สารบัญ

ระย่อม (RAYOM)
กะย่อม (KAYOM), ย่อมตีนหมา (YOM TIN MA)
Rauvolfiae Serpentinae Radix
Indian Snakeroot
Synonym Serpentine Root
Category Antihypertensive, antipyretic.
         Indian Snakeroot is the dried root of Rauvolfia serpentina (L.) Benth. ex Kurz
[Ophioxylon album Gaertn., O. obversum Miq., O. salutiferum Salisb., O. serpentinum L.,
O. trifoliatum Gaertn., Rauvolfia obversa Baill., R. serpentina (L.) Benth. ex Kurz var. obversa
(Miq.) Bakh. f., and R. trifoliata Baill.] (Family Apocynaceae), Herbarium Specimen
Number: DMSC 5365, Crude Drug Number: DMSc 1256.
Constituents Indian snakeroot contains indole alkaloids (e.g., ajmalicine, ajmaline, reserpine,
serpentine), and tannins, etc.
Description of the plant (Fig. 1) Shrub up to 1 m tall with latex; stem erect, slender,
glabrous; branchlet often angled, glabrous; root elongated. Leaves simple, in whorl of 3 to 5,
rarely opposite, narrowly elliptic to obovate, 4 to 25 cm long, 1.5 to 10 cm wide, apex
acuminate or rarely obtuse, base cuneate, margin entire, papery, glabrous, lateral veins in
7 to 16 pairs, arcuate ascending; petiole 1 to 3.5 cm long. Inflorescence cymose, usually
solitary, terminal or axillary, 4.5 to 11.5 cm long; peduncle 3 to 7.8 cm long, glabrous. Flower:
pedicel 2.2 to 6.5 mm long; calyx reddish, glabrous, base connate, lobes 5, ovate or lanceolate,
1.8 to 4.2 mm long, 0.5 to 1.5 mm wide, apex acute to acuminate; corolla white, reddish,
pinkish or purplish, tube 1.5 to 2 mm long, lobes 5, overlapping to the left in bud, mature
corolla salverform, lobe obliquely suborbicular, 2 to 5.6 mm long, glabrous outside, pubescent
in mouth and inside to just beneath stamens or in mouth and around stamens with a glabrous
band between; stamens 5, inserted at 0.8 to 1.1 cm from base of corolla tube, filament 0.5 to
1 mm long, anther oblong; disc annular, 0.3 to 0.8 mm long; ovary superior, 0.8 to 1.6 mm
long, carpels 2, connate at base, style and stigma 6.2 to 9.6 mm long. Fruit a drupe, paired,
connate at base, ovoid, 5.4 to 9 mm long, 4.2 to 4.7 mm wide, green when young, becoming
blackish purple when ripe. Seed 1, ovoid, flattened, about 4 mm long, about 2.8 mm wide.
Description Odourless; taste, very bitter.
     Macroscopical (Fig. 1) Dried roots, various lengths and diameters, stout, thick, tortuous,
and frequently curved and twisted. Externally greyish yellow to brown, internally whitish
grey. Surface slightly wrinkled and rough with coarse longitudinal markings.
     Microscopical (Figs. 2a, 2b) Transverse section of the root shows periderm, cortex, and
vascular tissue. Periderm: lenticels, numerous layers of rectangular cork cells, some
containing brown substances, and/or starch grains. Cortex: parenchyma, containing starch
grains and/or some prismatic crystals. Vascular tissue: phloem and xylem; phloem
comprising parenchyma, some containing starch grains and/or some prismatic crystals, and
phloem ray; xylem consisting of tracheid-vessels, few vessels, xylem ray (some containing
starch grains), pitted parenchyma, and xylem fibres.
     Indian Snakeroot in powder possesses the diagnostic microscopical of the unground
drug. Tracheid-vessels, rarely found in other crude drug of Dicotyledonae origin,
are characteristic. Cork in surface view and starch grains can be seen in abundance.

Contra-indication It is contra-indicated in patients with a history of mental depression.
Packaging and storage Indian Snakeroot shall be kept in well-closed containers, protected
from light, and stored in a dry place.
Identification
      A. Sonicate 500 mg of the sample, in powder, with 10 mL of ethanol for 30 minutes and
filter (solution 1). To 2 mL of solution 1, add a few drops of modified Dragendorff TS: an orange
precipitate is produced.
      B. To 2 mL of solution 1, add a few drops of a 1 per cent w/v solution of iron(III) chloride
and shake well: a blue-green colour develops.
      C. Carry out the test as described in the “Thin-Layer Chromatography” (Appendix 3.1),
using silica gel GF254 as the coating substance and a mixture of 70 volumes of toluene,
20 volumes of diethylamine, and 10 volumes of formic acid as the mobile phase and allowing
the solvent front to ascend 8 cm above the line of application. Apply to the plate as bands of
6 mm, 1 μL each of solutions (A), (B), and (C). Prepare solution (A) by sonicating 3 g of the
sample, in No. 250 powder, with 60 mL of ethanol for 30 minutes and filtering. Evaporate the
filtrate to dryness under reduced pressure at 50°. Dissolve the residue in 2 mL of ethanol.
For solution (B), dissolve 2 mg of reserpine in 1 mL of methanol. For solution (C), dissolve 2 mg
of ajmalicine in 1 mL of methanol. After removal of the plate, allow it to dry in air and examine
under ultraviolet light (254 nm), marking the quenching bands. The chromatogram obtained
from solution (A) shows quenching bands (hR_f values 60 to 65 and 75 to 80) corresponding to
the reserpine band from solution (B) and the ajmalicine band from solution (C), respectively.
Other four quenching bands are also observed. Subsequently examine the plate under
ultraviolet light (366 nm) through the cut-off filter; the bands corresponding to reserpine
and ajmalicine show blue fluorescence. Other four blue fluorescent bands are also observed.
Spray the plate with modified Dragendorff TS. The bands due to reserpine and ajmalicine are
reddish brown. One white and three reddish brown bands are also observed (Fig. 3).
Loss on drying Not more than 11.0 per cent w/w after drying at 105° to constant weight
(Appendix 4.15).
Foreign matter Not more than 0.5 per cent w/w (Appendix 7.2).
Acid-insoluble ash Not more than 1.0 per cent w/w (Appendix 7.6).
Total ash Not more than 6.0 per cent w/w (Appendix 7.7).
Ethanol-soluble extractive Not less than 5.0 per cent w/w (Appendix 7.12).
Water-soluble extractive Not less than 14.0 per cent w/w (Appendix 7.12).