Page 266 - Pharmacognosy 2 PG303

Pharmacognosy-2 (PG303) Level 2 Clinical Pharmacy-Pharm D

root-scar a slender xylem is distinctly visible. In the untrimmed rhizome the roots
are very numerous and stout. They completely envelop the rhizome, so that the
untrimmed drug is much more bulky than the rhizome alone. The roots are usually
dull grey or yellowish in color and commonly show a disposition to shrivel
longitudinally rather than transversely. The rhizome frequently divides into 2-3
branches. The drug breaks with a short fracture, the interior being whitish, firm,
compact and starchy. The cortex is about 3 mm thick and is limited internally by a
brownish line, the endodermis. The stele occupies the central region, 1-1.5 cm in
diameter.

Scattered vascular bundles are present in both cortex and stele, being most
numerous on the outer part of the stele. Occasional vascular bundles traverse the
cortex from the pericycle to the bases of the adventitious roots. At the center of the
stele the bundles are somewhat elongated, being cut obliquely. Well-developed
lacunae are present in the outer part of the cortex of the roots and the stele has a
central pith surrounded by a ring of alternating bundles of xylem and phloem.

Powdered veratrum is bitter and is characterized by the abundant fragments
of parenchymatous cells, some show idioblasts of bundles of acicular crystals of
calcium oxalates, and the others contain plenty of starch granules.

1. Veratrum Rhizome; sliced rhizomes.
2. Longitudinal cut; a, cortex; b, endodermis; c, root trace; d, ground tissue; e,
vascular bundles.
3. Transverse cut a, root-trace; b, cortex; c, endodermis; d, vascular bundles; e,
ground tissue.

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