2.5.2.2 Psoralen
Synonyms Lata-kasturi (Bengali); Bahuchi (Sanskrit).
Biological Sources They are the dried ripe fruits of Psoralea corylifolia Linn., belonging to the family Leguminosae. Psoralen is also found naturally in more than two dozen plant sources, namely: Bergernot, Limes, Cloves: family Rutaceae; Figs.: family Moraceae.
Geographical Sources It is grown almost throughout India as a weed in abandoned locations. It is also found in Ceylon. Several species of Psoralea have been used medicinally in America.
Description
Colour : Dark chocholate to black
Odour : Pungent and characteristic after crushing the fruits
Taste : Unpleasant, bitter and acrid
Size : 3 to 5 × 2 to 3 mm
Shape : Pods are ovoid, oblong beam shaped
Chemical Constituents The fruits of P. corylifolia invariably contain fluorocoumarin compounds known as psoralen and isopsoralen as shown below:
The seed kernel of P. corylifolia is found to conatin psolaridin as given below:
The plant also contains substituent components of the linear molecule, such as:
8-methoxypsoralen and 5-methoxypsoralen (or bergapten); besides angular molecules, such as: anglicin and isobergapten.*
* It has been observed that the naturally occurring psolarens lower the phototoxic potential whereas the anglicins may enhance it.
However, in the recent past two more compounds, namely: psoralenol and bavachromanol have been reported.
Besides the fruit contains a variety of other chemical constituents, for instance: fixed oil (10%); resin (8.9%); essential oil (0.05%) and small amounts of raffinose and a pigment.
Chemical Tests (For Psoralen)
1. To a small amount of drug add a minimum quantity of alcohol for complete dissolution. Add to this 3 volumes of propylene glycol, 5 volumes of acetic acid and 43 volumes of water and shake well. The appearance of a blue fluorescence under UV-light indicates its presence.
2. The drug is dissolved in minimum amount of alcohol and on addition of a little sodium hydroxide solution exhibits a yellow fluorescence in UV-light.
Uses
1. The seeds are recommended in leprosy, leucoderma and other skin manifestations. They are also used for snake bite and scorpion sting.
2. The oleroesin extracts of seeds are employed to cure leucoderma patches.
3. The seeds also find their use as stomachic, anthelmintic, diuretic and diaphoretic.
4. It is used orally as a laxative.
