Page 158 - Pharmacognosy-I (02-06-06-102)

Wild cherry Bark

Botanical origin : It is the dried bark of Prunus serotina family

Rosaceae. It is collected in the autumn at which time it is most active.
After careful drying it should be kept in air tight containers.
It occurs in curved or channeled pieces. The dry bark is almost
odourless, but after moistening it develops it an odour of benzaldehyde.
The taste is astringent, aromatic and bitter, resembling that of bitter
almonds.

Constituents :

- Cyanogenetic glycoside prunasin and the enzyme prunase.
- On hydrolysis yield glucose, benzaldehyde and hydrocyanic acid.

- Resin which yields the fluorescent compound scopoletin on hydrolysis.
- Benzoic acid, trimethylgallic acid, p-coumaric acid and some
tannin.

Test for hydrocyanic acid : (Guignard's paper test).

- In a test tube place a freshly crushed wild cherry bark and 5 ml of
water, then insert a strip of moist sodium picrate paper in the neck of
the test tube by a well fitted cork.
- Imerse the test tube in water bath for few minutes.
-The colour of the sodium picrate paper will change to brick red (sodium
isopurpurate).

Uses :

Wild cherry is mainly used in cough preparations to which it
gives mild sedative properties and a pleasant taste. It also has

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