Wild Cherry Bark

2.6.2 Wild Cherry Bark

Synonyms Viginian Prune Bark; Wild Black Cherry Cortex; Pruni.

Biological Source It is the dried bark of Prunus serotina , Ehrk, and Prunus macrophylla Sieb et Zucc, belonging to family Rosaceae.

Geographical Source Wild Cherry bark is found to be indigenous to the Eastern States of USA and certain parts of Canada. However, in the United States it is found abudantly in Dakota, Florida,

Missisipi, North Carolina and Virginia.

Preparation It has been established that the wild cherry bark possesses the highest potency only during the autumn. Therefore, the bark is mostly collected during this period. As the inner layer of

the bark contains a substantial amount of HCN, hence soonafter collection it is necessary to get rid of the inner layer of cork. Consequently, after the removal of cork as well as a portion of the cortex, the exposed surface of the bark exhibiting phloem more or less give rise to an uniform dark brown coloured product, which is commercially known as Rossed Bark. The resulting rossed bark is dried

in the shade and stored carefully in a dry place for onward trasmission to several countries as a valued export material.

Description

Colour : Dark-brown colour

Odour : Mostly very faint; but when slightly moisten it has an odour resembling to

that of benzaldehyde (bitter almond like)

Taste : Bitter and astringent

Size : Length = 10 cm; Width = 4 cm; Thickness = 3-4 mm

Shap : Mostly curved or chanelled

Fracture : Short and granular

Inner Surface : Reddish brown and longitudinally striated

Outer Surface : ‘Rossed Bark’ - Rough with pale buff coloured lenticel scars; ‘Unrossed

Bark’—Reddish brown to brownish black, smooth, glassy and exfoliating cork having prominent whitish lenticels.

Chemical Constituents Wild cherry bark essentially contains a cyanogenetic glycoside termed as prunasin (or mandelonitrile glucoside) as shown below:

Prunasin

cyanic Acid

d-Prunasin undergoes hydrolysis in the presence of the enzyme prunase, usually present in the bark itself, to yield one mole each of bnzaldehyde, glucose and hydrocyanic acid.

Besides, the drug also contains p-coumaric acid, scopoletin i.e., b-methylesculetin, benzoic acid and trimethyl gallic acid.

Chemical Tests The chemical tests are same as described under Section 2.6.1.

Uses

1. The syrup of wild cherry is mostly employed as a flavoured vehicle in cough syrup.

2. It is also used as a sedative expectorant.

Source: Pharmacognosy And Pharmacobiotechnology By Ashutosh Kar