The genus Achillea is one of the most important genus of the Asteraceae family and many species of Achillea are used in traditional medicine to treat several ailments.

The aim of the current research was to evaluate in vitro cytotoxic activities of n-hexan, chloroform, ethyl acetate and methanol extracts and to isolate the active compounds from the extract showing the strongest cytotoxic activity. In addition to this, it was aimed to evaluate the biological activities (cytotoxic, antioxidant, anti-urease, anticholinesterase, antimicrobial) of different extracts and active compounds from Achillea monocephala.

The in vitro antioxidant, cytotoxic, anti-urease, anticholinesterase and antimicrobial activities of different extracts from A. monocephala aerial parts were examined. The structures of the active compounds were determined by NMR techniques, UV, IR and LC-MS/MS analysis and their biological potential was examined.

The chloroform extract showed strong and selective cytotoxic activity on the cancer cell lines (MDA-MB-231, MCF-7). Besides, this extract exhibited stronger antimicrobial activity than other extracts. Therefore, through activity-guided procedures, luteolin, naringenin and 8-hydroxy-salvigenin compounds were isolated from this extract. The methanol extract showed stronger antioxidant (DPPH, ABTS, CUPRAC) and anticholinesterase activity than other extracts. The n-hexan extract exhibited the highest anti-urease activity. In this study, it was determined that the isolated compounds had a strong biological activity. Naringenin compound had stronger ABTS radical cation scavenging and ferric reducing/antioxidant power, cytotoxic and antimicrobial activity than other compounds. 8-hydroxy-salvigenin compound showed the highest urease and acetylcholinestease enzyme inhibition.

The results of this study suggest that the extracts and isolated compounds from the A. monocephala may be used as antioxidant, cytotoxic, anti-urease, anticholinesterase and antimicrobial agents in the future.