Vitex negundo is a medicinal plant renowned for its wide spectrum of therapeutic properties, including significant anticancer activity. This study explores the inhibitory effects of V. negundo methanolic extract and essential oil on α-amylase purified from the serum of Iraqi lung cancer patients, as well as their cytotoxic effects on the A549 human lung cancer cell line. α-Amylase, an enzyme involved in carbohydrate metabolism, exhibits altered activity under cancerous conditions, making it a potential therapeutic target. The enzyme was purified through a multi-step procedure comprising ammonium sulfate precipitation, dialysis, ion-exchange chromatography, and gel filtration chromatography. This process resulted in an increase in specific activity from 0.94 to 17.0 U/mg protein. Both extracts of V. negundo were assessed for their capacity to inhibit α-amylase activity and reduce the viability of lung cancer cells. The methanolic extract demonstrated a more pronounced inhibitory effect on α-amylase (88.4% at 10 µg/mL) compared to the essential oil (77.0% at 10 µg/mL). Moreover, MTT assay results indicated concentration -dependent cytotoxicity against A549 cells, with IC₅₀ values of 68.79 µg/mL for the methanolic extract and 81.14 µg/mL for the essential oil. These findings underscore the potential of V. negundo—particularly its methanolic extract—as a promising natural anticancer agent, capable of targeting cancer-related metabolic pathways and suppressing tumor cell viability. The results warrant further investigation into the development of V. negundo-based therapeutics for lung cancer treatment.


