Page 355 - Pharmacognosy 2 PG303 (1)

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

Dried Extracts

▪ This group includes drugs which are prepared by evaporating the aqueous decoction of parts of certain plants
or animals e.g., Agar- Agar and gelatin.

Agar-Agar Gelatin

Origin Is the dried mucilaginous Is the protein obtained by boiling the collagenous
substance prepared from tissues of animals (skin, tendons, bones) with water,
red algae. evaporating the aqueous extract and drying the
residue in air.

Shape

Sheets or powder

Translucent strips Or granulated powder
Color Greyish white with yellowish tint. Pale yellowish

Texture Tough (hard to break) Brittle
Odor Marine algae odor Slight

Taste Salty mucilaginous taste Slight
Solubility Insoluble in cold water Insoluble in cold water
Soluble in boiling water → stiff jelly soluble in hot water →translucent jelly on
on cooling cooling

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