This study aimed to explore and separate the phytochemicals of the whole plant Conyza canadensis, a naturally growing plant in Iraq, since no phytochemical research was done previously in Iraq. The whole plant of C. canadensis was defatted by maceration in hexane for 24 hours. The defatted plant materials were extracted using Soxhlet apparatus, the aqueous ethanol 85% as a solvent extraction for 9 hours, and fractionated by petroleum ether, chloroform, ethyl acetate, and n-butanol. The petroleum ether, chloroform, and ethyl acetate fractions were analyzed by high-performance liquid chromatography (HPLC) for their steroids, alkaloids, and polyphenolic (phenolic acids and flavonoids) contents. One alkaloid was isolated from chloroform fraction by HPLC, and three polyphenolics compounds were isolated from ethyl acetate fraction by preparative thin-layer chromatography (TLC), then identified by HPLC and high-performance thin-layer chromatography (HPTLC). The different chromatographic and spectroscopic results revealed stigmasterol, β-sitosterol in petroleum ether fraction, harmine alkaloid in chloroform fraction, quercetin, quercitrin, apigenin, p-coumaric acid, and caffeic acid in ethyl acetate fraction of C. canadensis. Three polyphenolics compounds (p-coumaric acid, caffeic acid, apigenin), and harmine alkaloid were isolated from the whole plant and matched their retention time with the related standards by HPLC and by measuring their max Rf values by HPTLC analysis.
