Page 72 - Pharmacognosy 02-06203

It contains mainly alkaloids: the major one is called coniine which is a steam volatile
alkaloid (about 1-2.5 %) together with other related alkaloids as: N-methyl coniine,
conhydrine, γ -coniceine, etc…

(N.B.) When hemlock is treated with solution of potassium hydroxide it develops a strong
bad mouse-like odour owing to the liberation of the alkaloid coniine.

Uses:

Hemlock was used in old medicine in asthma, whooping cough,tetanus and epilepsy. But
it is not now used. Coniine depresses the motor nerve endings resulting in respiratory
paralysis followed by death.

Capsicum (Cayenne pepper)

It is the dried ripe fruits of Capsicum frutescens L., usually devoid of the calyx.

Synonyms: Chilies.

Macroscopic characteristics:

Shape: ovoid-conical fruits. Size: 15-25 mm long and 5-8 mm wide, apex: obtuse, abruptly
tapering at the base where the calyx and pedicel may be attached. Pericarp: orange-red,
translucent, glabrous, leathery and somewhat shriveled.

The fruit is divided into two loculi by a membranous, longitudinal dissepiment, each
loculus containing five to ten seeds, loose or attached to the dissepiment.

Seeds: flattened, sub-reniform, about 3-4 mm long, 2.5-3 mm wide and 0.5-1 mm thick,
with a smooth, hard, yellowish-brown testa.

Calyx: greenish-brown,hard,about 4 mm long,cup-shaped with five inconspicuous teeth.

Pedicel: slender, smooth, about 1-2 cm long.

Organoleptic properties:
Odour slight, characteristic; taste extremely fiery and pungent, strongly sternutatory and
irritant to skin and mucous membranes Microscopic characteristics:

Epicarp: a single layer of sub-rectangular cells, often arranged in rows of five to seven,
with thickened outer walls and a striated cuticle. Mesocarp: thin -walled, consisting of five
to ten layers of parenchyma containing yellowish-red oily droplets, with occasional cells
containing microsphenoidal crystals of calcium oxalate and an innermost layer of giant
cells filled with oil globules.

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