Isolation and characterization of irritant components of Euphorbia pilulifera L.

Euphorbia pilulifera is commonly found weed along road sides and loamy soils. This weed is commonly used as treatment of female disorders and respiratory problems. The latex of this weed causes irritation on hand on contact. To evaluate its irritant potentials, the dermatological investigation of irritant principles from locally occurring Euphorbia pilulifera was carried out. For this purpose, after collection and drying, a series of solvents with increasing polarity were used for the successive extraction of non-polar compounds (petroleum ether extract), constituents of intermediate polarities (chloroform extract) and polar constituents (methanol extract) from the whole herb of Euphorbia pilulifera. The chloroform extract of this weed was found most irritant to rabbit ' s skin. Chloroform extract was further subjected to column chromatography; four fractions Ep 1 to Ep 4 were isolated from active chloroform extract by column and thin layer chromatography. The irritant potentials of these isolated fractions were evaluated on rabbit 's skin. Two fractions out of the four, Ep 1 and Ep 3 appeared to be the most irritant than others. A possible structure activity relationship of these active compounds was discussed in order to establish their activity.