Page 129 - Pharmacognosy-I (02-06-06-102)

Sclereids or stone cells :
- They have thick lignified usually stratified walls and narrow to wide

branching lumen.
- They vary in shape from rounded to irregularly branched, sometimes
elongated but the length is never many times as the breadth. (D.F. fibres
which are very much elongated, occurring either singly or in groups.

Scheme for the Description of Barks: Refer to practical

Medicinal & Pharmaceutical Barks

Cascara Bark

Botanical origin : It is the dried stem-bark of Rhamnus purshianus

Family Rhamnaceae, collected at least one year before being employed
medicinally.
It yields not less than 8.0% of hydroxyl anthracene glycosides of which
not less than 60.0% consists of cascarosides.

Macroscopic characters :

The shape is almost in quills or channeled pieces.

-The outer surface is dark brown, reddish-brown,

smooth or longitudinally ridged, shows occasional
transversely elongated lenticels, usually covered with
grey or whitish lichen, epiphytic yellowish-green tufted
moss and foliaceous liver-worts.

-The inner surface is dull yellowish-brown to dark

reddish-brown, longitudinally striated,

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