem ray, and phloem fibres; xylem, vessels, xylem ray, some containing starch grains, and xylem fibres. Pith: thick-walled round parenchyma, some containing rosette aggregate crystals.

     Cannabis Sativa Root in powder possesses the diagnostic microscopical characters of the unground drug. The combination of thin-walled cork, uniseriate and biseriate medullary rays in tangential view, and various sizes of starch grains should be characteristic.

Additional information

       1. It is commonly used with other herbal drugs in Thai traditional herbal preparations.

       2. It is to be noted that traces of cannabinoids may be found in cannabis roots. Packaging and storage Cannabis Sativa Root shall be kept in well-closed containers, protected from light, and stored in a dry place.

Identification

        A. Macerate 500 mg of the sample, in powder, with 5 mL of chloroform for 15 minutes and filter. Evaporate 1 mL of the filtrate to dryness. Dissolve the residue in 1 mL of acetic anhydride, shake well, and slowly add 1 mL of sulfuric acid to form a layer: a brown colour develops at the zone of contact and the upper layer is bluish green.

       B. Carry out the test as described in the “Thin-Layer Chromatography” (Appendix 3.1), using a high-performance plate with silica gel 60F254 as the coating substance and a mixture of 90 volumes of n-hexane and 10 volumes of ethyl acetate as the mobile phase and allowing the solvent front to ascend 8 cm above the line of application. Apply separately to the plate, as bands of 8 mm, 10 µL of solution (A) and 5 µL of solution (B). Prepare solution (A) by macerating 1 g of the sample, in powder, with 5 mL of chloroform, shaking for 10 minutes and filtering. For solution (B), dissolve 1 mg of friedelin in 1 mL of chloroform. After removal of the plate, allow it to dry in air. Spray the plate with anisaldehyde TS and heat at 105° for 5 minutes. The chromatogram obtained from solution (A) shows a yellow band (hR_f value 46 to 49), corresponding to the friedelin band obtained from solution (B). Two purple and two violet bands are also observed (Fig. 3).

Loss on drying Not more than 8.0 per cent w/w after drying at 105° to constant weight (Appendix 4.15).

Foreign matter Not more than 2.0 per cent w/w (Appendix 7.2).

Acid-insoluble ash Not more than 1.5 per cent w/w (Appendix 7.6).

Total ash Not more than 8.0 per cent w/w (Appendix 7.7).

Ethanol-soluble extractive Not less than 2.0 per cent w/w (Appendix 7.12).

Water-soluble extractive Not less than 4.0 per cent w/w (Appendix 7.12).