Counter irritant activity of carthamus oxycantha

Many locally occurring species of Asteraceae are used as medicinal plants by various tribal and ethnic communities in Pakistan. Carthamus oxycantha is often occurs as weed in cultivated fields. Folk medicines indicated its use as an anti inflammatory and wound healing plant. It is used for wound healing by the local population in the form of powder paste. No scientific report, about the behavior of this plant has so far been published. The counter irritant studies of locally occurring Carthamus oxycantha was carried out. The main objectives of the project were to evaluate its wound healing effects on animal skin and the identity and characterization of chromatographically isolated fractions. For this purpose, different solvents with a broad range of polarity were successively used to extract non-polar compounds [petroleum ether extract], constituents intermediate polarities [chloroform extract] and polar constituents [methanol extract] from the whole herb of Carthamus oxycantha. The counter irritant activity of the crude extracts and isolated fractions was evaluated on rabbit's skin. Five fractions Co-1 to Co-5 were isolated from the active chloroform extract by column and thin layer chromatography. Co-1, Co-3 and Co-5 appeared to be the most potent counter irritant than others. A possible structure-activity relationship of these active compounds was investigated by using spectroscopy [UV and FTIR analysis]

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

Identification and evaluation of counter-irritant potential of crude extract of Malva parviflora L. by WHO recommended methods

Plenty of medicinal plants are available in Pakistan and are in human use as herbal medicines from ancient time. Present work is based on the evaluation of the use of Malva parviflora in skin irritation problems. For this purpose, powdered plant material [The aerial part and roots separately] was extracted by using successive solvent extraction method using petroleum ether, chloroform and methanol. Resulting three crude fractions were subjected to counterirritant investigations on rabbit's ear. Petroleum ether fraction exhibited prominent counter- irritant potential. Five compounds named, as MP-1, MP-2, MP-3, MP-4 and MP-5 were isolated from petroleum ether extract by column and thin layer chromatography. These compounds were subjected to UV spectrophotometer for detection of absorption of light, then FTIR for specific functional group identification and counter-irritant potentials was evaluated on rabbit's ear skin. The MP-1 and MP-2 exhibited excellent counter-irritant activity in different dilutions than others. However, dilution 100microg/ml showed maximum activity