Counter irritant activity of Carthamus oxycantha

Abstract

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).